期刊文献+
共找到10,017篇文章
< 1 2 250 >
每页显示 20 50 100
弛豫铁电单晶的多功能特性及其器件应用 被引量:7
1
作者 罗豪甦 焦杰 +10 位作者 陈瑞 朱荣峰 张章 徐嘉林 赵静 王西安 林迪 陈建伟 狄文宁 鲁丽 朱莉莉 《人工晶体学报》 CAS 北大核心 2021年第5期783-802,共20页
以Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PMN-PT或PMNT)为代表的弛豫铁电单晶具有远高于常用锆钛酸铅Pb(Zr_(x) Ti_(1-x))O_(3)(PZT)陶瓷的压电性能,引起了基于新一代压电单晶的功能器件研究热潮。本研究团队在国际上率先利用Bridgman... 以Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PMN-PT或PMNT)为代表的弛豫铁电单晶具有远高于常用锆钛酸铅Pb(Zr_(x) Ti_(1-x))O_(3)(PZT)陶瓷的压电性能,引起了基于新一代压电单晶的功能器件研究热潮。本研究团队在国际上率先利用Bridgman方法生长出了大尺寸、高质量PMN-PT等弛豫铁电单晶(d_(33)~2000 pC/N,k_(33)~92%),并对PMN-PT等弛豫铁电单晶的生长、多层次微观结构和性能调控进行了多方面的研究,发现弛豫铁电单晶不仅具有超高压电性能,还具有突出的热释电性能、电光性能以及与磁致伸缩材料复合形成磁电复合材料的超高磁电耦合性能。本研究团队多年来一直在努力推动弛豫铁电单晶在医用超声换能器、热释电红外探测器、电光器件、磁电型弱磁传感器等各种器件的应用研究。本文主要总结了弛豫铁电单晶的多功能特性,并介绍了本研究团队在弛豫铁电单晶器件应用上的研究结果。 展开更多
关键词 弛豫铁电单晶 PMN-PT 器件应用 超声换能器 热释电红外探测器 电光器件 弱磁传感器
下载PDF
激光熔覆陶瓷颗粒增强高熵合金涂层的研究进展 被引量:1
2
作者 吴文宁 孙文磊 +1 位作者 陆靖 于江通 《应用激光》 CSCD 北大核心 2024年第5期38-48,共11页
利用激光熔覆技术制备的高熵合金涂层具有优异的综合力学性能,近年来成为金属材料邻域的研究热点。研究发现,在利用激光熔覆技术制备高熵合金涂层时,添加硬质陶瓷颗粒可以显著改善高熵合金涂层硬度、耐磨和耐腐蚀性能。归纳总结了硬质... 利用激光熔覆技术制备的高熵合金涂层具有优异的综合力学性能,近年来成为金属材料邻域的研究热点。研究发现,在利用激光熔覆技术制备高熵合金涂层时,添加硬质陶瓷颗粒可以显著改善高熵合金涂层硬度、耐磨和耐腐蚀性能。归纳总结了硬质陶瓷颗粒增强激光熔覆高熵合金涂层性能强化机理,接着从直接添加和原位合成两个方面综述了近几年常用的陶瓷颗粒增强相,详细总结了陶瓷颗粒增强相对高熵合金涂层显微组织和性能影响。最后,对激光熔覆陶瓷颗粒增强高熵合金复合涂层的发展前景进行了展望。 展开更多
关键词 激光熔覆 高熵合金 陶瓷颗粒 强化机理
原文传递
铁尾矿硫酸焙烧法提取铁制备α-Fe2O3光催化剂 被引量:5
3
作者 牟文宁 卢俊达 +3 位作者 罗绍华 雷雪飞 梁金生 段昕辉 《金属矿山》 CAS 北大核心 2020年第7期206-210,共5页
铁尾矿中富含铁、硅等有价元素,可作为制备功能性材料的原料。为考察硫酸焙烧法提取铁制备α-Fe2O3光催化剂的可能性,研究了焙烧过程中酸矿比、焙烧温度、焙烧时间对铁提取率的影响,得到适宜的焙烧条件为:酸矿比2∶1、焙烧温度280℃、... 铁尾矿中富含铁、硅等有价元素,可作为制备功能性材料的原料。为考察硫酸焙烧法提取铁制备α-Fe2O3光催化剂的可能性,研究了焙烧过程中酸矿比、焙烧温度、焙烧时间对铁提取率的影响,得到适宜的焙烧条件为:酸矿比2∶1、焙烧温度280℃、焙烧时间2 h,此时铁的提取率为89.80%。焙烧熟料经浸出、过滤制得含铁的硫酸盐溶液,采用中和沉淀法制备含铁的前驱体,再经400℃煅烧2 h制得粒径为40~50 nm、分散性较好的α-Fe2O3光催化剂。α-Fe2O3光催化降解甲基橙时,暗反应20 min吸附率为56%,光催化120 min时的降解率可达99%,表明α-Fe2O3具有良好的光催化性能。该研究结果实现了铁尾矿中铁的综合利用,促进光催化剂的实用化。 展开更多
关键词 铁尾矿 硫酸焙烧法 α-Fe2O3光催化剂 降解率
下载PDF
GA3处理对盐胁迫下5种牧草种子萌发及幼苗生长的影响 被引量:1
4
作者 崔文宁 孟静静 +4 位作者 张文香 路培 高培培 王茜 张存在 《草业科学》 CAS CSCD 北大核心 2024年第1期89-98,共10页
盐胁迫是限制种子萌发和幼苗生长的关键因子,适宜浓度的赤霉素(GA3)可有效缓解盐胁迫对种子造成的不利影响。为了解GA3对盐胁迫下牧草种子萌发和生长的缓解效应,筛选出促进盐胁迫下5种牧草种子萌发和幼苗生长的最佳GA3浓度,本研究以100 ... 盐胁迫是限制种子萌发和幼苗生长的关键因子,适宜浓度的赤霉素(GA3)可有效缓解盐胁迫对种子造成的不利影响。为了解GA3对盐胁迫下牧草种子萌发和生长的缓解效应,筛选出促进盐胁迫下5种牧草种子萌发和幼苗生长的最佳GA3浓度,本研究以100 mmol·L^(-1)的NaCl溶液模拟盐胁迫,以黑麦草(Lolium perenne)、‘朝牧1号’稗谷(Echinochloa crusgalli‘Chaomu1’)、羊草(Leymus chinensis)、紫花苜蓿(Medicago sativa)、白三叶(Trifolium repens)5种牧草种子为试材,选取不同浓度GA3进行浸种处理,测定其发芽率、发芽指数、根长、苗高、鲜重等指标。结果表明:GA3浸种可有效缓解盐胁迫对5种牧草种子萌发和幼苗生长造成的抑制作用,且不同浓度间作用差异显著(P<0.05)。150 mg·L^(-1)的GA3能有效促进黑麦草、羊草、紫花苜蓿和白三叶种子的萌发和幼苗生长;100 mg·L^(-1)的GA3能有效促进‘朝牧1号’稗谷的种子萌发,50 mg·L^(-1)的GA3能显著促进其种苗的生长。本研究结果对盐胁迫逆境下的牧草种植及土壤改良具有参考价值。 展开更多
关键词 赤霉素 盐胁迫 牧草种子 萌发 生长特性
下载PDF
钴高度分散于还原氧化石墨烯用于高级氧化降解有机污染物
5
作者 李文宁 陆敏 殷俞 《化工学报》 EI CSCD 北大核心 2024年第10期3793-3803,共11页
在废水处理技术中,基于过氧单硫酸盐(PMS)的高级氧化工艺被认为是降解有机污染物中最高效且绿色的方法之一。在激活PMS的方法中,负载过渡金属的催化剂由于金属离子溶出量低而广受关注,但却面临金属物种易团聚引发的降解活性低的问题。... 在废水处理技术中,基于过氧单硫酸盐(PMS)的高级氧化工艺被认为是降解有机污染物中最高效且绿色的方法之一。在激活PMS的方法中,负载过渡金属的催化剂由于金属离子溶出量低而广受关注,但却面临金属物种易团聚引发的降解活性低的问题。将Co负载在还原氧化石墨烯(rGO)上,经简单方法分别合成了Co高分散的QSCo-rGO和Co团聚的AGCo-rGO。XRD、HRTEM和元素分布研究表明,QSCo-rGO中的Co未发生金属团聚现象,实现了高度分散;而AGCo-rGO中的Co以CoO纳米颗粒的形式团聚。在激活PMS降解苯酚的反应中,QSCo-rGO可在30 min内完成100%的降解,而AGCo-rGO需要90 min。此外,QSCo-rGO展现出较好的可重复性和使用广泛性。机理研究表明,催化剂QSCo-rGO中的Co高度分散,暴露出更多活性金属位点,其通过激活PMS产生非自由基^(1)O_(2)从而高活性降解苯酚。本文可为设计增强降解活性的高级氧化催化剂提供思路。 展开更多
关键词 降解 催化剂 自由基 还原氧化石墨烯 过氧单硫酸盐
下载PDF
三元乙丙橡胶混炼胶的组分及配方分析
6
作者 吴文宁 张文浩 +4 位作者 汪胜 陆成华 孙子渊 李晓虹 屠迎锋 《橡胶工业》 CAS 2024年第8期624-629,共6页
对三元乙丙橡胶(EPDM)混炼胶的各组分进行分离并对配方进行分析。以正庚烷溶解EPDM混炼胶,将其有机组分与无机组分分离;有机组分在甲醇中沉淀后经二氯甲烷抽提,将EPDM与石蜡油分离;以盐酸溶解无机组分,将碳酸盐和氧化锌与白炭黑分离;采... 对三元乙丙橡胶(EPDM)混炼胶的各组分进行分离并对配方进行分析。以正庚烷溶解EPDM混炼胶,将其有机组分与无机组分分离;有机组分在甲醇中沉淀后经二氯甲烷抽提,将EPDM与石蜡油分离;以盐酸溶解无机组分,将碳酸盐和氧化锌与白炭黑分离;采用核磁共振氢谱、核磁共振扩散序谱、傅里叶红外光谱、X-射线衍射谱和X-射线光电子能谱,对各组分进行定性和定量分析,建立一套EPDM混炼胶组分的分析方法,有助于EPDM混炼胶的生产过程质量监控和配方改进。 展开更多
关键词 三元乙丙橡胶 混炼胶 组分 配方 测试与分析
下载PDF
WC含量对激光熔覆CoCrFeNiTi高熵合金涂层组织及耐腐蚀性能的影响
7
作者 吴文宁 孙文磊 +3 位作者 杨玉林 于江通 路程 包胜辉 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2024年第9期2642-2652,共11页
为了延长脱硫浆液循环泵叶轮的寿命,采用激光熔覆技术在脱硫浆液循环泵叶轮的母材30CrMnSiA钢表面制备了WC增强CoCrFeNiTi-WC_(x)(x=0,5,10,15,20,质量分数,%)高熵合金涂层,研究了WC含量对涂层的显微组织、力学和耐蚀性能影响。研究发现... 为了延长脱硫浆液循环泵叶轮的寿命,采用激光熔覆技术在脱硫浆液循环泵叶轮的母材30CrMnSiA钢表面制备了WC增强CoCrFeNiTi-WC_(x)(x=0,5,10,15,20,质量分数,%)高熵合金涂层,研究了WC含量对涂层的显微组织、力学和耐蚀性能影响。研究发现CoCrFeNiTi高熵合金涂层相组成为fcc(Fe-Ni)、bcc(Fe-Cr)、Laves(CoTi_(2))和AB-type(Ti的化合物),随着WC含量增加,Laves相衍射峰强度增强,且生成了新相碳化物(WC、Ti C、Cr_(7)C_(3)和Fe_(3)C)。CoCrFeNiTi高熵合金涂层主要组织为底部的胞状晶和顶部的等轴枝晶,随着WC含量增加,涂层组织主要为等轴枝晶,且晶粒尺寸逐渐细化。WC的加入提高了涂层的性能,其中CoCr FeNiTi-20%WC涂层硬度(HV_(0.2))最大,为6419 MPa,且摩擦系数(0.664)和磨损率(1.3×10^(2) μm^(3)·(s·N)^(-1))最小,耐磨性能最好,磨损机制主要为轻微的黏着磨损和磨粒磨损。此外,随着WC含量的增加,涂层表现出更低的腐蚀速率和腐蚀电流。其中,CoCrFeNiTi-20%WC涂层腐蚀电流最小,耐腐蚀性能最好。 展开更多
关键词 激光熔覆 高熵合金 WC颗粒 显微组织 耐腐蚀性
原文传递
Drainage pattern recognition method considering local basin shape based on graph neural network 被引量:2
8
作者 wenning Wang Haowen Yan +5 位作者 Xiaomin lu Yi He Tao Liu wende Li Pengbo Li Fang Xu 《International Journal of Digital Earth》 SCIE EI 2023年第1期593-619,共27页
Drainage pattern recognition is crucial for geospatial understanding and hydrologic modelling.Currently,drainage pattern recognition methods employ geometric measures of overall and local features of river networks bu... Drainage pattern recognition is crucial for geospatial understanding and hydrologic modelling.Currently,drainage pattern recognition methods employ geometric measures of overall and local features of river networks but lack measures of river basin unit shape features,so that potential correlations between river segments are usually ignored,resulting in poor drainage pattern recognition results.In order to overcome this problem,this paper proposes a supervised graph neural network method that considers the local basin unit shape of river networks.First,based on the overall hierarchy of the river networks,the confluence angle of river segments and the shape of river basin units,multiple drainage pattern classification features are extracted.Then,typical drainage pattern samples from the multi-scale NSDI and USGS databases are used to complete the training,validation and testing steps.Experimental results show that the drainage pattern indexes proposed can describe the characteristics of different drainage patterns.The method can effectively sample the adjacent river segments,flexibly transfer the associated pattern features among river segment neighbours,and aggregate the deeper characteristics of the river networks,thus improving the drainage pattern recognition accuracy relative to other methods and reliably distinguishing different drainage patterns. 展开更多
关键词 RIVER drainage pattern recognition Basin unit shape supervised learning graph neural networks
原文传递
Iron isotopic analyses of geological reference materials on MC-ICP-MS with instrumental mass bias corrected by three independent methods 被引量:2
9
作者 Chuanwei Zhu wenning lu +3 位作者 Yongsheng He Shan Ke Hongjie Wu Linan Zhang 《Acta Geochimica》 EI CAS CSCD 2018年第5期691-700,共10页
Here we report iron(Fe) isotopic data of three pure Fe solution standards(IRMM-014, GSB Fe, and NIST3126a) and five widely used geological reference materials(RMs) from the United States Geological Survey and Geologic... Here we report iron(Fe) isotopic data of three pure Fe solution standards(IRMM-014, GSB Fe, and NIST3126a) and five widely used geological reference materials(RMs) from the United States Geological Survey and Geological Survey of Japan obtained on a Neptune Plus multi-collector–inductively coupled plasma–mass spectrometer(MC-ICP-MS) in our laboratory over the past 3 years. The instrumental mass bias was corrected by three independent methods: sample-standard bracketing(SSB),Ni doping + SSB, and ^(57)Fe–^(58)Fe double spike + SSB.Measurements reveal that both the Ni doping and double spike methods helped calibrate short-term fluctuations in mass bias. Collectively, almost all measurements of RMs yielded δ^(56)Fe within ± 0.05 of recommended values,provided that each sample was measured four times on MC-ICP-MS. For the first time, new recommended values for NIST SRM3126a are reported(δ^(56)Fe = 0.363 ± 0.006,2SE, 95% CI; and δ^(57)Fe = 0.534 ± 0.010, 2SE). 展开更多
关键词 Iron isotopic analyses Sample-standardbracketing Double spike Ni doping Referencematerials Precision and accuracy
下载PDF
会计稳健性、融资约束与企业成长性--基于战略性新兴企业的实证研究
10
作者 丁文宁 陆新文 王苗苗 《长春理工大学学报(社会科学版)》 2020年第5期98-104,共7页
以2012—2018年战略性新兴企业作为研究对象,基于信号传递理论、MM理论、融资优序理论,在Basu构建的会计稳健性模型和Hadlock and Pierce构建的融资约束指标的基础上,实证检验了会计稳健性与战略性新兴企业成长性之间的关系,并进一步探... 以2012—2018年战略性新兴企业作为研究对象,基于信号传递理论、MM理论、融资优序理论,在Basu构建的会计稳健性模型和Hadlock and Pierce构建的融资约束指标的基础上,实证检验了会计稳健性与战略性新兴企业成长性之间的关系,并进一步探究融资约束的中介效用。研究发现:会计稳健性与企业成长性之间呈现正相关关系;会计稳健性与融资约束呈现负相关,稳健的会计信息对企业的融资约束起到抑制作用;融资约束在会计稳健性对企业成长性的影响过程中起到部分中介作用,会计稳健性通过缓解企业的融资约束程度促进战略性新兴企业的成长。 展开更多
关键词 会计稳健性 融资约束 企业成长性
下载PDF
中医药对慢性肾脏病5期(非透析)患者治疗优势的临床研究 被引量:15
11
作者 陈云 傅文宁 鲁盈 《世界中医药》 CAS 2018年第6期1337-1341,共5页
目的:通过观察健脾益肾法辨证治疗慢性肾脏病(CKD)5期(非透析)患者的临床疗效及安全性,初步探索中医药对终末期肾衰竭的治疗优势。方法:选取2015年11月至2016年6月金华市人民医院门诊或住院收治的符合纳入标准的CKD5期非透析患者50例,... 目的:通过观察健脾益肾法辨证治疗慢性肾脏病(CKD)5期(非透析)患者的临床疗效及安全性,初步探索中医药对终末期肾衰竭的治疗优势。方法:选取2015年11月至2016年6月金华市人民医院门诊或住院收治的符合纳入标准的CKD5期非透析患者50例,随机分为观察组和对照组,其中观察组30例,对照组20例。观察组予西医基础治疗联合中医健脾益肾法辨证治疗,对照组仅西医基础治疗,疗程为个24周。观察治疗前后2组患者中医主要症状及积分变化、中医证候疗效;肾功能、血红蛋白、血白蛋白、血钾、HCO_3^-等指标的改变;以及对不良事件和终点事件的分析,进行疗效评价和安全性观察。结果:观察组中医症状积分显著降低,组内或组间比较,差异有统计学意义(P<0.05),其中对畏寒肢冷、倦怠乏力、气短懒言、恶心呕吐等症状改善尤为明显;中医证候总有效率66.7%,对照组25%,差异有统计学意义(P<0.05)。与治疗前比较观察组血红蛋白、血白蛋白升高,营养不良-炎症评分(MIS)下降,差异有统计学意义(P<0.05),并明显优于对照组,差异有统计学意义(P<0.05);2组治疗后血肌酐均有升高、eGFR下降(P<0.05),但组间比较,差异有统计学意义(P>0.05)。2组在高钾血症、严重代谢性酸中毒等不良反应以及进入透析的终点事件发生率均无统计学差异。结论:中医药治疗CKD5期(非透析)患者可明显改善临床症状和营养状态,从而有助于延缓进入透析期。对该期患者在医生严密观察下应用中药治疗是相对安全的。 展开更多
关键词 慢性肾脏病 非透析 中医药 临床研究 肾功能
下载PDF
2018年CHINET中国细菌耐药性监测 被引量:398
12
作者 胡付品 郭燕 +76 位作者 朱德妹 汪复 蒋晓飞 徐英春 张小江 张朝霞 季萍 谢轶 康梅 王传清 王爱敏 徐元宏 沈继录 孙自镛 陈中举 倪语星 孙景勇 褚云卓 田素飞 胡志东 李金 俞云松 林洁 单斌 杜艳 郭素芳 魏莲花 邹凤梅 张泓 王春 胡云建 艾效曼 卓超 苏丹虹 汪瑞忠 房华 俞碧霞 赵勇 龚萍 郭大文 赵金英 刘文恩 李艳明 金炎 邵春红 温开镇 张贻荣 徐雪松 鄢超 喻华 黄湘宁 王山梅 楚亚菲 张利侠 马娟 周树平 周艳 朱镭 孟晋华 董芳 郑红艳 沈瀚 周万青 贾伟 李刚 吴劲松 卢月梅 李继红 刘江山 廖龙凤 顾洪芹 姜琳 贺雯 薛顺虹 冯佼 窦睿 岳春雷 《中国感染与化疗杂志》 CAS CSCD 北大核心 2020年第1期1-10,共10页
目的监测国内各省市主要医疗机构临床分离菌株对抗菌药物的敏感性。方法对国内主要地区44所医院临床分离菌按CHINET统一监测方案进行抗菌药物敏感性试验。按2018年CLSI文件标准判断结果。结果收集2018年1-12月上述医院临床分离菌共24484... 目的监测国内各省市主要医疗机构临床分离菌株对抗菌药物的敏感性。方法对国内主要地区44所医院临床分离菌按CHINET统一监测方案进行抗菌药物敏感性试验。按2018年CLSI文件标准判断结果。结果收集2018年1-12月上述医院临床分离菌共244843株,其中革兰阳性菌占28.2%,革兰阴性菌占71.8%。金黄色葡萄球菌和凝固酶阴性葡萄球菌中甲氧西林耐药株(MRSA和MRCNS)的平均检出率分别为34.0%和78.9%。MRSA和MRCNS对绝大多数测试药的耐药率均显著高于甲氧西林敏感株(MSSA和MSCNS)。MRSA中有92.2%的菌株对甲氧苄啶-磺胺甲唑敏感;MRCNS中有88.0%的菌株对利福平敏感;未发现万古霉素耐药株。肠球菌属中粪肠球菌对多数测试抗菌药物的耐药率均显著低于屎肠球菌,两者中均有少数万古霉素耐药株。肺炎链球菌非脑膜炎株儿童株中PSSP(89.4%)和PRSP(1.7%)所占比例较2016年有所下降。肠杆菌科细菌对碳青霉烯类抗生素仍高度敏感,多数菌属的耐药率低于17%(除克雷伯菌属外)。肺炎克雷伯菌对亚胺培南和美罗培南的耐药率分别从2005年的3.0%和2.9%上升到了2018年的25.0%和26.3%。与此同时,肺炎克雷伯菌每年的占比亦呈逐步上升趋势。不动杆菌属(鲍曼不动杆菌占92.5%)对亚胺培南和美罗培南的耐药率分别为73.2%和73.9%;铜绿假单胞菌对上述两药的耐药率分别为30.7%和25.8%;耐药率均呈上升趋势。结论临床分离菌对常见抗菌药物的耐药率仍呈增长趋势,尤其是碳青霉烯类耐药肺炎克雷伯菌,应加强医院感染防控措施和抗菌药物临床应用管理措施,在继续做好细菌耐药监测工作的同时加强实验室与临床的沟通,以发挥细菌耐药监测工作的最大价值。 展开更多
关键词 细菌耐药监测 药物敏感性试验 万古霉素耐药肠球菌 甲氧西林耐药葡萄球菌 青霉素耐药肺炎链球菌 碳青霉烯类耐药革兰阴性菌
下载PDF
The first offshore natural gas hydrate production test in South China Sea 被引量:172
13
作者 Jin-fa Li Jian-liang Ye +13 位作者 Xu-wen Qin Hai-jun Qiu Neng-you Wu Hai-long lu wen-wei Xie Jing-an lu Fei Peng Zhen-qiang Xu Cheng lu Zeng-gui Kuang Jian-gong Wei Qian-yong Liang Hong-feng lu Bei-bei Kou 《China Geology》 2018年第1期5-16,共12页
Natural gas hydrates (NGH)is one of key future clean energy resources.Its industrialized development will help remit the huge demand of global natural gas,relieve the increasing pressure of the environment, and play a... Natural gas hydrates (NGH)is one of key future clean energy resources.Its industrialized development will help remit the huge demand of global natural gas,relieve the increasing pressure of the environment, and play a vital role in the green sustainable growth of human societies.Based on nearly two decades' studying on the reservoir characteristics in the South China Sea (SCS)and the knowledge of reservoir system,the China Geological Survey (CGS)conducted the first production test on an optimal target selected in Shenhu area SCS in 2017.Guided by the "three-phase control"exploitation theory which focused on formation stabilization,technologies such as formation fluid extraction,well drilling and completing, reservoir stimulating,sand controlling,environmental monitoring,monitoring and preventing of secondary formation of hydrates were applied.The test lasted for 60 days from May 10^th when starting to pump, drop pressure and ignite to well killing on July 9^th,with gas production of 3.09×10^5 m^3 in total,which is a world record with the longest continuous duration of gas production and maximal gas yield.This successful test brings a significant breakthrough on safety control of NGH production. 展开更多
关键词 Natural gas HYDRATE (NGH) Production test Shenhu area SOUTH Chma SEA (SCS)
下载PDF
“智能电网+”研究综述 被引量:110
14
作者 鞠平 周孝信 +16 位作者 陈维江 余一平 秦川 李若梅 王成山 董旭柱 刘健 文劲宇 刘玉田 李扬 陈庆 陆晓 孙大雁 徐春雷 陈星莺 吴峰 马宏忠 《电力自动化设备》 EI CSCD 北大核心 2018年第5期2-11,共10页
智能电网SG(Smart Grid)是电力系统发展的必然趋势,其核心要义便是"智能",但目前智能水平还很低。而人工智能AI(Artificial Intelligence)技术取得了突破性进展,为SG的发展提供了重大机遇和强大支撑。为此,提出"智能电网... 智能电网SG(Smart Grid)是电力系统发展的必然趋势,其核心要义便是"智能",但目前智能水平还很低。而人工智能AI(Artificial Intelligence)技术取得了突破性进展,为SG的发展提供了重大机遇和强大支撑。为此,提出"智能电网+(Smart Grid Plus,SG+)"的概念,涵义是借助AI技术实现SG的升级版,使电网具有更高级、更深层的人工智能,从而进一步提升电网运行的安全性、经济性、可持续性。首先综述AI的研究进展,指出AI并非万能、也非无能;然后综述SG的研究进展,指出SG发展中"三高"(高比例新能源并网、高比例电力电子装置、高比例新负荷接入)和"三多"(多种能源相结合、多种网络相结合、多种主体相结合)的趋势。在回顾AI在电力行业应用的基础上,结合以深度学习为代表的第三代AI技术的发展,对深度学习等AI技术在SG适用的相关领域进行分析和展望。 展开更多
关键词 智能电网 人工智能 深度学习 智能电网+
下载PDF
A New Concept on Quality Marker for Quality Assessment and Process Control of Chinese Medicines 被引量:98
15
作者 Chang-xiao Liu Yi-yu Cheng +5 位作者 De-an Guo Tie-jun Zhang Ya-zhuo Li wen-bin Hou lu-qi Huang Hai-yu Xu 《Chinese Herbal Medicines》 CAS 2017年第1期3-13,共11页
Chinese medicine (CM) is the most typical conventional therapy compared with any other traditional or alternative medicine systems. The active components of CMs are either primary or secondary metabolites generated ... Chinese medicine (CM) is the most typical conventional therapy compared with any other traditional or alternative medicine systems. The active components of CMs are either primary or secondary metabolites generated by metabolic and biosynthetic enzymes in plants, protecting the plants from environmental stress. The characteristics of these metabolites are diverse, complicated and unique. In this paper, current approaches for quality assessment were extensively reviewed, a new concept of quality marker (Q-marker) was then proposed for CM quality assessment. Additionally, definition of the Q-marker, as well as the relevant methods, were discussed, on the basis of the biosynthetic pathways of secondary metabolites and source of biological active components. Study design of Q-marker is complex system for quality assessment and production process control of CM products with transitivity and traceability. Therefore, the system with characteristics of transmission and traceability is expected to be established for regulation of quality. Upon the concept which the transitivity and traceability in the quality assessment and production process control covered the entire process, such as raw materials, decoction slices, processing, extraction and production can be further enhanced. The transitivity and traceability will inevitably require close attention to "who, what, where, when, and why" details at each stage of Q-markers of CM production form raw materials to patent product. The establishing quality standards are enablers of many and various transitivity and traceability solutions, not a solution in them. It means that the transitivity and traceability system is readily link between products and across borders in quality. According to the thinking mode and methods of investigation on quality assessment of CM product, we focus on the entire process, in terms of safety and effectiveness and quality control. The standard preparation of CM or CM decoction is not only the basis for study of Q-marker, but also the 展开更多
关键词 Chinese medicine FORMULATION medicinal resource quality administration quality marker quality standard quantitative analysis secondary metabolites
原文传递
Clinical Features of Adult/Adolescent Atopic Dermatitis and Chinese Criteria for Atopic Dermatitis 被引量:85
16
作者 Ping Liu Yan Zhao +24 位作者 Zhang-Lei Mu Qian-Jin lu Qian-Jin L U Li Zhang Xu Yao Min Zheng Yi-wen Tang Xin-Xiano lu Xiu-Juan xia You-Kun Lin Yu-Zhen Li Cai-Xia Tu Zhi-Rong Yao Jin-Hua Xu Wei Li Wei Lai Hui-Min Yang Hong-Fu Xie Xiu-Ping Han Zhi-Qiang Xie Xiang Nong Zai-Pei Guo Dan-Qi Deng Tong-Xin Shi Jian-Zhong Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第7期757-762,共6页
Background: Atopic dermatitis (AD) is an inflammatory skin disease characterized by chronic recurrent dermatitis with profound itching. Most patients have personal and/or family history of atopic diseases. Several ... Background: Atopic dermatitis (AD) is an inflammatory skin disease characterized by chronic recurrent dermatitis with profound itching. Most patients have personal and/or family history of atopic diseases. Several criteria have been proposed for the diagnosis of AD. Although the clinical features of childhood AD have been widely studied, there has been less large-scale study on adult/adolescent AD. The aim of this study was to investigate the clinical features of adult/adolescent patients with chronic symmetrical eczemaJAD and to propose Chinese diagnostic criteria for adult/adolescent AD. Methods: A hospital-based study was performed. Forty-two dermatological centers participated in this study. Adult and adolescent patients (12 years and over) with chronic symmetrical eczema or AD were included in this study. Questionnaires were completed by both patients and-investigators. The valid questionnaires were analyzed using EpiData 3.1 and SPSS 17.0 software. Results: A total of 2662 valid questionnaires were collected (1369 male and 1293 female). Of all 2662 patients, 2062 (77.5%) patients had the disease after 12 years old, while only 600 (22.5%) patients had the disease before 12 years old, suggesting late-onset eczema/AD is common. Two thousand one hundred and thirty-nine (80.4%) patients had the disease for more than 6 months. One thousand one hundred and forty-four (43.0%) patients had a personal and/or family history of atopic diseases. One thousand five hundred and forty-eight (58.2%) patients had an elevated total serum IgE and/or eosinophilia and/or positive allergen-specific IgE. Based on these clinical and laboratory features, we proposed Chinese criteria for adult/adolescent AD. Of all 2662 patients, 60.3% were satisfied with our criteria, while only 48.2% satisfied with Hanifin Rajka criteria and 32.7% satisfied with Williams criteria, suggesting a good sensitivity of our criteria in adult/adolescent AD patients. Conclusion: Late-onset of eczema or AD is common. Th 展开更多
关键词 Adolescents and Adults Atopic Dermatitis Clinical Features Diagnostic Criteria ECZEMA
原文传递
Increasing the frequency of CIK cells adoptive immunotherapy may decrease risk of death in gastric cancer patients 被引量:83
17
作者 Jing-Ting Jiang, Chang-Ping Wu, lu-Jun Chen, Xiao Zheng, Department of Tumor Biological Treatment, Third Affiliated Hospital of Soochow University, Changzhou 213003, Jiangsu Province, China Yi-Bei Zhu, Jing Sun, Xue-Guang Zhang, Key Laboratory of Stem Cell of Jiangsu Province, Institute of Biotechnology, Key Laboratory of Clinical Immunology of Jiangsu Province, Soochow University, Suzhou 215123, Jiangsu Province, China Yue-Ping Shen, wen-Xiang Wei, Department of Medicine, Soochow University, Suzhou 215123, Jiangsu Province, China Bin-Feng lu, Department of Immunology, University of Pitts- burgh School of Medicine, Pittsburgh, PA 15261, United States 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第48期6155-6162,共8页
AIM: To analyze the correlation between cytokineinduced killer (CIK) cells adoptive immunotherapy and cancer-related death in gastric cancer patients. METHODS: One hundred and fifty-six gastric cancer patients after o... AIM: To analyze the correlation between cytokineinduced killer (CIK) cells adoptive immunotherapy and cancer-related death in gastric cancer patients. METHODS: One hundred and fifty-six gastric cancer patients after operation at the Third Affiliated Hospital of Soochow University were enrolled in this study. Their clinical data including demographic characteristics, operation time, tumor size, pathological type and staging, tumor metastasis, outcome of chemotherapy or CIK cells adoptive immunotherapy, survival time or time of death were collected with a standard structured questionnaire. Kaplan-Meier method was used to estimate the median survival time, and the 2- and 5- year survival rates. Hazard risk (HR) and 95% confidence interval (95% CI) of CIK cells adoptive immunotherapy for gastric cancer were calculated using the two-stage time-dependent covariates Cox model. RESULTS: The survival time of gastric cancer patients was longer after CIK cells adoptive immunotherapy than after chemotherapy (χ 2 = 10.907, P = 0.001). The median survival time of gastric cancer patients was also longer after CIK cells adoptive immunotherapy than after chemotherapy (49 mo vs 27 mo, P < 0.05). The 2- and 5-year survival rates of gastric cancer patients were significantly higher after CIK cells adoptive immunotherapy than after chemotherapy (73.5% vs 52.6%, 40.4% vs 23.9%, P < 0.05). A significant difference was observed in the survival curve for patients who received CIK cells adoptive immunotherapy (0, 1-10, 11-25, and over 25 frequencies) (χ 2 = 14.534, P = 0.002). The frequencies of CIK cells adoptive immunotherapy were significantly related with the decreasing risk of death in gastric cancer patients after adjustment for sex and age of the patients, tumor stage and relapse (HR = 0.54, 95% CI: 0.36-0.80) when the first stage Cox model was used to define the subjects who remained alive beyond 36 mo as survivors. However, no correlation was observed between the frequencies of death in CIK cells adoptive immunotherapy and the 展开更多
关键词 IMMUNOTHERAPY Cytokine-induced KILLER cells GASTRIC cancer Survival analysis Probability
下载PDF
Strong motion observations and recordings from the great Wenchuan Earthquake 被引量:71
18
作者 Li Xiaojun Zhou Zhenghua +5 位作者 Yu Haiyin wen Ruizhi lu Dawei Huang Moh Zhou Yongnian Cu Jianwen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第3期235-246,共12页
The National Strong Motion Observation Network System (NSMONS) of China is briefly introduced in this paper. The NSMONS consists of permanent free-field stations, special observation arrays, mobile observatories and... The National Strong Motion Observation Network System (NSMONS) of China is briefly introduced in this paper. The NSMONS consists of permanent free-field stations, special observation arrays, mobile observatories and a network management system. During the Wenchuan Earthquake, over 1,400 components of acceleration records were obtained from 460 permanent free-field stations and three arrays for topographical effect and structural response observation in the network system from the main shock, and over 20,000 components of acceleration records from strong aftershocks occurred before August 1, 2008 were also obtained by permanent free-field stations of the NSMONS and 59 mobile instruments quickly deployed after the main shock. The strong motion recordings from the main shock and strong aftershocks are summarized in this paper. In the ground motion recordings, there are over 560 components with peak ground acceleration (PGA) over 10 Gal, the largest being 957.7 Gal. The largest PGA recorded during the aftershock exceeds 300 Gal. 展开更多
关键词 Wenchuan Earthquake strong motion observation network mobile observation observation array strong motion record PGA
下载PDF
儿童健全成长取向下幼小衔接教育观差异分析——基于主要利益相关者的调查 被引量:71
19
作者 俞文 涂艳国 +1 位作者 李露 刘庆 《学前教育研究》 CSSCI 北大核心 2019年第4期16-31,共16页
为解决错综复杂的幼小衔接问题,各主要利益相关者都应建立基于儿童健全成长取向的幼小衔接教育观。本研究利用来自武汉市17所幼儿园和13所小学由家长、教师、管理者填写的2296份调查问卷数据,对当前主要利益相关者在这一幼小衔接教育观... 为解决错综复杂的幼小衔接问题,各主要利益相关者都应建立基于儿童健全成长取向的幼小衔接教育观。本研究利用来自武汉市17所幼儿园和13所小学由家长、教师、管理者填写的2296份调查问卷数据,对当前主要利益相关者在这一幼小衔接教育观上的差异进行分析,结果表明,在儿童生态发展因素上,家园之间和家校之间对幼小衔接的认识均存在显著差异,其中家长认识偏低;在儿童学习品质因素上,小学家长是幼小衔接中引发儿童学习养成问题的最主要冲突力量;在师生关系因素上,幼儿园群体与小学群体之间的衔接认识分歧最显著;在儿童教育期望因素上,幼儿园与小学家长、教师、管理者6类被试群体得分均偏低,其中小学教师不合理的教育期望最高,心理焦虑程度最大;在儿童时空环境因素上,幼儿园与小学教育管理者的衔接认识显著高于其他群体。为更好地促进幼小衔接,幼儿园与小学家长、教师和管理者应呵护儿童的"自成长力",建立基于相同价值取向的衔接观;应增强各主要利益相关者的教育责任感,尤其要提高弱势家长群体对儿童学习品质的认识;应明确幼小教育合作的整体设计,促进深度衔接,培养小学教师的积极教育期望。 展开更多
关键词 幼小衔接 主要利益相关者 教育观 儿童成长
下载PDF
Persistence and clearance of viral RNA in 2019 novel coronavirus disease rehabilitation patients 被引量:67
20
作者 Yun Ling Shui-Bao Xu +13 位作者 Yi-Xiao Lin Di Tian Zhao-Qin Zhu Fa-Hui Dai Fan Wu Zhi-Gang Song Wei Huang Jun Chen Bi-Jie Hu Sheng Wang En-Qiang Mao Lei Zhu wen-Hong Zhang Hong-Zhou lu 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第9期1039-1043,共5页
Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 ... Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease(COVID-19)remain unclear.This study analyzed the clearance time and factors influencing 2019 novel coronavirus(2019-nCoV)RNA in different samples from patients with COVID-19,providing further evidence to improve the management of patients during convalescence.Methods:The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20,2020 to February 10,2020 were collected retrospectively.The reverse transcription polymerase chain reaction(RT-PCR)results for patients’oropharyngeal swab,stool,urine,and serum samples were collected and analyzed.Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive(minimum 24 h sampling interval)negative RT-PCR results for viral RNA from oropharyngeal swabs.The effects of cluster of differentiation 4(CD4)+T lymphocytes,inflammatory indicators,and glucocorticoid treatment on viral nucleic acid clearance were analyzed.Results:In the 292 confirmed cases,66 patients recovered after treatment and were included in our study.In total,28(42.4%)women and 38 men(57.6%)with a median age of 44.0(34.0-62.0)years were analyzed.After in-hospital treatment,patients’inflammatory indicators decreased with improved clinical condition.The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5(6.0-11.0)days.By February 10,2020,11 convalescent patients(16.7%)still tested positive for viral RNA from stool specimens and the other 55 patients’stool specimens were negative for 2019-nCoV following a median duration of 11.0(9.0-16.0)days after symptom onset.Among these 55 patients,43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs,with 展开更多
关键词 COVID-19 2019-nCoV Nucleic acid detection GLUCOCORTICOID
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部