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Friday 22 July 2011

NASA's Inspiring, Enlightening, and Successful Search for New Earths

Journey that began four decades before Columbus sailed for the New World finally ended when the Kepler space telescope snared a few errant photons as they shot past Earth’s orbit en route to infinity. The light had sped through space for 560 years, traveling more than three quadrillion miles from a star much like our sun. Captured by Kepler’s digital sensors, transformed into bytes of data, and downloaded to computers at NASA’s Ames Research Center near San Francisco, the processed starlight slowly revealed a remarkable story: A planet not much bigger than Earth was whipping around its native star at a blistering pace, completing an orbit—its version of a “year”—in just over 20 hours.
Aside from its size, the planet bears little resemblance to Earth. It circles so close to its star that its surface temperature probably exceeds 2,500 degrees Fahrenheit, hot enough to melt iron. Nevertheless, the planet’s detection was a technical and intellectual coup, a rite of passage for Kepler. The planet, dubbed Kepler-10 b when NASA announced its existence this past January, was the smallest world yet found beyond our solar system. Its discovery proved that the Kepler spacecraft, which was launched in March 2009, could indeed do what its designers had boldly promised: find small, Earth-size planets around distant stars, a task that once seemed so difficult as to border on the absurd.
Kepler-10 b was merely a preview. A month after the January announcement, NASA released its first full data set from the Kepler mission, and the results left astronomers straining for superlatives. “Frankly, we’re overwhelmed,” says Geoff Marcy, an astronomer at the University of California, Berkeley, and a member of the Kepler team. “What NASA is doing is akin to the transoceanic voyages of the 15th century—the voyages that opened up the whole world. With the Kepler telescope, we’re learning about the properties of planets across the cosmic ocean. This is history. It’s Armstrong stepping off the bottom rung.”
Kepler monitors 156,000 stars, less than 0.0001 percent of the galaxy’s population. Like some cosmic wildcat drilling operation, Kepler has struck a gusher, discovering 1,235 possible new worlds in its first four months of operation. That number doubles the previous total of just over 500, painstakingly gathered over the last 16 years. Prior to 1995, keeping track of all the known planets around other stars like the sun was easy—the tally stood at an even zero.
The bulk of Kepler’s data have not yet been studied, and the mission will keep going for at least two and a half more years. But it is already shredding the textbooks, showing that our galaxy (at least the fraction of it seen by the spacecraft) contains a far more exotic assortment of planets than astronomers expected to find. “We’re learning about a diversity of worlds in our universe that we had no clue about beforehand,” Marcy says. “Rocky planets, yeah, we thought there might be some of those. By the way, we’re finding some rocky planets that are even denser than Earth. But we’re also finding these mini-Neptunes, a class of planet for which we have no examples in our solar system. They’re like small Neptunes but with huge amounts of liquid water around a rocky core.”
Also on the list are 67 planets roughly the size of Earth, give or take a thousand miles or so in radius; 288 “super-Earths” up to twice Earth’s diameter; 662 Neptune-size planets; and 184 giants rivaling or exceeding Jupiter in size. The simple statistics from Kepler say that Earth-size planets are widespread.
Just two years into its mission, Kepler is well on its way toward determining whether planets like Earth are rare or common. But that is just the first domino as scientists try to topple the much bigger questions, the kinds that make the hairs stand up on the back of your neck. Does life exist on other planets? Are planets with life common? Are any other intelligent beings out there?
For the first time, we have a handle on the odds, and the numbers beaming in from Kepler are not only encouraging but staggering. “Our galaxy contains 200 billion stars,” Marcy says. “I would guess that at least 30 percent of them have an Earth-size planet. So 30 percent of 200 billion, that’s at least 60 billion Earth-size planets just in our galaxy alone”...


Science Video

Tuesday 19 July 2011

An Easy Guide To Blogs

Almost everyone doing some sort of business online seems to have a blog these days, they have become very popular and with good reason: a lot of money can be made with a couple of blogs. If they’re not blogging for fun they are certainly blogging for cash. It has become so popular that a lot of people now use only blogs instead of the traditional website to get things done. Blogs can be used to promote businesses get information about anything or you can even give your opinion about anything. The good thing about blogs is that they are constantly updated with fresh information and ideas, that is, if the blog is maintained correctly by the owner – This is what makes them so popular with the search engines. Blogs usually get high ranking on the search engines because of the constant update of information. Search Engines love fresh content and if it’s on your blog first then your blog will be the first to get listed and ranked.

A Few Advantages of having a Blog

1. Blogging can be an excellent form of advertising for your products or business

2. Blogs are so easy to set up and they are free.

3. They usually get very high rankings in the search engines.

4. They usually contain constant updates with relevant information.

5. Blogs can be an excellent cash generator.

Anyone doing business online should by now have a blog or two or three, and if not they should start blogging as soon as they can. It is an excellent way to get your business out there and be noticed. Good Increases in sales usually follow a good blog promotion. There are a lot of ways to make a lot of money using only blogs. You can sell products related to your blog, or even unrelated. People have lots of different interests. You can advertise for someone else by placing their banners or text ad on your blog. You can also use Adsense ads to generate extra income.
Creating and starting a blog is very easy, it can be a lot of fun and exciting, especially when you start making some money from your efforts.

For a blog to be effective you must remember to update your blog quite often; every day is good or every other day. It definitely needs to be updated at least once a week. It’s important to update it. Your blog has to be filled with useful and interesting information that makes sense to people and they can use or learn from the information on your blog. Write about your area of expertise, topic or business area.

Blogs are great, but like everything else, in order to be any good at it, you will need to learn about it. Especially if you are a complete newbie at blogging, but don’t worry, it is so fast and easy to learn. If you want to know all you need to know about blogging then I would recommend you take a look the Bloggers Guide below.

A Checklist for Used Computers

It is very important to check a used computer thoroughly before buying it as it may lead to problems in the future. A hard drive will not show any outward signs but may be deteriorating. The same way the needle can suddenly slip and can cause scratches on the disc ultimately leading to memory loss as used computers can fail any time. If they are checked, the faults which may occur can be known. Let us first see the possible faults which may occur while purchasing a used computer.

Hard disk failures can happen due to heavy wear and tear over a period of time. The read and write heads of a hard disk are used to retrieve or recode data stored on the hard disk with the help of a disk platter rotating at a high speed. Over a period of time the risk of failure or malfunction of disk increases. Faulty sectors of the hard disks can be found out only if a full surface scan is done on the used computer. The scanning time depends on the capacity and size of the hard disk of the used computer. Many skip this procedure due to the time consuming process of scanning the whole disk and end up purchasing a used computer with a faulty sector.

Monitors need to be checked for any faults. The malfunctioning of a monitor is called a “dry joint” which results in the monitor not working after getting warmed. This can be checked only if the monitor is made to work for at least 20 to 30 minutes after switching on the computer.

Next is to look for any possibilities of the central processing unit getting freezed. Normally all the central processing units have a fan and heat sink for keeping the unit cool. Over a period of time the fans may not work properly due to the accumulation of dust and dirt resulting in over heating of the central processing unit and even leading to stopping from functioning. While buying a used computer the fan needs to be checked and if any abnormal sound is heard, it is not good for purchase.

The used computer may have a higher possibility of getting crashed and freezed due to the usage of the operating system for a good number of years. There may be a cache or RAM fault due to the over exposure leading to loss of data. To increase the performance of the computer and to avoid crashing, the operating system of the used computer can be reinstalled with a new operating system or a fresh one.

While checking the used computers for any faults, it is good to disconnect the network connection if any present before performing the tests. Also it is advisable to check the drives like the CD or DVD by opening and closing them and also playing something on the drives to see how they work. Monitors of the used computers can be checked for the resolution and brightness by trying different options of color, settings and so on. To check the hard disk size the CMOS setup can be gone through and to verify the speed of the processor, cache and RAM the pause button is pressed when it appears on the screen during the booting process. To check the booting process, the computer can be turned on and off a few times and seen how it responds. Checking should be done to see if all the passwords are erased before purchasing a used computer.

Friday 15 July 2011

Considering a Prepaid Cell Phone Plan

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With a prepaid phone plan, you are automatically approved. There is no credit check required – you simply choose your phone and your plan and you are done. In the past, you were limited in choice of phone styles and features, but this is fast becoming a thing of the past. So if you have less than perfect credit, a prepaid cell phone plan may be right for you.

With a prepaid phone plan, you do not have to worry about a bill each month, as you would with a typical cell phone plan. This is because you pay for your minute usage in advance. When you use all your minutes, you can simply buy additional minutes.

Prepaid cell phone plans also include features that you would find with typical contract cell phone plans. They have really come a long way. You can choose voicemail, caller ID, and even text messaging. You even have access to the latest cell phone models, such as camera phones and music capable phones.

Prepaid cell phone plans are also a great option for teenagers who are just learning to handle responsibility. You have peace of mind as a parent knowing that you can stay in touch with your child at all times. You are also freed from worry knowing that your child cannot create any surprise bills for you at the end of the month.

You may also consider a prepaid cell phone plan if you rarely use your cell phone or allocate its use for emergency purposes only.

A prepaid phone plan is great for those with less than the best credit or for those who have little money to spend. It is a great tool for learning financial management skills and responsibility, if you struggle in these areas.

One of the defining factors for many of those who are considering a prepaid cell phone plan is freedom. You are free from contracts. You are free from a monthly bill. You are free to change and switch companies and cell phone plans as often as you wish with a prepaid cell phone plan.

Shopping for a prepaid phone plan is no different than shopping for a typical cell phone plan with a contract. Shop around, assess your needs and choices, and then choose the best prepaid plan for your lifestyle.

Bluetooth And Infared

With new electrical devices being produced every day, the problem of connecting things is becoming more and more complex in nature. The system that comprises computers and other electronics makes use of varieties of wires, cables, etc.

These parts will communicate through light beams, lasers, radio signals, and infrared. The problem however, is the devices and technology is often the connection between each component. Therefore, most electronic systems aren't used to their full extent due to the problems and imperfections.

To help simplify things, a solution was created -the solution of Bluetooth. Bluetooth is wireless and automatic, offering users a variety of features that have simplified the art of connection. Bluetooth has revolutionized the standard methods of connecting things to enabling almost anything to be connected to a single system.

Aside from Bluetooth, there are other ways of connecting wireless devices. One example of such is the IR or infrared. Infrared allows low frequency light waves to transmit signals to another component. This technology is easy to create and the cost of putting the IR device into a system is rather low.

Infrared technology is a one to one process. Due to the limitation, you may only send signals from one device to another, similar to a television set and remote control. You can only transmit signals between the two although not with a seperate system.

Aside from the fact that these two natures of infrared are obstacles to acquiring results, these same qualities have worked in advantage to the connection. Infrared devices need to be lined up directly, meaning too little interference can occur between the transmitters and receivers.

The technology behind Bluetooth works by transmitting signals through low frequency radio signals. The path of communication is working on 2.45 GHz, which is the same frequency band used in ISM devices.

Advantages And Disadvantages Of Bluetooth

Bluetooth has a lot to offer with an increasingly difficult market place. Bluetooth helps to bring with it the promise of freedom from the cables and simplicity in networking that has yet to be matched by LAN (Local Area Network).

In the key marketplace, of wireless and handheld devices, the closest competitor to Bluetooth is infrared. Infrared holds many key features, although the line of sight it provides doesn't go through walls or through obstacles like that of the Bluetooth technology.

Unlike infrared, Bluetooth isn't a line of sight and it provides ranges of up to 100 meters. Bluetooth is also low power and low processing with an overhead protocol. What this means, is that it's ideal for integration into small battery powered devices. To put it short, the applications with Bluetooth are virtually endless.

Disadvantages

Bluetooth has several positive features and one would be extremely hard pressed to find downsides when given the current competition. The only real downsides are the data rate and security. Infrared can have data rates of up to 4 MBps, which provides very fast rates for data transfer, while Bluetooth only offers 1 MBps.

For this very reason, infrared has yet to be dispensed with completely and is considered by many to be the complimentary technology to that of Bluetooth. Infrared has inherent security due to its line of sight.

The greater range and radio frequency (RF) of Bluetooth make it much more open to interception and attack. For this reason, security is a very key aspect to the Bluetooth specification.

Although there are very few disadvantages, Bluetooth still remains the best for short range wireless technology. Those who have tried it love it, and they know for a fact that Bluetooth will be around for years to come.

10 Benefits Of Bluetooth

Below, are 10 benefits and reasons to use Bluetooth technology.

1. Wireless - As you probably already know, there are many benefits and advantages to using wireless devices. Along with improving safety as a result of eliminating wires you don't need, wireless also offers you plenty of other advantages. When traveling with your laptop or other wireless devices, you'll no longer have to worry about bringing connection cables.

2. Bluetooth is actually inexpensive - The technology of Bluetooth is cheap for companies to implement, which results in lower costs for the company. These savings are then passed from the company on to you.

3. Bluetooth is automatic - Bluetooth doesn't have you set up a connection or push any buttons. When two or more devices enter a range of up to 30 feet of each other, they will automatically begin to communicate without you having to do anything.

4. Standardized protocol - Bluetooth is standardized wireless, meaning that a high level of compatibility among devices is guaranteed. Bluetooth will connect devices to each other, even if they aren't the same model.

5. Low interference - Bluetooth devices almost always avoid interference from other wireless devices. Bluetooth uses a technique known as frequency hopping, and also low power wireless signals.

6. Low energy consumption - As a result of Bluetooth using low power signals, the technology requires very little energy and will use less battery or electrical power as a result. This is an excellent benefit for mobile devices, as Bluetooth won't drain the battery.

7. Sharing voice and data - The standard for Bluetooth will allow compatible devices to share data and voice communications. This is great for mobile phones and headsets, as Bluetooth simplifies driving and talking on your cell phone.

8. Instant PAN (Personal Area Network) - You can connect up to seven Bluetooth devices to each other within a range of up to 30 feet, forming a piconet or PAN. For a single room, you can also set up multiple piconets.

9. Upgradeable - Upgradeable is the standard for Bluetooth. There are newer versions of Bluetooth in the works, which offer many new advantages and backward compatible with older versions.

10. The technology stays - Bluetooth technology is a world wide, universal wireless standard. With it being as popular as it is, you can count on it being around for years to come. As more and more devices start to use Bluetooth technology, more manufacturers will be eager to make their products compatible. A chain reaction will occur, making Bluetooth the standard for cutting edge wireless.

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Thursday 14 July 2011

Distant light hints at size of space-time grains

THE light from a spectacular gamma-ray burst has been used to set the most stringent constraints yet on the size of the "grains" of space-time. The conclusion has been praised for pushing boundaries in the search for a theory of everything but has also drawn criticism for exaggeration.

A big challenge in physics is how to combine Einstein's general relativity, which describes gravity, with quantum mechanics to create a theory of quantum gravity. The best efforts on this front include string theory, which argues that everything in nature arises out of the vibration of tiny strings in 10-dimensional space-time, and loop quantum gravity (LQG), which shows mathematically that the fabric of space-time is woven out of gravitational field lines. Both approaches lack experimental support, however.

So cosmologists have been looking for signs of quantum gravity in the distant universe. One prediction of both string theory and LQG is that space-time is not smooth but "grainy" at extremely small scales. In theory, this graininess can be observed by studying particles from the same source but with different energies, to see if they are affected differently by the structure of space-time.

Over the past few years, terrestrial telescopes such as the Major Atmospheric Gamma-ray Imaging Cherenkov Telescope (MAGIC) in the Canary Islands and the High Energy Stereoscopic System (HESS) in Namibia have seen low-energy photons from a gamma-ray burst (GRB) arriving before their high-energy counterparts. While this could be due to delays in emission at the source, it could also be caused by the interaction of photons with the structure of space-time (New Scientist, 15 August 2009, p 26).

Now a team has used data from the Integral satellite, run by the European Space Agency (ESA), to study an entirely different effect: the polarisation of light of different energies from a GRB. In December 2004, Integral observed one of the brightest GRBs ever recorded. "We were lucky because the GRB was in the field of view of the instrument," says Philippe Laurent of CEA, the French government's atomic energy research institute in Saclay.

Earlier this year, astronomers used the Canada-France-Hawaii Telescope on Mauna Kea, Hawaii, to estimate the distance to the galaxy that produced this GRB, putting it some 275 million light years away.

Now Laurent and his colleagues have used the combined data to look for effects of quantum gravity. One idea is that if space-time is composed of indivisible grains, then this would polarise photons in a way that depends on their energy. This effect would accumulate over cosmological distances and so be observable from Earth. Yet the team found no such effect (Physical Review D, DOI: 10.1103/physrevd.83.121301).

Considering the extremely high quality of Integral's data, this puts an important limit on the size of the grains of space-time. According to an ESA press release, it means they must be smaller than 10-48 metres, many orders of magnitude smaller than the Planck length of 10-35 metres, the universe's smallest length scale.

However, this conclusion is drawing criticism. Carlo Rovelli, who studies LQG at the Centre for Theoretical Physics in Marseille, France, points out that grains of space-time cannot be smaller than the Planck length and says that the limit is "wrong".

The strange conclusion is a consequence of the way in which the data was analysed with respect to a very specific model of quantum gravity, which has fallen out of favour with some theorists. The main versions of both string theory and LQG don't support such a model. "This result does not contradict the main expectations [of these theories]," says Rovelli. Laurent agrees that the work has limitations. He admits that it doesn't affect theories that make more subtle predictions. These are still beyond the reach of today's experiments.

Nonetheless, the work demonstrates astonishing progress. Giovanni Amelino-Camelia, who studies quantum gravity at Sapienza University of Rome, Italy, is thrilled with the quality of observations and the analyses carried out by Laurent's group. He says this kind of work was unthinkable just a decade ago and raises hopes that more subtle effects could soon be tested.

This would rely on astronomers finding ever more distant GRBs and studying photons that are widely separated in energy. "The pace of improvement is well beyond the most optimistic expectations a decade ago," Amelino-Camelia says. Even Rovelli agrees that the future looks promising. "I share this excitement," he says.

Wednesday 13 July 2011

How Can You Get Maximum From Your Portable Generator

Your portable generator is your only refuge in the case of a power-cut, when there is a great need to keep thing moving and working. To be used as a temporary source of power for emergency after calamity – like, hurricane or tornado - portable generator is a popular option. In such cases, if there is a need for rescue and retrieval, especially during the night, the portable generator can keep machines and lights going for the purpose.

A matter of concern when it comes to a portable generator is that it can be a health hazard to people, if not used properly, more details are located at Honda generator store website. Hence, it is the responsibility of the users to use portable generators in the right way.

Chiefly, there are four main hazards that portable generators can impose:

i) Release of carbon monoxide from the generator’s exhaust

ii) Fires due to improper refueling

iii) Electrocution or shocks due to wrong connections

iv) Loud noise and vibration.

Carbon monoxide is a toxic gas. Its undetectable nature makes it all the more dangerous, as it can lead to death due to suffocation. It is unlike other gases – being colorless and odorless – that it why it is impossible to sense.

Keep your portable generator in places where there is proper ventilation, so as to avoid poisoning due to carbon monoxide. Closed spaces - like a room, basement, or garage – are a complete ‘rule out’, when it comes to placement of portable generator also check out all safety precautions at hondageneratorstore. So are places like windows, doors, or any kind of openings in the house.

If you run the generator indoors, keep in mind that open windows or doors are no guarantee or safety against carbon monoxide build up. In fact, the harmful effects of carbon monoxide can also enter open doors or windows, even if the generator is run outdoors. If anyone experiences symptoms like giddiness, nausea, headache and fatigue, take the person to an open area where he can get fresh air.

Generators, like car engines, get hot when their engines run for a long time, get more details at hondageneratorstore But unlike car engines, generators remain hot for a long period of time, making it impossible for you to refuel them, while running or immediately after they are shut down. The generator needs to be cooled down for a while. Once the temperature is safely low, refueling can be done. Fire can also occur, even before your intention to start refueling it, particularly if your gasoline containers are placed near or beside the generator.

Generators should be considered as ordinary power sources. Since generators do not have safety devices - like circuit breakers and transformers - they can cause harm, more so in case you happen to get electrocuted. Keep every connection clear and clean, to ensure the safety of everyone around. Avoid unnecessary and unsafe connections, as well as tangling ones.

Keep the generator dry, as under no condition should you let it work in the rain. In case it starts raining, use a canopy to cover the generator. Don’t ever attempt to connect any devices when you are barefooted. And under no circumstances should you connect wet electric devices to the generator.

How to Make a Bootable Antivirus Cd

How to Make a Bootable Antivirus Disc

Purpose of this document.
This document will teach you how to make a bootable anti-malware ( bootable antivirus ) cd/dvd step-by-step.

Why Bootable Antivirus?
In a bootable environment we are running a stripped down version of windows in a ram disk (programs are loaded directly into ram), thus the hard drive on the PC is treated as attached storage (like a flash drive). In this state malware (malware consists of viruses, trojans, spyware, adware, rootkits, etc) is helpless and totally at your mercy. This is the best free way to remove any piece of malware with a 100% success rate.

Steps:
Please follow all the steps below:

1. Go to http://ubcd4win.com/downloads.htm
2. Select a mirror with a green status. (like "Mirror#3" for example)
3. When you click on the mirror it will take you to another site where the download will be available.
4. Click the download link for Ultimate Boot CD and save the download to wherever you download stuff.
5. Once the installer has been downloaded double click it.
6. Choose your language
7. Click next about 3 more times and select the file path where you would like to install ultimate boot cd 4 win. Please note that you should have a drive with at least 5-10 gb of free space to allow for future plugin growth. I will choose C:UBCD4Win. The install should take a few minutes.
8. Click Yes to the MD5 Hash Check. The install will continue once the hash check succeeds.
9. Click Yes to see if a patch file exists.
10. Click the checkbox to launch ubcd4winbuilder.exe.
11. Click the "i agree" button.
12. Click "NO" to searching for windows files.
13. Obtain a windows xp operating system disc w/SP2.
14. Explore the disc and copy the entire content (all the folders and files on the windows xp cd) to any location on your computer. You should allocate at least 700 MB of free space for the windows xp disc.
15. Open UBCD4win (if it's not already open). Click Source browse button (3 dots ...) and browse to your i386 folder. My path was C:WindowsXPcd for example.
16. Next go to the media output section and choose a spot for your ISO image to be created. This ISO can be burned with almost any burning software. Once the ISO is burned it will be bootable.
17. Next, click the plugins button. Don't be too overwhelmed here, actually you should be very happy! Look at all those plugins!
18. Now it's time to update our anti-malware software packages.
19. The first one I have on my list is a-squared free anti-spyware. Click that line and then click the config button. A command prompt will automatically open and start downloading the latest updates for that program...totally awesome, isn't it!
20. So, now you need to update all the anti-malware programs in our plugin list. Click each one and then hit the config button.
21. After you're done configing/updating your plugins click the close button.
22. Next, click Build.
23. Click yes to create a directory and then click i agree.
24. At this point your ISO is created and is ready to be burned.

This concludes the How to Make a Bootable Antivirus CD tutorial.

Read more: http://www.articlesbase.com/security-articles/how-to-make-a-bootable-antivirus-cd-380611.html#ixzz1S3YdKH3b
Under Creative Commons License: Attribution No Derivatives

Benefits of having light for bike

Use a bicycle requires different security measures put in place while driving, because cyclists are often most at risk, while on the road. While riding the bike, helmets, and gloves and use a light for bike at night or early morning is advised to increase the safety of the cyclist. It is always advisable to consider the use of the best bikes available LEDs, as very few other light for bike have the same number of advantages. LED lights cycling state of the art technology to provide you and others around you in the light for bike are available in a wide range of sizes, shapes and weights to suit each pilot. They are also capable of supporting a wide range of climatic conditions, ensuring maximum safety on rainy days, foggy days, and foggy days and during morning, afternoon and especially at night.



It is pretty obvious for parents to be scare when their child loved biking so much. It is because they are concern of their safety and so. That is why some companies offered light for bike for the concern of these parents. Of course, they are more of into safety since light for bike can give source of light and visibility for the rider especially if it is really a dark place and the child is crossing a road. A light for bike can be a good source of light to give them the sight of what is heading into then. Parents can actually purchase led as light for bike. These are more of into the best and yet goof source of light for bikes. A light for bike can lessen the fear of the parents and can still choose to have at least played and do your biking as usual.

A light for bike can lead to far off places and will be worth the price you have. So if you know how to get the best light for bike will be a cloud and be with it. A light for bike is in different and have so many types. Therefore, before going to the store you need to know all kinds to choose the best bike for you LED.

There are several types of light for bike available in the market today. Some LED lights bicycles are equipped with high power LEDs only, some have multiple LEDs. LED light for bike varies in size and comes in several attractive colors and nice. There are two best options available for you to shop online and get the best results.

One is "21 LED bicycle front light" that is suitable for bicycle lights, rear flash light, bicycle lamp, and by the end of the torch. This light for bike is very popular among students and parents who use light LED bicycle in his stroller to get good views of the walk on the road a night. Therefore, if you're thinking of buying light for bike, then you should consider buying the bike LED light, as it is of high quality.

Tips On Where To Buy Apple MacBook Pro Laptop Online

Many shoppers are not sure of where to buy an Apple MacBook Pro Laptop online. Just trying to locate online stores selling the Apple Macbook Pro can be a bit overwhelming especially if you're new to the online world. How do you find them? Who can you trust? Is their website easy to navigate? Do they ship promptly at reasonable rates?

Fortunately for you there is at least one online store that will meet or exceed all your online shopping expectations. Amazon.com is the leader in online retail sales by a huge margin. You can be reassured if you buy an Apple i pod touch from this retail giant your shopping experience will be simple and safe.

Your choice for the Mac book Pro is a particularly smart choice for a laptop. The Apple Mac Book Pro 13, the Apple Mac Book Pro 15 and the Apple Mac Book Pro 17 are definitely  more and more popular among consumers. The latest series of Apple Mac book Pro laptops combination of high performance, stunning displays and greater expandability have resulted in many long time PC users converting over to the Macs.

Shopping online at Amazon.com can be both a fun and rewarding experience. Online since 1995 they have pioneered many aspects of shopping online. Their website is fast and easy to use. They have at least 10 shipping fulfillment centers across the United States to ensure quick and reliable delivery of your iPod Touch to your location. Their prices are very competitive and in many cases better than other online retailers. If you time it right you may even cash in on one of their special deals or sales.

Amazon is much more than a book store. They now offer thousands of items in many different categories. You will also be happy to know that free shipping is offered on many items. Some restrictions may apply so please ensure you read the details on each product page. Another great benefit of shopping for your Apple MacBook Pro at Amazon.com is the ability to research the good and the bad simply by reading actual customer reviews in real time. Here are a few excerpts from a few Apple MacBook Pro reviews:

Here's Where To Buy Laptops Online And Save $$$!

Many shoppers are not sure of where to buy laptops online. Just trying to locate online stores selling competitively priced laptops can be a bit overwhelming especially if you're new to the online world. How do you find them? Who can you trust? Is their website easy to navigate? Do they ship promptly at reasonable rates?

Fortunately for you there is at least one online store that will meet or exceed all your online shopping expectations. Amazon.com is the leader in online retail sales by a huge margin. You can be reassured if you buy a Laptop from this retail giant your shopping experience will be simple and safe.

If you're still undecided which laptop is right for you Amazon.com can easily help you with real time easy to do research. First go to the Amazon Bestsellers in Laptops page. Here you can browse the current top 100 bestselling laptops which is updated hourly. If you see a laptop on the list that interest you simply click the link for more details and be sure to read the customer reviews. They can be a goldmine of information.

If you already know which brand of laptop you want, you can simply type the brand name in the search box at the top of laptop bestseller page. To view some sample search result pages simply click the links below:

- If you're looking to buy a Sony laptop online simply enter Sony in the laptop page search box and you should see these Sony Laptop search results.

- If you're looking to buy a Toshiba laptop online simply enter Toshiba in the laptop page search box and you should see these Toshiba Laptop search results.

- If you're looking to buy an Apple laptop online simply enter Apple in the laptop page search box and you should see these Apple Laptop search results.

You should see similar results for any brand name laptop you are trying to find.

Shopping online at Amazon.com can be both a fun and rewarding experience. Online since 1995 they have pioneered many aspects of shopping online. Their website is fast and easy to use. They have at least 10 shipping fulfillment centers across the United States to ensure quick and reliable delivery of your iPod Touch to your location. Their prices are very competitive and in many cases better than other online retailers. If you time it right you may even cash in on one of their special deals or sales.

Amazon is much more than a book store. They now offer thousands of items in many different categories. You will also be happy to know that free shipping is offered on many items. Some restrictions may apply so please ensure you read the details on each product page. Another great benefit of shopping for your laptop at Amazon.com is the ability to research the good and the bad simply by reading actual customer reviews in real time.

So, if you're still trying to decide where to buy a laptop online the smartest decision would be to buy from America's largest online retailer that knows and serves online shoppers like no other.

Can Your Cell Phone Download Music?

Features of music capable phones vary depending on the technology of the phone. Some music capable phones come with built in iTunes software. Others incorporate MP3 players and include expansion slots for more memory. And others will allow you to tune into FM radio from your cellular handset. Many of these music phones will allow you a combination of the aforementioned features.

If your phone has iTunes incorporated, it will hold approximately 100 songs or so. And if you are already a user of iTunes, you can even sync your cell phone to your iTunes software by simply using a USB cable. Then you simply drag and drop your music files from your music library directly to your cell phone.

Music cell phones that include a built in stereo MP3 player will hold approximately 25 songs. In order to increase the ability to store more songs, these phones include a memory expansion slot. The number of songs that you are able to store on your memory card depends on the memory card size.

If you own a newer model smartphone, then you most likely already have an MP3 player incorporated into your cell phone. These smartphones will even allow you to download music from your computer, via such applications as Windows Media Player.

For those of you who love the idea of listening to your favorite radio station via your cell phone, many companies now offer phones that include this capability. You are able to stream live FM radio and satellite radio to your cell phone. Some companies even offer the popular Sirius satellite radio programming through built in media players.

Many mobile carriers allow cell phone users to download software to their cellular handsets that allows access to the carriers’ own music stores. Users can then choose and wirelessly download their favorite music to their cell phones for a small per usage fee.

If you have ever considered purchasing an MP3 player, then purchasing a call phone that can download music may be just the solution for you. You get access to your favorite music and the ability to keep in touch with your friends and family with one device. And since many of the newer cell phone models will fit right into your pocket, convenience and portability are never an issue.

Cell Phone Text Messaging

Cell phone text messaging is exploding worldwide. If you have been struggling to keep your cell phone bill under control, rather than change your plan again, you may consider using the text messaging feature available on almost all mobile phones. You will join the ranks of billions of cell phone text messaging users around the world and maybe even have a little fun in the process.

Usage of the text messaging feature has seen explosive growth. Statistics show that by June of 2004, an average of 100 text messages per person had been sent globally. Text messaging is a quick, convenient, and discrete way to keep in contact with your friends and loved ones that will keep you from burning extra minutes in your cell phone plan each month.

Text messaging is also known as SMS, or short message service, in the technical world. Cell phone users simply refer to them as text messages, or texts. And the popularity of the service has increased three fold over the past year in the United States alone. SMS permits the sending and receipt of text messages between cell phones and other handheld devices, such as PDAs.

Sending a text message to someone's phone is pretty simple. You simply choose the messaging feature on your cell phone, input the recipient’s phone number, and then type your message. Once you are finished typing your message, then you simply choose the send option and your message is sent. Many plans even allow you to send messages from your phone directly to an email address.

In case you are wondering, text messaging is usually a pretty affordable feature. Mobile phone companies may charge $0.10 or less per text message to send and receive text messages. This does not count towards your minutes usage and there is no additional charge.

To save even more when you use this feature, you may choose to add on a text messaging package to your current cell phone plan. Most text plans are relatively inexpensive and can be added for as little as $2.99, depending on how many messages you plan to send each month. Check with your cell phone carrier for messaging plans offered for your cell phone.

Cell phone companies count all messages that you send or receive, whether you read them or not. Messages can be up to 160 characters in length. If you receive a longer message, each 160 characters counts as a separate text message.

You can also use the text messaging feature on your cell phone to receive news alerts, ringtones, and more. However, this is normally classified as premium content and requires a subscription, which is an additional charge.

You may have even seen where many companies and television programs are using text messaging for entertainment purposes, such as voting and entering competitions. It is also used by many to play interactive games. You should keep in mind that you are charged extra for using text messaging in this manner, though.

So go ahead, start cell phone text messaging instead of idly wasting your cell phone minutes on things that can be said just as easily, and more cheaply, using text messaging.

Camera Cell Phones

These days, a good many cell phones come with a camera built right into the phone itself. Thus, these phones are called camera phones. These built in cameras are hardly noticeable and are unobtrusive to the cell phone user. Camera cell phones are hugely popular and their sales have even surpassed those of regular digital cameras.

Just as with your standard digital camera, resolution on camera phones varies. However, you can achieve virtually the same resolution on a VGA camera phone that you can achieve with a less expensive digital camera.

With current technology, camera phones are continuously being improved and upgraded. With some of the newer phones, picture quality is almost as good as some of the mid level digital cameras.

Competition among camera cell phone makers is fierce, and this is a good thing for consumers. Cell phone manufacturers continuously output better and cheaper camera phones, which gives you a wider range to choose from if you are considering a camera cell phone.

When shopping for your new camera phone, be sure to shop around and compare models, as features vary from phone to phone. Some features that you can choose from are flash, digital zoom and color adjustment. Some phones will also allow you to take self portraits.

Along with the camera feature on these cell phones, you may also be able to use the “photo caller id” feature. When someone calls you, the picture that you have stored in your phone for that person appears on the screen when the phone rings.

Other phones include the option to capture short video clips. In addition to taking photos, camera phones with video capability allow you to record short videos from your phone. This type of camera phone is rapidly increasing in popularity.

So, you have gone out and purchased a camera phone. The camera feature is great but you may be wondering what you will use it for. Besides using your phone to take the normal pictures you might take on a daily basis, there are numerous uses for your camera phone.

For example, if you are having a difficult time deciding on a clothing purchase, you might take a picture and send it to a friend for her opinion. Or suppose you are in a minor auto accident. Simply whip out your handy camera phone to take pictures of the damage and to keep track of the facts. If you are the forgetful sort, you might even decide to take a picture of the row and section where parked your car at a shopping center or in a garage.

Once you decide to buy a camera cell phone, you will invent hundreds of uses that may have never previously crossed your mind. And it only takes a second to snap a quick photo with your camera cell phone.

Tuesday 12 July 2011

An Overview of Halo Chemicals


Halo chemicals are compounds that contain halogens, one of the group of elements that includes fluorine, chlorine, bromine, iodine, astatine, and the as-yet undiscovered un unseptium (the existence of the latter element has been shown, but it has not yet been synthesized).

Chemical and Physical Properties of Halogens and Halo chemicals

All of the elements in the halogen group are characterized by their extremely high state of reactivity. All halogen atoms have an outer shell that contains seven electrons, and therefore is one electron short of being a full shell. This means that halogen atoms can gain the electron by reacting with other elements, which in turn makes halogens extremely reactive.

This high reactivity means that it is extremely rare to find halogens in their pure elemental form outside the laboratory. In nature, halogens are typically found as halide salts, and all "pure" halogens commonly exist as diatomic molecules, meaning that two atoms of a given halogen are bonded together.

Fluorine, for example, is so highly reactive that it can form compounds with several of the heavier noble gases, which are well-known for being largely inert. The only elements that fluorine cannot react with are the highly inert light noble gases helium, neon, and argon. Fluorine can also attack other types of inert material, such as glass.

All halogens can form compounds with hydrogen, each forming a strong acid called a hydrogen halide. Halogens can also react with each other, forming compounds called inter halogens.

Halogens are also used to create halo carbons. These are substances with one or more carbon atoms that are linked with one or more halogen atoms. The chemical reaction between carbon and halogen atoms produces strong chemical bonds called covalent bonds, which are not easily broken once formed.

Past and Present Uses of Halo chemicals

 have an extremely wide range of uses, and fluoro chemicals alone are used in a variety of different ways.

Halo carbons have been used as solvents, adhesives, sealants, pesticides, herbicides, fungicides, and refrigerants, and have been used to create plastics and plasticizers (meaning they are added to substances to increase certain desirable physical properties).

Some halo chemicals that were once widely utilized are no longer in use, due to concerns over toxicity, or environmental issues. Examples include chlorofluorocarbons (CFCs) such as Freon, many types of fluorocarbons (which were once commonly used industrial solvents, but now have a much more limited range of uses), and solvents such as carbon tetrachloride and trichloro ethane, which were once available for public use but are now tightly regulated.

Two particularly well-used halogens are chlorine and fluorine, both of which are added to drinking water in many countries-chlorine as an antibacterial and anti fungal agent, and fluorine (in the form of fluoride) to strengthen tooth enamel and help prevent tooth decay.

Many substances-including pharmaceuticals, and agricultural substances such as pesticides and herbicides-also benefit in terms of factors such as stability and potency from the addition of one or more halogen atoms. The addition of a halogen is carried out in a process called halo genation (this process can actually be done in several different ways, each involving a series of specific chemical steps). In many cases, the halogen added is fluorine.

In fact, fluorine is a component of a surprisingly large percentage of modern pharmaceuticals. The addition of fluorine atoms increases the stability and potency of many drugs, and fluorine is currently added to a wide variety of pharmaceuticals, including anesthetics, antacids, anti fungal and antibiotic medicines, antidepressants, steroids, cholesterol lowering agents, and anticancer chemotherapeutic drugs.

Bluetooth Technical Operations

Bluetooth is a high speed, low powered wireless link technology that's designed to connect phones or other portable equipment together with little to no work required by the user. Unlike infrared, Bluetooth doesn't require line of site positioning to work.

Current prototype circuits are contained on a board that is 0.9 cm square, with a much smaller circuit board being developed.

When one Bluetooth device comes in contact with another, they will automatically exchange addresses and details of capability. Then, they can establish a 1 MB link with security that they will use as required. The protocols involved with handle both data and voice, with a very flexible topography.

The technology achieves its goal by embedding tiny, non expensive short range tranceivers into the devices available today. The radio operates on the 2.45 GHz frequency band, and supports up to 721 KBps, along with three voice channels.

Each devices offers a unique 48 bit address from the IEEE 802 standard, with the connections being point to point or multipoint. The max range is 10 meters, although it can be extended to 100 meters by increasing the power. The devices are also protected from radio interference by changing their frequencies, also known as frequency hopping.

What's important, is the fact that Bluetooth devices won't drain battery life. The specification targets power consumption of the device, limiting the drain on the battery. The radio chip will consume only 0.3mA in stand by mode, which is less than 5% of the power that standard phones use.

Bluetooth will also guarantee security at the bit level. The authentification is controlled by the user via a 128 bit key. The radio signals can be coded with anything up to 128 bit. With the frequency hopping, Bluetooth is already very hard to listen into.

The baseband protocol is a combination of both circuit and packet switches. Slots can be reserved for synchronous packets as well. Each packet will be transmitted in a different hop frequency. Normally, a packet covers a single slot although it can be extended to cover up to five slots.

Bluetooth can also support data channels of up to three simultaneous voice channels. Therefore, it's possible to transfer the data while you talk at the same time. Each individual voice channel will support 64 KB.

From a technical standpoint, Bluetooth is very different indeed. It's the best wireless method in the world, surpassing even infrared. For communication on the go, Bluetooth is indeed very hard to compete with.

Steam Flow Meter Used For Industrial Applications

Optical sensors used in a steam flow meter can provide safer, more accurate measurements without the need for electricity or wires, reducing the potential for fire or explosions. Accuracy in volume and velocity measurements is said to be within one half of one percent and new models claim to not only be able to measure the flow of steam but also the amount of water present.

A few steam flow meters can take measurements in both directions in applications where flow may have to be reversed for maintenance of safety reasons as well as measuring saturated steam due to the extreme temperatures involved.

With temperature of steam being extremely high, intrusive flow measuring equipment often failed due their exposure to the high temperatures. By being able to install a non-intrusive steam flow meter that can measure not only the flow, but also the saturation of the steam can be helpful in many applications. The saturation measurements show what percent of the steam is in water form.

Steam Measured By Volume Not Mass

A typical steam flow meter will give the measurement in volume instead of mass, as the pressure of the steam will affect the mass and accuracy is nearly impossible to attain. If the steam pressure doubles, the density will double and its mass will double, however the volume will remain constant. In most cases a pressure valve will restrict the flow at the end use to maintain a constant pressure. This however may increase pressure at the boiler.

Proper maintenance is required on all steam generating equipment to insure the accuracy of the steam flow meter readings. Boilers are by nature in a harsh environment and rust and corrosion are common causes of breakdowns. Intrusive type of steam flow meters can also be affected by this environment. Monitoring of the equipment is a must, as is frequent calibration of the metering device to insure accurate readings at the process end.

A miscalculated steam flow meter could allow too much steam, consequently too much pressure to build up and damage critical equipment. Steam is produced for the purpose of a specific process. Whether it's to provide heat or power to a source, therefore the amount of steam released to the process needs to be accurately measured.

Since most steam flow meters utilize orifice plates in their measurements, they must be check frequently due to their penchant to wear and give false or inaccurate readings. Simple precautions and preventive maintenance can reduce costly repairs and unscheduled down time.

Board-by-Board Optimization

use as each board type enjoys its own thermal profile in your surface mount oven, each board type also enjoys its own board-wave parameters in your wave machine

The optimal dwell time for that board was found to be 3.6 seconds, in contrast to 2.8 seconds for the first board. As you can see, the “dwell time profiles” of the two boards are different. This process resulted in dramatically lower defect rates for the second board studied (which had also been previously run at 1.0 seconds), although never quite as low as the new baseline which was attained for the first board. This strongly indicates the presence of sources of defects unrelated to dwell time, for example non-optimal immersion depth or design problems.

Immersion Depth

Changing your immersion depth changes your contact length and dwell time. This makes the direct and accurate measurement of immersion depth critical. Your pump speed produces a wave height (although this can diminish as your solder pot empties of solder), but the actual immersion depth of your boards depends on several factors, including solder pot height, how they sit in the fingers, if your fingers are bent, broken or crooked, the angle of your conveyor and whether or not pallets are used.

Yet controlling your immersion depth - measuring it and keeping it consistent - is only one piece of the puzzle. Another is: At which immersion depth is your board quality optimized? This point is illustrated by figure 4. See that the defect rate of the board represented by the blue bars is optimized over a different range (48 mil, or even 36 to 60 mil) than the board represented by the yellow bars (at 24 to 36 mil). So, different board types benefit most from different immersion depths.
Quantifying Cost Benefits

Prior to this study, yield loss was tracked on a monthly basis as a measure of the cost of production failures. Production volume for the board studied was 11,000 per month.

1.) With the implementation of optimal dwell time procedures using the described device, yield loss went from 3.0% (330 boards) to 1.6% (176 boards) in the first month of daily use.

2.) This meant a reduction in yield loss of 154 boards per month. For a 30 day month, this means 5.13 boards per day.

3.) At 0 for the cost of each board, cost reduction based on improved yield loss alone was ,200 per month, which annualizes to 4,400.

4.) That means that the return on investment on the device used in the study was less than five days.

Conclusion: A seemingly small daily improvement in wave solder quality meant fast, very large, measurable monthly and annual cost savings. These figures do not even account for the valuable savings from benefits like reduced rework and field failures, less downtime and increased throughput, each of which in its own right can be more valuable than the rapid savings on yield loss.

An Overview of Specialty Fluorochemicals

Fluorine has a number of chemical properties that make it particularly desirable for a wide variety of different industrial, commercial, and even medical applications. In particular, it is the most electronegative and the most highly reactive of all the elements, and readily forms compounds with all elements except for the three lightest noble gases. One particularly useful property of fluorine is that it forms strong and stable covalent bonds with carbon.
Due to these important and highly useful chemical properties, specialty fluorochemicals have numerous applications in a range of industries. The addition of fluorine or fluorine substituents improves the desirable qualities of an amazingly wide variety of compounds including pharmaceuticals, plastics, elastomers, and surfactants.
One of the most well-known uses of fluorine is the addition of fluoride to drinking water and toothpastes, to strengthen tooth enamel and help prevent tooth decay. There are many more highly specific uses of fluorine and specialty fluorochemicals, most of which are concentrated in the industrial, agricultural, and pharmaceutical industries.
Types and Uses of Specialty Fluorochemicals
Agricultural Uses: The addition of fluorine to many agricultural herbicides, pesticides, and fungicides improves the potency and therefore reduces the required application rate of these substances.
Photoresists: These polymers are used in semiconductor lithography. The addition of fluorine or fluorinated substituents to photoresists improves desirable chemical and physical properties.
Surfactants: Fluorine is a key component of surfactants and related compounds such as stain repellants.
Dyes: Adding fluorine or fluorinated substituents to many dyes improves their chemical and light resistance, and also their fixation yield.
Liquid Crystals: Adding fluorine to liquid crystal for use in display devices improves desirable chemical and physical properties such as the viscosity and miscibility of the liquid.
Plastics and Elastomers: With the addition of fluorine, these substances become more chemically and thermally stable. Due to these desirable properties fluoroplastics and fluoroeslastomers are used in a variety of ways, including in wiring insulation, gaskets and seals, hoses, and laboratory equipment.
Ion-Exchange Membranes: The use of fluorinated polymers allows ion-exchange membranes to be used in harsh environments, as the addition of fluorine improves the chemical and thermal stability of the membranes.
Custom-made Fluorochemicals: One particularly advantageous aspect of fluorine is that it can be added to a wide variety of chemical substances to increase stability, potency, and other desirable qualities. This means it is often possible to create custom-made specialty fluorochemicals.
A Closer Look at Fluorocarbons
Fluorocarbons are a particular type of fluorochemicals in which fluorine atoms are covalently bonded to carbon atoms in varying numbers and configurations. These covalent bonds are strong and stable, and this has been a major reason for the widespread of use fluorocarbons for a variety of applications. Fluorocarbons have been used as lubricants, propellants, refrigerants, solvents, and in water and stain-repellent products.
Concern over the slow environmental degradation of fluorocarbons has led to reduced usage of many of these substances. Some, such as carbon tetrachloride, were once available for public use, but are now much more tightly regulated. Most fluorocarbon solvents now have a much more limited range of industrial uses.
Some fluorocarbons (such as Freon) have a particularly bad reputation, however, due to their use as refrigerants and propellants. These have commonly contained chlorine in addition to fluorine. While the strong fluorine-carbon bonds make these substances highly resistant to environmental degradation, the addition of chlorine makes them highly reactive and destructive to the earth’s ozone layer. For this reason, the use of chlorofluorocarbons has been largely discontinued.
Despite environmental concerns, some fluorocarbons (such as fluoroplastics and fluoroeslastomers) are still in common use. One example is Teflon, which is a very common component of non-stick cookware.
The Use of Fluorine in Pharmaceuticals
One increasingly widespread application of specialty fluorochemicals is in the pharmaceutical industry, in which the ability of fluorine to improve the existing properties of other chemicals makes it enormously useful.
Simply by adding fluorine, the pharmacological properties of a drug can be improved in potency quite significantly, allowing for the use of lower doses to achieve the same effect as was previously gained.
Aside from this highly desirable property, another important advantage of adding fluorine to pharmaceuticals is that the shape of the resulting fluorochemical is largely unchanged. This is particularly important because the bioactivity of many drugs is highly dependent on the shape of the chemical compound.
One drawback, however, is the fact that the addition of fluorine improves the stability of pharmaceuticals. While this is an enormous advantage for most other specialty fluorochemical applications, in the pharmaceutical industry this is not always the case, because in some cases, improving the stability of a drug can reduce its metabolic degradation.
Currently, up to 50% of all modern pharmaceuticals contain fluorine. These include anesthetics, antidepressants, antifungals and antibiotics, antacids, cholesterol lowering agents, steroids and other anti-inflammatory agents, and certain types of anticancer chemotherapeutic drugs.
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About the Author
Stephanie Larkin is a freelance writer who writes about issues and topics pertaining to the use of chemicals such as Fluorochemicals