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Journal of Thermal Science 2018年第1期27卷 17-24页

作者： WANG yi HAN ge LU Xingen ZHU Junqiang School of Aeronautics and Astronautics Central South UniversityChangsha 410083China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China

Wedge diffuser is widely used in centrifugal compressors due to its high performance and compact size. This paper is aimed to research the influence of wedge diffuser blade number and divergence angle on centrifugal compressor performance. The impact of wedge diffuser blade number on compressor stage performance is investigated, and then the wedge diffusers with different divergence angle are studied by varying diffuser wedge angle and blade number simultaneously. It is found that wedge diffuser with 27 blades could have about 0.8% higher adiabatic efficiency and 0.14 higher total pressure ratio than the wedge diffuser with 19 blades and the best compressor performance is achieved when diffuser divergence angle is 8.3°.These results could give some advices on centrifugal compressor design.

关键词： Wedge diffuser Blade number Diffuser angle High pressure ratio Centrifugal compressor

A method for neutron-induced gamma spectra decomposition analysis based on geant4 simulation

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Nuclear Science and Techniques 2022年第12期33卷 36-48页

作者： Wei Tang Jin-Gang Liang yi ge Qiong Zhang University of Electronic Science and Technology of China Chengdu 610000China Tsinghua University Beijing 10000China

In various monitoring and detection tools that use pulsed neutron generators as radiation sources,the gamma rays induced by the interaction with various nuclei at different stages of neutron transport can reflect information about the *** gamma rays are generated in two major interactions:inelastic scattering of fast neutrons and radiative capture of thermal neutrons,corresponding to the inelastic and capture gamma rays,***,the two types of gamma rays that reflect different properties of the medium are difficult to collect by normal detectors *** proportion of the two gamma rays needs to be solved for the separation of inelastic and capture ***,this study proposes an optimized spectra decomposition method to calculate the inelastic-to-capture ratio in the measured total gamma spectra based on the net inelastic and capture spectra obtained using the geant4 *** the simulated data cannot reflect the energy resolution of the measured spectra,we introduce the Gaussian broadening function of the gamma detector while calculating the proportion of the spectra components,and achieve optimization of the proportion values and resolution parameters *** on the results,the total simulated spectra obtained by superimposing the broadened net inelastic and capture gamma spectra according to the calculated inelastic-to-capture ratio are in good agreement with their measured counterpart.

关键词： Neutron-induced gamma geant4 Spectra analysis

ge-semigroup method for controllability of stochastic descriptor linear systems

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Science China(Information Sciences) 2023年第3期66卷 299-300页

作者： Zhaoqiang ge School of Mathematics and Statistics Xi’an Jiaotong University

Dear editor, Nowadays, there are more and more researches on stochastic descriptor systems(see [1–7]). For example, Refs. [4,5] studied the exact controllability of a class of stochastic descriptor systems by a strongly continuous semigroup in Hilbert spaces. In this study, the exact controllability and approximate controllability of the following stochastic descriptor system are studied by using the ge-semigroup theory, respectively:

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A direct polymeric carbon nitride/tungsten oxide Z-scheme heterostructure for efficient photocatalytic hydrogen generation via reforming of plastics into value-added chemicals

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Rare Metals 2024年第8期43卷 3771-3783页

作者： rui-Zhe Wang Zhi Lin yi-Qing Wang Kai-Ni Zhang ge-Hong Zhang Jie Zhang Samuel S.Mao Shao-Hua Shen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049China School of Civil and Architecture Engineering Xi'an Technological UniversityXi'an 710021China Department of Mechanical Engineering University of California at BerkeleyBerkeleyCA94720USA

To promote charge transfer and separation for efficient photocatalysis,a direct Z-scheme heterostructure was constructed by coupling polymeric carbon nitride(PCN) and WO_(3).Interestingly,the obtained PCN/WO_(3)Z-scheme heterostructure could photocataly tic ally produce hydrogen and value-added chemicals(e.g.,formate and acetate) by reforming of plastic polylactic acid(PLA) in alkaline aqueous *** optimizing WO_(3) contents and reaction conditions,the obtained PCN/WO_(3)heterostructure exhibits much increased photocatalytic activity for PLA photoreforming under visible light,with hydrogen evolution rate reaching 402.90 μmol·g~(-1)·h~(-1),which is 3.5 times that of *** is revealed that the Z-scheme charge transfer between PCN and WO_(3) mainly contributes to the promoted charge separation and thus the improved photocatalytic ***,with h+and·OH experimentally evidenced as the predominant active species,a possible reaction pathway for the reforming of PLA into value-added chemicals(e.g.,formate and acetate)over PCN/WO_(3) Z-scheme heterostructure is cleared by monitoring the reaction intermediates and *** work paves a carbon neutrality and scalable route toward the synergistical production of hydrogen and value-added chemicals by utilizing and recycling plastic waste.

关键词： Carbon nitride Z-scheme heterojunction Plastic waste conversion Photocatalytic H_(2)production Value-added chemicals

ADSORPTION OF TiCl_4 AND ELECTRON DONOR ON DEFECTIVE MgCl_2 SURFACES AND PROPYLENE POLYMERIZATION OVER ZIEGLER-NATTA CATALYST: A DFT STUDY

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Chinese Journal of Polymer Science 2013年第4期31卷 591-600页

作者： rui-hua Cheng Jun Luo Zhen Liu Jing-wen Sun Wei-huan Huang Ming-ge Zhang Jian-jun yi 刘柏平 State Key Laboratory of Chemical Engineering East China University of Science and Technology Petrochemical Research Institute China National Petroleum Corporation

The formations of defective MgC12 surfaces, and subsequent adsorption of Ti species and electron donor, as well as propylene polymerization over the Ziegler-Natta catalyst have been investigated using density functional theory （DFT） method. Twelve possible support models of regular and defective MgC12 （110） and （100） surfaces were built. The individual adsorptions of titanium chlorides as mononuclear or dinuclear, and ethyl benzoate （EB） as electron donor, on these models were evaluated. The analysis of energies presented the cases of EB adsorption were generally more stable than titanium chlorides on both surfaces. Thus, EB as internal electron donor mainly prevented TIC14 from coordinating on the MgC12 surfaces where mostly non-stereospecific active sites could be formed. Exceptionally, A5 the site model with terminal Cl-vacancy on the MgC12 support, presented stronger adsorption of TiCl4 than that of EB on （110） surface. Since the TIC14 and ethyl benzoate （EB） would compete to adsorb on the support surface, it seems reasonable to assume that TIC14 might predominately occupy this site, which can act as the most plausible active site for propylene polymerization. The first insertion of propylene monomer into the A5 active site model showed that it exhibited good regioselectivity but poor stereospecificity in the absence of electron donor.

关键词： Supported Ziegler-Natta catalyst Propylene polymerization Defective MgC12 surfaces Electron donor Densityfunctional theory.

Nuclear mass based on the multi-task learning neural network method

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Nuclear Science and Techniques 2022年第4期33卷 96-103页

作者： Xing-Chen Ming Hong-Fei Zhang rui-rui Xu Xiao-Dong Sun Yuan Tian Zhi-Gang ge School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China

The global nuclear mass based on the macroscopic-microscopic model was studied by applying a newly designed multi-task learning artificial neural network(MTL-ANN). First, the reported nuclear binding energies of 2095 nuclei(Z ≥ 8, N ≥ 8) released in the latest Atomic Mass Evaluation AME2020 and the deviations between the fitting result of the liquid drop model(LDM)and data from AME2020 for each nucleus were *** compensate for the deviations and investigate the possible ignored physics in the LDM, the MTL-ANN method was introduced in the model. Compared to the single-task learning(STL) method, this new network has a powerful ability to simultaneously learn multi-nuclear properties,such as the binding energies and single neutron and proton separation energies. Moreover, it is highly effective in reducing the risk of overfitting and achieving better predictions. Consequently, good predictions can be obtained using this nuclear mass model for both the training and validation datasets and for the testing dataset. In detail, the global root mean square(RMS) of the binding energy is effectively reduced from approximately 2.4 MeV of LDM to the current 0.2 MeV, and the RMS of Sn, Spcan also reach approximately 0.2 MeV. Moreover, compared to STL, for the training and validation sets, 3-9% improvement can be achieved with the binding energy, and 20-30% improvement for S_(n), S_(p);for the testing sets, the reduction in deviations can even reach 30-40%, which significantly illustrates the advantage of the current MTL.

关键词： Macroscopic–microscopic model Binding energy Neural network Multi-task learning

晚明灾疫应对中的基层政府运作——对万历十五年至十七年徽州府的考察

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古代文明（中英文） 2025年第1期19卷 128-141,M0007页

作者：葛俊超安徽师范大学历史学院安徽芜湖241000

地方政府的灾疫应对为观察基层治理结构的特殊案例。审视万历十五年至十七年南直隶徽州府灾疫:储备缺失与仓政废弛造成灾害破坏的持续释放,进而引发基层秩序紊乱。围绕资源的配置和获取,该府及所辖诸县积极与上级部门及周边地区政府进... 详细信息

地方政府的灾疫应对为观察基层治理结构的特殊案例。审视万历十五年至十七年南直隶徽州府灾疫:储备缺失与仓政废弛造成灾害破坏的持续释放,进而引发基层秩序紊乱。围绕资源的配置和获取,该府及所辖诸县积极与上级部门及周边地区政府进行互动。在自救无力、他救无望时,该府转而对域内社会力量进行全面动员,直接引导了基层社会的自我修复。该府的灾疫应对行为说明,在明朝晚期,基层政府仍在社会治理中扮演了主要角色。从灾疫处置视角切入基层社会,有助于走出“士绅社会”的定式思维,进一步丰富对帝制中国基层治理结构的认识。

关键词：晚明灾疫基层政府万历徽州

Effects of environmental humidity on the survival and development of pine caterpillars, Dendrolimus tabulaeformis （Lepidoptera： Lasiocampidae）

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Insect Science 2008年第2期15卷 147-152页

作者： rui-Dong Han Megha Parajulee Zhong He Feng ge State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing Weifang Forestry Bureau of Shandong Province Weifang City Shandong Province China Texas Agricultural Experiment Station Lubbock Texas USA

The pine caterpillar, Dendrolimus tabulaeformis is one of the most important pests on Pinus tabulaeformis and other pine species in North China. In the present study, effects of relative humidity （RH） on the development and survival of pine caterpillars and soil moisture （SM） on their diapausing larvae were investigated. Low RH （20%） deferred the development of eggs and larvae, reduced egg hatching and larval surviving compared to 40%, 60% and 80% RH. Both low （20%） and high （100%） RH reduced egg hatching, but only 20% RH deferred the development of larvae, prolonged developmental duration and reduced the body mass and body length of larvae. The SM influenced the survival of diapausing larvae significantly. The dry treatment significantly reduced the supercooling points （SCPs）, whereas increased the mortality and reduced body mass from 56.9 to 36.5 mg and body water content from 78% to 63% after 2 weeks＇ exposure. Therefore, higher RH is more favorable for the development of early instars and survival of diapausing larvae of the pine caterpillars.

关键词： cold hardiness Dendrolimus tabulaeformis development mortality relative humidit y

Maximum entropy searching

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CAAI Transactions on Intelligence Technology 2019年第1期4卷 1-8页

作者： rui Jiang Hui Zhou Han Wang Shuzhi Sam ge Institute for Future(IFF) Qingdao UniversityQingdao 266071People’s Republic of China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore

This study presents a new perspective for autonomous mobile robots path searching by proposing a biasing direction towards causal entropy maximisation during random tree *** entropy-biased rapidly-exploring random tree(ME-RRT)is proposed where the searching direction is computed from random path sampling and path integral approximation,and the direction is incorporated into the existing rapidly-exploring random tree(RRT)*** of ME-RRT including degenerating conditions and additional time complexity are also *** performance of the proposed approach is studied,and the results are compared with conventional RRT/RRT*and goal-biased approach in 2D/3D *** show that trees are generated efficiently with fewer iteration numbers,and the success rate within limited iterations has been greatly improved in complex environments.

关键词： ME-RRT RRT

贻贝启发接枝骨形态发生蛋白2成骨活性肽的介孔生物玻璃修复股骨髁缺损

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中国组织工程研究 2025年第22期29卷 4629-4638页

作者：俞磊张巍秦毅葛高然柏家祥耿德春苏州大学附属第一医院骨科江苏省苏州市215006

背景:骨形态发生蛋白2在胚胎发育、骨骼形成和再生修复中具有重要作用,但高剂量应用与癌症发病密切相关。骨形态发生蛋白2成骨活性段L20能够有效减少癌症等不良反应,并可显著促进骨组织再生。目的:将骨形态发生蛋白2活性肽段以贻贝衍生... 详细信息

背景:骨形态发生蛋白2在胚胎发育、骨骼形成和再生修复中具有重要作用,但高剂量应用与癌症发病密切相关。骨形态发生蛋白2成骨活性段L20能够有效减少癌症等不良反应,并可显著促进骨组织再生。目的:将骨形态发生蛋白2活性肽段以贻贝衍生肽模拟策略接枝在介孔生物玻璃表面,探究其对组织工程成骨性能的影响。方法:(1)采用模板法合成介孔生物玻璃纳米颗粒,采用一步法合成负载骨形态发生蛋白2成骨活性肽L20的介孔生物玻璃纳米颗粒,表征负载骨形态发生蛋白2成骨活性肽L20介孔活性玻璃纳米颗粒的形貌与体外缓释性能。(2)分离提取SD大鼠骨髓间充质干细胞,传2代后分别与PBS(空白组)、介孔生物玻璃纳米颗粒(对照组)、负载骨形态发生蛋白2成骨活性肽L20介孔生物玻璃纳米颗粒(实验组)共培养,采用细胞活死荧光染色和CCK-8法检测细胞毒性和细胞增殖,扫描电镜观察细胞黏附;成骨诱导分化后,进行碱性磷酸酶染色、茜素红S染色与成骨相关基因表达检测。(3)取15只SD大鼠,建立双侧股骨髁缺损模型,采用随机数字表法分为3组:空白组(n=5)不植入任何材料,对照组(n=5)植入介孔生物玻璃纳米颗粒,实验组(n=5)植入负载骨形态发生蛋白2成骨活性肽L20介孔生物玻璃纳米颗粒。术后8周,进行股骨Micro-CT扫描与组织形态观察。结果与结论:(1)扫描电镜下可见负载骨形态发生蛋白2成骨活性肽L20介孔生物玻璃纳米颗粒为球形、单分散颗粒,透射电镜下可见其具有多孔结构,平均粒径为(268.10±0.58) nm,体外可缓释L20。(2)负载骨形态发生蛋白2成骨活性肽L20介孔生物玻璃纳米颗粒无细胞毒性,并且可促进骨髓间充质干细胞的增殖与黏附;与空白组、对照组相比,实验组碱性磷酸酶活性与细胞外基质矿化能力均升高(P <0.05),碱性磷酸酶、Runx2、骨钙素mRNA表达升高(P <0.05)。(3)股骨Micro-CT扫描结果显示,与空白组、对照组相比,实验组新生骨量与骨密度均升高(P <0.05);苏木精-伊红与Masson染色结果显示,与空白组、对照组相比,实验组新骨生成与胶原纤维均增加。(4)结果表明,负载骨形态发生蛋白2活性肽L20介孔生物玻璃纳米颗粒具有良好的生物相容性及体内外促成骨性能,可促进SD大鼠股骨髁缺损的再生修复。

关键词：骨形态发生蛋白2成骨活性肽介孔生物玻璃纳米颗粒邻苯二酚成骨细胞分化股骨髁缺损骨组织工程生物材料