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电子技术（上海） 2024年第1期53卷 74-75页

作者：李午阳匡迎春胡超沈岳湖南农业大学信息与智能科学技术学院湖南410128

阐述校园中的教学、管理、安全问题原因,提出基于人工智能、数字孪生技术的数字孪生校园建设方案,分析新型智慧课堂、智慧安防的应用方案,从而实现教学及管理的升级。

关键词：智慧校园数字孪生智慧课堂智慧安防

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静脉腔内热消融术治疗下肢静脉曲张研究进展

中国医学装备 2024年第8期21卷 176-181页

作者：杨纯旭张玥匡英杰刘效敏山东中医药大学第一临床医学院济南250014 山东中医药大学附属医院周围血管病科济南250014 山东中医药大学附属医院运动损伤骨科济南250014

下肢静脉曲张在静脉系统疾病中的发病率较高,手术治疗是下肢静脉曲张的主要治疗方式。随着医学技术的进步和微创理念的发展,静脉腔内热消融术(EVTA)以其创伤小、术后恢复快、并发症发生率低、闭合率高等特点,成为下肢静脉曲张治疗指南... 详细信息

下肢静脉曲张在静脉系统疾病中的发病率较高,手术治疗是下肢静脉曲张的主要治疗方式。随着医学技术的进步和微创理念的发展,静脉腔内热消融术(EVTA)以其创伤小、术后恢复快、并发症发生率低、闭合率高等特点,成为下肢静脉曲张治疗指南中的首选推荐术式。EVTA主要包括腔内射频消融术(RFA)、腔内激光消融术(EVLA)和腔内微波消融术(EMA),通过不同的热消融设备施加热量于目标血管,以热能破坏血管内皮细胞和管壁胶原纤维,使管腔收缩形成纤维条索,从而达到闭合目标血管的目的。不同的EVTA术式作用机制、治疗效果以及并发症发生率不同,在应用范围上也有所区别。综述EVTA常见术式及近5年的临床应用,为合理选择热消融术式及设备提供参考,为预防热损伤并发症提供帮助。

关键词：下肢静脉曲张静脉腔内热消融术(EVTA) 腔内射频消融术(RFA) 腔内激光消融术(EVLA) 腔内微波消融术热损伤

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新型可回收氮化硼/环氧树脂复合材料导热与介电性能研究

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绝缘材料 2024年第5期57卷 10-19页

作者：冯宇匡冠霖岳东 Victor O.Belko Sergey A.Maksimenko 杨洲哈尔滨理工大学电气与电子工程学院黑龙江哈尔滨150080 圣彼得堡彼得大帝理工大学高电压工程学院俄罗斯圣彼得堡859111 白俄罗斯国立大学核问题研究所白俄罗斯明斯克220030 哈尔滨大电机研究所黑龙江哈尔滨150040

热固性环氧树脂因具有优异的导热性能与绝缘性能在电工装备领域得到广泛应用,由于其具有稳定的三维网络结构和不溶性,回收再利用存在挑战性。本文将不同质量分数的氮化硼(BN)加入到环氧(EP)/4-甲基六氢苯酐降解体系中,制备出高导热、高... 详细信息

热固性环氧树脂因具有优异的导热性能与绝缘性能在电工装备领域得到广泛应用,由于其具有稳定的三维网络结构和不溶性,回收再利用存在挑战性。本文将不同质量分数的氮化硼(BN)加入到环氧(EP)/4-甲基六氢苯酐降解体系中,制备出高导热、高绝缘、可降解型BN/EP复合材料,并对BN/EP复合材料的导热性能、介电性能以及可降解性能进行研究。结果表明:以2,4,6-三(二甲氨基甲基)苯酚作为催化剂,在乙二醇作用下该BN/EP复合材料可在200℃下实现常压降解。BN质量分数为15%的BN/EP复合材料热导率为0.335 W/(m·K),比纯EP树脂提高了34%;交流电气强度为101.7 kV/mm,比纯EP树脂提高了13%。BN/EP复合材料可经酯交换降解得到EP降解产物(EDP),与EDP复合后,BN/EP复合材料的导热性能和电气强度基本保持不变。

关键词：环氧基复合材料降解回收热导率介电性能酯交换

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低墩盖梁培土施工技法总结

工程与建设 2021年第6期35卷 1299-1300页

作者：杨槐蒋权韩殿宾况月超王小强中国建筑第七工程局有限公司河南郑州450004

文章通过曲靖三宝至昆明清水高速公路(曲靖段)项目越州屯特大桥37#墩、38#墩盖梁施工,介绍了低墩盖梁培土法施工过程中重要工序需考虑的各个因素,总结了培土法施工工艺中的技术和工法,为以后低墩盖梁无支架施工提供一种借鉴的方法。

关键词：盖梁培土无支架

Tidal Asymmetry Changes in a Shallow Mud Estuary by a Restoration Project

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Journal of Ocean University of China 2019年第2期18卷 339-348页

作者： LIANG Huidi kuang Cuiping GU Jie MA yue CHEN Kuo LIU Xu College of Civil Engineering Tongji University College of Marine Ecology and Environment Shanghai Ocean University

The tidal asymmetry-induced siltation below tidal barriers is a worldwide problem that restricts regional socio-economic and environmental development. The hydrodynamic processes of the small mud estuary also feature a high uncertainty after estuary restoration measures. In this study, a hydrodynamic model based on the MIKE21 is used to quantify the responses of tidal asymmetry to a two-phase restoration project in Shuanglong Estuary, Bohai Bay, China. According to the numerical modeling results, the tidal flat removal in the upper estuary(first-phase restoration) induces the flood asymmetry switching to the ebb asymmetry in unrestored reach but enhances flood asymmetry in widening restored reach. Although the tidal asymmetry reverts to flood-dominated pattern after full restoration over the estuary, the imbalance between flood and ebb velocities is relieved. A possible net sediment transport pattern based on a comparison of dominant asymmetric current and actual sediment transport period shows net sediments in the upper estuary and inlet transport seaward and landward, respectively, in the first-phase restoration, whereas landward net sediment transport occurs in the whole estuary under the second-phase restoration scenario. Given these results, we assume that a switch from the flood-dominated estuary to ebb-dominated estuary can be caused by redesigning the cross-sectional profile. The quantitative comparison of Lagrangian residual currents also implies that a channel–shoal structure rather than a flat bathymetry can promote the mass transport. Therefore, reshaping the channel–tidal flat system in restoration projects can prevent the sedimentation of the estuary and improve the water environment.

关键词： tidal asymmetry restoration project mud estuary net sediment transport

TOP QUARK MASS AND THE FOURTH GENERATION OF QUARK

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Chinese Physics Letters 1984年第2期1卷 47-48页

作者： CHOU kuang-chao WU yue-liang XIE Yan-bo Institute of Theoretical Physics Academia SinicaBeijing

To explain CP violation in Kaon system in the light of the recently measured b - lifetime within the framework of three generations of quarks, the top quark mass has to be greater than 50GeV if the current algebra value of the factor BK is adopted and | ε’/ε|< 0.01. In this letter a fourth generation of quark is considered which can fit the present experimental data on CP violation, and KL→ μ ^(+) μ^(- )decay rate for top quark mass is around 40GeV. The mass of the new charge 2/3 quark is predicted to be over 100Gev.

关键词： quark algebra letter

Insignin A, A Novel C_21-Steroidal Aglycone from Biondia insignis

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Chinese Chemical Letters 2000年第12期11卷 1065-1068页

作者： Yuan Hu ZHANG yue Mao SHEN Yuan Ying WEN Ting Yun kuang Laboratory of Phytochemistry and Department of Plant Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Laboratory of Phytochemistry Institute of BotanyChinese Academy of SciencesBeijing 100093

Insignin A, a new C21-steroidal aglycone having the rare 15,16-seco pregnane skeleton was isolated from the acidic hydrolysis part of the 95% EtOH extract of Biondia insignis. It's structure was identified to be 15R,... 详细信息

关键词： Asclepiadaceae Biondia insignis C21-steroidal aglycone insignin A<

蛇含委陵菜的木脂素类成分及其细胞毒活性研究

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广西植物 2024年第6期44卷 1082-1090页

作者：张宝杨红匡维米陈婷婷金倩倩李勇军李悦贵阳市妇幼保健院/贵阳市儿童医院药学部贵阳550003 贵州医科大学妇幼临床学院贵阳550003 贵州医科大学贵州省药物制剂重点实验室贵州贵安561113 贵州医科大学药学院贵州贵安561113

为了研究蛇含委陵菜(Potentilla kleiniana)的化学成分及其肿瘤细胞毒活性,该研究综合运用D-101大孔树脂、硅胶、Sephadex LH-20、Toyopearl HW-40F及半制备高效液相等现代色谱分离技术对蛇含委陵菜60%乙醇提取物进行分离纯化,根据化合... 详细信息

为了研究蛇含委陵菜(Potentilla kleiniana)的化学成分及其肿瘤细胞毒活性,该研究综合运用D-101大孔树脂、硅胶、Sephadex LH-20、Toyopearl HW-40F及半制备高效液相等现代色谱分离技术对蛇含委陵菜60%乙醇提取物进行分离纯化,根据化合物的理化性质结合核磁共振波谱(NMR)、高分辨质谱(HR-ESI-MS)鉴定化合物的结构,并采用MTT法测定各化合物对人宫颈癌细胞株Hela的细胞毒活性。结果表明:(1)从蛇含委陵菜中分离鉴定了13个木脂素类化合物,分别为(+)-松脂素(1)、(+)-8-羟基松脂素(2)、(+)-丁香脂素(3)、(+)-杜仲树脂酚(4)、(+)-松脂素-4-O-β-D-吡喃葡萄糖苷(5)、(+)-8′-羟基松脂素-4-O-β-D-吡喃葡萄糖苷(6)、(+)-8′-羟基松脂素-4′-O-β-D-吡喃葡萄糖苷(7)、(+)-松脂素-8′-O-β-D-吡喃葡萄糖苷(8)、schilignan F(9)、(+)-松脂素-4,4′-O-双吡喃葡萄糖苷(10)、(+)-落叶松脂素-4′-O-β-D-吡喃葡萄糖苷(11)、neoolivil-4-O-β-D-glucopyranoside(12)、3,3′-bis[3,4-dihydro-4-hydroxy-6-methoxy-2 H-1-benzopyran](13)。其中,化合物1-4、7、8、10、12、13为首次从委陵菜属植物中分离得到,化合物5、6、9、11为首次从蛇含委陵菜中分离得到。(2)细胞毒试验结果显示,化合物1、3、4对Hela细胞具有较好的抑制活性,其半数抑制浓度IC_(50)值分别为(69.94±1.89)、(66.25±2.11)、(59.81±1.73)μmol·L-1。该研究结果进一步丰富了蛇含委陵菜的化学成分,为抗宫颈癌药物的研发提供物质基础。

关键词：蛇含委陵菜化学成分分离纯化结构鉴定木脂素细胞毒性抗肿瘤活性

Effect of spatial spectrum overlap on Fourier ptychographic microscopy

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Journal of Innovative Optical Health Sciences 2017年第2期10卷 11-22页

作者： Qiulan Liu Cuifang kuang yue Fang Peng Xiu Yicheng Li Ruixin Wen Xu Linu State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang University Hangzhou 310027 P.R.China Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan030006P.R.China

Fourier ptychographic microscopy(FPM)is a newly developed imaging technique which stands out by virtue of its high-resolution and wide *** improves a microscope's imaging perfor-mance beyond the diffraction limit of the employed optical components by illuminating the sample with oblique waves of different incident angles,similar to the concept of synthetic *** propose to use an objective lens with high-NA to generate oblique illuminating waves in *** demonstrate utilizing an objective lens with higher NA to iluminate the sample leads to better resolution by simulations,in which a resolution of 0.28 pum is achieved by using a high-NA illuminating objective lens(NA=1.49)and a low-NA collecting objective lens(NA=0.2)in coherent imaging(λ=488 nm).We then deeply study FPM's exact relevance of convergence speed to spatial spectrum overlap in frequency *** simulation results show that an overlap of about 60%is the optimal choice to acquire a high-quality recovery(520*520 pixels)with about 2 min's computing *** addition,we testify the robustness of the algorithm of FPM to additive noises and its suitability for phase objects,which further proves FPM's potential application in biomedical imaging.

关键词： Fourier ptychographic microscopy synthetic aperture convergence speed spatial spectrum overlap.

Influence of Headland Breakwaters on Morphological Processes at Longfengtou Beach in Haitan Bay,Facing the Taiwan Strait

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Journal of Ocean University of China 2018年第6期17卷 1290-1300页

作者： kuang Cuiping MA yue WANG Binyu SUI Jueyi GU Jie LIU Jianhui LEI Gang College of Civil Engineering Tongji UniversityShanghai 200092China Guangxi Vocational and Technical College of Communications Nanning 530216China Environmental Engineering Program University of Northern British ColumbiaPrince GeorgeBC V2N4Z9Canada College of Marine Ecology and Environment Shanghai Ocean UniversityShanghai 201306China Island Research Center PingtanFujian 350400China Third Institute of Oceanography State Oceanic AdministrationFujian 361005China

Breakwaters can be used as artificial headlands in beach nourishment to mitigate coastal erosion. Longfengtou Beach, located on the southwest coast of Haitan Bay facing the Taiwan Strait on the northeast, suffers severe erosion, where the monsoon causes significant season hydrodynamic variations. Headland breakwaters are intended to be employed to mitigate coastal erosion. A 2D sediment transport model is established using MIKE21 based on current-wave coupling and calibrated by measured data. Summer and winter wave conditions are chosen as characteristic weak and strong waves respectively. The numerical results of suspended sediment concentration and seasonal morphological evolution are compared under the conditions with and without the headland breakwaters. Sediment transport in summer can be regarded as mainly determined by current field, while in winter wave effect is strong enough to change current field. The northern breakwater, nearly perpendicular to the ebb current direction, obstructs the currents and decreases velocity of the ebb currents, and confines the water carrying sediments within the protection area during the flood period. The southern breakwater also breaks the waves in advance and significantly reduces the hydrodynamic effects during the flood period and maintains high suspended sediment concentration in the protection area. In general, two headland breakwaters decrease the erosion near the beach and enlarge the deposition area, which play a significant role in prevention of sediment loss in nearshore area and mitigate coastal erosion.

关键词： headland breakwater Haitan Bay sediment transport morphological evolution