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Journal of Mountain Science 2021年第9期18卷 2304-2314页

作者： ZHU Bei wang shi-yan SU Wei CHEN Kai-qi LIU Chang DU yan-liang wang Liang HAN Zhen ZOU Jiang-xiang State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Beijing 100038China China Institute of Water Resources and Hydropower Research Beijing 100038China College of Hebei Agricultural University Huanghua 061100China Appraisal Center for Environment and Engineering Ministry of Environmental ProtectionBeijing 100012China

As an important ecotone,the alpine timberline is the boundary between closed-canopy montane forest and alpine vegetation,and is highly sensitive to global and regional climate *** provided a way to identify and extract the alpine timberline in Yarlung Zangpo Grand Canyon Nature Reserve by using remote sensing data and spatial analysis based on land use/land cover classification and NDVI distribution *** DEM data,the influence of slope and aspect on the distribution of alpine timberline was *** results showed that the alpine timberline in Yarlung Zangpo Grand Canyon is transitional timberline,with the upper boundary approximately distributed at the elevation of 3422-4373 m,the lower boundary at approximately 3270-4164 m,with a width of about 110-280 *** timberline was mainly distributed on steep and very steep slopes ranging from 25°to 45°.The maximum elevation of both the upper and lower boundaries occurred on steep *** distribution of alpine timberline varies with aspects,with sunny slopes having a higher boundary than shady slopes.

关键词： Alpine timberline Aspect Normalized Difference Vegetation Index Remote sensing classification Slope

Synthesis and Crystal Structure of a New Mononuclear Copper(Ⅱ) Complex with 4,4′,6,6′-Tetrabromo-2,2′- [ethylenedioxybis(nitrilomethylidyne)]diphenol

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Chinese Journal of Structural Chemistry 2008年第2期27卷 183-186页

作者： XU Li ZHANG Yah-Ping wang Li shi Jun-yan DONG Wen-Kui School of Chemical and Biological Engineering Lanzhou Jiaotong University Lanzhou Gansu 730070 China

A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.

关键词： 4,4′,6,6′-tetrabromo-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol,copper(lI) complex synthesis crystal structure

Pulse-width compression based on photonic crystal fiber

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Optoelectronics Letters 2006年第3期2卷 206-208页

作者： wang Jing wang Zhen-li shi yan-mei Institute of Information Science and Engineering Ocean University of China Qingdao 266077 China

According to the characteristics of high-order solitons,compressed picosecond pulses are numerically simulated in the photonic crystal fiber (PCF),by means of split-step Fourier method. The results show that,PCF enables input pulse with lower peak power to form high-order solitons for the purpose of femtosecond pulse-width compression. For example,60- femtosecond pulse width was made for 1-ps initial pulse width only over the distance of 2.2 ***,shorter optimum fiber length for compression and higher compression ratio could be obtained on the premise of pre-chirp technique.

关键词：光纤通信脉冲宽带通信光学晶体纤维傅立叶算法

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舷间液舱模型声振耦合特性及声辐射控制

船舶力学 2019年第1期23卷 96-109页

作者：王世彦俞孟萨中国船舶科学研究中心江苏无锡214082

水下航行体内部设备产生的振动能量通过舷间液舱侧板和舱内水介质两个途径的耦合和传递,在外场产生辐射噪声,成为机械噪声控制的一个短板。文中以舷间液舱外场声辐射控制为背景,采用解析方法建立了液舱结构振动与内外声场的声振耦合模型... 详细信息

水下航行体内部设备产生的振动能量通过舷间液舱侧板和舱内水介质两个途径的耦合和传递,在外场产生辐射噪声,成为机械噪声控制的一个短板。文中以舷间液舱外场声辐射控制为背景,采用解析方法建立了液舱结构振动与内外声场的声振耦合模型,计算分析了液舱侧板及液舱内部介质对振动传递和外场声辐射的影响,结果认为敷设声学覆盖层并减小液舱侧板材料刚度能够有效控制外场辐射声功率。文章为舷间液舱的"声短路"控制提供了新的思路。

关键词：平板加肋结构声振耦合液舱

Unilateral sacrospinous ligament fixation for treatment of genital prolapse

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Chinese Medical Journal 2010年第15期123卷 1995-1998页

作者： PENG Ping ZHU Lan LANG Jing-he wang Wen-yan shi Hong-hui Department of Obstetrics and Gynecology Peking Union College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China

Background Genital prolapse affects 30% of middle-aged and older women and is becoming a major public health concern. Sacrospinous ligament fixation is an effective and safe procedure for vaginal vault prolaps with a low recurrence and complication rate. This study aimed to investigate the efficacy and safety of unilateral sacrospinous ligament fixation （SSLF） for the management of pelvic organ prolapse （POP）.Methods Forty patients with severe prolapse of pelvic organ undergoing unilateral SSLF were retrospectively *** this study, all patients were staged by the value of POP-Q. All procedures were performed by a senior physician. The characteristics of these patients and their immediate and short-term post-operative outcome were recorded. All patients were seen six weeks and six months after the surgery. The evaluation included standardized questionnaire and site-specific vaginal examination by one *** The average operation time was 65-92 minutes. The average blood loss was 83-188 ml. The average hospitalization time was 6.1 days. The average cost was 5885 yuan. The average day of urethral catheter removal after the operation was 2.1 days. The incidence of postoperative morbidity was 17.1%. One （2.4%） patient had hematoma in the right pelvic. The mean length of postoperative follow-up for 35 patients was 13.1 months. The rate of follow-up was 87.5%. One （2.9%） patient showed recurrent vaginal vault prolapse six months after the surgery. The objective success rate of pelvic organ prolapse was 85% （34/40）. There was significant difference between the POP-Q of Aa, Ba, Ap, Bp,and D before and after operation （P 〈0.001 ）. Five （14.3%） patients complained lower back pain, gluteal pain or right groin pain. Three （8.6%） patients developed de novo stress incontinence. Vaginal disabsorbable sutures were found in three （8.6%） patients. One （2.9%） patient had de novo urge *** Unilateral SSLF was both cost and treatment effective managem

关键词： unilateral sacrospinous ligament fixation genital prolapse complication

STUDIES ON THE SYNTHESIS OF CEMBRANOLIDESⅠ.THE SYNTHESIS OF A KEY INTERMEDIATE(E,E,E,E)-2,6,10,14-TETRAMETHYL-8-BENZENESULFONYL-2,6,10,14-TETRAEN-1,16-HEXADECADIOL

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Chinese Chemical Letters 1993年第8期4卷 659-660页

作者： Bi GAO Qi Huang ZHENG Zhi Cai wang shi yan FAN Department of Chemistry,Zhongshan University,Guangzhou,510275

A key intermediate of cembranolides--(E,E,E,E)- 2,6,10,14- tetramethyl- 8-benzenesulfonyl- 2,6,10,14- tetraen-1,16- hexadecadiol was synthesized from geraniol and linalool through six steps.

关键词： E,E,E,E THE SYNTHESIS OF A KEY INTERMEDIATE STUDIES ON THE SYNTHESIS OF CEMBRANOLIDES TETRAMETHYL-8-BENZENESULFONYL-2,6,10,14-TETRAEN-1,16-HEXADECADIOL

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聚合物阻垢机理的分子动力学模拟研究

中国石油大学学报（自然科学版） 2007年第5期31卷 144-147页

作者：王世燕张军卢贵武中国石油大学物理科学与技术学院山东东营257061 中国石油大学数理系北京102249

为了研究聚羧酸类阻垢剂分子的阻垢性能,采用分子动力学方法模拟了方解石(110)晶面加入聚丙基-丙烯酸甲酯(PPA)分子后晶面与CO32-和Ca2+的相互作用。计算结果表明,加入PPA后方解石晶面对游离态CO32-和Ca2+离子结合能明显小于加入PPA前,... 详细信息

为了研究聚羧酸类阻垢剂分子的阻垢性能,采用分子动力学方法模拟了方解石(110)晶面加入聚丙基-丙烯酸甲酯(PPA)分子后晶面与CO32-和Ca2+的相互作用。计算结果表明,加入PPA后方解石晶面对游离态CO32-和Ca2+离子结合能明显小于加入PPA前,说明PPA分子阻止了CO32-和Ca2+在方解石晶面的吸附。同时,对两种体系下CO32-离子的动力学行为的分析结果也证明了PPA的阻垢能力。相互作用后PPA分子发生了一定的形变,并且其中部链基变化比两端大,说明中部链基的阻垢能力比较强。

关键词：分子动力学方解石阻垢剂吸附能

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li yan wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

Revealing and predicting the long-term biomechanical response of orthokeratology by developing a patient-specific computational model

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 156-168页

作者： Yifeng Li Zhuoran yang Ziming yan Huibin shi Zhanli Liu Kaijie wang Department of Engineering Mechanics School of Aerospace Engineering Tsinghua University Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Lab

Orthokeratology(OK) is widely used for effective myopia correction and control. However, the incomplete understanding of its biomechanical mechanisms makes OK lens fitting rely heavily on clinician judgment, complicating accurate predictions of treatment outcomes. In this paper, we performed clinical experiments and numerical analysis to study corneal deformation modes and long-term changes in central corneal thickness. Clinical experiments were conducted on 194 Chinese myopic patients under OK treatment for 3 months. Based on the experimental data, a patient-specific computational biomechanical model for OK was established and validated. Specifically, the anisotropic mechanical properties of the cornea were incorporated into the model to describe the significant difference between its shear modulus(29.5 kPa) and tensile modulus(768.4 kPa). Additionally, a viscohyperelastic material model with a prolonged corneal relaxation time of 5.6 h was developed to capture the long-term deformation response. The results show that corneal thickness reduction in OK is primarily due to out-of-plane shear deformation,influenced by the cornea's low shear resistance. Modeling the extended corneal relaxation time is crucial for predicting long-term biomechanical responses. The computational model effectively captures long-term changes in central corneal thickness, potentially improving OK lens fitting accuracy.

关键词： orthokeratology computational biomechanical model long-term viscoelasticity myopia correction

基于全变分的运动分割模型及分裂Bregman算法

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自动化学报 2015年第2期41卷 396-404页

作者：王诗言于慧敏重庆邮电大学重庆400065 浙江大学信息与电子工程学系杭州310027

提出了一种基于全变分的运动分割模型,可以适用于2D/3D视频.首先,通过活动轮廓模型将分割与估计融合在同一能量函数中,该模型能够同时进行分割曲面的演化和运动参数的估计.其次,通过凸松弛方法将原始问题转化为等价的全变分模型,克服了... 详细信息

提出了一种基于全变分的运动分割模型,可以适用于2D/3D视频.首先,通过活动轮廓模型将分割与估计融合在同一能量函数中,该模型能够同时进行分割曲面的演化和运动参数的估计.其次,通过凸松弛方法将原始问题转化为等价的全变分模型,克服了局部最小值问题.最后,采用分裂Bregman快速算法进行求解.多组实验证明了本文方法对2D/3D视频的通用性和算法的高效性.

关键词：运动分割运动估计全变分分裂Bregman算法