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Synthesis and structure determination of pyrazine-containing macrocyclic polyazomethines

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Chinese Chemical Letters 2010年第10期21卷 1263-1266页

作者： Liang Chun Wu Long Qing Liu hai shan jin Ming Liang Ma Xiao Li Zhao Ke Wen Division of Supramolecular Chemistry and Medicinal Chemistry Key Laboratory of Brain Functional Genomics MOE and Shanghai Key Laboratory of Brain Functional Genomics East China Normal University Shanghai 200062 China shanghai Key Laboratory of Green Chemistry and Chemical Processes and Department of Chemistry East China Normal University Shanghai 200062 China

Two pyrazine-containing macrocyclic polyazomethines 2 and 3 were synthesized by direct [2 ＋ 2] and [3 ＋ 3] condensation reactions between 2,21-[pyrazine-2,3-diylbis（oxy）]dibenzaldehyde （1） and hydrazine. Both 2 ... 详细信息

关键词： Azomethine Macrocycles Schiff base Pyrazine

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基于高质量和低振动的铣削参数优化方法研究

机床与液压 2020年第6期48卷 91-98页

作者：周云峰王德超金山海朴成道延边大学工学院吉林延吉133002

针对数控铣床在切削过程中产生的振动对工件表面质量的影响,提出以低振动和高表面质量为优化目标,对切削参数进行优化。以VDF-850A铣床为研究对象对45号钢进行铣削正交试验,通过建立振动采集系统,采集振动信号提取振动特征值并测量工件... 详细信息

针对数控铣床在切削过程中产生的振动对工件表面质量的影响,提出以低振动和高表面质量为优化目标,对切削参数进行优化。以VDF-850A铣床为研究对象对45号钢进行铣削正交试验,通过建立振动采集系统,采集振动信号提取振动特征值并测量工件表面粗糙度值,应用最小二乘法拟合数据建立了振动和粗糙度数学模型。利用层次分析法确定两目标函数权重,使用平方和加权法对两目标函数加权拟合成综合目标评价函数,运用粒子群算法优化切削参数。试验结果表明:应用粒子群算法优化后的切削参数进行加工可有效的降低振动和提高表面质量。

关键词：切削振动表面粗糙度粒子群算法多目标铣削参数优化

Anatomic structural study of cerebellopontine angle via endoscope

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Chinese Medical Journal 2007年第20期120卷 1836-1839页

作者： XIA Yin LI Xi-ping HAN De-min ZHENG Jun LONG hai-shan SHI jin-feng Department of Otolaryngology,Beijing Tongren Hospital,Capital Medical University Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University),Ministry of Education,Beijing 100730,China (Xia Y,Li XP,Han DM,Zheng J,Long HS and Shi JF) Department of Otolaryngology Beijing Tongren Hospital Capital Medical University Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University) Ministry of Education Beijing 100730 China.

Background Minimally invasive surgery in skull base relying on searching for possible anatomic basis for endoscopic technology is controversial. The objective of this study was to observe the spatial relationships between main blood vessels and nerves in the cerebellopontine angle area and provide anatomic basis for lateral and posterior skull base minimally invasive surgery via endoscopic retrosigmoid keyhole approach.Methods This study was conducted on thirty dried adult skulls to measure the spatial relationships among the surface bony marks of posterior cranial fossa, and to locate the most appropriate drilling area for retrosigmoid keyhole approach. In addition, we used 10 formaldehyde-fixed adult cadaver specimens for simulating endoscopic retrosigmoid approach to determine the visible scope.Results The midpoint between the mastoid tip and the asterion was the best drilling point for retrosigmoid approach. A hole centered on this point with the 2.0 cm in diameter was suitable for exposing the related structures in the cerebellopontine angle. Retrosigmoid keyhole approach can decrease the pressure on the cerebellum and expose the related structures effectively which include facial nerve, vestibulocochlear nerve, trigeminal nerve, glossopharyngeal nerve, vagus nerve, accessory nerve, hypoglossal nerve, anterior inferior cerebellar artery, posterior inferior cerebellar artery and labyrinthine artery, etc.Conclusions Exact location on endoscope retrosigmoid approach can avoid dragging cerebellum during the minimally invasive surgery. The application of retrosigmoid keyhole approach will extend the application of endoscopic technology.

关键词： applied anatomy cerebellopontine angle endoscope operative approach

基于优质高效的数控铣削参数优化方法研究（英文）

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机床与液压 2019年第24期47卷 74-80页

作者：王德超周云峰朴成道金山海尹凤哲延边大学工学院吉林延吉133002 延边大学工程训练中心吉林延吉133002

为了实现模具制造过程的优质高效率生产,基于能量效率、表面质量为优化目标函数模型,采用非支配排序遗传算法进行参数优化。选择Cr12MoV模具钢材料进行单工步干式铣削沟槽正交实验,通过试验结果获得优化后最优的Pareto解集。考虑缩小优... 详细信息

为了实现模具制造过程的优质高效率生产,基于能量效率、表面质量为优化目标函数模型,采用非支配排序遗传算法进行参数优化。选择Cr12MoV模具钢材料进行单工步干式铣削沟槽正交实验,通过试验结果获得优化后最优的Pareto解集。考虑缩小优化结果的选择范围提升数控铣削方案的合理准确性,采用层次分析法对优化的参数组合方案进行评价分析。结果表明:应用层次分析法评价分析可以获得最佳目标参数组合方案,可实现数控机床加工模具钢过程中的高效率、高质量加工。

关键词：优质高效非支配排序遗传算法铣削参数优化层次分析法

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关节镜清理术治疗膝关节骨性关节炎

实用医技杂志 2004年第9B期11卷 1932-1933页

作者：焦宁姜海薛金山汪兵西安市红十字会医院陕西西安710054

目的 :探讨关节镜下行关节清理治疗膝关节骨性关节炎的疗效。方法 :对 33例 (44膝 )骨性关节炎患者 ,行膝关节镜检查 ,并在关节镜下行清理术。术后 3个月及 1a后复查 ,随访膝关节疼痛、肿胀及活动功能的改善情况。结果 :治疗后膝关节疼... 详细信息

目的 :探讨关节镜下行关节清理治疗膝关节骨性关节炎的疗效。方法 :对 33例 (44膝 )骨性关节炎患者 ,行膝关节镜检查 ,并在关节镜下行清理术。术后 3个月及 1a后复查 ,随访膝关节疼痛、肿胀及活动功能的改善情况。结果 :治疗后膝关节疼痛缓解、肿胀减轻、功能改善。术后 3个月复查 ,优良率达 85 % ;经 1a以上随访 ,优良率为72 % ,无复发及并发症。结论 :关节镜下行关节清理术治疗膝关节骨性关节炎是一种疗效好且简便的方法。

关键词：关节镜骨性关节炎清理术

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng Yang hai-Feng Song jin-shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

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Fiber Bending Flexibility Evaluation by Worm-like Chain Model

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Chinese Journal of Polymer Science 2022年第5期40卷 526-531页

作者： Chao jin Hui Yu Chun-Fang Wu hai-Bo Zhao shan-shan jin Yu-Liang Yang Hong-Dong Zhang Institute for Preservation and Conservation of Chinese Ancient Books Fudan UniversityShanghai 200433China Statekey laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

A new method for characterizing fiber bending flexibility was developed by worm-like chain model proposed by Kratky-Porod,[1]which was first introduced to the pulp and paper field in this *** the three types of pulps,the experimental results were compared with the KP chain model,and the resulting determination coefficients were all above 0.95,which proved that the model was feasible to be applied to these three *** relation between fiber bending rigidity and that of cellulosic chains inside was discussed to deduce the fiber bending *** flexibility of an individual fiber can be approximated as the contribution of that of all the cellulose chains *** this method,the fiber flexibility values were determined to be in the range of 0.6×10^(11)-3.5×10^(11)N^(-1)·m^(-2),which was comparable to that of the conventional methods recorded in the literature.

关键词： Worm-like chain Fiber persistence length Fiber bending flexibility

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铜绿假单胞菌色素代谢相关基因的研究

微生物学报 2005年第1期45卷 14-18,i003页

作者：徐海津单志英林伟利高才昌乔明强夏惠明徐姝娲张秀明白艳玲南开大学生命科学学院天津300071

首次应用Mu转座重组技术研究铜绿假单胞菌色素合成与调控的机制。通过一系列的表型筛选 ,得到 8株色素合成能力改变的突变子。经基因克隆、核苷酸测序研究 ,证明转座子分别插入到hmgA、ptsP、sucC、phzS、phzF1五个基因中。hmgA基因转... 详细信息

首次应用Mu转座重组技术研究铜绿假单胞菌色素合成与调控的机制。通过一系列的表型筛选 ,得到 8株色素合成能力改变的突变子。经基因克隆、核苷酸测序研究 ,证明转座子分别插入到hmgA、ptsP、sucC、phzS、phzF1五个基因中。hmgA基因转座失活导致酪氨酸分解代谢中间产物尿黑酸的积累 ,后四种情况转座突变显著地影响了铜绿假单胞菌最重要的色素绿脓素 (pyocyanin)的合成 ,其中PhzS和phzF1是绿脓素合成过程中的结构基因 ,ptsP基因是 1个磷酸转移酶系统的重要组分 ,sucC基因的产物是三羧酸循环中的琥珀酰辅酶A合成酶。

关键词：铜绿假单胞菌绿脓素 Mu转座重组技术

Field observation of wave overtopping at sea dike using shore-based video images

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Journal of Hydrodynamics 2021年第4期33卷 657-672页

作者： shan-hang Chi Chi Zhang Ti-ti Sui Zhu-bin Cao jin-hai Zheng Jiang-shan Fan State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing210098China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing210098China Rizhao Port Group Co. Ltd.Rizhao276826China

Wave overtopping at a sea dike was observed using video images during a storm in July 2018 at Rizhao Coast,China.A shore-based video monitoring system was mounted to collect coastal images with a sample frequency of 1 Hz in the beginning 10 min of each hour during daylight.A method to extract the frequency,location,width and duration of individual overtopping events based on the shore-based video monitoring system was developed.A total of 6252 individual overtopping events were detected over a 360m long sea dike during the storm of 10 h in a safe and labor-saving way,enabling a detailed analysis of the temporal and spatial variation of wave *** temporal variation of overtopping duration,frequency and volume is basically in sync with the change of tidal level(R=0.87,0.82 and 0.76,respectively).The increase of wave height increases the overtopping frequency *** found a high correlation between the hourly observed data and the predicted results of two commonly used *** the previous field measurements of overtopping that were limited in a single location,significant spatial variation of overtopping in the alongshore direction is *** overtopping volume varies with a factor of 6 within the range of several wave *** is further revealed that the spatial variation of overtopping is highly correlated with the alongshore variation of surf zone width with a correlation coefficient of *** present study suggests the feasibility of shore-based video monitoring technique to capture the main features of wave overtopping at coastal dikes,providing new possibilities to monitor wave overtopping in the field and to improve prediction tools.

关键词： Wave overtopping coastal video monitoring field measurement temporal and spatial variations storm events