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Anisotropic electrical properties of aligned PtSe_(2) nanoribbon arrays grown by a pre-patterned selective selenization process

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Nano Research 2022年第5期15卷 4668-4676页

作者： Huaipeng Wang Zhifang Liu Yilin Sun xiaofan ping Jianlong Xu Yingtao Ding Haowen Hu Dan Xie Tianling Ren School of Integrated Circuits Beijing National Research Center for Information Science and Technology(BNRist)Tsinghua UniversityBeijing 100084China Department of Chemistry Tsinghua UniversityBeijing 100084China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

This study proposes a feasible and scalable production strategy to naturally obtain aligned platinum diselenide(PtSe_(2))nanoribbon arrays with anisotropic *** anisotropic properties of two-dimensional(2D)materials,especially transition-metal dichalcogenides(TMDs),have attracted great interest in *** dependence of physical properties on their lattice orientations is of particular interest because of its potential in diverse applications,such as nanoelectronics and ***-dimensional(1D)nanostructures facilitate many feasible production strategies for shaping 2D materials into unidirectional 1D nanostructures,providing methods to investigate the anisotropic properties of 2D materials based on their lattice orientations and *** natural alignment of zigzag(ZZ)PtSe_(2) nanoribbons is experimentally demonstrated using angle-resolved polarized Raman spectroscopy(ARPRS),and the selective growth mechanism is further theoretically revealed by comparing edges and edge energies of different orientations using the density functional theory(DFT).Back-gate field-effect transistors(FETs)are also constructed of unidirectional PtSe_(2) nanoribbons to investigate their anisotropic electrical properties,which align with the results of the projected density of states(DOS)*** work provides new insight into the anisotropic properties of 2D materials and a feasible investigation strategy from experimental and theoretical perspectives.

关键词： PtSe_(2) scalable production anisotropic properties nanoribbons density functional theory

On the Occurrence Time of an Earthquake Cluster in the Shanxi Reservoir

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Earthquake Research in China 2006年第4期20卷 406-411页

作者： Niu Anfu Zhang Xiaodong Zheng Dalin Li xiaofan Ji ping China Earthquake Networks Center CEABeijing 100036 China

An earthquake cluster occurred in the Shanxi reservoir, located around Wenzhou city in Zbejiang Province. From February 4 to February 11, 2006, 9 earthquakes with ML ≥ 4.0 occurred, and the greatest magnitude was ML4.6. The correlations of earthquake occurrence time with reservoir level changes and tides are discussed, and the possible factors that induced the reservoir earthquakes and the trend of seismic activity are analyzed based on the characteristics of earthquake occurrence time. Finally, we suggest that it is necessary to slow down the speed of storing water and to maintain a level below the highest historical level to avoid greater earthquakes in the reservoir.

关键词： Shanxi reservoir Water level Earthquake cluster Solid tide

原子转移自由基聚合反应改性氧化石墨烯研究进展

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高分子材料科学与工程 2017年第2期33卷 184-190页

作者：王丽芳平小凡孙恺陈晴潘凯北京化工大学材料科学与工程学院碳纤维及功能高分子教育部重点实验室北京100029

原子转移自由基聚合(ATRP)是一种具有潜在应用价值的可控活性自由基聚合方法,通过ATRP反应对氧化石墨烯(GO)进行改性,可以有效控制各种接枝聚合物分子链的长度和接枝密度,赋予GO不同的功能性,如良好的溶剂分散性、环境敏感刺激响应性、... 详细信息

原子转移自由基聚合(ATRP)是一种具有潜在应用价值的可控活性自由基聚合方法,通过ATRP反应对氧化石墨烯(GO)进行改性,可以有效控制各种接枝聚合物分子链的长度和接枝密度,赋予GO不同的功能性,如良好的溶剂分散性、环境敏感刺激响应性、生物相容性等。文中分别从GO表面固定引发剂直接引发ATRP反应和GO表面非共价键结合ATRP聚合物分子链2种途径,对ATRP反应改性GO进行综述,总结了ATRP改性反应的过程条件和研究方法,并指出了GO功能化复合材料的功能特性和应用前景。

关键词：原子转移自由基聚合氧化石墨烯改性

A Computational Study On The Mechanism Of The Cyanosilylation Of Ketones Catalyzed By 1,1,3,3-tetramethylguanidine Without Solvent

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A Computational Study On The Mechanism Of The Cyanosilylatio...

A Density Functional Study on the Effect of Acidic and Alkali Medium on Molecular Structures of Cryptotanshinone and Tanshinone Ⅰ

第九届全国计算（机）化学学术会议

作者： xiaofan ping Yong Guo Daiqian Xie Ying Xue Xiaoming Feng College of Chemistry,Sichuan University

The mechanism of cyanosilylation of ketones catalyzed by 1,1,3,3-tetramethylguanidine (TMG)was investigated using the density functional theory(DFT)at the B3LYP/6-31G level.

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A Density Functional Study on the Effect of Acidic and Alkal...

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

第九届全国计算（机）化学学术会议

作者： xiaofan ping Yong Guo Ying Xue Daiqian Xie Guosen Yan College of Chemistry,Sichuan University,Chengdu 610064,P.R.China

The effect of acidic and alklic medium on the molecular structures of Cryptotanshinone (Ctan)and Tanshinone I(Tan Ⅰ)have been investigated by using DFT/B3LYP method with the standard 6-31+Gor 6-31G basis *** is characterized by the presence of a dihydrofuran or furan ring and o-quinone moiety,which are mainly active *** or furan ring and quinine are able to react with nuclephilic agents which widely lie in biological bodies,for example,hydroninm *** may relate to the anti-bacterial and anti-inflammatory function of tanshinones. Some studies suggested the structure-activity relationship among these tanshinones,and some one think the activity not only depend on structure,but also on the environmental factors of the compounds,for example,acidic and alkali *** results reveald that under acidic condition,the conjugation systems of tanshinone molecules were destroyed,but the structures of tanshinones were not changed;under alkali condition,the furan or dihydrofuran ring of tanshinone molecules can be opened,and the dihydrofuran ring-opening was reversible,the furan ring-opening was *** were agreement with the experimental results,but our relevant reaction mechanisms showed that the addition reaction of nucleophilic agent was not in cooperation with the reaction of the ring-opening,they were stepwise,the addition intermediation were stable.

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG ping GUAN Chi ZHANG Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

山新杨谷胱甘肽S-转移酶PdbGST基因的克隆与胁迫表达分析

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林业科技 2024年第3期49卷 33-40页

作者：平晓帆遇文婧黄颖黑龙江省森林保护研究所黑龙江哈尔滨150081

在植物中,谷胱甘肽S-转移酶是一类多功能酶,能够在其响应非生物胁迫中发挥作用。为研究该基因在杨树中的功能,本研究克隆了山新杨谷胱甘肽S-转移酶基因Pdb GST及其启动子序列,对其进行生物信息学分析和表达特征分析。结果显示,Pdb GST... 详细信息

在植物中,谷胱甘肽S-转移酶是一类多功能酶,能够在其响应非生物胁迫中发挥作用。为研究该基因在杨树中的功能,本研究克隆了山新杨谷胱甘肽S-转移酶基因Pdb GST及其启动子序列,对其进行生物信息学分析和表达特征分析。结果显示,Pdb GST基因的开放阅读框(ORF)全长666 bp,编码221个氨基酸,其形成的蛋白质相对分子质量为25.57 k Da,为稳定亲水性酸性蛋白,定位于细胞质中。系统进化分析表明,山新杨Pdb GST蛋白与山新杨中的XP_034926648蛋白的同源性最高。对克隆获取的2 000 bp启动子序列进行分析,结构显示该启动子序列中,含有多种响应非生物胁迫的顺式作用元件。荧光定量PCR分析显示Pdb GST基因在山新杨根部表达量最高,其次在山新杨叶部也有较高表达量,相反在山新杨顶芽中表达量最低。此外,对Pdb GST基因响应非生物胁迫分析显示,山新杨根部Pdb GST基因受诱导后即出现持续且大量的表达。

关键词：山新杨谷胱甘肽S-转移酶非生物胁迫表达模式

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遮荫对引种玉簪生长及光合特性的影响

森林工程 2018年第5期34卷 20-26页

作者：平晓帆遇文婧宋小双黑龙江省森林保护研究所哈尔滨150040

通过研究不同光照强度对引种玉簪(Hosta)的生长及光合作用的影响,为不同品种玉簪进行园林配置提供必要的理论依据。对初期筛选获得的3种引种玉簪及对照东北玉簪进行不同遮阴处理,通过测定株高、生物量以及净光合速率(Pn)、气孔导度(Cond... 详细信息

通过研究不同光照强度对引种玉簪(Hosta)的生长及光合作用的影响,为不同品种玉簪进行园林配置提供必要的理论依据。对初期筛选获得的3种引种玉簪及对照东北玉簪进行不同遮阴处理,通过测定株高、生物量以及净光合速率(Pn)、气孔导度(Cond)、胞间CO2浓度(Ci)和蒸腾速率(Tr)的日变化,分析不同遮阴处理条件下引种玉簪的生长特性和光合特性。结果表明:不同遮光处理下,S25组的3种引种玉簪和东北玉簪的株高变化不显著,而S50和S75组中玉簪T和F的株高显著降低,玉簪S与东北玉簪无显著变化;除玉簪S和东北玉簪外,其他玉簪的根部组织干重随着遮光度的增加而降低。3种引种玉簪和东北玉簪的净光合速率、气孔导度、胞间CO2浓度和蒸腾速率变化趋势一致;S25组的玉簪S在12:00时的净光合速率显著增加,高于S0组30.5%;玉簪F和玉簪S的气孔导度在不同遮阴组中的峰值均显著高于无遮阴S0组;S75组中玉簪F的胞间CO2浓度在16:00时显著增加,高于无遮阴S0组16.39%;遮阴后的玉簪T和F的蒸腾速率在12:00时显著升高,玉簪S的蒸腾速率在不同时间点均显著升高。因此,玉簪S在较强的遮阴条件下生长较旺盛,光合作用较强。

关键词：玉簪耐阴性生长特性光合特性引种

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便携式森林扑火长把切割机

林业勘查设计 2019年第4期48卷 42-44,54页

作者：靳松平晓帆赵南黑龙江省森林保护研究所

便携式森林扑火长把切割机是针对森林扑火队员在开设防火隔离带和火场清理时,主要依靠手工工具的特殊情况而研制的,它是以内燃机为动力来源的手持式机械化森林扑灭火机具。

关键词：森林防火防火隔离带火场清理