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Chinese Journal of Structural Chemistry 2007年第2期26卷 149-152页

作者： li qing-xiang YANG xiang-liang XU Hui-Bi Hubei Key Laboratory of Novel Chemical Reactor andGreen Chemical Technology Wuhan Institute of Technology Wuhan 430073 China College of life Science Huazhong University of Science and Technology Wuhan 430074 China

A new dinuclear copper complex, [Cu（C13HgN2O）Cl]2.（CH3CN）2 （C30H24C12Cu2N6O2）, has been synthesized and characterized by X-ray structure determination. It crystallizes in the triclirile system, space group P1, with a = 7.6677（14）, b = 9.2375（17）, c = 11.227（2） ]A, α = 81.338（3）,β = 88.173（4）, γ = 66.199（3）°, V = 718.9（2） ]A^3, Z = 1, Mr = 698.53, F（000） = 354, Dc = 1.613 g/cm^3, μ（MoKa） = 1.705 mm^-1, the final R = 0.0645 and wR = 0.1364 for 2474 unique reflections with 1809 observed ones （I 〉 20（I））. In the title complex, each copper（H） atom is located at the center of a distorted tetrahedron consisting of four coordinate atoms （one nitrogen atom, two oxygen anions, and one chlorine atom）. Two copper（Ⅱ） atoms are bridged by two oxygen anions （O（1） and O（la）） of two phenolates to form a Cu（Ⅱ）-Cu（Ⅱ） binuclear entity, and the distance between two copper（Ⅱ） atoms is 3.0144（15） A.

关键词： 2-benzimidazol phenolate Cu(Ⅱ) complex crystal structure

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自适应序贯滤波的机器人融合定位方法研究

机械设计与制造 2024年第8期402卷 361-364页

作者：孙凌宇李庆翔李鑫宝王子航河北工业大学机械工程学院天津300401

针对激光雷达在长直环境下鲁棒性低以及视觉相机受光照条件影响大的问题,提出一种利用序贯卡尔曼滤波将两种传感器采集到的信息进行融合的定位方法,将传感器作为独立的节点逐级传递以实现多层次滤波,解决了异步传感器更新延迟导致算法... 详细信息

针对激光雷达在长直环境下鲁棒性低以及视觉相机受光照条件影响大的问题,提出一种利用序贯卡尔曼滤波将两种传感器采集到的信息进行融合的定位方法,将传感器作为独立的节点逐级传递以实现多层次滤波,解决了异步传感器更新延迟导致算法中断的问题,同时为算法添加自适应成分,避免了移动机器人长距离行驶过程中因缺少动态调节而产生发散的现象。仿真实验结果表明,以自适应序贯滤波的形式,融合定位结果显著降低了单一传感器测量带来的误差,有效提升了移动机器人在未知环境下的定位精度。

关键词：序贯滤波多传感融合机器人技术激光雷达视觉相机

Lanthanide Complexes with Acetylacetonate and 5,10,15,20-Tetra[para-|(4-chlorobenzoyloxy) phenyl]porphyrin

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Chemical Research in Chinese Universities 2000年第3期16卷 259-262页

作者： ZHAO Zhi-xin li xiang-qing WANG Xing-qiao liU Guo-fa Department of Chemistry Jilin UniversityChangchun 130023P.R.China

The lanthanide complexes of acetylacetonate and 5,10,15,20-tetra[para-(chlorobenzoyloxy)phenyl]porphyrin having a general formula Ln[(cbop)4p]acac (where Ln = Tb, Ho, Er, Tm; cbop = (4-chlorobenzoyloxy)phenyl; Hacac =... 详细信息

关键词： Lanthanide complexes Porphyrin Acetylacetone

Overview of global monthly surface temperature data in the past century and preliminary integration

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Advances in Climate Change Research 2014年第3期5卷 111-117页

作者： XU Wen-Hui li qing-xiang YANG Su XU Yan National Meteorological Information Center China Meteorological Administration

This paper analyzes the status of existing resources through extensive research and international cooperation on the basis of four typical global monthly surface temperature datasets including the climate research dataset of the University of East Anglia(CRUTEM3), the dataset of the U.S. National Climatic Data Center(GHCN-V3), the dataset of the U.S. National Aeronautics and Space Administration(GISSTMP), and the Berkeley Earth surface temperature dataset(Berkeley). China's first global monthly temperature dataset over land was developed by integrating the four aforementioned global temperature datasets and several regional datasets from major countries or regions. This dataset contains information from 9,519 stations worldwide of at least 20 years for monthly mean temperature, 7,073 for maximum temperature, and 6,587 for minimum temperature. Compared with CRUTEM3 and GHCN-V3, the station density is much higher particularly for South America, Africa,and Asia. Moreover, data from significantly more stations were available after the year 1990 which dramatically reduced the uncertainty of the estimated global temperature trend during 1990e2011. The integrated dataset can serve as a reliable data source for global climate change research.

关键词： Global monthly surface temperature dataset Integration of multi-source data Climate change

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： qing-Ping li Jin-Ya Zhang Jia-xiang Zhang Yong-Xue Zhang CNOOC Research Institute Company limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump liquid film seal Pressure disturbance wave Dynamic response characteristics

Seasonal response of nitrogen exchange fluxes to crab disturbance at sediment-water interface in coastal tidal wetlands

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Water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing liu xiang-dong liu Jin-li li Yue Fang Wen-ting Xie xiang Xu College of Water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh ***,the underlying mechanisms remain *** study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat *** results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and *** to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without *** summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early *** winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative *** results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

应用擦拭法消毒口腔综合治疗台高速涡轮手机快接头连接口对出水含菌量的影响研究

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中国实用口腔科杂志 2024年第3期17卷 313-317页

作者：赵丹丹李庆祥于雅婷杜丽娜崔念晖北京大学口腔医学院·口腔医院口腔颌面外科国家口腔医学中心国家口腔疾病临床医学研究中心口腔生物材料和数字诊疗装备国家工程研究中心口腔数字医学北京市重点实验室国家卫生健康委口腔数字医学重点实验室国家药品监督管理局口腔生物材料重点实验室北京100081

目的研究应用擦拭法消毒口腔综合治疗台高速涡轮手机快接头连接口对出水含菌量的影响。方法研究于2022年7—11月在北京大学口腔医学院·口腔医院中心实验室进行。选取北京大学口腔医学院·口腔医院口腔颌面外科门诊诊室中具有高速涡... 详细信息

目的研究应用擦拭法消毒口腔综合治疗台高速涡轮手机快接头连接口对出水含菌量的影响。方法研究于2022年7—11月在北京大学口腔医学院·口腔医院中心实验室进行。选取北京大学口腔医学院·口腔医院口腔颌面外科门诊诊室中具有高速涡轮手机快接头的口腔综合治疗台24台。随机选取其中8台,于开诊前30 min采集高速涡轮手机快接头连接口处及出水样本,擦拭法消毒连接口后再次采样;重复检测3次,每次间隔14 d。将另16台口腔综合治疗台随机分为研究组和对照组(每组8台),对照组采用水冲法进行常规诊前管路准备,研究组在水冲法前增加擦拭法,管路准备完成后采集2组出水样本;重复检测3次,每次间隔14 d。比较消毒前后及2组之间连接口处及出水样本含菌量,并采用Pearson相关性分析检验出水样本与连接口处样本含菌量的相关性。结果 3次取样检测结果显示,擦拭法消毒后连接口处含菌量分别为(795.8±1141.6)、(1163.8±1124.0)、(1173.4±960.1)CFU/mL,出水样本含菌量分别为(103.5±63.6)、(94.1±71.7)、(108.1±57.1)CFU/mL,较消毒前连接口处样本[(5459.4±4561.6)、(9079.4±6602.5)、(6605.0±3488.3)CFU/mL]及出水样本[(300.1±44.5)、(324.0±167.4)、(346.1±49.1)CFU/mL]明显下降,差异均有统计学意义(均P <0.05);且出水样本与连接口处样本含菌量之间呈正相关(r=0.789,P=0.020)。研究组3次取样连接口处含菌量分别为(94.5±93.0)、(91.3±87.3)、(116.3±73.5)CFU/mL,出水样本含菌量分别为(79.5±25.9)、(78.1±25.4)、(65.9±24.6)CFU/mL,较对照组连接处样本[(6318.0±1750.6)、(6366.9±1672.5)、(6321.6±1650.9)CFU/mL]及出水样本[(308.9±124.5)、(352.1±112.6)、(298.1±98.7)CFU/mL]明显下降,差异均有统计学意义(均P <0.05)。结论高速涡轮手机快接头连接口处存在一定数量的细菌,且含菌量与出水含菌量呈正相关。对连接口表面进行擦拭消毒,可有效降低出水含菌量。

关键词：高速涡轮手机快接头口腔综合治疗台水路微生物消毒

Microstructure design of advanced magnesium-air battery anodes

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Journal of Magnesium and Alloys 2024年第2期12卷 443-464页

作者： Xu Huang qingwei Dai qing xiang Na Yang Gaopeng Zhang Ao Shen Wanming li School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China School of Materials and Architectural Engineering Guizhou Normal UniversityGuiyang 550025China School of Material and Metallurgy University of Science and Technology LiaoningAnshan 114051China

Metal-air battery is an environmental friendly energy storage system with unique open ***(Mg)and its alloys have been extensively attempted as anodes for air batteries due to high theoretical energy density,low cost,and ***,the study on Mg-air battery(MAB)is still at the laboratory level currently,mainly owing to the low anodic efficiency caused by the poor corrosion *** order to reduce corrosion losses and achieve optimal utilization efficiency of Mg anode,the design strategies are reviewed from microstructure ***,the corrosion behaviors have been discussed,especially the negative difference effect derived by hydrogen *** attention is given to the effect of anode micro-structures on the MAB,which includes grain size,grain orientation,second phases,crystal structure,twins,and *** further improvement,the discharge performance,long period stacking ordered phase and its enhancing effect are ***,given the current debates over Mg dendrites,the potential risk,the impact on discharge,and the elimination strategies are *** control and single crystal would be promising ways for MAB anode.

关键词： Magnesium Air battery Anode Microstructure Anodic efficiency

Synthesis of Planar-Chiral[2.2]Paracyclophane-Based Oxazole-Pyrimidine ligands and Application in Nickel-Catalyzed 1,2-Reduction ofα,β-Unsaturated Ketones

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Chinese Journal of Chemistry 2024年第7期42卷 705-710页

作者： Juan Wang qing-Xian Xie xiang li Chang-Bin Yu Yong-Gui Zhou School of Chemistry Dalian University of Technology2 Linggong RoadDalianLiaoning 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China

The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric *** them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural ***,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%***,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.

关键词： Oxazole-pyrimidine ligands Planar chirality Nickel Hydroboration Asymmetric synthesis

Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： Peng SI qing-xiang li Xiao-Yang CHEN Min WANG Chuan-Jun LUO Tianjin Meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China Shaoguan Meteorological Service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin Meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period