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PCB环保过滤芯的开发及应用

印制电路信息 2013年第S1期21卷 125-130页

作者：陈世荣罗小虎易国斌林克梅领亮吴国芳唐先明盛周林广东工业大学广东广州510006 广东正业科技股份有限公司广东东莞523808

文章介绍了开发PCB环保过滤芯的目的和意义,讨论了环保过滤芯的技术指标、生产工艺以及在PCB制造过程中的应用。

关键词：印制电路板过滤芯环境保护

An alternative aqueous synthetic route to preparing CdTe quantum dots with tunable photoluminescence

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Chinese Chemical Letters 2012年第3期23卷 359-362页

作者： Yi lin Wang sheng Yan Liu Li Ya zhou School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

An aqueous synthetic route has been developed for the preparation of mercaptosuccinic acid（MSA）-capped CdTe quantum dots （QDs） using TeO_2 as tellurium source and sodium borohydride as *** size and the emission color of CdTe QDs can be tuned by varying the reflux *** obtained QDs were characterized by photoluminescence（PL） spectroscopy,X-ray powder diffraction（XRD） and high-resolution transmission electron microscopy（HRTEM）.The results show that the CdTe QDs were of zinc-blende crystal structure in a sphere-like shape.

关键词： Cadmium telluride Quantum dots Synthesis Photoluminescence

Protective Effect of Human Umbilical Cord Mesenchymal Stem Cells in Glucocorticoid-induced Osteonecrosis of Femoral Head

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Current Medical Science 2021年第5期41卷 909-915页

作者： Chen QIU Jian-lin zhou Shuang DENG lin-sheng LONG Hao PENG Department of Orthopedics Renmin Hospital of Wuhan UniversityWuhan 430060China Department of Orthopedics Xiangyang No.1 People's HospitalHubei University7 of MedicineXicingyang 443000China

Objective:To evaluate the effect of human umbilical cord mesenchymal stem cells(hUC-MSCs)on preventing rats from glucocorticoid-induced osteonecrosis of femoral head(GC-ONFH)in the early stage in vivo and to investigate the possible mechanism of hUC-MSCs in regulating the balance of osteogenesis and ***:All rats were randomly divided into 3 groups:control group(C group),model group(M group),and intervention group(Ⅰ group).The model of GC-ONFH was developed by a sequential administration of lipopolysaccharide and *** rats in the Ⅰ group were treated with caudal vein injection of *** weeks later,the blood samples were obtained to measure the activity of alkaline phosphatase(ALP)and the content of triglyceride(TG)in serum,and the femoral heads were harvested and observed by hematoxylin-eosin staining,Micro-CT,Western blot and real-time quantitative polymerase chain ***:After intervention of hUC-MSCs,the necrosis rate of femoral head decreased from 83%(10/12)to 33%(4/12),the rate of empty bone lacuna was significantly decreased,the activity of ALP increased significantly,the content of TG decreased significantly,the bone density increased obviously,the expression of RUNX2 and Col Ⅰ increased significantly and the expression of PPARγ decreased ***:These results revealed that caudal vein injection of hUC-MSCs can effectively reduce the incidence of GC-ONFH in rats by increasing ALP activity and reducing TG content in serum,increasing bone mineral density,promoting the expression of RUNX2 and Col I,and inhibiting the expression of PPARγ.

关键词： glucocorticoid-induced osteonecrosis of femoral head human umbilical cord mesenchymal stem cell RUNX2,ColⅠ,PPARγ

Experimental and numerical investigations of the mechanical behavior of half sandwich laminate in the context of blanking

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Advances in Manufacturing 2020年第2期8卷 177-188页

作者： sheng Cai lin Chen Department of V ehicle Engineering College of EngineeringChina Agricultural UniversityBeijing 100083People's Republic of China CW Bearing GmbH Hamburg 22113Germany

In this study,the complex mechanical behavior of an aluminum/low-density polyethylene(LDPE)half sandwich structure was investigated during the blanking *** tests were conducted for the polymer and metal layer and the delamination behavior of the adhesive between the two layers.A new testing device was designed for detecting the delamination under tensile *** finite element models were established for the mechanical tests of the metal layer and the delamination of both layers for inverse parameter *** parameters for Lemaitre-type damage,Drucker-Prager,and cohesive zone modeIs were identified for the metal,polymer,and adhesive,respectively.A finiteelement(FE)model was established for the blanking process of the sandwich *** experimental forcedisplacement curves,obtained in the blanking process of the half sandwich sheet,were compared with the predicted results of the FE *** results showed that the predicted force-displacement curves and the experimental results were in good ***,the correlation between cutting clearance and changes in the forcedisplacement curves was *** feature values quantitatively described the imperfection of the experimental cutting *** effect of punch clearance on these values was studied numerically and *** results indicated that a smaller clearance generated a better cutting-edge *** stress state of the half sandwich structure during blanking was analyzed using the established FE model.

关键词： Sandwich plates Blanking Continuum damage mechanics(CDM) Drucker-Prager model Cohesive zone model

Parameter identification and blanking simulations of DP1000 and Al6082-T6 using Lemaitre damage model

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Advances in Manufacturing 2021年第3期9卷 457-472页

作者： sheng Cai lin Chen Department of Vehicle Engineering College of EngineeringChina Agricultural UniversityBeijing100083People’s Republic of China CW Bearing GmbH 22113HamburgGermany

This work provides numerical and experimental investigations of blanking process,where the shear-enhanced Lemaitre’s damage model is fully characterized and successfully applied in blanking process to predict the cutting force and cutting edge geometry under different blanking process *** high strength steel DP1000 and an aluminum alloy Al6082-T6 are selected for series of *** obtain the damage parameters in Lemaitre’s damage model the flat rectangular notched specimens tensile test was conducted and the inverse parameter identification procedure was *** characterizing the crack closure parameter h in the shear enhanced Lemaitre’s damage model,an in-plane torsion test with novel specimen design was *** finite element model(FEM)of this test was established with the minimum mesh size of 0.01 mm which was consistent with the minimum mesh size in the shear zone of the FEM for blanking process *** longitudinal strain distributions of four kinds of initial notch radius or central-hole specimen were measured and compared with simulation results to validate the FEMs for these four *** analysis of blanking of a circular work piece also was performed under three *** effects of blanking conditions on sheared part morphology were *** triaxiality distribution of the blank sheet was revealed taking advantage of the successfully established *** availability of the testing method and the determination method of the parameters was investigated.

关键词： Blanking Lemaitre damage model Stress triaxiality Finite element model(FEM)

Relationships Between Intensity Gradation and Evolution of Soil Erosion: A Case Study of Changting in Fujian Province, China

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Pedosphere 2012年第2期22卷 243-253页

作者： lin Chen zhou sheng-Lu WU Shao-Hua LIAO Fu-Qiang School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093(China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) School of Geography and Environment Jiangxi Normal UniversityNanchang 330022(China)

Soil erosion gradation is a robust and objective quantitative indicator of soil erosion intensity. Recent applications of soil erosion gradation have focused on monitoring soil erosion with models or simulation of soil erosion through gradation trends. However, soil erosion simulation accuracy is generally being reduced due to the rare consideration of the relationship between soil erosion gradation and erosion evolution. In this study, we investigated different soil erosion intensity grades to demonstrate their sensitivity to types and rates of erosion. Specifically, the objective was to define the relationship between soil erosion gradation and soil erosion evolution in Changting, an undeveloped area in Fujian Province, China, for four time intervals (1975, 1990, 1999, and 2006). The time series of erosion gradation were developed by modeling analysis with integration of several erosion indicators, and the relationships between the erosion grades and evolution types and rates were quantified. Comparison of the collapsing forces with natural and restoring forces based on human activity demonstrated that there existed an obvious spatial uncertainty in the erosion evolution types, both positive and negative succession coexisted, and the evolution rates were mostly influenced by the force of policy orientation. The impacts of these driving forces were eventually reflected in the erosion intensity gradation and erosion evolution. The correlation between the negative succession rate and erosion intensity gradation was weak and showed a poor contribution to the average succession rate, while the negative correlation between the positive succession rate and erosion intensity gradation would be increasingly clear as time passed.

关键词： driving forces negative succession policy orientation positive succession time series

Measurement-device-independent quantum communication without encryption

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Science Bulletin 2018年第20期63卷 1345-1350页

作者： Peng-Hao Niu Zeng-Rong zhou Zai-sheng lin Yu-Bo sheng Liu-Guo Yin Gui-Lu Long state Key Laboratory of Low-dimensional Quantum Physics Beijing 100084.China Department of Physics Tsinghua UniversityBeijing 100084China Collaborative Innovation Center of Quantum Matter Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China Beijing National Research Center for Information Science and Technology BeUing 100084China School of Information and Technology.Tsinghua University Beijing 100084China lnstiute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China College of Telecommunications &Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and TelecommunicationsMinistry of EducationNanjing 210003China

Security in communication is vital in modern life. At present, security is realized by an encryption process in cryptography. It is unbelievable if a secure communication is achievable without encryption. In quantum cryptography, there is a unique form of quantum communication, quantum secure direct communication, where secret information is transmitted directly over a quantum channel. Quantum secure direct communication is drastically distinct from our conventional concept of secure communication, because it does not require key distribution, key storage and ciphertext transmission, and eliminates the encryption procedure completely. Hence it avoids in principle all the security loopholes associated with key and ciphertext in traditional secure communications. For practical implementation, defects always exist in real devices and it may downgrade the security. Among the various device imperfections, those with the measurement devices are the most prominent and serious ones. Here we report a measurementdevice-independent quantum secure direct communication protocol using Einstein-Podolsky-Rosen pairs. This protocol eradicates the security vulnerabilities associated with the measurement device,and greatly enhances the practical security of quantum secure direct communication. In addition to the security advantage, this protocol has an extended communication distance, and a high communication capacity.

关键词： Quantum secure direct communication Measurement-device-independent Quantum dialogue Encryption Cryptography

Dimensionality Reducing from Three-dimensional RbLu5Te8 to Two-dimensional CsMnGdTe3:Syntheses,Crystal and Electronic Structures

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Chinese Journal of Structural Chemistry 2020年第10期39卷 1770-1780,1741页

作者： ZHANG Jian-Han zhou sheng-Hua lin Hua School of Resources&Chemical Engineering Sanming UniversitySanming 365004China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Two new rare-earth metal chalcogenides,namely RbLu5Te8 and CsMnGdTe3,have been successfully synthesized under high-temperature solid-state reaction conditions and structurally characterized by single-crystal X-ray diffraction ***5Te8 belongs to the monoclinic space group C2/m(no.12)with two formula units in a unit cell:a=22.075(5),b=4.2987(8),c=10.588(2)A,β=103.89(2)°,V=975.4(4)A3,whereas CsMnGdTe3 crystallizes in the orthorhombic space group Cmcm(no.63)with four formula units in a unit cell:a=4.4872(8),b=16.769(3),c=11.807(2)A and V=888.4(3)*** the structure of RbLu5Te8,face-,edgeand vertex-sharing[LuTe6]octahedra are interconnected to produce a three-dimensional(3D)framework with Rb^+lying in the *** crystal structure of CsMnGdTe3 consists of two-dimensional(2D)[MnGdTe3]^–layers of edge-and vertex-sharing[GdTe6]octahedra with Mn atoms filling the tetrahedral interstices,which stack along the *** Cs atoms are located between the[MnGdTe3]^–layers and surrounded by eight Te atoms to form a[CsTe8]bicapped trigonal ***,theoretical studies have aided the understanding of their electronic structures.

关键词： rare-earth telluride structural dimension high-temperature solid-state reaction crystal structure electronic structures

Spectral Response of Different Eroded Soils in Subtropical China: A Case Study in Changting County, China

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Journal of Mountain Science 2014年第3期11卷 697-707页

作者： lin Chen zhou sheng-lu WU Shao-hua ZHU Qing DANG Qi State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Department of Land Resources and Tourism Sciences School of Geographic and Oceanographic Sciences Nanjing University State Key Laboratory of Soil and Sustainable Agriculture Nanjing Insti-tute of Soil Science Chinese Academy of Sciences

Hyper-spectral data is widely used to determine soil properties. However, few studies have explored the soil spectral characteristics as response to soil erosion. This study analysed the spectral response of different eroded soils in subtropical China, and then identify the spectral characteristics and soil properties that better discriminate softs with different erosion degrees. Two methods were compared： direct identification by inherent spectral characteristics and indirect identification by predictions of critical soft properties. Results showed that the spectral curves for different degrees of erosion were similar in morphology, while overall reflectance and characteristics of specific absorption peaks were different. When the first method is applied, some differences among different eroded groups were found by integration of associated indicators. However, the index of such indicators showed apparent mixing and crossover among different groups, which reduced the accuracy of identification. For the second method, the correlation between critical soil properties, such as soil organic matter （SOM）, iron and aluminium oxides and reflectance spectra, was analysed. The correlation coefficients for the moderate eroded group were primarily between -0.3 to -0.5, which were worse than the other twogroups. However, the maximum value of R2 was obtained as 0.86 and 0.94 for the non-apparent eroded and the severe group. Furthermore, these two groups also showed some differences in the spectral response of iron complex state （Fep）, Aluminium amorphous state （Alo） and the modelling results for soil organic matter （SOM）. The study proved that it is feasible to identify different degrees of soil erosion by hyperspectral data, and that indirect identification by modelling critical soil properties and reflectance spectra is much better than direct identification. These results indicate that hyper-spectral data may represent a promising tool in monitoring and modelling soil erosio

关键词： Soil erosion Erosion degree Hyper-spectral Aluminium oxides Iron oxide SOM