星空女人频道: 2013-08-18

2013年8月24日星期六

Sea ice decline spurs the greening of the Arctic

Uma Bhatt, an associate professor with UAF's Geophysical Institute, and Skip Walker, a professor at UAF's Institute of Arctic Biology, contributed to a recent review of research on the response of plants, marine life and animals to declining sea ice in the Arctic.

"Our thought was to see if sea ice decline contributed to greening of the tundra along the coastal areas," Bhatt said. "It's a relatively new idea."

The review appeared in a recent issue of Science magazine. It is a close, comprehensive look at how the losses of northern sea ice affect surrounding areas. Bhatt and Walker were two of ten authors.

The review team analyzed 10 years worth of data and research on the subject. The findings show that sea ice loss is changing marine and terrestrial food chains. Sea-ice disappearance means a loss of sea-ice algae, the underpinning of the marine food web. Larger plankton is thriving, replacing smaller, but more nutrient dense plankton. What that means exactly is not yet understood.

Above water, loss of sea ice has destroyed old pathways of animal migration across sea ice while opening new pathways for marine animals in others. Some animals and plants will become more isolated. In the case of the farthest north and coldest parts of the Arctic, entire biomes may be lost without the cooling effects of disappearing summer sea ice.

Walker, a plant biologist, says warming soils provide an opportunity for new vegetation to grow where less vegetation occurred previously. This contributes to a general greening of the Arctic that is visible from space. Bhatt, an atmospheric scientist, examined a 1982-2010 time series of remote sensing data to examine trends in sea ice, land-surface temperatures and changes in the vegetation abundance.

A surprise and puzzling finding shows that despite a general warming and greening of Arctic lands in North America, some areas in northern Russia and along the Bering Sea coast of Alaska are showing recent cooling trends and declines in vegetation productivity.

"We don't know why," Bhatt said.

This all illustrates the complexity of the arctic system and why scientists from different disciplines should work together to understand it, Bhatt said. The review article is one of the first steps in this direction.

"It's not a simple story here," Bhatt said. "I'm an atmospheric scientist and Skip (Walker) is a plant biologist. We have had many conversations to understand each other so we might better understand what's happening in the Arctic."

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.

SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc

we are focus on the following fields,and hope we can help you.

chip Filter saws MURATA IC SANYO IC NEC Diodes Military IC Metal Can Packages Transistors MOTOROLA IC Chip Inductors Electronic News LED part PANASONIC Fleld Effect Transistors NS IC Diodes Renesas parts IC Digital Transistors Cypress IC High Precision Resistors Ligitek LED Resistors INTERSIL IC ELPIDA IC Chip Fuses Industrial IC components TI IC TOSHIBA Diodes BB IC Other Parts Chip Ferrite Beads LINEAR IC ST Diodes Zener Diodes HARRIS IC NEC Transistors Resistor Arrays Multi-units Transistors ROHM Resistors Diodes Inc Connectors
http://www.suvsystem.com/a/5218.aspx

2013年8月23日星期五

LED Lighting Vishay focusses LEDs on gesture recognition

2013/08/23

04sep13VishayIR 390 Vishay has developed high-speed high-power IR LEDs for gesture remote control.

The 940nm devices emit 40mW/sr of radiant power with 100mA drive over +/-18° vertical and +/-36° horizontal (to half intensity.

“The device’s unique angular distribution makes it ideal for gesture remote control of televisions and gaming systems, where it provides excellent spectral matching with silicon photodetectors,” said the firm. “The IR emitter’s wider angle in the horizontal view helps maintain position flexibility for users, while the narrower angle in the vertical plane focuses the distributed radiant intensity.”

Called VSLB9530S, they use GaAIAs multi-quantum well (MQW) technology and come in a 7.62×7.62×4.6mm package with 200K/W thermal resistance.

“While standard IR emitters typically offer drive currents to 100mA, the thermal resistivity of the VSLB9530S allows continuous drive currents up to 150mA, which pushes the achievable radiant intensity to 60mW/sr,” said Vishay. “The device offers modulation bandwidth of 24MHz, and is suitable for high pulse current operation.”

Switching speeds are down to 15ns, and the forward voltage is 1.31V at 150mA. Operating temperature is -40 to +95°C.

Design is to: CECC 00802 for wave soldering, RoHS Directive 2011/65/EU, and halogen-free per JEDEC JS709A.

Samples and production quantities are available now, with eight weeks lead for large orders.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Transistors Freescale Fairchild Semiconductor Transistors YAGEO Resistors Other Parts TOSHIBA Diodes NEC Transistors Rectifier Diodes ELPIDA IC Cypress IC Switching Diodes Infineon Technologies Transistors AD IC Thin Film Resistors Freescale Semiconductor Capacitor Xilinx IC ON Transistors NXP Transistors Renesas parts IC Fleld Effect Transistors Kingbrigt LED Zener Diodes Voltage Regulators Transistors MURATA IC IR transistor LITTELFUSE Diodes Multi-units Transistors DIODES Transistors Diodes FAIRCHILD diodes Texas Instruments(TI) IC Vishay resistors BB IC ST Diodes TDK IC IR Diodes LED Chip Fuses Switches Fast Recovery Diodes
http://www.suvsystem.com/a/5210.aspx

Business SunEdison to spin-off and IPO wafer business

2013/08/23

SunEdison, the re-named MEMC, is to spin off its silicon wafer production business to concentrate on its business of designing, installing and maintaining solar energy farms.

MEMC was renamed SunEdison in May. In its last reported quarter SunEdison had revenues of $400m of which one third came from silicon wafer sales.

However the company reports that wafer sales are weak while solar farm installation is a business with double digit annual growth.

The plan is to spin off the wafer business and IPO a minority holding in the spun off unit in early 2014 and invest the proceeds in its solar farm business.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

chip Filter saws INTERSIL IC LED part BB IC Other Parts Diodes Ligitek LED Discrete Semiconductor Transistors Current Sensors Resistors HARRIS IC Thin Film Resistors IDT IC SANYO IC Vishay resistors Kingbrigt LED PANASONIC Bipolar Transistors MAXIM IC Electronic News IR Diodes Diodes Inc ON Transistors Metal Can Packages Transistors Freescale Semiconductor Transistors Freescale Dialight LED DIODES Transistors Switches TDK IC High Precision Resistors Industrial IC Chip Fuses INFLNEON Diodes About US ROHM Resistors Military IC Fleld Effect Transistors ST Transistors NXP Diodes TOSHIBA Diodes
http://www.suvsystem.com/a/5209.aspx

Business Order surge expected at TSMC

2013/08/23

A note from Barcap says TSMC may see an unseasonal rise in capacity utilisation in Q4 as Sony and Microsoft launch new games machines and Apple launches new iPhones.

Instead of an expected sub-80% Q4 fab utilisation, the Barcap note says utilisation may be between 85 and 90%.

Currently it’s running at 70-75% and Q4 is seasonally slow.

The report prompted a near 3% rise in TSMC’s share price today on the Taiwan exchange.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Pop! Bursting the bubble on carbonation

Aug. 22, 2013 — New research from the Monell Center reveals that bubbles are not necessary to experience the unique 'bite' of carbonated beverages. Bubbles do, however, enhance carbonation's bite through the light feel of the bubbles picked up by our sense of touch.

Share This:

The refreshing bite of carbonation is an integral part of beverages consumed around the globe. Carbonated beverages are produced when carbon dioxide is dissolved in a liquid, typically under high pressure. This can happen naturally in certain spring waters or in fermented beverages like beer. Carbon dioxide also can be added to beverages through production processes.

In either case, when pressure is reduced by opening a bottle or can of a carbonated beverage, some of the carbon dioxide is released from the solution in the form of bubbles. After a sip, enzymes in the mouth convert the remaining free carbon dioxide into carbonic acid. The acid then activates sensory nerve endings, which signal the mild irritation that we refer to as 'bite.'

In the study, published in the public access journal PLOS ONE, the Monell researchers examined the role that bubbles play in carbonation bite. In the first experiment, they took advantage of the fact that bubbles cannot form when atmospheric pressure is raised above a certain level.

Twelve healthy adults were comfortably seated in a hyperbaric chamber and asked to rate the bite intensity of several concentrations of carbonated water. The ratings were collected once while under normal atmospheric pressure (with bubbles) and a second time at higher pressure (no bubbles), equivalent to diving to a depth of 33 feet in sea water.

There was no difference in the bite reported in the two conditions, even though bubbles are physically unable to form at the higher pressure.

"Because the subjects experienced the same bite when bubbles weren't present, the findings clearly told us that carbonation bite is an acidic chemical sensation rather than a purely physical, tactile one," said study author Bruce Byant, PhD, a sensory biologist at Monell.

Although bubbles aren't necessary for bite, they still could be contributing to the overall sensation of carbonation. Thus, a second experiment was designed to address this possibility.

In this experiment, 11 adults rated the intensity of bite in a laboratory setting. The ratings were made for carbonated water under normal conditions and again when additional air bubbles were added to the liquid.

The researchers were surprised to find that air bubbles enhanced the bite of the carbonated bubbles, presumably by stimulating the sense of touch.

"We thought the touch of the bubbles would suppress the painful aspects of carbonation, much as itching a mosquito bite or rubbing a sore muscle does," said Bryant.

Together, the studies reveal that carbon dioxide bubbles are not directly responsible for the bite of carbonation. However, by stimulating the sense of touch inside the mouth, bubbles do enhance the bite sensation beyond the chemical irritation caused by carbonic acid.

"Pain from some cancers also depends on acid formation in tissue," noted study lead author Paul M. Wise, PhD, a sensory psychologist at Monell. "Because the bite from carbonation can be considered to be a mild type of pain, the fact that pain intensity can be enhanced via the sense of touch may have implications for understanding these types of cancer pain."

Future experiments will continue to explore the interactions between chemical and mechanical stimuli.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

NS IC Cypress IC LITTELFUSE Diodes Diodes Thick Film Resistors Discrete Semiconductor Transistors Chip Inductors PANASONIC Resistors NEC Transistors DIODES Transistors IR Diodes Rectifier Diodes SANYO IC Microchip IC MURATA IC PANASONIC IC(Integrated Circuits) Zener Diodes ELPIDA IC NEC Diodes chip Filter saws TOSHIBA Diodes About US BB IC ALTERA IC Transistors Freescale IR transistor IDT IC Freescale Semiconductor MAXIM IC HARRIS IC AVX Resistors Bipolar Transistors Fairchild Semiconductor Transistors Atmel IC ST Diodes Vishay resistors Xilinx IC TOSHIBA Transistors Military IC
http://www.suvsystem.com/a/5191.aspx

Ytterbium atomic clocks set record for stability

NIST's ultra-stable ytterbium lattice atomic clock. Ytterbium atoms are generated in an oven (large metal cylinder on the left) and sent to a vacuum chamber in the center of the photo to be manipulated and probed by lasers. Laser light is transported to the clock by five fibers (such as the yellow fiber in the lower center of the photo). Credit: Burrus/NIST View hi-resolution image

NIST physicists report in the Aug. 22 issue of Science Express that the ytterbium clocks' tick is more stable than any other atomic clock. Stability can be thought of as how precisely the duration of each tick matches every other tick. The ytterbium clock ticks are stable to within less than two parts in 1 quintillion (1 followed by 18 zeros), roughly 10 times better than the previous best published results for other atomic clocks.

This dramatic breakthrough has the potential for significant impacts not only on timekeeping, but also on a broad range of sensors measuring quantities that have tiny effects on the ticking rate of atomic clocks, including gravity, magnetic fields, and temperature. And it is a major step in the evolution of next-generation atomic clocks under development worldwide, including at NIST and at JILA, the joint research institute operated by NIST and the University of Colorado Boulder.

"The stability of the ytterbium lattice clocks opens the door to a number of exciting practical applications of high-performance timekeeping," NIST physicist and co-author Andrew Ludlow says.

Each of NIST's ytterbium clocks relies on about 10,000 rare-earth atoms cooled to 10 microkelvin (10 millionths of a degree above absolute zero) and trapped in an optical lattice -- a series of pancake-shaped wells made of laser light. Another laser that "ticks" 518 trillion times per second provokes a transition between two energy levels in the atoms. The large number of atoms is key to the clocks' high stability.

The ticks of any atomic clock must be averaged for some period to provide the best results. One key benefit of the very high stability of the ytterbium clocks is that precise results can be achieved very quickly. For example, the current U.S. civilian time standard, the NIST-F1 cesium fountain clock, must be averaged for about 400,000 seconds (about five days) to achieve its best performance. The new ytterbium clocks achieve that same result in about one second of averaging time.

Given this high level of stability the ytterbium clocks can make measurements extremely rapidly -- in real time in many cases -- which could be important in rapidly changing application settings, such as the factory floor and the natural environment.

A key advance enabling the milestone performance of the ytterbium clocks was the recent construction of a second version of the clock to measure and improve the performance of the original, developed since 2003. Along the way, NIST scientists have made several improvements to both clocks, including the development of an ultra-low-noise laser used to excite the atoms, and the discovery of a method to cancel disruptive effects caused by collisions between atoms.

The ytterbium clocks' stability record is different from the performance levels previously publicized for NIST-F1, which is traceable to the international system of units, and NIST experimental optical clocks based on single ions, such as the aluminum quantum logic clock or the mercury ion clock. NIST-F1 and the ion clocks were evaluated based on systematic uncertainty, another important metric for standard atomic clocks. NIST-F1's performance is described in terms of accuracy, which refers to how closely the clock realizes the cesium atom's known frequency, or natural vibration rate. Accuracy is crucial for time measurements that must be traced to a primary standard.

NIST scientists plan to measure the accuracy of the ytterbium clocks in the near future, and the accuracy of other high performance optical atomic clocks is under study at NIST and JILA. The research is funded in part by the Defense Advanced Research Projects Agency and the National Aeronautics and Space Administration (NASA).

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Bacteria make us feel pain ... and suppress our immune response

Aug. 21, 2013 — The pain of invasive skin infections caused by methicillin-resistant Staphylococcus aureus, and possibly other serious, painful infections, appear to be induced by the invading bacteria themselves, and not by the body's immune response as previously thought, report scientists at Boston Children's Hospital. What's more, their research demonstrates that once the pain neurons "sense" the bacteria, they suppress the immune system, potentially helping the bacteria become more virulent.

Share This:

The study, conducted in a mouse model and published online by the journal Nature on August 21, could change the way doctors think about a variety of invasive, painful infections, such as meningitis, necrotizing fasciitis, urinary tract infections, dental caries and intestinal infections.

"If we could block pain in infected tissues and also block what pain neurons do to the immune system, it could help us treat bacterial infections better," says Isaac Chiu, PhD, the study's first author and a neuro-immunologist in the laboratory of Clifford Woolf, PhD, at Boston Children's F.M. Kirby Neurobiology Program.

The study was launched after Chiu and coauthor Christian A. Von Hehn, MD, PhD, were culturing sensory neurons and immune cells together in a dish to see how they interact during an infection. "Surprisingly, the neurons were responding immediately to the bacteria," says Chiu.

That inspired them to move to a live model of skin infection, the first one to their knowledge ever used to study pain, working closely with Balthasar Heesters, a graduate student in the lab of Michael Carroll, PhD, in the Program in Cellular and Molecular Medicine at Boston Children's.

The finding that pain neurons, once activated by bacteria, suppress the immune system was equally unexpected. "I was thinking they would do the opposite," says Chiu.

Why would the activated pain neurons try to weaken the immune response to infection? Chiu hypothesizes that the neurons are trying protect tissues from further damage caused by an inflammatory immune response -- a protective mechanism that bacteria might be exploiting to their advantage.

In the study, Chiu and colleagues examined pain, tissue swelling, immune cell numbers and the number of live bacteria in mice with staphylococcal skin infections. They found that pain levels tracked closely with the number of live bacteria and peaked well before tissue swelling peaked, in keeping with bacteria being the cause of the pain and not a local inflammatory response. The team also documented communication between bacteria, pain neurons and key cells from the immune system.

Bacteria "talk to neurons"

The research showed that S. aureus bacteria secrete two kinds of compounds that communicate with sensory neurons, inducing pain:

N-formyl peptides: Pain neurons carry receptors to detect these peptides, known as FPR1 receptors, the team demonstrated. When mice are unable to make these receptors, they show a reduced pain response.
Pore-forming toxins: These proteins, also secreted by other virulent bacteria, dock on the sensory nerve terminals and create large pores that let ions into the cells -- triggering them to fire off pain messages. A pore-forming toxin known as alpha toxin is known to help S. aureus spread in the skin and lungs.

These findings suggest possible new approaches for blocking pain signaling by blocking the FPR1 receptor, blocking the receptor for alpha-toxin (ADAM10) on sensory neurons or possibly delivering a drug through the pores. These approaches also might prevent the neurons from suppressing the immune response, Chiu says, but this has yet to be proven.

Suppressing the immune system

Further experiments in mice demonstrated two ways in which the activated sensory neurons suppress the immune response at the local infection site, potentially allowing bacteria to proliferate:

Innate immunity: Activated pain-sensing neurons reduce the influx of neutrophils and monocytes, key first responders to infection. In mice, when these neurons were eliminated through genetic techniques, numbers of these immune cells increased. The team further showed that the neurons talk to the immune cells via peptide molecules. One called CGRP, for example, prevented macrophages from producing TNF-alpha, a critical signal that rallies further immune defenses against bacteria.
Draining lymph nodes: Normally, antigens from invading bacteria drain from the infection site to the lymph nodes, where T-cells and B-cells congregate and generate the body's second-wave immune response. The team showed, however, that activated pain-sensing neurons reduce migration of T- and B-cells to the lymph nodes. In infected mice whose pain-sensing neurons were eliminated, the lymph nodes contained more of these cells.

The researchers plan to explore the pain-bacteria-immune system relationship further, and investigate treatments to block the pain caused by virulent bacterial infections, and perhaps to counter the immune suppression.

"We found that major parts of the immune system are not necessary for pain during infection, but that bacteria themselves are the source of much of the pain," summarizes Chiu. "In treating pain during infection, we may need to think about how to block the pathogenic components themselves, and not just the immune/inflammatory pathways. We also found that sensory neurons modulate the immune system after they're activated. This suggests, though we haven't yet been able to prove it, that the ability of virulent bacteria strains to cause pain may give them an advantage, by allowing them to use the neurons to suppress immunity."

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

PANASONIC Other Parts Capacitor Transistors Zener Diodes ALTERA IC ST Diodes ON Transistors Low Ohmic Resistors MAXIM IC Bipolar Transistors NXP Transistors Civil IC Chip Fuses Rectifier Diodes Fairchild Semiconductor Transistors TDK IC TI IC Diodes Inc Fast Recovery Diodes Ligitek LED Connectors AD IC IDT IC FAIRCHILD diodes Freescale Semiconductor HARRIS IC Chip Inductors Thin Film Resistors Resistor Arrays YAGEO Resistors Multi-units Transistors ROHM Resistors Diodes Transistors Freescale chip Filter saws Electronic News LINEAR IC NEC Transistors NEC Diodes
http://www.suvsystem.com/a/5176.aspx

Potential for successful climate predictions: Hindcast experiments capture long-term climate fluctuations

What happened in the years 1976/77 and 1998/99 in the Pacific was so unusual that scientists spoke of abrupt climate changes. They referred to a sudden warming of the tropical Pacific in the mid-1970s and rapid cooling in the late 1990s. Both events turned the world's climate topsy-turvy and are clearly reflected in the average temperature of Earth. Today we know that the cause is the interaction between ocean and atmosphere. Is it possible to successfully predict such climate shifts? This is the question that scientists, under the auspices of the GEOMAR Helmholtz Centre for Ocean Research Kiel, pursued. Using a coupled model of the ocean and the atmosphere, they were able to successfully replicate these events.

"The ocean plays a crucial role in our climate system, especially when it comes to fluctuations over several years or decades," explains Prof. Mojib Latif, co-author of the study. "The chances of correctly predicting such variations are much better than the weather for the next few weeks, because the climate is far less chaotic than the rapidly changing weather conditions," said Latif. This is due to the slow changes in ocean currents which affect climate parameters such as air temperature and precipitation. "The fluctuations of the currents bring order to the weather chaos."

The researchers used a climate model, a so-called coupled ocean-atmosphere model, which they forced with the observed wind data of the last decades. For the abrupt changes during the 1970s and 1990s they calculated predictions which began a few months prior to the beginning of the observed climate shifts. The average of all predictions for both abrupt changes shows good agreement with the observed climate development in the Pacific.

"The winds change the ocean currents which in turn affect the climate. In our study, we were able to identify and realistically reproduce the key processes for the two abrupt climate shifts," says Prof. Latif. "We have taken a major step forward in terms of short-term climate forecasting, especially with regard to the development of global warming. However, we are still miles away from any reliable answers to the question whether the coming winter in Germany will be rather warm or cold." Prof. Latif cautions against too much optimism regarding short-term regional climate predictions: "Since the reliability of those predictions is still at about 50%, you might as well flip a coin."

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

2013年8月22日星期四

General Slim power relay for 277Vac 5A loads designed to save energy

2013/08/22

Blue smooth wave template Panasonic’s ALDP relay is extra slim: 7.0mm wide and 15mm high by 20.3mm long.

Intended for refrigerators, domestic boilers, hot water systems, air conditioning, fan heaters, and microwaves (picutred, above), its 200mW coil will switch loads up to 277Vac and 5A.

Available in commonly-used coil voltages between 5Vdc and 24Vdc, it is intended for use in products destined for almost all national and international markets as it is approved to UL, C-UL and VDE standards.

“Reliability and quality is assured as devices are 100% tested by Panasonic immediately after manufacture,” claimed distributor TTI, which is stocking the relay.

Creepage distance and clearances between contact and coil are a minimum of 6mm, in compliance with IEC65.

Surge withstand voltage between contact and coil is more than 10,000V.

Heat resistance and tracking perfomance is to EN60695 (GWT2-11, GWFI2-12, and GWIT2-13).

Ambient temperature operating range is -40°C to +85°C.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

Thick Film Resistors High Precision Resistors NXP Diodes NEC Transistors FAIRCHILD diodes Other Parts Atmel IC Chip Fuses Renesas parts IC Vishay resistors INFLNEON Diodes VISHAY IC components Chip Ferrite Beads Discrete Semiconductor Transistors TOSHIBA Diodes NS IC Freescale Semiconductor Capacitor NXP Transistors Transistors Freescale Digital Transistors chip Filter saws AD IC Metal Can Packages Transistors Dialight LED ELPIDA IC About US Resistor Arrays Voltage Regulators Transistors Connectors ON Transistors TOSHIBA Transistors Resistors ST Transistors Current Sensors Resistors Electronic News Microchip IC Bipolar Transistors Fairchild Semiconductor Transistors
http://www.suvsystem.com/a/5167.aspx

Analogue and Discretes Cree aims at the military with half kilowatt GaN HEMT

2013/08/22

04sep13CreeHEMTs 400 Cree has released a 500W gallium nitride HEMTs for 1.2-1.4GHz L-Band radar amplifier systems.

Called CGHV14500, it also has a 250W partner, the CGHV14250.

According to the firm, they have “the highest known L-Band efficiency performance at 85°C”.

Applications are foreseen between UHF and 1.8GHz in: tactical air navigation systems (TACAN), identification: friend or foe (IFF) systems, and military telemetry.

The devices are being made on Cree’s 50V 0.4µm GaN-on-SiC foundry and are available in ceramic/metal flange and pill packages – claimed to be smaller than competing GaAs or silicon RF technology.

Inputs are internally pre-matched, and the 500W device has 17dB power gain and 70% typical drain efficiency at 85°C.

The 250W device, said Cree, features 330W typical output power as well as 18dB power gain and 77% typical drain efficiency.

Both have 0.3dB pulsed amplitude droop.

Large-scale models are available at Agilent ADS and AWR Microwave, and Digikey is planning to have stock by September.

There is a CGHV14500 video, in which it is described as a 900MHz-1.5GHz transistor.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

NXP Diodes SANYO IC Fast Recovery Diodes ELPIDA IC Digital Transistors LED part NEC Diodes components Texas Instruments(TI) IC VISHAY IC Zener Diodes TI IC Other Parts PANASONIC Resistors MAXIM IC Discrete Semiconductor Transistors Schottky Diodes INTERSIL IC Microchip IC Metal Can Packages Transistors TOSHIBA Diodes NXP Transistors FAIRCHILD diodes LITTELFUSE Diodes IDT IC Dialight LED ST Transistors TDK IC Freescale Semiconductor Electronic News DIODES Transistors About US Fairchild Semiconductor Transistors YAGEO Resistors IC(Integrated Circuits) Resistor Arrays Bipolar Transistors High Precision Resistors ON Diodes Fleld Effect Transistors
http://www.suvsystem.com/a/5163.aspx

Rising mountains, cooling oceans prompted spread of invasive species 450 million years ago

The study, published recently in the journal PLOS ONE, took a closer look at a dramatic ecological shift captured in the fossil record during the Ordovician period. Ohio University scientists argue that major geological developments triggered evolutionary changes in the ancient seas, which were dominated by organisms such as brachiopods, corals, trilobites and crinoids.

During this period, North America was part of an ancient continent called Laurentia that sat near the equator and had a tropical climate. Shifting of Earth's tectonic plates gave rise to the Taconic Mountains, which were forerunners of the Appalachian Mountains. The geological shift left a depression behind the mountain range, flooding the area with cool water from the surrounding deep ocean.

Scientists knew that there was a massive influx of invasive species into this ocean basin during this time period, but didn't know where the invaders came from or how they got a foothold in the ecosystem, said Alycia Stigall, an Ohio University associate professor of geological sciences who co-authored the paper with former Ohio University graduate student David Wright, now a doctoral student at Ohio State University.

"The rocks of this time record a major oceanographic shift, pulse of mountain building and a change in evolutionary dynamics coincident with each other," Stigall said. "We are interested in examining the interactions between these factors."

Using the fossils of 53 species of brachiopods that dominated the Laurentian ecosystem, Stigall and Wright created several phylogenies, or trees of reconstructed evolutionary relationships, to examine how individual speciation events occurred.

The invaders that proliferated during this time period were species within the groups of animals that inhabited Laurentia, Stigall explained. Within the brachiopods, corals and cephalopods, for example, some species are invasive and some are not.

As the geological changes slowly played out over the course of a million years, two patterns of survival emerged, the scientists report.

During the early stage of mountain building and ocean cooling, the native organisms became geographically divided, slowly evolving into different species suited for these niche habitats. This process, called vicariance, is the typical method by which new species originate on Earth, Stigall said.

As the geological changes progressed, however, species from other regions of the continent began to directly invade habitats, a process called dispersal. Although biodiversity may initially increase, this process decreases biodiversity in the long term, Stigall explained, because it allows a few aggressive species to populate many sites quickly, dominating those ecosystems.

This is the second time that Stigall and her team have found this pattern of speciation in the geological record. A study published in 2010 on the invasive species that prompted a mass extinction during the Devonian period about 375 million years ago also discovered a shift from vicariance to dispersal that contributed to a decline in biodiversity, Stigall noted.

It's a pattern that's happening during our modern biodiversity crisis as well, she said.

"Only one out of 10 invaders truly become invasive species. Understanding the process can help determine where to put conservation resources," she said.

Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

we are focus on the following fields,and hope we can help you.

chip Filter saws Texas Instruments(TI) IC Thick Film Resistors Capacitor Ligitek LED Freescale Semiconductor Cypress IC DIODES Transistors Current Sensors Resistors NEC Transistors Fleld Effect Transistors INFLNEON Diodes Electronic News Microchip IC ST Transistors ALTERA IC Low Ohmic Resistors TDK IC Kingbrigt LED TOSHIBA Diodes Xilinx IC Connectors IC(Integrated Circuits) Voltage Regulators Transistors Military IC NS IC components ELPIDA IC Multi-units Transistors IDT IC Zener Diodes IR transistor PANASONIC Resistors AD IC INTERSIL IC Bipolar Transistors Renesas parts IC IR Diodes Other Parts Transistors Freescale
http://www.suvsystem.com/a/5150.aspx

订阅：博文 (Atom)