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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU jian-Qiang MA zhao-Peng CHENG Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Fractionation and solubility of cadmium in paddy soils amended with porous hydrated calcium silicate

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Journal of Environmental Sciences 2007年第3期19卷 343-347页

作者： zhao xiu-lan Saigusa Masaihiko College of Natural Resources and Environmental Sciences Southwest University Chongqing 400716 China Experimental Farm Graduate School of Agricultural Sciences Tohoku University Naruko Miyagi 989-6711 Japan

Previous studies have shown that porous hydrated calcium silicate （PS） is very effective in decreasing cadmium （Cd） content in brown rice. However, it is unclear whether the PS influences cadmium transformation in soil. The present study examined the effect of PS on pH, cadmium transformation and cadmium solubility in Andosol and Alluvial soil, and also compared its effects with CaCO3, acidic porous hydrated calcium silicate （APS） and silica gel. Soil cadmium was operationally fractionationed into exchangeable （Exch）, bound to carbonates （Carb）, bound to iron and manganese oxides （FeMnOx）, bound to organic matters （OM） and residual （Res） fraction. Application of PS and CaCO3 at hig rates enhanced soil pH, while APS and silica gel did not obviously change soil pH. PS and CaCO3 also increased the FeMnOx-Cd in Andosol and Carb-Cd in Alluvial soil, thus reducing the Exch-Cd in the tested soils. However, PS was less effective than CaCO3 at the same application rate. Cadmium fractions in the two soils were not changed by the treatments of APS and silica gel. There were no obvious differences in the solubility of cadmium in soils treated with PS, APS, silica gel and CaCO3 except Andosol treated 2.0% CaCO3 at the same pH of soil-CaC12 suspensions. These findings suggested that the decrease of cadmium availability in soil was mainly attributed to the increase of soil pH caused by PS.

关键词： porous hydrated calcium silicate solubility soil cadmium

Effect of Pressure on the Nucleation of Diamond with Addition of Oxygen in the Microwave Plasma Chemical Vapor Deposition System

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Chinese Physics Letters 1996年第6期13卷 473-476页

作者： WANG jian-jun LÜFan-xiu Department of Materials Science and Engineering Beijing University of Science and TechnologyBeijing 100083

Effect of oxygen addition on diamond film deposition at higher pressure was *** was found that addition of oxygen suppressed diamond nucleation,and the effect of suppression increased with increasing pressure,and at certain pressure level diamond deposition was completely *** effect due to oxygen addition dominated at the very early stage(nucleation stage),therefore it is still possible to take the advantage of oxygen addition on quality improvement of diamond films by introducing oxygen after the nucleation stage.

关键词： Diamond Oxygen effect

Current knowledge on the multiform reconstitution of intestinal stem cell niche

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World Journal of Stem Cells 2021年第10期13卷 1564-1579页

作者： Zi-Yan Xu Jin-jian Huang Ye Liu Yun zhao xiu-Wen Wu jian-An Ren Research Institute of General Surgery Jinling HospitalMedical School of Nanjing UniversityNanjing 210002Jiangsu ProvinceChina Medical School Southeast UniversityNanjing 210009Jiangsu ProvinceChina Department of General Surgery BenQ Medical CenterNanjing 210019Jiangsu ProvinceChina

The development of“mini-guts”organoid originates from the identification of Lgr5+intestinal stem cells(ISCs)and circumambient signalings within their specific niche at the crypt *** in vitro self-renewing“mini-guts”,also named enteroids or colonoids,undergo perpetual proliferation and regulated differentiation,which results in a high-performance,self-assembling and physiological organoid platform in diverse areas of intestinal research and *** triumphant reconstitution of ISC niche in vitro also relies on Matrigel,a heterogeneous sarcoma *** the promising prospect of organoids research,their expanding applications are hampered by the canonical culture pattern,which reveals limitations such as inaccessible lumen,confine scale,batch to batch variation and low *** tumor-origin of Matrigel also raises biosafety concerns in clinical ***,the convergence of breakthroughs in cellular biology and bioengineering contribute to multiform reconstitution of the ISC ***,we review the recent advances in the microfabrication of intestinal organoids on hydrogel systems.

关键词： Intestinal organoids Reconstitution Stem cell niche Bioengineering Hydrogel

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Finite NPDM-groups

Acta Mathematica Sinica,English Series 2021年第2期37卷 306-314页

作者： jian Ji CAO xiu Yun GUO School of Applied Mathematics Shanxi University of Finance and EconomicsTaiyuan 030006P.R.China Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

In this paper the classification is given for finite groups in which the normalizer of every non-normal cyclic subgroup of order divided by the minimal prime of |G| is a maximal subgroup.

关键词： Normalizer cyclic subgroup maximal subgroup

Development of real-time laser-scanning system to detect tree canopy characteristics for variable-rate pesticide application

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International Journal of Agricultural and Biological Engineering 2017年第6期10卷 155-163页

作者： Cai Jichen Wang xiu Song jian Wang Songlin Yang Shuo zhao Chunjiang College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China National Research Center of Intelligent Equipment for Agriculture Beijing 100097China Key Laboratory of Agri-informatics Ministry of AgricultureBeijing 100097China Beijing Key Laboratory of Intelligent Equipment Technology for Agriculture Beijing 100097China

Improving pesticide application efficiency is increasingly important in orchard *** this study,a laser-scanning system was designed to acquire gridding volumes of a tree to quantify the geometry characteristics of the tree canopy in real-time.A laser-scanning sensor mounted on a linear guide was utilized to measure the structure of a target tree canopy.A computer was used to receive measurement data from the laser scanner and obtain the movement distance of the laser-scanning sensor from a *** algorithm written with VC#program was designed to calculate gridding volumes of trees by recognizing valid measurement data from the laser *** evaluations were conducted on three kinds of regular objects,and the maximum relative errors of section volumes of the cuboid,triangular prism and cylinder objects were 3.3%,7.9%and 9.4%,respectively,which illustrated that the algorithm could calculate the section volumes in different parts of the objects with high accuracy.A conifer tree and an apple tree were chosen to verify detecting accuracy of the laser-scanning system at variable speeds and grid *** variation coefficients of total volumes for each kind of the tree were 0.078 and 0.041,respectively,which indicated that the laser-scanning system could be applied to provide the gridding volumes of different canopy densities in real-time with good reliability for guiding a variable-rate sprayer.

关键词： laser-scanning system sensor tree canopy variable-rate spray pesticide application efficiency gridding volumes calculation algorithm

Synthesis and Crystal Structure of [Cd(NBA)(μ_3-OH)(4,4′-bipy)_(1/2)]_n

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Chinese Journal of Structural Chemistry 2007年第8期26卷 917-919页

作者： SHEN Yi-Cheng ZHANG jian LI zhao-Ji ZHANG Lei YIN Pei-xiu YAO Yuan-Gen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A new cadmium polymer [Cd（NBA）（μ3-OH）（4,4＇-bipy）1/2]n 1 （NBA=m-nitrobenzoic acid and 4,4＇-bipy=4,4-bipyridine） has been synthesized by hydrothermal reaction. Its structure was determined by single-crystal X-ray diffraction method, and characterized by elemental analysis and IR spectrum. The crystal is of monoclinic, space group C2/c, with a=15.6912（9）, b=25.9394（15）, c=6.7332（4）A, β=114.7700（10）°, V=2488.4（3）A^3, C12H9CdN2O5, Mr=373.61, Z=8, Dc=1.995 g/cm^3,μ=1.776 mm^-1, F（000）=1464, R=0.0411 and wR=0.1128 for 2130 observed reflections （I 〉 2σ（I））.X-ray diffraction studies reveal that the compound features a layered structure, in which 4,4＇-bipy ligands bridge Z type of double chains [Cd（μ3-OH）]n and NBA ligands locate at the two sides of the layer. The π-π interactions between the benzene rings of NBA ligands of two adjacent layers lead to the 3D framework.

关键词： cadmium polymer 4 4'-bipyridine m-nitrobenzoic acid crystal structure

基于反应气混合物的ICP-MS/MS测定原油中的钒和镍

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光谱学与光谱分析 2025年第1期45卷 101-106页

作者：蔡松韬黄莹秀袁亮代宇宣莫垚坤黄建华湖南工学院材料科学与工程学院湖南衡阳421002 湖南省中医药研究院中药研究所湖南长沙410013

原油中金属元素钒和镍(V和Ni)的含量和比值可为深入了解原油的沉积环境特征和有机质类型发挥重要作用。在原油炼制过程中,V和Ni作为原油催化裂化过程中的有害金属元素,会降低催化剂的活性,严重时会导致催化剂中毒,会严重腐蚀设备,在精... 详细信息

原油中金属元素钒和镍(V和Ni)的含量和比值可为深入了解原油的沉积环境特征和有机质类型发挥重要作用。在原油炼制过程中,V和Ni作为原油催化裂化过程中的有害金属元素,会降低催化剂的活性,严重时会导致催化剂中毒,会严重腐蚀设备,在精炼之前必须对原油中的V和Ni进行脱除处理。V和Ni具有致突变性和致癌性,识别或监测原油中V和Ni进入环境的潜在危险变得越来越重要,对原油中V和Ni的含量进行高灵敏精准测定具有重要意义。采用电感耦合等离子体串联质谱(ICP-MS/MS)测定原油中V和Ni的新策略。原油样品经航空煤油简单稀释后直接采用ICP-MS/MS进行分析,针对V和Ni受到的质谱干扰,在MS/MS模式下,采用由NH_(3)/He(He为缓冲气)和H_(2)组成的反应气混合物(NH_(3)/He/H_(2))作为反应气,基于V^(+)与NH_(3)/He/H_(2)不发生反应,而V^(+)的干扰离子与NH_(3)/He/H_(2)发生反应,采用原位质量法消除干扰,选择V^(+)进行测定;基于Ni^(+)与NH_(3)/He/H_(2)发生反应,采用质量转移法消除干扰,选择无干扰团簇离子Ni(NH_(3))_(3)^(+)进行测定。通过与NH_(3)/He反应模式进行对比研究发现,对于V的测定,加入H_(2)为反应气能快速去除氩基离子的干扰,并能协同NH_(3)消除氧化物离子的干扰;对于Ni的测定,加入H_(2)为反应气能促进全氢加合物(-NH_(3))的形成,从而提高生成Ni(NH_(3))_(3)^(+)的产率。在NH_(3)/He/H_(2)反应模式下,V和Ni的背景等效浓度(BEC)更低,Ni的灵敏度更高,V和Ni的检出限(LOD)分别低至0.83和3.76 ng·kg^(-1),定量限(LOQ)分别为2.77和12.5 ng·kg^(-1)。通过分析标准参考物质NIST SRM 1634c并进行加标回收实验评价方法的准确度和精密度,结果显示,方法的测定结果与标准参考物质的认证值基本一致,V和Ni的加标回收率分别为97.7%和103%,相对标准偏差(RSD)分别为1.8%和1.9%。所建立的分析方法避免了繁琐的样品预处理过程,具有操作简单快速、灵敏度高、准确度和精密度好的特点,适用于原油中V和Ni的检测,能为原油深加工中V和Ni的脱除提供理论依据。

关键词：原油电感耦合等离子体串联质谱钒(V) 镍(Ni) 氨气/氦气/氢气(NH_(3)/He/H_(2))

Weak absorption test and defect analysis of optical coatings

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光学精密工程 2005年第4期13卷 430-434页

作者： HE Hong-bo LI Xia FAN Shu-hai zhao Yuan-an SHAO jian-da FAN Zheng-xiu Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

Surface thermal lensing technique was developed into a high-sensitive apparatus for weak absorption test and defect analysis of optical coatings. A continuous-wave 1 064 nm Nd:YAG laser and a He-Ne laser were employed as pump source and probe source, respectively. Low noise photoelectrical components and a lock-in amplifier were used for photo-thermal deformation signal detection. In order to improve sensitivity, the apparatus configuration was optimized by choosing appropriate parameters, including pump beam spot size, chopper frequency, detection distance, waist radius and position of probe beam. Coating samples were mounted on a x-y stage. Different procedures, such as single spot, linear scan and 2-dimension area scan, could be performed manually or automatically. Various optical coatings were prepared by both electron beam evaporation and ion beam sputtering deposition. High sensitivity was obtained and low to 1×10 -7 weak absorption was tested in low-loss coating samples. For the sensitivity extreme of the system, 1×10 -8 absorption was reason out to be measured by surface thermal lensing technique. Very small standard deviation was achieved for the reproducibility evaluation. Moreover, a spatial resolution of 25 micron was proved according to the area scan which traced out the profile of photo-thermal defects inside optical coatings. The system was employed in the analyses of optical absorption, absorption uniformity and defect characterization, and revealed the relationship between laser-induced damage and absorption of optical coatings.

关键词：光学涂覆技术吸收能力稳定性激光技术