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Thermoelectric Transport Properties of R_yFe_3NiSb_(12)(R=Ba,Nd and Yb)

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Journal of Materials science & technology 2014年第11期30卷 1134-1140页

作者： Ruiheng liu Jung Young Cho jiong yang Wenqing Zhang lidong Chen CAS Key Laboratory for Energy-conversion Materials Shanghai Institute of CeramicsChinese Academy of Sciences Materials and Processes Laboratory GM R&D CenterWarrenMI 48090USA Department of Materials science & Engineering University of Washington

To evaluate the influence of Ni substitution on electrical transport properties, the thermoelectric transport properties of the p-type skutterudites RyFe3NiSb12 （R = Ba, Nd and Yb） are systematically investigated from 2.5 K to 800 K. By carefully modifying the filling fractions of the three fillers, Ba, Nd and Yb, the carrier concentration is precisely adjusted, which changes proportionally to the nominal value calculated by valence counting rule. The carrier concentration dependences of mobility and Seebeck coefficient represent two band contribution in the valence band, and the optimized carrier concentration for thermoelectric performance is between （5-9） × 10^20 cm^-3. The lattice thermal conductivity of samples filled with rare-earth elements （Nd and Yb） are significantly lower as compared to Ba-filled, due to the lower resonant frequency and partial filling. Compared with Co substitution, Ni substitution tends to close the band gap, which results in heavier bipolar diffusion at high temperature for RyFe3NiSb12. However, due to state, when the carrier concentrations are similar, RyFe3NiSb12 possess higher thermal power and thus higher power factor than RyFe2Co2Sb12 in the lower temperature range. A ZT value of 0.73 is obtained for Yb0.77Fe3NiSb12 at 660 K.

关键词： Thermoelectric Skutterudites Band structure Bipolar diffusion

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活性位点附近氨基酸对解淀粉芽孢杆菌核糖核酸酶Barnase酶学性质的影响

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安徽大学学报（自然科学版） 2024年第5期48卷 71-81页

作者：李鹏龙王雷李兴江吴学凤洪泂穆冬冬合肥工业大学食品与生物工程学院安徽合肥230601 中国科学技术大学附属第一医院(安徽省立医院)医保处安徽合肥230001 中国科学技术大学生命科学学院安徽合肥230026

Barnase活性位点附近氨基酸与底物之间的相互作用会影响酶与底物的识别从而影响酶的催化,为了研究活性位点附近氨基酸如何影响催化从而获得更高活性和稳定性的Barnase,采用定点突变技术对解淀粉芽孢杆菌BH072核糖核酸酶Barnase活性位点... 详细信息

Barnase活性位点附近氨基酸与底物之间的相互作用会影响酶与底物的识别从而影响酶的催化,为了研究活性位点附近氨基酸如何影响催化从而获得更高活性和稳定性的Barnase,采用定点突变技术对解淀粉芽孢杆菌BH072核糖核酸酶Barnase活性位点附近氨基酸进行突变,将突变体酶分别诱导表达、纯化并表征,检测其比酶活和热稳定性.得到最高比酶活的突变酶为N131A,比酶活为41.65 kU·mg^(-1),相较野生型提高了43.82%.该突变体在60℃放置12 h后仍能保持80%的酶活力.为了探究活性位点附近残基突变对催化反应造成影响的原因,笔者使用同源建模及分子对接分析了催化口袋与底物的相互作用,发现N131A突变提高了酶分子结合底物的能力.该研究所获得的突变体N131A进一步丰富了核糖核酸酶突变体酶库,具有良好应用前景.

关键词：核糖核酸酶定点突变稳定性催化活性

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Photochemically induced thalamus infarction impairs cognition in a mouse model

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Stroke & Vascular Neurology 2023年第6期8卷 444-452,I0001,I0002页

作者： Chen Zhang Shiping li Yongjun Wang jiong Shi Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina china National Clinical Research Center for Neurological Diseases BeijingChina Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina

Background Small subcortical infarcts account for up to 25%of ischaemic *** is one of the subcortical structures that commonly manifest with lacunar infarcts on MRI of the *** have shown that thalamus infarction is associated with cognitive ***,due to the lack of proper animal models,little is known about the *** aimed to establish a focal thalamus infarction model,characterise the infarct lesion and assess functional *** Male C57BL/6J mice were anaesthetised,and Rose Bengal dye was injected through the tail *** right thalamus was illuminated with green laser light by stereotactic implantation of optic *** of the infarct and lesion evolution were evaluated by histological analysis and 7T MRI at various *** cognitive and neurological functions were assessed by behavioural *** tracing was performed to analyse neural *** An ischaemic lesion with small vessel occlusion was observed in the *** became a small circumscribed infarct with reactive astrocytes accumulated in the infarct periphery on day *** mice with thalamic infarction demonstrated impaired learning and memory without significant neurological *** labelled neurons in the retrosplenial granular cortex were *** This study established a mouse model of thalamic lacunar infarction that exhibits cognitive *** connection dysfunctions may play a potential role in post-stroke cognitive *** model helps to clarify the pathophysiology of post-stroke cognitive impairment and to develop potential therapies.

关键词： infarction thalamus impaired

Study on Near Distributed Dynamic Model of a Multifountain-and-multiconfluent Network System of Steam Main-pipeline and Parallel Coursing Units

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Study on Near Distributed Dynamic Model of a Multifountain-a...

Research on Self-regulation of Delay Arming Time of MR Fluid Fuze

The 5th International Symposium on Measurement Techniques for Multiphase Flows(5th ISMTMF)

作者： Pan Lei Shen jiong School of Energy and Environment Southeast university Nanjing china

＜正＞According to the deficiency of the prior modeling methods on main-pipeline system,the paper advances a near distributed modeling way based on subsection,combination and delamination for parallel coursing units and main-pipehne system to fully show its distributed dynamics by an easy-simulated mode of ***,a principle is established to plot out the main-pipeline into some short pipe-sections between each pair of fountain/confluent points. Secondly,a near distributed decouphng transfer function matrix model without steady error for each pipe-section is built by rationally approximate deduction and then joined with the dynamic models of the fountain/confluent at the two ends of the pipe-section to form the near distributed model of each ***,a smooth arithmetic is adopted to joint all the conterminous subsections into a whole system *** modeling method above decreases the dimension of matter space and integrates more influence factors on the systern dynamic characteristics into the built model,such as pipe length,diameter and the thermodynamics of working fluid,so it more particularly reflects the distributed dynamic characteristics of a multifountain-and-multiconfluent network system of steam main-pipeline and parallel coursing units than before,and can act well as the simulated research object for advanced main-pipeline system control arithmetic and distributed control technology or even validates *** simulation experiments have been done and produced good results to prove the validity of the modeling method.

关键词： parallel coursing unit dynamic mathematic model distributed parameter decoupling control multifountain-and-multiconfluent networks

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Research on Self-regulation of Delay Arming Time of MR Fluid...

Hybrid integration method for highly maneuvering radar target detection based on a Markov motion model

2010 Chinese Control and Decision Conference

作者： Hongsheng Hu~(1,2),jiong Wang~2,Bo liu~2 1.School of Mechanical and Electrical Engineering,Jiaxing university,Jiaxing,314001,china 2.School of Mechanical Engineering,Nanjing university of science and technology,Nanjing,210094,china

＜正＞With the development of science and technology,its performance of delay arming device has been continually ***,bore premature,premature detonation,failure to fire and other grave accidents have still often happened in recent *** reason is that delay arming device prematurely rescinds fuse safety mechanism or its fail of delaying arming *** has been widely focused on how to improve its safety and reliability of delay arming device at home and abroad,but there have only been few researches on its self-regulation of delay arming *** on its principle of MR fluid damp controlling technology and its yield stress of MR fluid will be changed with its changes of magnetic field strength,design and simulation of magnetic circuit for MR fluid fuze has been done in this *** this model among input current of coil,discharge aperture and time of discharge has been obtained by test and some useful results are made by numerical *** experimental results prove that its delay arming time of MR fuze meets the design requirements and indicate that input current of coil has an obvious effect on discharge time.

关键词： Delay arming time Magnetorheological fluid fuze Self-regulation Magnetic field

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Chinese Journal of Aeronautics 2020年第6期33卷 1717-1730页

作者： Yingxiao ZHAO Zengping CHEN Yue ZHANG Jie CHEN jiong yang Yunsheng XIONG National Key L aboratory of science and technology on ATR National University of Defense TechnologyChangsha 410073China School of Electronic and Communication Engineering Sun Yat-sen UniversityShenzhen 518107China

To detect highly maneuvering radar targets in low signal-to-noise ratio conditions, a hybrid long-time integration method is proposed, which combines Radon-Fourier Transform(RFT), Dynamic Programming(DP), and Binary Integration(BI), named RFT-DP-BI. A Markov model with unified range-velocity quantification is formulated to describe the maneuvering target’s motion. Based on this model, long-time hybrid integration is performed. Firstly, the whole integration time is divided into multiple time segments and coherent integration is performed in each segment via RFT. Secondly, non-coherent integration is performed in all segments via DP. Thirdly, 2/4 binary integration is performed to further improve the detection performance. Finally, the detection results are exported together with target range and velocity trajectories. The proposed method can perform the long-time integration of highly maneuvering targets with arbitrary forms of ***, it has a low computational cost that is linear to the integration time. Both simulated and real radar data demonstrate that it offers good detection and estimation performances.

关键词： Binary integration Dynamic programming Long-time integration Maneuvering targets Markov motion model Radar target detection Radon-Fourier transform

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Prognostic Nomogram for Patients with Hepatitis E Virus-related Acute liver Failure:A Multicenter Study in china

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Journal of Clinical and Translational Hepatology 2021年第6期9卷 828-837页

作者： Jian Wu Cuifen Shi Xinyu sheng Yanping Xu Jinrong Zhang Xinguo Zhao jiong Yu Xinhui Shi Gongqi li Hongcui Cao Lanjuan li State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infec-tious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiangChina Depart-ment of Laboratory Medicine Shanghai Tongji HospitalTongji University School of MedicineShanghaiChina Department of Infectious Disease The Second People’s Hospital of Yancheng CityYanchengJiangsuChina Department of Laboratory Medicine The People’s Hospital of Dafeng CityYanchengJiangsuChina Department of Respiration The Fifth People’s Hospital of WuxiWuxiJiangsuChina Department of Laboratory Medicine The First People’s Hospital of Yancheng CityYanchengJiangsuChina Department of Clinical Laboratory Linyi Traditional HospitalLinyiShandongChina Zhejiang Provincial Key Laboratory for Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases HangzhouZhejiangChina

Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently *** present study aimed to establish an effective nomogram for predicting the mortality of HEV-ALF ***:The nomogram was based on a cross-sectional set of 404 HEV-ALF patients who were identified and enrolled from a cohort of 650 patients with liver *** compare the performance with that of the model for end-stage liver disease(MELD)scoring and CliF-Consortiumacute-on-chronic liver failure score(CliF-C-ACLFs)models,we assessed the predictive accuracy of the nomogram using the concordance index(C-index),and its discriminative ability using time-dependent receiver operating characteristics(td-ROC)analysis,***:Multivariate logistic regression analysis of the development set carried out to predict mortality revealed that γ-glutamyl transpeptidase,albumin,total bilirubin,urea nitrogen,creatinine,international normalized ratio,and neutrophil-to-lymphocyte ratio were independent factors,all of which were incorporated into the new nomogram to predict the mortality of HEV-ALF *** area under the curve of this nomogram for mortality prediction was 0.671(95%confidence interval:0.602-0.740),which was higher than that of the MELD and CliF-C-ACLFs ***,the td-ROC and decision curves analysis showed that both discriminative ability and threshold probabilities of the nomogram were superior to those of the MELD and CliF-C-ACLFs models.A similar trend was observed in the validation ***:The novel nomogram is an accurate and efficient mortality prediction method for HEV-ALF patients.

关键词： Hepatitis E Acute liver failure Nomogram Mortality prediction Scoring model

Hydrogen sulfide promotes angiogenesis in vitro and in vivo

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Hydrogen sulfide promotes angiogenesis in vitro and in vivo

Novel 3D local feature descriptor of point clouds based on spatial voxel homogenization for feature matching

中国生理学会第23届全国会员代表大会暨生理学学术大会

作者： Ming-Jie WANG~1,Wen-Jie CAI~2,Dan-Dan HAO~1,Na li~1,Ying CHEN~1,Ying-jiong DING~1,Yi-Chun ZHU~1 1 Department of Physiology and Pathophysiology,Fudan university Shanghai Medical College.Shanghai 200032,china 2 Department of Basic medicine,university of Shanghai for science and technology,Shanghai 200093,china

Introduction:Hydrogen sulfide(HS),a novel gasotransmitter,has been shown to play an important role in regulating cardiovascular functions,including maintaining basal systolic blood pressure,inhibiting neointimal hyperplasia,exerting negative inotropic effect and inhibiting ischemia-reperfusion *** date,there is little information about the potential role of HS in ***:Cultured RF/6A endothelial cells,C57 mouse Matrigel plug model and rat hind limb ischemia model were *** vitro angiogenesis study includes endothelial cell proliferation,migration and tube formation assay,and ERK,Akt and p38 signaling *** measurement and morphological analysis were performed with ex vivo Matrigel plug *** vivo angiogenesis study includes microangioraphy,fluorescent microsphere assay,capillary density quantification and VEGF-VEGFR2 expression ***:10μmol/L NaHS(HS donor) promoted RF/6A endothelial cell proliferation,migration and tube *** angiogenic response is largely dependent on activation of PI3K/Akt.10 and 50μmol/kg/d NaHS also promoted ex vivo angiogenesis in C57 mouse Matrigel plug model.50μmol/kg/d NaHS significantly increased collateral vessel formation,capillary density and blood supply to the ischemic hind *** upregulation of VEGF expression in ischemic skeletal muscles and VEGFR2 phosphorylation in neighboring vascular ECs suggest a role for VEGF in mediating the effects of NaHS on interactions between myocytes and endothelial cells. Conclusions:Exogenous HS is a pro-angiogenic factor both in vitro and in *** may therefore be used as a supplement to ischemic diseases.

关键词： hydrogen sulfide angiogenesis endothelial cells hind limb ischemia

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Visual Computing for Industry,Biomedicine,and Art 2023年第1期6卷 257-278页

作者： jiong yang Jian Zhang Zhengyang Cai Dongyang Fang School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhouHenan 450001China School of Management Hefei University of TechnologyHefeiAnhui 230009China

Obtaining a 3D feature description with high descriptiveness and robustness under complicated nuisances is a significant and challenging task in 3D feature *** paper proposes a novel feature description consisting of a stable local reference frame(LRF)and a feature descriptor based on local spatial ***,an improved LRF was designed by incorporating distance weights into Z-and X-axis ***,based on the LRF and voxel segmentation,a feature descriptor based on voxel homogenization was ***,uniform segmentation of cube voxels was performed,considering the eigenvalues of each voxel and its neighboring voxels,thereby enhancing the stability of the *** performance of the descriptor was strictly tested and evaluated on three public datasets,which exhibited high descriptiveness,robustness,and superior performance compared with other current ***,the descriptor was applied to a 3D registration trial,and the results demonstrated the reliability of our approach.

关键词： Local feature descriptor Voxel Local reference frame Feature extraction