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Effect of crystallization temperature and propylene sequence length on the crystalline structure of propylene-ethylene random copolymers

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Chinese Science Bulletin 2008年第12期53卷 1804-1812页

作者： GOU QingQiang li huihui YU ZhenQiang CHEN ErQiang ZHANG YuDong YAN ShouKe Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Department of Polymer Science School of Chemistry Peking University Beijing 100871 China Beijing Research Institute of Chemical Industry SINOPEC Beijing 100013 China candidate of Graduate University of Chinese Academy of Sciences Beijing100039 China

Crystallization behavior and resultant crystalline structure of a series of temperature-rising elu-tion-fractionated specimen of a Ziegler-Natta catalyst-synthesized propylene-ethylene random co-polymer were studied by DSC, WAXD and AFM. The experimental results indicate that both crystalliza-tion temperature and propylene sequence length exhibit great influence on the crystallization behavior and crystalline structure of the copolymer. It was found that the ethylene co-monomers acting as point defects inserted into the polypropylene chains play an important role in the formation of γ-iPP. As the co-monomer content increases, the crystallizable sequence length of iPP decreases, which produces an appropriate condition for its γ crystallization. At the same time, the existence of chain defects leads to a lower crystallinity of the copolymer and imperfection of the resultant crystals. For each individual sample with certain propylene sequence length or ethylene content, the increment of γ-iPP crystal content with increasing crystallization temperature demonstrates that higher crystallization tempera-ture is in favor of the γ-iPP crystallization. Pure γ-iPP crystals have been got in samples with propylene sequence length lower than 21 under suitable crystallization conditions.

关键词：结晶温度晶体乙烯共聚物

Lateral Hypothalamic Area Glutamatergic Neurons and Their Projections to the Lateral Habenula Modulate the Anesthetic Potency of Isoflurane in Mice

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Neuroscience Bulletin 2021年第7期37卷 934-946页

作者： Shiyi Zhao Rui li Huiming li Sa Wang Xinxin Zhang Dan Wang Juan Guo huihui li Ao li Tingting Tong Haixing Zhong Qianzi Yang Hailong Dong Department of Anesthesiology and Perioperative Medicine Xijing HospitalFourth Military Medical UniversityXi’an 710032China

The lateral hypothalamic area(LHA)plays a pivotal role in regulating consciousness transition,in which orexinergic neurons,GABAergic neurons,and melanin-concentrating hormone neurons are *** neurons have a large population in the LHA,but their anesthesia-related effect has not been ***,we found that genetic ablation of LHA glutamatergic neurons shortened the induction time and prolonged the recovery time of isoflurane anesthesia in *** contrast,chemogenetic activation of LHA glutamatergic neurons increased the time to anesthesia and decreased the time to *** activation of LHA glutamatergic neurons during the maintenance of anesthesia reduced the burst suppression pattern of the electroencephalogram(EEG)and shifted EEG features to an arousal *** of LHA glutamatergic projections to the lateral habenula(LHb)also facilitated the emergence from anesthesia and the transition of anesthesia depth to a lighter ***,LHA glutamatergic neurons and their projections to the LHb regulate anesthetic potency and EEG features.

关键词： Anesthesia Isoflurane Lateral hypothalamic area Lateral habenula Glutamatergic neuron

Overcoming multidrug resistance(MDR) in cancer by nanotechnology

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Science China Chemistry 2010年第11期53卷 2226-2232页

作者： BU huihui,GAO Yu & li YaPing Shanghai Institute of Materia Medica,Chinese Academy of Sciences,Shanghai 201203,China Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai China

The emerging nanotechnology-based drug delivery holds tremendous potential to deliver chemotherapeutic drugs for treatment of multidrug resistance(MDR) *** drug delivery system could improve the pharmacokinetic behavior of antitumor drugs,deliver chemotherapeutic drugs to target sites,control release of drugs,and reduce the systemic toxicity of drugs in MDR *** review addresses the use of nanotechnology to overcome MDR classified on the bases of the fundamental mechanisms of MDR and various approaches to deliver drugs for treatment of MDR cancer.

关键词： nanotechnology nanoparticles multidrug resistance chemotherapeutic drugs cancer drug delivery system

新时代乡村小规模学校问题研究的逻辑进路与方法论原则

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中国教育学刊 2022年第2期 65-70页

作者：满忠坤李慧慧聊城大学教育科学学院山东聊城252000 天津师范大学教育学部天津300387

伴随乡村振兴战略的纵深推进和城乡教育一体化阶段性目标的时代诉求,乡村小规模学校问题依旧是制约我国基础教育公平和优质均衡发展的现实难题。澄明新时代乡村小规模学校作为问题的内在诉求,梳理辨明相关研究的逻辑进路与核心关切,确... 详细信息

伴随乡村振兴战略的纵深推进和城乡教育一体化阶段性目标的时代诉求,乡村小规模学校问题依旧是制约我国基础教育公平和优质均衡发展的现实难题。澄明新时代乡村小规模学校作为问题的内在诉求,梳理辨明相关研究的逻辑进路与核心关切,确证推进小规模学校问题研究的方法论原则,是促进新时代乡村小规模学校高质量发展的重要保障。

关键词：乡村小规模学校价值诉求逻辑进路方法论原则

Modeling and simulation of recurrent phenotypic and genomic selections in plant breeding under the presence of epistasis

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The Crop Journal 2020年第5期8卷 866-877页

作者： Mohsin Ali Luyan Zhang Ian DeLacy Vivi Arief Mark Dieters Wolfgang H.Pfeiffer Jiankang Wang huihui li National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China School of Agriculture and Food Sciences The University of QueenslandBrisbaneQLD 4072Australia HarvestPlus Challenge Programme c/o International Food Policy Research Institute(IFPRI)1201 Eye StNWWashingtonDC 20005USA

Recurrent selection is an important breeding method for population improvement and selecting elite inbreds or fixed lines from the improved ***,a computer simulation tool called QuMARS has been developed,which allows the simulation and optimization of various recurrent selection *** major objective in this study was to use the QuMARS tool to compare phenotypic recurrent,marker-assisted recurrent,and genomic selections(abbreviated respectively as PS,MARS and GS)for both short-and long-termbreeding ***,twomarker selection models were considered,i.e.,stepwise(Rstep)and forward regressions(Forward).For GS,three prediction models were considered,i.e.,genomic best linear unbiased predictors(GBLUP),ridge regression(Ridge),and regression by Moore-Penrose general inverse(InverseMP).To generate genotypes and phenotypes for a given individual during simulation,one additive and two epistasis genetic models were considered with three levels of *** demonstrated that selection responses from GBLUP-based GS and MARS(Forward)were consistently greater than those from PS under the additive model,particularly in early selection *** contrast,selection response from PS was consistently superior over MARS and GS under epistatic *** the two epistasis models,total genetic variance and the additive variance component were increased in some cases after *** simulation,we concluded that GS and PS were effective recurrent selection methods for improved breeding of targeted traits controlled by additive and epistatic quantitative trait loci(QTL).QuMARS provides an opportunity for breeders to compare,optimize and integrate new technology into their conventional breeding programs.

关键词： breeding elite additive

Natural variation of GmFNSII-2 contributes to drought resistance by modulating enzyme activity in soybean

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The Crop Journal 2024年第2期12卷 529-539页

作者： huihui Gao Pengcheng Wei Yongzhe Gu Pengbin Tang Yifan Shen Lei Yang linxin Dong Haowei Zheng Kuo Shu Mayamiko Masangano Bin Dong Long Miao Jiajia li lijuan Qiu Xiaobo Wang School of Agronomy Anhui Agricultural UniversityHefei 230036AnhuiChina State Key Laboratory of Crop Gene Resources and Breeding The National Key Facility for Crop Gene Resources and Genetic Improvement(NFCRI)/Key Laboratory of Crop Gene Resource and Germplasm Enhancement(MOA)Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

As an essential crop that provides vegetable oil and protein,soybean(Glycine max(L.)Merr.)is widely planted all over the ***,the scarcity of water resources worldwide has seriously impacted on the quality and yield of *** address this,exploring excellent genes for improving drought resistance in soybean is *** this study,we identified natural variations of GmFNSII-2(flavone synthase II)significantly affect the drought resistance of *** sequence analysis of GmFNSII-2 in 632 cultivated and 44 wild soybeans nine haplotypes were *** full-length allele GmFNSII-2^(C),but not the truncated allele GmFNSII-2^(A) possessing a nonsense nucleotide variation,increased enzyme *** research found that GmDREB3,known to increase soybean drought resistance,bound to the promoter region of GmFNSII-2^(C).GmDREB3 positively regulated the expression of GmFNSII-2^(C),increased flavone synthase abundance and improved the drought ***,a singlebase mutation in the GmFNSII-2^(C) promoter generated an additional drought response element(CCCCT),which had stronger interaction strength with GmDREB3 and increased its transcriptional activity under drought *** frequency of drought-resistant soybean varieties with Hap 1(Pro:GmFNSII-2^(C))has increased,suggesting that this haplotype may be selected during soybean *** summary,GmFNSII-2^(C) could be used for molecular breeding of drought-tolerant soybean.

关键词： Drought stress Flavone synthase GmFNSII-2 Natural variation Drought response element

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单电感双输出Buck变换器的微分平坦控制

电力系统及其自动化学报 2023年第5期35卷 104-110,137页

作者：李慧慧皇金锋陕西理工大学电气工程学院汉中723001

为克服传统PI控制单电感双输出SIDO(single-inductor dual-output)开关变换器输出端存在交叉影响严重、暂态响应速度慢等问题,提出一种降维状态观测器补偿的微分平坦控制策略。首先根据微分平坦理论,分别设计支路开关管的电压控制和主... 详细信息

为克服传统PI控制单电感双输出SIDO(single-inductor dual-output)开关变换器输出端存在交叉影响严重、暂态响应速度慢等问题,提出一种降维状态观测器补偿的微分平坦控制策略。首先根据微分平坦理论,分别设计支路开关管的电压控制和主开关管的电流控制,并对平坦输出量采用PI控制器进行误差反馈补偿。其次根据变换器的状态空间平均模型,对负载电流设计降维状态观测器,并将观测值作用于平坦系统,以提升系统暂态性能。最后搭建了实验平台进行验证,结果表明,所提控制具有更快的暂态响应速度,同时有效减小了交叉影响。

关键词：单电感双输出交叉影响状态空间平均模型微分平坦状态观测器

Degradation of 2,4,6-trichlorphenol by producing hydrogen using ultrasonic mist generated from photocatalysts suspension

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Emerging Contaminants 2020年第1期6卷 155-161页

作者： huihui li Xin Chang Yuanzheng Zhang Siyao Zhang Yunrong Dai lifeng Yin State Key Laboratory of Environment Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing100875PR China School of Water Resources and Environment School of Scientific ResearchChina University of GeosciencesBeijing100083PR China

Photocatalytic hydrogen production synergized with the oxidation of pollutants is an environmentally friendly and economical approach to generate clean energy and remove the pollution from *** this study,photocatalytic hydrogen production cooperating with 2,4,6-trichlorophenol(2,4,6-TCP)degradation have been reinforced by introducing an ultrasonic *** degradation of 2,4,6-TCP in a mist of three photocatalysts(g-C3N4,TiO2,and Bi2O3)generated by ultrasonic atomization was performed under 254 nm ultraviolet(UV254)light *** results showed that,under UV254 irradiation,three different photocatalysts(g-C3N4,TiO2,and Bi2O3)all accelerated both hydrogen production and 2,4,6-TCP ***,2,4,6-TCP degradation and photocatalytic hydrogen production exhibited an obvious synergistic effect,since 2,4,6-TCP has a strong tendency to react with photo-generated holes and their second radicals so as to inhibit the recombination of carriers,and thus improved the efficiency of hydrogen production ***,by introducing ultrasonic atomization,the atomized droplets acted as micro-photocatalytic units to replace the macrophotocatalytic reaction ***,the mass transfer distance for free radicals was restricted and the utilization of light energy by photocatalysts was ***,the reaction efficiency was *** results reveal environmentally friendly and economical potential of hydrogen production by photocatalytic degradation of 2,4,6-TCP in atomized droplets.

关键词： Ultrasonic atomization Photocatalysis Hydrogen production 2,4,6-Trichlorophenol Degradation

涂覆石墨烯的混合型电介质纳米并行线波导的模式特性分析

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光学学报 2022年第13期42卷 172-181页

作者：李宁薛文瑞董慧莹李慧慧李昌勇山西大学物理电子工程学院山西太原030006 量子光学与光量子器件国家重点实验室山西大学激光光谱研究所山西太原030006 极端光学协同创新中心山西大学物理电子工程学院山西太原030006

设计了一种涂覆石墨烯的混合型电介质纳米并行线波导。这种波导由两根圆柱形和一根椭圆柱形电介质纳米并行线组成。利用有限元方法对5个最低阶模式进行了分类,研究了工作波长、石墨烯的费米能和结构参数对5个最低阶模式的有效折射率实... 详细信息

设计了一种涂覆石墨烯的混合型电介质纳米并行线波导。这种波导由两根圆柱形和一根椭圆柱形电介质纳米并行线组成。利用有限元方法对5个最低阶模式进行了分类,研究了工作波长、石墨烯的费米能和结构参数对5个最低阶模式的有效折射率实部、传播长度和品质因数的影响。结果表明:5个最低阶模式均可由圆柱形纳米线和椭圆柱形纳米线的低阶模合成。当调节工作波长和石墨烯的费米能时,5个模式的传输特性均可得到有效的调节。当结构参数变化时,前两个模式的传输特性变化比较显著,而其他三个模式的传输特性变化不明显。将所设计结构与由两根椭圆柱形和一根圆柱形电介质纳米并行线构成的波导相比较,发现所设计的结构具有更长的传播长度和更高的品质因数。该研究为涂覆石墨烯的混合型电介质纳米并行线波导的设计、制作和应用提供了参考。

关键词：表面光学石墨烯纳米线波导表面等离激元有限元方法