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GCS型低压抽出式开关柜专用的限流电抗器简介
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作者 李德隆 顾建刚 《江苏电器》 1997年第3期29-30,共2页
为提高低压开关柜的可靠性,专门设计了一种低压限流电抗器,介绍了这种电抗器的结构,参数及使用效果。
关键词 开关柜 限流电抗器 设计 可靠性
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湖相碎屑岩高频层序地层新认识:来自古代沉积层序的启示
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作者 ZAVALA Carlos 刘化清 +5 位作者 李相博 杨占龙 李阳 王菁 TROBBIANI Valentin ARCURI Mariano 《岩性油气藏》 北大核心 2026年第1期38-54,共17页
层序地层学理论和方法为地层分析提供了新工具,有助于深化对沉积模式和盆地演化的理解。传统的层序地层学理论中,沉积单元与部分名词术语(如层序界面、体系域、准层序等)是主要针对海相沉积系统提出的,而湖相沉积系统因受构造运动与高... 层序地层学理论和方法为地层分析提供了新工具,有助于深化对沉积模式和盆地演化的理解。传统的层序地层学理论中,沉积单元与部分名词术语(如层序界面、体系域、准层序等)是主要针对海相沉积系统提出的,而湖相沉积系统因受构造运动与高频气候旋回的复合控制,非海平面变化驱动,其层序地层特征的复杂程度远高于海相沉积系统。通过对不同湖盆类型的沉积体系的系统解剖,厘清了湖相沉积层序地层学的相关概念,并探讨了他旋回对湖相沉积和层序地层的控制作用以及湖盆可容纳空间类型及其对层序地层和油气成因的意义。研究结果表明:(1)湖泊沉积状态可划分为3种类型,即欠填充、平衡填充和过填充湖泊,不同状态下湖泊的水体盐度、沉积层序、体系域等具有显著差别。在欠填充时期,湖泊水体是完全封闭的,受高频干湿气候循环影响,湖平面波动变化较大,在潮湿期,河流可提供大量水和沉积物,湖平面上升形成湖侵域(TST),发育向上变细变薄的沉积层序单元(EDS);在干旱期,湖平面下降,湖盆边缘区域暴露,形成湖退域(RST),湖水盐度为微咸水—超咸水。在平衡填充时期,湖泊呈半封闭状态,兼具欠填充和过填充双重特征,在TST发育期,湖泊呈欠填充状态,随着河流水和沉积物的持续供给,形成向上变细的沉积层序,直到湖平面达到最大洪泛期的溢出点;在RST发育期,湖泊呈过填充状态,发育向上变粗的前积型滨岸三角洲和水下三角洲沉积,此时湖水盐度为咸水—淡水。在过填充时期,湖泊的水体环境是开放的,即湖平面始终维持在湖泊溢出点附近,注入的多余河水会通过溢出点流出,其沉积物主要形成于RST期,表现为向上变粗的前积型滨岸沉积及水下三角洲沉积,且大多数过填充湖泊为淡水湖。(2)构造沉降作用对于湖泊沉积物的长期保存至关重要,水和沉积物可在无沉降区暂时保存,但这些沉积物难以保存在现今地层中。沉降型湖泊发育永久性可容纳空间,悬湖发育暂时性可容纳空间,虽然悬湖无法永久保存沉积物,但其临时储存的大量水体可以瞬时决口,淹没下游沉降型湖泊,这为富含有机物页岩的发育创造了有利条件。悬湖决口形成的洪水会导致下游沉降型湖泊发生大规模快速强制性湖侵(FT),从而形成了一种与正常水及沉积物供给无关的异整合面。 展开更多
关键词 湖相层序地层学 欠填充湖泊 平衡填充湖泊 过填充湖泊 强制性湖侵 强制性湖退 他旋回 可容纳空间
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A Novel Signature-Based Secure Intrusion Detection for Smart Transportation Systems
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作者 Hanaa Nafea Awais Qasim +3 位作者 Sana Abdul Sattar Adeel Munawar Muhammad Nadeem Ali Byung-Seo Kim 《Computers, Materials & Continua》 2026年第3期1309-1324,共16页
The increased connectivity and reliance on digital technologies have exposed smart transportation systems to various cyber threats,making intrusion detection a critical aspect of ensuring their secure operation.Tradit... The increased connectivity and reliance on digital technologies have exposed smart transportation systems to various cyber threats,making intrusion detection a critical aspect of ensuring their secure operation.Traditional intrusion detection systems have limitations in terms of centralized architecture,lack of transparency,and vulnerability to single points of failure.This is where the integration of blockchain technology with signature-based intrusion detection can provide a robust and decentralized solution for securing smart transportation systems.This study tackles the issue of database manipulation attacks in smart transportation networks by proposing a signaturebased intrusion detection system.The introduced signature facilitates accurate detection and systematic classification of attacks,enabling categorization according to their severity levels within the transportation infrastructure.Through comparative analysis,the research demonstrates that the blockchain-based IDS outperforms traditional approaches in terms of security,resilience,and data integrity. 展开更多
关键词 Smart transportation intrusion detection network security blockchain smart contract
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2019年度GC32世界帆船巡回赛第三站阿曼航空队夺冠
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作者 萧潇 《游艇》 2019年第5期16-21,共6页
2019年8月38,2019年度GC32世界帆船巡回赛第三站2019第三十八届西班牙国王杯帆船赛(Copa del Rey MAPFRE)结束,阿曼航空队(Oman Air)从老对手阿灵基队手中成功卫冕,赢得胜利。对于新西兰船长亚当·米诺普里奥(Adam Minoprio)及其船... 2019年8月38,2019年度GC32世界帆船巡回赛第三站2019第三十八届西班牙国王杯帆船赛(Copa del Rey MAPFRE)结束,阿曼航空队(Oman Air)从老对手阿灵基队手中成功卫冕,赢得胜利。对于新西兰船长亚当·米诺普里奥(Adam Minoprio)及其船员而言,自从2019年6月在上一站被埃内斯托·贝尔塔雷利(Ernesto Bertarelli)率领的瑞士代表队击败后,这次的胜利无疑是一次美妙的回归。 展开更多
关键词 帆船 航空 阿曼 世界 ADAM 西班牙 DEL 新西兰
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含高比例分布式光伏的主动配电网分区电压控制
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作者 张磊 王凌谊 +4 位作者 赵爽 纳智敏 张勇 刘志坚 虞忠明 《电机与控制应用》 2025年第9期1026-1038,共13页
【目的】高比例分布式光伏(DPV)接入改变了主动配电网(ADN)的运行方式,PV出力的随机性和波动性,导致配电网出现有功损耗过大、电压波动增大以及无功配置不均衡等问题。因此,本文提出了一种基于改进电气距离的网络分区电压控制方法,旨在... 【目的】高比例分布式光伏(DPV)接入改变了主动配电网(ADN)的运行方式,PV出力的随机性和波动性,导致配电网出现有功损耗过大、电压波动增大以及无功配置不均衡等问题。因此,本文提出了一种基于改进电气距离的网络分区电压控制方法,旨在实现含高比例DPV的ADN的分区电压控制。【方法】鉴于集中式电压优化模型在高比例DPV场景下决策变量与约束条件规模庞大、计算复杂度过高,本文首先提出基于改进电气距离的网络分区方法,将ADN划分为多个可控子区域以降低求解规模;其次,针对分区中相邻子区域边界节点的电压协调问题,设计了一种分布式电压控制策略;最后,采用基于黏菌算法的分布式求解方法实现该策略的高效求解。【结果】利用IEEE 33节点模型和云南曲靖的199节点真实系统进行仿真验证。结果表明,所提基于分区的分布式电压控制优化方法不仅能有效维持系统电压水平,其分布式求解效率也显著优于集中式优化方法。【结论】所提方法成功实现了各子区域电压的协同控制,有效维持了系统电压水平。 展开更多
关键词 分布式光伏 主动配电网 网络分区 黏菌算法 电压控制
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Co-existence of compressive and rarefactive dust acoustic solitary structures in Saturn’s rings with non-Maxwellian ions and electrons
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作者 S A M Zaidi M N S Qureshi Saba Khalid 《Communications in Theoretical Physics》 2025年第5期184-197,共14页
In the present study,we investigated the existence of arbitrary amplitude dust acoustic solitons by considering the Cairns distributed ions,negatively charged streaming dust grains along with(r,q)distributed electrons... In the present study,we investigated the existence of arbitrary amplitude dust acoustic solitons by considering the Cairns distributed ions,negatively charged streaming dust grains along with(r,q)distributed electrons in an un-magnetized dusty plasma.We used the pseudopotential technique to obtain the solitary wave solution.It is seen that the coexistence of rarefactive and compressive solitons is possible when ions and electrons are nonthermally distributed.We found that the soliton characteristics are strongly dependent on the choice of velocity distribution function through the nonthermal spectral indices r q,,a as well as on the ion and dust temperatures.For(r,q)distributed electrons,we found that the soliton amplitude increases(decreases)with smaller(higher)values of negative(positive)r.For Cairns distributed ions,we found a transition from negative to positive polarity solitary structures with the coexistence in between as the nonthermal parameter a increases.Our results gave a better explanation for the formation of dust acoustic solitary structures and their dependence on high and low energy particles in nonthermal distribution profiles in space environments. 展开更多
关键词 dusty plasmas generalized(r q)distribution non-Maxwellian distribution dust acoustic waves compressive and rarefactive solitons
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First-order correction of tunneling and entropy in the Horndeski gravity-like hairy black hole
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作者 Riasat Ali Xia Tiecheng Rimsha Babar 《Communications in Theoretical Physics》 2025年第7期142-152,共11页
In this work,we apply tunneling formalism to analyze charged particles tunneling across a hairy black hole horizon.Such black hole solutions are essential for frameworks based on Horndeski's gravity theory.Applyin... In this work,we apply tunneling formalism to analyze charged particles tunneling across a hairy black hole horizon.Such black hole solutions are essential for frameworks based on Horndeski's gravity theory.Applying a semi-classical technique,we examine the tunneling of charged particles from a hairy black hole and derive the generic tunneling spectrum of released particles,ignoring self-gravitational and interaction.It is studied to ignore the back-reaction impact of the radiated particle on the hairy black hole.We analyze the properties of the black hole,such as temperature and entropy,under the influence of quantum gravity and also observe that the firstorder correction is present.We study tunneling radiation produced by a charged field equation in the presence of a generalized uncertainty effect.We modify the semi-classical technique by using the generalized uncertainty principle,the WKB approximation,and surface gravity. 展开更多
关键词 Horndeski like hairy black hole hawking temperature semi-classical approach quantum correction corrected entropy
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GWO-LightGBM:A Hybrid Grey Wolf Optimized Light Gradient Boosting Model for Cyber-Physical System Security
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作者 Adeel Munawar Muhammad Nadeem Ali +1 位作者 Awais Qasim Byung-Seo Kim 《Computer Modeling in Engineering & Sciences》 2025年第10期1189-1211,共23页
Cyber-physical systems(CPS)represent a sophisticated integration of computational and physical components that power critical applications such as smart manufacturing,healthcare,and autonomous infrastructure.However,t... Cyber-physical systems(CPS)represent a sophisticated integration of computational and physical components that power critical applications such as smart manufacturing,healthcare,and autonomous infrastructure.However,their extensive reliance on internet connectivity makes them increasingly susceptible to cyber threats,potentially leading to operational failures and data breaches.Furthermore,CPS faces significant threats related to unauthorized access,improper management,and tampering of the content it generates.In this paper,we propose an intrusion detection system(IDS)optimized for CPS environments using a hybrid approach by combining a natureinspired feature selection scheme,such as Grey Wolf Optimization(GWO),in connection with the emerging Light Gradient Boosting Machine(LightGBM)classifier,named as GWO-LightGBM.While gradient boosting methods have been explored in prior IDS research,our novelty lies in proposing a hybrid approach targeting CPS-specific operational constraints,such as low-latency response and accurate detection of rare and critical attack types.We evaluate GWO-LightGBM against GWO-XGBoost,GWO-CatBoost,and an artificial neural network(ANN)baseline using the NSL-KDD and CIC-IDS-2017 benchmark datasets.The proposed models are assessed across multiple metrics,including accuracy,precision,recall,and F1-score,with an emphasis on class-wise performance and training efficiency.The proposed GWO-LightGBM model achieves the highest overall accuracy(99.73%)for NSL-KDD and(99.61%)for CIC-IDS-2017,demonstrating superior performance in detecting minority classes such as Remote-to-Local(R2L)and Other attacks—commonly overlooked by other classifiers.Moreover,the proposed model consumes lower training time,highlighting its practical feasibility and scalability for real-time CPS deployment. 展开更多
关键词 Cyber-physical systems intrusion detection system machine learning digital contents copyright protection grey wolf optimization gradient boosting network security content protection LightGBM
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一个由干湿交替极端气候事件主导的内陆湖盆:来自鄂尔多斯盆地上三叠统延长组露头剖面的沉积学证据 被引量:12
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作者 李相博 刘化清 +7 位作者 杨伟伟 张艳 Carlos Zavala 吉利民 杨占龙 郝彬 黄军平 王菁 《地球科学》 EI CAS CSCD 北大核心 2023年第1期293-316,共24页
鄂尔多斯盆地是我国陆上最主要的油气盆地之一,三叠系延长组是该盆地的主要含油层位.通过对延长组典型露头的考察与研究,结合古生物及岩性岩相资料,取得了3点新认识:(1)恢复了延长组沉积时期的古气候环境,认为其具有三分性,其中早期拉... 鄂尔多斯盆地是我国陆上最主要的油气盆地之一,三叠系延长组是该盆地的主要含油层位.通过对延长组典型露头的考察与研究,结合古生物及岩性岩相资料,取得了3点新认识:(1)恢复了延长组沉积时期的古气候环境,认为其具有三分性,其中早期拉丁期为干旱环境;中期受卡尼期梅雨事件(CPE)影响气候发生突变,转变为温暖潮湿气候环境;晚期诺利-瑞替期再次转变为半干旱-半湿润气候环境.(2)CPE事件改变了延长组沉积物搬运与沉积方式,其中CPE事件之前与事件之后的干旱环境时期,主要发育暴雨洪水引发的季节性河流、决口扇、决口河道沉积;CPE事件当中及卡尼中期,陆源碎屑物质主要通过异重流、浊流及砂质碎屑流等多种途径搬运至水下环境,形成富砂质重力流事件沉积,同时受CPE事件控制,在深水环境还发育了黑色富有机质页岩事件沉积.(3)建立了延长组干旱与潮湿两种环境沉积模式,干旱环境湖泊水域面积较小,主要沉积单元为洪泛平原、季节性河道及决口扇,主要沉积方式为填平补齐、加积式沉积,不发育前积沉积现象;潮湿环境湖泊水域面积较大,发育完整的陆相河流-三角洲-湖泊-重力流沉积体系,由于具有稳定的长流水,河道相对固定,加之受湖平面变化控制,其沉积方式以前积作用为主.该认识不仅对于深入探讨鄂尔多斯延长组大型坳陷湖盆形成演化机理、沉积层序充填演化及指导油气勘探实践有积极意义,而且对揭示晚三叠世全球极端气候事件在内陆湖盆的沉积学记录有积极意义,可以填补CPE事件在古特提斯东缘泛大陆内部沉积响应研究的空白. 展开更多
关键词 干湿气候交替 洪水事件 梅雨事件 沉积模式 延长组 晚三叠世 鄂尔多斯盆地 石油地质学
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一种红外与可见光融合的“双双目”立体视觉系统的标定方法研究 被引量:7
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作者 赵美蓉 李瀚辰 佟颖 《光学技术》 CAS CSCD 北大核心 2017年第5期385-393,共9页
针对红外相机与可见光相机联合标定的问题,利用不同物体红外辐出度的差异,设计了可同时应用于红外相机与可见光相机标定的平面靶标。利用"最大稳定极值区域"(MSER)算法,检测靶标的镂空深色区域。为克服图像可能存在较大畸变... 针对红外相机与可见光相机联合标定的问题,利用不同物体红外辐出度的差异,设计了可同时应用于红外相机与可见光相机标定的平面靶标。利用"最大稳定极值区域"(MSER)算法,检测靶标的镂空深色区域。为克服图像可能存在较大畸变的问题,通过相邻最大稳定极值区域质心的位置关系预估角点所在位置,在预估位置内进行角点检测,提取用于标定的亚像素角点位置。结果表明:新型靶标及相应的角点提取方法能够同时满足于红外相机与可见光相机内外参数标定的需要。通过红外与可见光"双双目"立体视觉系统的融合重构效果可看出,提供的标定数据能够满足系统需求。 展开更多
关键词 几何光学 相机标定 红外相机标定 最大稳定极值区域 “双双目”视觉系统
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传感器驱动的智能选矿:过去、现在和未来 被引量:13
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作者 吴西顺 邓杰 +4 位作者 姜焕琴 姚翔 张炜 田黔宁 《矿产综合利用》 CAS 北大核心 2020年第5期18-26,共9页
基于传感器、大数据、AI的智能选矿,是建设现代智慧矿山的重要组成部分。传感器驱动的智能选矿,本质是数据驱动。选矿的自动化起步较早,但智能化滞后于其他行业,主要原因在于对传感器重视不够。几十年的矿业应用经验和发展趋势显示其自... 基于传感器、大数据、AI的智能选矿,是建设现代智慧矿山的重要组成部分。传感器驱动的智能选矿,本质是数据驱动。选矿的自动化起步较早,但智能化滞后于其他行业,主要原因在于对传感器重视不够。几十年的矿业应用经验和发展趋势显示其自动化程度不断提高,光选正在逐渐汇集成一大类智能感知与识别技术。颠覆性技术创新正重塑矿业新流程;高通量颗粒分拣从XRF、激光、近红外、色彩和XRT等多样化光源发展汲取能量;中子激活分析(PGNAA)、磁共振(MR)等传感技术的进步开创使块状拣选成为一项新兴领域;先进过程控制等数字化管理技术在研磨和浮选领域大显身手;CPR回收推动下游尾矿管理创新及综合利用从而实现可持续性发展。行业实践上,国际灯塔项目为智能选矿的发展提供了实际案例及宝贵经验。 展开更多
关键词 智能选矿 传感器 块状拣选 颗粒分选 颠覆性创新
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九里香叶对去卵巢大鼠体积骨密度、血钙、血磷、碱性磷酸酶、骨组织形态学的影响 被引量:2
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作者 文娱 李晓晖 +4 位作者 尤文质 郑启忠 高海 张秋萍 彭清华 《世界中医药》 CAS 2017年第10期2427-2430,共4页
目的:观察九里香叶对去卵巢大鼠体积骨密度、血钙、血磷、碱性磷酸酶、骨组织形态学的影响。方法:取60只SPF级SD雌性大鼠,通过切除双侧卵巢复制骨质疏松模型。术后7 d分组给药。模型组:生理盐水(0.4 mg/kg·d);对照组:生理盐水(0.4 ... 目的:观察九里香叶对去卵巢大鼠体积骨密度、血钙、血磷、碱性磷酸酶、骨组织形态学的影响。方法:取60只SPF级SD雌性大鼠,通过切除双侧卵巢复制骨质疏松模型。术后7 d分组给药。模型组:生理盐水(0.4 mg/kg·d);对照组:生理盐水(0.4 mg/kg·d);戊酸雌二醇组:0.4 m g/kg·d;九里香高剂量组:200 mg/kg·d;九里香中剂量组:100 mg/kg·d;九里香低剂量组:50 mg/kg·d。连续给药90 d。给药结束后,测定大鼠体积骨密度,采用电极法测定血钙;速率法测定血磷、碱性磷酸酶。大鼠右侧股骨HE染色,计量骨小梁平均宽度、骨小梁面积百分率。结果:与对照组比较,模型组大鼠体积骨密度明显降低,差异有统计学意义(P<0.05);模型组大鼠血钙、碱性磷酸酶明显降低,差异有统计学意义(P<0.05),血磷无差异;模型组大鼠骨小梁平均宽度及骨小梁面积百分率明显降低,差异有统计学意义。与模型组比较,九里香叶高剂量组大鼠体积骨密度明显增高,差异有统计学意义(P<0.05);九里香叶高剂量组大鼠血钙明显增高,差异有统计学意义(P<0.05),血磷无统计学意义;九里香叶低剂量组大鼠碱性磷酸酶明显降低,差异有统计学意义(P<0.05);九里香叶高剂量组骨小梁平均宽度及骨小梁面积百分率明显增高,差异有统计学意义(P<0.05)。结论:九里香叶影响去卵巢大鼠骨质疏松体积骨密度、血钙、碱性磷酸酶、骨小梁平均宽度及骨小梁面积百分率变化,具有抗骨质疏松作用。 展开更多
关键词 九里香 骨密度 血钙 血磷 碱性磷酸酶 骨组织形态学
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IMMUNOHISTOCHEMICAL STUDY ON S100 PROTEIN-POSITIVE DENDRITIC CELLS IN PATIENTS WITH GASTRIC CARCINOMA
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作者 黄建 黄怀德 +2 位作者 彭清璧 朱志建 余心如 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第2期57-61,共5页
The density of dendritic cells (DC) and macro-phages (Mφ) in tissue specimens of gastric carcinoma (GC n=65) was investigated by ABC im-munohistochemical method using anti-S100 protein and anti-lysozyme antibodies, a... The density of dendritic cells (DC) and macro-phages (Mφ) in tissue specimens of gastric carcinoma (GC n=65) was investigated by ABC im-munohistochemical method using anti-S100 protein and anti-lysozyme antibodies, and was compared with that in gastric ulcer (GU n=19), chronic atrophic gastritis (CAG n=28) and normal gastric mucosa (NGM n=15). The mean density if DC (cells/mm2) in GC (15.0 was significantly higher than that in NGM (3.8) and GU (8.3), but was remarkably lower when compared to that in CAG (29.5) (P<0.01). Statistically significant difference in the population density of DC was observed between well- and poorly-differentiated GC (P<0.01). With their unique dendritic processes, DC were mainly concentrated within dense lymphoid infiltrates or in the T-area of reactive lymphoid follicles and were interspersed among the tumor cells. In contrast, Mφ were present around the necrotic foci and were rarely seen within the non-necrotic neoplastic tissues. These data suggest that DC, which differ in morphology, distribution, number and function form Mφ may be more directly involved in the host immune reaction against tumor by acting as antigen presenting cells. 展开更多
关键词 IMMUNOHISTOCHEMICAL STUDY ON S100 PROTEIN-POSITIVE DENDRITIC CELLS IN PATIENTS WITH GASTRIC CARCINOMA DC GC
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异重流成因和异重岩沉积特征 被引量:41
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作者 Carlos Zavala 潘树新 《岩性油气藏》 CSCD 北大核心 2018年第1期1-18,共18页
河流在洪水期携带大量陆源碎屑,当其入湖或入海后,由于洪水密度大于周围水体的密度,洪水发生下沉并沿盆地底部长距离运移,形成陆源下潜流或异重流。异重流形成的相关沉积岩被统称为异重岩。异重岩通常由一个底部的反粒序单元和一个顶部... 河流在洪水期携带大量陆源碎屑,当其入湖或入海后,由于洪水密度大于周围水体的密度,洪水发生下沉并沿盆地底部长距离运移,形成陆源下潜流或异重流。异重流形成的相关沉积岩被统称为异重岩。异重岩通常由一个底部的反粒序单元和一个顶部的正粒序单元组成,反粒序单元反映了异重流能量的逐渐增强,正粒序反映了流体能量的逐渐减弱。异重流以3种方式搬运碎屑颗粒,即底载搬运、悬浮搬运和漂浮搬运。根据搬运方式的不同,异重岩分为3类岩相,即底载成因的B类岩相、悬载成因的S类岩相和漂浮物成因的L类岩相。异重流的沉积充填形成了河道、堤岸和朵叶体3类微相,内部岩相变化极为发育。异重岩的沉积特征虽然典型且较易识别,但是常被误认为是砂质碎屑流、滨岸相、三角洲相或河流相沉积。 展开更多
关键词 异重流 异重岩 浊流 深水沉积 内乌肯盆地 鄂尔多斯盆地 松辽盆地 西伯利亚盆地
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应用固态去耦合器减缓交流干扰的效果评价 被引量:6
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作者 宋晓琴 王文强 +1 位作者 蓝卫 徐承伟 《腐蚀与防护》 北大核心 2017年第11期885-888,共4页
受高压交流输电线路接地极影响,三层聚乙烯防腐蚀层(3LPE)管道容易受到较强的交流干扰,通常采取"固态去耦合器+接地极"的减缓措施。通过对交流减缓效果、阴极保护效果、排流影响范围、直流漏流量等现场参数进行测试,全面介绍... 受高压交流输电线路接地极影响,三层聚乙烯防腐蚀层(3LPE)管道容易受到较强的交流干扰,通常采取"固态去耦合器+接地极"的减缓措施。通过对交流减缓效果、阴极保护效果、排流影响范围、直流漏流量等现场参数进行测试,全面介绍了一种固态去耦合器性能评价方案,并指出现有固态去耦合器在使用过程中存在过度设计及故障电流下铜接地极易出现电偶腐蚀等风险。 展开更多
关键词 固态去耦合器 交流减缓 接地极 阴极保护
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Determination of Organochlorine and Nitrogen Containing Pesticide Residues in Water,Sediments and Fish Samples by Reverse Phase High Performance Liquid Chromatograph 被引量:9
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作者 Shahid Mahboob Ghazala +3 位作者 S.Sultana Muhammad Rafique Asi S.Nadeem A.S.Chaudhry 《Agricultural Science & Technology》 CAS 2009年第5期9-12,共4页
With high performance liquid chromatography, the concentrations of α-endosulfan, DDE, parathion methyl, isoproturon, atrazine, carbaryl and carbofuran were determined in farmed raised fish Labeo rohita of two weight ... With high performance liquid chromatography, the concentrations of α-endosulfan, DDE, parathion methyl, isoproturon, atrazine, carbaryl and carbofuran were determined in farmed raised fish Labeo rohita of two weight groups. All these pesticide residues were detected in fish meat samples. All these pesticide residues except isoproturon were identified in soil sediments, whereas all these pesticide residues except isoproturon, carbaryl and DDE were also present in water samples. DDT, heptachlor, β-endosulfan, chlorpyrifos, dimethoate, captan, cypermethrin, chlorobromuron and chlorotoluron were absent in all samples of water, sediments and fish flesh. The pesticide residues levels were in order of parathion methyl 〉 DDE 〉 carbofuran 〉 atrazine 〉 α-endosulfan 〉 isoproturan 〉 carbaryl. The concentrations of pesticides were higher in fish weighing 800 -1 300 g than in those weighing 250 -750 g. The DDE was remained highest in sediments, while that was not detected in water samples. The pesticides (endosulfan, parathion methyl, atrazine and carbofuran) had crossed their MRL values (0.001 μg/g) in water samples. 展开更多
关键词 Pesticrde residues ORGANOCHLORINE Nitrogen containing pesticides Reverse phase Chromatograph
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Theoretical investigation of sulfur defects on structural, electronic,and elastic properties of ZnSe semiconductor 被引量:2
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作者 Muhammad Zafar Shabbir Ahmed +2 位作者 M.Shakil M.A.Choudhary K.Mahmood 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期365-370,共6页
The structural, electronic, and elastic properties of ZnSe1-xSx for the zinc blende structures have been studied by using the density functional theory. The calculations were performed using the plane wave pseudopoten... The structural, electronic, and elastic properties of ZnSe1-xSx for the zinc blende structures have been studied by using the density functional theory. The calculations were performed using the plane wave pseudopotential method, as implemented in Quantum ESPRESSO. The exchange-correlation potential is treated with the local density approximation pz-LDA for these properties. Moreover, LDA+U approximation is employed to treat the "d" orbital electrons properly. A comparative study of the band gap calculated within both LDA and LDA+U schemes is presented. The analysis of results show considerable improvement in the calculation of band gap. The inclusion of compositional disorder increases the values of all elastic constants. In this study, it is found that elastic constants C11, C12, and C44 are mainly influenced by the compositional disorder. The obtained results are in good agreement with literature. 展开更多
关键词 first principles calculations density functional theory II–VI semiconductors electronic and elastic properties
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A low-voltage and energy-efficient full adder cell based on carbon nanotube technology 被引量:1
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作者 Keivan Navi Rabe'e Sharifi Rad +1 位作者 Mohammad Hossein Moaiyeri Amir Momeni 《Nano-Micro Letters》 SCIE EI CAS 2010年第2期114-120,共7页
Scaling problems and limitations of conventional silicon transistors have led the designers to exploit novel nano-technologies. One of the most promising and feasible nano-technologies is CNT(Carbon Nanotube) based tr... Scaling problems and limitations of conventional silicon transistors have led the designers to exploit novel nano-technologies. One of the most promising and feasible nano-technologies is CNT(Carbon Nanotube) based transistors. In this paper, a high-speed and energy-efficient CNFET(Carbon Nanotube Field Effect Transistor) based Full Adder cell is proposed for nanotechnology. This design is simulated in various supply voltages, frequencies and load capacitors using HSPICE circuit simulator. Significant improvement is achieved in terms of speed and PDP(Power-Delay-Product) in comparison with other classical and state-of-the-art CMOS and CNFET-based designs, existing in the literature. The proposed Full Adder can also drive large load capacitance and works properly in low supply voltages. 展开更多
关键词 CNFET LOW-VOLTAGE Full-Adder Minority-Function Nanotechnology
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General Solutions for Hydromagnetic Free Convection Flow over an Infinite Plate with Newtonian Heating, Mass Diffusion and Chemical Reaction 被引量:1
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作者 Constatin Fetecau Nehad Ali Shah Dumitru Vieru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第12期768-782,共15页
The problem of hydromagnetic free convection flow over a moving infinite vertical plate with Newtonian heating, mass diffusion and chemical reaction in the presence of a heat source is completely solved. Radiative and... The problem of hydromagnetic free convection flow over a moving infinite vertical plate with Newtonian heating, mass diffusion and chemical reaction in the presence of a heat source is completely solved. Radiative and porous effects are not taken into consideration but they can be immediately included by a simple rescaling of Prandtl number and magnetic parameter. Exact general solutions for the dimensionless velocity and concentration fields and the corresponding Sherwood number and skin friction coefficient are determined under integral form in terms of error function or complementary error function of Gauss. They satisfy all imposed initial and boundary conditions and can generate exact solutions for any problem with technical relevance of this type. As an interesting completion, uncommon in the literature, the differential equations which describe the thermal, concentration and momentum boundary layer, as well as the exact expressions for the thicknesses of thermal, concentration or velocity boundary layers were determined.Numerical results have shown that the thermal boundary layer thickness decreases for increasing values of Prandtl number and the concentration boundary layer thickness is decreasing with Schmidt number. Finally, for illustration,three special cases are considered and the influence of physical parameters on some fundamental motions is graphically underlined and discussed. The required time to reach the flow according with post-transient solution(the steady-state),for cosine/sine oscillating concentrations on the boundary is graphically determined. It is found that, the presence of destructive chemical reaction improves this time for increasing values of chemical reaction parameter. 展开更多
关键词 hydromagnetic free convection Newtonian heating heat source mass diffusion chemical reaction general solutions
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Unsteady flow of viscoelastic fluid between two cylinders using fractional Maxwell model 被引量:2
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作者 Muhammad Jamil Constantin Fetecau Corina Fetecau 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期274-280,共7页
The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms.The motion of the fluid is due to the inner cylinder that applies a tim... The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms.The motion of the fluid is due to the inner cylinder that applies a time dependent tor-sional shear to the fluid.The exact solutions for velocity and shear stress are presented in series form in terms of some generalized functions.They can easily be particularized to give similar solutions for Maxwell and Newtonian fluids.Fi-nally,the influence of pertinent parameters on the fluid motion,as well as a comparison between models,is highlighted by graphical illustrations. 展开更多
关键词 Maxwell fluid Fractional derivative Exact so-lutions Velocity field Shear stress Laplace and Hankel transforms
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