If you have more than one computer at home, you are probably better off connecting them or networking them together to use the same resources and receive the same internet connection. A home network is very easy to build. Here are some tips.
There are two main types of home networks, wired and wireless. While wired home networks are popular, but they require you to run wires from one computer to another. You might have to drill holes in a wall or run wire under the carpet.
If you don’t want cords running all over the place, you can easily get rid of them with a wireless home network. Wireless home networks are extremely simple to set up. You only need a wireless router and a wireless networking card for each additional computer you would like to hook up. Most wireless networks can send and receive data lightning fast at megabytes per second.
Wireless networks are extremely inexpensive, you can hook up a few computers for less than $200. The great part of wireless networks is that all computers on the wireless network can use the same internet or other resources such as a scanning machine and printer. So if you are looking for a great way to share data and resources among your home computer, choose to build a home network.
More information is available at http://www.home-00.info
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1. Make sure that your computer is connected to the router via the Ethernet or a wireless WiFi connection.
2. Now, in your favorite web browser go to the address: http://www.192.168.1.1
3. Usually in the older versions of Linksys routers, there will only be a password (admin) and no need to input a username. However the recent newer models of the Linksys router have “admin” as both the default username and the password.
4. Below are a few sample modes and their default usernames and passwords:
A. Default Usernames Known:
Linksys BEFW11S4: admin
Linksys WRT54G: admin
Linksys Comcast: Comcast
Linksys EtherFast Cable/DSL Ethernet: Administrator
The rest of the Linksys routers: [not required]
B. Default Passwords Known:
Linksys BEFW11S4: [not required]
Linksys Comcast: 1234
The rest of the Linksys routers: admin
In the case that you forgot your Linksys router password, you can always reset the outer by clicking the reset button at the back or at the bottom of the router.
NEW YORK (AP) — Lululemon Athletica Inc. named Facebook executive Emily White to its board, saying her social media and e-commerce experience complements the yoga-wear retailer's online efforts.
The Canadian company said Friday that White's addition expanded the board to 10 members.
White is senior director of local and mobile partnerships at Facebook, which she joined in 2010. Before that, she served in several e-commerce positions at Google from 2001 to 2010.
"Emily brings a wealth of knowledge regarding e-commerce and social media to our board in a time when our customers are utilizing these communication channels more than ever to both shop and enrich their lives," Lululemon Chairman Chip Wilson said.
Lululemon offers shopping on its site as well as videos and a blog about yoga, running and other topics.
It's been one of the hottest chains in retailing. The popularity of its high-priced yoga pants and tank tops — the pants run about $100 — has helped shares more than double in the past 12 months.
Shares rose $1.22, or 2.4 percent, to $51.54 in premarket trading.
Read More:
http://news.yahoo.com/lululemon-names-facebook-exec-emily-white-board-141303226.html
The Canadian company said Friday that White's addition expanded the board to 10 members.
White is senior director of local and mobile partnerships at Facebook, which she joined in 2010. Before that, she served in several e-commerce positions at Google from 2001 to 2010.
"Emily brings a wealth of knowledge regarding e-commerce and social media to our board in a time when our customers are utilizing these communication channels more than ever to both shop and enrich their lives," Lululemon Chairman Chip Wilson said.
Lululemon offers shopping on its site as well as videos and a blog about yoga, running and other topics.
It's been one of the hottest chains in retailing. The popularity of its high-priced yoga pants and tank tops — the pants run about $100 — has helped shares more than double in the past 12 months.
Shares rose $1.22, or 2.4 percent, to $51.54 in premarket trading.
Read More:
http://news.yahoo.com/lululemon-names-facebook-exec-emily-white-board-141303226.html
Chromatography is a method used to separate different components of a mixture. There are different types of chromatography, but all of them are based on the same principle: the different molecules or ions in the mixture will interact differently with the stationary phase of the chromatograph, and get separated in the process. The different techniques of chromatography use different substances as the stationary and mobile phases. Chromatography can either be analytical or preparative. Analytical chromatography is used for determining the relative proportions of the different components in the mixture, while the separation of the different components is what preparative chromatography is used for.
Chromatography techniques are generally classified on the basis of the mechanism of separation. The types of chromatography, based on the mechanism of separation, are adsorption chromatography, partition chromatography, ion exchange chromatography, molecular exclusion chromatography, and affinity chromatography. Paper chromatography is based on the principle of partition chromatography.
Uses of Paper Chromatography
Paper chromatography is a simple chromatography technique which has many applications. Its main advantage is that it is not very expensive to perform, and provides clear results. Given below are some important uses of paper chromatography.
Obtain Pure Compounds
Paper chromatography is used to obtain pure compounds from a mixture. This is done by cutting out and redissolving the patterns formed by each constituent. Also, this technique can be effectively used to remove impurities from chemical compounds. Due to the process of paper chromatography, the impurities get separated from the compound and the pure compound can be obtained.
Qualitative Analysis of Drugs
Paper chromatography is one of the methods of qualitative analysis, to analyze or separate the different constituents of a mixture. It is a useful tool for separating polar as well as nonpolar solutes. Pharmaceutical companies use this technique to analyze the different compounds in drugs.
Forensic Science
Paper chromatography is useful in the field of forensic science, for investigation of crime. Samples from crime scenes are collected to be anaylzed and identified, using this technique.
Separating Colored Pigments
Paper chromatography is an effective technique for separating colored pigments from a mixture. Each pigment gets separated and rises up to a particular level on the chromatography paper.
Determining the Pollutants in Water
This technique is used to determine the pollutants or impurities in water bodies like rivers and lakes, by analyzing a small sample from the water body.
Analyzing Complex Mixtures
Paper chromatography is used to detect the presence of, or identify certain organic compounds such as carbohydrates and amino acids, from a complex mixture of organic compounds.
Pathology
Pathological laboratories use paper chromatography to detect the presence of alcohol or chemicals in blood. The fact that paper chromatography requires small samples, is very useful in pathological testing and diagnostics.
How Does Paper Chromatography Work
To understand the principle of paper chromatography, we must learn what is partition chromatography. As the name suggests, partition chromatography is a method of separating the components of a mixture in which the constituents of the mixture are partitioned or separated between two liquid phases, one of which is supported by a solid and is termed as the stationary phase. The other liquid phase is the solvent in which a small amount of the mixture (that is to be separated) is dissolved. In paper chromatography, the solid in question is a filter paper, and the stationary phase is water in the pores of the filter paper. The following are the steps to perform paper chromatography.
Step 1: Take a long rectangular piece of filter paper and draw a straight line on it using a pencil, a few centimeters above one of its shorter edges. This is your start line. Place a drop of the mixture on the start line, using a capillary tube.
Step 2: Take a glass jar and pour a small amount of the solvent liquid into it. Now, place the filter paper inside the glass jar such that the part of it below the start line, is submerged in the solvent. Do not disturb the setup and you shall see that the solvent in the jar slowly rises up due to the capillary action of the paper. Wait for around 15-20 minutes, till the solvent nearly reaches the top of the paper.
Step 3: Remove the filter paper from the jar and mark the highest point on the filter paper till which the solvent has risen. You shall see that the different components of the mixture have been carried to different levels, by the solvent. In the above diagram, you can see two colored spots formed by two different solutes, A and B. This is due to the difference in the affinity of the solutes present in the mixture, to the filter paper (stationary phase). So, while one solute (solute B) is easily carried farther away by the solvent, the other is not. This results in the solutes getting separated from the mixture.
Step 4: When the filter paper has dried, note the distance covered by each constituent from the start line. Now, calculate the retardation factor (Rf value) by the following formula. This value can never be more than 1, which implies that a solute can never travel ahead of the solvent.
Retardation Factor (Rf) = Distance traveled by the solute from the start lineDistance traveled by the solvent from the start line
Note: If the spot formed by a component is irregular, you need to measure the distance from the middle of the spot to the start line.
This was all about paper chromatography and its uses. However, while performing an experiment on paper chromatography, you need to follow each step carefully in order to get the desired results.
from:
http://www.buzzle.com/articles/paper-chromatography-uses.html
Chromatography techniques are generally classified on the basis of the mechanism of separation. The types of chromatography, based on the mechanism of separation, are adsorption chromatography, partition chromatography, ion exchange chromatography, molecular exclusion chromatography, and affinity chromatography. Paper chromatography is based on the principle of partition chromatography.
Uses of Paper Chromatography
Paper chromatography is a simple chromatography technique which has many applications. Its main advantage is that it is not very expensive to perform, and provides clear results. Given below are some important uses of paper chromatography.
Obtain Pure Compounds
Paper chromatography is used to obtain pure compounds from a mixture. This is done by cutting out and redissolving the patterns formed by each constituent. Also, this technique can be effectively used to remove impurities from chemical compounds. Due to the process of paper chromatography, the impurities get separated from the compound and the pure compound can be obtained.
Qualitative Analysis of Drugs
Paper chromatography is one of the methods of qualitative analysis, to analyze or separate the different constituents of a mixture. It is a useful tool for separating polar as well as nonpolar solutes. Pharmaceutical companies use this technique to analyze the different compounds in drugs.
Forensic Science
Paper chromatography is useful in the field of forensic science, for investigation of crime. Samples from crime scenes are collected to be anaylzed and identified, using this technique.
Separating Colored Pigments
Paper chromatography is an effective technique for separating colored pigments from a mixture. Each pigment gets separated and rises up to a particular level on the chromatography paper.
Determining the Pollutants in Water
This technique is used to determine the pollutants or impurities in water bodies like rivers and lakes, by analyzing a small sample from the water body.
Analyzing Complex Mixtures
Paper chromatography is used to detect the presence of, or identify certain organic compounds such as carbohydrates and amino acids, from a complex mixture of organic compounds.
Pathology
Pathological laboratories use paper chromatography to detect the presence of alcohol or chemicals in blood. The fact that paper chromatography requires small samples, is very useful in pathological testing and diagnostics.
How Does Paper Chromatography Work
To understand the principle of paper chromatography, we must learn what is partition chromatography. As the name suggests, partition chromatography is a method of separating the components of a mixture in which the constituents of the mixture are partitioned or separated between two liquid phases, one of which is supported by a solid and is termed as the stationary phase. The other liquid phase is the solvent in which a small amount of the mixture (that is to be separated) is dissolved. In paper chromatography, the solid in question is a filter paper, and the stationary phase is water in the pores of the filter paper. The following are the steps to perform paper chromatography.
Step 1: Take a long rectangular piece of filter paper and draw a straight line on it using a pencil, a few centimeters above one of its shorter edges. This is your start line. Place a drop of the mixture on the start line, using a capillary tube.
Step 2: Take a glass jar and pour a small amount of the solvent liquid into it. Now, place the filter paper inside the glass jar such that the part of it below the start line, is submerged in the solvent. Do not disturb the setup and you shall see that the solvent in the jar slowly rises up due to the capillary action of the paper. Wait for around 15-20 minutes, till the solvent nearly reaches the top of the paper.
Step 3: Remove the filter paper from the jar and mark the highest point on the filter paper till which the solvent has risen. You shall see that the different components of the mixture have been carried to different levels, by the solvent. In the above diagram, you can see two colored spots formed by two different solutes, A and B. This is due to the difference in the affinity of the solutes present in the mixture, to the filter paper (stationary phase). So, while one solute (solute B) is easily carried farther away by the solvent, the other is not. This results in the solutes getting separated from the mixture.
Step 4: When the filter paper has dried, note the distance covered by each constituent from the start line. Now, calculate the retardation factor (Rf value) by the following formula. This value can never be more than 1, which implies that a solute can never travel ahead of the solvent.
Retardation Factor (Rf) = Distance traveled by the solute from the start lineDistance traveled by the solvent from the start line
Note: If the spot formed by a component is irregular, you need to measure the distance from the middle of the spot to the start line.
This was all about paper chromatography and its uses. However, while performing an experiment on paper chromatography, you need to follow each step carefully in order to get the desired results.
from:
http://www.buzzle.com/articles/paper-chromatography-uses.html
People have more flexible time due to wireless network. Thanks to the invention of wireless. People can now work from home while taking care of their kids or doing house works. No more stress from traffic jam anymore. Is this great?
Well, there is something you should realize. Working from home while using a wireless local area network (WLAN) may lead to theft of sensitive information and hacker or virus infiltration unless proper measures are taken. As WLANs send information over radio waves, someone with a receiver in your area could be picking up the transmission, thus gaining access to your computer. They could load viruses on to your laptop which could be transferred to the company's network when you go back to work.
Believe it or not! Up to 75 per cent of WLAN users do not have standard security features installed, while 20 per cent are left completely open as default configurations are not secured, but made for the users to have their network up and running ASAP. It is recommended that wireless router/access point setup be always done though a wired client.
You can setup your security by follow these steps:
1. Change default administrative password on wireless router/access point to a secured password.
2. Enable at least 128-bit WEP encryption on both card and access point. Change your WEP keys periodically. If equipment does not support at least 128-bit WEP encryption, consider replacing it. Although there are security issues with WEP, it represents minimum level of security, and it should be enabled.
3. Change the default SSID on your router/access point to a hard to guess name. Setup your computer device to connect to this SSID by default.
4. Setup router/access point not to broadcast the SSID. The same SSID needs to be setup on the client side manually. This feature may not be available on all equipment.
5. Block anonymous Internet requests or pings. On each computer having wireless network card, network connection properties should be configured to allow connection to Access Point Networks Only. Computer to Computer (peer to peer) Connection should not be allowed.
Enable MAC filtering. Deny association to wireless network for unspecified MAC addresses. Mac or Physical addresses are available through your computer device network connection setup and they are physically written on network cards. When adding new wireless cards / computer to the network, their MAC addresses should be registered with the router /access point. Network router should have firewall features enabled and demilitarized zone (DMZ) feature disabled.
All computers should have a properly configured personal firewall in addition to a hardware firewall. You should also update router/access point firmware when new versions become available. Locating router/access point away from strangers is also helpful so they cannot reset the router/access point to default settings. You can even try to locate router/access point in the middle of the building rather than near windows to limit signal coverage outside the building.
There is no guarantee of a full protection of your wireless network, but following these suggested tips can definitely lessen your risk of exposing to attackers aiming at insecure networks.
Well, there is something you should realize. Working from home while using a wireless local area network (WLAN) may lead to theft of sensitive information and hacker or virus infiltration unless proper measures are taken. As WLANs send information over radio waves, someone with a receiver in your area could be picking up the transmission, thus gaining access to your computer. They could load viruses on to your laptop which could be transferred to the company's network when you go back to work.
Believe it or not! Up to 75 per cent of WLAN users do not have standard security features installed, while 20 per cent are left completely open as default configurations are not secured, but made for the users to have their network up and running ASAP. It is recommended that wireless router/access point setup be always done though a wired client.
You can setup your security by follow these steps:
1. Change default administrative password on wireless router/access point to a secured password.
2. Enable at least 128-bit WEP encryption on both card and access point. Change your WEP keys periodically. If equipment does not support at least 128-bit WEP encryption, consider replacing it. Although there are security issues with WEP, it represents minimum level of security, and it should be enabled.
3. Change the default SSID on your router/access point to a hard to guess name. Setup your computer device to connect to this SSID by default.
4. Setup router/access point not to broadcast the SSID. The same SSID needs to be setup on the client side manually. This feature may not be available on all equipment.
5. Block anonymous Internet requests or pings. On each computer having wireless network card, network connection properties should be configured to allow connection to Access Point Networks Only. Computer to Computer (peer to peer) Connection should not be allowed.
Enable MAC filtering. Deny association to wireless network for unspecified MAC addresses. Mac or Physical addresses are available through your computer device network connection setup and they are physically written on network cards. When adding new wireless cards / computer to the network, their MAC addresses should be registered with the router /access point. Network router should have firewall features enabled and demilitarized zone (DMZ) feature disabled.
All computers should have a properly configured personal firewall in addition to a hardware firewall. You should also update router/access point firmware when new versions become available. Locating router/access point away from strangers is also helpful so they cannot reset the router/access point to default settings. You can even try to locate router/access point in the middle of the building rather than near windows to limit signal coverage outside the building.
There is no guarantee of a full protection of your wireless network, but following these suggested tips can definitely lessen your risk of exposing to attackers aiming at insecure networks.
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