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扫描电镜能谱与冷冻传输装置联用测试矿物中流体包裹体固液相成分的方法研究 被引量:1
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作者 杨德平 舒磊 +3 位作者 熊玉新 王旭 刘鹏瑞 刘智 《岩矿测试》 CAS CSCD 北大核心 2015年第5期550-557,共8页
研究流体包裹体中子矿物种类、化学成分及分布特征,对于确定热液成分和成矿物理化学条件、流体的演化规律和成矿机制等有非常重要的意义。但目前常用的各种测试研究方法存在测试目的物寻找困难、不透明子矿物难鉴定等局限性。本文采用... 研究流体包裹体中子矿物种类、化学成分及分布特征,对于确定热液成分和成矿物理化学条件、流体的演化规律和成矿机制等有非常重要的意义。但目前常用的各种测试研究方法存在测试目的物寻找困难、不透明子矿物难鉴定等局限性。本文采用冷冻传输装置首先将流体包裹体冷冻固定并打开,然后用扫描电镜、能谱仪测试矿物中流体包裹体中的子矿物和液相成分,该方法可解决扫描电镜下流体包裹体研究目标物不易寻找,打开流体包裹体后子矿物易散失和碎屑易混入的问题,可有效测试小颗粒(1~2μm)、不透明子矿物及不透明矿物中的流体包裹体固液相成分。用该方法实测山东邹平王家庄铜矿流体包裹体液相中Na+、K+、Cl-组分的质量分数分别为5.85%、3.60%、16.18%,计算的盐度为35.35%,并确定了其中不透明矿物子矿物为黄铜矿,证明了黄铜矿是从高盐度热液中晶出的结论。本方法为矿物中流体包裹体研究提供了一种新的测试手段。 展开更多
关键词 流体包裹体 固液相成分 冷冻传输装置 扫描电镜 能谱仪
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原位电子显微学数码相机的研发(英文)
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作者 潘明 《电子显微学报》 CAS CSCD 北大核心 2010年第3期295-310,共16页
本文首先简单回顾了原位电子显微学的发展历史。电子显微镜的不断更新换代和其他新配件的出现对原位电子显微学的发展起了很大的作用。其中记录和采集图像使用的相机尤为重要。本文重点讨论了原位电子显微学数码相机设计的主要参数(运... 本文首先简单回顾了原位电子显微学的发展历史。电子显微镜的不断更新换代和其他新配件的出现对原位电子显微学的发展起了很大的作用。其中记录和采集图像使用的相机尤为重要。本文重点讨论了原位电子显微学数码相机设计的主要参数(运行速度,分辨率,和灵敏度).并给出两例使用新一代数码相机的原位电子显微学应用实例。最后展望未来原位电子显微学的发展方向和新的需求。 展开更多
关键词 CCD数码相机 CMOS数码探测器 原位电子显微学 TV相机 图像增强器 实时观测 视频图像 单幅视频 运行速度 噪音 分辨率 灵敏度 使用周期 MTF DQE 数字视频流 硅纳米线
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Speed profile optimization of catenary-free electric trains with lithium-ion batteries
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作者 Nima Ghaviha Markus Bohlin +1 位作者 Christer Holmberg Erik Dahlquist 《Journal of Modern Transportation》 2019年第3期153-168,共16页
Catenary-free operated electric trains, as one of the recent technologies in railway transportation, has opened a new field of research: speed profile optimization and energy optimal operation of catenary-free operate... Catenary-free operated electric trains, as one of the recent technologies in railway transportation, has opened a new field of research: speed profile optimization and energy optimal operation of catenary-free operated electric trains. A well-formulated solution for this problem should consider the characteristics of the energy storage device using validated models and methods. This paper discusses the consideration of the lithium-ion battery behavior in the problem of speed profile optimization of catenary-free operated electric trains. We combine the single mass point train model with an electrical battery model and apply a dynamic programming approach to minimize the charge taken from the battery during the catenary-free operation. The models and the method are validated and evaluated against experimental data gathered from the test runs of an actual battery-driven train tested in Essex, UK. The results show a significant potential in energy saving. Moreover, we show that the optimum speed profiles generated using our approach consume less charge from the battery compared to the previous approaches. 展开更多
关键词 ELECTRIC TRAIN Catenary-free operation Speed profile OPTIMIZATION Energy efficiency
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Windows 10’s Browser Forensic Analysis for Tracing P2P Networks’Anonymous Attacks
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作者 Saima Kauser Tauqeer Safdar Malik +2 位作者 Mohd Hilmi Hasan Emelia Akashah P.Akhir Syed Muhammad Husnain Kazmi 《Computers, Materials & Continua》 SCIE EI 2022年第7期1251-1273,共23页
A web browser is the most basic tool for accessing the internet from any of the machines/equipment.Recently,data breaches have been reported frequently from users who are concerned about their personal information,as ... A web browser is the most basic tool for accessing the internet from any of the machines/equipment.Recently,data breaches have been reported frequently from users who are concerned about their personal information,as well as threats from criminal actors.Giving loss of data and information to an innocent user comes under the jurisdiction of cyber-attack.These kinds of cyber-attacks are far more dangerous when it comes to the many types of devices employed in an internet of things(IoT)environment.Continuous surveillance of IoT devices and forensic tools are required to overcome the issues pertaining to secure data and assets.Peer to peer(P2P)applications have been utilized for criminal operations on the web.Therefore,it is a challenge for a forensic investigator to perform forensic analysis of the evolving hardware and software platforms for IoT.For identity concealment and privacy protection,the Onion Router(Tor)and Chrome with the Invisible Internet Project(I2P)as the foundation browser are often used.Confirmation is required to determine whether Tor is truly anonymous and private as they claim.Some people,on the other hand,utilize the Tor browser for evil reasons.Tools and techniques are available for the collection of artifacts,identifying problem areas,further processing and analysis of data on the computer and IoT.Present research tried to explore a few tools for the tracing of I2P activities over computer on windows 10 that reflects IoT devices.According to the results of this research,it leaves an excessive amount of important digital evidence on the operating system that can be exploited to attack the information of users.This research is based on windows operating system and does not support other operating systems. 展开更多
关键词 Cyber-security peer-to-peer invisible internet project(I2P) forensic analysis the onion router(Tor)
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染色体5q31-32与银屑病相关性分析:易感位点确定但与SLC22A4和SLC22A5的单核苷酸多态性无关
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作者 Friberg C. Bjrck K. +1 位作者 Nilsson S. 董平 《世界核心医学期刊文摘(皮肤病学分册)》 2006年第9期16-16,共1页
We have previously reported a region on chromosome 5q as a possible susceptibility region for psoriasis. This cytokine cluster-rich region has also been suggested as a susceptibility locus in other autoimmune or infla... We have previously reported a region on chromosome 5q as a possible susceptibility region for psoriasis. This cytokine cluster-rich region has also been suggested as a susceptibility locus in other autoimmune or inflammatory diseases including Crohn’ s disease (CD) and rheumatoid arthritis (RA). Three specific single-nucleotide polymorphisms (SNPs) have been reported to associate with RA and CD and to change the functional activity of two organic cation transporters, solute carrier family 22 member 4/5 (SLC22A4) and (SLC22A5). In this study, we have analyzed these SNPs for an association with psoriasis. We have also performed a denser linkage analysis of this region with an additional 31 microsatellite markers. We were not able to detect any association with any of the three SNPs analyzed. However, our linkage result supports the involvement of this region in the etiology of psoriasis. We obtained a peak non-parametric linkage value of 3.1 for marker D5S436 in a subgroup of patients with joint complaints. This result supports the findings in another study of psoriasis patients originating from Iceland in which the authors obtained a peak logarithm of the odds score of 2.6 for marker D5S2090, only 2 Mb from D5S436. This suggests a psoriasis susceptibility locus on chromosome 5q32 that is involved in the arthritic phenotype of the disease. 展开更多
关键词 单核苷酸多态性 关节型银屑病 染色体5q 易感位点 关性分析 类风湿性关节炎 自身免疫性疾病 连锁分析
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瑞典六年级和九年级学生与其所经历的压力有关的考试成绩及自尊心——唾液中氢化可的松水平和针对压力的心理反应
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作者 Lindahl M. Theorell T. +1 位作者 Lindblad F. 朱新菊 《世界核心医学期刊文摘(儿科学分册)》 2006年第A03期17-18,共2页
Aims: To study relations between test performance, academic self-esteem, self-reported stress and saliva cortisol levels in students exposed to test demands at school. Methods: 46 randomly selected 6th and 9th graders... Aims: To study relations between test performance, academic self-esteem, self-reported stress and saliva cortisol levels in students exposed to test demands at school. Methods: 46 randomly selected 6th and 9th graders voluntarily participated in an experimental school test concerning reading and mathematics skills. Cortisol saliva samples were collected at awakening, 30 min later, before test and after test. Perceived stress was registered with a visual analogue scale (VAS). A standardized self-rating questionnaire for measuring self-esteem was administered together with questions about school stress and psychological reactions when exposed to stress during a test. Results: Experienced stress during the school test was correlated to low test performance and to low self-rated evaluation of self-esteem as well as to an increase of saliva cortisol levels during the test. There were also correlations between certain psychological reactions to demands and different cortisol measures. Children who reported that they applied the procedure “ I say to myself: I can solve this task” in a school test situation had a lower morning increase of saliva cortisol. Reported use of the procedure “ I get worried and will have problems solving other tasks too” -when referring to a school test situation -was correlated to an increase in cortisol levels during the test situation. Conclusion: Test performance, academic self-esteem, perceived stress and reactions of the hypothalamus-pituitary-adrenal axis (HPA axis) are highly intertwined. Furthermore, certain school stress psychological reactions to performance demands seem to be related to different cortisol reactions. 展开更多
关键词 心理压力 心理反应 自我评定 自我评价 应激心理 自我报告 数学技能
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Catquest-9SF functioning over a decade–a study from the Swedish National Cataract Register 被引量:1
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作者 Mats Lundström Maria Kugelberg +4 位作者 Per Montan Ingela Nilsson Madeleine Zetterberg Konrad Pesudovs Anders Behndig 《Eye and Vision》 SCIE CSCD 2020年第1期553-562,共10页
Background:The Swedish National Cataract Register(NCR)collects data on cataract surgery outcomes during March,including patient-reported outcomes using the Catquest-9SF questionnaire for over 11 years.Previous studies... Background:The Swedish National Cataract Register(NCR)collects data on cataract surgery outcomes during March,including patient-reported outcomes using the Catquest-9SF questionnaire for over 11 years.Previous studies from NCR have shown that the preoperative visual acuity has improved over time.The main purpose of this study was to evaluate the Catquest-9SF Rasch scoring performance in this changing environment.A second purpose was to describe clinical data over the same period for those who completed the questionnaire.Methods:The performance of the Catquest-9SF was analysed by a separate Rasch analysis for each year,resulting in a preoperative and postoperative score for each participating patient in the annual cohorts.The clinical data and questionnaire scoring were analysed for each year in the period 2008-2018 inclusive.Results:Data were available for 42,023 eyes for 11 annual cohorts(2008-2018).The psychometric properties of the questionnaire were stable during the study period.Person separation(precision)for the whole period was 2.58 and varied between 2.45 and 2.72.The person reliability was 0.87 and varied between 0.86 and 0.88.The targeting of question difficulty to person ability became less accurate over time meaning that the item activities became easier to carry out without difficulty.The average targeting for the whole period was−2.06 and changed from−1.92 in 2008 to−2.31 in 2018.The person score improved both before surgery and after surgery,indicating that patients are undergoing surgery at a more able level and getting better outcomes.The average improvement by surgery decreased from 3.41 logits in 2008 to 3.21 logits in 2018(p=0.003).Over time,patient age decreased from 75 to 74 years(p<0.001)and the proportion of women decreased from 63.9 to 57.9%(p<0.001).The mean preoperative visual acuity in both the operated eye and the better eye improved over time(0.47 to 0.40 logMAR,p<0.001 and 0.22 to 0.19 logMAR,p<0.001,respectively),as did the mean postoperative visual acuity in the operated eye(0.14 to 0.09 logMAR,p<0.001).Conclusions:The Catquest-9SF retained stable psychometric properties over this 11-year period although more recent cohorts included slightly younger patients with somewhat better vision. 展开更多
关键词 Cataract extraction OUTCOMES QUESTIONNAIRE Patient-reported outcomes Rasch analysis
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A data-driven approach for predicting long-term degradation of a fleet of micro gas turbines 被引量:1
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作者 Tomas Olsson Enislay Ramentol +2 位作者 Moksadur Rahman Mark Oostveen Konstantinos Kyprianidis 《Energy and AI》 2021年第2期30-44,共15页
Predictive health monitoring of micro gas turbines can significantly increase the availability and reduce the operating and maintenance costs.Methods for predictive health monitoring are typically developed for large-... Predictive health monitoring of micro gas turbines can significantly increase the availability and reduce the operating and maintenance costs.Methods for predictive health monitoring are typically developed for large-scale gas turbines and have often focused on single systems.In an effort to enable fleet-level health monitoring of micro gas turbines,this work presents a novel data-driven approach for predicting system degradation over time.The approach utilises operational data from real installations and is not dependent on data from a reference system.The problem was solved in two steps by:1)estimating the degradation from time-dependent variables and 2)forecasting into the future using only running hours.Linear regression technique is employed both for the estimation and forecasting of degradation.The method was evaluated on five different systems and it is shown that the result is consistent(r>0.8)with an existing method that computes corrected values based on data from a reference system,and the forecasting had a similar performance as the estimation model using only running hours as an input. 展开更多
关键词 Fleet monitoring Micro gas turbine Machine learning Health monitoring Predictive maintenance Power generation
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Vacancy Ordering and Lithium Insertion inⅢ_(2)Ⅵ_(3) Nanowires
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作者 Hailin Peng Xiao Feng Zhang +1 位作者 Ray DTwesten Yi Cui 《Nano Research》 SCIE EI CSCD 2009年第4期327-335,共9页
Superlattice structures resulting from vacancy ordering have been observed in many materials.Here we report vacancy ordering behavior inⅢ_(2)Ⅵ_(3)nanowires.The formation of layer-like structural vacancies has been a... Superlattice structures resulting from vacancy ordering have been observed in many materials.Here we report vacancy ordering behavior inⅢ_(2)Ⅵ_(3)nanowires.The formation of layer-like structural vacancies has been achieved during the synthesis of In_(2)Se_(3)nanowires through a vapor-transport route.Doping In_(2)Se_(3)nanowires with small amounts of Ga during synthesis can completely change the structural vacancy ordering from a layer-like to a screw-like pattern for(In_(x)Ga_(1-x))_(2)Se_(3)nanowires.Lithium atoms can fill in the layer-like structural vacancies of In_(2)Se_(3)nanowires and generate new types of vacancy and lithium atom ordering superlattices.The screw-patterned vacancies of(In_(x)Ga_(1-x))_(2)Se_(3)nanowires show reversible lithium insertion.Our results contribute to the understanding of structure property correlations ofⅢ_(2)Ⅵ_(3)materials used in lithium ion storage,photovoltaics,and phase change memory. 展开更多
关键词 Nanowire(NW) vacancy ordering SUPERLATTICE Ⅲ-Ⅵ lithium insertion
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