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Synthesis and Properties of SEPS-g-PEO Copolymers with Varying Branch Lengths

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Chinese Journal of Polymer Science 2018年第8期36卷 934-942页

作者： Zhong-Fu zhao Pei-Ying Liu Chun-Qing Zhang Wei Liu Yan-hui Wang Tao Tang Yi-Fu Ding Yan-Dong Zhang Fan-Zhi Meng State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of Technology State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Department of Mechanical Engineering University of Colorado Boulder

Poly（ethylene oxide）（PEO） was controllably grafted from styrene-b-（ethylene-co-propylene）-b-styrene （SEPS） backbones by combining lithiation of styrenic units and living monomer-activated anionic ring-opening polymerization of ethylene oxide （EO） monomers with the aid of co-initiators triisobutyl aluminum. The as-synthesized SEPS-g-PEO copolymers were characterized by SEC, 1H-NMR, FTIR, SAXS, AFM and DSC. When the branch length is relatively small, increase of PEO fraction leads to the increase of the correlation length between neighboring hard domains, but the degree of correlation reduces. When the branch length is relatively large, the phase-separated structures become random both in terms of size and spatial correlation, and macro-phase separated structures appear. The crystallization behavior of the PEO branches can be effectively inhibited in SEPS-g-PEO, so no significant crystallization takes place until the fraction of PEO branches is 20.1 wt%, which greatly promotes the rapid delivery of hydrophilic drugs in the hot-melting pressure- sensitive adhesives （HMPSAs） based on SEPS-g-PEO. Their cumulative release amount of a model drug could achieve 80%, more than twice the value in the HMPSAs based on linear PEO-containing styrenic block copolymers.

关键词： Living anionic polymerization SEPS-g-PEO copolymers Phase structures Drug delivery

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三江源区鱼类多样性调查及保护对策

水生态学杂志 2024年第5期45卷 1-8页

作者：陈锋袁婷熊满堂赵先富马沛明朱滨张志永刘晖董方勇李键庸水利部中国科学院水工程生态研究所水利部水工程生态效应与生态修复重点实验室湖北武汉430079

了解三江源区鱼类多样性及其资源现状,为三江源区生态系统保护和流域管理提供科学依据。2022年8月开展了长江源、黄河源、澜沧江源鱼类调查,分析了3.水系鱼类组成与分布,探讨了鱼类多样性特征,研究了三江源地区鱼类群落的空间格局。结... 详细信息

了解三江源区鱼类多样性及其资源现状,为三江源区生态系统保护和流域管理提供科学依据。2022年8月开展了长江源、黄河源、澜沧江源鱼类调查,分析了3.水系鱼类组成与分布,探讨了鱼类多样性特征,研究了三江源地区鱼类群落的空间格局。结果表明:三江源区共调查到鱼类18种,其中长江源9种,黄河源8种,澜沧江源6种;根据相对重要性指数,长江源优势种3.,依次为细尾高原鳅(Triplophysa stenura)、小头高原鱼(Herzensteinin microcephalus)、裸腹叶须鱼(Ptychobarbus dipogon),黄河源优势种2种,包括麻尔柯高原鳅(***)和黄河裸裂尻鱼(Schizopygopsis pylzovi),澜沧江源优势种4种,依次为前腹裸裂尻鱼(***)、裸腹叶须鱼、东方高原鳅(***)和细尾高原鳅;三江源区鱼类多样性相对较低,其中澜沧江源最高,长江源次之,黄河源最低。对鱼类种类组成进行聚类分析,结果表明长江源和澜沧江源相近,黄河源则与长江源、澜沧江源差距较大。为切实保护好三江源区鱼类资源,建议加强本底调查,开展关键栖息地生态环境监测和保护,构建三江源区水生生物资源数据库,关注气候变化对水生态环境的影响,预防和控制外来鱼类入侵。

关键词：鱼类多样性空间格局优势种保护对策三江源区

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Significance of Diffusion Tensor Imaging of Vastus Medialis Oblique in Recurrent Patellar Dislocation

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Chinese Medical Journal 2017年第6期130卷 642-646页

作者： Li-Si Liu Zhuo-zhao Zheng hui-Shu Yuan Department of Radiology Peking University Third Hospital Beijing 100191 China Department of Radiology Tsinghua Changgung Hospital Beijing 102218 China

Background： Numerous studies have investigated the influence of osseous factors on patellofemoral joint instability, but research on the influence of dynamic muscle factors in vivo is still in the exploratory stage. This study aimed to use magnetic resonance imaging （MRI） and diffusion tensor imaging （DTI） to evaluate vastus medialis oblique （VMO） fiber bundles in patients with recurrent patellar dislocation to explore the changes in muscle morphology and function. Methods： This prospective study involved 3. patients （7 males and 23.females; average age, 21.4 ± 3.8 years） clinically diagnosed with recurrent patellar dislocation in Peking University Third Hospital and 3. healthy volunteers matched for age, sex, and body mass index in our medical school between January 2014 and October 2014. None of the patients had a recent history of traumatic patellar dislocation or transient patellar dislocation. All patients underwent conventional MRI and DTI of the knee. The cross-sectional area of the VMO on MRI and the fractional anisotropy （FA）, apparent diffusion coefficient （ADC）, and primary （λ1）, secondary （λ2）, and three-level characteristic （λ3. values on DTI were measured. The independent-samples t-test was used to compare these parameters between the two groups. Results： Compared with the control group, the patient group showed significantly higher FA values （0.3. ± 0.05 vs. 0.3. ± 0.03. and significantly lower ADC （1.51 ± 0.13.vs. 1.58± 0.07）, λ2 （4.96 ±0.13.vs. 5.04 ± 0.07）, and λ3.values （4.44 ± 0.14 vs. 4.58 ± 0.07; t = 5.99, t = -2.58, t = 3.02, and t = -4.88, respectively： all P 〈 0.05）. Cross-sectional VMO area and λ1 values did not differ between the two groups （t = 1.82 and t = 0.22, respectively; both P 〉 0.05）. Conclusions： The functional status of the VMO is closely associated with recurrent patellar dislocation. MRI, especially DTI （FA, ADC, λ2, and ,λ3., can detect early changes in VMO function and might lhcilitate the noninvasive monitoring of the funct

关键词： Diffusion Tensor lmaging Magnetic Resonance Imaging Patellar Dislocation Vastus Medialis Oblique

Detection of the critical micelle concentration of cationic and anionic surfactants based on aggregation-induced emission property of hexaphenylsilole derivatives

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Science China Chemistry 2009年第6期52卷 755-759页

作者： TANG Li JIN JiaKe ZHANG Shuang MAO Yu SUN JingZhi YUAN WangZhang zhao hui XU HaiPeng QIN AnJun TANG Ben Zhong Department of Polymer Science and Engineering Institute of Biomedical MacromoleculesZhejiang UniversityHangzhou 310027China Department of Chemistry The Hong Kong University of Science&TechnologyHong KongChina

We report a fluorescence "turn-on" method to detect the critical micelle concentration (CMC) of surfactants. This method works well for both cationic and anionic surfactants. It employs an unprecedented mechanism (aggregation-induced emission, or AIE) to determine the CMC values, and the results are consistent with the data obtained by the classical techniques. In addition, this method renders the convenient detection of the CMC values. Any large and professional instruments are unnecessary, instead, a portable UV lamp and an ultrasonic generator are enough to carry out the detection in an ordinary laboratory. Considering that micelles are interesting entities and have found applications in many important fields such as emulsion polymerization, template of nanosized materials synthesis, controllable drug delivery and macromolecular self-assembling. Our experimental results may offer a facile, sensitive and promising method to detect the formation of micelles constructed by the new amphiphilic molecules and macromolecules.

关键词： aggregation-induced emission critical micelle concentration fluorescence probe

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大数据在食品安全监管风险预警中的运用

食品安全导刊 2024年第8期 20-23页

作者：刘辉赵珍珍于淼马晓迪韩修建景建民中检科(北京)测试技术有限公司北京102600

当前我国食品安全事件频繁发生,并且整体呈现出复杂化、动态化的发展趋势,对食品安全监管提出了新的挑战。食品安全风险预警是食品安全管理的核心部分,在实际开展相关工作的过程中,需要以预防为主、全面管控。我国食品行业的规模较大,... 详细信息

当前我国食品安全事件频繁发生,并且整体呈现出复杂化、动态化的发展趋势,对食品安全监管提出了新的挑战。食品安全风险预警是食品安全管理的核心部分,在实际开展相关工作的过程中,需要以预防为主、全面管控。我国食品行业的规模较大,大范围开展食品安全监管具有一定的难度,为此相关部门将大数据技术引入相关工作中,推动了食品安全监管现代化建设。基于此,本文分析现阶段国内食品安全风险预警情况,结合风险预警体系设计原则,总结出一些大数据在食品安全监管风险预警中的具体应用策略。

关键词：食品安全监管大数据风险预警

弹簧机构分闸锁扣系统对高压断路器分闸时间影响研究

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高压电器 2024年第8期60卷 37-42页

作者：惠勇锋段晓辉郭良超马琰刘宇何保营宋广民李美荣许家源牛平凯赵莉平高集团有限公司河南平顶山467001

高压断路器是电力系统中重要的保护和控制设备。高压断路器可以采用弹簧机构来执行分闸动作,断路器分闸时间是指处于合闸位置的断路器,从弹簧机构分闸脱扣器带电时刻到所有各极弧触头分离时刻的时间间隔。弹簧机构分闸脱扣器动作时间在... 详细信息

高压断路器是电力系统中重要的保护和控制设备。高压断路器可以采用弹簧机构来执行分闸动作,断路器分闸时间是指处于合闸位置的断路器,从弹簧机构分闸脱扣器带电时刻到所有各极弧触头分离时刻的时间间隔。弹簧机构分闸脱扣器动作时间在断路器分闸时间中占比50%左右,通过改变弹簧机构分闸锁扣器动作时间是调整断路器分闸时间关键因素。为有效调整断路器分闸时间,文中根据断路器分闸动作的原理,以高压断路器用弹簧机构分闸锁扣系统为研究对象,采用机械动力学仿真计算分析方法,分析分闸锁扣系统对断路器分闸时间的影响,并采用KOCOS机械特性测试仪和Phantom高速摄像机进行试验验证,并据此进行优化分析。结果表明,改变分闸锁扣系统中分闸一级锁闩结构对调整高压断路器分闸时间效果显著。对其他断路器或电气设备机械特性优化有一定的借鉴作用。

关键词：高压断路器弹簧机构分闸时间仿真计算

Expression and Emmprin Regulated Function of Aquaporinl in SMMC7221 Cells

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Chemical Research in Chinese Universities 2010年第4期26卷 578-582页

作者： LI Jiang ZHANG Ai-li TONG Qian ZHANG Jun-fang LI Hai-jing zhao Bing MA Tong-hui LI Xiao-men School of Life Sciences Northeast Normal University Changchun 130024 P. R. China Dental Hospital First Hospital Jilin University Changehun 130021 P. R. China Department of Cardiology First Hospital Jilin University Changehun 130021 P. R. China

Herein lie the crosstalk and regulation between AQP1 and Emmprin in SMMC7221 cells by means of siRNA technology and deglycosylation method. Firstly, HAQP1, rather than hAQP3. was selectively upregulated in SMMC7221 cells by FBS, flollowed by the upregulated expression of Emmprin. Emmprin gene silencing caused a remarkable change in the expression ofAQP1 gene, just like its downstream gene, MMP9, meanwhile the water permeability and cell migration were also descended prominently. Furthermore, when treated with tunicamycin, Emmprin was deglycosylated, which made the expression of AQP 1 significantly declined, followed by remarkably decreased cell membrane water permeability and cell migration. Taken together, all the data indicates the expression level and the modification of Emmprin by glycosylation are the key factors in regulating the expression of AQP1.

关键词： Aquaporinl Emmprin Cell migration

问题解决疗法联合经颅直流电治疗对老年卒中后抑郁患者康复效果的影响

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中国健康心理学杂志 2024年第6期32卷 849-853页

作者：赵晖刘智华刘永杰鲁圆圆李建丰高超河南省南阳市第四人民医院 473000 洛阳市第五人民医院

目的:探讨问题解决疗法联合经颅直流电治疗对老年卒中后抑郁患者康复效果的影响。方法:将纳入卒中后抑郁诊断标准的老年患者127例,依照随机数字表法进行分组,其中观察组64例,对照组63.,两组患者均给予内科常规治疗及护理,在此基础上,... 详细信息

目的:探讨问题解决疗法联合经颅直流电治疗对老年卒中后抑郁患者康复效果的影响。方法:将纳入卒中后抑郁诊断标准的老年患者127例,依照随机数字表法进行分组,其中观察组64例,对照组63.,两组患者均给予内科常规治疗及护理,在此基础上,对照组患者给予经颅直流电治疗,观察组患者给与问题解决疗法联合经颅直流电治疗。采用汉密尔顿抑郁量表(HAMD-17)、脑卒中自我管理行为评定量表(SSMBS)、简易智力状态检查量表(MMSE)、美国国立卫生研究院卒中量表(NIHSS)、改良Barthei指数(MBI)、慢性疾病病耻感量表简版(SSCI-8)评估两组患者治疗前、治疗4周末得分。结果:两组脱落率比较,观察组的脱落率为3.12%,对照组的脱离率为4.76%,差异无统计学意义(P>0.05);两组有效率比较,观察组的有效率为91.2%,对照组有效率76.7%,差异具有显著的统计学意义(χ^(2)=5.407,P3..842,-3..005,-26.023.P3.916,P3.220,2.569;P3.3.2,18.921,27.566,P3.63.,-3.292,-7.913.P<0.01)。结论:问题解决疗法联合经颅直流电干预模式可有效的改善老年卒中后抑郁情绪、认知功能及病耻感,促进患者的神经功能的康复,提高患者的自我管理行为及日常生活能力。

关键词：问题解决疗法经颅直流电治疗老年患者卒中后抑郁

A Fractal Method of Estimating Soil Structure Changes Under Different Vegetations on Ziwuling Mountains of the Loess Plateau,China

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Agricultural Sciences in China 2006年第7期5卷 530-538页

作者： zhao Shi-wei SU Jing YANG Yong-hui LIU Na-na WU Jin-shui SHANGGUAN Zhou-ping Institute of Soil and Water Conservation Northwest A ＆ F University Yangling 712100 P.R.China State Key Laboratory of Soil Erosion and Dryland Agriculture Institute of Soil and Water Conservation the Chinese Academy of Sciences Yangling 712100 P.R.China College of Resources and Environment Northwest A ＆ F University Yangling 712100 P.R.China Institute of Subtropical Agriculture the Chinese Academy of Sciences Changsha 410125 P.R.China

Fractal method is a new method to estimate soil structure. It has been shown to be a useful tool in studies related to physical properties of soil as well as erosion and other hydrological processes. Fractal dimension was used to study the soil structure in soil at different stages of vegetative succession on the Ziwuling Mountains. The land use and vegetation types included cultivated land, abandoned land, grassland, two types of shrub land, and three types of forests. The grassland, shrub land, and forested areas represented a continuum in vegetative succession that had occurred naturally, as the land was abandoned in 1862. Disturbed and undisturbed soil samples were collected from ten vegetation types from depths of 0-10, 10-20, and 20-3. cm on the Ziwuling Mountains, at a site with an elevation of about 1 500 m. Particle size distribution was determined by the pipette method and aggregate size distribution was determined by wet sieving. The results were used to calculate the particle and aggregate fractal dimension. The results showed that particle and aggregate fractal dimensions varied between vegetation types. There was a positive correlation between the particle fractal dimension and the weight of particles with diameter 〈 0.001 mm, but no relationship between particle fractal dimension and the other particle size classes. Particle fractal dimension was lower in vegetated soils compared to cropland and there was no consistent relationship between fractal dimension and vegetation type. Aggregate fractal dimension was positively correlated with the weight of 〉 0.25 mm aggregates. Aggregate fractal dimension was lower in vegetated soils compared with cropland. In contrast to particle fractal dimension, aggregate fractal dimension described changes in soil structure associated with vegetative succession. The results of this study indicate that aggregate fractal dimension is more effective in describing soil structure and function compared with particle fractal d

关键词： soil fractal dimension soil particle soil aggregate vegetation type Ziwuling Mountains