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Journal of Thermal Science 2022年第3期31卷 663-677页

作者： zhao Xiaoyan YAN Suying ZHANG Na zhao Ning GAO Hongwei College of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010051China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

The linear Fresnel reflector concentrator(LFRC)is widely used in the field of solar energy utilization due to its simple structure,low cost,and excellent wind ***,the LFRC operates outdoors all year round,and the dust accumulation on the mirror will reduce the optical efficiency of the system,so it needs to be perfected and *** this paper,a focal plane energy flux experimental device was designed to test the energy flux of the system under different dust accumulation *** results indicate that,the dust density on the mirror increased and the energy flux on the focal plane decreased with increase of dust accumulation *** undergoing dust accumulation for 35 days,the dust density on the mirror reached 4.33 g/m^(2)and the average energy flux on the focal plane decreased to 1.78 kW/m^(2).Additionally,the variation of reflectivity caused by dust accumulation on mirror was taken as the quantitative index,and a prediction model for the impact of dust on the optical efficiency of the system was *** results will provide guidance for improving the optical efficiency of the LFRC.

关键词： dust accumulation energy flux linear Fresnel reflector concentrator optical efficiency forecast

High-fidelity simulation of blade vortex interaction of helicopter rotor based upon TENO scheme

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Chinese Journal of Aeronautics 2023年第10期36卷 275-292页

作者： Wei BIAN Guoqing zhao Xi CHEN Bo WANG qijun zhao National Key Laboratory of Rotorcraft Aeromechanics College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Numerical simulation methods for unsteady vortex field of helicopter rotor with high resolution and low dissipation TENO8-AA primitive variables reconstruction schemes are established based on moving-embedded grid and Navier-Stokes ***,the Targeted Essentially Non-Oscillatory(TENO)scheme are developed by employing ENO-like candidate stencil selection strategy,and the candidate stencil is adopted with optimal weight in smooth region while it is discarded completely in discontinuous region,which reduces the dissipation and dispersion errors and approaches better spectral ***,the aerodynamic characteristics of Helishape-7A model rotor in Blade Vortex Interaction(BVI)state and the flowfield of Lynx rotor in hover are simulated,which validates that the blade tip vortex trajectory with larger wake age and more details of vortex can be captured by TENO8-AA scheme with only a quarter of grid points and half time comparing to WENO-JS ***,the simulation accuracy of thrust coefficient is improved by up to 36%.Finally,the analyses for BVI and aeroacoustic characteristics of Operational Loads Survey(OLS)rotor are conducted,and the different forms of interaction mechanism are explored,such as oblique and parallel *** results indicate that TENO scheme not only ensures the resolution of simulation in discontinuous region,but also minimizes the numerical dissipation in smooth region dominated by blade tip ***,the acoustic pressure peak prediction error of rotor in BVI state is significantly reduced to 5.6%and 0.8%at two microphone locations,respectively.

关键词： Aeroacoustics Blade tip vortex Blade vortex interaction Helicopter rotor TENO scheme

Temperature-induced Lifshitz transition in topological insulator candidate HfTe_5

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Science Bulletin 2017年第13期62卷 950-956页

作者： Yan Zhang Chenlu Wang Guodong Liu Aiji liang Lingxiao zhao Jianwei Huang qiang Gao Bing Shen Jing Liu Cheng Hu Wenjuan zhao Genfu Chen Xiaowen Jia Li Yu Lin zhao Shaolong He Fengfeng Zhang Shenjin Zhang Feng Yang Zhimin Wang qinjun Peng Zuyan Xu Chuangtian Chen Xingjiang Zhou Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center of Quantum Matter Military Transportation University Technical Institute of Physics and Chemistry Chinese Academy of Sciences

The ongoing discoveries and studies of novel topological quantum materials have become an emergent and important field of condensed matter physics. Recently, Hfres ignited renewed interest as a candidate of a novel topological material. The single-layer Hffes is predicted to be a tWOldimensional large band gap topological insulator and can be stacked into a bulk that may host a temperatureldriven topological phase transition. Historically, Hfres attracted considerable interest for its anomalous transport properties characterized by a peculiar resistivity peak accompanied by a sign reversal carrier type. The origin of the transport anomaly remains under a hot debate. Here we report the first high-resolution laserlbased anglelresolved photoemission measurements on the temperature-dependent electronic structure in Hffes. Our results indicated that a temperature-induced Lifshitz transition occurs in Hffes, which provides a natural understanding on the origin of the transport anomaly in Hffe~. In addition, our observa- tions suggest that Hffes is a weak topological insulator that is located at the phase boundary between weak and strong topological insulators at very low temperature.

关键词： HtTe5 ZrTe5 Lifshitz transition Topological insulators Angle-resolved photoemission spectroscopy(ARPES)

Risk factors for hypospadias in China

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Asian Journal of Andrology 2014年第5期16卷 778-781,I0011页

作者： Ling-Fan Xu Chao-zhao liang Julia Lipianskaya Xian-Guo Chen Song Fan Li Zhang Jun Zhou Sheng Tai Chang-qin Jiang Department of Urology The First Affiliated Hospital of Anhui Medical University Hefei China Department of Pathology David Geffen School of Medicine at UCLA Los Angeles CA USA

This case-controlled study was designed to evaluate the association between various baseline parental factors and the risk of hypospadias in China. Patients were selected from tertiary referral hospitals in Anhui, a province in mid-eastern China. A questionnaire was given to the parents of each patient. The final database included 193 cases and 835 controls. The incidence of additional coexistent anomalies was 13.0%, primarily cryptorchidism （9.8%）. Ten patients （5.1%） were from families with genital anomaly, including five families （2.6%） with hypospadias. The risks of hypospadias was higher for children of mothers 〉 35 （odds ratio [OR] =1.47） and 〈 18 （OR = 2.95） years of age, and in mothers who had consumed alcohol （OR = 2.67）, used drugs （OR = 1.53） and had an infection （OR = 1.87） during pregnancy. The risk of hypospadias was also higher when mothers （OR = 1.68） and fathers （OR = 1.74） were engaged in agriculture. Other factors assessed were not associated with the risk of hypospadias.

关键词： genetics hypospadias maternal exposures paternal exposures pregnancy risk factors

Rnf20 deficiency in adipocyte impairs adipose tissue development and thermogenesis

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Protein & Cell 2021年第6期12卷 475-492页

作者： Xiaojuan liang Cong Tao Jianfei Pan Lilan Zhang Lulu Liu Ying zhao Yiping Fan Chunwei Cao Jiali Liu Jin Zhang Sin Man Lam Guanghou Shui Wanzhu Jin Wei Li Jianguo zhao Kui Li Yanfang Wang State Key Laboratory of Animal Nutrition Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China Department of Animal Science China Agricultural UniversityBeijing 100193China Institute of Zoology Chinese Academy of SciencesBeijing 100101China College of Biological Chemical Sciences and EngineeringJiaxing UniversityJiaxing 314001China Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China College of Life Sciences Qingdao Agricultural UniversityQingdao 266109China

RNF20,an E3 ligase critical for monoubiquitination of histone H2B at lysine 120(H2Bub),has been implicated in the regulation of various cellar processes;however,its physiological roles in adipocytes remain poorly ***,we report that the adipocyte-specific knockout of Rnf20(ASKO)in mice led to progressive fat toss,organomegaly and *** signs of hyperinsulinemia,normal insulin sensitivity and improved glucose tolerance were observed in the young and aged CD-fed ASKO *** addition,high-fat diet-fed ASKO mice developed severe liver ***,we observed that the ASKO mice were extremely sensitive to a cold environment due to decreased expression levels of brown adipose tissue(BAT)selective genes,including uncoupling protein 1(l/cpf),and impaired mitochondrial *** decreased levels of peroxisome proliterator-activated receptor gamma(Ppary)were observed in the gonadal white adipose tissues(gWAT)from the ASKO mice,suggesting that Rnf20 regulates adipogenesis,at least in part,through ***-treated ASKO mice exhibited increased fat mass compared to that of the non-treated ASKO ***,our results illustrate the critical role of RNF20 in control of white and brown adipose tissue development and physiological function.

关键词： RNF20 fat loss adipose tissue development thermogenesis

Improvement on Temperature Measurement of Cold Atoms in a Rubidium Fountain

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Chinese Physics Letters 2011年第6期28卷 90-93页

作者： LÜDe-Sheng QU qiu-Zhi WANG Bin zhao Jian-Bo LIU liang WANG Yu-Zhu Key Laboratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

The time-of-flight(TOF)method is one of the most common ways to measure the temperature of cold *** the cold atomic fountain setup,the geometry of the probe beam will introduce the measurement errors to the spatial distribution of cold atomic cloud,which will lead to the measurement errors on atomic *** deconvolution,we recover the atomic cloud profile from the TOF ***,we use the recovered signals other than the TOF signals to obtain a more accurate atomic *** will be important in estimating the effects of cold atom collision shift and the shift due to transverse cavity phase distribution on an atomic fountain clock.

关键词： temperature atomic distribution

Perovskite/silicon-based heterojunction tandem solar cells with 14.8%conversion efficiency via adopting ultrathin Au contact

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Journal of Semiconductors 2017年第1期38卷 60-65页

作者： Lin Fan Fengyou Wang Junhui liang Xin Yao Jia Fang Dekun Zhang Changchun Wei Ying zhao Xiaodan Zhang Institute of Photo-Electronic Thin Film Devices and Technology of Nankai University Key Laboratory of Photo-Electronic Thin Film Devices and TechnologyTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

A rising candidate for upgrading the performance of an established narrow-bandgap solar technology without adding much cost is to construct the tandem solar cells from a crystalline silicon bottom cell and a high open-circuit voltage top ***,we present a four-terminal tandem solar cell architecture consisting of a selffiltered planar architecture perovskite top cell and a silicon heterojunction bottom cell.A transparent ultrathin gold electrode has been used in perovskite solar cells to achieve a semi-transparent *** transparent ultrathin gold contact could provide a better electrical conductivity and optical reflectance-scattering to maintain the performance of the top cell compared with the traditional metal oxide *** four-terminal tandem solar cell yields an efficiency of 14.8%,with contributions of the top（8.98%）and the bottom cell（5.82%）,*** also point out that in terms of optical losses,the intermediate contact of self-filtered tandem architecture is the uppermost problem,which has been addressed in this communication,and the results show that reducing the parasitic light absorption and improving the long wavelength range transmittance without scarifying the electrical properties of the intermediate hole contact layer are the key issues towards further improving the efficiency of this architecture device.

关键词： lanar perovskite top cell silicon heterojunction bottom cell four-terminal tandem transparent ultra-thin gold electrode

Why Did the Reform Fail?The Impact of the Personnel System Reform on Teachers in Jia County of China

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Sino-US English Teaching 2019年第12期16卷 491-509页

作者： zhao qian JIAO Xinran liang Yuwei Beijing Normal University BeijingChina Beijing Dance Academy BeijingChina

Over recent years,the reform-driven development of education has been one primary idea of the Chinese government under the leadership of Xi *** all,the reform of the personnel system,closely related to the interests of teachers,becomes the most sensitive link in the educational *** root out the restriction of education system on teachers and enhance their enthusiasm for work,Jia County carried out a reform of teacher personnel system from 2013 to 2016,including breaking the hierarchical restriction on teachers’administrative promotion,decentralizing the power of confirming the teachers’professional titles,eliminating the teachers with the worst performances,practicing performance salary,and other *** this study,we tracked 627 teachers regarding their work enthusiasm and stress during the three-year reform,analyzed the data through the Hierarchical Linear Model(HLM),and found that:(1)The teachers’enthusiasm for work increased over time,but did not significantly change with the consideration of the influence of the principals’leadership in *** personnel system reform aiming at motivating teachers failed to work as expected.(2)The teachers’work stress still increased year by ***,this study concludes that the reform in Jia County failed to fulfill its goals and that the vigorous top-down reform did not lead to ideal results.A reason might be that the reform damaged the vested interests of teachers who represent the deep-rooted nepotism typically in the Chinese education *** of educational personnel system should give schools a full play regarding educational governance in the future.

关键词： county-level reform teacher work stress teacher work enthusiasm tracking data

Precipitation Behavior and Microstructural Evolution of Ferritic Ti–V–Mo Complex Microalloyed Steel

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Acta Metallurgica Sinica(English Letters) 2018年第9期31卷 997-1005页

作者： Ke Zhang Hui Wang Xin-Jun Sun Feng-Li Sui zhao-Dong Li En-Xiang Pu Zheng-Hai Zhu Zhen-Yi Huang Hong-Bo Pan qi-Long Yong Key Laboratory of Metallurgical Emission Reduction and Resources Recycling Anhui University of TechnologyMinistry of EducationMaanshan 243032China School of Metallurgical Engineering Anhui University of TechnologyMaanshan 243032China Central Iron and Steel Research Institute Beijing 100081China

Precipitation behavior of （Ti, V, Mo）C and microstructural evolution of the ferritic Ti-V-Mo complex microalloyed steel were investigated through changing coiling temperature （CT）. It is demonstrated that the strength of the Ti-V-Mo microalloyed steel can be ascribed to the combination of grain refinement hardening and precipitation hardening. The variation of hardness （from 318 to 415 HV, then to 327 HV） with CT （from 500 to 600-625 ℃, then to 700 ℃） was attributed to the changes of volume fraction and particle size of （Ti, V, Mo）C precipitates. The optimum CT was considered as 600-625 ℃, at which the maximum hardness value （415 HV） can be obtained. It was found that the atomic ratios of Ti, V and Mo in （Ti, V, Mo）C carbides were changed as the CT increased. The precipitates with the size of 〈 10 nm were the V-rich particles at higher CT of 600 and 650 ℃, while the Ti-rich particles were observed at lower CT of 500 and 550 ℃. Theoretical calculations indicated that the maximum nucleation rate of （Ti, V, Mo）C in ferrite matrix occurred around 630 ℃, which was consistent with the 625 ℃ obtained from experiment results.

关键词： Nano-sized precipitates Precipitation hardening Ti-V-Mo Coiling temperature Ferrite

中国-东盟跨境数据流动治理合作:现实与路径选择

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南洋问题研究 2024年第3期 85-98页

作者：赵祺云南大学马克思主义学院云南昆明650091 云南大学“一带一路”研究院云南昆明650091

跨境数据治理是中国与东盟深化数字经济合作的关键议题。基于文本分析法,可以发现东盟国家的跨境数据治理模式大体上有3种类型,同时东盟正努力打造相对统一的跨境数据治理规范体系。从“政策-市场-规则”的框架出发,中国与东盟跨境数据... 详细信息

跨境数据治理是中国与东盟深化数字经济合作的关键议题。基于文本分析法,可以发现东盟国家的跨境数据治理模式大体上有3种类型,同时东盟正努力打造相对统一的跨境数据治理规范体系。从“政策-市场-规则”的框架出发,中国与东盟跨境数据治理合作,虽然存在数字合作逐渐制度化、数字企业不断深耕东南亚市场、数据治理理念趋同等有利条件,但也面临东盟国家跨境数据治理规则相对复杂、美国对东盟国家的说服和拉拢、地区跨境数据治理“规则拥堵”等制约因素。未来双方应深化跨境数据治理合作,致力于打造中国—东盟网络空间命运共同体。

关键词：数字经济跨境数据治理中国—东盟关系

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