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Chinese Journal of Polymer Science 2014年第2期32卷 187-196页

作者： hong-ying zhao 赵京波 Hao Li Tong zhao Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Laboratory of Advanced Polymer Materials Institute of Chemistry Chinese Academy Science

Two polyborosiloxanes （PBSis） with char yield up to 74.13% at 800 ℃ were synthesized by the direct polycondensation of boric acid with phenyltrimethoxysilane in diglyme. The PBSis were characterized by gel permeation chromatography, IR spectroscopy as well as ^1H-, ^29Si- and ^11B-NMR. PBSi modified phenol-formaldehyde resins （PBSi/PFs） were prepared at different PBSi/PF mass ratios and were cured at 150 ℃. The PBSi/PFs were characterized by IR spectroscopy, scanning electron microscopy, thermogravimetric analysis and tensile test. The results revealed that the cured PBSi/PFs had sea-island morphology and higher char yield than the common PF. PBSi/PF blend with PBSi/PF mass ratio of 0.4：1 had char yield up to 70.83% at 800 ℃. The PBSi/PFs had tensile strength similar to PF. The ceramization of PBSi/PFs was also studied. The silicon boron oxycarbide （SiBOC） ceramics formed were characterized by IR spectroscopy and elemental analysis. This method provided a valuable way to prepare easily shapeable polymer blends as ceramic precursors.

关键词： Polyborosiloxane Phenolic resin Preparation Ceramic precursors SiBOC ceramics.

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： Xing-Yuan Miao hong zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Well-dispersed Sb particles embedded on N-doped carbon nanofibers toward high-performance Li-ion battery

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Rare Metals 2024年第7期43卷 2994-3006页

作者： ying Li Yi-Han zhao Lu-Lu zhao Peng-Fei Wang ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern University Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at Qinhuangdao Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang University

The alloy-type material Sb is widely used in the anode materials of lithium-ion batteries（LIBs） due to its high theoretical specific ***,its serious volume expansion problem during alloying/dealloying of Li+limits its practical *** this work,C-Sb composite was constructed as anode material of LIBs by electrospinning route for the first time,Sb was introduced into the polyacrylonitrile-based hard carbon and coal tar pitch-based soft carbon composite amorphous carbon fiber with a diameter of 300-600 nm,which realized high cycling *** C-Sb-2（the mass ratio of polyacrylonitrile to Sb source is 1:2） electrode displayed charge capacities of 1098.5,930.3,841.7,753.5,643.9 and 545.8 mAh·g-1at 0.1,0.2,0.3,0.5,1 and 2 A·g-1,*** when the current density returned to 0.1 A·g-1,the charge capacity was 939.3 mAh·g-1,revealing good stability and *** introduction of Sb into the amorphous carbon improved its conductivity and addressed the volume expansion issue of high specific capacity Sb during charge/***-situ XRD analysis confirmed the high reversibility of the C-Sb-2 during charging and *** functional theory（DFT） calculations revealed the gradual enhancement of the interface interaction between SbxLiyand amorphous carbon（AMC） with increasing lithium content,contributing to the anchoring of alloy nanoparticles on the AMC surface and buffering the volume change of the ***,the gradual lithiation of Sb facilitated the electron transfer from SbxLiyto *** findings hold promise for designing lithium storage materials with exceptional performance,highlighting the potential of C-Sb composites as anode materials for efficient next-generation lithium storage.

关键词： Li-ion battery Metallic Sb Carbon Electrospinning Cycling stability

Stability analysis and stabilization of semi-Markov jump linear systems with unavailable sojourn-time information

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Science China(Information Sciences) 2024年第7期67卷 211-223页

作者： Xiaotai WU Yang TANG Shuai MAO ying zhao School of Mathematics and Physics Anhui Polytechnic University Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of EducationEast China University of Science and Technology

This study addresses the stability and stabilization problems of discrete-time semi-Markov jump linear systems(S-MJLSs) with unavailable sojourn-time information. The sojourn-time probability mass functions(S-TPMFs) of discrete-time semi-Markov chains are no longer confined to the geometric distribution, and it is difficult to obtain accurate and comprehensive information for S-TPMFs in practice. This is because S-TPMFs are usually deduced from the statistical characteristics according to the sampled-data, while adequate samples are often costly and time consuming. In this study, when the S-TPMFs for semi-Markov chains are assumed to be unavailable, the σ-error mean square stability is investigated for discrete-time S-MJLSs with some widely used assumptions; for semi-Markov chains, only the transition probability matrix of the embedded chain is used. In addition, the existence conditions of the effective controller are provided for closed-loop systems without using the information of S-TPMFs. Numerical examples are presented to illustrate the validity of the obtained theoretical results.

关键词： semi-Markov chain semi-Markov jump linear systems $\sigma$-error mean square stability unavailable sojourn-time information

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Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG ying LI Xin zhao Yanlong ZHANG Ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

Current understanding of ELF4 deficiency:a novel inborn error of immunity

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World Journal of Pediatrics 2024年第5期20卷 444-450页

作者： hong-Qiang Du Xiao-Dong zhao Department of Rheumatology&Immunology National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of Child Rare Diseases in Infection and ImmunityChildren’s Hospital of Chongqing Medical UniversityZhongshan Er Road 136Yuzhong DistrictChongqingChina

Background ELF4 deficiency has been recently recognized as a novel disorder within the spectrum of inborn errors of immunity(IEIs),specifically categorized as a“disease of immune dysregulation.”Cases of this condition,reported by our team and others,are very limited *** such,our current knowledge of this new disease remains *** review aims to provide a brief overview of the clinical manifestations,pathogenesis,and treatment strategies for this novel *** sources A comprehensive review was conducted after an extensive literature search in the PubMed/Medline database and websites concerning transcriptional factor ELF4 and reports concerning patients with ELF4 *** search strategy was“ELF4 OR ETS-related transcription factor Elf-4 OR EL4-like factor 4 OR myeloid Elf-1-like factor”as of the time of manuscript *** The current signature manifestations of ELF4 deficiency disorder are recurrent and prolonged oral ulcer,abdominal pain,and diarrhea in pediatric *** some cases,immunodeficiency and autoimmunity can also be *** Sanger sequencing or whole exome sequencing can be used to detect variation in ELF4 *** blotting for ELF4 expression of the patient’s cells can confirm the pathogenic effect of the *** fully confirm the pathogenicity of the variant,further functional test is strongly *** and biologics are the mainstream management of ELF4 deficiency *** Pediatric males presenting with recurring ulcerations in digestive tract epithelium with or without recurrent fever should be suspected of *** atypical presentations are prominent,variations in ELF4 gene should be carefully evaluated functionally due to the complex nature of ELF4 *** of treating DEX includes use of glucocorticoid and biologics and more precise treatment needs more patients to identify and further mechanistic study.

关键词： ELF4 transcription factor Immune dysregulation Inborn errors of immunity Mechanism Recurrent infections

Meromorphic Functions Sharing Two Values

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Wuhan University Journal of Natural Sciences 2024年第1期29卷 7-12页

作者： zhao ying HUANG Zhigang School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009JiangsuChina

Let f and g be two nonconstant meromorphic functions,and n be a positive *** f^(n)(z)and g^(n)(z)share 1 CM(counting multiplicities),f(z)and g(z)share∞IM(ignoring multiplicities),and N(r,1f)+N(r,1g)=S(r,f)+S(r,g),then either f(z)≡tg(z)or f(z)g(z)≡t,where t^(n)=*** an application,shared values problems of a meromorphic function related to its shifts and difference operators are also investigated.

关键词： meromorphic function shared values difference operator shift

Prevalence of hypertension and its associations with body composition across Chinese and American children and adolescents

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World Journal of Pediatrics 2024年第4期20卷 392-403页

作者： Li-Wang Gao Yi-Wen Huang hong Cheng Xi Wang hong-Bo Dong Pei Xiao Yin-Kun Yan Xin-ying Shan Xiao-Yuan zhao Jie Mi Center for Non-Communicable Disease Management Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthNo.56 Nanlishi RoadXicheng DistrictBeijing100045China Department of Epidemiology Capital Institute of PediatricsNo.2 Yabao RoadChaoyang DistrictBeijing100020China Key Laboratory of Major Diseases in Children Ministry of EducationBeijingChina

Background The age of onset of hypertension(HTN)is decreasing,and obesity is a significant risk *** prevalence and racial disparities in pediatric HTN and the association between body composition and blood pressure are insufficiently *** study aimed to evaluate the prevalence of HTN in Chinese and American children and adolescents and to assess the relationship between various body composition indices and *** Seven thousand,five hundred and seventy-three Chinese and 6239 American children and adolescents aged 8–18 years from the 2013–2015 China Child and Adolescent Cardiovascular Health study and the 2011–2018 National Health and Nutrition Examination Surveys were *** pressure and body composition(fat and muscle)were measured by trained *** crude prevalence and age-standardized prevalence rate(ASPR)of primary HTN and its subtypes[isolated systolic hypertension(ISH)and isolated diastolic hypertension(IDH)]were calculated based on 2017 American Academy of Pediatrics ***-adjusted linear regression coefficients and odds ratios(ORs)were calculated to assess the associations of body composition indicators with HTN,ISH and *** The ASPR of HTN was 18.5%in China(CN)and 4.6%in the United States(US),whereas the obesity prevalence was 7.4%and 18.6%,and the population attributable risk of HTN caused by overweight and obesity was higher in the US than in *** fat mass,muscle mass and body fat percentage mass were associated with a higher risk of HTN in both *** percent of muscle body mass had a protective effect on HTN and ISH in both countries[HTN(CN:OR=0.83,95%CI=0.78–0.88;US:OR=0.72,95%CI=0.64–0.81);ISH(CN:OR=0.87,95%CI=0.80–0.94;US:OR=0.71,95%CI=0.62–0.81)],and the protective effect was more common among children and adolescents with high levels of physical *** The burden of HTN in Chinese children and adolescents was substantial and much greater than that in the US,and th

关键词： Body composition Children and adolescents China Child and Adolescent Cardiovascular Health Hypertension National Health and Nutrition Examination Surveys

A study on carbon emission calculation in operation stage of residential buildings based on micro electricity usage behavior:Three case studies in China

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Building Simulation 2024年第1期17卷 147-164页

作者： Menghan Niu ying Ji Miao zhao Jiefan Gu Aonan Li Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing 100124China College of Architecture and Urban Planning Tongji UniversityShanghai 201804China The Bartlett School of Architecture University College LondonWC1E 6BTUK

Along with the improvement of social productivity and living standard,residential buildings generate a growing portion of carbon emissions,especially during the operation ***,energy use behaviors are usually ignored in carbon emission *** study focuses on calculating carbon emissions during the operation stage for residential buildings based on the characteristics of energy use behaviors in different ***,we investigated energy use behaviors in dwellings across three cities in China:Xi'an,Shanghai and ***,we established calibrated carbon emission models and optimization models with different green building measures for residential *** results of this research reveal a significant disparity between the energy usage habits of residents in different climate *** carbon emissions of residential electricity bills in Xi'an,Shanghai and Fuzhou are 13.6 kgCO_(2)/(m^(2)·a)(excluding central heating),29.3 kgCO_(2)/(m^(2)·a)and 17.2 kgCO_(2)/(m^(2)·a),*** carbon emissions account for 32.2%-64.1% of the *** comparison to the model based on internal standard setting,the accuracy of the models using actual internal has improved by 25.9%-37.4%.The three-star green building methods have the highest carbon reduction rate among different star buildings,the emission reduction rates are around 30%.This study's findings are useful for carbon emission calculation and green building design of residential buildings in the future.

关键词： residential building energy usage behavior energy simulation carbon emissions

Anti-epileptic and Neuroprotective Effects of Ultra-low Dose NADPH Oxidase Inhibitor Dextromethorphan on Kainic Acid-induced Chronic Temporal Lobe Epilepsy in Rats

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Neuroscience Bulletin 2024年第5期40卷 577-593页

作者： Jing-Jing Yang ying-Xin Liu Yan-Fang Wang Bi-ying Ge ying Wang Qing-Shan Wang Sheng Li Jian-Jie Zhang Ling-Ling Jin Jau-Shyong hong Sheng-Ming Yin Jie zhao College of Basic Medical Sciences Dalian Medical UniversityDalian116044China Department of Neurology The First Affiliated Hospital of Dalian Medical UniversityDalian116011China National and Local Joint Engineering Research Center for Drug Research and Development of Neurodegenerative Diseases Dalian116044China School of Public Health Dalian Medical UniversityDalian116044China Neurobiology Laboratory National Institute of Environmental Health SciencesNational Institutes of HealthResearch Triangle ParkDurhamNC27709USA

Neuroinflammation mediated by microglia and oxidative stress play pivotal roles in the development of chronic temporal lobe epilepsy(TLE).We postulated that kainic acid(KA)-Induced status epilepticus triggers microglia-dependent inflammation,leading to neuronal damage,a lowered seizure threshold,and the emergence of spontaneous recurrent seizures(SRS).Extensive evidence from our laboratory suggests that dextromethorphan(DM),even in ultra-low doses,has anti-inflammatory and neuroprotective effects in many animal models of neurodegenerative *** results showed that administration of DM(10 ng/kg per day;subcutaneously via osmotic minipump for 4 weeks)significantly mitigated the residual effects of KA,including the frequency of SRS and seizure *** addition,DM-treated rats showed improved cognitive function and reduced hippocampal neuronal *** found suppressed microglial activation-mediated neuroinflammation and decreased expression of hippocampal gp91^(phox) and p47^(phox) proteins in KA-induced chronic TLE ***,even after discontinuation of DM treatment,ultra-low doses of DM continued to confer long-term anti-seizure and neuroprotective effects,which were attributed to the inhibition of microglial NADPH oxidase 2 as revealed by mechanistic studies.

关键词： Temporal lobe epilepsy Dextromethorphan NADPH oxidase Ultra-low dose