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Journal of Arid Land 2018年第1期10卷 27-38页

作者： nan ling dong zhibao xiao weiqiang li chao xiao nan song shaopeng xiao fengjun du lingtong School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Research Center for Westerm Development Ningxia UniversityYinchuan 750021China Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China Ningxia UniversityYinchuan 750021China

The farming-pastoral ecotone in northern China is an extremely fr@e ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we conducted field simulated wind erosion experiments combined with laboratory analysis to investigate wind erosion of soils in trampled rangeland, non-tilled cropland and tilled cropland in Yanchi County, China. The results showed that compared with rangeland, the cropland had a higher soil water holding capacity and lower soil bulk density. The wind erosion rate of trampled rangeland was much higher than those of non-tilled cropland and tilled cropland. For cropland, the wind erosion rate of the soil after tilling was surprisingly less than that of the soil before tilling. With increasing of wind speed, the volume mean diameter of the eroded sediment collected by the trough in the wind tunnel generally increased while the clay and silt content decreased for all soils. The temporal variation in wind erosion of the trampled rangeland indicated that particle entrainment and dust emission decreased exponentially with erosion time through the successive wind erosion events due to the exhaustion of erodible particles.

关键词： wind erosion rate wind tunnel eroded sediment soil particle size cropland rangeland semi-arid region

The Hilbert expansion of the Boltzmann equation in the incompressible Euler level in a channel

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Science China Mathematics 2025年第1期68卷 39-88页

作者： Feimin Huang weiqiang Wang Yong Wang Feng xiao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and StatisticsHunan Normal University

The study of the hydrodynamic limit of the Boltzmann equation with physical boundary is a challenging problem due to the appearance of the viscous and Knudsen boundary *** this paper,the hydrodynamic limit from the Boltzmann equation with the specular reflection boundary condition to the incompressible Euler equations in a channel is *** on the multi-scaled Hilbert expansion,the equations with boundary conditions and compatibility conditions for interior solutions,and viscous and Knudsen boundary layers are derived under different scaling,***,some uniform estimates for the interior solutions,and viscous and Knudsen boundary layers are *** the help of the L2-L∞framework and the uniform estimates obtained above,the solutions to the Boltzmann equation are constructed by the truncated Hilbert expansion with multiscales,and hence the hydrodynamic limit in the incompressible Euler level is justified.

关键词： Boltzmann equation incompressible Euler equations hydrodynamic limit Hilbert expansion specular reflection boundary condition viscous boundary layer Knudsen boundary layer

Incorporating organic-modified nano SiO_(2) for the comprehensive improvement of recycled PET

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Chinese Journal of Structural Chemistry 2023年第4期42卷 10-12页

作者： Lina Song Nan Zhou Feng Gao Huawen Wang Haifeng Wang Chunyi Hu weiqiang xiao Dangguo Cheng Qinghua Zhang Quan Liu Institute of Zhejiang University-Quzhou Zhejiang Provincial Innovation Center of Advanced Chemicals TechnologyQuzhou324000China College of Chemical and Biological Engineering Zhejiang UniversityZhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyHangzhou310027China China Tobacco Zhejiang Industrial Co.Ltd HangzhouZhejiang310008China Zhejiang Zhongtian Dongfang Fluorosilicone Material Co. Ltd.Quzhou324004China

*** Polyethylene terephthalate(PET)is a thermoplastic resin with excellent optical transparency,gas barrier and mechanical properties,widely used in fibers,plastics and film[1-3].However,PET has a long degradation half-life in the natural environment,and greenhouse gases such as carbon dioxide will be produced after incineration,indicating that recycling is an effective way to reduce plastic pollution and save energy,and how to correctly use recycled PET(rPET)has become a global concern[4-7].It was reported that each 0.45 kg recycled PET sheet used can reduce energy consumption by 84%and greenhouse gas emissions by 71%compared with the original PET production[8,9].

关键词： plastics transparency resin

Risk Factors of Influenza-Associated Necrotizing Encephalopathy in Children

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Journal of Behavioral and Brain Science 2021年第8期11卷 193-203页

作者： Guangming Liu Sida Yang Suyun Li Qinglian Chen weiqiang xiao Peiqing Li Pediatric Emergency Department Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Pediatric Neurology Department Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Pediatric Radiology Department Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China

Objective: A case-control study of Influenza-Associated Necrotizing Encephalopathy (IANE) in children was conducted to explore the risk factors for the diagnosis of IANE, and to provide a predictive reference for the diagnosis of IANE. Methods: The children with IANE who received treatment in our hospital from January 2016 to December 2020 were selected as the study group, and the children with Influenza-Associated Encephalopathy (IAE) group who received treatment in the same period were selected as the control group. The blood biochemical, coagulation function and cerebrospinal fluid test results of the two groups were analyzed by univariate analysis. Receiver Operating Characteristic curve (ROC) analysis was used to determine the optimal threshold point of each index for the indicators with statistically significant differences in univariate analysis results, and multivariate Logistic stepwise regression analysis was performed according to the optimal threshold points. Results: In the IANE group, there were 32 children, including 20 males and 12 females, aged 60 (35, 84) months. There were 40 children in IAE group, including 26 males and 14 females, aged 58 (23, 97) months. Univariate results showed that serum Lactate Dehydrogenase (LDH), Cerebrospinal Fluid Lactate Dehydrogenase (CSF LDH) and Cerebrospinal Fluid Protein (CSF PRO) in the IANE group were significantly higher than those in the IAE group, and the difference between the two groups was statistically significant (P 535 U/L (OR = 31.264, 95% CI: 5.892 - 165.878, P 0.49 g/L (OR = 7.695, 95% CI: 1.052 - 56.305, P = 0.044) were independent risk factors for IANE. Conclusion: For children with influenza whose neurological symptoms appear rapi

关键词： Children Influenza-Associated Necrotizing Encephalopathy Risk Factor

Brain Complications with Influenza Infection in Children

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Journal of Behavioral and Brain Science 2020年第3期10卷 129-152页

作者： Qinglian Chen Peiqing Li Suyun Li weiqiang xiao Sida Yang Hui Lu Guangzhou Medical University Guangzhou China Department of Radiology Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Department of Pediatric Neurology Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Institute of Pediatrics Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China

Objectives: To summarize the characteristics and research progress of influenza-associated brain complications in children and provide references for early diagnosis and brain protection treatment. Methods: Studied published articles of influenza-associated neurocomplications in children from PubMed and summarizes them from epidemiology, clinical manifestations, diagnosis and treatment, and basic research progress. Results: Common brain complications in flu-children include febrile seizures, influenza-associated encephalopathy (IAE), acute or post-influenza encephalitis, and the most severe condition is acute necrotizing encephalopathy (ANE). However, the mechanism and relevant factors of influenza-associated brain damage have not been elucidated. Conclusion: Influenza could be accompanied by various brain lesion complications in dif ferent stages of the disease, some of which are life-threatening or leave severe neurological sequelae, such as ANE. Due to different brain injury mechanisms, specific early diagnosis and brain protection treatment for different complications are unclear or unanimous. Therefore, further classification and basic research are needed.

关键词： Brain Lesions Risk Factor Influenza Children

Central Brain Herniation Secondary to Influenza-Related Encephalopathy in a Pontocerebellar Hypoplasia Child: A Case Report and Review

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Journal of Behavioral and Brain Science 2020年第6期10卷 257-264页

作者： weiqiang xiao Peiqing Li Yuzhi Yao Sida Yang Suyun Li Shuyao Ning Hongsheng Liu Department of Pediatric Radiology Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Department of Pediatric Emergency Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Department of Surgery Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Department of Pediatric Neurology Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Department of Neuroelectrophysiology Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China

Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with influenza who had a pontocerebellar hypoplasia (PCH) history;she performed the second Magnetic Resonance Imaging (MRI) on Day 6 from onset, showed the diffuse edema and the occurrence of central herniation;the medulla was “Z-like” folded and the basal cisterns were obliterated completely. Finally she was declared dead. The imbalance between supratentorial and infratentorial pressure can lead to the occurrence of CBH. Severe edema relates to IAE and unstable structure of the posterior fossa might be the main reason for the herniation. MRI is helpful in early diagnosis. Early treatment of cerebral edema in patients with congenital abnormalities of the posterior fossa is vital for their management.

关键词： Pontocerebellar Hypoplasia Central Brain Herniation Influenza-Related Encephalopathy Magnetic Resonance Imaging

Characteristics and Mortality Risk Factors of Influenza-Associated Encephalopathy/Encephalitis in Children in a Tertiary Pediatric Hospital in China, 2016-2019

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Journal of Behavioral and Brain Science 2021年第7期11卷 157-170页

作者： Yongling Song Tianxiang Qiu weiqiang xiao Suyun Li Yan Hong Qiang Wang Qinglian Chen xiaowei Fan Peiqing Liu Department of Pediatric Emergency Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China Medical Imaging Department Guangzhou Women and Children’s Medical Center Guangzhou Medical University Guangzhou China

Background: Seasonal influenza associated neurological complications had high mortality and morbidity rates in children. In this study, we aimed to investigate the clinical characteristics and mortality risk factors in children with influenza-associated encephalopathy. Methods: Retrospectively analyze the clinical data, laboratory tests, and imaging examinations of 68 children diagnosed with influenza-associated encephalopathy from January 2016 to December 2019 at Guangzhou Women and Children’s Medical Center, and the cases were divided into survival and non-survival groups by disease outcome and analyzed between two groups. Chi-square test or Mann-Whitney rank sum test was used for comparison between groups, and multivariate Logistic regression analysis was used for the analysis of risk factors for death. Results: Among the 68 children with influenza-associated encephalopathy, 40 were male, and 28 were female, aged from 3 months to 13 years, of which 66.18% (45/68) were under 5 years old. Pathogenetic tests showed that influenza virus type A accounted for 63.24% (43/68), and influenza virus type B accounted for 36.76% (25/68). Typical brain MRI changes in childhood influenza-associated encephalopathy were bilateral symmetrical lesions of the thalamus, basal ganglia, brainstem, and cerebellum. 68 patients had a mortality rate of 20.59% (14/68), with a significantly higher proportion of fever peak > 39°C, Acute Disturbance of Consciousness (ADOC), and cardiac arrest in the non-survival group than in the survival group (P < 0.05). Laboratory tests showed significantly higher in Alanine Aminotransferase (ALT), Aspartate Transaminase (AST), Creatinine Kinase (CK), Lactate Dehydrogenase (LDH), lactate, and C-Reactive Protein (CRP). And CSF protein levels in the non-survival group compared with the survivor (P < 0.05), among them, elevated ALT, AST, LDH, and CSF protein were independent high-risk factors for death from influenza-associated encephalopa

关键词： Children Influenza Encephalopathy Encephalitis Clinical Characteristics Risk Factor

等离激元纳米晶玻璃的研究进展以及非线性光学应用

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硅酸盐学报 2024年第8期52卷 2517-2526页

作者：万子轩徐建肖卫强刘小峰浙江大学材料科学与工程学院杭州310027 浙江中烟工业有限责任公司杭州310024

玻璃作为应用最广的光学材料,其性质不仅取决于其本身的化学组成,还可以通过向其中引入不同性质的纳米晶进行调控。当玻璃中引入贵金属等离激元纳米晶后,由于局域表面等离激元共振(LSPR)效应,会使得玻璃出现鲜艳的颜色。本文综述了各种... 详细信息

玻璃作为应用最广的光学材料,其性质不仅取决于其本身的化学组成,还可以通过向其中引入不同性质的纳米晶进行调控。当玻璃中引入贵金属等离激元纳米晶后,由于局域表面等离激元共振(LSPR)效应,会使得玻璃出现鲜艳的颜色。本文综述了各种含有贵金属、非贵金属等离激元纳米晶玻璃的光学性质及其制备方法,还讨论了近年来等离激元纳米晶玻璃在非线性光学以及超快光子学领域的应用。最后简要总结了等离激元纳米晶复合玻璃的研究现状以及潜在的发展方向。

关键词：微晶玻璃等离激元非线性光学

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注册会计师执业准则体系的突出特点和作用

中国注册会计师 2006年第5期 27-28页

作者：萧伟强毕马威华振会计师事务所

财政部近日发布的48项中国注册会计师执业准则,在考虑中国特有的经济环境的基础上,充分借鉴了国际审计准则的规定,形成一套由鉴证业务准则、相关服务准则和质量控制准则共同构成的全面体系.

关键词：注册会计师执业准则突出特点准则体系国际审计准则质量控制准则经济环境鉴证业务财政部中国

城市轨道交通牵引供电接触轨系统温度应力有限元分析

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城市轨道交通研究 2017年第7期20卷 108-111页

作者：张桂林肖伟强郑州铁路职业技术学院郑州讲师451200 广州市地下铁道总公司广州510320

温度变化时接触轨内部会产生巨大的温度应力,严重时甚至会危及城市轨道交通牵引供电安全。结合目前应用较广泛的钢铝复合接触轨,基于有限单元法,采用三维软件SOLIDWORKS建模,并在有限元软件Ansys Workbench中对接触轨模型的温度应力进... 详细信息

温度变化时接触轨内部会产生巨大的温度应力,严重时甚至会危及城市轨道交通牵引供电安全。结合目前应用较广泛的钢铝复合接触轨,基于有限单元法,采用三维软件SOLIDWORKS建模,并在有限元软件Ansys Workbench中对接触轨模型的温度应力进行了模拟分析。该模型考虑了卡爪、尼龙垫块及支座等构件的束缚影响,采用边界条件控制环境的温度变化,得到了接触轨内部温度应力场云图,并分析了此温度应力对绝缘支座的影响。研究结果可为接触轨系统中各构件的设计、优化、安装及检修提供参考。

关键词：牵引供电接触轨系统温度应力有限元分析