New Si based photovoltaic cells may be the light of the future

first_imgThe problem of forming an uniform polysilane film was solved by carefully examining controlled parameters and optimizing the burning conditions of the polysilane film and reduced the density of the unattached hands to 1 x 1016/cm3. More details of the development process were not made public. The pin-type amorphous Si PV cells were put on the glass substrate by using a new coating process, which allowed the p- and n-layers to be formed by using the chemical vapor deposition method. The conversion efficiency of the cell that has their p-, i- and n-layers formed by using this coating process was 0.51%. This is tempered by the fact that the thickness of the new cell’s i-layer is 120nm. This makes them significantly thinner than the amounts found in existing amorphous Si PV cells, which have a thickness of 250nm.Researchers at JAIST believe that if this thickness is increased the efficiency will improve. Citation: New Si based photovoltaic cells may be the light of the future (2011, February 10) retrieved 18 August 2019 from https://phys.org/news/2011-02-si-based-photovoltaic-cells-future.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Sharp Develops Mass-Production Technology for Triple-Junction Thin-Film Solar Cells (PhysOrg.com) — A team of scientists at the Japan Advanced Institute of Science and Technology, or JAIST for short, led by Tatsuya Shimoda, a professor at the JAIST School of Materials Science, has created an amorphous silicon photovoltaic cell by applying a liquid Si. This world’s first inphotovoltaics has a conversion efficiency of 1.79% which, when applied to a pin-type cell whose i-layer was made with the coating process, according to JAIST researchers. They also have hopes that when the efficiency of the amorphous silicon photovoltaic cells improves in the future, it may become possible to mass-produce the Si PV cells by using a roll-to-roll method.The research group started with cyclopentasilane, a liquid Si, but they did not reveal any further specifics of the liquid Si. We do know that it was developed by emitting ultraviolet rays at CPS in a carbon hydrogen solvent in order to polymerize part of the CPS to make a polysilane. This Liquid Si was developed during the period between 2006 and 2007. © 2010 PhysOrg.com More information: Information in Japanese: translate.google.com/translate … news/2011/02/10/011/ Explore furtherlast_img read more

Chameleons ballistic tongue inspires robotic manipulators

first_img Why chameleon tongues work in the cold (w/ Video) Explore further When fully extended, a chameleon’s tongue can reach twice the chameleon’s body length. Image credit: G. A. Boulenger. Wikimedia Commons. Copyright 2010 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. More information: Alexis Debray. “Manipulators inspired by the tongue of the chameleon.” Bioinsp. Biomim. 6 (2011) 026002 (15pp). DOI:10.1088/1748-3182/6/2/026002 With the aim to mimic the mechanisms and performance of the chameleon’s tongue, researcher Alexis Debray of Canon, Inc., in Tokyo, Japan, has developed four ballistic robotic manipulators. Each of the four manipulators excels at copying a certain part of the chameleon’s tongue, and insights from each design could eventually be combined to create a more advanced chameleon tongue that could have manufacturing applications. Debray’s study is published in a recent issue of Bioinspiration & Biomimetics.“As far as I know, this is the first published demonstration of manipulators based on the chameleon tongue,” Debray told PhysOrg.com. “The particular mechanism of the tongue of the chameleon allows for fast accelerations and velocities and also applies no force during most of the motion.”As Debray explains, what we normally think of as the tongue of the chameleon is actually a larger system called the hyolingual apparatus. The tongue is just a small component on the front tip of the hyolingual apparatus. The majority of the hyolingual apparatus consists of the long, thin hyoglossus complex, which is the part that folds up like an accordion inside the chameleon’s mouth. The rapid movement of the chameleon’s hyolingual apparatus involves three phases: projection, catching, and retraction. Each of these three phases is controlled by a different system. The tongue (tip of the hyolingual apparatus) contains the accelerator muscle and collagens that control the projection. When the chameleon is ready to project, it slowly protrudes its tongue out of its mouth. Then, the tongue’s accelerator muscle projects the tongue off a bone inside the chameleon’s mouth. No applied force is needed to keep the tongue – and the rest of the hyolingual apparatus – moving forward. When the tongue reaches its prey, a tongue pad containing a small suction on the tip of the tongue can stick to the prey. Finally, the hyoglossus muscle in the accordion-like hyoglossus complex retracts the tongue at a constant velocity. Although the three phases are controlled by different systems, they occur in a single smooth, continuous motion.center_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Like the chameleon tongue, Debray’s robotic manipulators use different specialized systems for projection, catching, and retraction. To project, all four manipulators use a coilgun in place of the chameleon tongue’s accelerator muscle. Elastomers and/or cotton string is used in place of the chameleon’s hyolingual apparatus. Instead of folding up like an accordion, the elastomers and string are wound around a reel. As for catching, the robotic manipulators use magnets on the tip of the elastomers, which attract magnetic “prey.” For retraction, the manipulators use either an elastomer, a DC motor connected to a reel and string, or a combination of both. One of the manipulators also had wings on the mobile part, which could allow researchers to take advantage of aerodynamic effects.“In the future, movable wings will allow controlling the trajectory after the ejection of the tongue, which is not possible now,” Debray said. “In our experiments, the wings are not movable. However, their aerodynamic effect on the trajectory of the tongue has been demonstrated experimentally. So far, aerodynamic effects have been poorly studied in the field of manipulators.”Using a high-speed camera, Debray could track the manipulators in motion. The results showed that the robotic manipulators could reach a projection velocity of 3.8 meters/second without the need for a continuously applied force, which is similar to the velocity of the chameleon tongue. In addition, the robotic manipulators could reach an acceleration of 919 meters/second2, which exceeds that of the chameleon (374 meters/second2). The manipulators that used a DC motor and string for retraction had the same extension ability as the chameleon tongue, and could also adapt to variations in the targets’ distances, as chameleons can. By incorporating various end effectors onto the robotic manipulators, the devices could have a variety of applications, especially for products passing on a factory line. For example, manipulators with sensors could be used to sense data on products. Stamps and catching devices could be used to deposit patterns and manipulate objects, respectively. Using a mechanism based on the chameleon’s ballistic tongue could provide certain advantages compared with other manipulators due to the small size and flexibility. Further, because ballistic manipulators do not apply a continuous force during their forward motion, an accidental collision would be less severe and likely cause less damage compared to a device being pushed forward. As Debray explained, the current manipulators lack reliability, and so they cannot yet be put to practical use.“The work presented in the paper is a first step towards manipulators inspired by the chameleon tongue,” Debray said. “Further development is needed in order to use them in factory lines. However, the ultimate goal of this work is the manufacture of Canon products such as cameras and printers, among others.” (PhysOrg.com) — Although the lungless salamander and some frog species have developed ballistic tongues, the chameleon’s ballistic tongue is the fastest, the longest, and the one that can catch the heaviest prey. A chameleon’s tongue can elongate more than six times its rest length, zipping forward at speeds of 3.5-10.5 meters/second – faster than a human eye can follow. The tongue is called ballistic because, like all ballistic objects, it moves freely without any applied force during its forward motion. Once the chameleon’s accordion-like tongue is ejected, it continues moving forward under its own inertia. Citation: Chameleon’s ballistic tongue inspires robotic manipulators (2011, April 5) retrieved 18 August 2019 from https://phys.org/news/2011-04-chameleon-ballistic-tongue-robotic.htmllast_img read more

Apparent roadblock in the development of quantum lithography

first_img © 2010 PhysOrg.com (PhysOrg.com) — Just when it began to appear that scientists had found a viable way around the problem of the blurring that occurs when using masks to create smaller and smaller silicon wafers for computer chips, a previous study on beam splitting optics showed that the new approach would not work, at least as it has thus far been proposed. A group of researchers explain why in a paper in New Journal of Physics. Quantum electronics: Two photons and chips Currently, the silicon wafers that make up computer chips are made by the process of lithography, whereby optics are used to create an image on a piece of wafer. To create the channels that make up the transistors, masks are used to prevent some of the photons directed towards a wafer from arriving. When the wafer is then immersed in special chemicals, the parts that were struck react differently than those that weren’t, creating the channels. The problem is in the clarity of the image produced on the other side due to the use of optic lenses to focus the photons, as some degree of blurring will always occur due to the nature of lenses. As researchers try to make smaller transistors, the blurring eventually becomes a roadblock, which is why some are looking for alternatives.One such approach is to take advantage of the unique properties of entangled photons; those wily quantum particles that for some inexplicable reason, tend to mimic the behavior of one another, without any apparent means of communication, and at a rate faster than the speed of light. Because they are correlated, the thinking went, they’d always arrive at the same place at the same time (in this case a sensor) creating a near perfect image; so if say a mask were made, in this case a simple one with just two slits in it; it would make sense that the pair of entangled photons would interfere with one another as they tend to do, as they pass through the slit, then arrive together on the other side at exactly the same place and time, which is just what you’d need if you wanted to impact the material on the other side to create your wafer the way you intended. Unfortunately, things haven’t worked out quite that way, because as it turns out, while you can expect a pair of entangled photons to do their thing simultaneously, you can’t rely on them to arrive at the same target, or again in this case, the same sensor, while they are doing so; which of course is a big problem if you’re trying to make a wafer where the photons have to hit their target not only at exactly the same time, but in exactly the right place or you’ve got nothing to show for your efforts.Even so, researchers hoped that enough photons would arrive in the same place at the same time by chance to allow for the process to work; but this meant adding in an exposure time (waiting for enough of the photons to arrive at the same place) which as it turned out rose too rapidly as the feature size requirements went up, making the process unfeasible.While it appears the original idea for using entangled photons for the development of quantum lithography won’t work, researchers aren’t giving up hope just yet; the stakes are too high. The hope now is that some other new imaginative way can be thought of to get around the problems encountered, allowing for the creation of almost unimaginably small chips. Citation: Apparent roadblock in the development of quantum lithography (2011, May 20) retrieved 18 August 2019 from https://phys.org/news/2011-05-apparent-roadblock-quantum-lithography.html More information: On the efficiency of quantum lithography, Christian Kothe et al 2011 New J. Phys. 13 043028 doi:10.1088/1367-2630/13/4/043028AbstractQuantum lithography promises, in principle, unlimited feature resolution, independent of wavelength. However, in the literature, at least two different theoretical descriptions of quantum lithography exist. They differ in the extent to which they predict that the photons retain spatial correlation from generation to absorption, and although both predict the same feature size, they vastly differ in predicting how efficiently a quantum lithographic pattern can be exposed. Until recently, essentially all quantum lithography experiments have been performed in such a way that it is difficult to distinguish between the two theoretical explanations. However, last year an experiment was performed that gives different outcomes for the two theories. We comment on the experiment and show that the model that fits the data unfortunately indicates that the trade-off between resolution and efficiency in quantum lithography is very unfavourable. Explore further When sending two photons through a double slit they will produce an interference pattern on a detection line after the slits. Denoting the arrival position of the photons with s and t one can plot the detection probability where lighter colour indicates higher probability. If the photons are constrained to arrive at the same place the left figure applies; if they propagate independently the right figure applies. Image credit: New J. Phys. 13 043028 doi:10.1088/1367-2630/13/4/043028 This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Safer way to make diazomethane developed

first_img Diazomethane (CH2N2) is a toxic yellow gas at 25 degrees Celsius, and is usually used in solution in ether. It is a useful reagent for many reasons, such as its ability to be converted to carbene, which is used in the synthesis of cyclopropanes. It is usually prepared as needed in the lab by hydrolysis of a precursor such as diazald (N-methyl-N-nitroso-p-toluenesufonamide), but becomes explosive during the processes of purifying and isolating it. Safety precautions such as preparing the chemical in a fume hood or behind a blast shield, avoiding ground glass joints, wearing thick protective gloves, avoiding any sharp edges or scratches on the glassware, and so on, are employed during the synthesis to protect the scientists from potential explosions.Researchers Erick Carreira and Bill Morandi of the Laboratory of Organic Chemistry at ETH in Zurich have developed a new method for generating diazomethane in situ that uses a catalyst and avoids the need for the dangerous isolation process and generation of large volumes of the explosive chemical. The catalyst is an iron porphyrin complex and is used to catalyze the cyclopropanation of olefins such as styrenes, dienes, and enynes in an aqueous solution of potassium hydroxide (6M, KOH). Since olefins are immiscible with water, they create a safe biphasic environment for the formation of the intermediate, diazomethane, which is constantly generated and immediately consumed in the reaction. The catalyst remains within the olefin phase.The new method is safer for the chemists because there is a much lower risk of explosion since the diazomethane is consumed as soon as it is created, and large volumes do not accumulate. There is also a much lower chance of exposure to the toxic gas.In the paper, published in Science, Carreira and Morandi suggest the method could also be used in the synthesis of other toxic or explosive reagents, provided they can be prepared in aqueous solutions. More information: Iron-Catalyzed Cyclopropanation in 6 M KOH with in Situ Generation of Diazomethane, Science 23 March 2012: Vol. 335 no. 6075 pp. 1471-1474, DOI: 10.1126/science.1218781ABSTRACTDiazomethane is a common and versatile reagent in organic synthesis whose broader use is generally impeded by its explosiveness and toxicity. Here we report that a simple iron porphyrin complex catalyzes the cyclopropanation of styrenes, enynes, and dienes under the demanding conditions [aqueous 6 molar potassium hydroxide (KOH) solution, open to air] necessary for the in situ generation of diazomethane from a water-soluble diazald derivative. A biphasic reaction medium arising from the immiscibility of the olefin substrates with water appears essential to the overall efficiency of the process. The work we describe highlights an approach to catalysis with untoward reactive intermediates, in which the conditions for their generation under operationally safe regimes dictate catalyst selection. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. (PhysOrg.com) — Diazomethane is a toxic, explosive reagent prepared as needed in laboratories, where it is commonly used in cyclopropanation, but its explosive nature prevents it being used widely on an industrial scale. Now, scientists in Switzerland have developed a new method of synthesising diazomethane that is much safer and therefore could lead to much wider use. Journal information: Science Microscale Chemical Factory © 2011 PhysOrg.com Explore further Citation: Safer way to make diazomethane developed (2012, March 23) retrieved 18 August 2019 from https://phys.org/news/2012-03-safer-diazomethane.htmllast_img read more

Time found to be fixed to terrain for Papua New Guinea tribe

first_imgIn interviewing many of the people that live in Gua, the researchers found that when asked questions about the past or the future, their responses were almost always relative to their position along the river. The past was downriver, the future was upriver, regardless of which direction the river happened to be flowing.Interestingly, the perspective of time changed for the villagers when inside their homes. There the past was represented by the doorway, and the future away from the door, which might seem counterintuitive until noting that for those that live in Gua, the doorway is always seen as downhill which is likely to promote drainage after rains; both water and time, flowing away when viewed from the vantage point of those sitting safely inside their homes. The Yupno people live in a village called Gua. There are no roads leading in or out and the only other people the villagers see are the occasional missionaries, researchers or governmental health workers. Thus, their way of life hasn’t changed much, as most of the rest of the world marched into what we now perceive as a very modern society. And because of that, the Yupno people have retained their own interpretation of time, and for them, it’s all about the river. And because of that, time for them can be construed as running straight, as it does for us westerners, but only where the river runs straight. Where it kinks, so too does time. Future is uphill; past is downhill. Image (c) [i]Cognition[/i], DOI:10.1016/j.cognition.2012.03.007 © 2012 Phys.Org Journal information: Cognition This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. More information: Contours of time: Topographic construals of past, present, and future in the Yupno valley of Papua New Guinea, Cognition, dx.doi.org/10.1016/j.cognition.2012.03.007AbstractTime, an everyday yet fundamentally abstract domain, is conceptualized in terms of space throughout the world’s cultures. Linguists and psychologists have presented evidence of a widespread pattern in which deictic time—past, present, and future—is construed along the front/back axis, a construal that is linear and ego-based. To investigate the universality of this pattern, we studied the construal of deictic time among the Yupno, an indigenous group from the mountains of Papua New Guinea, whose language makes extensive use of allocentric topographic (uphill/downhill) terms for describing spatial relations. We measured the pointing direction of Yupno speakers’ gestures—produced naturally and without prompting—as they explained common expressions related to the past, present, and future. Results show that the Yupno spontaneously construe deictic time spatially in terms of allocentric topography: the past is construed as downhill, the present as co-located with the speaker, and the future as uphill. Moreover, the Yupno construal is not linear, but exhibits a particular geometry that appears to reflect the local terrain. The findings shed light on how, our universal human embodiment notwithstanding, linguistic, cultural, and environmental pressures come to shape abstract concepts. Citation: Time found to be fixed to terrain for Papua New Guinea tribe (2012, June 4) retrieved 18 August 2019 from https://phys.org/news/2012-06-terrain-papua-guinea-tribe.html (Phys.org) — For most of western history, people have assumed that what is true of “us” in most cases, must be true for “them,” i.e. other groups about which we may actually know little. One example is the concept of time. In virtually all western societies, people envision time in the same abstract way; as a line moving from the past, through us, and on into the future. We speak of back in the past, or moving forward into the future. And because our way of thinking about time is so ingrained in us it’s difficult to imagine that others might really see time in radically different ways. And yet, some do, as evidenced by a remote tribe of people currently living in Papua New Guinea. The Yupno, a team of researchers has found, relate time to the river that dominates their life. The past is water that has already flowed by, while the future is represented by its source, which for them, lies uphill. Rafael Núñeza, Kensy Cooperridera, D Doana and Jürg Wassmannb studied the Yupno and found, as they report in their paper published in Cognition, that some people living in circumstances far different than that seen in the western world, really do see time in a completely different way. Explore further Learned, not innate human intuition: Study finds twist to the story of the number linelast_img read more

Astronomers discover first selflensing binary star system

first_img Explore further Scientists believe that nearly half of the stars in the night sky are multi-star systems, many of them binaries. Also, some binary star systems are unique in that their orbital path around each other lies in a plane with the planet Earth, which means from our perspective, they pass in front of one another on a periodic basis, causing an eclipse—generally, this results in dimming, which some might see as twinkling. In other instances, theory has suggested, the opposite should occur—instead of dimming, the eclipse should result in brightening—a phenomenon known as self-lensing—as the star in front magnifies light from the star behind it.Self-lensing is based on Einstein’s theory of relativity—light may not have mass, but it is still subject to gravity, it bends when passing stars for example. For that reasons, astronomers have been suggesting for years that if there existed a binary star system where one of the stars was similar to our own sun, but the other was a white dwarf—small but with a huge mass, and thus lots of gravity—than self-lensing should occur when the smaller star passed in front of the larger star. And that’s just what Kruse and Agol have found. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen Play Simulation of gravitational microlensing in the KOI-3278 system using an image of our Sun as a proxy for the G star companion of the white dwarf. The blue sphere is the white dwarf. The large orange sphere is the G dwarf (using a NASA SDO/HMI false-color image of our Sun, since the star is very similar in properties to our Sun). The simulation shows how the G star is distorted by gravitational lensing by the white dwarf star if it could be seen at high resolution. Credit: Eric Agol (UW), NASA/SDO HMI science teams The two were studying the star KOI 3278 because it had previously been found to dim on a periodic basis. Thinking it was doing so because of a planet passing in front of it, the researchers looked closer. Instead of a planet, the researchers discovered another star. As they orbited, the two stars took turns passing between us and their mate, every 88 days. When the sun-sized star was out front, the binary system dimed, as occurs with most binary star systems. But when the smaller star was out front, the two observed, instead of growing dimmer, the result was a very subtle brightening (a 0.1 percent increase) that lasted for five hours, confirming theories and stoking hopes that one day an observation will be made of a similar system made up of neutron stars or black holes. (Phys.org) —A pair of astronomers at the University of Washington has discovered the first known instance of a self-lensing binary-star system. In their paper published in the journal Science, Ethan Kruse and Eric Agol describe how they happened across the previously theorized system while looking for undiscovered planets. Gravity-bending find leads to Kepler meeting Einsteincenter_img More information: KOI-3278: A Self-Lensing Binary Star System, Science 18 April 2014: Vol. 344 no. 6181 pp. 275-277 DOI: 10.1126/science.1251999ABSTRACTOver 40% of Sun-like stars are bound in binary or multistar systems. Stellar remnants in edge-on binary systems can gravitationally magnify their companions, as predicted 40 years ago. By using data from the Kepler spacecraft, we report the detection of such a “self-lensing” system, in which a 5-hour pulse of 0.1% amplitude occurs every orbital period. The white dwarf stellar remnant and its Sun-like companion orbit one another every 88.18 days, a long period for a white dwarf–eclipsing binary. By modeling the pulse as gravitational magnification (microlensing) along with Kepler’s laws and stellar models, we constrain the mass of the white dwarf to be ~63% of the mass of our Sun. Further study of this system, and any others discovered like it, will help to constrain the physics of white dwarfs and binary star evolution. Citation: Astronomers discover first self-lensing binary star system (2014, April 18) retrieved 18 August 2019 from https://phys.org/news/2014-04-astronomers-self-lensing-binary-star.html © 2014 Phys.org Journal information: Science Geometry and light curve of the KOI-3278 system. As the white dwarf orbits a G dwarf (sun-like star) in this system, when the white dwarf passes in front of the G dwarf, it causes gravitational magnification, resulting in a pulse with a duration of 5 hours and height of 0.1%, while when it passes behind, it is blocked from view, causing an occultation and a dip, also of 0.1% (by coincidence). The black line represents the orbital flux as a function of time, relative to the flux only of the G dwarf (which is shown as a dotted line). This diagram is not to scale, and does not show the stellar variability or noise. For example, the pulse and occultation only last 5 hours out of the 88.2 days of the orbit, while in this diagram they last a much larger fraction of the orbit. Credit: Eric Agollast_img read more

Curiosity finds rocks that might point to a continental crust on Mars

first_img Explore further Geologic study suggests Earth’s tectonic activity peaked 1.1 billion years ago Igneous clast named Harrison embedded in a conglomerate rock in Gale crater, Mars, shows elongated light-toned feldspar crystals. The mosaic merges an image from Mastcam with higher-resolution images from ChemCam’s Remote Micro-Imager. Credit: NASA/JPL-Caltech/LANL/IRAP/U. Nantes/IAS/MSSS. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. The findings do not confirm magmatic activity on the planet or the existence of tectonic plates, the researchers acknowledge, they simply suggest it might have been a possibility. The rock samples could have come to be the way they are, for example, by the partial melting of basalts as they sank back into the crust. As always, more research will be needed to truly understand the history of the rocks. Diversity of rock textures. Credit: Nature Geoscience (2015) doi:10.1038/ngeo2474 More information: In situ evidence for continental crust on early Mars, Nature Geoscience (2015) DOI: 10.1038/ngeo2474AbstractUnderstanding of the geologic evolution of Mars has been greatly improved by recent orbital, in situ and meteorite data, but insights into the earliest period of Martian magmatism (4.1 to 3.7 billion years ago) remain scarce9. The landing site of NASA’s Curiosity rover, Gale crater, which formed 3.61 billion years ago within older terrain, provides a window into this earliest igneous history. Along its traverse, Curiosity has discovered light-toned rocks that contrast with basaltic samples found in younger regions. Here we present geochemical data and images of 22 specimens analysed by Curiosity that demonstrate that these light-toned materials are feldspar-rich magmatic rocks. The rocks belong to two distinct geochemical types: alkaline compositions containing up to 67 wt% SiO2 and 14 wt% total alkalis (Na2O + K2O) with fine-grained to porphyritic textures on the one hand, and coarser-grained textures consistent with quartz diorite and granodiorite on the other hand. Our analysis reveals unexpected magmatic diversity and the widespread presence of silica- and feldspar-rich materials in the vicinity of the landing site at Gale crater. Combined with the identification of feldspar-rich rocks elsewhere and the low average density of the crust in the Martian southern hemisphere, we conclude that silica-rich magmatic rocks may constitute a significant fraction of ancient Martian crust and may be analogous to the earliest continental crust on Earth.Press releasecenter_img (Phys.org)—A team of researchers from the U.S., France and the U.K. is reporting that data sent back by the Mars rover Curiosity suggests that the Red Planet may have once had a continental crust similar to that found back here on planet Earth. In their paper published in the journal Nature Geoscience, the team describes their analysis of data describing 20 rocks that had been probed by the rover, and why their findings suggest a different history for the planet than has been thought. With all the excitement and news coming from the New Horizons probe as it conducts a flyby of Pluto, it is easy to forget that the Mars rover Curiosity is still active and still sending back valuable information. In this latest bit of news, researchers studying data sent back from the probe believe they have found evidence that suggests that rather than a lack of magmatic planetary activity, which should have been evident in rock samples showing mostly basalt, rock samples are full of silica and have a rich composition.The light-colored rock samples are from an area inside the Gale Crater (in the southern hemisphere near Mount Sharp) and have been dated back to approximately 3.6 billion years ago. The researchers describe the rocks as looking like mineral composition samples taken from Earth, a huge departure from the dark basalt that was expected. The similarity suggests the planet may once have experienced plate tectonics similar to that on Earth. Up until now, the assumption has been that Mars did not have magmatic activity, which it is believed would have been necessary for the development of plates. That would have left the surface covered with basalt, similar to the situation at the bottom of our own world’s oceans. The researchers note that for some of the rocks the ingredients are actually very similar to some of the oldest continental materials on Earth. © 2015 Phys.org Citation: Curiosity finds rocks that might point to a continental crust on Mars (2015, July 14) retrieved 18 August 2019 from https://phys.org/news/2015-07-curiosity-continental-crust-mars.html Journal information: Nature Geosciencelast_img read more

CPM BJP Congress hold rally together in Nadia

first_imgKolkata: The allegations made by Trinamool Congress supremo Mamata Banerjee that Congress, CPI-M and BJP are fighting the three tier Panchayat election holding each other’s hands when a rally comprising the members of these parties was taken out in Nadia on Saturday.The rally which was taken out at Gangnapur gram panchayat area in Nadia was led by Rama Biswas, CPI-M MLA and state committee member of the party. She was the former Sabhadhipati of Nadia district. The candidates of all the three parties took part in the rally and urged people to vote for them. It may be mentioned that Mamata Banerjee have made this allegation over and again and criticised CPI-M for failing to stop the flight of its cadres of BJP. Sixty thousand cadres in Bengal have not renewed their membership and a significant number of these floating party workers have joined BJP. Also Read – Heavy rain hits traffic, flightsThe Panchayat election has witnessed an unprecedented number of Independent candidates. A total of 16,880 candidates are contesting in the Panchayat election. This is more than the number of candidates filed by Congress. Party of Democratic Socialism (PDS), CPI-ML (Liberation) and SUCI have filed their nominees as Independent candidates. Their collective strength will be around 880. The remaining 16,000 candidates are all members of various political parties. They are contesting the election without a party symbol. Political analysts said in many areas BJP is not contesting in its official symbol and has nominated an Independent candidate. CPI-M and Congress have towed this line. In Gram Panchayat, where the number of voters is less and every vote matters, fielding an independent candidate will put pressure on the ruling party.last_img read more

18 arrested in Kolkata for running brothel

first_imgKolkata: Police busted a sex racket and arrested 18 persons including nine sex workers from Kolkata’s Park Street area, a senior officer said on Sunday. Acting on a tip off, officers of Beniapukur Police Station conducted a raid on the third floor of a building in 82 Park Street on Saturday evening and arrested the persons for allegedly running a brothel in the guise of a beauty parlour. “Nine sex workers, three customers and six other persons including the pimps and brothel manager Bikash Chakraborty were arrested,” Joint Commissioner of Kolkata Police (Crime) Nishad Parvez said.last_img

Presidency varsity fails to meet handover deadline

first_imgKolkata: Presidency University (PU) has failed to meet the November 15 deadline given by the state Higher Education department with regard to the handover of Hindu Hostel. PU Vice-Chancellor Anuradha Lohia has sought another 15 days’ time for completing some work pertaining to the habitationof the students. State Education minister Partha Chatterjee has summoned the university authorities on Monday and asked for an explanation behind the delay. On being questioned about the inability to meet the deadline over the handover, PU V-C Anuradha Lohia said: “We had not set any deadline. The government had given a deadline. I had said mentioned that the entire work will be finished off by January. We tried our best to stick to it and everybody involved in the construction worked hard even during Durga Puja and Diwali but could not complete the work. We hope to complete the entire work by November 30.” According to the V-C, the state Public Works Department (PWD) that is in-charge of the renovation of the hostel has submitted a report stating that a little bit of work is still pending when it comes to the safety and security of the boarders. “We are also awaiting the certificates of safety from the state Fire and PWD departments,” Lohia added. A senior official of PU pointed out some areas where work is still pending. The dining room and the kitchen need some more work. Some broken glasses are scattered here and there which need to be removed. “We will put LPG gas to use for cooking and do away with diesel that was earlier used for the purpose. We are creating a gas bank for this,” the official said. It may be mentioned that the Hindi Hostel was closed for renovation in July 2015 and the boarders were provided with lodging facilities at Tarulia in New Town. The university has failed to meet deadlines on more than one occasion in case of Hindu Hostel handover. The students had resorted to agitation for a long period demanding the same.last_img read more