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Chinese Journal of Polymer Science 2024年第6期42卷 751-765页

作者： Jun-hao Zhou Li-Ming Tang Key Laboratory of Advanced Materials of Ministry of Education of China Department of Chemical EngineeringTsinghua UniversityBeijing100084China

In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot *** prepolymers were characterized fully by various ***,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and *** from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical ***,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their *** influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then *** composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT *** addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.

关键词： Polyurethane-urea methacrylate Hindered urea bond ZnO nanoparticles Reprocessing UV curing

Accurate Distinction of Weak and Strong AC Grids for Emerging Hierarchical-Infeed LCC-UHVDC Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 772-777页

作者： hao Xiao Xianzhong Duan Yi Zhang department of Electrical and Computer Engineering University of ManitobaWinnipeg R3T 2N2ManitobaCanada State Key Laboratory of Advanced Electromagnetic Engineering and Technology Hubei Electric Power Security and High Efficiency Key LaboratorySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina RTDS Technologies Inc. Winnipeg R3T 2E1ManitobaCanada

Distinction of weak and strong AC grids for emerging hierarchical-infeed LCC-UHVDC systems is important for planning and operation departments. However, accuracy of earlier distinction methods is limited as they were developed by empirical reasoning without rigorous theoretical analysis. Hence in this letter, hierarchical-infeed interactive effective short-circuit ratio (HIESCR) index is first used for strength evaluation of HIDC systems with complex inter-inverter interactions considered. Boundary HIESCR (BHIESCR) is also introduced in the proposed distinction method of weak and strong AC grids. That is, weak (or strong) AC grids are, respectively, identified when HIESCR is less (or greater) than BHIESCR. Second, it is shown BHIESCR remains almost unchanged as 3.0 versus various system parameters and rated operation variables based on rigorous theoretical analysis. This salient feature makes the proposed method more accurate than earlier methods. Finally, the proposed method is validated by simulations based on the PSCAD/EMTDC program.

关键词： Hierarchical-Infeedinteractive effective short-circuit ratio hierarchical-infeed LCC-UHVDC systems inter-inverter interactions strong AC grids weak AC grids

原发性血小板增多症患者中JAK2、CALR及三阴性驱动突变的临床特征比较

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中国实验血液学杂志 2024年第1期32卷 197-201页

作者：李雨蒙杨二鹏王子卿王德好牛继聪李芋锦明静孙明谦陈卓刘为易吕妍胡晓梅中国中医科学院研究生院北京100700 中国中医科学院西苑医院血液科北京100091 中国中医科学院西苑医院基础医学研究所北京100091

目的:探讨原发性血小板增多症(ET)患者的突变基因与临床特征的关系。方法:对2018年10月至2022年3月69例ET患者的临床资料进行回顾性分析。将患者按突变的驱动基因类型分为JAK2组、CALR组与三阴性组,对3组患者的性别、年龄、心血管危险... 详细信息

目的:探讨原发性血小板增多症(ET)患者的突变基因与临床特征的关系。方法:对2018年10月至2022年3月69例ET患者的临床资料进行回顾性分析。将患者按突变的驱动基因类型分为JAK2组、CALR组与三阴性组,对3组患者的性别、年龄、心血管危险因素、血栓、脾肿大、血常规、凝血状态进行分析。结果:69例ET患者中,46例伴随JAK2基因突变,14例伴随CALR基因突变,8例为三阴性,1例伴随MPL基因突变。3组患者的年龄、性别无显著差异(P>0.05)。JAK2组血栓率最高,为26.09%(12/46),三阴性组为12.5%(1/8),CALR组无血栓事件。JAK2组伴随脾肿大发生率最高,为34.78%(16/46),而三阴性组无脾肿大发生。JAK2组的白细胞数为(9.00±4.86)×10^(9)/L,显著高于CALR组的(6.03±2.32)×10^(9)/L(P<0.05)。JAK2组的血红蛋白含量为(148.43±18.79)g/L,显著高于三阴性组的(131.00±15.17)g/L(P<0.05)。JAK2组的红细胞压积为(0.44±0.06)%,亦显著高于三阴性组的(0.39±0.05)%(P<0.05)。JAK2组血小板数为(584.17±175.77)×10^(9)/L,显著低于CALR组的(703.07±225.60)×10^(9)/L(P<0.05)。JAK2组和三阴性组纤维蛋白原含量分别为(2.64±0.69)g/L和(3.05±0.77)g/L,均显著高于CALR组的(2.24±0.47)g/L(P<0.05,P<0.01)。三阴性组活化部分凝血活酶时间为(28.61±1.99)s,较CALR组的(31.45±3.35)s显著降低(P<0.05)。结论:不同驱动基因突变ET患者的血细胞计数与凝血状态存在差异。与CALR组相比,JAK2组血栓率、白细胞数和纤维蛋白原含量均显著升高,而血小板数显著降低;与三阴性组相比,JAK2组脾大发生率和红细胞压积显著升高;与CALR组相比,三阴性组的纤维蛋白原含量显著升高、活化部分凝血活酶时间显著降低。

关键词：原发性血小板增多症二代基因测序驱动突变凝血

Multi-Robot Cooperative Localization: Time-Varying Unobservable Subspace Analysis and Consistent Algorithm design

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Journal of Systems Science & Complexity 2024年第5期37卷 1937-1955页

作者： hao Ning HE Fenghua YAO Yu School of Astronautics Harbin Institute of Technology

This paper investigates the problem of cooperative localization(CL) for a multi-robot system(MRS) under dynamic measurement topology, which involves a group of robots collectively estimating their poses with respect to a common reference frame using ego-motion measurements and robot-to-robot relative measurements. The authors provide a theoretical analysis of the time-varying unobservable subspace and propose a consistent cooperative localization algorithm. First, the authors introduce the relative measurement graph(RMG) to represent the relative pose measurements obtained by the MRS at each instant. Then, the authors derive the local observability matrix over a time *** equivalent relationship is established between the local observability matrix and the spectral matrices of the RMG. Moreover, the authors present a method for constructing the unobservable subspace based on the RMG under different topology conditions. Based on this analysis, the authors design a consistent cooperative localization algorithm that satisfies the constraints of the time-varying unobservable subspace. An analytical optimal solution is derived for the constrained optimization *** Carlo numerical simulations are conducted to demonstrate the consistency and accuracy of the proposed method.

关键词： Consistency cooperative localization multi-robot system null space relative measurement graph time-varying unobservable subspace

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： hao Lin Cheng He School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

A novel distributed solar refrigeration system based on evacuated U-tube solar collector and elastocaloric refrigerator

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Science China(Technological Sciences) 2024年第9期67卷 2797-2810页

作者： LI hao ZHANG HouCheng College of New Energy Ningbo University of TechnologyNingbo 315211China

Refrigeration challenges in regions with electricity shortages significantly decrease the quality of life for residents. In response to the prevalent refrigeration challenges in power-deficient areas, a novel distributed solar refrigeration system, comprising an evacuated U-tube solar collector and elastocaloric refrigerator, is theoretically introduced. Theoretical formulations for the energy efficiency and cooling power of the solar refrigeration system are presented to facilitate predictive assessments of the performance properties. Under typical conditions, the energy efficiency and cooling power of the solar refrigeration system are,respectively, 4.84% and 200.15 W. Subsequently, an extensive parameter study is conducted to comprehensively uncover key performance influencers and identify avenues for improvement. In addition, local sensitivity analyses identify that the length ratio is the top influential parameter, while the heat transfer fluid flow rate is the least sensitivity. A pragmatic case study,conducted with the weather data of Ningbo City, China, serves to empirically predict the performance of the hybrid system within the constraints of practical circumstances.

关键词： evacuated U-tube solar collector elastocaloric refrigerator solar refrigeration solar energy thermal utilization system integration

delayed diagnosis in inflammatory bowel disease:Time to consider solutions

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World Journal of Gastroenterology 2024年第35期30卷 3954-3958页

作者： hao Lv hao-Yu Li hao-Nan Zhang Yang Liu department of General Surgery Xi'an Jiaotong University Second Affiliated HospitalXi'an 710004Shaanxi ProvinceChina

In this editorial,we discuss a recently published manuscript by Blüthner et al in the World Journal of Gastroenterology,with a specific focus on the delayed diagnosis of inflammatory bowel disease(IBD).IBD,which includes Crohn's disease and ulcerative colitis,is a chronic intestinal disorder.A time lag may exist between the onset of inflammation and the appearance of signs and symptoms,potentially leading to an incorrect or delayed diagnosis,a situation referred to as the delayed diagnosis of *** diagnosis is crucial for effective patient treatment and prognosis,yet delayed diagnosis remains *** reasons for delayed diagnosis of IBD are numerous and not yet fully *** key factor is the nonspecific nature of IBD symptoms,which can easily be mistaken for other ***,the lack of specific diagnostic methods for IBD contributes to these *** diagnosis of IBD can result in numerous adverse consequences,including increased intestinal damage,fibrosis,a higher risk of colorectal cancer,and a decrease in the quality of life of the ***,it is essential to diagnose IBD promptly by raising physician awareness,enhancing patient education,and developing new diagnostic methods.

关键词： Inflammatory bowel disease delayed diagnosis Diagnostic methods Early diagnosis Consequences of inflammatory bowel disease

Fabrication of corrosion inhibiting microcapsules functional coating and their high-efficiency corrosion resistance

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Rare Metals 2024年第2期43卷 842-848页

作者： hao-Ran Yun Lu Lu Xue-Long hao Xing-Xiang Zhang School of Material Science and Engineering Tiangong UniversityTianjin300387China National Center of Analysis and Testing for Nonferrous Metals and Electronic Materials General Research Institute for Nonferrous MetalsBeijing100088China Guobiao(Beijing)Testing&Certification Co. Ltd.Beijing101407China

Benzotriazole(BTA)was loaded into calcium carbonate microsphere shell by self-assembly method and a new type of high-efficiency corrosion inhibiting microcapsules(CIMs)were fabricated,which were added and dispersed into epoxy resin coating to obtain a new corrosion resistance functional *** corrosion inhibition effect of benzotriazole on aluminum alloy matrix was verified by polarization curve *** effectiveness of the CIMs and their loading capacity on inhibitor were evaluated by scanning electron microscope,laser confocal Raman spectroscopy together with thermogravimetric analysis.

关键词： corrosion coating resistance

Structural engineering of hard carbon through spark plasma sintering for enhanced sodium-ion storage

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Rare Metals 2024年第9期43卷 4274-4285页

作者： hao-Ming Xiao Heng Zheng Ping Yuan Jun-Hui Luo Lin-Lin Shen Jie-Feng Tan Xian-You Luo de Li Yong Chen Guangdong Key Laboratory for Hydrogen Energy Technologies School of Materials Science and Hydrogen EnergyFoshan University State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti ResourcesHainan University

Hard carbon （HC） has emerged as one of the superior anode materials for sodium-ion batteries （SIBs）,with its electrochemical performance significantly influenced by the presence of oxygen functional groups and its closed pore ***,current research on the structural adjustment of these oxygen functional groups and the closed pore architecture within HC remains ***,energy-efficient and contamination-free spark plasma sintering technology was employed to tune the structure of coconut-shell HC,resulting in significant adjustments to the content of carboxyl （decreasing from 5.71 at%to 2.12 at%） and hydroxyl groups （decreasing from 7.73 at % to 6.26 at%）.Crucially,these modifications reduced the irreversible reaction of oxygen functional groups with Na+.Simultaneously,a substantial number of closed pores with an average diameter of 1.22 nm were generated within the HC,offering an ideal environment for efficient Na+*** structural changes resulted in a remarkable improvement in the electrochemical performance of the modified *** reversible specific capacity of the modified HC surged from 73.89 mAh·g-1to an impressive 251.97 m Ah·g-1at a current density of 50 mA·*** at 400 mA·g-1,the reversible specific capacity increased significantly from 14.55 to 85.44 mAh·***,this study provides a novel perspective for designing tailored HC materials with the potential to develop high-performance SIBs.

关键词： Closed pores Hard carbon Oxygen functional groups Sodium-ion batteries Spark plasma sintering

A level line of the Gaussian free field with measure-valued boundary conditions

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Science China Mathematics 2024年第2期67卷 367-404页

作者： Titus Lupu hao Wu Laboratoire de Probabilités Statistique et ModélisationSorbonne Universitéand UniversitéParis CitéCNRSParis F-75005France Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China

In this article, we construct samples of Schramm-Loewner-evolution-like curves out of samples ofthe conformal loop ensemble and Poisson point processes of Brownian excursions. We show that the laws of thesecurves depend continuously on the intensity measure of the Brownian excursions. Using such a construction ofcurves, we extend the notion of level lines of the Gaussian free field to the case where the boundary conditionis measure-valued.

关键词： Schramm-Loewner evolution conformal loop ensemble Brownian excursion Gaussian free field