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灵宝杜鹃种子特性及赤霉素对其萌发的影响

洛阳师范学院学报 2024年第2期43卷 23-26,51页

作者：于相丽韩军旺周晓君洛阳师范学院生命科学学院河南洛阳471934 河南小秦岭国家级自然保护区管理中心河南三门峡472500

以灵宝杜鹃种子为材料,对灵宝杜鹃种子形态特征、吸水性以及赤霉素处理对种子发芽的影响进行了研究.结果表明,灵宝杜鹃种子呈锥状,为小型种子;吸水过程中,0~2 h种子吸水速度最快,随后吸水速度迅速降低,至18 h达到饱和状态.GA_(3)浸泡处... 详细信息

以灵宝杜鹃种子为材料,对灵宝杜鹃种子形态特征、吸水性以及赤霉素处理对种子发芽的影响进行了研究.结果表明,灵宝杜鹃种子呈锥状,为小型种子;吸水过程中,0~2 h种子吸水速度最快,随后吸水速度迅速降低,至18 h达到饱和状态.GA_(3)浸泡处理能提高种子发芽率和发芽势,提高了种子的发芽速度和整齐度,但浸种时间影响不大;灭菌处理影响种子发芽,采取先用8%NaClO灭菌后用GA_(3)处理的方法可以显著提高发芽率.

关键词：灵宝杜鹃发芽率 GA 3

Formation of the structure-Ⅱgas hydrate from low-concentration propane mixed with methane

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Chinese Journal of Chemical Engineering 2023年第6期58卷 306-314页

作者： Sanya Du xiaomin han Wenjiu Cai Jinlong Zhu xiaobai Ma Songbai han Dongfeng Chen yusheng Zhao Hui Li Hailong Lu xiaohui yu Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Engineering Peking UniversityBeijing 100871China Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing 100871China Department of Physics Southern University of Science and Technology(SUSTech)Shenzhen 518055China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413China Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology(SUSTech)Shenzhen 518055China Songshan Lake Materials Laboratory Dongguan 523808China

It has been recognized that a small amount of propane mixed with methane can change greatly in not only the thermodynamics but also the structural properties of gas ***,its mechanism is still not well understood *** this research,structure-Ⅱ(sⅡ)hydrate is synthesized using a methanepropane gas mixture with an initial mole ratio of 99:1,and it is found that large(5~(12)6~4)cages are cooccupied by multiple gases based on the rigid structure analysis of neutron diffraction *** first principles calculation and molecular dynamics simulation are conducted to uncover the molecular mechanism for sⅡmethane-propane hydrate formation,revealing that the presence of propane inhibits the formation of structure-Ⅰ(sⅠ)hydrate but promotes sⅡhydrate *** results help to understand the accumulation mechanism of natural gas hydrate and benefit to optimize the condition for gas storage and transportation in hydrate form.

关键词： Multiple guest molecules Clathrates Neutron powder diffraction Structural transformation Molecular mechanism

Enhanced pitting corrosion resistance of CoCrFeMnNi high entropy alloy in the presence of Desulfovibrio vulgaris via nitrogen doping

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Journal of Materials Science & Technology 2023年第8期139卷 92-102页

作者： Chuntian Yang Hao Feng xiaobo Chen yu han Huabing Li Dake Xu Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang110819China School of Engineering RMIT UniversityCarltonVIC 3053Australia School of Metallurgy Northeastern UniversityShenyang110819China

Corrosion-resistant high nitrogen high entropy alloys(HEAs)were manufactured by pressurized *** work revealed the inhibitory effect of nitrogen on pitting corrosion of HEAs caused by sul-fate reducing bacterium Desulfovibrio *** indicated that HEA-0 N was susceptible to pitting corrosion and sulfidation under attack of ***,whereas the addition of nitrogen significantly de-creased the pitting *** potentials of HEA-0.52 N and HEA-1.23 N increased by 133%and 171%,respectively compared to HEA-0 N in the presence of SRB.X-ray photoelectron spectroscopy results unveiled that nitrogen enriched in passive film and strengthened it by increasing fraction of Cr_(2)O_(3)and Fe^(3+)_(ox).Surface of the nitrogen-alloyed HEAs exhibited less defective passive films as revealed by Mott-Schottky *** doping provides a novel insight into the design of microbial corrosion resistant HEA.

关键词： High entropy alloy Microbiologically influenced corrosion Sulfate reducing bacteria Nitrogen doping Pitting corrosion

Construction of three stereocenters via hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones

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Science China Chemistry 2021年第2期64卷 232-237页

作者： Yi-Xuan Ding Zhou-Hao Zhu han Wang Chang-Bin yu Yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A Ru-catalyzed hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones was developed for construction of three stereocenters including two coherent and discontiguous chiral centers and a chiral quaternary carbon with excellent enantio-and *** synthesis of four stereoisomers could be conducted with high *** desymmetrization could be achieved at gram scale without loss of reactivity and optical purity,and a formal synthesis of bioactive molecule(-)-isocelorbicol was completed.

关键词： desymmetrization hydrogenation 1,3-cyclohexanediones three stereocenters chiral quaternary carbon

In-situ TEM Observation of Cementite Coarsening Behavior of 5Mn Steel during Tempering

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Journal of Iron and Steel Research International 2016年第5期23卷 442-446页

作者： Ye xiA xi-nan LUO xiao-yan ZHONG Hui-hua ZHOU Cun-yu WANG Jie SHI National Center for Electron Microscopy in Beijing School of Materials Science and EngineeringKey Laboratory of Advanced Materials(MOE)The State Key Laboratory of New Ceramics and Fine ProcessingTsinghua UniversityBeijing 100084China Central Iron and Steel Research Institute Beijing 100081China

The cementite formation and coarsening behaviors of 0. 2 mass% C-5 mass% Mn steel during tempering at 500℃ were investigated by in-situ transmission electron microscope（ TEM）. In-situ TEM observation showed uniform distribution of cementite particles at the early stage of tempering in the rapidly heated（ 500 ℃ / s） sample. Elemental analysis confirmed that the cementite growth was dominated by Mn diffusion. During the cementite growth,the coarsening behavior of intragranular cementite was significantly controlled by the matrix diffusion,while that of the intergranular cementite was mainly governed by the boundary diffusion. The in-situ TEM observation revealed that the dislocation pipe diffusion of Mn took place during tempering,which accelerated the Mn diffusion between cementite particles. The coarsening rates of individual cementite particles were calculated based on the in-situ TEM observation.

关键词： in-situ observation cementite coarsening behavior Mn diffusion 5Mn steel tempering

弱制度东道国情境下中药产业生态系统的构建——基于“一带一路”视角

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科技和产业 2024年第1期24卷 84-88页

作者：余孝敬韩旭东李爱玉安徽中医药大学医药经济管理学院合肥230012 数据科学与中医药创新发展安徽省哲学社会科学重点实验室合肥230012

“一带一路”正步入高质量发展新时期,为中国中医药行业的国际化发展带来了难得的机遇。随着中药产业国际市场的不断开拓,中国与共建“一带一路”国家广泛开展中医药合作,构建中药产业生态系统。沿线国家制度质量对中国中药产业生态系... 详细信息

“一带一路”正步入高质量发展新时期,为中国中医药行业的国际化发展带来了难得的机遇。随着中药产业国际市场的不断开拓,中国与共建“一带一路”国家广泛开展中医药合作,构建中药产业生态系统。沿线国家制度质量对中国中药产业生态系统的构建产生了直接或间接的影响。基于“一带一路”视角,对我国中药产业国际化进行研究分析,探究如何在弱制度东道国情境下构建中药产业生态系统,并提供合理路径选择。

关键词：中药产业一带一路中药产业生态系统弱制度东道国

Developing the QSPR model for predicting the storage lipid/water distribution coefficient of organic compounds

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Frontiers of Environmental Science & Engineering 2021年第2期15卷 87-94页

作者： Miao Li Jian Li yuchen Lu Cenyang han xiaoxuan Wei Guangcai Ma Haiying yu College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China

The distribution of organic compounds in stored lipids affects their migration,transformation,bioaccumulation,and toxicity in *** storage lipid/water distribution coefficient(log K_(lip/w))of organic chemicals,which quantitatively determines such distribution,has become a key parameter to assist their ecological security and health *** to the impossibility to measure K_(lip/w)values for a huge amount of chemicals,it is necessary to develop predictive *** this work,a quantitative structure-property relationship(QSPR)model for estimating log K_(lip/w)values of small organic compounds was constructed based on 305 experimental log K_(lip/w)*** chemical descriptors and n-octanol/water partitioning coefficient were employed to characterize the intermolecular interactions that dominate log K_(lip/w)*** hydrophobic and electrostatic interactions and molecular size have been found to play important roles in governing the distribution of chemicals between lipids and aqueous *** regression(R2=0.959)and validation(Q2=0.960)results indicate good fitting performance and robustness of the developed model.A comparison with the predictive performance of other commercial software further proves the higher accuracy and stronger predictive ability of the developed K_(lip/w)predictive ***,it can be used to predict the K_(lip/w)values of cycloalkanes,long-chain alkanes,halides(with fluorine,chlorine,and bromine as substituents),esters(without phosphate groups),alcohols(without methoxy groups),and aromatic compounds.

关键词： Storage lipid/water distribution coefficient log Klip/w Organic compounds QSPR Quantum chemical descriptors

Effectiveness of acupuncture-related therapies on schizophrenia:a Bayesian network Meta-analysis

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Journal of Traditional Chinese Medicine 2023年第2期43卷 239-251页

作者： HUANG Zhaohan FANG yuan WANG xiaolu han yue yu Qi WANG Tong School of Traditional Chinese Medicine Beijing University of Chinese MedicineInstitute of traditional Chinese medicineBeijing 102488China Maternal and women’s health department Shanghai Center for Women and Children’s HealthShanghai 200062China

OBJECTIVE:To create the hierarchical model for the comparison of efficacy of different ATs for ***:PubM ed,Web of Science,Embase,The Cochrane Library,ClinicalTrials,China National Knowledge Infrastructure Database,China Science and Technology Journal Database,Wanfang Database,and SinoM ed were searched using a specified search strategy to identify relevant studies up to December *** data were extracted independently by two *** quality of included trials was evaluated based on the guidelines of“Cochrane handbook for Systematic Reviews of Interventions”.Bayesian network metaanalysis was conducted by statistical analysis software Addis 1.16.6 and Stata ***:In total,60 randomized controlled trials covering 4810 patients were *** network metaanalysis result showed that Body Acupuncture(BA),BA+Electro-acupuncture(EA),Scalp Acupuncture(SA)+EA,Auricular Acupuncture(AA),Low-dose medication and Acupuncture(LA),Acupoint Injection(AI),and Acupoint Catgut Embedding(ACE),when combined with Western Medications(WM),demonstrated a better clinical effect at improving the symptoms of schizophrenia,compared to WM *** of rank probability showed that BA,when combined with WM,was the most optimal AT for schizophrenia at decreasing three aspects of PANSS scale ***:Acupuncture-related therapies help improve the symptoms of schizophrenia,and BA combined with WM may be a better therapy for schizophrenia.

关键词： Schizophrenia Acupuncture Acupuncture-related therapy Network Meta-analysis

豫西黄土高原果园生草对土壤线虫群落及结构的影响

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草地学报 2024年第1期32卷 96-104页

作者：包涵吕丹丹施赟贺雨轩赵金梦许革学李晓敏王冬河南大学生命科学学院河南开封475004 河南省灵宝市特色农业发展中心河南三门峡472500

土壤线虫是土壤生物中最丰富的后生动物,从线虫群落结构角度评价果园不同覆盖作物的土壤质量可为果园管理提供依据。2022年在黄土高原东部果园开展实验,供试品种为‘富士’苹果(Malus domestica cv. Fuji),处理包括:农田、单播毛苕子(Vi... 详细信息

土壤线虫是土壤生物中最丰富的后生动物,从线虫群落结构角度评价果园不同覆盖作物的土壤质量可为果园管理提供依据。2022年在黄土高原东部果园开展实验,供试品种为‘富士’苹果(Malus domestica cv. Fuji),处理包括:农田、单播毛苕子(Vicia sativa L.)、单播黑麦草(Lolium perenne L.)。与农田对照相比,覆盖毛苕子线虫总丰度及食细菌线虫相对丰度分别显著提高了302.33%和38.41%,植物寄生线虫与杂食和捕食线虫的相对丰度分别降低了62.18%和86.12%。覆盖黑麦草较对照处理导致杂食和捕食线虫的相对丰度降低了55.59%。土壤微生物碳含量、变形菌门相对丰度、土壤pH值、豆科生物量比例是影响线虫群落结构的主要因子。果园行间覆盖毛苕子可优化线虫群落结构,有利于果树根系的生长,建议豫西黄土高原果园生草选择豆科物种毛苕子为益。

关键词：黄土高原苹果园土壤线虫覆盖作物土壤微生物