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Characteristic analysis of layered PMSEs measured with different elevation angles at VHF based on an experimental case 认领
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作者 ShuCan Ge HaiLong Li +8 位作者 Bin Xu Tong Xu Lin Meng MaoYan Wang Abdel Hannachi MengYan Zhu Lina Broman Safi Ullah Abdur Rauf 《地球与行星物理:英文版》 2021年第1期42-51,共10页
Polar Mesosphere Summer Echoes(PMSEs)are very strong radar echoes observed at altitudes near the polar summer mesopause.One of the essential properties of these radar echoes is that they can give useful diagnostic inf... Polar Mesosphere Summer Echoes(PMSEs)are very strong radar echoes observed at altitudes near the polar summer mesopause.One of the essential properties of these radar echoes is that they can give useful diagnostic information about the physics of the scattering process.In this paper,the related characteristics of PMSEs measured with the European Incoherent SCATter Very High Frequency(EISCAT VHF)224 MHz radar on 13–15 July 2010 are studied at different elevation angles from 78°to 90°.It is found that the PMSEs peak power and strongest PMSEs average power occur at the same elevation angles.Also interesting is that the strongest PMSEs occur at off-vertical angles when a PMSEs has a layered(multilayer)structure.And reflection may have more significant effects on PMSEs when there are double or multilayer PMSEs.Possible explanations regarding these observations are discussed. 展开更多
关键词 Polar Mesosphere Summer Echoes off-vertical angles layered structure
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Dielectric permittivity of dusty plasma in the Earth's mesosphere 认领
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作者 Hui Li Jian Wu 《地球与行星物理:英文版》 2021年第1期117-120,共4页
This paper deals with the dielectric permittivity of dusty plasma in the earth’s mesosphere.We give expressions for the complex dielectric permittivity of dusty plasma,taking into account the effects of the dust char... This paper deals with the dielectric permittivity of dusty plasma in the earth’s mesosphere.We give expressions for the complex dielectric permittivity of dusty plasma,taking into account the effects of the dust charging process and magnetic field.We discuss the dielectric permittivity of dusty plasma in several cases,such as high frequency approximation,parallel propagation in MF/HF band,and effects of plasma movement.Finally,the expressions are employed to study the phenomenon of radar echoes from the polar summer mesosphere.We report that dielectric permittivity caused by the dust charging process gives a radar cross section proportional to ω–4 and produces a number density of charged dust that agrees with measurements of mesopheric radar echoes. 展开更多
关键词 dusty plasma dielectric permittivity polar summer mesosphere
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基于Polar WRF的南极Dome A极端低温事件分析 认领
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作者 王一丞 谢爱红 +1 位作者 丁明虎 效存德 《冰川冻土》 CSCD 北大核心 2020年第3期727-733,共7页
南极作为地球的寒极,其最高点Dome A地区于2013年8月1日气温达到-93.0℃的极低值。利用Polar Weather Research and Forecasting(Polar WRF)3.8.1模式,对发生在南极Dome A地区的3次极端低温事件进行数值模拟分析。通过与自动气象站实测... 南极作为地球的寒极,其最高点Dome A地区于2013年8月1日气温达到-93.0℃的极低值。利用Polar Weather Research and Forecasting(Polar WRF)3.8.1模式,对发生在南极Dome A地区的3次极端低温事件进行数值模拟分析。通过与自动气象站实测数据对比验证,模拟效果较为理想。结果表明:印度洋和大西洋交界区域的高压加强,其高压脊开始向南极内陆延伸,导致Dome A地区气压升高,使得该地区天气晴好,云量极低,为极端低温事件发生奠定基础;同时,南极中心冷涡加强,长时间的冷平流和稳定的逆温层为Dome A地区提供了足够的降温条件,并且加强了夜间辐射降温效应,稳定的垂直场、极低的向下长波辐射使得Dome A地区的极端低温事件得以维持。 展开更多
关键词 南极 Dome A 极端低温 Polar WRF模式
Improved Polar Decoder Utilizing Neural Network in Fast Simplified Successive-Cancellation Decoding 认领
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作者 Jiaxin Fang Chunwu Liu 《电脑和通信(英文)》 2020年第7期90-99,共10页
<div style="text-align:justify;"> Polar codes using successive-cancellation decoding always suffer from high latency for its serial nature. Fast simplified successive-cancellation decoding algorithm im... <div style="text-align:justify;"> Polar codes using successive-cancellation decoding always suffer from high latency for its serial nature. Fast simplified successive-cancellation decoding algorithm improves the situation in theoretically but not performs well as expected in practical for the workload of nodes identification and the existence of many short blocks. Meanwhile, Neural network (NN) based decoders have appeared as potential candidates to replace conventional decoders for polar codes. But the exponentially increasing training complexity with information bits is unacceptable which means it is only suitable for short codes. In this paper, we present an improvement that increases decoding efficiency without degrading the error-correction performance. The long polar codes are divided into several sub-blocks, some of which can be decoded adopting fast maximum likelihood decoding method and the remained parts are replaced by several short codes NN decoders. The result shows that time steps the proposed algorithm need only equal to 79.8% of fast simplified successive-cancellation decoders require. Moreover, it has up to 21.2 times faster than successive-cancellation decoding algorithm. More importantly, the proposed algorithm decreases the hardness when applying in some degree. </div> 展开更多
关键词 Polar Codes Decoding Latency Fast Simplified Successive-Cancellation Decoding (Fast-SSC) Neural Network (NN)
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RETRACTED: <i>Improved Polar Decoder Utilizing Neural Network in Fast Simplified Successive-Cancellation Decoding</i> 认领
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作者 Jiaxin Fang Chunwu Liu 《光学与光子学期刊(英文)》 2020年第6期149-158,共12页
<div style="text-align:justify;"> <p style="text-align:justify;background:white;"> <span style="font-size:10.0pt;font-family:" color:black;"="">This artic... <div style="text-align:justify;"> <p style="text-align:justify;background:white;"> <span style="font-size:10.0pt;font-family:" color:black;"="">This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's </span><span><a href="http://publicationethics.org/files/retraction%20guidelines.pdf"><span style="font-size:10.0pt;font-family:;" "="">Retraction Guidelines</span></a></span><span style="font-size:10.0pt;font-family:" color:black;"="">. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused.</span><span style="font-size:10.0pt;font-family:" color:black;"=""></span> </p> <p style="text-align:justify;background:white;"> <span style="font-size:10.0pt;font-family:" color:black;"="">Please see the </span><span><a href="https://www.scirp.org/journal/paperinformation.aspx?paperid=101825"><span style="font-size:10.0pt;font-family:;" "="">article page</span></a></span><span style="font-size:10.0pt;font-family:" color:black;"=""> for more details. </span><span><a href="https://www.scirp.org/pdf/opj_2020072814494052.pdf"><span style="font-size:10.0pt;font-family:;" "="">The full retraction notice</span></a></span><span style="font-size:10.0pt;font-family:" color:black;"=""> in PDF is preceding the original paper which is marked "RETRACTED". </span> </p> <br /> </div> 展开更多
关键词 Polar Codes Decoding Latency Fast Simplified Successive-Cancellation Decoding (Fast-SSC) Neural Network (NN)
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Interest of Splitting the Enthalpies of Vaporization in Four Distinct Parts Reflecting the Van der Waals and the Hydrogen Bonding Forces 认领
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作者 Paul Laffort 《物理化学期刊(英文)》 2020年第2期117-137,共21页
An experimental characterization of the Van der Waals forces involved in volatile organic compounds (VOC) dissolved into stationary phases of gas liquid chromatography (GLC) has been started at the beginning of the se... An experimental characterization of the Van der Waals forces involved in volatile organic compounds (VOC) dissolved into stationary phases of gas liquid chromatography (GLC) has been started at the beginning of the seventies. This field has been reactivated from 1994 thanks to a fruitful cooperation between our CNRS team and the group of Ervin Kováts at the Federal Polytechnic School of Lausanne. The applied strategy can be summarized, in the first instance, as the experimental measurement of accurate and superabundant mutual affinities of a limited number of VOC and stationary phases and their processing using an original tool named Multiplicative Matrix Analysis (MMA). Then, in the second stage, the obtained results have been compared with molecular properties well established, as the Van der Waals molecular volume, the refraction index and the polar surface area (PSA), in order to get generalized values for any compound. The present study summarizes the positive results developed in our three last papers on this topic (2013, 2016 and 2018), as well as the attempt to overcome the negative ones using enthalpies of vaporization. 展开更多
关键词 Enthalpy of VAPORIZATION Van der WAALS Intermolecular FORCES Molecular Polarity Polar Surface Area GAS-LIQUID Chromatography Chemo-Informatics OLFACTION
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TCN网关高速PCB设计研究 认领
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作者 石小磊 阎东 周达 《铁道机车与动车》 2020年第2期10-13,17,I0003共6页
讨论高速PCB设计中的延时、反射、串扰、振铃等信号完整性问题,针对TCN网关CPU板的400 MHz DDR时钟差分信号模型,结合Polar SI9000工具进行差分特性阻抗分析和计算,设置合适的约束规则控制PCB布局布线,从各个环节保证差分信号的阻抗匹... 讨论高速PCB设计中的延时、反射、串扰、振铃等信号完整性问题,针对TCN网关CPU板的400 MHz DDR时钟差分信号模型,结合Polar SI9000工具进行差分特性阻抗分析和计算,设置合适的约束规则控制PCB布局布线,从各个环节保证差分信号的阻抗匹配和高速电路的信号完整性。 展开更多
关键词 信号完整性 差分特性阻抗 阻抗匹配 高速PCB POLAR SI9000 PCB布线约束
比赛教学法对大学篮球课程教学质量的影响 认领
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作者 任屹奕 全海英 《辽宁师专学报:自然科学版》 2020年第2期56-61,共6页
为了与新时代中国体育课程标准接轨,运用文献综述法、直接访谈法、实验法、数理统计法探讨比赛教学法对大学篮球课程教学质量的影响.将40名学生分为实验组和对照组,使用Polar Team 2团队心率仪监测运动数据变化.结果表明,实验组与对照... 为了与新时代中国体育课程标准接轨,运用文献综述法、直接访谈法、实验法、数理统计法探讨比赛教学法对大学篮球课程教学质量的影响.将40名学生分为实验组和对照组,使用Polar Team 2团队心率仪监测运动数据变化.结果表明,实验组与对照组学生的前测结果不具有显著差异;采用比赛教学法后实验组学生身体活动强度指标较对照组学生具有非常显著性差异;实验组学生身体活动强度指标的前测和后测结果呈现显著性差异,期末测试成绩明显提高,课程体验满意度较高.该研究表明,比赛教学法可以显著提高大学篮球课程教学质量,值得推广. 展开更多
关键词 篮球课程 比赛教学法 Polar Team 2 教学质量 运动强度
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基于Light Fidelity在智慧环境的运用 认领
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作者 陈虹旭 于川岳 +3 位作者 李晓坤 刘清源 孙怡然 董潍赫 《软件》 2020年第9期137-140,144,共5页
智慧环境,作为互联网技术与环境信息化技术的结合体,显然需要多种多样的信息与数据传输手段,将智慧环境与Light Fidelity技术相结合,更利于环境信息化管理。针对Light Fidelity在智慧环境运用过程中存在的"阴影效应"问题进行... 智慧环境,作为互联网技术与环境信息化技术的结合体,显然需要多种多样的信息与数据传输手段,将智慧环境与Light Fidelity技术相结合,更利于环境信息化管理。针对Light Fidelity在智慧环境运用过程中存在的"阴影效应"问题进行探讨与研究,提出基于Haar小波的DWT-OFDM的调制解决方案。同时,分析Polar Code在基于OOK技术的Light Fight通信运用中存在的优势,建立Light Fidelity在智慧环境中的通信系统模型,分析在总衰减系数不同的情况下,Light Fidelity的接收光功率与通信距离的变化关系,并采用加权系数法,优化Light Fidelity路径损耗的计算以及Light Fidelity在智慧环境中的通信性能。 展开更多
关键词 Light Fidelity 智慧环境 Haar DWT-OFDM Polar Code
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文章速递Prediction Method of Ice Resistance and Propulsion Power for Polar Ships 认领
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作者 丁仕风 周利 +1 位作者 王峥嵘 TSUPRIK Vadimir G. 《上海交通大学学报:英文版》 EI 2020年第6期739-745,共7页
Polar ships need to meet stringent safety and environmental requirements.Usually those ships are classified by diferent ice classes based on ice operation capability.However,the polar ships are also trapped by severe ... Polar ships need to meet stringent safety and environmental requirements.Usually those ships are classified by diferent ice classes based on ice operation capability.However,the polar ships are also trapped by severe ice condition due to low propulsion power.Therefore,it is a realistic question to design the appropriate minimum propulsion power for ice operation.This paper focuses on the ice resistance and its related propulsion power for the ships with polar code(PC)classes.In consideration of seven typical polar ice conditions related to the PC rule of International Association of Classification Societies(IACS),a prediction method of ice resistance is developed by Lindqvist's model.The results are compared with those of Lindqvist's model and Riska's model by using two real ship lines.The comparison among propulsion requirements of representative classification societies is made,and a formula of minimum propulsion power is presented on the basis of ice resistance by revised Finnish-Swedish Ice Class Rules(FSICR)method.The results are verified by the actual values from seven ice class ships.A relatively good agreement is achieved.As a conclusion,the presented prediction method of ice resistance and minimum propulsion power is recommended for evaluation of ice resistance and its related propulsion power during the process of developing polar ships. 展开更多
关键词 polar ship evel ice ice resistance propulsion power ship classification
文章速递Unexpected Electronic Behavior of Organic Azide and Metal-Carbynein Their 1,3-Dipolar Cycloaddition Reaction 认领
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作者 Jing-Xuan Zhang Fu Kit Sheong +2 位作者 Zhengyu Lu Hong Zhang Zhenyang Lin 《中国化学:英文版》 SCIE CAS CSCD 2020年第12期1565-1570,共6页
of main obsevation and conclusion 1,3-Dipolar aycloaddition reaction between organic azide and metal carbyne is a useful strategy to con-struct metallacycles.However,the electronic behavior of organic azide in 1,3-dip... of main obsevation and conclusion 1,3-Dipolar aycloaddition reaction between organic azide and metal carbyne is a useful strategy to con-struct metallacycles.However,the electronic behavior of organic azide in 1,3-dipolar aycloaddition reactions is less explored.Tthis work revealed theunexpected role of organic azide as electrophiles in its cycloaditions with various metal carbynes.The feasility and regioselectivity of a Fischer-typeosmiun carbyne in its reaction with an organic azide are explained by the increased nucleophilicity of carbyne carbon upon bending. 展开更多
关键词 azide polar addition
文章速递主变倒送电冲击时低压侧接地变二次侧电缆熔毁事故分析 认领
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作者 唐海燕 胡学海 王辉 《电工技术》 2020年第23期130-132,135,共4页
电厂倒送电是新建电厂调试期间的重点工作。对#2机组主变倒送电期间发生的低压侧接地变二次电缆熔毁事故进行分析,给出了事件经过及现场录波波形。根据500 kV断路器合闸后出现三相电压不平衡现象,分析出事件的初步原因为二次绕组短路或... 电厂倒送电是新建电厂调试期间的重点工作。对#2机组主变倒送电期间发生的低压侧接地变二次电缆熔毁事故进行分析,给出了事件经过及现场录波波形。根据500 kV断路器合闸后出现三相电压不平衡现象,分析出事件的初步原因为二次绕组短路或变压器极性接反。进一步在理论上针对初步原因进行分析,结合实际测量结果,判断主变低压侧接地变极性接反导致发热引起电缆绝缘受损。通过该事件,对电厂设计、设备验收管理和调试提出了改进建议。 展开更多
关键词 倒送电 接地变 电缆 极性
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5G通信中的Polar码专利申请分析 认领
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作者 杜东振 邹丽 《科技与创新》 2020年第24期9-10,14,共3页
Polar码是学术界研究热点之一,各大公司对Polar码的潜力有共识,并投入了大量研发力量对其在5G中应用方案进行深入研究、评估和优化,且重视相关专利的布局。对Polar码的相关专利申请进行统计分析,得出该技术的研究趋势并给出相关建议。
关键词 第五代移动通信技术 POLAR 专利 运营商
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Effects of the sunscreen ultraviolet filter,oxybenzone,on green microalgae 认领
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作者 Ming-Li TEOH Nur Suhaida SANUSI +1 位作者 Ching-Yee WONG John BEARDALL 《极地科学进展:英文版》 CSCD 2020年第2期112-123,共12页
Ultraviolet(UV)filters are widely used in sunscreen and personal care products due to their ability to give protection to our skin from UV radiation.Oxybenzone,commonly known as benzophenone-3,is one type of UV filter... Ultraviolet(UV)filters are widely used in sunscreen and personal care products due to their ability to give protection to our skin from UV radiation.Oxybenzone,commonly known as benzophenone-3,is one type of UV filter found as the active ingredient in many pharmaceutical products.Although oxybenzone has been extensively studied as an environmental toxicant in the ecosystem,little is known about its toxicity effects on microalgae.The effects of oxybenzone on growth(measured as OD620 nm,chlɑand carotenoids)and macromolecular composition of polar microalgae(Chlorella UMACC 400 and Chlorella UMACC 401)and temperate microalgae(Chlorella sp.,Chlamydomonas reinhardtii,Scenedesmus quadricauda)were investigated.These microalgae were cultured in triplicate and exposed to different oxybenzone concentrations(0,100,200,300 and 400 mg·L-1),at 4℃and 18 for polar and temperate species respectively,for 96 h.The oxybenzone concentrations used℃represent a range from environmental to extreme concentrations to understand the impact of this toxicant on microalgae.The results showed that the highest concentration of oxybenzone(300 and 400 mg·L-1)had adverse effects on growth rate and biomass of these microalgae.However,exposure to oxybenzone concentrations ranging from 200 mg·L-1 to 400 mg·L-1 did not have significant effects on S.quadricauda growth.The exposure to oxybenzone at higher concentrations also led to changes in cell structure after 96 h.Generally,protein and carbohydrate content of all microalgae except S.quadricauda increased with increasing oxybenzone concentrations.Protein content increased significantly when cells were exposed to oxybenzone,though effects were greater in the polar species,suggesting that it could be one of the adaptive strategies that enabled these microalgae to tolerate oxybenzone.Further investigation is required to determine the effects of oxybenzone on other features of microalgal performance at relevant environmental concentrations. 展开更多
关键词 polar algae temperate algae CHLORELLA benzophenone-3 emerging contaminants
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Effects of elevated temperatures on growth and photosynthetic performance of polar Chlorella 认领
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作者 Syazana ANUWAR Ming-Li TEOH +2 位作者 Wei-Hsum YAP Fong-Lee NG Siew-Moi PHANG 《极地科学进展:英文版》 CSCD 2020年第2期124-131,共8页
Global warming has been the subject of concern in today’s world with elevating temperature causing the melting of polar ice and increasing sea level.The aim of this study was to investigate the physiological and phot... Global warming has been the subject of concern in today’s world with elevating temperature causing the melting of polar ice and increasing sea level.The aim of this study was to investigate the physiological and photosynthetic performance of two polar Chlorella,namely Chlorella UMACC 250 and Chlorella UMACC 234 to elevating temperatures as might be experienced under future warming scenarios.The cultures were exposed to three different temperatures of 4℃,8℃and 12℃.The growth and photosynthetic activity were determined every 2 d for a period of 10 d.At the end of the experiment,the cultures were harvested and analysed for biochemical composition.Both Chlorella strains were able to tolerate higher temperatures than their ambient temperature.The final pigments content showed an increasing trend with increased temperatures for both strains.The photosynthetic activities were measured using pulse-amplitude modulation(PAM)fluorometer.The photosynthetic parameters including maximum quantum efficiency(Fv/Fm),maximum relative electron transport rate(r ETRmax),light harvesting efficiency(a)and photoadaptive index(Ek)were derived from the rapid light curves(RLCs).Both Chlorella strains showed a slight decline in growth and photosynthetic activities at the initial part of the experiment.However,they showed the ability to recuperate with Chlorella UMACC 250 recovers better compared to Chlorella UMACC 234.Both Chlorella strains showed similar trend in their carbohydrate content at 12℃,while the protein content of Chlorella UMACC 234 decreased when exposed to increasing temperatures.The results indicated that polar Chlorella are able to survive at increased temperatures throughout the experiment. 展开更多
关键词 POLAR CHLORELLA PHOTOSYNTHESIS pulse-amplitude modulation(PAM)fluorometry
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BDS-3新卫星对极地地区定位性能的影响分析 认领
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作者 张辉 张琦 《地理信息世界》 2020年第3期126-130,共5页
针对BDS-3新卫星对极地地区定位性能的影响,分析了BDS-3新卫星对极地地区北斗B1I、B2I以及B3I卫星3个频率数据质量以及定位精度的影响。经研究发现,BDS-3新卫星增加了极地地区北斗卫星可见数,有效改善了极地地区的北斗卫星空间分布结构... 针对BDS-3新卫星对极地地区定位性能的影响,分析了BDS-3新卫星对极地地区北斗B1I、B2I以及B3I卫星3个频率数据质量以及定位精度的影响。经研究发现,BDS-3新卫星增加了极地地区北斗卫星可见数,有效改善了极地地区的北斗卫星空间分布结构,增强了卫星信号强度,降低了多路径效应,BDS-3卫星的加入使极地地区北斗伪距单点定位精度与GPS相当。进行北斗与GPS组合精密单点定位时,BDS-3新卫星提升精度效果优于BDS-2卫星,而BDS-2/BDS-3组合精密单点定位精度低于GPS。研究结果旨在为今后极地地区北斗高精度定位研究提供一定的参考意义。 展开更多
关键词 极地 BDS-3 数据质量 定位精度
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Polar Glacial Fluctuation Is an important Factor of Global Climate Change 认领
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作者 Cuixiang Zhong 《环境科学与工程:A》 2020年第5期163-169,共7页
Global climate change has attracted more and more attention from all over the world,and how to cope with global climate change has aroused wide debate and research.Although many people believe that global warming is c... Global climate change has attracted more and more attention from all over the world,and how to cope with global climate change has aroused wide debate and research.Although many people believe that global warming is caused by releasing too much greenhouse gas,there are still controversies in the scientific community.Thus,the author has analyzed various factors affecting global climate change to find that polar glacial fluctuation affects the activities of polar vortices and that the activities of the Moon and polar vortices directly cause global climate change,therefore can conclude that the change of polar glaciers is the main factor affecting the global climate change and put forward corresponding countermeasures to prevent global climate change. 展开更多
关键词 Polar vortex MOON global climate change CAUSE COUNTERMEASURE
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Application of Polar Code-Based Scheme in Cloud Secure Storage 认领
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作者 Zhe Li Yiliang Han Yu Li 《国际计算机前沿大会会议论文集》 2020年第1期676-689,共14页
In view of the fact that the quantum computer attack is not considered in the cloud storage environment,this paper selects the code-based public key encryption scheme as the security protection measure in the cloud st... In view of the fact that the quantum computer attack is not considered in the cloud storage environment,this paper selects the code-based public key encryption scheme as the security protection measure in the cloud storage.Based on random linear code encryption scheme,it employs the structure of the RLCE scheme and Polar code polarization properties,using the Polar code as underlying encoding scheme,through the method of RLCEspad,putting forward a kind of improved public key encryption scheme which considers semantic security and is resistant to adaptively chosen ciphertext attacks.The improved scheme is applied to cloud storage to ensure that the storage environment will not be attacked by quantum computer while ensuring the confidentiality,availability and reliability. 展开更多
关键词 Post-quantum cryptography Polar code Random linear code encryption Code-based scheme Cloud storage
Non-spherical aluminum nanoparticles fabricated using picosecond laser ablation 认领
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作者 A.Brahma Swamulu S.Venugopal Rao G.Krishna Podagatlapalli 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2020年第7期980-986,共7页
We report the picosecond laser ablation of aluminum targets immersed in a polar organic liquid(chloroform,CHCl3)with~2 ps laser pulses at an input energy of~350μJ.The synthesized aluminum nanoparticles exhibited a su... We report the picosecond laser ablation of aluminum targets immersed in a polar organic liquid(chloroform,CHCl3)with~2 ps laser pulses at an input energy of~350μJ.The synthesized aluminum nanoparticles exhibited a surface plasmon resonance peak at~340 nm.Scanning electron microscopy images of Al nanoparticles demonstrated the spherical morphology with an average size of(27±3.6)nm.The formation of smaller spherical Al nanoparticles and the diminished growth could be from the formation of electric double layers on the Al nanoparticles.In addition to spherical aluminum nanoparticles,triangular/pentagonal/hexagonal nanoparticles were also observed in the colloidal solution.Field emission scanning electron microscopy images of ablated Al targets demonstrated laser induced periodic surface structures(LIPSSs),which were the high spatial frequency LIPSSs(HSF-LIPSSs)since their grating period was~280 nm.Additionally,coarse structures with a period of~700 nm were observed. 展开更多
关键词 ablation PICOSECOND SILVER POLAR periodic surfaces electric double layers
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Three-dimensionally interconnected Co9S8/MWCNTs composite cathode host for lithium–sulfur batteries 认领 被引量:1
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作者 Shengyu Zhao Xiaohui Tian +2 位作者 Yingke Zhou Ben Ma Angulakshmi Natarajan 《能源化学:英文版》 SCIE EI CAS CSCD 2020年第7期22-29,I0002,共9页
Several challenging issues,such as the poor conductivity of sulfur,shuttle effects,large volume change of cathode,and the dendritic lithium in anode,have led to the low utilization of sulfur and hampered the commercia... Several challenging issues,such as the poor conductivity of sulfur,shuttle effects,large volume change of cathode,and the dendritic lithium in anode,have led to the low utilization of sulfur and hampered the commercialization of lithium–sulfur batteries.In this study,a novel three-dimensionally interconnected network structure comprising Co9 S8 and multiwalled carbon nanotubes(MWCNTs)was synthesized by a solvothermal route and used as the sulfur host.The assembled batteries delivered a specific capacity of1154 m Ah g-1 at 0.1 C,and the retention was 64%after 400 cycles at 0.5 C.The polar and catalytic Co9 S8 nanoparticles have a strong adsorbent effect for polysulfide,which can effectively reduce the shuttling effect.Meanwhile,the three-dimensionally interconnected CNT networks improve the overall conductivity and increase the contact with the electrolyte,thus enhancing the transport of electrons and Li ions.Polysulfide adsorption is greatly increased with the synergistic effect of polar Co9 S8 and MWCNTs in the three-dimensionally interconnected composites,which contributes to their promising performance for the lithium–sulfur batteries. 展开更多
关键词 Three-dimensional network structure MWCNTS Polar and catalytic Co9S8 Lithium–sulfur batteries
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