SCIENCE AND TECHNOLOGY

Plutonium (Worlds Most Dangerous Element )

2011-02-09T00:37:00.000-08:00

Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-white appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen and silicon. When exposed to moist air, it forms oxides and hydrides that expand the sample up to 70% in volume, which in turn flake off as a powder that can spontaneously ignite. It is also a radioactive poison that accumulates in bone marrow. These and other properties make the handling of plutonium dangerous.

Plutonium is the heaviest primordial element, by virtue of its most stable isotope, plutonium-244, whose half-life of about 80 million years is just long enough for the element to be found in trace quantities in nature.

The most important isotope of plutonium is plutonium-239, with a half-life of 24,100 years. Plutonium-239 is the isotope most useful for nuclear weapons. Plutonium-239 and 241 are fissile, meaning the nuclei of their atoms can break apart by being bombarded by slow moving thermal neutrons, releasing energy, gamma radiation and more neutrons. These can therefore sustain a nuclear chain reaction, leading to applications in nuclear weapons and nuclear reactors.

Plutonium-238 has a half-life of 88 years and emits alpha particles. It is a heat source in radioisotope thermoelectric generators, which are used to power some spacecraft.

Plutonium-240 has a high rate of spontaneous fission, raising the neutron flux of any sample it is in. The presence of plutonium-240 limits a sample's usability for weapons or reactor fuel, and determines its grade.

General properties

Name, symbol, number plutonium, Pu, 94

Element category actinide

Group, period, block n/a, 7, f

Standard atomic weight (244)g·mol−1

Electron configuration [Rn] 5f6 7s2

Electrons per shell 2, 8, 18, 32, 24, 8, 2 (Image)

Physical properties

Phase solid

Density (near r.t.) 19.816 g·cm−3

Liquid density at m.p. 16.63 g·cm−3

Melting point 912.5 K, 639.4 °C, 1182.9 °F

Boiling point 3505 K, 3228 °C, 5842 °F

Heat of fusion 2.82 kJ·mol−1

Heat of vaporization 333.5 kJ·mol−1

Specific heat capacity (25 °C)

35.5 J·mol−1·K−1

Bacteria

2011-02-05T21:11:00.000-08:00

Bacteria are a large group of single-celled, prokaryote microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals. Bacteria are ubiquitous in every habitat on Earth, growing in soil, acidic hot springs, radioactive waste, water, and deep in the Earth's crust, as well as in organic matter and the live bodies of plants and animals. There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water; in all, there are approximately five nonillion (5×1030) bacteria on Earth, forming much of the world's biomass.Bacteria are vital in recycling nutrients, with many steps in nutrient cycles depending on these organisms, such as the fixation of nitrogen from the atmosphere and putrefaction. However, most bacteria have not been characterised, and only about half of the phyla of bacteria have species that can be grown in the laboratory.The study of bacteria is known as bacteriology, a branch of microbiology.

There are approximately ten times as many bacterial cells in the human flora as there are human cells in the body, with large numbers of bacteria on the skin and as gut flora.The vast majority of the bacteria in the body are rendered harmless by the protective effects of the immune system, and a few are beneficial. However, a few species of bacteria are pathogenic and cause infectious diseases, including cholera, syphilis, anthrax, leprosy and bubonic plague. The most common fatal bacterial diseases are respiratory infections, with tuberculosis alone killing about 2 million people a year, mostly in sub-Saharan Africa. In developed countries, antibiotics are used to treat bacterial infections and in agriculture, so antibiotic resistance is becoming common. In industry, bacteria are important in sewage treatment, the production of cheese and yogurt through fermentation, as well as in biotechnology, and the manufacture of antibiotics and other chemicals.

Motorola Xoom

2011-02-04T09:50:00.000-08:00

Features

Android 3.0
10.1 inch display
Dual Core 1 Ghz CPU NVIDIA Tegra 2
1GB RAM
32 GB inbuilt memory with microSD Card slot
10 hr video playback battery life
5 MP Rear camera with Flash and 720p HD video capture
2MP video calling camera
Wifi(n) Bluetooth 2.1, 3G , 4G

Motorola XOOM Tablet

OS Android 3.0 Honeycomb

Differentiation Larger display in smaller form-factor, 1080p HD support, first tablet with Honeycomb software, dual-core 1GHz processor, and a wide range of docking options

Dimensions 249.1mm (h) x 167.8mm (w) x 12.9mm (d)

Display 10.1” 1280×800 resolution

Weight 730 g

Processor NVIDIA® Tegra™ 2: 1GHz dual-core processor

Battery Up to 10 hour video playback

Connectivity 3.5mm, micro USB 2.0 HS, Corporate Sync, Wi-Fi 2.4GHz & 5GHz 802.11b/g/n, Bluetooth 2.1 + EDR + HID

Network 3 G, 4G LTE upgradeable, 802.11n w/Personal Hotspot

Messaging/Web/Apps Email (Corporate Sync, Google Mail, POP3/IMAP embedded, Push Email, Yahoo Mail) , WebKit w/ Flash

Audio AAC, AAC+, AMR NB, AMR WB, MP3, XMF

Video 720p capture/1080p playback/streaming, H.263, H.264, MPEG4

Camera 5 MP rear-facing camera with dual LED flash/2MP front-facing camera

Memory 32GB on board user memory, SD card support after software update, 1GB DDR2 RAM

Nanotechnology

2011-02-03T19:03:00.000-08:00

vanadium(IV) oxide

Nanotechnology (sometimes shortened to "nanotech") is the study of manipulating matter on an atomic and molecular scale. Generally, nanotechnology deals with structures sized between 1 to 100 nanometer in at least one dimension, and involves developing materials or devices within that size. Quantum mechanical effects are very important at this scale, which is in the quantum realm.
Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale.

There is much debate on the future implications of nanotechnology. Nanotechnology may be able to create many new materials and devices with a vast range of applications, such as in medicine, electronics, biomaterials and energy production. On the other hand, nanotechnology raises many of the same issues as any new technology, including concerns about the toxicity and environmental impact of nanomaterials, and their potential effects on global economics, as well as speculation about various doomsday scenarios. These concerns have led to a debate among advocacy groups and governments on whether special regulation of nanotechnology is warranted.
Nanoparticle
In nanotechnology, a particle is defined as a small object that behaves as a whole unit in terms of its transport and properties. Particles are further classified according to size: in terms of diameter, fine particles cover a range between 100 and 2500 nanometers. On the other hand, ultrafine particles are sized between 1 and 100 nanometers. Similar to ultrafine particles, nanoparticles are sized between 1 and 100 nanometers. Nanoparticles may or may not exhibit size-related properties that differ significantly from those observed in fine particles or bulk materials.Although the size of most molecules would fit into the above outline, individual molecules are usually not referred to as nanoparticles.

(a, b, and c) images of prepared mesoporous silica nanoparticles with mean outer diameter: (a) 20nm, (b) 45nm, and (c) 80nm. SEM (d) image corresponding to (b). The insets are a high magnification of mesoporous silica particle.

World's smallest flower (Wolffia)

2011-01-30T18:32:00.000-08:00

Wolffia is a genus of 9 to 11 species which include the smallest flowering plants on Earth. Commonly called water-meal, these aquatic plants resemble specks of cornmeal floating on the water. Wolffia species are free-floating thalli, green or yellow-green, and without roots. The flower is produced in a depression on the top surface of the plant body. It has one stamen and one pistil. Individuals often float together in pairs or form floating mats with related plants, such as Lemna and Spirodela species. Most species have a very wide distribution across several continents. Wolffia species are composed of about 40% protein, about the same as the soybean, making them a potential high-protein human food source. They have historically been collected from the water and eaten as a vegetable in much of Asia.

Sony Ericsson Xperia x10

2011-01-30T16:47:00.000-08:00

Xperia x10

Screen
- 480 x 854 pixels (WVGA)
- 4" capacitive touchscreen
Memory
- Phone memory up to 1GB
- microSD™ up to 16GB, 8GB included
* Actual free memory may vary due to phone pre-configuration.

Networks
- GSM/GPRS/EDGE 850/900/1800/1900
- UMTS/HSPA 900/1700/2100
- UMTS/HSPA 800/850/1900/2100
Available colours
- Sensuous Black - Luster White
Possible limited market availability.

Sizes
- 119.0 x 63.0 x 13.0 mm
- 4.7 x 2.5 x 0.5 inches
Weight
- 135.0 gr
- 4.8 oz

Ultimate Portable Entertainment (PSP) NGP

2011-01-29T21:55:00.000-08:00

PlayStationPortable
On 27 January 2011 at a specially convened press conference in Tokyo, Japan, Sony Computer Entertainment Inc. (SCE) announced its next generation portable entertainment system (code name: NGP), which delivers the ultimate portable entertainment experience.

NGP will arrive at the end of 2011 and is designed to offer unparalleled interactive entertainment that only PlayStation can deliver. This new system offers a revolutionary combination of rich gaming and social connectivity within a real world context, made possible by maximising SCE's experience from both PSP and PlayStation 3.

Deep and immersive gaming is at the core of the PlayStation DNA, and NGP is the latest embodiment of this vision. By having both Wireless and 3G network connectivity, together with various applications, NGP will enable infinite possibilities for users to connect, share and play with friends wherever they are.

The device includes a range of features that provide a genuinely cutting-edge, next generation, ultimate portable entertainment experience, such as:

Technical Specs:

CPU

ARM® Cortex™-A9 core (4 core)
GPU

SGX543MP4+
External Dimensions

Approx. 182.0 x 18.6 x 83.5mm (width x height x depth) (tentative, excludes largest projection)
Screen
(Touch screen) 5 inches (16:9), 960 x 544, Approx. 16 million colors, OLED
Multi touch screen (capacitive type)
Rear touch pad

Multi touch pad (capacitive type)
Cameras

Front camera, Rear camera
Sound

Built-in stereo speakers
Built-in microphone
Sensors

Six-axis motion sensing system (three-axis gyroscope, three-axis accelerometer), Three-axis electronic compass
Location

Built-in GPS
Wi-Fi location service support
Keys / Switches

PS button
Power button
Directional buttons (Up/Down/Right/Left)
Action buttons (Triangle, Circle, Cross, Square)
Shoulder buttons (Right/Left)
Right stick, Left stick
START button, SELECT button
Volume buttons (+/-)
Wireless communications Mobile network connectivity (3G)
IEEE 802.11b/g/n (n = 1×1) (Wi-Fi) (Infrastructure mode/Ad-hoc mode)
Bluetooth® 2.1+EDR （A2DP/AVRCP/HSP）