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完全腹腔镜下规则性左肝切除术治疗左肝胆管结石的临床研究

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中华普外科手术学杂志（电子版） 2018年第5期12卷 448-450页

作者：贺德龙周为薛长梅杨录青海省湟中县第二人民医院外科西宁811601 青海大学附属医院肝胆胃肠外科西宁810001

目的探讨完全腹腔镜下规则性左肝切除术治疗左肝胆管结石的临床疗效。方法回顾性分析2013年8月至2017年2月收治的45例左肝胆管结石患者的临床资料,分别为腹腔镜组(21例)和开腹组(24例),采用SPSS 18.0软件进行统计学分析,围术期相关指标... 详细信息

目的探讨完全腹腔镜下规则性左肝切除术治疗左肝胆管结石的临床疗效。方法回顾性分析2013年8月至2017年2月收治的45例左肝胆管结石患者的临床资料,分别为腹腔镜组(21例)和开腹组(24例),采用SPSS 18.0软件进行统计学分析,围术期相关指标和肝功能指标等以(x±s)表示,采用独立样本t检验;术后白蛋白使用率、术中输血率、术后止痛药使用率、并发症发生率、结石清除率及复发率等组间比较采用χ2检验,P0.05)。结论完全腹腔镜下规则性左肝切除术治疗左肝胆管结石是安全可行的,具有创伤小、疼痛轻、恢复快的优势,值得在临床推广应用。

关键词：胆结石腹腔镜检查肝切除术

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气流辅助的静电纺丝技术研究进展

纺织学报 2024年第8期45卷 44-53页

作者：刘德龙王红霞林童天津工业大学纺织科学与工程学院天津300387

近年来,通过引入外部气流来增强静电纺使纳米纤维生产能力取得了显著进展,气流辅助不仅提高了静电纺丝效率,还改善了纤维的取向、堆积密度甚至形貌,已逐渐发展成为一种先进的纳米纤维制造方法。不同的气流施加方式,对静电纺丝过程具有... 详细信息

近年来,通过引入外部气流来增强静电纺使纳米纤维生产能力取得了显著进展,气流辅助不仅提高了静电纺丝效率,还改善了纤维的取向、堆积密度甚至形貌,已逐渐发展成为一种先进的纳米纤维制造方法。不同的气流施加方式,对静电纺丝过程具有不同的效果,结合不同的静电纺丝模式,使其展示独特优势,从而极大地丰富了静电纺丝技术。综述了气流辅助静电纺丝技术的研究进展,包括其基本原理、发展历程,讨论了具有代表性的气流辅助静电纺丝装置,如气流辅助的针型静电纺丝、气流辅助的无针静电纺丝、离心静电纺丝主要参数和理论模拟。对气流辅助静电纺丝技术存在的问题以及未来研究发展进行了展望。

关键词：气流辅助静电纺丝纳米纤维生产率纺丝头

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稀土元素镧对锌阳极带电化学性能的影响

中国稀土学报 2003年第6期21卷 657-659页

作者：侯德龙宋月清何德山李德富王永蔡恒茂北京有色金属研究总院加工中心北京100088

研究了镧的加入对牺牲锌阳极带电化学性能的影响。结果表明,稀土元素镧对锌阳极带的电位和电流效率影响很小,实验结果符合相关标准。证明在纯锌中添加微量稀土元素镧改善锌阳极带机械性能,同时保持必要的电化学性能的工艺方法是有效、... 详细信息

研究了镧的加入对牺牲锌阳极带电化学性能的影响。结果表明,稀土元素镧对锌阳极带的电位和电流效率影响很小,实验结果符合相关标准。证明在纯锌中添加微量稀土元素镧改善锌阳极带机械性能,同时保持必要的电化学性能的工艺方法是有效、可行的。

关键词：电化学性能锌阳极带稀土元素镧电位电流效率电化学保护

宽视场条件下红黑树中心局域化加速的星图匹配技术

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光学学报 2024年第12期44卷 206-216页

作者：刘德龙杨文波柳鸣孙建南中国科学院国家天文台长春人造卫星观测站光电观测研究室吉林长春130117

较宽视场的星图匹配往往存在数据量巨大、边缘效应明显等问题进而影响计算的速度和精度。本文采用放大中心视场并优先处理的思想进行程序加速,并采用三次底片常数拟合匹配数据,减小宽视场观测中边缘视场处目标的定位误差。在实际的算法... 详细信息

较宽视场的星图匹配往往存在数据量巨大、边缘效应明显等问题进而影响计算的速度和精度。本文采用放大中心视场并优先处理的思想进行程序加速,并采用三次底片常数拟合匹配数据,减小宽视场观测中边缘视场处目标的定位误差。在实际的算法实现中,采用了基于红黑树的动态数据结构适配于中心视场的扩大;并应用GeoHash编码技术进行全域星象匹配。实验结果显示:三角形的匹配时间相较于原始算法减少了70.68%;在计算准确性上与系统原装软件的误差在亚像素水平;激光星轨道关联实验显示,关联差均在20″以内。长达一个月的实测结果表明,本文提出方法成功匹配了多达65万帧图像,识别准确率超过90%,平均每个观测夜识别到的目标达到580个。

关键词：星图匹配天文定位 GeoHash编码红黑树宽视场

Large-scale thrusting at the northern Junggar Basin since Cretaceous and its implications for the rejuvenation of the Central Asian Orogenic Belt

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Geoscience Frontiers 2015年第2期6卷 227-246页

作者： Jieyun Tang Dengfa he Di Li delong Ma The Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism The Ministry of EducationChina University of Geosciences (Beijing) Liaohe Oilfield Company China National Petroleum Corporation

The Wulungu Depression is the northernmost first-order tectonic unit in the Junggar Basin. It can be divided into three sub-units： the Hongyan step-fault zone, the Suosuoquan sag and the Wulungu south slope. The Cenozoic strata in the basin are intact and Mesozoic-Cenozoic deformation can be observed in the Wulungu step-fault zone, so this is an ideal place to study the Mesozoic-Cenozoic deformation. By integration of fault-related folding theories, regional geology and drilling data, the strata of the Cretaceous-Paleogene systems are divided into small layers which are selected as the subjects of this research. The combination of the developing unconformity with existing growth strata makes it conceivable that faults on the step-fault zone have experienced different degrees of reactivation of movement since the Cretaceous. Evolutionary analyses of the small layers using 2D-Move software showed certain differences in the reactivation of different segments of the Wulungu Depression such as the timing of reactivation of thrusting, for which the reactivity time of the eastern segment was late compared with those of the western and middle segments. In addition the resurrection strength was similarly slightly different, with the shortening rate being higher in the western segment than in the other segments. Moreover, the thrust fault mechanism is basement-involved combined with triangle shear fold, for which a forward evolution model was proposed.

关键词： Mesozoic-Cenozoic Thrust reactivity Wulungu depression Central Asian Orogenic Belt (CAOB)

Dynamic propagation velocity of a positive streamer in a 3 m air gap under lightning impulse voltage

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Plasma Science and Technology 2024年第4期26卷 114-121页

作者：李志伟雷挺苏宇姚修远杨冰雪刘德龙律方成丁玉剑 North China Electric Power University Beijing 102206People’s Republic of China China Electric Power Research Institute Beijing 100192People’s Republic of China

Streamers represent an important stage in the initiation of gap discharge. In this work, we used an eight-frame intensified charge-coupled device camera to capture the streamer development process when a lightning impulse voltage of 95%–100% U50% was applied in a 3 m rod–plate gap and the streamer velocity was analyzed. Analysis of the observations shows that streamer velocity can be defined by three stages: rapid velocity decline(stage 1), rapid velocity rise(stage 2)and slow velocity decline(stage 3). The effects of electrode shape, applied voltage and gap breakdown or withstanding on streamer velocity were analyzed. The electrode with a larger radius of curvature will result in a higher initial velocity, and a higher voltage amplitude will cause the streamer to propagate faster at stage 3. Gap withstanding or breakdown has no obvious effect on streamer velocity. In addition, the experimental results are compared with previous results and the statistical characteristics of the primary streamer discharge are discussed.

关键词： lightning impulse 3 m air gap development process streamer velocity

Mechanical Properties and Thermal Shock Resistance of SrAl_(2)Si_(2)O_(8) Reinforced BN Ceramic Composites

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无机材料学报 2024年第10期39卷 1182-1188页

作者： WANG Bo CAI delong ZHU Qishuai LI Daxin YANG Zhihua DUAN Xiaoming LI Yanan WANG Xuan JIA Dechang ZHOU Yu International Joint Laboratory of Advanced Nanomaterials of heilongjiang Province College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Key Laboratory of Advanced Structural-Functional Integration Materials School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China China Resources Cement Technology R&D Co. LtdGuangzhou 510000China The First Military Representative Office of the Army Equipment Department in Beijing Beijing 100072China The Fourth System Design Department Fourth AcademyChina Aerospace Science and Industry Corporation LimitedBeijing 100048China School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

hexagonal boron nitride(h-BN)ceramics have become exceptional materials for heat-resistant components in hypersonic vehicles,owing to their superior thermal stability and excellent dielectric ***,their densification during sintering still poses challenges for researchers,and their mechanical properties are rather *** this study,SrAl_(2)Si_(2)O_(8)(SAS),with low melting point and high strength,was introduced into the h-BN ceramics to facilitate the sintering and reinforce the strength and ***,BN-SAS ceramic composites were fabricated via hot press sintering using h-BN,SrCO_(3),Al_(2)O_(3),and SiO_(2) as raw materials,and effects of sintering pressure on their microstructure,mechanical property,and thermal property were *** thermal shock resistance of BN-SAS ceramic composites was *** show that phases of as-preparedBN-SAS ceramic composites are h-BN and h-SrAl_(2)Si_(2)O_(8).With the increase of sintering pressure,the composites’densities increase,and the mechanical properties shew a rising trend followed by a slight *** a sintering pressure of 20 MPa,their bending strength and fracture toughness are(138±4)MPa and(1.84±0.05)MPa·m^(1/2),*** sintered at 10 MPa exhibit a low coefficient of thermal expansion,with an average of 2.96×10^(-6) K^(-1) in the temperature range from 200 to 1200℃.The BN-SAS ceramic composites prepared at 20 MPa display higher thermal conductivity from 12.42 to 28.42 W·m^(-1)·K^(-1) within the temperature range from room temperature to 1000℃.Notably,BN-SAS composites exhibit remarkable thermal shock resistance,with residual bending strength peaking and subsequently declining sharply under a thermal shock temperature difference ranging from 600 to 1400℃.The maximum residual bending strength is recorded at a temperature difference of 800℃,with a residual strength retention rate of 101%.As the thermal shock temperature difference increase,the degree of oxida

关键词： BN matrix composite hot-press sintering mechanical property thermal shock resistance service reliability

从现实观察到设计生成——天津大学建筑学二年级的渐进式教学探索

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建筑学报 2024年第3期 14-19页

作者：孙德龙朱蕾张昕楠天津大学建筑学院天津300072

天津大学建筑学本科二年级的教学实践重在引导学生将现实观察与设计过程紧密结合,从具体教学中如何进行议题之间的衔接、议题与任务的衔接、观察方法与设计方法的衔接、观察分析工具与设计工具的衔接4个层面展开讨论,以引导学生从场所... 详细信息

天津大学建筑学本科二年级的教学实践重在引导学生将现实观察与设计过程紧密结合,从具体教学中如何进行议题之间的衔接、议题与任务的衔接、观察方法与设计方法的衔接、观察分析工具与设计工具的衔接4个层面展开讨论,以引导学生从场所、行为、材料性/氛围的维度认识建筑的复杂性,养成创造性的思维习惯。

关键词：现实观察设计生成渐进式教学第一冲动类推式设计

联合PS-InSAR技术与多变量LSTM神经网络的高铁路基冻胀形变预测研究

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测绘通报 2024年第1期 58-64页

作者：李鑫魏冠军张德龙兰州交通大学测绘与地理信息学院甘肃兰州730070 地理国情监测技术应用国家地方联合工程研究中心甘肃兰州730070 甘肃省地理国情监测工程实验室甘肃兰州730070

针对传统形变监测及预测难以做到大范围监测和精准预测的问题,本文提出了联合PS-InSAR技术和多变量长短期记忆(M-LSTM)神经网络监测和预测高铁路基冻胀形变的方法。首先,该方法利用PS-InSAR技术获取路基冻胀空间分布特征;然后,使用皮尔... 详细信息

针对传统形变监测及预测难以做到大范围监测和精准预测的问题,本文提出了联合PS-InSAR技术和多变量长短期记忆(M-LSTM)神经网络监测和预测高铁路基冻胀形变的方法。首先,该方法利用PS-InSAR技术获取路基冻胀空间分布特征;然后,使用皮尔逊相关系数法优化出3种冻胀诱发因素,所得数据经预处理后组成训练数据;最后,引入LSTM构建智能化、多变量冻胀预测模型,精确地预测路基冻胀形变趋势。研究结果表明,PS-InSAR技术在大范围形变监测中具有可靠性,M-LSTM模型预测精度比传统神经网络模型更高,平均判定系数(R^(2))、平均绝对误差(MAE)和平均均方根误差(RMSE)分别为0.973、0.024 mm和0.035 mm,说明M-LSTM模型在高铁路基冻胀形变预测中具有较好的应用价值,同时也为路基冻胀形变预测提供了新思路。

关键词： PS-InSAR 多变量LSTM模型高铁路基冻胀形变预测