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Nano Research 2010年第5期3卷 350-355页

作者： hui cao Jing Ma Yi Luo Department of Theoretical Chemistry School of BiotechnologyRoyal Institute of TechnologyS-10691 StockholmSweden School of Chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of Ministry of EducationNanjing UniversityNanjing 210093China

We have combined molecular dynamics simulations with first-principles calculations to study electron transport in a single molecular junction of perylene tetracarboxylic diimide (PTCDI) in aqueous solution under external electric gate fields. It is found that the statistics of the molecular conductance are very sensitive to the strength of the electric field. The statistics of the molecular conductance are strongly associated with the thermal fluctuation of the water molecules around the PTCDI molecule. Our simulations reproduce the experimentally observed three orders of magnitude enhancement of the conductance, as well as the temperature dependent conductance, under the electrochemical gates. The effects of the molecular polarization and the dipole rearrangement of the aqueous solution are also discussed.

关键词： Molecular junction field effect solvent effect temperature effect statistical behavior

Calibrating Photometric Redshift Measurements with the Multi-channel Imager(MCI) of the China Space Station Telescope(CSST)

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Research in Astronomy and Astrophysics 2022年第2期22卷 204-214页

作者： Ye cao Yan gong Zhen-Ya Zheng Chun Xu Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China Science Center for China Space Station Telescope National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryShanghai 200030China Division of Optical Astronomical Technologies Shanghai Astronomical ObservatoryShanghai 200030China Joint Center of SHAO and SITP for Infrared Astronomical Instrumentation Shanghai Astronomical ObservatoryShanghai 200030China

The China Space Station Telescope(CSST) photometric survey aims to perform a high spatial resolution(~0.″ 15)photometric imaging for the targets that cover a large sky area(~17,500 deg^(2)) and wide wavelength range(from NUV to NIR). It expects to explore the properties of dark matter, dark energy, and other important cosmological and astronomical areas. In this work, we evaluate whether the filter design of the Multi-channel Imager(MCI), one of the five instruments of the CSST, can provide accurate photometric redshift(photoz) measurements with its nine medium-band filters to meet the relevant scientific objectives. We generate the mock data based on the COSMOS photometric redshift catalog with astrophysical and instrumental effects. The application of upper limit information of low signal-to-noise ratio data is adopted in the estimation of photoz. We investigate the dependency of photoz accuracy on the filter parameters, such as band position and width. We find that the current MCI filter design can achieve good photoz measurements with accuracy σ_(z)■ 0.017 and outlier fraction f_(c)■ 2.2%. It can effectively improve the photoz measurements of the main CSST survey using the Survey Camera to an accuracy σ_(z)■ 0.015 and outlier fraction f_(c)■ 1.5%. This indicates that the original MCI filters are proper for the photoz calibration.

关键词： cosmology:observations (cosmology:)large-scale structure of universe galaxies:distances and redshifts

Electronic Structure of KFe_(2)Se_(2) from First-Principles Calculations

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Chinese Physics Letters 2011年第5期28卷 230-233页

作者： cao Chao DAI Jian-hui Condensed Matter Physics Group Department of PhysicsHangzhou Normal UniversityHangzhou 310036 Zhejiang Institute of Modern Physics Department of PhysicsZhejiang UniversityHangzhou 310027

Electronic structures and magnetic properties for iron-selenide KFe_(2)Se_(2) are studied by first-principles *** ground state is collinear antiferromagnetic with calculated 2.26μB magnetic moment on Fe atoms;and the J_(1)and J_(2) coupling strengths are calculated to be 0.038eV and *** states around EF are dominated by the Fe 3d orbitals which hybridize noticeably to the Se 4p *** the band structure of KFe_(2)Se_(2) is similar to a heavily electron-doped BaFe_(2)As_(2) or FeSe system,the Fermi surface of KFe_(2)Se_(2) is much closer to the FeSe system since the electron sheets around M are symmetric with respect to x-y *** features,as well as the absence of Fermi surface nesting,suggest that the parent KFe_(2)Se_(2) could be regarded as an electron doped FeSe system with possible local moment magnetism.

关键词： system Fermi moment

LEACHING GOLD BY LOW CONCENTRATION THIOSULFATE SOLUTION

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Transactions of Nonferrous Metals Society of China 1992年第4期2卷 21-25页

作者： cao Changlin Hu Jiexue gong Qian Institute of Chemical Metallurgy Academia SinicaBeijing 100080China

The effects of the concentrations of thiosulfate,copper and ammonia on the extraction of gold from sulfide gold concentrate have been *** results show that it is possible to reduce thiosulfate *** than 95%of the gold could be extracted by a 0.2 mol/L thiosulfate leaching solution in two hours under suitable ***,the process of washing the residue was simplified,and the consumption and loss of thiosulfate carried by the washing residue were reduced.

关键词： gold extraction thiosulfate sulfide ore

FUNDAMENTAL SOLUTION BASED GRADED ELEMENT MODEL FOR STEADY-STATE HEAT TRANSFER IN FGM

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Acta Mechanica Solida Sinica 2012年第4期25卷 377-392页

作者： Leilei cao hui Wang Qing-Hua Qi Key Laboratory for Highway Construction Technology and Equipment of Ministry of Education Chang'an University Xi'an 710064 China School of Engineering Australian National University canberra ACT 0200 Australia College of Civil Engineering and Architecture Henan University of Technology Zhengzhou 450052 China

A novel hybrid graded element model is developed in this paper for investigating thermal behavior of functionally graded materials （FGMs）. The model can handle a spatially varying material property field of FGMs. In the proposed approach, a new variational functional is first constructed for generating corresponding finite element model. Then, a graded element is formulated based on two sets of independent temperature fields. One is known as intra-element temperature field defined within the element domain; the other is the so-called frame field defined on the element boundary only. The intra-element temperature field is constructed using the linear combination of fundamental solutions, while the independent frame field is separately used as the boundary interpolation functions of the element to ensure the field continuity over the interelement boundary. Due to the properties of fundamental solutions, the domain integrals appearing in the variational functional can be converted into boundary integrals which can significantly simplify the calculation of generalized element stiffness matrix. The proposed model can simulate the graded material properties naturally due to the use of the graded element in the finite element （FE） model. Moreover, it inherits all the advantages of the hybrid Trefftz finite element method （HT-FEM） over the conventional FEM and boundary element method （BEM）. Finally, several examples are presented to assess the performance of the proposed method, and the obtained numerical results show a good numerical accuracy.

关键词： graded element hybrid FEM heat conduction functionally graded materials

Rapid synthesis of oxygen-defected molybdenum oxides quantum dots as efficient nanozymes for healing diabetic ulcers

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Nano Research 2024年第7期17卷 6376-6385页

作者： Fangjun cao hui Feng Jiaxin Yao Xiang Hou Tiezhi Jin Junfeng hui Shaanxi Key Laboratory of Qinling Ecological Security Shaanxi Institute of ZoologyXi’an 710072China Engineering Research Center of Western Resource Innovation Medicine Green Manufacturing Ministry of EducationSchool of Chemical EngineeringNorthwest UniversityXi'an 710069China Shaanxi Key Laboratory of Degradable Biomedical Materials and Shaanxi R&D Center of Biomaterials and Fermentation Engineering School of Chemical EngineeringNorthwest UniversityXi'an 710069China

The continuous inflammatory response in diabetic skin wounds leads to excessive production of reactive oxygen species,which cause a vicious circle of long-term *** the therapeutic research of metal nanoenzymes for healing diabetic ulcers,it still faces the challenges in poor nanoenzymes activity and low-efficient therapeutic ***,ultrasmall oxygen-deficient MoO_(3−X)quantum dots were fabricated and employed as nanoenzymes for healing fiabetic *** PEGylation,PEGylated MoO_(3−X)quantum dots(MoO_(3−X)/PEG)with oxygen vacancies exhibits excellent photothermal,peroxidase/catalase-like *** addition,these MoO_(3−X)/PEG showed superior properties in scavenging H_(2)O_(2)and effectively inhibiting the scavenging of reactive oxygen *** importantly,such an oxygen-defected MoO_(3−X)/PEG had obvious antibacterial and skin repairing effects on alleviating hypoxia and excessive oxidative stress even in a mouse model of diabetic ulcers,inhibiting proinflammatory cytokines and significantly accelerating the healing of infected wounds,which shows great application potential for promoting wound *** work highlights that the developed oxygen defected molybdenum oxide compounds capable of peroxidaselike and catalase-like activities show great application potential for healing diabetes wound.

关键词： oxygen-defected molybdenum-based nanoenzymes antioxidant anti-inflammatory diabetes ulcer wounds

Discrete Numerical Study on Type II Fracture of Partially Detached Concrete Panels in Cold Region

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Structural Durability & Health Monitoring 2025年第1期19卷 167-191页

作者： Huayi Zhang Maobin Song Lei Shen Nizar Faisal Alkayem Maosen cao College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210024China Haihe River Huaihe River and Xiaoqinghe River Basin Water Conservancy Management and Service Center of Shandong ProvinceJinan250100China College of Mechanics and Engineering Science Hohai UniversityNanjing211100China

When the upper chord beam of the beam-string structure(BSS)is made of concrete-ﬁlled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the *** order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during con-struction,the inﬂuence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefﬁcient on the bending stiffness are analyzed parametrically by the numerical simula-tion technology based on an actual *** calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical ***,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction ***,the optimal construction plan of concrete placementﬁrst and then prestress-tensioning is proposed.

关键词： Beam-string structure(BSS) concrete-ﬁlled steel tube(CFST) bending stiffness timing of concrete placement prestress-tensioning

Impact of ventilation design on the precooling effectiveness of horticultural produce-a review

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Food Quality and Safety 2020年第1期4卷 29-40页

作者： Yuhui cao Ya-Fang gong Xin-Rong Zhang College of Engineering Sciences University of Chinese Academy of SciencesBeijingChina Department of Energy and Resource Engineering College of EngineeringPeking UniversityBeijingChina

Optimizing the ventilation design of packaging system is of crucial importance for improving the efficiency of the forced-air precooling process to maintain the quality of horticultural produce and extend the shelf life in food cold *** efforts had been devoted to the study about the impact of ventilation design on airflow and temperature distribution inside ventilated *** paper reviews relevant research methods,commonly used quantities for the measurement of precooling effectiveness,attractive design parameters,and their impact on precooling *** allow us to know exactly the characteristic and deficiency of each research method,identify dominant design parameters,and seek a promising way for the future improvement of the ventilated packaging system.

关键词： horticultural produce precooling effectiveness ventilation design forced-air precooling technique packaging system

Regulation of surface carbides on palladium nanocubes with zeolitic imidazolate frameworks for propyne selective hydrogenation

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Nano Research 2021年第5期14卷 1559-1564页

作者： Linzhong Wu Mingyu Chu Jin gong Muhan cao Yu Liu Yong Xu Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversityNo.199 Ren’ai RoadSuzhou215123China Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage Devices Collaborative Innovation Center of Advanced Energy MaterialsSchool of Materials and EnergyGuangdong University of TechnologyGuangzhou510006China

The selective hydrogenation of propyne to propylene has attracted great attention in chemical industry for removing trace amount of propyne for producing polymer-grade propylene. As the state-of-the-art catalyst, Pd suffers from the disadvantage of poor propylene selectivity due to the over-hydrogenation of propylene to propane. We here demonstrate that Pd nanocubes (NCs) coated by zeolitic imidazolate frameworks (i.e., Pd NCs@ZIF-8) can serve as highly active and selective catalysts for propyne selective hydrogenation (PSH). Benefitting from the unique properties and abundant groups of ZIF-8, Pd carbide (Pd-C) is formed on the surface of Pd NCs after thermal treatment, which acts the active sites for PSH to propylene. More importantly, the content of Pd-C can be precisely controlled by altering the calcination temperature without aggregation of Pd NCs and obvious changes in the framework of ZIF-8. The formation of Pd-C on Pd NCs@ZIF-8 can strongly suppress the H2 adsorption, and thus selectively catalyze propyne to propylene. Consequently, the optimized catalyst (i.e., Pd NCs@ZIF-8-100) exhibits a propylene selectivity of 96.4% at a propyne conversion of 93.3% at 35 °C and atmospheric pressure. This work may not only provide an efficient catalyst for PSH, but also shed a new light on the catalytic application of ZIFs.

关键词： propyne selective hydrogenation Pd nanocubes zeolitic imidazolate frameworks core-shell nanostructures Pd carbide

A clinical study to determine the threshold of bronchodilator response for diagnosing asthma in Chinese children

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World Journal of Pediatrics 2019年第6期15卷 559-564页

作者： Xiao-hui Kang Wan Wang Ling cao Children's Hospital Affiliated to the Capital Institute of Pediatrics No.2 Ya bao RoadChaoyang DistrictBeijingChina Shanxi Provincial Children's Hospital TaiyuanChina

Background There is few objective,clinically feasible and inexpensive test for diagnosing childhood *** want to find an ideal way to solve *** The control group was 301 non-asthmatic children,and the asthma group was 286 asthmatic *** asthmatic children were divided into three groups according to the severity of their ***-and post-bronchodilator spirometer tests were performed,and the main spirometer parameters were *** bronchodilator response(BDR)[BDR is used to determine the reversibility of airway obstruction by measuring the changes of forced expiratory volume in the first second(FEV1)before and after inhalation of bronchodilators]was then determined,and the optimal threshold of BDR for diagnosing childhood asthma was *** 301 non-asthmatic children and 286 asthmatic children participated in the study,the demographics were *** 1 for pre-bronchodilator of asthmatic children was significantly lower than that of non-asthmatic children(P≤0.01).BDR of non-asthmatic children was 3.30±3.85%.BDR of asthmatic children was 9.45±9.15%.There was no significant difference in BDR for patients with different severities of asthma within the *** had no statistical correlation with gender,age,height,weight in neither non-asthmatic children nor asthmatic *** the receiver-operating characteristic curve,a BDR threshold of≥7.5%offered an optimal balance in asthma diagnosis with a sensitivity rate of 50.7%and specificity rate of 87.7%.Meanwhile,with a BDR threshold of≥12%,the sensitivity rate was 28.7%and the specificity rate was 96.3%.Conclusion A BDR threshold of≥7.5%has more value in childhood asthma diagnosis as compared to≥12%.

关键词： Asthma diagnosis Bronchodilator response Threshold