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外伤性直接颈动脉海绵窦瘘的血管内治疗:54例回顾性病例系列研究

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国际脑血管病杂志 2020年第8期28卷 605-612页

作者：杨振兴孙阳阳苏芳琴黄德俊李宗正宁夏医科大学总医院神经外科银川750004

目的:探讨血管内栓塞治疗外伤性颈内动脉海绵窦瘘(traumatic carotid-cavernous fistula, TCCF)的有效性和转归的影响因素。方法:纳入2009年1月至2019年11月期间在宁夏医科大学总医院神经外科接受血管内栓塞治疗的Barrow A型TCCF患者。... 详细信息

目的:探讨血管内栓塞治疗外伤性颈内动脉海绵窦瘘(traumatic carotid-cavernous fistula, TCCF)的有效性和转归的影响因素。方法:纳入2009年1月至2019年11月期间在宁夏医科大学总医院神经外科接受血管内栓塞治疗的Barrow A型TCCF患者。使用可解脱球囊或Onyx-18联合弹簧圈经动脉入路治疗。术后进行临床和影像学随访。复发定义为即刻完全栓塞的病灶,再次行全脑数字减影血管造影时发现原来的瘘口再次显影。临床痊愈定义为颅内血管杂音、搏动性突眼、球结膜充血水肿均消失、眼球各方向活动无障碍及视力下降恢复。应用多变量 logistic回归分析确定影响影像学复发和临床痊愈的独立危险因素。结果:共纳入54例Barrow A型TCCF患者。患者年龄(42.5±10.6)岁(范围28-70岁);男性36例(66.7%)。临床表现:眼部症状(突眼、结膜充血等)40例(74.1%),颅内血管杂音35例(64.8%),视觉障碍(视力下降、视野缺损)36例(66.7%),头痛32例(59.3%),外展神经麻痹15例(28.3%),鼻衄4例(9.1%)。眼上静脉引流47例(87.0%),岩上、下窦引流19例(35.2%),皮质静脉引流9例(16.7%)。Onyx-18联合弹簧圈治疗28例(51.9%),可解脱球囊治疗26例(48.1%)。47例(87.0%)术后即刻完全栓塞,其中4例球囊栓塞失败后改用Onyx-18联合弹簧圈均达到完全栓塞;7例(13.0%)达到次全栓塞。47例(87.0%)痊愈,4例症状较入院时好转,但视力未完全恢复(其中3例出现外展神经麻痹症状),2例出现轻度偏瘫,无死亡患者。术后随访时有5例(9.3%)复发,采用Onyx-18联合弹簧圈达到完全栓塞。多变量 logistic回归分析显示,次全栓塞是影响术后影像学复发的独立危险因素(优势比16.63,95%可信区间1.74-159.33;P=0.015),存在皮质静脉引流是影响术后临床痊愈的独立危险因素(优势比19.08,95%可信区间1.61-226.58;P=0.020)。结论:Onyx-18联合弹簧圈或可解脱球囊治疗TCCF安全有效。次全栓塞与影像学复发相关,存在皮质静脉引流是临床痊愈的独立影响因素。

关键词：颈动脉海绵窦瘘栓塞治疗性治疗结果

Nanoindentation analysis of TiN,TiAlN,and TiAlSiN coatings prepared by cathode ion plating

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Science China(Technological Sciences) 2015年第8期58卷 1360-1368页

作者： KONG dejun FU GuiZhong College of Mechanical Engineering Changzhou University Jiangsu Key Laboratory of Materials Surface Science and Technology Changzhou University

The TiN, TiA1N and TiA1SiN coatings were deposited on H13 hot-worked mold steel by cathodic arc ion plating （CAIP）. The morphologies, phase compositions, and nanoindcntation parameters, such as creep hardness, elastic modulus and plastic de- formation energy of the coatings were analyzed with field emission scanning electron microscopy （FESEM）, X-ray diffraction （XRD） and nanoindentation testing, respectively, and the test results were compared with equation describing the indentation model. The results show that the TiN, TiA1N and TiAISiN coating surfaces were dense and composed of TiN, TiN ＋ TiA1N, TiN ＋ Si3N4 ＋ TiAIN phases, respectively. There was no spalling or cracking on the indentation surface. The creep hardness of the TiN, TiA1N and TiAISiN coatings was 7.33, 13.5, and 15.2 GPa, respectively; the corresponding hardness measured by nanoindentation was 7.09, 15.6, and 21.7 GPa, respectively; and the corresponding elastic modulus was 201.93, 172.79, and 162.77 GPa, respectively. The contact depth and elastic modulus calculated by the indentation model were close to those of the test results, but the remaining indentation parameters showed discrepancies. The sequence of plastic deformation energy was TiN 〉 TiA1N〉TiAISiN.

关键词： TiN TiAIN and TiAISiN coatings nanoindentation creep hardness elasticity modulus plastic deformation energy

基于行驶特征区间划分的重型载货汽车实际道路能耗评价方法

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汽车工程学报 2024年第3期14卷 544-552页

作者：黄德军田茂军彭航冉林尧向橄张龙平中国汽车工程研究院股份有限公司重庆401122

提出一种基于行驶特征区间划分的能耗评价方法。通过对中国货车行驶工况的工况点分布特征进行分析,确定了速度和加速度区间的数量与边界的划分方案。考虑道路坡度的影响,进行实际道路试验数据筛选,并用于计算不同行驶特征区间内的燃油... 详细信息

提出一种基于行驶特征区间划分的能耗评价方法。通过对中国货车行驶工况的工况点分布特征进行分析,确定了速度和加速度区间的数量与边界的划分方案。考虑道路坡度的影响,进行实际道路试验数据筛选,并用于计算不同行驶特征区间内的燃油消耗量平均值。结合中国货车行驶工况在不同行驶特征区间内的累计行驶里程,计算能耗评价结果。为了验证该方法的有效性,开展了3次底盘测功机试验和2次实际道路行驶试验,结果表明,所提出的能耗评价方法能提高重型载货汽车实际道路能耗评价结果的复现性。

关键词：重型载货汽车实际道路能耗评价行驶特征道路坡度区间划分

The importance of proleptic branch traits in biomass production of poplar in high-density plantations

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Journal of Forestry Research 2022年第2期33卷 463-473页

作者： Changjun Ding Ningning Wang Qinjun huang Weixi Zhang Juan huang Suli Yan Boyi Chen dejun Liang Yufeng Dong Yingbai Shen Xiaohua Su State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijingPeople’s Republic of China Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of ForestryChinese Academy of ForestryBeijingPeople’s Republic of China College of Biological Sciences and Technology Beijing Forestry UniversityBeijing 100083People’s Republic of China National Engineering Laboratory for Tree Breeding Beijing Forestry UniversityBeijing 100083People’s Republic of China Liaoning Provincial Poplar Institute Gaizhou 115200LiaoningPeople’s Republic of China Shandong Provincial Key Laboratory of Forest Tree Genetic Improvement Shandong Academy of ForestryJinan 250014ShandongPeople’s Republic of China

Branch phenotypic traits determine tree crown architecture,which in turn governs leaf display,light interception,and biomass *** and proleptic branches are the obviously different branch phenotypes in the poplar *** studies have focused on the influence of sylleptic branch numbers(SBN)on biomass production,but the research on the influence of proleptic branch phenotypes was only a *** explore the relationship between proleptic branch traits and biomass generation production in a high-density poplar plantation,we investigated the branch phenotypic traits of three poplar genotypes,all of which have high survival rates in forests(>95%)and significantly different crown architecture and biomass performance in the high-density plantations(1667 stems ha−1).The plantation site was established in 2007.A terrestrial laser scanner was used to measure branch characteristics such as length,angle of origin and termination,and azi-muth angle.A hierarchical cluster analysis performed on branch characteristics showed that SBN,crown depth,and proleptic branch curvature(PBC)were clustered with bio-mass production and leaf area index(LAI).Among all of the monitored traits,PBC played the second most important role in biomass production after SBN and was significantly correlated with SBN,LAI,and biomass *** positive correlation between PBC and SBN indicated that a larger PBC was associated with more sylleptic branches within the monitored genotypes planted in the high-density plantation,providing greater leaf area and biomass *** results of this study will improve the identification of high-production poplar varieties for cultivation in high-density plantations for biofuel production.

关键词： Populous Crown architecture Sylleptic branch Proleptic branch Biomass production Terrestrial laser scanner

Gorenstein AC-Projective and AC-Injective Modules over Formal Triangular Matrix Rings

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Algebra Colloquium 2022年第3期29卷 475-490页

作者： dejun Wu Hui Zhou Department of Applied Mathematics Lanzhou University of Technology Lanzhou 730050China

Let A and B be rings and U a(B,A)-*** BU is flat and UA is finitely generated projective(resp.,BU is finitely generated projective and UA is flat),then the characterizations of level modules and Gorenstein AC-projective modules(resp.,absolutely clean modules and Gorenstein AC-injective modules)over the formal triangular matrix ring T=(A0 UB)are *** applications,it is proved that every Gorenstein AC-projective left T-module is projective if and only if each Gorenstein AC-projective left A-module and B-module is projective,and every Gorenstein AC-injective left T-module is injective if and only if each Gorenstein AC-injective left A-module and B-module is ***,Gorenstein AC-projective and AC-injective dimensions over the formal triangular matrix ring T are studied.

关键词： formal triangular matrix ring Gorenstein AC-projective module level module absolutely clean module

holder continuity of semigroups for ;ime changed symmetric stable processes

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Frontiers of Mathematics in China 2016年第1期11卷 109-121页

作者： dejun LUO Jian WANG Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of Mathematics and Computer Science Fujian Normal University Fuzhou 350007 China

Let （Zt）t≥o be a one-dimensional symmetric α-stable process with α ∈ （0, 2）, and let a be a bounded （from above and from below） and 1/（α V 1）- Holder continuous function on R. Consider the stochastic differential equation dXt = σ（Xt-）dZt, which admits a unique strong solution. By using the splitting technique and the coupling method, we derive the HSlder continuity of the associated semigroup.

关键词： Symmetric stable process time-change Holder continuity coupling

SIMPLIFIED MODEL AND ITS APPLICATION FOR WAVEMAKING INDUCED BY EXPLOSION

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Journal of Hydrodynamics 1995年第1期7卷 33-44页

作者： Shen, Guoguang Li, dejun Tianjin Univ Tianjin China

This paper pays attention to the analysis of overall macroscopic process of wavemaking induced by explosion. Based on establishing the simplified model and MAC method, the numerical simulations for formulating crater induced by touching water surface explosion, the bubble jumping out of the water surface induced by underwater explosion as well as hollow column formation for large equivalent explosion etc were carried out. In order to predict the wave field, the scheme simulated by falling and evoluting of an ″equivalent cylinder″ were proposed. In addition to researching the wavemaking response in a harbour, two joining methods in time domain were presented. The results indicate that the model and numerical methods are feasible.

关键词： Bubbles (in fluids) Computer simulation Explosion testing Mathematical models Surface waves

Numerical investigation of viscous fingering in Hele-Shaw cell with spatially periodic variation of depth

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Applied Mathematics and Mechanics(English Edition) 2016年第1期37卷 45-58页

作者： Jiangping HU Bofu WANG dejun SUN Department of Modern Mechanics University of Science and Technology of China School of Power and Mechanical Engineering Wuhan University

Viscous fingering in a modified Hele-Shaw cell is numerically investigated. The cell allows periodic variation of depth in the lateral direction. The wavenumber n of the depth perturbation has great influence on fingering patterns. For n = 1, the fingering pattern due to the interface instability remains the same as that in the conventional Hele- Shaw cell, while the depth variation causes the steady finger to be a little narrower. For n = 2, four different fingering patterns are captured, similar to the available experimental observations in a modified Hele-Shaw cell containing a centered step-like occlusion. It is found that new fingering patterns appear as n further increases, among which, two patterns with spatial oscillation along both edges of the finger are particularly interesting. One is a symmetric oscillatory finger for n = 3, and the other is an asymmetric one for n = 4. The influence of capillary number on fingering patterns is studied for n = 3 and 4. We find that spatial oscillation of the finger nearly ceases at moderate capillary numbers and occurs again as the capillary number increases further. Meanwhile, the wide finger shifts to the narrow one. It is accompanied by a sudden decrease in the finger width which otherwise decreases continuously as the capillary number increases. The wavenumber and the amplitude of depth perturbation have little effect on the finger width.

关键词： Hele-Shaw cell viscous fingering pattern formation interracial instability

边界条件对柴油机瞬态过程能量流及?流的影响规律研究

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汽车工程学报 2022年第2期12卷 154-161,169页

作者：朱红国黄德军伍晨波刘长铖杨泽宇田径中国汽车工程研究院股份有限公司重庆401122 吉林大学汽车仿真与控制国家重点实验室长春130025

在一台高压共轨增压中冷柴油机上,分析了负荷加载时间、冷却系统温度等边界条件对典型恒转速增转矩瞬变过程能量流及?流的影响规律。结果表明,柴油机负荷加载过程热效率和?效率总体呈现先上升后下降的趋势,且加载时间越短,进气迟滞引起... 详细信息

在一台高压共轨增压中冷柴油机上,分析了负荷加载时间、冷却系统温度等边界条件对典型恒转速增转矩瞬变过程能量流及?流的影响规律。结果表明,柴油机负荷加载过程热效率和?效率总体呈现先上升后下降的趋势,且加载时间越短,进气迟滞引起的能量劣变会导致更低的能量利用率;改变中冷器冷却特性,提高加载过程进气温度将导致缸内扩散燃烧份额增加、传热时间更长,而冷却液温度降低则不利于改善瞬态工况缸内等效绝热特征,导致传热和排气过程能量损失及其中的可用能份额增大;调制负荷加载时间和冷却系统温度有助于改善柴油机加载过程进气响应特性、缸内热氛围状态和绝热特征,提升柴油机瞬态工况能量利用水平。

关键词：增压柴油机瞬态工况边界参数能量流 ?流