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Synthesis and Crystal Structure of (CO) 5ReSnMe 2Re(CO) 5

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Chinese Journal of Structural Chemistry 1999年第2期18卷 39-43页

作者： li, J liu, H Song, XQ kai, l Yin, N Nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China Nankai Univ Inst Elementoorgan Chem Tianjin 300071 Peoples R China

The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space group P2 1/n (NO.14), a=10.587(2), b=12.392(2), c = 14.594(3) , β = 100.59(3)°, V = 1882(1) 3, D x = 2.828 g·cm -3 , F(000)=1432, μ =14.3759mm -1 , Z =4, and final R =0 0440 and R w =0 0483 for 1954 reflections ( I≥3σ(I )). In the complex the Sn atom is connected to two methyl groups and two Re atoms which are in slightly distorted tetrahedral arrangement. The Re atom is coordinated by five carbonyl ligands and one Sn atom, forming an octahedral structure.

关键词： metal carbonyl cluster Re complex synthesis crystal structure

Carbonation Resistance of Hybrid NanoSiO_(2) Modified Cementitious Surface Protection Materials

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Journal of Wuhan University of Technology(Materials Science) 2022年第5期37卷 855-862页

作者： XIA kailun GU Yue JIN Weizhun JIANG linhua lükai GUO Mingzhi College of Mechanics and Materials Hohai UniversityNanjing211100China College of Civil and Transportation Engineering Hohai UniversityNanjing210000China

Hybrid nanoSiO_(2) (HNS) modified cement pastes were explored as a kind of surface protection material (SPM).The carbonation resistance and mechanical properties of SPMs coated samples were *** analysis (TGA),X-ray diffraction (XRD),scanning electron microscope (SEM),and mercury intrusion porosimetry (MIP) were further employed to evaluate the chemical composition and microstructure characteristics of ***,thermodynamic modeling was adopted to simulate the changes in the phase assemblages of SPM under the carbonation *** results showed that SPM with 1 wt% HNS could effectively enhance the carbonation *** incorporation of HNS could densify the microstructure and refine the pore ***,the thaumasite can be stable at ambient temperature with the addition of HNS,which is beneficial to maintain alkalinity under the carbonation process.

关键词： hybrid nanoSiO_(2) carbonation resistance surface protection materials pore structure

The comparison of ensemble or deterministic dispersion modeling on global dispersion during Fukushima Dai-ichi nuclear accident

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Science China Earth Sciences 2015年第3期58卷 356-370页

作者： SHENG li SONG ZhenXin HU Jiangkai lü kai TONG Hua lI Bing QIAO QingDang National Meteorological Center China Meteorological Administration Nuclear and Radiation Safety Center Ministry of Environmental Protection of the People's Republic of China

Ensemble forcasting,originally developed for weather prediction,is lately being extended to atmospheric dispersion applications,which is a new,effective methodology for improving the atmospheric dispersion numerical *** March 2011,due to the massive 9.0 earthquakes and ensuing tsunami that struck off the northern coast of the island of Honshu,the Fukushima Nuclear Plant I had the substantial leak of radioactive materials into surrounding environment and *** aim at the global dispersion modeling of atmospheric radionuclides from Fukushima Nuclear Accident,this paper presents two approaches of atmospheric dispersion forecasting:ensemble dispersion modeling(EDM) and deterministic dispersion modeling(DDM),conducts the globally dispersion modeling cases for Fukushima nuclear accident,and analyzes and evaluates the simulation results using observation *** this paper,EDM includes three different perturbation methods:meteorological perturbation method,turbulence perturbation method,and physical parameterization ensemble forecasting *** simulation results show that the trajectories from EDM have a better performance,which is in better agreement with the atmospheric circulation and observation data; the spread from DDM is slower and not as far as ***,the results from EDM display a better performance in the modeling of transport from Japan to China East Sea on April *** reasons for these results are:the techniques of MET and TUR are performed by adding perturbations on mean wind and turbulent velocity,respectively; the various different flow fields will result in far spreading in horizontal and the simulation results closer to observation; PHY is performed by using different diffusion physical parameterizations and produces the perturbations on vertical wind,which results the spreading in smaller range and discontinuous in ***,the comparative analysis between modeling results and observation data shows that all cases r

关键词： ensemble dispersion modeling deterministic dispersion modeling atmospheric dispersion Fukushima nuclear accident

Investigation of temperature-dependent small-signal performances of TB SOI MOSFETs

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Journal of Semiconductors 2017年第4期38卷 58-62页

作者： Yuping Huang Jun liu kai lü Jing Chen Key laboratory tbr RF Circuits and Systems(Hangzhou Dianzi University) Ministry of EducationHangzhou 310018China

This paper investigated the temperature dependence of the cryogenic small-signal ac performances of multi-finger partially depleted（PD） silicon-on-insulator（SOI） metal oxide semiconductor field effect transistors（MOSFETs）,with T-gate body contact（TB） *** measurement results show that the cut-off frequency increases from 78 GHz at 300 K to 120 GHz at 77 K and the maximum oscillation frequency increases from 54 GHz at 300 K to 80 GHz at 77 K,and these are mainly due to the effect of negative temperature dependence of threshold voltage and *** using a simple equivalent circuit model,the temperature-dependent small-signal parameters are discussed in *** understanding of cryogenic small-signal performance is beneficial to develop the PD SOI MOSFETs integrated circuits for ultra-low temperature applications.

关键词： cryogenic small-signal AC performance PD SOI MOSFETs

Bending strength and fracture surface topography of natural fiber-reinforced shell for investment casting process

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China Foundry 2016年第3期13卷 211-216页

作者： kai lü Xiang-dong liu Zhao-xin Du Yan-fen li School of Materials Science and Engineering inner Mongolia University of Technology Hohhot 010051 China Key laboratory of Materials Processing & Control Engineering of Inner Mongolia Autonomous Region Hohhot 010051 China

In order to improve the properties of silica sol shell for investment casting process, various contents of cattail fibers were added into the slurry to prepare a fiber-reinforced shell in the present study. The bending strength of fiber-reinforced shell was investigated and the fracture surfaces of shell specimens were observed using SEM. It is found that the bending strength increases with the increase of fiber content, and the bending strength of a green shell with 1.0 wt.% fiber addition increases by 44% compared to the fiber-free shell. The failure of specimens of the fiber-reinforced green shell results from fiber rupture and debonding between the interface of fibers and adhesive under the bending load. The micro-crack propagation in the matrix is inhibited by the micro-holes for ablation of f ibers in specimens of the f iber-reinforced shell during the stage of being fired. As a result, the bending strength of specimens of the fired shell had no significant drop. Particularly, the bending strength of specimens of the fired shell reinforced with 0.6wt.% fiber reached the maximum value of 4.6 MPa.

关键词： fiber-reinforced shell investment casting bending strength fracture surface topography

基于B样条和水平集方法的医学图像联合分割与配准

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激光与光电子学进展 2020年第10期57卷 78-88页

作者：吕凯吴军江西理工大学信息工程学院江西赣州341000

针对分层B样条非刚性配准存在局部极值以及水平集分割方法不适用于噪声图像分割的问题,提出了一种基于局部更新分层B样条双向变换和水平集方法的医学图像联合分割与配准方法。该方法在分割算法中加入配准变换,在配准中融入图像分割的结... 详细信息

针对分层B样条非刚性配准存在局部极值以及水平集分割方法不适用于噪声图像分割的问题,提出了一种基于局部更新分层B样条双向变换和水平集方法的医学图像联合分割与配准方法。该方法在分割算法中加入配准变换,在配准中融入图像分割的结构信息。使用B样条水平集函数对变换和分割的图像进行平滑表示,并在配准中引入双向变换以提高配准的精度和平滑性。在水平集方法的基础上,引入双向分层B样条变换构造分割与配准的联合能量泛函,并结合梯度下降法将能量泛函最小化以优化目标函数。实验结果表明:本方法与单独的图像分割方法相比,Dice度量均在99%以上;与单独的图像配准方法相比,均方误差下降了30%,能够提高图像的配准精度,且在分割噪声图像时有较好的鲁棒性。

关键词：分层B样条水平集图像配准图像分割

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可持续发展的环境法立法目的及其发展

天津大学学报（社会科学版） 2013年第1期15卷 87-92页

作者：吕凯天津大学文法学院天津300072

随着世界各国经济发展与环境之间矛盾的日趋尖锐,原有的"一元论"、"二元论"环境法的目的的规定已经不能适应人们对环境问题认识的加深。既满足当代人的需要,又不对后代人满足其需要的可持续发展理论应运而生,并在立法实践中得到许多国... 详细信息

随着世界各国经济发展与环境之间矛盾的日趋尖锐,原有的"一元论"、"二元论"环境法的目的的规定已经不能适应人们对环境问题认识的加深。既满足当代人的需要,又不对后代人满足其需要的可持续发展理论应运而生,并在立法实践中得到许多国家的认可并采纳。但结合当前经济发展的实际,综合审视可持续发展理论却可以发现它仍然存在一些问题。因此,环境与人类共同科学发展作为环境法的立法目的在将来更符合自然规律和人类发展的要求。

关键词：可持续发展环境科学发展

Degradation of Disposal Hydroxyl-Terminated Polybutadiene Composite Solid Propellant

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Wuhan University Journal of Natural Sciences 2020年第3期25卷 201-207页

作者： lU kai YI Ying ZHENG Hua SHU kaikai DENG Anhua HU Taoxian NIU Caoping lI Dan School of Chemistry Chemical Engineering and Life ScienceWuhan University ofTechnologyWuhan 430070HubeiChina Hubei Sanjiang Aerospace Jianghe Chemical Tech no logy Co. LtdYichang 444200HubeiChina

With the greatly increasing amount of discarded hydroxyl-terminated polybutadiene(HTPB)propellant year by year,it is of high significance to study the safe,efficient and environmental processing method of disposal HTPB *** this paper,the decomposition agents are formulated for degrading the waste composite solid *** is found that the following formulations of butanone 25%-55%,xylene 30%-75%,deionized water 40%-45%have effective influence on the degradation of the waste composite solid *** proper degradation time is found to be about 7-8 *** the help of infrared spectrum analysis,scanning electron microscope imaging,thermogravimetric analysis and solvent viscosity test,it was proved that after degradation reaction on the propellant sometimes,a large number of irregular fractures occurred in bulk resulting from effective *** characterization of the propellant after degradation showed that the hardness of the propellant decreased,the viscosity increased,and a large number of holes and cracks appeared on the *** results showed that the formulated degradation agent and degradation condition perform good degradation effects on HTPB solid propellant.

关键词： hydroxyl-terminated polybutadiene(HTPB)composite solid propellant mixed degradation agent degradation

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半空间上MHD方程弱解的衰减下界

东华大学学报（自然科学版） 2016年第1期42卷 160-166页

作者：吕锴东华大学理学院上海201620

研究了磁流体力学(MHD)方程的弱解在半空间Rn+上的衰减性质,通过建立一族产生弱衰减的初值,得到了MHD方程的衰减下界.

关键词：磁流体力学(MHD)方程半空间衰减下界