检索结果-南通市图书馆

The effect of hydrogen on the electronic structure of kink in bcc iron

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2009年第5期52卷 1212-1218页

作者： chen liqun1,QIU Zhengchen1,yu tao2 & wang chongyu2,3,4 1 college of sciences,central south university of forestry and technology,changsha 410004,china 2 central Iron and Steel Research Institute,Beijing 100081,china 3 Department of Physics,Tsinghua university,Beijing 100084,china 4 International Center for Materials Physics,Chinese Academy of sciences,Shenyang 110016,china 1. college of sciences Central South University of Forestry and Technology Changsha 410004 China 2. central Iron and Steel Research Institute Beijing 100081 China 3. Department of Physics Tsinghua University Beijing 100084 China 4. International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

The electronic structures of kinks in the [100](010) and 1/2[111](-110) edge dislocations in bcc iron containing hydrogen are investigated by means of the first-principles DMol method and the discrete variational *** effects of hydrogen on the kinks are *** results show that hydro-gen forms weak bonding states with its neighboring host atoms,and since hydrogen draws charge from its neighboring host atoms,the interactions between most of the host atoms are weakened com-pared with those of the corresponding atomic pairs in the clean *** indicates that the migration of kink,*** motion of dislocation,is easier in the doping hydrogen kink than in the clean kink,which may be the solid solution softening effect resulting from the impurity hydrogen.

关键词： electronic structure dislocation kink impurity

First-principles investigation of the impurity-kink interaction in bcc iron

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第12期53卷 1796-1803页

作者： yu tao chen liqun wang chongyu QIU Zhengchen DU JunPing central Iron and Steel Research Institute Beijing 100081 China college of sciences Central South University of Forestry and Technology Changsha 410004 China Department of Physics Tsinghua University Beijing 10084 China

Using the first-principles self-consistent discrete variational method based on density functional theory, we investigated the effect of light impurities C and N on the electronic structure of kink on the [100](010) edge dislocation (ED) in bcc iron. Our energetic calculations show that the light impurities have a strong segregation tendency to enter the kink. The results of the charge distribution and the local den-sity of states indicate that the strong bonds between the impurity atoms and the neighboring Fe atoms are formed due to the hybridizations of impurity atoms 2p states and Fe 3d4s4p states. The introduction of light impurities can stabilize the kink system, and impedes the sideward motion of the kink in the [100](010) ED. This is, the light impurities induce a strong pinning effect on the [100](010) ED and may result in the solid solute hardening.

关键词：电子结构交互作用杂质密度泛函理论铁

三聚氰胺改性对木质素酚醛树脂胶合性能的影响

在线全文

学校读者我要写书评

暂无评论

中南林业科技大学学报 2024年第1期44卷 194-201页

作者：沈隽何先楠王国霖陈宇东北林业大学材料科学与工程学院黑龙江哈尔滨150040

【目的】通过三聚氰胺对木质素酚醛树脂(LPF)改性,提高LPF的胶合性能,降低固化温度,为人造板的绿色生产和节能降耗提供新思路。【方法】对比三聚氰胺与(苯酚+木质素)、三聚氰胺/(苯酚+木质素)与甲醛不同摩尔比对三聚氰胺改性木质素酚醛... 详细信息

【目的】通过三聚氰胺对木质素酚醛树脂(LPF)改性,提高LPF的胶合性能,降低固化温度,为人造板的绿色生产和节能降耗提供新思路。【方法】对比三聚氰胺与(苯酚+木质素)、三聚氰胺/(苯酚+木质素)与甲醛不同摩尔比对三聚氰胺改性木质素酚醛树脂(MLPF)的性能影响,得到MLPF的最佳合成条件。并与相同酚醛比和木质素取代率的酚醛树脂(PF)和LPF进行性能对比,利用FTIR和DSC对PF、LPF和MLPF的结构和固化温度进行比较分析。【结果】当三聚氰胺与(苯酚+木质素)的摩尔比为4∶6、三聚氰胺/(苯酚+木质素)与甲醛的摩尔比为1∶2时,MLPF的凝胶时间最短,为318.62 s,所压制的MLPF胶合板干、湿胶合强度为2.04和1.43 MPa,甲醛释放量为0.088 mg/m^(3),且与PF和LPF胶合板相比MLPF的胶合强度更高,满足GB/T14732—2017和GB/T 9846—2015国家标准性能要求。FTIR结果显示,相较于PF和LPF,MLPF在3 327 cm^(-1)和3 214 cm^(-1)处拥有属于-OH和-N-H的双峰,在1 079 cm^(-1)和1 036 cm^(-1)处出现的N-C-N特征峰以及在809 cm^(-1)处属于三嗪环面外震动的吸收峰,都证明了三聚氰胺经过羟甲基化并参与到MLPF的合成中。DSC结果显示,经过三聚氰胺改性后的MLPF放热峰值温度出现在140℃,其固化温度相较于LPF和PF分别降低了17.16%和22.22%。【结论】三聚氰胺的加入使得MLPF的凝胶时间更短,固化温度更低,MLPF胶合板的性能相较于LPF无论是胶合强度还是耐水性均有明显提升。

关键词：三聚氰胺木质素酚醛树脂胶合强度凝胶时间固化温度

在线全文

学校读者我要写书评

暂无评论

贵州枇杷种质资源分布及其产业发展概述

果树学报 2024年第2期41卷 338-352页

作者：杨勇胜王道静陈阳松范付华魏椿余桃江旭升李庆宏李斌陈树红贵阳市农业试验中心贵阳550018 贵州大学林学院贵阳550025

贵州立体气候突出,野生枇杷种质资源丰富,性状差异性明显。目前已找到普通枇杷、大花枇杷、小叶枇杷3个种类,普通枇杷在全省广泛分布,大花枇杷主要分布在黔东南州雷公山一带,小叶枇杷主要分布在黔西南州兴义市一带。贵州省枇杷商品化栽... 详细信息

贵州立体气候突出,野生枇杷种质资源丰富,性状差异性明显。目前已找到普通枇杷、大花枇杷、小叶枇杷3个种类,普通枇杷在全省广泛分布,大花枇杷主要分布在黔东南州雷公山一带,小叶枇杷主要分布在黔西南州兴义市一带。贵州省枇杷商品化栽培始于1958年,由黔东南州率先从江苏、浙江、福建等省引进优良品种进行试验示范。进入20世纪80年代中后期,贵阳市、黔南州、黔西南州等各地州(市)相继开展引种试验及小规模推广应用。截至2010年,在贵阳市、黔东南州、毕节市等地区拥有了万亩以上的规模化种植。特别是2015年以来,贵州各地枇杷种植生产发展速度迅猛,据2022年贵州省农业农村厅统计数据,全省枇杷种植面积已达2.3万hm^(2),年产量16.3万t,产值达17.1亿元,鲜果采摘期超过2个月。但栽培技术与管理水平仍较低,面积上升与产量增长不成正比,全省平均每666.7 m^(2)商品果产量不足500 kg,提升空间很大。存在问题主要为,一是缺乏地方规范的引、试、推制度体系,盲目性引种,造成品种混杂,良莠不齐,商品性低;二是对遗传优良性状的种质资源挖掘不足,缺乏地方特色的主导品种,市场竞争力不强;三是枇杷品牌创建与营销策略意识不强,形成行业内竞争压价销售,影响效益;四是鲜果产后冷链及深加工产品技术研发滞后,产业附加值增长有限;五是旱涝寒暑等极端天气频繁出现,山地果园设施栽培配套条件滞后,抗风险能力不强等。主要围绕贵州枇杷种质资源分布特征、引种与育种、栽培技术演变、产业发展及其制约因子等方面进行了分析,尝试提出贵州枇杷产业当前与未来的主要任务,以推动枇杷产业高质量发展。

关键词：枇杷贵州种质资源分布产业

Emerging contaminants:A One Health perspective

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

The Innovation 2024年第4期5卷 140-170,139页

作者： Fang wang Leilei Xiang Kelvin Sze-Yin Leung Martin Elsner Ying Zhang yuming Guo Bo Pan Hongwen Sun Taicheng An Guangguo Ying Bryan WBrooks Deyi Hou Damian EHelbling Jianqiang Sun Hao Qiu Timothy MVogel Wei Zhang Yanzheng Gao Myrna JSimpson Yi Luo Scott XChang Guanyong Su Bryan MWong Tzung-May Fu Dong Zhu Karl JJobst chengjun Ge Frederic Coulon Jean Damascene Harindintwali Xiankui Zeng Haijun wang yuhao Fu Zhong Wei Rainer Lohmann Changer chen Yang Song Concepcion Sanchez-Cid yu wang Ali El-Naggar Yiming Yao Yanran Huang Japhet Cheuk-Fung Law chenggang Gu Huizhong Shen Yanpeng Gao Chao Qin Hao Li Tong Zhang Natàlia Corcoll Min Liu Daniel SAlessi Hui Li Kristian KBrandt Yolanda Pico cheng Gu Jianhua Guo Jianqiang Su Philippe Corvini Mao Ye Teresa Rocha-Santos Huan He Yi Yang Meiping Tong Weina Zhang Fidèle Suanon Ferdi Brahushi Zhenyu wang Syed AHashsham Marko Virta Qingbin yuan Gaofei Jiang Louis A.Tremblay Qingwei Bu Jichun Wu Willie Peijnenburg Edward Topp Xinde Cao Xin Jiang Minghui Zheng taolin Zhang Yongming Luo Lizhong Zhu Xiangdong Li DamiàBarceló Jianmin chen Baoshan Xing Wulf Amelung Zongwei Cai Ravi Naidu Qirong Shen Janusz Pawliszyn Yong-guan Zhu Andreas Schaeffer Matthias C.Rillig Fengchang Wu Gang yu James M.Tiedje State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China university of Chinese Academy of sciences Beijing 100049China Department of Chemistry Hong Kong Baptist UniversityHong KongChina HKBU Institute of Research and Continuing Education Shenzhen Virtual University ParkShenzhenChina Technical university of Munich TUM School of Natural SciencesInstitute of Hydrochemistry85748 GarchingGermany School of Resources&Environment Northeast Agricultural UniversityHarbin 150030China Climate Air Quality Research UnitSchool of Public Health and Preventive MedicineMonash UniversityMelbourneVICAustralia Faculty of Environmental Science&Engineering Kunming University of Science&TechnologyKunming 650500China Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control School of Environmental Science and EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Ministry of Education Key Laboratory of Environmental Theoretical Chemistry South China Normal UniversityGuangzhouGuangdong 510006China Department of Environmental Science Baylor UniversityWacoTXUSA Center for Reservoir and Aquatic Systems Research(CRASR) Baylor UniversityWacoTXUSA School of Environment Tsinghua UniversityBeijing 100084China School of Civil and Environmental Engineering Cornell UniversityIthacaNY 14853USA Key Laboratory of Microbial technology for Industrial Pollution Control of Zhejiang Province Zhejiang University of TechnologyHangzhou 310014China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Laboratoire d’Ecologie Microbienne Universite Claude Bernard Lyon 1UMR CNRS 5557UMR INRAE 1418VetAgro Sup69622 VilleurbanneFrance Department of Pla

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary *** global efforts to mitigate legacy pollutants,the continuous introduction of new substances remains a major threat to both people and the *** response,global initiatives are focusing on risk assessment and regulation of emerging contaminants,as demonstrated by the ongoing efforts to establish the UN’s Intergovernmental Science-Policy Panel on Chemicals,Waste,and Pollution *** review identifies the sources and impacts of emerging contaminants on planetary health,emphasizing the importance of adopting a One Health *** for monitoring and addressing these pollutants are discussed,underscoring the need for robust and socially equitable environmental policies at both regional and international *** actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.

关键词： pollution planet contaminants

枯草芽孢杆菌PW2挥发性产物对黄曲霉的抑制作用

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

食品与生物技术学报 2024年第5期43卷 122-129页

作者：张凯歌魏琛余璐杜明艳李晓冉林亲录王青云中南林业科技大学食品科学与工程学院湖南长沙410004 中南林业科技大学稻谷及副产物深加工国家工程研究中心湖南长沙410004

为探寻安全、高效的黄曲霉新型抑制物,采用顶空固相微萃取-气质联用(HS-SPME-GC-MS)技术对枯草芽孢杆菌(Bacillus subtilis)PW2所产具有抗霉活性的挥发性有机化合物(volatile organic compounds,VOCs)进行了成分鉴定,并利用平板对扣法... 详细信息

为探寻安全、高效的黄曲霉新型抑制物,采用顶空固相微萃取-气质联用(HS-SPME-GC-MS)技术对枯草芽孢杆菌(Bacillus subtilis)PW2所产具有抗霉活性的挥发性有机化合物(volatile organic compounds,VOCs)进行了成分鉴定,并利用平板对扣法从鉴定出的成分中筛选具有强抗霉活性的目标化合物,通过平板对扣法和96孔板梯度稀释法测定目标化合物对黄曲霉的最小抑菌体积分数(MIC),使用黄曲霉毒素B_(1)(aflatoxin B_(1),AFB_(1))ELISA检测试剂盒分析了目标化合物对黄曲霉产AFB_(1)的抑制作用,使用扫描电子显微镜(scanning electron microscope,SEM)观察受试黄曲霉孢子形态的变化和采用分光光度法测定受试黄曲霉细胞膜麦角甾醇相对含量,以探讨抗霉机理。结果显示,从PW2所产VOCs中共鉴定出41种组分,并从中筛选出异辛醇为目标化合物;平板对扣法和96孔板梯度稀释法测得异辛醇对黄曲霉的MIC分别为0.169μL/mL和6.25μL/mL;PDB培养基中异辛醇体积分数分别为3.13、6.25、12.50μL/mL时,均能有效抑制AFB_(1)的产生,且随异辛醇体积分数的升高,抑制效果增强;异辛醇处理可导致黄曲霉孢子表面凹陷和孢子破裂,并且影响细胞膜中麦角甾醇的相对含量,造成细胞膜受损。该研究可为开发以异辛醇为功能成分的黄曲霉抑制剂提供理论参考。

关键词：枯草芽孢杆菌挥发性有机化合物异辛醇黄曲霉

Bimetallic chalcogenides for electrocatalytic CO_(2)reduction

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2021年第12期40卷 3442-3453页

作者： Qian Li yu-Chao wang Jian Zeng Xin Zhao chen chen Qiu-Mei Wu Li-Miao chen Zhi-Yan chen Yong-Peng Lei School of Material Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Powder Metallurgy Hunan Key Laboratory of Two-Dimensional MaterialsCentral South UniversityChangsha 410083China Energy Materials Computing Center Jiangxi University of Science and TechnologyNanchang 330013China Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China

Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)converts CO_(2)into valuable chemical fuels,which can effectively alleviate global warming and energy ***,limited by its slow reaction rate and low product selectivity,it is urgent to design efficient,cheap,safe,and highly selective CO_(2)RR *** to the advantages of adjustable electronic structure,abundant active sites,low cost,environmental friendliness and excellent electrochemical performance,bimetallic chalcogenides have aroused great ***,we briefly summarized different bimetallic oxides and sulfides for electrocatalytic CO_(2)RR in the past five *** addition,different hybridizations formed between metal atoms,including intermetallic compounds,heterostructures and metal doping,were *** positive effects on CO_(2)RR catalytic selectivity and activity were deeply ***,we also put forward some views about the future research directions and perspectives in CO_(2)RR *** review aims to provide a reference for the rational design of bimetallic chalcogenides towards electrocatalytic CO_(2)reduction.

关键词： Electrocatalysis CO_(2)reduction Bimetallic chalcogenides Electronic structure

Genome size evolution of the extant lycophytes and ferns

在线全文

学校读者我要写书评

暂无评论

Plant Diversity 2022年第2期44卷 141-152页

作者： Fa-Guo wang Ai-Hua wang cheng-Ke Bai Dong-Mei Jin Li-yun Nie AJ Harris Le Che Juan-Juanwang Shi-yu Li Lei Xu Hui Shen yu-Feng Gu Hui Shang Lei Duan Xian-Chun Zhang Hong-Feng chen yue-Hong Yan Key Laboratory of Plant Resources Conservation and Sustainable Utilization Guangdong Provincial Key Laboratory of Applied BotanySouth China Botanical GardenChinese Academy of SciencesGuangzhou510650China college of Life sciences Shaanxi Normal UniversityXi'an710062China Eastern china Conservation Centre for Wild Endangered Plant Resources Shanghai Chenshan Botanical GardenShanghai201602China Key Laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning530001China Department of Biology Oberlin CollegeOberlinOH44074USA State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing100093China Key Laboratory of National forestry and Grassland Administration for Orchid Conservation and Utilization the National Orchid Conservation Center of China and the Orchid Conservation&Research Center of Shenzhen518114ShenzhenChina Life Science and technology college Harbin Normal UniversityHarbin150025China

Ferns and lycophytes have remarkably large ***,little is known about how their genome size evolved in fern *** explore the origins and evolution of chromosome numbers and genome size in ferns,we used flow cytometry to measure the genomes of 240 species(255 samples)of extant ferns and lycophytes comprising 27 families and 72 genera,of which 228 species(242 samples)represent new *** analyzed correlations among genome size,spore size,chromosomal features,phylogeny,and habitat type preference within a phylogenetic *** also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome *** the phylogeny,we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat *** found that 2 C values had weak phylogenetic signal,whereas the base number of chromosomes(x)had a strong phylogenetic ***,our analyses revealed a positive correlation between genome size and chromosome traits,indicating that the base number of chromosomes(x),chromosome size,and polyploidization may be primary contributors to genome expansion in ferns and *** sizes in different habitat types varied significantly and were significantly correlated with habitat types;specifically,multinomial logistic regression indicated that species with larger 2 C values were more likely to be *** habitat is inferred to be ancestral for both extant ferns and lycophytes,whereas transitions to other habitat types occurred as the major clades *** in habitat types appear be followed by periods of genomic *** on these results,we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.

关键词： Genome size Ferns Chromosome numbers Habitat type Whole-genome duplications Evolution

Population and conservation status of a transboundary group of black snub-nosed monkeys(Rhinopithecus strykeri)between china and Myanmar

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2022年第4期43卷 523-527页

作者： Yi-Xin chen Yang yu cheng Li Zhi-Shu Xiao Guo-Wei Zhou Zhong-Jian Zhang Xin-Wen wang Zuo-Fu Xiang Jiang Chang Ming Li Institute of Evolutionary Ecology and Conservation Biology Central South University of Forestry&TechnologyChangshaHunan 410004China college of Life Science and technology Central South University of Forestry&TechnologyChangshaHunan 410004China State Key Lab of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Lushui Bureau of Mt.Gaoligong National Nature Reserve LiukuYunnan 673229China college of forestry Central South University of Forestry&TechnologyChangshaHunan 410004China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Key Lab of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China

DEAR EDITOR,We examined the distribution,population,and conservation status of the critically endangered Myanmar or black snub-nosed monkey(Rhinopithecus strykeri)via field surveys over 26 months(2019-2021)in the Pianma region of the china-Myanmar *** to previous reports,we only identified one group in the region,which was a cross-border group occupying a multi-year home range of 51.50-57.02 km^(2).The current group size was much larger(155-160 individuals)than that in 2012-2014(ca 100 individuals),and the group appeared to be ***,confirmed poaching,mining,and transboundary forest fires on the Myanmar side of the border threaten their survival.

关键词： black boundary Myanmar