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Survival Probability of Population-size-dependent Branching Processes in Random Environments

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Acta mathematicae Applicatae Sinica 2016年第2期32卷 477-484页

作者： Shi-xia ma xiao-yu XING School of Sciences Hebei University of Technology

The class of population-size-dependent branching processes in independent identically distributed random environments is investigated. Under the critical case and appropriate moment assumption, we establish an asympto... 详细信息

关键词： branching processes population-size-dependent processes random environments survival proba-bility

Transition toward thorium fuel cycle in a molten salt reactor by using plutonium

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Nuclear Science and Techniques 2017年第10期28卷 103-112页

作者： De-Yang Cui Shao-Peng Xia xiao-xiao Li xiang-Zhou Cai Jin-Gen Chen Shanghai Institute of Applied Physics Chinese Academy ofSciencesShanghai 201800China CAS Innovative Academies in TMSR Energy System Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The molten salt reactor(MSR), as one of the Generation Ⅳ advanced nuclear systems, has attracted a worldwide interest due to its excellent performances in safety, economics, sustainability, and proliferation resistance. The aim of this work is to provide and evaluate possible solutions to fissile 233 U production and further the fuel transition to thorium fuel cycle in a thermal MSR by using plutonium partitioned from light water reactors spent fuel. By using an in-house developed tool, a breeding and burning(B&B) scenario is first introduced and analyzed from the aspects of the evolution of main nuclides, net 233 U production, spectrum shift, and temperature feedback coefficient. It can be concluded that such a Th/Pu to Th/^(233)U transition can be accomplished by employing a relatively fast fuel reprocessing with a cycle time less than 60 days. At the equilibrium state, the reactor can achieve a conversion ratio of about 0.996 for the 60-day reprocessing period(RP) case and about 1.047 for the 10-day RP *** results also show that it is difficult to accomplish such a fuel transition with limited reprocessing(RP is 180 days),and the reactor operates as a converter and burns the plutonium with the help of thorium. Meanwhile, a prebreeding and burning(PB&B) scenario is also analyzed briefly with respect to the net 233 U production and evolution of main nuclides. One can find that it is more efficient to produce 233 U under this scenario, resulting in a double time varying from about 1.96 years for the 10-day RP case to about 6.15 years for the 180-day RP case.

关键词：钍燃料循环反应器熔盐堆先进核能系统钚循环时间轻水反应堆燃料后处理

Kinematic Calibration of Asymmetricly Actuated 6-DOF 3-PPPS Parallel Mechanism

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第3期33卷 294-300页

作者： Chen Lei Huang xiang ma Zhiqiang Li Shuanggao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Institute of Aeronautical manufacturing Technology Research Shanghai Aircraft Manufacturing Co.Ltd

An asymmetric actuated 3-PPPS parallel mechanism was analyzed in its application to an aircraft wing adjustment *** posture alignment precision at the wing ends was enhanced with a kinematic calibration method.A constraint equation was built based on a constraint condition that distances among spherical joints of the mechanism were constant,and further eight groups of analytic forward solutions of all poses of the mechanism were *** inverse equation of the posture alignment displacements of aircraft wing parts was built based on space vector chains,and a mapping equation of the pose and geometric errors of the posture alignment mechanism containing 39 error sources was derived by differentiating the kinematic equation of the *** kinematic calibration experiments,the maximum position error of the posture alignment platform dropped from 2.67 mm to 0.82 mm,the maximum angle error decreased from 0.481° to 0.167°,and the posture alignment precision of the aircraft wing end was improved.

关键词： aircraft wing adjustment parallel mechanism forward numerical solution laser tracker kinematic calibration

A Lindqvist-type [W_(6)O_(19)]^(2-) organic–inorganic compound: synthesis, characterization, antibacterial activity and preliminary studies on the mechanism of action

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Tungsten 2022年第2期4卷 121-129页

作者： Meng Zhao Xi-Yu Zhu Yan-Zhen Li Jiang-Nan Chang Ming-Xue Li Li-Hua ma xiao-Yuan Guo Henan Key Laboratory of Polyoxometalate Chemistry Institute of Molecular and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng475004China Agricultural Products’Quality and Safety Testing Center of Kaifeng Kaifeng Agriculture and Rural BureauHenan475004China

In this paper,a new organic–inorganic hybrid compound[Co(L)_(2)]2[W_(6)O_(19)](1)(HL=2-acetylpyridine thiosemicarbazone)was prepared and *** compound 1 exhibits remarkable antibacterial activity by determination of minimum inhibitory concentration(MIC)against Staphylococcus aureus(***,0.06μg·mL^(−1))and Escherichia coli(***,0.24μg·mL^(−1)),***,the potential mechanism of compound 1 was studied in *** potential causes of bacteria death were cell wall/membrane disruption,inhibition of intracellular respiratory chain dehydrogenases(RCD)activity,destruction of reactive oxygen species(ROS)and depletion of glutathione(GSH).

关键词： Isopolytungstate Thiosemicarbazone Bioactivity Mechanism of action

The vertical structure of the atmospheric boundary layer over the central Arctic Ocean

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Acta Oceanologica Sinica 2013年第10期32卷 34-40页

作者： BIAN Lingen ma Yongfeng LU Changgui LIN xiang Chinese Academy of Meteorological Sciences

The tropopause height and the atmospheric boundarylayer （PBL） height as well as the variation of inversion layer above the floating ice surface are presented using GPS （global position system ） radiosonde sounding data and relevant data obtained by Chinas fourth arctic scientific expedition team over the central Arctic Ocean （86°-88°N, 144°-170°W） during the summer of 2010. The tropopause height is from 9.8 to 10.5 km, with a temperature range between -52.2 and -54.10C in the central Arctic Ocean. Two zones of maximum wind （over 12 m/s） are found in the wind profile, namely, low- and upper-level jets, located in the middle troposphere and the tropopause, respectively. The wind direction has a marked variation point in the two jets from the southeast to the southwest. The average PBL height determined by two methods is 341 and 453 m respectively. These two methods can both be used when the inversion layer is very low, but the results vary significantly when the inversion layer is very high. A significant logarithmic relationship exists between the PBL height and the inversion intensity, with a correlation coefficient of 0.66, indicating that the more intense the temperature inversion is, the lower the boundary layer will be. The observation results obviously differ from those of the third arctic expedition zone （800-85° N）. The PBL height and the inversion layer thickness are much lower than those at 870-88° N, but the inversion temperature is more intense, meaning a strong ice- atmosphere interaction in the sea near the North Pole. The PBL structure is related to the weather system and the sea ice concentration, which affects the observation station.

关键词： central Arctic Ocean radiosonde sounding PBL height inversion layer

Prediction of biventricular repair by echocardiography in borderline ventricle

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Chinese Medical Journal 2019年第17期132卷 2105-2108页

作者： xiao-Jing ma Guo-Ying Huang Heart Center Children’s Hospital of Fudan University Shanghai 201102 China National Children’s Medical Center Shanghai 201102 China Shanghai Key Laboratory of Birth Defects Shanghai 201102 China

Objective: In recent years, attempting the biventricular pathway or biventricular conversions in patients with borderline ventricle has become a hot topic. However, inappropriate pursuit of biventricular repair in borderline candidates will lead to adverse clinical outcomes. Therefore, it is important to accurately assess the degree of ventricular development before operation and whether it can tolerate biventricular repair. This review evaluated ventricular development using echocardiography for a better prediction of biventricular repair in borderline ventricle. Data sources: Articles from January 1, 1990 to April 1, 2019 on biventricular repair in borderline ventricle were accessed from PubMed, using keywords including "borderline ventricle,""congenital heart disease,""CHD,""echocardiography," and "biventricular repair." Study selection: Original articles and critical reviews relevant to the review’s theme were selected. Results: Borderline left ventricle (LV):(1) Critical aortic stenosis: the Rhodes score, Congenital Heart Surgeons Society regression equation and another new scoring system was proposed to predict the feasibility of biventricular repair.(2) Aortic arch hypoplasia: the LV size and the diameter of aortic and mitral valve (MV) annulus should be taken into considerations for biventricular repair.(3) Right-dominant unbalanced atrioventricular septal defect (AVSD): atrioventricular valve index (AVVI), left ventricular inflow index (LVII), and right ventricle (RV)/LV inflow angle were the echocardiographic indices for biventricular repair. Borderline RV:(1) pulmonary atresia/intact ventricular septum (PA/IVS): the diameter z-score of tricuspid valve (TV) annulus, ratio of TV to MV diameter, RV inlet length z-score, RV area z-score, RV development index, and RV-TV index, etc. Less objective but more practical description is to classify the RV as tripartite, bipartite, and unipartite. The presence or absence of RV sinusoids, RV dependent coronary circulat

关键词： Borderline ventricle Congenital heart disease Echocardiography Biventricular repair

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茶树新品系‘福茗2号’区域试验报告

茶叶学报 2024年第2期65卷 38-44页

作者：游小妹李鑫磊陈志辉孔祥瑞单睿阳陈常颂福建省农业科学院茶叶研究所/国家茶树改良中心福建分中心福建福州350013

【目的】选育早生、高产、高香茶树新品种,满足消费需求的多样化。【方法】以‘黄棪’为对照,在福建福安、松溪、福州3个区试点对‘福茗2号’新品系的种植成活率、物候期(一芽一叶、一芽二叶和一芽三叶期)、鲜叶产量、制茶品质、抗性等... 详细信息

【目的】选育早生、高产、高香茶树新品种,满足消费需求的多样化。【方法】以‘黄棪’为对照,在福建福安、松溪、福州3个区试点对‘福茗2号’新品系的种植成活率、物候期(一芽一叶、一芽二叶和一芽三叶期)、鲜叶产量、制茶品质、抗性等方面进行为期6年(2016—2021年)的茶树品种区域试验。【结果】‘福茗2号’新品系种植成活率高,达89%以上;物候期比对照早1~2 d;鲜叶产量比对照高5%左右;制乌龙茶品质比对照高出0.5~1.1分;耐寒、耐旱性强,茶炭疽病和茶小绿叶蝉抗性均表现为抗。【结论】‘福茗2号’是一个早生、高产、优质、高抗的乌龙茶新品种,适宜在福建福安、松溪、福州及相似乌龙茶地区种植和推广应用。

关键词：茶树福茗2号新品系乌龙茶适应性

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响应面法优化三元低共熔溶剂提取克氏原螯虾中的甲壳素

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化学试剂 2024年第4期46卷 50-58页

作者：何晓希杨荣玲朱千林赵祥杰吴彬邵灿灿淮阴工学院生命科学与食品工程学院江苏淮安223003 淮安市产品质量监督综合检验中心江苏淮安223001

以制备的三元低共熔溶剂提取克氏原螯虾中的甲壳素,分别考察甲壳素提取过程中低共熔溶剂物质的量比、反应时间和固液比对甲壳素提取率的影响,通过单因素优化确定不同因素对甲壳素提取影响的最佳参数,在单因素实验结果基础上开展响应面... 详细信息

以制备的三元低共熔溶剂提取克氏原螯虾中的甲壳素,分别考察甲壳素提取过程中低共熔溶剂物质的量比、反应时间和固液比对甲壳素提取率的影响,通过单因素优化确定不同因素对甲壳素提取影响的最佳参数,在单因素实验结果基础上开展响应面实验设计,确定甲壳素最优提取工艺参数,通过傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)和扫描电镜(SEM)对甲壳素进行表征,明确其性质。结果表明,以氯化胆碱、乳酸和乙酸组成的三元低共熔溶剂作为优选提取溶剂进行提取优化时,当固液比为1∶10.8、反应时间为2.50 h、低共熔溶剂物质的量比为1∶2.8∶1,甲壳素提取率最高可达31.72%,比常规酸碱法提取率更高。通过傅里叶变换红外光谱和X射线衍射可以看出所提取甲壳素的特征峰情况和钙的脱除状况,扫描电镜照片可以清楚地看出其表面形貌特征。

关键词：三元低共熔溶剂克氏原螯虾甲壳素响应面法提取

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Synthetical Efficiency-based Optimization for the Power Distribution of Power-split Hybrid Electric Vehicles

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 58-68页

作者： WANG Weida HAN Lijin xiang Changle ma Yue LIU Hui National Key Laboratory of Vehicle Transmission Beijing Institute of Technology

Now the optimization strategies for power distribution are researched widely, and most of them are aiming to the optimal fuel economy and the driving cycle must be preknown. Thus if the actual driving condition deviates from the scheduled driving cycle, the effect of optimal results will be declined greatly. Therefore, the instantaneous optimization strategy carried out on-line is studied in this paper. The power split path and the transmission efficiency are analyzed based on a special power-split scheme and the efficiency models of the power transmitting components are established. The synthetical efficiency optimization model is established for enhancing the transmission efficiency and the fuel economy. The identification of the synthetical efficiency as the optimization objective and the constrain group are discussed emphatically. The optimization is calculated by the adaptive simulated annealing （ASA） algorithm and realized on-line by the radial basis function （RBF）-based similar models. The optimization for power distribution of the hybrid vehicle in an actual driving condition is carried out and the road test results are presented. The test results indicate that the synthetical efficiency optimization method can enhance the transmission efficiency and the fuel economy of the power-split hybrid electric vehicle （HEV） observably. Compared to the rules-based strategy the optimization strategy is optimal and achieves the approximate global optimization solution for the power distribution. The synthetical efficiency optimization solved by ASA algorithm can give attentions to both optimization quality and calculation efficiency, thus it has good application foreground for the power distribution of power-split HEV.

关键词： hybrid electric vehicles power-split synthetical efficiency-based optimization power distribution road test