Up until now, the best way to MacGyver a battery has been to stick a copper wire and a galvanized nail into a lemon (or an apple, or a potato, or…). Fruit or vegetable batteries produce a respectable voltage (around a volt) but only a tiny amount of current- not enough to light a flashlight bulb.
Now there’s the “burrito” battery. It produces 400 times as much current as a lemon battery- enough to actually light a little holiday lightbulb, or run a small DC motor. All you need is some duct tape. And a piece of aluminum foil, some table salt, a paper towel, some activated charcoal, and some copper wire to use for leads. You make a “burrito” with the aluminum foil as the tortilla. Line the foil with the paper toil, moistened with salt water. Fill the burrito with activated charcoal, also moistened saturated salt water. Sink one copper lead into the charcoal and duct-tape the other to the aluminum foil and voila! You should have about 1 V, with 100 milliamperes of current. Attach several cells in parallel for more current, and in series for more voltage!
You can find a step-by-step guide for building the battery at http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html. The authors of that page have published a nice classroom activity sheet to go along with the battery in the December 2007 issue of the Journal of Chemical Education (M. Tamez, J. H. Yu, J. Chem. Ed. 2007, 84, 1936A-1937A).
How does it work?
All batteries work by running chemical reactions that release electrons in one place, and capture electrons in another. When you run a wire between these two places, an electric current flows through it. You can tap off some of the energy of that current to light a bulb or drive a motor.
In the aluminum-air battery, the aluminum in the foil is the electron source. Aluminum on the surface of the foil reacts with hydroxide ions in the salt water to form aluminum hydroxide. Every aluminum atom that reacts releases three electrons into the foil:
Al(s) + 3OH-(aq) –> Al(OH)3(s) + 3e-
This is called an oxidation (a reaction that involves a loss of electrons).
Air absorbed in the nooks and crannies of the activated charcoal acts as the electron sink. Specifically, oxygen gas captures electrons using this half reaction:
O2(g) + 2H2O(l) + 4e- –> 4OH-(aq)
This is called a reduction (a reaction that involves a gain of electrons). Notice that the activated charcoal doesn’t actually do anything in this reaction. It just provides a nice place for the reaction to occur. It has a high surface area, so it is in contact with a lot of oxygen molecules. It is also able to shuttle electrons from the copper wire to oxygen absorbed on its surface.
The battery won’t work unless the oxidation and reduction reactions can work together. By itself, the foil will build up a positive charge as it loses electrons. It’s hard to pull negatively charged electrons from the positively charged foil, so the oxidation reaction will stop if the charge on the foil isn’t neutralized somehow.
Similarly, if you keep dumping electrons into the oxygen in the charcoal, a negative charge would build up. The reduction reaction will shut down, because you couldn’t force any more negatively charged electrons onto the negatively charged surface of the charcoal.
This is where the wet, salty paper towel comes in. The towel acts as a salt bridge that prevents charge from building up on either the foil or the charcoal. Chloride ions in the salt (Cl-) move towards the foil, neutralizing the positive charge buildup there. Sodium ions (Na+) migrate towards the charcoal, neutralizing the negative charge buildup caused by the reduction.
Written by senese on November 20th, 2007 with comments disabled.
Read more articles on battery and chemical education and chemistry and demo and demonstration and electrochemistry and how to and macgyver.
These steps will take you through preparing a USB ram drive (thumb drive, pen drive, or how ever you care to refer to it) so that you may use it to boot your Windows PE image without the need of a hard drive (or bootable CD/DVD). These steps assume you have already generated your Windows PE folder structure where you would typically burn it to an ISO image.
1) Run diskpart from command prompt running as administrator (right click the command prompt icon and choose “Run As Administrator”)
2) Type the command: list disk to see the available disks and note the one that represents your USB thumb drive (more…)
bootable cd,
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drive pen,
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iso image,
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usb ram drive,
Windows,
windows pe
Written by Jason on November 20th, 2007 with comments disabled.
Read more articles on Installation and bootable cd and command prompt and diskpart and drive pen and folder structure and hard drive and iso image and thumb drive pen drive and usb ram drive and windows and windows pe.
During the betas of Windows Vista,
the final set of sample logon pictures had yet to be determined,
so a bunch of placeholder bitmaps were created.
These placeholders consisted of the letters FPO in a box. FPO is a standard term in desktop publishing Read More......(
read more)
Written by The Old New Thing : History on November 20th, 2007 with comments disabled.
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Is it hard to be a hacker? How do I become a hacker? I want to learn more about hacking! Those are the things that I often hear or see on forums. Somebody asked me the other day if I know how to hack a site and whether it’s hard or not. I’m no hacker, I’m just a journalist. However, Petko D. Petkov aka pdp is a world-renowned hacker who in his latest blog post describes how easy it can be for someone with just a bit of skill to hack into military and government sites - .mil and .gov that is.
He won’t give you the tools or tell you where to get them from, but he does explain how easy it is to exploit certain vulnerabilities. He says that the web is full of open CITRIX gateways and while he was performing some CITRIX testing he hacked a lot of GUIs and “played” around with .ICA files. (more…)
attackers,
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icas,
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Web,
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Written by Jason on November 20th, 2007 with comments disabled.
Read more articles on Internet and Web and Yahoo and attackers and citrix and google and great tools and guis and hack a site and how to hack and icas and pdp and port scans and world renowned.
Windows XP Service Pack 3 Release Candidate build is live. Microsoft is hammering away at the third and final service pack for Windows XP, and is making consistent headway in the matter. Truth be told, since the 2004 availability of XP SP2, and after the numerous delays of SP3 across 2006 and 2007, Service Pack 3 is long overdue. But at the same time, the refresh is getting closer and closer at a fast pace. Microsoft has in fact synchronized the development milestones of Windows Server 2008, formerly codenamed Longhorn, Windows Vista Service Pack 1 and Windows XP SP3.
The third service pack for XP was initially introduced as a Beta preview version concomitantly with Windows Vista SP1 pre-Beta in mid July 2007. Ever since that point, Vista SP1 and XP SP3 have been joined at the hip. In this regard, Vista SP1 moved into Beta stage at the end of September 2007, with XP SP3 Beta following closely behind in early October. Last week, Microsoft opened up the test driving process of Vista SP1 with a preview of the first Release Candidate to the service pack shipping to approximately 15,000 testers. (more…)
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Written by Jason on November 20th, 2007 with comments disabled.
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If you have ever tried out the Shared Computer Toolkit - or the newer Windows SteadyState toolkit, you probably know that Windows Vista has not been supported so far… But now it’s here - go get it:
Windows SteadyState 2.5 Beta
http://www.microsoft.com/downloads/details.aspx?FamilyId=4DE91D3A-69F4-4D7B-94B1-C69B8BE029F4&displaylang=en
Windows SteadyState 2.5 Beta Handbook
http://www.microsoft.com/downloads/details.aspx?familyid=D173452A-CE26-4F26-9C30-982F705F84D2&displaylang=en
Windows SteadyState 2.5 Beta Readme File
http://download.microsoft.com/download/E/2/F/E2F23589-E8E1-404F-9DAB-77F1CAE24153/ReadmeBeta.txt
Supported Operating Systems:
Windows Vista: Business/Home Basic/Starter/Ultimate/Enterprise/Home PremiumWindows XP: Home/Professional with Service Pack 2
Written by Jakob H. Heidelberg on November 20th, 2007 with comments disabled.
Read more articles on Shared Computer Toolkit and SteadyState and Windows Vista and Windows XP.
With Windows Vista, Microsoft has delivered an evolution in terms of user experience. Still, as the operating system suffers a decent amount of customization, improvements on the Redmond company’s original design are inevitable. And one of the aspects of Vista that could manage with a tad extra eye candy is the boot screen. Now on the adjacent image you can see a portion of the default Vista boot screen, which otherwise is pitch black. Well, nothing to get excited about there, but you have a few options to kick it up a notch.
First off, you can always dig up the Windows Vista hidden boot screen. All you have to do is make your way to the System Configuration Utility and enable the “No GUI Boot” option. Just follow this link in order to get additional details about how to unveil the hidden boot screen in your copy of Vista. The tweak is harmless but, at the same time, it is also limited to only one image consistent with the Aero theme. (more…)
boot logo,
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vista,
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winload
Written by Jason on November 20th, 2007 with comments disabled.
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Richard Campbell & Greg Hughes from RunAs Radio talks to my good friend Jeremy Moskowitz about Group Policy - who would have guessed, right 
Check it out here: http://www.runasradio.com/default.aspx?showNum=32
Written by Jakob H. Heidelberg on November 20th, 2007 with comments disabled.
Read more articles on Jeremy Moskowitz and group policy and radio and runas.
Hi,
This is a list of my articles on www.windowsecurity.com for reference - if you haven’t read them yet, please do so!
Group Policy related changes in Windows Server 2008 (Part 1: What are Starter GPOs?)
This article series deals with the new Group Policy features W2008 will bring, including GPMC v2 features and Group Policy Preferences.
http://windowsecurity.com/articles/Group-Policy-related-changes-Windows-Server-2008-Part1.html
Protect Public Computers with Windows SteadyState (Part 1)
This is an article series deals with the Windows SteadyState product and how to protect public computers using this toolkit.
http://windowsecurity.com/articles/Protect-Public-Computers-Windows-SteadyState-Part1.html
Configuring Granular Password Settings in Windows Server 2008 (Part 1 & 2)
This article series deals with how to set Granular Password Policies for WS2008 domains.
http://windowsecurity.com/articles/Configuring-Granular-Password-Settings-Windows-Server-2008-Part-1.html
http://windowsecurity.com/articles/Configuring-Granular-Password-Settings-Windows-Server-2008-Part2.html
Efficient Registry Cleanup
This article deals with Group Policy Startup scripts and why they are so powerful.
http://windowsecurity.com/articles/Efficient-Registry-Cleanup.html
Default Deny All Applications (Part 1 & 2)
This article series deals with Software Restriction Policies and how to implement SRP in a corporate environment.
http://windowsecurity.com/articles/Default-Deny-All-Applications-Part1.html
http://windowsecurity.com/articles/Default-Deny-All-Applications-Part2.html
How to Force Remote Group Policy Processing
This article shows how to update Group Policy settings on remote computers using different approaches.
http://windowsecurity.com/articles/How-Force-Remote-Group-Policy-Processing.html
Managing Windows Vista Group Policy (Part 1, 2 & 3)
This article series deals with the new things in Group Policy land after Windows Vista joined the world.
http://windowsecurity.com/articles/Managing-Windows-Vista-Group-Policy-Part1.html
http://windowsecurity.com/articles/Managing-Windows-Vista-Group-Policy-Part2.html
http://windowsecurity.com/articles/Managing-Windows-Vista-Group-Policy-Part3.html
All feedback is very welcome - just send me an email!
Written by Jakob H. Heidelberg on November 20th, 2007 with comments disabled.
Read more articles on article and group policy and windowsecurity.com.
Days after a researcher predicted a coming upswing in IT shops' Windows Vista adoption, a second survey draws markedly different conclusions.
Written by WinPlanet Windows Software News on November 20th, 2007 with comments disabled.
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