Synthesis and Crystal Structure of a Novel Zinc Phosphonate Compound： [Zn（phen）（m-OOCC6H4PO3H）]

A novel zinc（H） metal phosphonate compound [Zn（phen）（m-OOCC6H4PO3H）] 1 （phen = phenanthroline） has been synthesized under hydrothermal conditions. Single-crystal X-ray structure analysis reveals that compound 1 belongs to the triclinic system, space group P1 with a = 9.3356（19）, b = 10.203（2）,c = 10.743（2）A,α = 76.3030（70）, β= 69.2317（51）, y = 84.3833（74）°,V = 929.4（3） ,A3, Z = 2, C2OH15N2O5PZn, Mr = 459.68, Dc = 1.643 g/cm^3,μ= 1.444, mm^-1, F（000） = 468, the final R = 0.0330 and wR = 0.0848. In the structure, the central ion Zn（H） is five-coordinated, linking three O atoms with one from carboxyl and the other two from phosphonyl group. The remained two coordinate sites were occupied by two N atoms from one phen molecule to form the asymmetric unit. Then every two adjacent asymmetric units are bridged by the O atoms from phosphonate group and carboxyl to give rise to a 1D chain along the b axis. These chains are constructed by weak π-π stacking interactions and C-H…π interactions to generate a 3D supramolecular framework.     

Cloning, Expression and Purification of Wheat Acetyl-CoA Carboxylases CT Domain in E. coil

The entire gene of carboxyltransferase（CT） domain of acetyl-CoA carboxylase（ACCase） from Chinese Spring wheat（CSW） plastid was cloned firstly, and the 2.3 kb gene was inserted into PET28a^＋ vector and expressed in E. coil in a soluble state. The （His）6 fusion protein was identified by SDS-PAGE and Western blot. The recombinant protein was purified by affinity chromatography, and the calculated molecular mass（Mr） was 88000. The results of the sequence analysis indicate that the cloned gene（GeneBank accession No. EU124675） was a supplement and revision of the reported ACCase CT partial cDNA from Chinese Spring wheat plastid. The recombinant protein will be significant for us to investigate the recognizing mechanism between ACCase and herbicides, and further to screen new herbicides.     

One-pot synthesis of stable NIR tetracene diimides via double cross-coupling

Tetracene tetracarboxylic diimides have been synthesized based on direct double ring extension of electron-deficient naphthalene diimides involving metallacyclopentadienes. Atomic structure and electronic transitions responsible for their NIR absorption spectra are investigated with quantum-chemical calculations. In light of their unique structure and admirable photophysical and electronic properties, this new molecular skeleton is promising candidate for n-type semiconductors.     

Combined effect of chemically compound graphene oxide‐calcium pimelate on crystallization behavior,morphology and mechanical properties of isotactic polypropylene

The combined nucleation effect of graphene oxide (GO) and calcium pimelate (CaPi) which are chemically compound together (expressed in GO ? CaPi) in isotactic polypropylene (iPP) was investigated. Fourier transform infrared (FTIR), X‐ray diffraction (XRD) and thermogravimetric analysis (TGA) verified that CaPi was chemically compound with GO by chelate bonds. The crystallization behavior and crystalline morphologies of iPP nucleated with different mass ratio of GO and CaPi were investigated. The crystallization peak temperature of iPP nucleated with 0.2 wt% GO ? CaPi with the mass ratio of 1:5 (GO1 ? C5) was increased by 8.3°C when compared with that of pure iPP, and the relative content of β‐crystal reached up to 0.7962. Whereas, the crystallization peak temperature of iPP nucleated with 0.2 wt% GO and CaPi which are blended together by mechanical force (expressed in GO + CaPi) with the mass ratio of 1:5 (GO1 + C5) was only increased by 5.0°C. It was attributed to that the aggregation of GO + CaPi caused the decrease of the crystallization peak temperature, while the GO1 ? C5 uniformly dispersed in the iPP matrix. Unexpectedly, the relative content of β‐crystal of iPP nucleated with 0.02 wt% GO1 ? C5 reached up to 0.8094, and the crystallization peak temperature was increased by 6.7°C compared with that of pure iPP. Meanwhile, the impact strength, tensile strength and heat deflection temperature of iPP nucleated with 0.02 wt% GO1 ? C5 increased by almost 45.86%, 2.03% and 7.7°C, respectively. The iPP nucleated with GO1 ? C5 obtained a balance between stiffness and toughness and the thermo‐mechanical property of nucleated iPP was improved.     

TiB2增强Al2O3陶瓷刀具高速干切削摩擦磨损性能

采用TiB2增强Al2O3陶瓷刀具对淬硬钢进行高速干切削试验,利用切削高温作用下的摩擦化学反应,在刀具表面原位生成具有润滑作用的反应膜,从而实现Al2O3/TiB2陶瓷刀具的自润滑.结果表明:低速干切削时,Al2O3/TiB2陶瓷刀具的磨损机制主要表现为粘着磨损和磨料磨损;而在高速干切削时,刀具的磨损机制主要表现为氧化磨损,刀具表面经由氧化反应生成具有润滑作用的反应膜而起到固体润滑作用,从而使刀具的耐磨性能提高,随着TiB2含量和切削速度的增加,反应膜的减摩抗磨作用增强;而在切削区通入氮气时,由于刀具表面氧化膜形成受阻,刀具的抗磨能力有所降低.     

面向对象的无单元法

介绍了一种用C 进行的面向对象无单元方法程序设计;定义了一些关键的类并将有些类设计成类等级,从而建立了包含权函数、基函数和形函数在内的面向对象无单元法程序类库,在此过程中考虑了无单元法与有限元法的某些联系,保留并重用了面向对象有限元法程序中的一些类。本文提供了一种无单元法大型分析软件开发新途径。     

Machine Learning Approaches for Metalloproteins

Metalloproteins are a family of proteins characterized by metal ion binding, whereby the presence of these ions confers key catalytic and ligand-binding properties. Due to their ubiquity among biological systems, researchers have made immense efforts to predict the structural and functional roles of metalloproteins. Ultimately, having a comprehensive understanding of metalloproteins will lead to tangible applications, such as designing potent inhibitors in drug discovery. Recently, there has been an acceleration in the number of studies applying machine learning to predict metalloprotein properties, primarily driven by the advent of more sophisticated machine learning algorithms. This review covers how machine learning tools have consolidated and expanded our comprehension of various aspects of metalloproteins (structure, function, stability, ligand-binding interactions, and inhibitors). Future avenues of exploration are also discussed.     

掺杂稀土铁磁性纳米复合粉体的制备

采用水热法以FeCl2和KOH为原料制备Fe3 O4粉体,以氧化钇、氧化铕和氧化铽为原料制备Y2 O3:1;Eu3+,5;Tb3+粉体,然后以Fe3 O4粉体,Y2 O3:1;Eu3+,5;Tb3+粉体和三聚氰胺为原料,采用微波烧结法在Ar气气氛下制备FeYO3/Y2 O3:1;Eu3+,5;Tb3+复合粉体,利用XRD衍射仪对各种粉体的结构进行分析,利用扫描电镜对复合粉体的形貌进行观察,并利用振动样品磁强计对复合粉体的磁学性能进行研究.结果表明:复合粉体均呈针状,长度和细度均为纳米级.当Fe3 O4,Y2 O3:1;Eu3+,5;Tb3+和三聚氰胺比例为1:3:4时,所制备的FeYO3/Y2 O3:1;Eu3+,5;Tb3+粉体磁力最强,磁力饱和强度为11.3 emu·g-1.     

不完全边值问题的极小二乘解及其稳定性

定义了一类在部分边界上函数值为0函数的Sobolev空间，并用以讨论部分边界缺乏边值的二阶散度型椭圆型微分方程与其最小范数极小二乘解的稳定性．     

Ameliorating the interfacial issues of all-solid-state lithium metal batteries by constructing polymer/inorganic composite electrolyte

Lithium metal is one of the most promising anodes for next-generation batteries due to its high capacity and low reduction potential.However,the notorious Li de...