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Chinese Chemical Letters 2017年第5期28卷 960-962页

作者： chen-xi bai Feng Shen xin-Hua Qi College of Environmental Science and Engineering Nankai UniversityTianjin 300071China Agro-Environmental Protection Institute Chinese Academy of Agricultural SciencesTianjin 300191China

Hydrothermal carbonization of biomass is a promising method to prepare carbonaceous ***,post physical or chemical activation is necessary to increase surface area and porosity of the ***,porous carbonaceous material（FPC） with large surface area（481.7 m^2/g） and pore volume（0.73 cm^3/g） was prepared directly from hydrothermal carbonization of fructose and phloroglucinol in hydroalcoholic *** characteristics of the FPC and its adsorption capacity for a representative antibiotic tetracycline in aqueous solution were *** work provides a green and efficient method to fabricate porous carbonaceous adsorbent that has great potential applications in chemical and environmental fields.

关键词： Fructose Carbon materials Porous materials Adsorption Hydrothermal carbonization

Neodymium Organic Sulfonate Complexes: Tunable Electronegativity/Steric Hindrance and Application in Controlled Cis-1,4-polymerization of Butadiene

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Chinese Journal of Polymer Science 2019年第3期37卷 208-215页

作者： Jian-Yun He Long Cui Yan-Long Qi Quan-Quan Dai chen-xi bai Key Laboratory of High-Performance Synthetic Rubber and its Composite Materials Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Rare earth catalysts possessing characteristics of cation-anion ion pair show advantages of adjusting electronegativity and steric hindrance of metal active sites, which can control the catalytic performance and stereoselectivity better than those of traditional metallocene and Ziegler-Natta catalysts in diene polymerization. In this work, a series of neodymium organic sulfonate complexes,Nd(CF_3SO_3)_3·x H_2O·y L(x, y: the coordination number; L refers to an organic electron donating ligand, such as acetylacetone(acac), isooctyl alcohol(IAOH), tributyl phosphate(TBP), etc.), have been synthesized to form the cationic active species in the presence of alkylaluminum such as Al(i-Bu)_3, AlEt_3, and Al(i-Bu)_2H, which display high activities and distinguishing cis-1,4 selectivities(up to99.9%) for the polymerization of butadiene. The microstructures, yield, molecular weight, and molecular weight distribution of the resulting polymer are well controlled by adjusting electronegativity/steric hindrance of the complexes. In addition, the kinetics, active species, and the possible process of polymerization are also discussed in this article.

关键词： Neodymium catalysts Organic sulfonate complexes Tunable electronegativity and steric hindrance Cis-1,4-polymerization Butadiene

Polymerization of 1,3-Butadiene Catalyzed by Cobalt(Ⅱ) and Nickel(Ⅱ) Complexes Bearing Pyridine-2-imidate Ligands

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Chinese Journal of Polymer Science 2016年第9期34卷 1060-1069页

作者： Heng Liu Shi-ze Yang Feng Wang chen-xi bai 胡雁鸣张学全 Key Laboratory of Synthetic Rubber Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Panjin Northern Asphalt Co. LtdNorinco GroupPanjin 124000China

Cobalt and nickel complexes （la-ld and 2a-2d, respectively） supported by 2-imidate-pyridine ligands were synthesized and used for 1,3-butadiene polymerization. The complexes were characterized by IR and element analysis, and complex la was further characterized by single-crystal X-ray diffraction. The solid state structure of complex la displayed a distorted tetrahedral geometry. Upon activation with ethylaluminum sesquichloride （EASC）, all the complexes showed high activities toward 1,3-butadiene polymerization. The cobalt complexes produced polymers with high cis-1,4 contents and high molecular weights, while the nickel complexes displayed low cis-l,4 selectivity and the resulting polymers had low molecular weights. The catalytic activities of the complexes highly depended on the ligand structure. With the increment of polymerization temperature, the cis-1,4 content and the molecular weight of the resulting polymer decreased.

关键词： 1,3-Butadiene Late-transition metal Cis-1,4-polybutadiene Pyridine-2-imidate.

Comparison of the Kinetics of 1-Hexene Metathesis by Ruthenium Carbene Catalysts

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Chinese Chemical Letters 2006年第7期17卷 988-990页

作者： chen xi bai Wen Zhen ZHANG Ren HE Yan Hong SUN xiao Ping CAI Research Institute of Jilin Petrochemical Company Ltd. Petrochina Jilin 132021 State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

A kinetic study of two ruthenium carbene catalysts, （PCy3）2Cl2Ru=CHPh 1 （Grubbs catalyst） and a new catalyst [1,3-bis（2,6-dimethylphenyl）4,5-dihydroimidazol-2-ylidene]（PPh3）（Cl）2Ru-CHPh 3, were conducted in metathesis of 1-hexene. The kinetic behavior of these catalysts at 40, 50, 60 and 70℃ was compared. Complex 3 has the more active catalytic effect at temperatures 40-70℃.

关键词： Ruthenium carbene metathesis.

Rapid assessment of knowledge,attitudes,practices,and risk perception related to the prevention and control of Ebola virus disease in three communities of Sierra Leone

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Infectious Diseases of Poverty 2016年第1期5卷 447-452页

作者： Hai Jiang Guo-Qing Shi Wen-xiao Tu Can-Jun Zheng Xue-Hui Lai xin-Xu Li Qiang Wei Mei Li Li-Quan Deng xiang Huo Ming-Quan chen Feng Xu Long-Jie Ye xi-chen bai Tong-Nian chen Shao-Hua Yin Thomas T.Samba xiao-Feng Liang State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Institute for Communicable Disease Control and PreventionBeijing 102206China Chinese Center for Disease Control and Prevention Beijing 102206China ITERP Beijing 102206China District Health Management Team Western AreaMinistry of Health and SanitationFreetownSierra Leone

Background:The recent outbreak of the Ebola virus disease(EVD)in Sierra Leone has been characterized by the World Health Organization as one of the most challenging EVD outbreaks to *** first confirmed case in Sierra Leone was a young woman who was admitted to a government hospital in Kenema following a miscarriage on 24 May *** 5 January 2015,intensified training for an EVD response project was initiated at the medical university of Sierra Leone in *** understand the knowledge,attitudes,practices,and perceived risk of EVD among the public,especially after this training,a rapid assessment was conducted from 10 to 16 March ***:Interviews were conducted with 466 participants based on questionnaires that were distributed from 10 to 16 March 2015 by cluster sampling in three adjacent communities,namely Jui,Grafton,and Kossoh Town,in the Western Area Rural District of Sierra ***:It was found that knowledge about EVD was comprehensive and *** attitude towards prevention was found to be *** all participants knew the reporting phone number 117 and had reported some change in behavior since learning about *** than half(62%)of the participants had a history of travelling to urban areas,which increases the risk of *** multivariable logistic regression analysis showed that community and occupation were variables associated with perceived risk of ***:Our study showed that community level social mobilization and community engagement were an effective strategy in the special context.

关键词： Knowledge Attitude Practice Risk perception ITERP Ebola Sierra Leone

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奶山羊实验性乳房炎二维超声显像初步观察

中国兽医科技 2000年第5期30卷 31-32页

作者：白朝勇陈白希华南农业大学动物医学系广东广州510642

通过对奶山羊实验性急性乳房炎的二维超声显像观察 ,结果表明这项技术能充分显示乳房炎的急性炎症变化 ,呈现的组织水肿和肿胀增厚明显 ,与对照的正常乳房比较 ,图像清晰可辨。其炎症发展的动态变化为 :灌注大肠埃希氏菌内毒素后 ,2 10... 详细信息

通过对奶山羊实验性急性乳房炎的二维超声显像观察 ,结果表明这项技术能充分显示乳房炎的急性炎症变化 ,呈现的组织水肿和肿胀增厚明显 ,与对照的正常乳房比较 ,图像清晰可辨。其炎症发展的动态变化为 :灌注大肠埃希氏菌内毒素后 ,2 10min组织渗出水肿达到顶峰并持续至灌注后 3 5 0min ;以后回声强度逐渐减弱 ,2

关键词：奶山羊急性乳房炎二维超声显像诊断

NIR photothermal enhancement to achieve high-efficiency nitrogen reduction to ammonia by polyoxometalates@Fe-polydopamine

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Nano Research 2025年第1期18卷 118-128页

作者： xiaofei chen Lixin Wu Feng bai Key Laboratory for Special Functional Materials of Ministry of Education National&Local Joint Engineering Research Center for High-Efficiency Display and Lighting TechnologySchool of Nanoscience and Materials EngineeringHenan UniversityKaifeng 475004China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The development of atmospheric pressure N_(2)reduction to NH_(3)is attracting much attention in green chemistry,yet it is still a challenge to obtain satisfactory activity under mild ***,an efficient near-infrared(NIR)photothermal catalysis reduction of N_(2)constitutes an occurrence is *** or without V-substitute polyoxometalates(POMs)loaded on the surface of Fechelated polydopamine(Fe-PDA)photothermal support through the electrostatic interactions,NIR photothermal catalysts POMs@Fe-PDA are *** induction of“FeV”cofactor facilitates electron transfer between V(V)/V(IV)&Fe(III)/Fe(II)and N_(2),thereby activating N_(2)*** synergy between the catalytic activity of V-POMs and the local NIR photothermal effect of Fe-PDA dramatically enhances N_(2)***,PMo_(10)V_(2)@Fe-PDA exhibits a significantly enhanced NH_(3)production rate of 181.1μmol·LN^(-1)with a turnover frequency of 1006.1 mmol·MN^(-1)·hN^(-1)under 808 nm NIR laser radiation,being the highest values reported at atmospheric *** expect that this work could provide an alternative approach for photothermal catalysis N_(2)reduction under mild conditions.

关键词： polyoxometalate near-infrared photothermal catalysis N_(2)reduction mild condition

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聚氨基酸接枝聚异戊二烯的仿生合成与性能

高分子学报 2023年第5期54卷 593-600页

作者：冯展威代全权贺剑云白晨曦中国科学院长春应用化学研究所、中国科学院高性能合成橡胶及其复合材料重点实验室长春130022 中国科学技术大学应用化学与工程学院合肥230026

通过硫醇-烯点击反应将2-氨基乙硫醇接枝到聚异戊二烯主链上合成带有氨基侧链的聚异戊二烯,再通过侧链氨基引发L-缬氨酸-N-硫代羧基内酸酐(Val-NTA)单体和β-苯丙氨酸-N-硫代羧基内酸酐(β-Phe-NTA)单体的聚合,制备出2种方式改性的聚异... 详细信息

通过硫醇-烯点击反应将2-氨基乙硫醇接枝到聚异戊二烯主链上合成带有氨基侧链的聚异戊二烯,再通过侧链氨基引发L-缬氨酸-N-硫代羧基内酸酐(Val-NTA)单体和β-苯丙氨酸-N-硫代羧基内酸酐(β-Phe-NTA)单体的聚合,制备出2种方式改性的聚异戊二烯.其中,Val-NTA聚合接枝聚异戊二烯的拉伸强度28.6 MPa,300%定伸强度18.9 MPa,相比天然橡胶分别提升10.7%和9.3%.β-Phe-NTA聚合接枝聚异戊二烯的拉伸强度28.0 MPa,比天然橡胶提升8.3%.

关键词：聚氨基酸接枝聚异戊二烯硫醇-烯点击反应仿生合成橡胶硫代羧基内酸酐

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man Han Deyang Zeng Wei Tan xingxing chen Shuyuan bai Qiong Wu Yushan chen Zhen Wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

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定性仿真技术及应用

系统仿真学报 2004年第2期16卷 202-209页

作者：邵晨曦白方周中国科学技术大学计算机科学技术系合肥230027

定性仿真以非数字化手段处理信息输入、建模、行为分析和结果输出等仿真环节,通过定性建模推导系统的定性行为描述。定性仿真是处理不完备信息的有效方法。定性仿真方法产生了多种流派,如模糊仿真法、归纳推理法、非因果关系推理方法、... 详细信息

定性仿真以非数字化手段处理信息输入、建模、行为分析和结果输出等仿真环节,通过定性建模推导系统的定性行为描述。定性仿真是处理不完备信息的有效方法。定性仿真方法产生了多种流派,如模糊仿真法、归纳推理法、非因果关系推理方法、基于因果关系的推理方法、基于图表的推理方法、基于数据的结构化建模方法、基于定性空间的推理方法等。近年来,定性仿真已应用到故障诊断、生态和环境学、机械制造业和工业系统、医学研究、混杂非线性系统、教育系统、人类社会与经济、人工智能等领域中。最后从整体上简要评述了定性仿真的发展。

关键词：定性仿真定性建模定性推理定性仿真应用