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(1-3)-β-D葡聚糖联合降钙素原、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究
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作者 黄强 王宇 +5 位作者 江渊 梁道斌 黄锐洁 秦小超 潘燕妮 和鹰 《中国真菌学杂志》 CSCD 2024年第1期21-24,29,共5页
目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将... 目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将其分为马尔尼菲篮状菌感染确诊组(血或组织液培育养出马尔尼菲篮状菌),简称A组(62例),及马尔尼菲篮状菌感染临床诊断组[根据临床症状、体征、血常规及(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞多指标诊断],简称B组(58例)。检测患者(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞的表达水平,采用受试者工作特征(receiver-operating characteristic,ROC)曲线下面积(area under the curve,AUC)评估上述指标联合检测对艾滋病患者感染马尔尼菲篮状菌的诊断效能。结果A组的(1-3)-β-D葡聚糖和PCT水平均高于B组,CD4^(+)T淋巴细胞个数低于B组(P<0.05);(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞联合检测的AUC为0.933,(1-3)-β-D葡聚糖单独检测的AUC是0.812,PCT单独检测的AUC为0.883,CD4^(+)T淋巴细胞单独检测的AUC是0.810,(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的AUC皆优于三项单独检测,表明(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的诊断价值皆优于单一指标诊断,且联合检测的特异度、约登指数分别为92.43%和0.580,均高于三项单独检测。结论(1-3)-β-D葡聚糖联合PCT和CD4^(+)T淋巴细胞多指标对艾滋病马尔尼菲篮状菌感染具有非常高的临床诊断价值,能够帮助医生分析出高危风险患者,及时制定治疗方案,同时也承担预后效果的判断依据,对治疗艾滋病马尔尼菲篮状菌感染具有非常重要的研究价值。 展开更多
关键词 (1-3)-β-d葡聚糖 PCT CD4^(+)T淋巴细胞 艾滋病 马尔尼菲篮状菌感染
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1例RHD-CE(3-7)-D基因重组与RHCE变异型患者的血清学与分子生物学分析
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作者 唐炳娣 蔡仲仁 +1 位作者 邓泳诗 伍昌林 《分子诊断与治疗杂志》 2024年第6期1183-1186,1190,共5页
目的 研究分析1例Rh血型弱D、弱cE患者的血清学与分子生物学特征,为该类患者的临床安全输血提供实验依据。方法 采用微柱凝胶卡法对患者红细胞进行ABO、RhDCcEe抗原的鉴定,同时采用试管法进行血型复核,抗人球蛋白卡法筛查不规则抗体;采... 目的 研究分析1例Rh血型弱D、弱cE患者的血清学与分子生物学特征,为该类患者的临床安全输血提供实验依据。方法 采用微柱凝胶卡法对患者红细胞进行ABO、RhDCcEe抗原的鉴定,同时采用试管法进行血型复核,抗人球蛋白卡法筛查不规则抗体;采用PCR-SSP法对RhDCcEe(RhD、RhC、Rhc、RhE、Rhe)基因型进行检测;三代全长测序技术对RHD/RHCE基因序列进行测序分析。结果 微柱凝胶卡法鉴定ABO、RhD、RhCcEe血型抗原的结果为:A抗原(-)、B抗原(-)、RhD(1+)、RhC(4+)、Rhc(1+)、RhE(1+)、Rhe(4+)、对照孔(-);试管法ABO、RhD、RhCcEe抗原鉴定该患者表型为:A抗原(-)、B抗原(-)、RhD(w+)、RhC(4+)、Rhc(w+)、RhE(w+)、Rhe(4+),对照管(-);抗人球蛋白卡法筛查患者不规则抗体阴性;PCR-SSP法血型基因分型RhDCcEe结果:RhD(+)、RhC(+)、Rhc(+)、RhE(+)、Rhe(+);RHD/RHCE基因结果:RHD单倍体1为外显子1-10全缺失,而单倍体2为外显子RHD-CE基因重组融合,且确认其重组类型为RHD-CE(3-7)-D,起点在外显子2(g.20238-20312之间),终点在外显子8(g49184-50480之间),同时RHCE基因第6外显子存在新碱基点突变RHCE*cE(827C>A)。结论RHD-CE(3-7)-D基因重组融合与RHCE*cE(827C>A)新等位基因突变可能引起D、cE血型抗原弱表达,为临床安全输血提供了重要的实验数据支持。 展开更多
关键词 RhD/cE弱抗原 RHD-CE(3-7)-d重组 RHCE*cE(827C>A) 三代全长测序
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Analysis of Tidal Current Energy Potential in the Major Channels of the Bohai Strait Based on Delft3D
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作者 MA Pengcheng SHI Hongyuan +2 位作者 XUE Huaiyuan LI Pingping SUN Yongkang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期859-870,共12页
The utilization and development of tidal current energy can help alleviate the current energy shortage,improve the global ecological environment,and maintain sustainable development.In this study,numerical simulation ... The utilization and development of tidal current energy can help alleviate the current energy shortage,improve the global ecological environment,and maintain sustainable development.In this study,numerical simulation is carried out on a rectangular grid using Delft3D.The tidal current energy potential of the major channels in the Bohai Strait is further simulated and estimated by comparing the simulated and measured data.Results show that the flow module in Delft3D has good modeling ability for the assessment of tidal current energy potential.The average flow velocity,maximum flow velocity,and energy flow density are consistent.The Laotieshan Channel,located in the northern part of the Bohai Strait,shows a large tidal current energy potential.The maximum flow velocity of this channel can reach 2 m s-1,and the maximum energy flow density can exceed 500 W m-2.The tidal current energy in the Laotieshan Channel is more than 10 times that in other channels.Therefore,this study advocates for the continued exploration and exploitation of the tidal current energy resources in the Laotieshan Channel. 展开更多
关键词 Delft3D Bohai Strait tidal current energy numerical simulation power density
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基于二萘并[2,3-B∶2′,3′-D]呋喃基团的高效窄发射蓝光OLED器件
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作者 王小伟 袁江波 +4 位作者 马佩兰 闫自强 崔志远 孙军 彭其明 《发光学报》 EI CAS CSCD 北大核心 2024年第9期1503-1510,共8页
高效率窄光谱蓝色有机电致发光器件(OLED)是柔性显示领域的研究重点之一。本文以二萘并[2,3-B∶2′,3′-D]呋喃为弱电子受体、N-(4-联苯基)-1-萘胺作为电子给体设计合成了一种D-A-D型蓝光分子DPF-NA,其在正己烷溶液中的发射峰位于441 n... 高效率窄光谱蓝色有机电致发光器件(OLED)是柔性显示领域的研究重点之一。本文以二萘并[2,3-B∶2′,3′-D]呋喃为弱电子受体、N-(4-联苯基)-1-萘胺作为电子给体设计合成了一种D-A-D型蓝光分子DPF-NA,其在正己烷溶液中的发射峰位于441 nm。理论计算与光物理测试结果显示DPF-NA具有杂化局域电荷转移激发态(HLCT)特性,兼具局域态(LE)高发光效率与电荷转移态(CT)高激子利用率特征,在二氯甲烷溶液中的光致发光量子效率(PLQY)为81.2%。基于质量分数3%DPF-NA掺杂浓度的OLED器件电致发光(EL)峰位于455 nm,半峰宽(FWHM)仅为26 nm,CIE(x,y)坐标为(0.14,0.08),最大外量子效率(EQEmax)为6.76%。 展开更多
关键词 有机电致发光器件 二萘并[2 3-B∶2′ 3-d]呋喃 蓝光 激子利用 外量子效率
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Critical current degradation in an epoxy-impregnated rare-earth Ba_(2)Cu_(3)O_(7-x)coated conductor caused by damage during a quench
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作者 Donghui LIU Huadong YONG Youhe ZHOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第9期1557-1572,共16页
High-temperature superconducting(HTS)rare-earth Ba_(2)Cu_(3)O_(7-x)(REBCO)coated conductors(CCs)have significant potential in high-current and high-field applications.However,owing to the weak interface strength of th... High-temperature superconducting(HTS)rare-earth Ba_(2)Cu_(3)O_(7-x)(REBCO)coated conductors(CCs)have significant potential in high-current and high-field applications.However,owing to the weak interface strength of the laminated composite REBCO CCs,the damage induced by the thermal mismatch stress under a combination of epoxy impregnation,cooling,and quenching can cause premature degradation of the critical current.In this study,a three-dimensional(3D)electromagnetic-thermal-mechanical model based on the H-formulation and cohesive zone model(CZM)is developed to study the critical current degradation characteristics in an epoxy-impregnated REBCO CC caused by the damage during a quench.The temperature variation,critical current degradation of the REBCO CC,and its degradation onset temperature calculated by the numerical model are in agreement with the experimental data taken from the literature.The delamination of the REBCO CC predicted by the numerical model is consistent with the experimental result.The numerical results also indicate that the shear stress is the main contributor to the damage propagation inside the REBCO CC.The premature degradation of the critical current during a quench is closely related to the interface shear strength inside the REBCO CC.Finally,the effects of the coefficient of thermal expansion(CTE)of the epoxy resin,thickness of the substrate,and substrate material on the critical current degradation characteristics of the epoxy-impregnated REBCO CC during a quench are also discussed.These results help us understand the relationship between the current-carrying degradation and damage in the HTS applications. 展开更多
关键词 epoxy-impregnated rare-earth Ba_(2)Cu_(3)O_(7-x)(REBCO)coated conductor(CC) QUENCH DAMAGE critical current degradation shear stress
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New 4-imino-4H-Chromeno[2,3-d]Pyrimidin-3(5H)-Amine: Synthesis, Cytotoxic Effects on Tumoral Cell Lines and in Silico ADMET Properties
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作者 Marwa Dhiabi Sirine Karoui +7 位作者 Mehdi Fakhfakh Souhir Abid Emmanuelle Limanton Rémy Le Guével Thierry Charlier Ludovic Paquin Jean-Pierre Bazureau Houcine Ammar 《International Journal of Organic Chemistry》 2024年第3期107-122,共16页
The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was establishe... The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-IR, NMR and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound. 展开更多
关键词 2-Amino-4H-Chromene 4H-Chromeno[2 3-d]Pyrimidin-3(5H)-Amine Microwave Irradiation Tumoral Cell Line in Silico ADMET
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血浆(1-3)-β-D葡聚糖诊断新生儿侵袭性真菌感染的价值
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作者 邵碧波 刘思佳 李益廷 《中文科技期刊数据库(文摘版)医药卫生》 2024年第3期0001-0004,共4页
探讨在针对新生儿侵袭性真菌感染的诊断中使用血浆(1-3)-β-D葡聚糖能够产生的诊断效能。方法 选取2021年1月到2022年2月因为侵袭性真菌感染于医院寻求医疗干预的新生儿总共60例作为本次研究的一部分研究对象记为1组;另外选取60例健康... 探讨在针对新生儿侵袭性真菌感染的诊断中使用血浆(1-3)-β-D葡聚糖能够产生的诊断效能。方法 选取2021年1月到2022年2月因为侵袭性真菌感染于医院寻求医疗干预的新生儿总共60例作为本次研究的一部分研究对象记为1组;另外选取60例健康婴儿作为2组;统计、对比两组患者的血浆(1-3)-β-D葡聚糖水平、CD4+T淋巴细胞数水平;整理PCR技术针对1组患者诊断结果,将其与血浆(1-3)-β-D葡聚糖诊断侵袭性真菌感染的诊断效能进行对比。结果 研究结果显示1组患者的血浆(1-3)-β-D葡聚糖水平、CD4+T淋巴细胞数水平较之于2组患者存在明显差异,1组患者血浆(1-3)-β-D葡聚糖水平更高,而CD4+T淋巴细胞数水平明显更低;P<0.05。在针对诊断效能的考察上,血浆(1-3)-β-D葡聚糖诊断效能和PCR诊断结果之间在灵敏度、特异度方面差异不大,P>0.05。结论 针对罹患侵袭性真菌感染的新生儿使用血浆(1-3)-β-D葡聚糖进行检查,一定程度上能够确保诊断结果的严谨程度,可使用。 展开更多
关键词 侵袭性真菌感染 诊断 血浆(1-3)-β-d葡聚糖
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血浆(1,3)-β-D葡聚糖检测在侵袭性真菌感染诊断中的价值分析
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作者 王珍珍 《中国科技期刊数据库 医药》 2024年第9期0150-0153,共4页
研究血浆(1,3)-β-D葡聚糖检测技术(G实验)应用于侵袭性真菌感染(IFI)诊断中的应用价值。方法 选择我院在2023年1月至2024年1月期间收治的100例高危型侵袭型真菌感染患者,应用MB-80微生物快速检测动态系统以及对应的试剂对患者的血浆(1,... 研究血浆(1,3)-β-D葡聚糖检测技术(G实验)应用于侵袭性真菌感染(IFI)诊断中的应用价值。方法 选择我院在2023年1月至2024年1月期间收治的100例高危型侵袭型真菌感染患者,应用MB-80微生物快速检测动态系统以及对应的试剂对患者的血浆(1,3)-β-D葡聚糖进行检测,分析真菌培养、G实验和联合检测结果;三种方法的诊断效能;三种方法的ROC曲线。结果 确诊IFI阳性共28例,阴性共72例;联合检测的诊断效能高于真菌培养或者G实验。联合检测面积高于单一检测。结论 在侵袭性真菌感染的诊断中,应用血浆(1,3)-β-D葡聚糖检测,诊断效能良好,在和传统真菌培养技术联合检测下,可进一步提升诊断效能。 展开更多
关键词 血浆(1 3)-β-d葡聚糖检测技术 侵袭性真菌感染 诊断效能
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Parallel computing approach for efficient 3-D X-ray-simulated image reconstruction 被引量:1
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作者 Ou-Yi Li Yang Wang +1 位作者 Qiong Zhang Yong-Hui Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期122-136,共15页
Accurate 3-dimensional(3-D)reconstruction technology for nondestructive testing based on digital radiography(DR)is of great importance for alleviating the drawbacks of the existing computed tomography(CT)-based method... Accurate 3-dimensional(3-D)reconstruction technology for nondestructive testing based on digital radiography(DR)is of great importance for alleviating the drawbacks of the existing computed tomography(CT)-based method.The commonly used Monte Carlo simulation method ensures well-performing imaging results for DR.However,for 3-D reconstruction,it is limited by its high time consumption.To solve this problem,this study proposes a parallel computing method to accelerate Monte Carlo simulation for projection images with a parallel interface and a specific DR application.The images are utilized for 3-D reconstruction of the test model.We verify the accuracy of parallel computing for DR and evaluate the performance of two parallel computing modes-multithreaded applications(G4-MT)and message-passing interfaces(G4-MPI)-by assessing parallel speedup and efficiency.This study explores the scalability of the hybrid G4-MPI and G4-MT modes.The results show that the two parallel computing modes can significantly reduce the Monte Carlo simulation time because the parallel speedup increment of Monte Carlo simulations can be considered linear growth,and the parallel efficiency is maintained at a high level.The hybrid mode has strong scalability,as the overall run time of the 180 simulations using 320 threads is 15.35 h with 10 billion particles emitted,and the parallel speedup can be up to 151.36.The 3-D reconstruction of the model is achieved based on the filtered back projection(FBP)algorithm using 180 projection images obtained with the hybrid G4-MPI and G4-MT.The quality of the reconstructed sliced images is satisfactory because the images can reflect the internal structure of the test model.This method is applied to a complex model,and the quality of the reconstructed images is evaluated. 展开更多
关键词 Parallel computing Monte Carlo Digital radiography 3-d reconstruction
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血清25-羟维生素-D3 超敏C反应蛋白及心电图参数与ST段抬高型心肌梗死患者介入治疗后发生恶性心律失常的关系 被引量:12
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作者 李永慧 王小玲 +2 位作者 原文龙 王蕾 屈艳玲 《河北医学》 CAS 2023年第2期265-270,共6页
目的:探讨血清25-羟维生素-D3(25-hydroxyvitamin D3,25-(OH)-D3)、超敏C反应蛋白(High sensitivity C-reactive protein,hs-CRP)、心电图参数变化与ST段抬高型心肌梗死(ST segment elevation myocardial infarction,STEMI)患者经皮冠... 目的:探讨血清25-羟维生素-D3(25-hydroxyvitamin D3,25-(OH)-D3)、超敏C反应蛋白(High sensitivity C-reactive protein,hs-CRP)、心电图参数变化与ST段抬高型心肌梗死(ST segment elevation myocardial infarction,STEMI)患者经皮冠脉介入术(Percutaneous coronary intervention,PCI)后发生恶性心律失常的关系。方法:选取我院2020年1月至2022年6月实施PCI治疗的193例STEMI患者作为研究对象,根据患者术后72h内是否发生恶性心律失常分为心律失常组38例、对照组155例,对比两组患者入院12h内的25-(OH)-D3、hs-CRP、血清电解质、血常规指标、血脂指标、心肌酶学指标,并对患者PCI术后实施连续动态心电图监测,对比两组患者心电图碎裂QRS波、校正Tp-e间期(Corrected Tp-e interval,Tp-ec)、QT离散度(QT dispersion,Qtd),并采用Logistic回归模型分析上述指标与STEMI患者PCI术后发生恶性心律失常的关系。结果:心律失常组患者的血清25-(OH)-D3水平低于对照组,心律失常组患者的血清hs-CRP、Tp-ec测定值、Qtd测定值、碎裂QRS波检出率均高于对照组,上述指标组间差异均具有统计学意义(P<0.05);心律失常组患者的白细胞(White blood cell,WBC)、肌钙蛋白I(Troponin I,cTnI)、肌酸激酶同工酶(Creatine kinase isoenzyme,CK-MB)、肌红蛋白(Myoglobin,MYO)、K+、Mg 2+水平均高于对照组患者,差异具有统计学意义(P<0.05);Logistic回归模型结果显示:cTnI、CK-MB、K+、hs-CRP、Tp-ec、Qtd增高,碎裂QRS波阳性会显著增大STEMI患者PCI后发生恶性心律失常的风险(P<0.05);血清25-(OH)-D3水平增高会降低STEMI患者PCI后发生恶性心律失常的风险(P<0.05)。结论:STEMI患者血清25-(OH)-D3水平降低、hs-CRP增高、PCI术后Tp-ec、Qtd增高、出现碎裂QRS波会增大患者出现恶性心律失常的风险。 展开更多
关键词 25-羟维生素-d3 超敏C反应蛋白 动态心电图 ST段抬高型心肌梗死 经皮冠脉介入术 恶性心律失常
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Fe_(3)O_(4)/BiOBr/BiOI的制备及降解2,4-D的性能研究 被引量:2
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作者 刘家豪 张梦朝 +5 位作者 文斯捷 谢剑锋 董丽 杨代琼 党晶晶 卢昶雨 《应用化工》 CAS CSCD 北大核心 2023年第1期47-52,共6页
采用水热法制备了微米球花状结构的Fe_(3)O_(4)/BiOBr/BiOI复合材料,通过SEM、XRD、XPS和UV-Vis等手段对催化剂进行表征分析。结果表明,该催化剂对2,4-D具有高效的光降解性能和光催化效率(80 min,88%)。降解速率常数为2.498×10^(-2... 采用水热法制备了微米球花状结构的Fe_(3)O_(4)/BiOBr/BiOI复合材料,通过SEM、XRD、XPS和UV-Vis等手段对催化剂进行表征分析。结果表明,该催化剂对2,4-D具有高效的光降解性能和光催化效率(80 min,88%)。降解速率常数为2.498×10^(-2)min^(-1),分别是Br∶I=5∶5(K=2.004×10^(-2)min^(-1))、BiOBr(K=1.289×10^(-2)min^(-1))和BiOI(K=6.98×10-3min-1)的1.25倍、1.94倍与3.58倍。这是由于Fe_(3)O_(4)/BiOBr/BiOI复合材料内部形成了异质结,利于光生载流子的分离。此外,5次循环实验后,降解效率保持在82.9%,证明该催化剂稳定、可回收、可磁分离。 展开更多
关键词 Fe_(3)O_(4)/BiOBr/BiOI 光催化 2 4-d 复合材料
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Numerical study on residual current and its impact on mass transport in the Hangzhou Bay and the Changjiang Estuary I. A3-D joint model of the Hangzhou Bay and the Changjiang Estuary 被引量:5
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作者 Zhu Shouxian 1,2 ,Shi Fengyan 1,Zhu Jianrong 1,Ding Pingxing 11 .StateKeyLaboratoryofEstuarineandCoastalResearch ,EastChinaNormalUniversity ,Shanghai 2 0 0 0 6 2 ,China   2.MeteorologyInstituteofthePLAScienceandEngineeringUniversity ,Nanjing 2 11 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第1期1-13,共13页
A 3-D numerical model is set up in a large domain covering the Hangzhou Bay and the Changjiang Estuary based on the ECOM model in orthogonal curvilinear coordinates.The numerical schemes for baroclinic pressure gradie... A 3-D numerical model is set up in a large domain covering the Hangzhou Bay and the Changjiang Estuary based on the ECOM model in orthogonal curvilinear coordinates.The numerical schemes for baroclinic pressure gradient (BPG)terms and convective terms are improved in the paper according to the characteristics of velocity field and mass transport in the area.The model is validated by the simulations of residual current and salinity transport in the Hangzhou Bay and the Changjiang Estuary. 展开更多
关键词 3-d numerical model the Hangzhou Bay the Changjiang Estuary baroclinic pressure gradient convective
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Building 3-D Human Data Based on Handed Measurement and CNN
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作者 Bich Nguyen Binh Nguyen +3 位作者 Hai Tran Vuong Pham Le Nhi Lam Thuy Pham The Bao 《Computers, Materials & Continua》 SCIE EI 2023年第2期2431-2441,共11页
3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment industry.The application of human body models to the garment industry is necessary to respond to the increasin... 3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment industry.The application of human body models to the garment industry is necessary to respond to the increasing personalization demand and still guarantee aesthetics.This paper proposes amethod to construct 3-D human models by applying deep learning.We calculate the location of the main slices of the human body,including the neck,chest,belly,buttocks,and the rings of the extremities,using pre-existing information.Then,on the positioning frame,we find the key points(fixed and unaltered)of these key slices and update these points tomatch the current parameters.To add points to a star slice,we use a deep learning model tomimic the form of the human body at that slice position.We use interpolation to produce sub-slices of different body sections based on the main slices to create complete body parts morphologically.We combine all slices to construct a full 3-D representation of the human body. 展开更多
关键词 3-d human model deep learning INTERPOLATION
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具有快响应速度和低暗电流的垂直MSM型CsPbBr_(3)薄膜光电探测器
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作者 程学明 崔文宇 +3 位作者 祝鲁平 王霞 刘宗明 曹丙强 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第20期277-285,共9页
卤化物钙钛矿具有优异的电学和光学性能,是光电子器件中理想的有源层候选材料,特别是在高性能光探测方面显示出更具竞争力的发展前景,其中全无机钙钛矿CsPbBr_(3)因其良好的环境稳定性而被广泛关注.本文报道了一种具有快响应速度和低暗... 卤化物钙钛矿具有优异的电学和光学性能,是光电子器件中理想的有源层候选材料,特别是在高性能光探测方面显示出更具竞争力的发展前景,其中全无机钙钛矿CsPbBr_(3)因其良好的环境稳定性而被广泛关注.本文报道了一种具有快响应速度和低暗电流的垂直MSM型CsPbBr_(3)薄膜光电探测器.由于采用垂直结构缩短了光生载流子的渡越距离,器件具有超快的响应速度63μs,比传统平面MSM型光电探测器提高了两个数量级.然后,通过在p型CsPbBr_(3)与Ag电极之间旋涂一层TiO_(2)薄膜,提升了界面光生载流子的分离效率,实现了钙钛矿薄膜与金属电极间的物理钝化,从而大大降低了器件的暗电流,在–1 V的偏压下暗电流只有–4.81×10^(-12) A.此外,该种垂直MSM型CsPbBr_(3)薄膜光电探测器还具有线性动态范围大(122 dB)、探测率高(1.16×10^(12) Jones)和光稳定性好等诸多优点.通过Sentaurus TCAD模拟发现,电荷传输层可以选择性的阻挡载流子传输,从而起到降低暗电流的作用,Sentaurus TCAD模拟结果与实验数据吻合,揭示了电荷传输层降低器件暗电流的内在物理机制. 展开更多
关键词 CsPbBr_(3) 光电探测器 垂直结构 低暗电流 高响应速度
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Conical Sonic-Supersonic Solutions for the 3-D Steady Full Euler Equations
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作者 Yanbo Hu Xingxing Li 《Communications on Applied Mathematics and Computation》 2023年第3期1053-1096,共44页
This paper concerns the sonic-supersonic structures of the transonic crossflow generated by the steady supersonic flow past an infinite cone of arbitrary cross section.Under the conical assumption,the three-dimensiona... This paper concerns the sonic-supersonic structures of the transonic crossflow generated by the steady supersonic flow past an infinite cone of arbitrary cross section.Under the conical assumption,the three-dimensional(3-D)steady Euler equations can be projected onto the unit sphere and the state of fluid can be characterized by the polar and azimuthal angles.Given a segment smooth curve as a conical-sonic line in the polar-azimuthal angle plane,we construct a classical conical-supersonic solution near the curve under some reasonable assumptions.To overcome the difficulty caused by the parabolic degeneracy,we apply the characteristic decomposition technique to transform the Euler equations into a new degenerate hyperbolic system in a partial hodograph plane.The singular terms are isolated from the highly nonlinear complicated system and then can be handled successfully.We establish a smooth local solution to the new system in a suitable weighted metric space and then express the solution in terms of the original variables. 展开更多
关键词 Three-dimensional(3-d)full Euler equations Conical flow Conical-sonic Characteristic decomposition Classical solution
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Adaptive Window Based 3-D Feature Selection for Multispectral Image Classification Using Firefly Algorithm
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作者 M.Rajakani R.J.Kavitha A.Ramachandran 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期265-280,共16页
Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafte... Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafted feature sets are used which are not adaptive for different image domains.To overcome this,an evolu-tionary learning method is developed to automatically learn the spatial-spectral features for classification.A modified Firefly Algorithm(FA)which achieves maximum classification accuracy with reduced size of feature set is proposed to gain the interest of feature selection for this purpose.For extracting the most effi-cient features from the data set,we have used 3-D discrete wavelet transform which decompose the multispectral image in all three dimensions.For selecting spatial and spectral features we have studied three different approaches namely overlapping window(OW-3DFS),non-overlapping window(NW-3DFS)adaptive window cube(AW-3DFS)and Pixel based technique.Fivefold Multiclass Support Vector Machine(MSVM)is used for classification purpose.Experiments con-ducted on Madurai LISS IV multispectral image exploited that the adaptive win-dow approach is used to increase the classification accuracy. 展开更多
关键词 Multispectral image modifiedfirefly algorithm 3-d feature extraction feature selection multiclass support vector machine CLASSIFICATION
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AlN/β-Ga_(2)O_(3)HEMT直流特性仿真
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作者 贺小敏 唐佩正 +4 位作者 张宏伟 张昭 胡继超 李群 蒲红斌 《人工晶体学报》 CAS 北大核心 2024年第5期766-772,共7页
本文利用器件仿真软件对AlN/β-Ga_(2)O_(3)高电子迁移率晶体管(HEMT)器件的直流特性进行研究。由于AlN具有很强的极化效应,在AlN/β-Ga_(2)O_(3)异质结界面处产生高浓度二维电子气(2DEG),使AlN/β-Ga_(2)O_(3)异质结基HEMT具有更加优... 本文利用器件仿真软件对AlN/β-Ga_(2)O_(3)高电子迁移率晶体管(HEMT)器件的直流特性进行研究。由于AlN具有很强的极化效应,在AlN/β-Ga_(2)O_(3)异质结界面处产生高浓度二维电子气(2DEG),使AlN/β-Ga_(2)O_(3)异质结基HEMT具有更加优越的器件性能。理论计算得到AlN/β-Ga_(2)O_(3)异质结界面处产生的面电荷密度为2.75×10^(13) cm^(-2)。通过分析器件的能带结构、沟道电子浓度分布,研究AlN势垒层厚度、栅极长度、栅漏间距,以及金属功函数等参数对器件转移特性和输出特性的影响。结果表明:随着AlN势垒层厚度的增大,阈值电压减小,最大跨导减小,沟道电子浓度增大使饱和漏电流增大;随着栅极长度缩短,跨导增大,当栅极长度缩短至0.1μm时,器件出现了短沟道效应,并且随着栅极长度的缩短,栅下沟道区电子浓度增大,而电子速度基本不变,导致饱和漏电流增大,导通电阻减小,并且器件的饱和特性变差;随着栅漏间距的增大,跨导增大,沟道区电子浓度不变,而电子速度略有增加,导致饱和漏电流增大;肖特基栅金属功函数的增加会增大阈值电压,不会改变器件跨导,沟道电子浓度减小导致饱和漏电流减小。上述结论为后面的器件的优化改进提供了理论依据。 展开更多
关键词 β-Ga_(2)O_(3) ALN HEMT 阈值电压 跨导 饱和漏电流
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NiO/β-Ga_(2)O_(3)heterojunction diodes with ultra-low leakage current below 10^(-10)A and high thermostability
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作者 黄义 杨稳 +5 位作者 王琦 高升 陈伟中 唐孝生 张红升 刘斌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期530-534,共5页
The 10 nm p-NiO thin film is prepared by thermal oxidation of Ni onβ-Ga_(2)O_(3)to form NiO/β-Ga_(2)O_(3)p-n heterojunction diodes(HJDs).The NiO/β-Ga_(2)O_(3)HJDs exhibit excellent electrostatic properties,with a h... The 10 nm p-NiO thin film is prepared by thermal oxidation of Ni onβ-Ga_(2)O_(3)to form NiO/β-Ga_(2)O_(3)p-n heterojunction diodes(HJDs).The NiO/β-Ga_(2)O_(3)HJDs exhibit excellent electrostatic properties,with a high breakdown voltage of 465 V,a specific on-resistance(Ron,sp)of 3.39 mΩ·cm^(2),and a turn-on voltage(V on)of 1.85 V,yielding a static Baliga's figure of merit(FOM)of 256 MW/cm^(2).Also,the HJDs have a low turn-on voltage,which reduces conduction loss dramatically,and a rectification ratio of up to 108.Meanwhile,the HJDs'reverse leakage current is essentially unaffected at temperatures below 170?C,and their leakage level may be controlled below 10^(-10)A.This indicates that p-NiO/β-Ga_(2)O_(3)HJDs with good thermal stability and high-temperature operating ability can be a good option for high-performanceβ-Ga_(2)O_(3)power devices. 展开更多
关键词 NiO/β-Ga_(2)O_(3)p-n heterojunction diodes Baliga's figure of merit reverse leakage current β-Ga_(2)O_(3)power devices
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Controllable synthesis of a self-assembled ultralow Ru,Ni-doped Fe_(2)O_(3) lily as a bifunctional electrocatalyst for large-current-density alkaline seawater electrolysis 被引量:1
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作者 Tong Cui Xuejun Zhai +5 位作者 Lili Guo Jing-Qi Chi Yu Zhang Jiawei Zhu Xuemei Sun Lei Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2202-2211,共10页
Highly efficient and stable bifunctional electrocatalysts that can be used for large-current-density electrolysis of alkaline seawater are highly desirable for carbon-neutral economies,but their facile and controllabl... Highly efficient and stable bifunctional electrocatalysts that can be used for large-current-density electrolysis of alkaline seawater are highly desirable for carbon-neutral economies,but their facile and controllable synthesis remains a challenge.Here,self-assembled ultralow Ru,Ni-doped Fe_(2)O_(3) with a lily shaped morphology was synthesized on iron foam(RuNi-Fe_(2)O_(3)/IF)via a facile one-step hydrothermal process,in which the intact lily shaped RuNi-Fe_(2)O_(3)/IF was obtained by adjusting the ratio of Ru/Ni.Benefitting from the Ru/Ni chemical substitution,the as-synthesized RuNi-Fe_(2)O_(3)/IF can act as free-standing dual-function electrodes that are applied to electrocatalysis for the hydrogen evolution(HER)and oxygen evolution reactions(OER)in 1.0 mol L^(-1) KOH,requiring an overpotential of 75.0 mV to drive 100 mA cm^(-2) for HER and 329.0 mV for OER.Moreover,the overall water splitting catalyzed by RuNi-Fe_(2)O_(3)/IF only demands ultralow cell voltages of 1.66 and 1.73 V to drive 100 mA cm^(-2) in 1.0 mol L^(-1) KOH and 1.0 mol L^(-1) KOH seawater electrolytes,respectively.The electrodes show remarkable long-term durability,maintaining current densities exceeding 100 mA cm^(-2) for more than 100 h and thus outperforming the two-electrode system composed of noble catalysts.This work provides an efficient,economical method to synthesize self-standing bifunctional electrodes for large-current-density alkaline seawater electrolysis,which is of significant importance for ecological protection and energy exploitation. 展开更多
关键词 RuNi-Fe_(2)O_(3)/IF Lily shape Bifunctional electrocatalyst Alkaline seawater splitting Large current density
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A, ■-Ω METHOD FOR 3-D EDDY CURRENT ANALYSIS
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作者 施展伟 赵兴华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第11期0-0,0-0+0-0+0,共7页
After the field equations and the snonumuoo conditions between the interfaces for 3D eddy current problems Under various gauges were discussed, it was pointed cut in this paper that using the magnetic vector potentia... After the field equations and the snonumuoo conditions between the interfaces for 3D eddy current problems Under various gauges were discussed, it was pointed cut in this paper that using the magnetic vector potential A. the electric scalar potential and Coulomb gauge △ .A = 0 in eddy current regions and using the magntetic scalar potential Ω in the non-conducting regions are more suitable. All field equations, the boundary conditions, the interface continuity conditions and the corresponding variational principle of this method are also given 展开更多
关键词 3-d eddy current field A method interface continuous conditions
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