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Archives for: August 31, 2019

General Electric Develops a 500GB Optical Disc

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first_img Pioneer to Ship PC-Based Blu-ray Disc Drive in Q1 2006 Micro-holographic discs have a larger storage capacity than DVDs or Blu-ray because they store information on the disc in three dimensions, rather than just pits on the surface of the disc. G.E. has recently made dramatic improvements in the material that significantly increases the amount of light that can be reflected by the holograms. By increasing the reflectivity of the disc you increase the storage capacity. This will enable players to be built which are backwards compatible with existing DVD and Blu-ray technologies.In a statement, from G.E.: “the hardware and formats are so similar to current optical storage technology that the micro-holographic players will enable consumers to play back their CDs, DVDs and Blu-ray discs.”G.E. also added: “the day when you can store your entire high definition movie collection on one disc and support high resolution formats like 3D television is closer than you think.” GE will need to work with hardware manufacturers to bring the technology to the consumer market.Micro-holographic technology is truly a breakthrough in the development of the materials that are so critical to ultimately bringing holographic storage to the everyday consumer.General Electric’s first priority will be to target the technology to commercial markets like television networks, movie studios, medical field and hospitals for holding data-intensive images. However selling to the broader corporate and consumer market is the larger goal.© 2009 PhysOrg.com (PhysOrg.com) — G.E. has unveiled a 500 GB micro-holographic disc that is the same size as existing DVD’s. The storage capacity is equivalent to 100 DVD’s and is aimed at the archive industry but eventually can be used in the consumer market place. 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.center_img Citation: General Electric Develops a 500GB Optical Disc (2009, April 27) retrieved 18 August 2019 from https://phys.org/news/2009-04-electric-500gb-optical-disc.html Explore furtherlast_img read more

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Researchers develop method of fabricating perovskite solar cells that is more efficient

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first_imgCross-sectional FESEM image of the device consisting of FTO-Glass/bl-TiO2/mpTiO2/perovskite/PTAA/Au. Credit: Science, DOI: 10.1126/science.aaa9272 © 2015 Tech Xplore Journal information: Science 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. Perovskite solar cell reaches record efficiency As scientists have reached what appears to be the efficiency limit for solar cells based on silicon, the search has been on for a material to replace it, one that is at least as efficient, cost effective and will last for as long as possible. One such material perovskite, has been making headlines of late, as researchers have been improving its solar efficiency rating at a remarkable pace, from 14 percent in 2012, to 20 percent last year (the fastest that a solar technology has ever advanced). Now, it appears that mark has been raised again by the same team in Korea.Perovskite is a mineral made of calcium titanate—its use in solar cells is mostly found as a hybrid organic-inorganic lead as part of the active (light-harvesting) layer. It does not need to go through the multi-step process seen with silicon to be used in making solar cells, nor require the clean room, high temperature or a vacuum. The new process developed by the team in Korea involves placing a lead iodide–dimethylsulfoxide layer onto a formamidinium iodide solution—which causes the formation of a formamidinium lead iodide perovskite composition. The result is a more efficient cell as it allows for gathering a broader spectrum of light. Thus far, the team reports that cells made with their new method have reached efficiencies of up to 20.2 percent. They also claim that their method also allows for producing the cells more cheaply than other fabrication methods.What is still not clear is how well such cells can stand up to environmental conditions over long periods of time—some other recent research by other teams has suggested they may not be able to maintain their efficiencies over reasonable timescales. Still, because of its promise, several start-ups have promised sales of such cells to consumers as early as 2017.center_img More information: High-performance photovoltaic perovskite layers fabricated through intramolecular exchange, Science, DOI: 10.1126/science.aaa9272ABSTRACTThe band gap of formamidinium lead iodide (FAPbI3) perovskites allows broader absorption of the solar spectrum compared to conventional methylammonium lead iodide (MAPbI3). The optoelectronic properties of perovskite films are closely related to the film-quality, so depositing dense and uniform films is crucial for fabricating high-performance perovskite solar cells (PSCs). We report an approach for depositing high-quality FAPbI3 films, involving FAPbI3 crystallization by the direct intramolecular exchange of dimethylsulfoxide (DMSO) molecules intercalated in PbI2 with formamidinium iodide. This process produces FAPbI3 films with (111)-preferred crystallographic orientation, large-grained dense microstructures, and flat surfaces without residual PbI2. Using films prepared by this technique, FAPbI3-based PSCs with maximum power conversion efficiency of over 20% were fabricated. Explore further Citation: Researchers develop method of fabricating perovskite solar cells that is more efficient, costs less (2015, May 22) retrieved 18 August 2019 from https://phys.org/news/2015-05-method-fabricating-perovskite-solar-cells.html (Phys.org)—A team of researchers working at the Korea Research Institute of Chemical Technology in South Korea, has found a way to make fabricating perovskite based solar cells that is both more efficient and costs less than other current methods. In their paper published in the journal Science, the team describes their process and the efficiencies they were able to achieve.last_img read more

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Astronomers observe a unique multiplylensed supernova

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first_img Hubble captures first-ever predicted exploding star The MACS J1149.6+2223 field, showing the positions of the three primary images of the SN Refsdal host galaxy (labeled 1.1, 1.2 and 1.3). SN Refsdal appears as four point sources in an Einstein Cross configuration in the southeast spiral arm of image 1.1. The highlighted box is shown at the same scale in panels on the right side, which illustrate the removal of contaminating diffraction spikes from a difference image. Each difference image is centered on the location of the contaminating star (top panel), then rotated clockwise by 90 degrees (middle panel). The rotated difference image is then subtracted from the initial difference image, removing most of the flux from the contaminating diffraction spike at the location of the SN Refsdal point sources (bottom panel). Credit: Steven A. Rodney et al., 2015. 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. © 2016 Phys.org More than a year ago, four images of SN Refsdal were detected by Hubble as part of the Grism Lens-Amplified Survey from Space (GLASS) program. GLASS acquires near-infrared grism spectra of massive galaxy clusters with the primary goals of studying faint, high-redshift galaxies and spatially resolved intermediate-redshift galaxies, as well as characterizing the cluster galaxy population. The images obtained by Hubble show SN Refsdal shining brightly from the arm of a spiral galaxy that lies far beyond another galaxy between the supernova and our planet. SN Refsdal as a background source is strongly lensed by galaxies and a galaxy cluster massive enough to bend the light into multiple images.The astronomers then predicted that the supernova will soon reappear in the cluster field. Their predictions were correct, as SN Refsdal reappeared once more between mid November and Dec. 11, 2015. The exact date is uncertain by approximately one month, which is the interval between two consecutive Hubble observations.This reappearance was a great occasion for a team of scientists led by Steven A. Rodney from the University of South Carolina to sum up the findings since previous sightings of SN Refdal in 2014. Moreover, the team managed to measure time delays for the four images obtained over a year ago.The researchers found that the observed shape of SN Refsdal has distinct similarities with supernova SN 1987A. They also noted that the studied supernova is most likely a member of the peculiar Type II sub-class defined by the SN 1987A prototype.To conduct precise measurements of relative time delays and also magnification ratios from the SN Refsdal data, the scientists used two methods: light curve template matching and flexible polynomial light curve models. They constructed their models based on supernovae like SN 1987A, which has a well-sampled light curve coverage. The researchers note that the use of two different methods yields complementary results.”Even the best fit, template-based model shows systematic residuals and does not provide a good representation of the observed data. SN Refsdal is not quite a clone of other observed 87A-like Type II supernovae. Thus, as a second approach for measuring the time delays between the four Refsdal sources, we used a series of flexible light curve models—splines and polynomials—to represent the underlying light curve shape. By adopting these free-form curves in place of the rigid SN light curve templates, we can derive time delays that are agnostic about the classification of SN Refsdal,” the astronomers wrote in the paper.Rodney and his team determined these time delays with a precision of two to eight days. According to their study, the time delay between the first and the fourth image is about 26 days.”This level of precision is promising, as it suggests that a similarly cadenced monitoring campaign could deliver a relative precision of 1 percent on the time delay to the next image,” the paper reads.SN Refsdal, as the first multiply-imaged supernova ever seen, will be a target of numerous observations conducted by scientists studying lens modeling methods. The researchers concluded that with a sufficiently rapid observational cadence and concerted lens modeling efforts, it will be feasible to use measurements of these lensed time delays as cosmographic tools. Cluster-lensed supernovae such as SN Refsdal could, indeed, contribute to future time delay cosmography efforts. (Phys.org)—SN Refsdal is a peculiar supernova visible within the field of the galaxy cluster MACS J1149+2223. Discovered in November 2014 using the Hubble Space Telescope, this supernova is the first that was seen multiple times thanks to gravitational lensing. Now, an international team of astronomers has published a paper on Jan. 15 summarizing one year of Hubble observations of SN Refsdal. The research is available online on the arXiv pre-print server. More information: SN Refsdal : Photometry and Time Delay Measurements of the First Einstein Cross Supernova, arXiv:1512.05734 [astro-ph.CO] arxiv.org/abs/1512.05734AbstractWe present the first year of Hubble Space Telescope imaging of the unique supernova (SN) ‘Refsdal’, a gravitationally lensed SN at z=1.488±0.001 with multiple images behind the galaxy cluster MACS J1149.6+2223. The first four observed images of SN Refsdal (images S1-S4) exhibited a slow rise (over ~150 days) to reach a broad peak brightness around 20 April, 2015. Using a set of light curve templates constructed from SN 1987A-like peculiar Type II SNe, we measure time delays for the four images relative to S1 of 4±4 (for S2), 2±5 (S3), and 24±7 days (S4). The measured magnification ratios relative to S1 are 1.15±0.05 (S2), 1.01±0.04 (S3), and 0.34±0.02 (S4). None of the template light curves fully captures the photometric behavior of SN Refsdal, so we also derive complementary measurements for these parameters using polynomials to represent the intrinsic light curve shape. These more flexible fits deliver fully consistent time delays of 7±2 (S2), 0.6±3 (S3), and 27±8 days (S4). The lensing magnification ratios are similarly consistent, measured as 1.17±0.02 (S2), 1.00±0.01 (S3), and 0.38±0.02 (S4). We compare these measurements against published predictions from lens models, and find that the majority of model predictions are in very good agreement with our measurements. Finally, we discuss avenues for future improvement of time delay measurements—both for SN Refsdal and for other strongly lensed SNe yet to come. Citation: Astronomers observe a unique multiply-lensed supernova (2016, January 19) retrieved 18 August 2019 from https://phys.org/news/2016-01-astronomers-unique-multiply-lensed-supernova.html Explore furtherlast_img read more

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The conscience call

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first_imgThe book will be launched by chief guest Member of Parliament LK Advani and and Guest of Honor Jawed Naqvi.Historic Temples in Pakistan: A Call to Conscience makes a case for keeping ancient emblems of faith alive and for pluralism in a land of irony that has been home to multiple ancient faiths yet stands besieged by unpalatable extremism. It also aspires to enshrine the ideal of liberty. By framing an all-inclusive piety, this book sets out to ignite a discourse and the collective conscience of a nation numbed into silence, fear or the false conviction of the supremacy of a singular religion – to institutionalise the fundamental right of will.  Also Read – ‘Playing Jojo was emotionally exhausting’Elaborately embellished with evocative photographs of antiquated and exquisite Hindu shrines, opulent rituals and festivals and regional populace, the chronicle has extensive research and exceptional pilgrimage sites – Hinglaj, Katas Raj, Kalka Cave Temple, Panchmukhi Hanuman Mandir and Shivala Mandir, to name a few. While vivid introductions and sweeping images present the landscape and the social fabric of a territory, the redolence of celebrations spread passion and fervour. A special article introduces the extraordinary Fakira, last of the human hands behind idols in Pakistan. Humanity is cast as the oldest of creeds and as the reason for faiths. Therefore, devotion cannot be reserved for a sole call to prayer.WHEN:  23 July, 6:30 pmWHERE: India International Centre Seminar Hall 1, 2 & 3last_img read more

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Trinamool Congress leading in gram panchayat seats

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first_imgKolkata: The ruling Trinamool Congress today surged ahead in 1,800 gram panchayat seats while the BJP and the CPI(M) were leading in 100 and 30 gram panchayat seats respectively, as per initial trends available at 10 am, SEC officials said. The panchayat elections were held for 621 zilla parishads, 6,123 panchayat samitis and 31,802 gram panchayats in West Bengal on May 14. The counting of votes began at 8 am amid tight security, the State Election Commission officials said. Of the 48,650 seats in 3,358 gram panchayats, 16,814 were uncontested and of the 9,217 seats in 341 panchayat samitis, 3,059 were uncontested. In the 20 zilla parishads, 203 of the 825 seats were uncontested, the sources said.last_img

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One killed many injured in clash in CoochBehar

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first_imgCoochBehar(WB): One person was killed and a number of people were injured in a clash between supporters of two political parties in CoochBehar district, police said today. The clash between the supporters of the two parties took place at Jamaldaha area of the district yesterday in which Ramjan Mian was killed and many people were injured, they said.The police, however, did not specify the number of injured persons.A large contingent of police force was deployed in the area to maintain peace, they added. Also Read – Heavy rain hits traffic, flightsCoochBehar district CPI(M) leaders claimed that deceased Ramjan Mian was their active supporter and their newly elected gram panchayat member of Jamaldaha, Atabul Islamd was among the injured.The CPI(M) leaders alleged that the clash started when Trinamool Congress workers tried to set the house of Islam on fire which was resisted by CPI(M) activists.The Trinamool Congress has denied the CPI(M) allegations.last_img read more

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BJP trying to disturb peace and stability of Bengal TMC

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first_imgKolkata: The ruling Trinamool Congress today accused the state BJP of trying to disturb the peace and stability of West Bengal by making provocative statements against its cadre. TMC secretary general Partha Chatterjee said the BJP for the last few years have been trying to disturb peace and stability in the state. “They have been doing such things just to gain political foothold in Bengal. But the people of Bengal will never accept a party which propagates communal division,” he said. Also Read – Heavy rain hits traffic, flights Chatterjee said, “First they(BJP) tried their hand in creating communal tensions and now they are making provocative statements. But they won’t succeed in their intensions.” Chatterjee’s comment comes in the backdrop of West Bengal BJP president Dilip Ghosh recent utterance that his party would not take it lying down if its workers were attacked by the TMC. Threatening “direct encounters,”, he had said “We are counting the bullets which killed our workers.” Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killed “We have seen many goondas. There is a limit to tolerance (to such attacks). We have not given any bond that we will offer them (TMC) rasogolla (sweet) even if they attack us. There will be retaliation”, Ghosh had said at a public meeting in north Bengal on June 19. Hitting back, Chatterjee said the BJP is “miles away” from the seat of power in West Bengal and is threatening to launch encounters. “From such statements the people of Bengal can understand the kind of intolerant outfit BJP is,” he added. Chief Minister and TMC supremo Mamata Banerjee had yesterday called BJP a “militant organisation,” and alleged that it is engaged in dividing the people along religious lines while daring it to attack her party. “We are not a militant organisation like the BJP. They are arrogant and intolerant. They are religiously biased. They don’t like Muslims, Christians, Sikhs – they are even differentiating between the upper caste and the lower caste Hindus,” Banerjee, a known critic of the saffron party, had said at the extended core committee meeting of the TMC. Lashing out at the BJP, she had said, “They (BJP) are threatening to carry out encounters. Just because they are in power in Delhi, they are talking about hurling bombs. I dare them to come and touch us. We will show them their place.”last_img read more

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SIT to seek expert opinion for causes of Majerhat bridge cavein

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first_imgKolkata: Expert opinion will be sought in regard to the causes of the collapse of the Majerhat bridge, Joint Commissioner of Police (Crime) Praveen Tripathi informed on Thursday.He also said the Public Works Department (PWD) had given a No Objection Certificate (NOC) to the Rail Vikas Nigam Limited (RVNL).According to sources, Kolkata Police had formed a Special InvestigationTeam (SIT) two days after the bridge caved-in. Later the SIT asked the Metro authority and PWD to submit all the relevant documents they had regarding the same. Also Read – Rain batters Kolkata, cripples normal lifeOn Thursday, Tripathi informed that the PWD authority was asked to provide all documents related to the maintenance work, construction and other necessary papers in this regard which they have complied with.As per the list, copy of a NOC is also there that was given to the RVNL. He also informed that the Metro authority also submitted certain documents. More will be provided soon by them. “We will now sort the documents and scrutiny all of them thoroughly,” said Tripathi.The SIT will also engage an expert agency for opinion. According to police, they may engage the Indian Institute of Technology (IIT) Kharagpur or IIT Roorkee for the same. Their main objective is to gather information about the structural engineering part which may provide assistance to detect the cause of the collapse of the Majerhat bridge.last_img read more

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SC to hear plea challenging WBs decision to grant funds for Durga

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first_imgNew Delhi: The Supreme Court Thursday agreed to hear tomorrow an appeal challenging the West Bengal government’s decision to grant Rs 10,000 each to puja committees in the state for Durga Puja celebrations. A bench headed by Chief Justice Ranjan Gogoi was apprised that on Wednesday the Calcutta High Court had refused to interfere with the Mamata Banerjee government’s decision to grant money to Puja committees in the state. The bench also comprising Justices S K Kaul and K M Joseph was told by lawyer Saurav Dutta, who had filed an appeal against the high court’s decision, that the decision of the state government was against the established principle of law and sought an urgent hearing on his plea.last_img

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Soon all Kisan Mandis to have machine to dry up moisture from

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first_imgKolkata: State Agriculture and Food and Supplies department have decided to install an advanced machine at all the Kisan Mandis run by the state government to dry up moisture in rice and remove the dust particles from the grains to save farmers from being hoodwinked by the rice mill owners.State Agriculture minister Asish Banerjee and Food and Supplies minister Jyotipriya Mallick will hold a high-level meeting with senior officials of their departments at Khadya Bhawan on January 10 to lay out a comprehensive strategy and roadmap to ensure that the paddy farmers get the price as fixed by the state government. Also Read – Rain batters Kolkata, cripples normal lifeIt has been alleged that the go-down owners or Arotdars often force the farmers to believe that huge amounts of moisture and dust particles are found in the grains. This happens only because there is no proper machine that can dry up the moisture and separate the dust from rice and other food grains. This practice often leads to a huge loss for the cultivators. Keeping this in view, the Agriculture and Food and Supplies departments have come up with an idea of installing machines at Kisan Mandis so that the farmers get proper price for their produce. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedThe new machines will be installed at the Kisan Mandis where the farmers can separate the moisture of rice, isolate the dust from grains and get adequate price for their produce. The machine will also help them to weigh their produce before selling them. It may be mentioned that both the departments have started distributing cheques among the farmers in all the districts and there has been a huge response so far. Following the instructions of Chief Minister Mamata Banerjee, both the departments have already started a crackdown on the middlemen who have been causing difficulties in the procurement of paddy from the farmers. Banerjee expressed her concern over the middlemen menace during her recent meeting at Nabanna in December and issued necessary instructions in this regard. Both the Agriculture and Food and Supplies Department have started a massive crackdown on the middlemen in all the districts to iron out the earlier practice that had been prevailing in the state so far. The Chief Minister also reiterated the position of her government saying that they wanted to procure directly from the farmers thereby increasing the target of the overall paddy procurement in the state.last_img read more

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