原子、离子基态的确定及原子基态表

本文为快捷确定原子、离子基态提供了一种新的简便的计算方法 .据此给出的原子基态表 。

锂离子电池电极材料表界面结构的原子尺度表征

锂离子电池充放电过程中,锂离子的传输要穿过多种表面和界面,表界面的性质对电池的功率密度、能量密度、充放电效率、使用寿命、循环稳定性等具有重要的影响。表界面一般具有与体相不同的结构,在原子尺度上直接观察不同电化学状态下电极表界面的结构,有助于从更深层次认识电化学反应机理和性能演化规律,对于改善锂离子电池性能具有重要的指导意义。阐述了球差校正透射电子显微成像技术在研究电极材料表界面结构原子尺度研究中的应用,介绍了特殊的相界面、SEI、表面相变、表面掺杂等,探讨了表界面原子尺度结构与性能的内在关联,提出了改善电池性能的针对性建议,并对锂离子电池未来的发展从提高能量密度、避免固液界面副反应和改善电池性能三个方面进行了展望。

中国兽药典附录原子量表的应用和改进

检索IUPAC国际原子量表锌、硫等元素的原子量,计算杆菌肽锌、氧化锌、硫酸锌、硫代硫酸钠等分子量,按《中国兽药典》附录中原子量表计算值与各论中给出的分子量存在差异,兽药典所附原子量表没有正确应用于正文、附录中。

略谈原子核质量亏损问题

原子核质量亏损问题涉及面较广,与物理学、天文学、气象学、化学等等都有关联,本文仅就原子核亏损值的量子化现象以及与此有关而值得重视的几个问题做一分析,不妥之处,请赐阅者予以指正.1 原子核质量亏损值的计算1.1 各种原子的标记通式“zAX”是各种元素及其同位素的原子标记通式.具体形式如11H（氢）、12D或12H（氢）、24He（氦）、612C（碳）……等等.其中大写字母是元素符号（符号第二个字母应小写）;左下角数字表示质子和电子都是Z个,A叫做X原子的质量数,A-Z=X原子的中子数.1.2 无亏损值的原了量与质量亏损的计算原子的质量叫做“原子量”.如果zAX原子无质量亏损,它的质量mx=ZmH+（A-Z）mn （1）上式mH是氢11H的原子量,mn是中子（n）的质量.原子、质子、中子、电子常用国际上规定的单位,叫做“原子质量单位”,用u作标记符号.1u=1.6605655×10-27千克,是碳612C实测质量的1/12.所以u又叫“碳单位”.以u为单位取六位小数。

Windows消息机制研究

在Windows消息的产生、基本格式、传递、处理等方面对Windows消息机制进行阐述,并介绍在VC++6.0下自定义消息的基本过程,以及利用剪贴板和原子表结合消息实现进程线程间数据交换的基本原理。

Tumor Angiogenesis Correlated with bFGF and FGFR-1 in Lung Cancer

To study the relationship between angiogenesis and the expression of bFGF andFGFR-1 in lung cancer. Methods: The specimens of 56 patients with lung cancer treated with surgerywere collected. Anti-Von Willebrand factor antibody was used to measure microvascular density (MVD)by means of SABC immunohistochemical technique, and antibody to basic fibroblast growth factor(bFGF) and its receptor (FGFR-1) to detect the expression of these three proteins in the tumortissues. The survival time was compared between low MVD and high MVD groups by the Kaplan-Meiermethod. Results: (1) The expression of MVD showed no significant difference in some clinicalcharacteristics, including sex, age, T stage, M stage and pathologic type, but significantdifference in N stage (P 【 0.01) and clinical stage (P 【 0.05). (2) Survival analysis showed thathigh MVD group was associated with a risk of death (P 【 0.01). (3) The expression of bFGF and FGFR-1were both related to lymphatic metastasis and clinical staging (P 【 0.05). (4) Significantdifference was seen between low MVD and high MVD groups in the bFGF expression in lung cancer (P 【0.01), whereas no correlation in FGFR-1. (5) High co-expression of bFGF and FGFR-1 was consistent intumor cells. Conclusion: (1) MVD is a good prognostic factor for patients of lung cancer, and thesame as bFGF. (2) The angiogenesis may be induced after bFGF binding to FGFR-1.

Prediction of Secondary Structure and B Cell Epitope of GH Protein from Acipenser sinensis

[ Objective] The aim was to predict the secondary structure and B cell epitope of growth hormone （GH） protein from Acipenser sinensis. [Method] With the amino acid sequence of GH protein from A. sinensis as the base, the secondary structure of GH protein from A. sinensis was predicted by the method of Gamier-Robson, Chou-Fasman and Karpius-Schulz, and its cell epitope was predicted by the method of Kyte- Doolittle, Emini and Jameson-Wolf. [Result] The sections of 18 -23, 55 -55, 67 -73, 83 -86,112 -114,151 -157 and 209 -211 in the N terminal of GH protein molecule had softer structure and these sections could sway or fold to produce more complex tertiary structure. The sections of 19 -23, 51 -71,84 -95, 128 -139, 164 -176 and 189 -195 in the N terminal of GH protein could be the epitope of B cell and there were flexible regions in these sections or near these sections of GH protein molecule. So the dominant regions could be in these sections or near these sections. [ Conclusion] The research provided the basis for the preparation of monoctonal antibody of GH protein from A. sinensis and provided the reference for the discussion for the molecular regulation mechanism of A. sinensis.

Sequence Analysis of Transcription Factor AtWRKY35 and Construction of Prokaryotic Expression Vector

As members of a super gene family, WRKY transcription factors are widely distributed in higher plants. ln this study, bioinformatic analysis of WRKY35, a member of the WRKY gene family, was carried out. Results indicated that tran-scription factor WRKY35 harbors a WRKYGQK core domain and a Cys2His2 or Cys2His/Cys zinc finger in the 5’ end without transmembrane domain. After PCR amplification and restriction digestion, WRKY35 gene fragment was ligated to prokaryotic expression vector PET28. This study provided basis for expression anal-ysis of WRKY35 protein and subsequent functional identification of WRKY35 gene.

Pilot Study of Molecular Mechanism on Vasculogenic Mimicry in Bi-directional Differentiated Malignant Tumors

Objective: To investigate the role of collagen IV and PAS positive substancesecreted by tumor cells in vasculogenic mimicry (VM) and the effects of VM on tumor cells expressingVEGF. Methods: 158 cases of bi-direction differential malignant tumor specimens withparaffin-embedded were enrolled into our study and made tissue microarray which were dual-stainedwith CD31-PAS and stained with collagen IV. The difference of the areas and distribution withpattern surrounded by between CD31 and PAS positive respectively were identified via grid-counting,as well as the difference of VEGF expression with VE absent and present. Results: The basementmembrane of VM was both PAS and collagen IV positive. VEGF expression in the bi-directiondifferential malignant tumor was higher VM-absent than VM-present and the difference wasstatistically significance in malignant melanoma and alveolar rhabdomyosarcoma (P 【 0.05).Conclusion: PAS positive substance and collagen IV compose the wall of VE and VE could provide theoxygen and nutrition for tumor growth and progression.

Relationship between oxygen species and activity/stability in heteroatom(Zr,Y)-doped cerium-based catalysts for catalytic decomposition of CH_3SH

CeO2,Ce1–xZrxO2,and Ce1–xYxO2–δ(x=0.25,0.50,0.75,and 1.00)have been rapidly synthesized to estimate their catalytic behavior in decomposing CH3SH.The role of oxygen vacancies,and the relationship between the oxygen species and catalytic properties of CeO2 and Zr‐doped and Y‐doped ceria‐based materials are investigated in detail.Combining the observed catalytic performance with the characterization results,it can be deemed that surface lattice oxygen plays a critical role in methanethiol catalytic conversion over cerium oxides.Ce0.75Zr0.25O2 shows higher catalytic activity for CH3SH decomposition due to the large amount of surface lattice oxygen,readily available oxygen species,and excellent redox properties.Ce0.75Y0.25O2–δdisplays better catalytic stability owing to the greater number of oxygen vacancies that would promote bulk lattice oxygen migration to the surface of the catalyst in order to replenish surface lattice oxygen.In addition,the results show that the difference in chemical valence between Ce and the heteroatoms would strongly influence the amount of surface lattice oxygen as well as the mobility of bulk‐phase oxygen in these catalysts,thus affecting their activity and stability.

Ru/FeO_x catalyst performance design: Highly dispersed Ru species for selective carbon dioxide hydrogenation

A series of Ru/FeOx catalysts were synthesized for the selective hydrogenation of CO2to CO.Detailed characterizations of the catalysts through X‐ray diffraction,X‐ray photoelectron spectroscopy,transmission electron microscopy,and temperature‐programmed techniques were performed to directly monitor the surface chemical properties and the catalytic performance to elucidate the reaction mechanism.Highly dispersed Ru species were observed on the surface of FeOx regardless of the initial Ru loading.Varying the Ru loading resulted in changes to the Ru coverage over the FeOx surface,which had a significant impact on the interaction between Ru and adsorbed H,and concomitantly,the H2activation capacity via the ability for H2dissociation.FeOx having0.01%of Ru loading exhibited100%selectivity toward CO resulting from the very strong interaction between Ru and adsorbed H,which limits the desorption of the activated H species and hinders over‐reduction of CO to CH4.Further increasing the Ru loading of the catalysts to above0.01%resulted in the adsorbed H to be easily dissociated,as a result of a weaker interaction with Ru,which allowed excessive CO reduction to produce CH4.Understanding how to selectively design the catalyst by tuning the initial loading of the active phase has broader implications on the design of supported metal catalysts toward preparing liquid fuels from CO2.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences toward preparing liquid fuels from CO2.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.

High Frequency of GFP Gene Transient Expression in Electroporated Zygotes and Early Proembryos of Wheat

Green fluorescent protein (GFP) gene was successfully transferred into the isolated zygotes and early proembryos of wheat (Triticum aestivum L.) by electroporation. A frequency, as high as 46.7% of GFP gene transient expression in early proembryos, was achieved under 150 V/cm electric field strength, 25 muF capacitor, 200 mug/mL of linear plasmid DNA and an electroporation buffer at pH 7.2. Compared with five-day-old proembryos, the zygotes and early proembryos needed lower optimum strength of electric field. After culturing in KM8p medium, the electroporated early proembryos divided and GFP gene expression was observed in daughter cells and subsequent divisions. There was no mosaicism of gene expression in the zygotes and 2-, 4- and 8-celled proembryos.

Quantum-mechanical study of effect of lattice defects on surface properties and copper activation of sphalerite surface

The electronic properties of sphalerite(110)surface bearing Fe,Mn and Cd impurities were calculated using density-functional theory,and the effects of impurities on the copper activation of sphalerite were investigated.Calculated results indicate that both Fe and Mn impurities narrow the band gap of sphalerite surface and lead to the Fermi level shifting to conduction band.Impurity levels composed of Fe 3d and Mn 3d orbital appearing in band gap are beneficial to electrons transfer from the valence band to the conduction band and promote the surface conductivity and the electrochemical activity.The results show that Fe and Mn impurities cannot be replaced by Cu atom,which reduces the exchange sites(Zn)for Cu atom,hence Fe-and Mn-bearing sphalerites are hard to be activated by copper.Cd impurity has little effect on electronic structure of sphalerite surface;however,Cd atom is easily replaced by Cu atom,and this is the reason why the Cd-bearing sphalerite can be easily floated.

Single atom‐based catalysts for electrochemical CO_(2) reduction

Electrochemical CO_(2) reduction reaction(CO_(2)RR),powered by renewable energy,emerges as a promising approach against environmental issues and energy crisis by converting CO_(2) into val‐ue‐added chemicals.Single atom catalysts(SACs)with isolated metal atoms dispersed on supports exhibit outstanding performance for CO_(2) electroreduction,because of their strong single at‐om‐support interactions,maximum metal utilization and excellent catalytic activity.However,SACs suffer from agglomeration of particles,low metal loading,and difficulty in large‐scale production.In addition,molecular catalysts as another single atom‐based catalyst,consisting of ligands molecules connected to metal ions,exhibited similar metal‐nitrogen(M‐N)active centers as that in met‐al‐nitrogen‐carbon(M‐N‐C)SACs,which were highly active to CO_(2) reduction due to their well‐defined active sites and tunability over the steric and electronic properties of the active sites.Nonetheless,molecular catalysts are challenged by generally moderate activity,selectivity and sta‐bility,poor conductivity and aggregation.Many works have been devoted to overcoming these is‐sues of SACs and molecular catalysts for efficient CO_(2)RR,but only limited reviews for systematic summary of their fabrication,application,and characterizations,which were highlighted in this review.Firstly,we summarize recent advanced strategies in preparing SACs for CO_(2)RR,including wet‐chemistry approaches(defect engineering,spatial confinement,and coordination design),other synthetic methods and large‐scale production of SACs.Besides,electrochemical applications of SACs and molecular catalysts on CO_(2)RR are discussed,which involved the faradaic efficiency and partial current density of the desired product as well as the catalyst stability.In addition,ex‐situ and in‐situ/operando characterization techniques are briefly assessed,benefiting probing the active sites and understanding the CO_(2)RR catalytic mechanisms.Finally,future directions for the devel‐opment of single atom‐based catalysts(SACs,molecular catalysts)are pointed out.

Electron bandstructure of kaolinite and its mechanism of flotation using dodecylamine as collector

The bulk electronic structure of kaolinite (001) plane was studied with quantum mechanical calculations. The CASTEP parameterization of ultrasoft pseudopotentials without core corrections was used to optimize the structure of kaolinite bulk and slab models. The results show that Fermi energy of kaolinite (001) plane is 3.05 eV, and the band gap is 4.52 eV. The partial density of states (PDOS) of kaolinite (001) plane indicates that Al-O and Si-O bonds on the mineral surface are highly polar. The oxygen atoms of hydroxyl groups in surface layer are capable of forming hydrogen bond with the head group of cationic collectors. The properties of dodecylamine (DDA) cation were also calculated by density function theory (DFT) method at B3LYP/6-31G (d) level for illuminating the flotation processes of kaolinite. Besides the electrostatic attraction, the mechanism between kaolinite and DDA is found to be hydrogen bonds under acidic condition.

Surface elemental distribution effect of Pt-Pb hexagonal nanoplates for electrocatalytic methanol oxidation reaction

Bimetallic Pt-based catalysts have been extensively investigated to enhance the performance of direct methanol fuel cells(DMFCs) because CO, a by-product, reduces the activity of the pure Pt catalysts. Herein, we synthesized Pt-Pb hexagonal nanoplates as a model catalyst for the methanol oxidation reaction(MOR) and further controlled the Pt and Pb distributions on the surface of the nanoplates through acetic acid(HAc) treatment. As a result, we obtained Pt-Pb nanoplates and HAc-treated Pt-Pb nanoplates with homogeneous and heterogeneous distributions of the Pt-Pb alloy surfaces, respectively. We showed that the MOR activity and stability of the Pt-Pb nanoplates improved compared to those of the HAc-treated Pt-Pb nanoplates, mainly due to the enhanced CO tolerance and the modified electronic structure of Pt under the influence of the oxophilic Pb.

Structural evolution of Pt‐based oxygen reduction reaction electrocatalysts

The commercialization of proton exchange membrane fuel cells(PEMFCs)could provide a cleaner energy society in the near future.However,the sluggish reaction kinetics and harsh conditions of the oxygen reduction reaction affect the durability and cost of PEMFCs.Most previous reports on Pt-based electrocatalyst designs have focused more on improving their activity;however,with the commercialization of PEMFCs,durability has received increasing attention.In-depth insight into the structural evolution of Pt-based electrocatalysts throughout their lifecycle can contribute to further optimization of their activity and durability.The development of in situ electron microscopy and other in situ techniques has promoted the elucidation of the evolution mechanism.This mini review highlights recent advances in the structural evolution of Pt-based electrocatalysts.The mechanisms are adequately discussed,and some methods to inhibit or exploit the structural evolution of the catalysts are also briefly reviewed.

Expression of intestinal trefoil factor, proliferating cell nuclear antigen and histological changes in intestine of rats after intrauterine asphyxia

AIM:To study the expressions of intestinal trefoil factor (ITF) and proliferating cell nuclear antigen (PCNA) and histologic changes in intestine, to investigate the relationship between ITF and intestinal damage and repair after intrauterine hypoxia so as to understand the mechanism of intestinal injury and to find a new way to prevent and treat gastrointestinal diseases. METHODS: Wistar rats, pregnant for 21 d, were used to establish animal models of intrauterine asphyxia by clamping one side of vessels supplying blood to uterus for 20 min, another side was regarded as sham operation group. Intestinal tissues were taken away at 0, 24, 48 and 72 h after birth and stored in different styles. ITF mRNA was detected by RT-PCR. PCNA expression was measured by immunohistochemistry. Intestinal tissues were studied histologically by HE staining in order to observe the areas and degree of injury and to value the intestinal mucosa injury index (IMDI). RESULTS: ITF mRNA appeared in full-term rats and increased with age. After ischemia, ITF mRNA was decreased to the minimum (0.59?.032) 24 h after birth, then began to increase higher after 72 h than it was in the control group (P<0.01). PCNA positive staining located in goblet cell nuclei. The PCNA level had a remarkable decline (53.29±1.97) 48 h after ischemia. Structure changes were obvious in 48-h group, IMDI (3.40±0.16) was significantly increased. Correlation analyses showed that IMDI had a negative correlation with ITF mRNA and PCNA (r= -0.543, P<0.05; r= -0.794, P<0.01, respectively). CONCLUSION: Intrauterine ischemia can result in an early decrease of ITF mRNA expression. ITF and PCNA may play an important role in the damage and repair of intestinal mucosa.

材料星故事(二) ——琼斯·雅各布·贝采利乌斯

琼斯·雅各布·贝采利乌斯(1779—1848,图1)一生星光熠熠,无疑是19世纪上半叶世界最伟大的化学家,没有之一.他测定了45种化学元素的原子质量;首次用元素符号表示并公布了当时已经发现的原子量表;发现了硅、钍、硒等元素;发现"催化现象"并提出"催化"的概念;命名"同分异构体"等等.这些成就,使得贝采利乌斯成为19世纪世界著名的科学家之一,在世界化学和材料史上写下辉煌的一笔.