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Influence of Vanadium Content on Bainitic Transformation of a Low-Carbon Boron Steel During Continuous Cooling

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 692-698页

作者： Kwang-Su Kim Lin-Xiu Du cai-Ru gao State Key Laboratory of Rolling and Automation Northeastern University Department of Materials Kim Chaek University of Technology

The phase transformation behaviors during continuous cooling of low-carbon boron steels with different vanadium contents were studied by means of dilatometric measurement and microstructure observation. The bainite transformation behavior is not noticeably altered when the vanadium content is 0.042 and 0.086 wt%, and these steels exhibit full bainitic microstructure even at a cooling rate of 5 ℃/s. When vanadium content is increased to 0.18 wt%, ferrite is still present in the microstructure even at a cooling rate of 40 ℃/s. Vickers hardness of the steels with 0.042 and 0.086 wt% V is remarkably higher than that of the steel with 0.18 wt% V at a cooling rate higher than 10 ℃/s, and the difference is increased with the increase in cooling rate. Moreover, the amount of coarse vanadium precipitates formed in austenite is increased with the increase in vanadium content. The optimum content of vanadium to obtain bainitic microstructure is 0.086 wt% in this experimental low-carbon boron steels.

关键词： Microalloyed steel Vanadium Bainitic transformation Boron Microstructure

β-Cyclodextrin and its derivatives-enhanced solubility and biodegradation of 2-nitrobiphenyl

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Journal of Environmental Sciences 2006年第6期18卷 1157-1160页

作者： cai Bang-cheng gao Shi-xiang LU Gen-fa State Key Laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing 210093 China

This paper investigated the effects of β-cyclodextrins （I3-CD） and its two derivatives, hydroxypropyl-β-cyclodextrin （HPCD） and carboxymethyl-β-cyclodextrin （CMCD）, on the solubility and biodegradation of 2-nitrophenyl by an A cinetbacter sp. Results showed that β-CD, HPCD and CMCD could not be utilized by A cinetbacter sp. as sole carbon source and none of the CDs had toxic effects on the growth of the bacteria in the experiments; all the CDs could enhance the apparent solubility and accelerate the biodegradation of 2-nitrobipheny. It showed that biodegradation-accelerating effects of CDs on 2-nitrobiphenyl were correlated with their solubility-enhancing effects. Among three CDs investigated, CMCD had the most obvious effects both on the apparent solubility and the biodegradation, followed by β-CD and HPCD.

关键词： β-CD HPCD CMCD 2-nitrophenyl biodegradation

Controlled preparation and application of glutathione capped gold and platinum alloy nanoclusters with high peroxidase-like activity

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Journal of Materials Science & Technology 2022年第14期109卷 140-146页

作者： Yan-cai gao Chong Wang Chun-Xia Zhang Hong-Wei Li Yuqing Wu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityNo.2699 Qianjin StreetChangchun 130012China Department of Hepatic-Biliary-Pancreatic Medicine First HospitalJilin UniversityNo.71 Xinmin StreetChangchun 130021China Institute of Theoretical Chemistry College of ChemistryJilin UniversityNo.2 Liutiao RoadChangchun 130023China

In the present study,we have prepared glutathione capped gold and platinum alloy nanoclusters(AuPtNCs)in a controlled way by employing the hydrothermal method and optimized through adjusting the ratio of raw materials,reaction temperature,and *** with the corresponding monometallic gold and platinum nanoclusters,the alloy nanoclusters’catalytic activity is improved dramatically in the oxidation of 3,3,5,5-tetramethylbenzidine(TMB)in the presence of H_(2)O_(2).And the maximum velocity is calculated to be 106×10^(-8)M·s^(-1) for TMB as substrate,being much better than that of other reported metallic nanoclusters and *** study shows that the high catalytic activity mainly attributes to the synergistic effect of gold and ***,they have been applied to determine H_(2)O_(2)in the presence of TMB,which shows high sensitivity with a limit of detection(LOD)at 100 n *** proposed method has been used to determine H_(2)O_(2)in milk and contact lens solutions,which shows very good recovery and exhibits high practical application ***,the present study provides a new type of alloy nanoclusters with high peroxidase-like activity,which will inspire more research interests on doping and alloying with Pt to improve the catalytic activity of metal nanoclusters.

关键词： Alloy nanoclusters Hydrothermal method Catalytic activity Synergistic effect Platinum

Calorimetric Studies on Enthalpy Relaxation in Maltitol Glass Transition Based on Phenomenological Models

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Chemical Research in Chinese Universities 2012年第6期28卷 1078-1085页

作者： YE Bin gao cai YANG Suo LIU Xiang-nong JIANG Bin School of Mechanical and Automotive Engineering Hefei University of Technology Hefei 230009 P. R. China

To investigate the enthalpy relaxation behavior of maltitol glass system,differential scanning calorimetry（DSC） was used to obtain the specific heat capacity[C p（T）] near the glass transition temperature（T g） at different cooling rates ranged between 1 and 20 K/*** phenomenological models of enthalpy relaxation,ToolNarayanaswamy-Moynihan（TNM） model,Adam-Gibbs-Vogel（AGV） model and Gómez Ribelles（GR） model,were used to simulate the experimental *** models＇ parameters were obtained via a curve-fitting *** results indicate that TNM and AGV models gave the almost identical prediction powers and can reproduce the curves of experimental C p（T） very ***,the prediction power of GR model evolved from configurational entropy approach is not so good as those of TNM and AGV *** particular,the metastable limit state parameter（δ） introduced by Gómez Ribelles has insignificant effect on the enthalpy relaxation of the small molecular hydrogen-bonding glass system.

关键词： Differential scanning calorimetry(DSC) Maltitol Glass transition Enthalpy relaxation Tool-Narayanaswamy-Moynihan(TNM) model Adam-Gibbs-Vogel(AGV) model Gómez Ribelles(GR) model Dynamic fragility

Design and Dynamic Model of a Frog-inspired Swimming Robot Powered by Pneumatic Muscles

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1123-1132页

作者： Ji-Zhuang Fan Wei Zhang Peng-Cheng Kong He-gao cai Gang-Feng Liu State Key Laboratory of Robotics and System Harbin Institute of Technology

Pneumatic muscles with similar characteristics to biological muscles have been widely used in robots, and thus are promising drivers for frog inspired robots. How- ever, the application and nonlinearity of the pneumatic system limit the advance. On the basis of the swimming mechanism of the frog, a frog-inspired robot based on pneumatic muscles is developed. To realize the indepen- dent tasks by the robot, a pneumatic system with internal chambers, micro air pump, and valves is implemented. The micro pump is used to maintain the pressure difference between the source and exhaust chambers. The pneumatic muscles are controlled by high-speed switch valves which can reduce the robot cost, volume, and mass. A dynamic model of the pneumatic system is established for the sim- ulation to estimate the system, including the chamber, muscle, and pneumatic circuit models. The robot design is verified by the robot swimming experiments and the dynamic model is verified through the experiments and simulations of the pneumatic system. The simulation results are compared to analyze the functions of the source pressure, internal volume of the muscle, and circuit flow rate which is proved the main factor that limits the response of muscle pressure. The proposed research provides the application of the pneumatic muscles in the frog inspired robot and the pneumatic model to study muscle controller.

关键词： Frog-inspired robot Pneumatic muscle High-speed switch valve Pneumatic model

Limit Analysis of Defect-Free Pipe Elbow Under Internal Pressure With Mean Yield Criterion

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Journal of Iron and Steel Research International 2013年第4期20卷 11-15页

作者： ZHANG Shun-hu gao cai-ru ZHAO De-wen WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University

With mean yield（MY）criterion,an analytical solution of the collapse load for a defect-free pipe elbow under internal pressure is first *** is a function of ratio of thickness to radius t0/r0,strain hardening exponent n,curvature influence factor mand ultimate tensile *** collapse load increases with the increase of m,and it is the same as the burst pressure of straight pipe if m=1is *** MY-based solution is compared with those based on Tresca,Mises and twin shear stress（TSS）yield criteria,and the comparison indicates that Tresca and twin shear stress yield criteria predict a lower bound and an upper bound to the collapse load ***,the MY-based solution lies just between the TSS and Tresca solutions,and almost has the same precision with the Mises solution.

关键词： limit analysis pipe elbow internal pressure strain hardening exponent MY criterion

Prevalence of Epstein-Barr virus infection and characteristics of lymphocyte subsets in newly onset juvenile dermatomyositis

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World Journal of Pediatrics 2021年第2期17卷 205-209页

作者： Qi Zheng Kun Zhu cai-Na gao Yi-Ping Xu Mei-Ping Lu Department of Rheumatology Immunology and AllergyChildren’s HospitalZhejiang University School of Medicine57#Zhu Gan RoadHangzhou 310000China Department of Pathology Children's HospitalZhejiang University School of MedicineHangzhouChina

Background The underlying etiology of juvenile dermatomyositis(JDM)is unknown.T cell deficiency as well as Epstein-Barr virus(EBV)infection had been suspected to be involved in the pathogenesis,but it has been poorly evaluated in JDM *** This study described the traits of T and B lymphocyte subsets in newly onset JDM patients and the incidence of EBV infection in JDM patients compared with match *** developed JDM patients from 2014 to 2018 were included in the *** with different markers(CD3+,CD3+CD4+,CD3+CD8+,CD3-CD19+and CD3-CD16+CD56+)were tested with flow cytometry in the first admission or after 6 months of *** analysis was conducted to compare the EBV infection in the group of JDM patients and *** We observed that JDM patients had higher positive rate of Epstein-Barr nuclear antigen-immunoglobulin G(IgG)(P<0.0001)as well as EBV capsid antigen-IgG(P<0.05)than normal ***3-CD16+CD56+lymphocyte was found to be extremely low in early stage of JDM patients,but increased after 6 months of treatment(P=0.0091).Conclusions The level of CD3-CD16+CD56+cells may associate with the clinical course of *** may act as an environmental factor predisposing patients to the development of JDM.

关键词： Epstein-barr virus Juvenile dermatomyositis Lymphocytes

Anomalous retinal artery associated with branch retinal artery occlusion and neovascular glaucoma: A case report

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World Journal of Clinical Cases 2020年第5期8卷 980-985页

作者： Wan-Ju Yang Yan-Ning Yang Ming-gao cai Yi-Qiao Xing Eye Center Renmin Hospital ofWuhan UniversityWuhan 430060Hubei ProvinceChina Department of Ophthalmology The Central Hospital of WuhanTongji MedicalCollege of Huazhong University of Science and TechnologyWuhan 430014Hubei ProvinceChina

BACKGROUND Congenital anomalous retinal artery is rare and does not typically affect visual ***,an abnormal artery that passes through and supplies blood to the macular area complicated with branch retinal artery occlusion may negatively impact visual *** study reports an unusual case of anomalous retinal artery combined with retinal artery *** SUMMARY A 52-year-old male presented with severely reduced vision in the right *** fundus examination revealed an anomalous artery,extending from the superior temporal arcade and crossing the macula into the inferior temporal *** anomalous artery was partially occluded,with a narrowed lumen.A cherry-red spot was observed with whitening of the macular area,suggesting macular *** fluorescein angiography revealed disc leakage and a delayed filling *** coherence tomography revealed increased thickness of the neuroretina and underlying *** patient was treated with vessel dilation,hyperbaric oxygen,ocular massage,and *** acuity of the right eye subsequently improved to 20/200 from hand motion at 4 *** improvement in visual acuity persisted when the patient was examined at the 1-mo follow-up *** patient was subsequently followed via telephone *** information provided via interview indicated that visual acuity in the affected eye was stable up to 6 years from the time of the initial ***,after 3 additional years,the patient was diagnosed with neovascular glaucoma in the right eye,which was subsequently *** Although congenital retinal vascular anomaly,including anomalous retinal artery,rarely affects vision,when complicated with branch retinal artery occlusion,the abnormal artery that supplies the macula may severely reduce visual acuity.

关键词： Branch retinal artery occlusion Vascular abnormality Case report

Microstructure,compression property and shape memory effect of Ru-Nb high temperature shape memory alloy

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Rare Metals 2007年第S1期26卷 51-55页

作者： gao Xin,cai Wei,and gao Zhiyong School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The microstructure,phase transformation,compression property and strain recovery characteristics of equiatomic Ru-Nb high temperature shape memory alloy were investigated by means of optical microscope,X-ray diffraction(XRD),differential scanning calorimetry(DSC),compression tests and transmission electron microscopy(TEM).When cooling the alloy specimen from high temperature to room temperature,β(parent phase)→β’(interphase)→β″(martensite) two step phase transformation *** microstructure at room temperature shows regularly arranged band morphology with the monoclinic crystal *** twinning relationship between the martensite bands was determined to be(101) Type *** and of the martensite bands inside the variant and dislocation were found during compression at room *** maximum complete recovery strain is about 1.5%.

关键词： Ru-Nb alloy phase transformation microstructure shape memory effect