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Amperometric Sensors for Determination of Hydrogen Peroxide Based on Electron Transfer Between Horseradish Peroxidase and 1，1＇－Dimethylferrocene

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Chemical Research in Chinese Universities 1995年第4期11卷 284-290页

作者： SUN Chang-qing luan chai-xia YANG Xu GAO Qian and XU Hong-ding(Department of Chemistry,Jilin University, Changchu,130023)DU Wen-yuan(The National Lab.of Enzyme Engineering,Jilin University, Chanchun, Chanchun,130023) JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA JILIN UNIV NATL LAB ENZYME ENGNCHANGCHUN 130023PEOPLES R CHINA

hydrogen peroxide electrode with 1,1'-dimethylferrocene(DMFc)used as an electron transfer mediator has been *** Nafion, DMFc was modified on a glassy carbon electrode(GCE)surface,and horseradish peroxidase(HRP)was then immobiliged on the DMFc-Nafion film,forming a HRp-DMFc-Nafion modi- fied electrode. The chracteristics of the sensor has been shown by cyclic voltam- metry and constant potential measurements,The sensor responds fastly to hydro- gen peroxide,the time required to reach 95%of the steady-state current is less than 50s. The sensor displays a sensitive catalytic current response to hydrogen peroxide and can be operated at a potential range in which the oxidation of common interfering species,such as ascorbic acid and uric acid,does not occur. The sensor is stable for 20 days and its detection limit is 1 μmol/L.

关键词： Dimethylferrocene,Nafion,Sensors,Amperometry Hydrogen peroxide

Advances and applications in single-cell and spatial genomics

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Science China Life Sciences 2025年

作者： Jingjing Wang Fang Ye Haoxi chai Yujia Jiang Teng Wang xia Ran Qimin xia Ziye Xu Yuting Fu Guodong Zhang Hanyu Wu Guoji Guo Hongshan Guo Yijun Ruan Yongcheng Wang Dong Xing Xun Xu Zemin Zhang Beijing Advanced Innovation Center for Genomics (ICG) Peking University Guangdong Provincial Key Laboratory of Genome Read and Write BGI Research Bone Marrow Transplantation Center of the First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Life Sciences Institute and The Second Affiliated Hospital Zhejiang University BGI Research Biomedical Pioneering Innovation Center (BIOPIC) and School of Life Sciences Peking University Academy for Advanced Interdisciplinary Studies Peking University Institute of Hematology Zhejiang University Department of Laboratory Medicine of The First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Center for Stem Cell and Regenerative Medicine Zhejiang University School of Medicine Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine Dr.Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine

The applications of single-cell and spatial technologies in recent times have revolutionized the present understanding of cellular states and the cellular heterogeneity inherent in complex biological systems. These advancements offer unprecedented resolution in the examination of the functional genomics of individual cells and their spatial context within tissues. In this review, we have comprehensively discussed the historical development and recent progress in the field of single-cell and spatial genomics. We have reviewed the breakthroughs in single-cell multi-omics technologies, spatial genomics methods, and the computational strategies employed toward the analyses of singlecell atlas data. Furthermore, we have highlighted the advances made in constructing cellular atlases and their clinical applications,particularly in the context of disease. Finally, we have discussed the emerging trends, challenges, and opportunities in this rapidly evolving field.

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Bullous pemphigoid associated with acquired hemophilia A: A case report

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World Journal of Clinical Cases 2025年第4期13卷 28-33页

作者： Su-Ye Hu Meng-Can Li Zi-Jia Hao Xu-Ya chai Pei-Sai Li Yang Liu Li-xia Liu Ying Xu Pan-Pan Yang Ling-E Li Department of Dermatology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina Graduate School Hebei University of Traditional Chinese MedicineShijiazhuang 050051Hebei ProvinceChina Department of Pathology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Acquired hemophilia A (AHA) is a rare and potentially severe bleeding disordercaused by circulating autoantibodies against factor Ⅷ (FⅧ). In approximately50% of the patients, the condition is associated with autoimmune diseases,cancers, medication use, pregnancy, and the post-partum period. Bullous pemphigoid(BP) is a chronic autoimmune subepidermal blistering disease associatedwith tissue-bound and circulating autoantibodies against BP antigens 180 (BP180)and 230 (BP230). AHA-associated BP has a high mortality rate;hence, the understandingof this disease must *** SUMMARY A 69-year-old man presented with erythema, blisters, blood blisters, and crustsaccompanied by severe pruritus for more than 20 days, and ecchymosis andswelling on his left upper arm for 3 days. Pathological examination revealed asubepidermal blister that contained eosinophils. Laboratory tests showed that theBP180 autoantibody levels had increased, isolated activated partial thromboplastintime was notably prolonged (115.6 s), and coagulation FⅧ activity wasextremely low (< 1.0%). Furthermore, the FⅧ inhibitor titer had greatlyincreased (59.2 Bethesda units). Therefore, the patient was diagnosed as having BP associated with AHA, prescribed 0.05% topical halometasone cream, and transferred to a higher-level hospitalfor effective treatment;however, he died after 2 *** AHA associated BP is rare, dangerous, and has a high mortality rate. Therefore, its timely diagnosis and effectivetreatment are necessary.

关键词： Bullous pemphigoid Acquired hemophilia A Acquired hemophilia A FactorⅧ Case report

Electron backscatter diffraction investigation of duplex-phase microstructure in a forged Zr-2.5Nb alloy

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Science China(Technological Sciences) 2016年第4期59卷 673-679页

作者： chai LinJiang WANG ShuYan luan BaiFeng LIU Qing College of Materials Science and Engineering Chongqing University College of Materials Science and Engineering Chongqing University of Technology

Microstructural features of a duplex-phase Zr-2.5Nb alloy were investigated in detail using electron channeling contrast （ECC） imaging and electron backscatter diffraction （EBSD） technique in an emission gun scanning electron microscope （FEGSEM）. The excellent resolution provided by the FEGSEM promises the combined utilization of both techniques to be quite adequate for characterizing the duplex-phase microstructures. Results show that the microstructure of the Zr-2.5Nb alloy is composed of bulk a grains （majority） in equiaxed or plate shape and thin 13 films （minority） surrounding the bulk grains, with their average grain size and thickness measured to be 1.4 prn and 72 nm, respectively. Analyses on a-grain boundaries reveal a number of low angle boundaries, most of which belong to deformation-induced dislocation boundaries. Measurements on relative propor- tions of various Burgers boundaries suggest very weak （if any） variant selection during 13 ~ a cooling, which should be re- lated to deformation-induced higher nucleation rate of a phases. Compared to earlier attempts, more satisfactory indexing of fine β phases （down to nanoscale） is attained by the FEGSEM-based EBSD. Examples are presented to clearly reveal well-obeyed Burgers orientation relationships between adjacent α and β phases. Finally, it is deduced that continuing applica- tion of the FEGSEM-based EBSD to duplex-phase Zr alloys could help clarify controversies like the deformation priority of the two phases.

关键词： Zr alloy duplex-phase microstructure electron backscatter diffraction

INFLUENCE OF SURFACTANT ON TWO-PHASE FLOW REGIME AND PRESSURE DROP IN UPWARD INCLINED PIPES

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Journal of Hydrodynamics 2012年第1期24卷 39-49页

作者： xia Guo-dong chai Lei Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of EducationCollege ofEnvironmental and Encrgy EngineeringBeijing University of TechnologyBeijing 100124China

The influence of a surfactant on the two-phase flow regime and the pressure drop in upward inclined pipes is investigated for various gas/liquid flow *** air/water and air/100 ppm sodium dodecyl sulphate aqueous solution are used as the working *** influence of the surfactant on the two-phase flow regime in upward inclined pipes is investigated using the electrical tomographic *** 0o,2.5o and 5o pipe inclinations,the surfactant has obvious effect on the transition from the stratified wavy flow to the annular flow,and the range of the stratified smooth flow regime is also extended to higher gas *** 10o pipe inclination,no stratified flow regime is observed in the air/water *** the air/surfactant solution system,however,the stratified flow regime can be found in the range of *** all inclination angles,the changes of the pressure gradient characteristics are accompanied with the flow pattern *** surfactant in a two-phase flow would reduce the pressure gradient significantly in the slug flow and annular flow *** the annular flow regime,the pressure gradient gradually becomes free of the influence of the upward inclined angle,and is only dependent on the property of the two-phase flow.

关键词： surfactant flow regime pressure drop two-phase flow

Periodic Solutions of Nonautonomous Second Order Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2005年第4期21卷 685-690页

作者： Shi xia luan An Min MAO Department of Mathematics Qufu Normal University Qufu 273165. P. R. China Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences. Beijing 100080. P. R. China

In this paper, we develop the local linking theorem given by Li and Willein by replacing the Palais-Smale condition with a Cerami one, and apply it to the study of the existence of periodic solutions of the nonautonomous second order Hamiltonian systems （H） ü＋A（t）u＋∨V（t, u）=0, u∈R^N, t∈R. We handle the case of superquadratic nonlinearities which differ from those used previously. Our results extend the theorems given by Li and Willem.

关键词： Non-autonomous Hamiltonian systems Periodic solutions Local linking Critical point theory Variational method

High-fidelity trajectory optimization for aeroassisted vehicles using variable order pseudospectral method

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Chinese Journal of Aeronautics 2021年第1期34卷 237-251页

作者： Runqi chai Antonios TSOURDOS AI SAVVARIS Senchun chai Yuanqing xia School of Aerospace Transport and ManufacturingCranfield UniversityBedfordshire MK43OALUnited Kingdom School of Automation Beijing Institute of TechnologyBeijing 100081China

In this study,the problem of time-optimal reconnaissance trajectory design for the aeroassisted vehicle is *** from most works reported previously,we explore the feasibility of applying a high-order aeroassisted vehicle dynamic model to plan the optimal flight trajectory such that the gap between the simulated model and the real system can be narrowed.A highly-constrained optimal control model containing six-degree-of-freedom vehicle dynamics is *** solve the formulated high-order trajectory planning model,a pipelined optimization strategy is *** approach is based on the variable order Radau pseudospectral method,indicating that the mesh grid used for discretizing the continuous system experiences several adaption *** of such a strategy can potentially smooth the flight trajectory and improve the algorithm convergence *** simulations are reported to demonstrate some key features of the optimized flight trajectory.A number of comparative studies are also provided to verify the effectiveness of the applied method as well as the high-order trajectory planning model.

关键词： Aeroassisted vehicle High-order Radau pseudospectral method Six-degree-of-freedom Trajectory design Variable order

Delineation of an Urban Community Life Circle Based on a Machine-Learning Estimation of Spatiotemporal Behavioral Demand

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Chinese Geographical Science 2021年第1期31卷 27-40页

作者： LI Chunjiang xia Wanqu chai Yanwei College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the life circles. This method, however, is constrained by GPS data, and it can only be applied in the GPS surveyed communities. To address this limitation, this study developed a generalizable delineation method without the constraint of behavioral data. According to previous research, the community life circle consists of the walking-accessible range and internal structure. The core task to develop the generalizable method was to estimate the spatiotemporal behavioral demand for each plot of land to acquire the internal structure of the life circle, as the range can be delineated primarily based on environmental data. Therefore, behavioral demand estimation models were established through logistic regression and machine learning techniques, including decision trees and ensemble learning. The model with the lowest error rate was chosen as the final estimation model for each type of land. Finally, we used a community without GPS data as an example to demonstrate the effectiveness of the estimation models and delineation method. This article extends the existing literature by introducing spatiotemporal behavioral demand estimation models, which learn the relationships between environmental contexts, population composition and the existing delineated results based on GPS data to delineate the internal structure of the community life circle without employing behavioral data. Furthermore, the proposed method and delineation results also contributes to facilities adjustments and location selections in life circle planning, people-oriented transformation in urban planning, and activity space estimation of the population in evaluating and improving the urban policies.

关键词： community life circle spatiotemporal behavioral demand demand estimation model decision tree ensemble learning

Catalytic Characteristics of Lipase Immobilized in CTAB/TX-100 MBG

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Chemical Research in Chinese Universities 2010年第1期26卷 110-113页

作者： SONG Shao-fang luan Yu-xia College of Chemistry and Material Science Shandong Agricultural University Tai ＇an 271018 P. R. China Institute of Pharmaceuties School of Pharmaceutical Science Shandong University Jinan 250100 P. R. China

CTAB/TX-100 microemtdsion-based gel（MBG）, which could be soaked in aqueous solution for a long time without mechanical strength and shape changes, was successfully prepared. Lipase immobilized in this gel had a higher activity than that in CTAB MBG when catalyzed the esterification reaction between n-hexanoic acid and n-octanol and its enantioselectivity was slightly higher when catalyzed the stereoselective esterification reaction between racemic ibuprofen and n-octanol. In aqueous solution, lipase in CTAB/TX-100 MBG could catalyze smoothly the hydrolysis reaction of olive oil and could be reused many times without the evident change of MBG mechanical strength although its activity decreased 41.8% after nine-time recycles.

关键词： Microemulsion-based gel(MBG) Immobilized lipase Activity Stereoselectivity Esterification Hydrolysis