选择性远程DEPT~(13)C NMR新技术用于新阔叶千里光碱氮氧化合物的结构测定和谱峰归属研究

从湖北蟹甲草根茎中分得一个新的生物碱,选择性远程DEPT~(13)C NMR新技术用于识别NMR信号归属和连接被季碳及杂原子分割的质子自旋系统,确定其结构为新阔叶千里光碱的氮氧化物,如(1)所示。     

电流控阈技术及二值 I2L 施密特电路设计

电流控阈技术及二值Ｉ~２Ｌ施密特电路设计黄瑞祥，杭国强（杭州大学电子工程系杭州３１００２８）在数字电路中，以往对施密特电路的分析与研究大多局限于用电压信号来表示逻辑值的电路，例如ＴＴＬ、ＣＭＯＳ、ＥＣＬ等电路［１－３］．然而，对于以电流为信号的电流型?..     

Current Trend in Synthesis,Post‐Synthetic Modifications and Biological Applications of Nanometal‐Organic Frameworks (NMOFs)

Since the early reports of MOFs and their interesting properties, research involving these materials has grown wide in scope and applications. Various synthetic approaches have ensued in view of obtaining materials with optimised properties, the extensive scope of application spanning from energy, gas sorption, catalysis biological applications has meant exponentially evolved over the years. The far‐reaching synthetic and PSM approaches and porosity control possibilities have continued to serve as a motivation for research on these materials. With respect to the biological applications, MOFs have shown promise as good candidates in applications involving drug delivery, BioMOFs, sensing, imaging amongst others. Despite being a while away from successful entry into the market, observed results in sensing, drug delivery, and imaging put these materials on the spot light as candidates poised to usher in a revolution in biology. In this regard, this review article focuses current approaches in synthesis, post functionalization and biological applications of these materials with particular attention on drug delivery, imaging, sensing and BioMOFs.     

二水·2-羰基丙酸水杨酰腙合铜(Ⅱ)配合物的晶体结构及生物活性

在水中,以2-羰基丙酸水杨酰腙与硫酸铜反应,制得新配合物Cu(C₁₀H₈N₂O₄)(H₂O)₂(C₁₀H₈N₂O₄^2-为2-羰基丙酸水杨酰腙负离子),并以水为溶剂培养了单晶,测试了晶体结构,该单晶为深绿色,属单斜晶系,空间群为C2/c,晶胞参数a=1.1297(1)nm,b=0.9824(8)nm,c=2.1973(3)nm,β=91.91(8)°,V=2.43749(8)nm³,Z=8,μ=1.817mm^-1,D_c=1.743Mg·m^-3,F(000)=1304,R=0.0264,wR=0.0654,GOF=1.052。其测试结果表明在配合物中Cu²⁺处于五配位的四方锥配位环境,配位原子分别来自1个三齿配体2-羰基丙酸水杨酰腙负二价离子的2个O原子和1个N原子,2个水分子中的O原子,其中1个水分子的O原子处于四方锥的锥顶,锥底的配位原子基本处于同一平面上。对该配合物所作的皿内抑菌试验和盆栽活体实验表明,配合物对小麦条锈病、白菜黑斑病及辣椒疫霉菌等分别有96%、89%、100%的抑制率,且有一定的助长作用。     

Silica hybrid nanocomposites

In this work we present experimental results about the formation, properties and structure of sol — gel silica based biocomposite containing Calcium alginate as an organic compound. Two different types of silicon precursors have been used in the synthesis: tetramethylortosilicate (TMOS) and ethyltrimethoxysilane (ETMS). The samples have been prepared at room temperature. The hybrids have been synthesized by replacing different quantitis of the inorganic precursor with alginate. The structure of the obtained hybrid materials has been studied by XRD, IR Spectroscopy, EDS, BET and AFM. The results proved that all samples are amorphous possessing a surface area from 70 to 290 m²/g. It has also been established by FT IR spectra that the hybrids containing TMOS display Van der Walls and Hydrogen bonding or electrostatic interactions between the organic and inorganic components. Strong chemical bonds between the inorganic and organic components in the samples with ETMS are present. A self-organized nanostructure has been observed by AFM. In the obtained hybrids the nanobuilding blocks average in size at about 8–14 nm for the particles.     

Fibers and 3D mesh scaffolds from biodegradable starch-based blends: production and characterization

The aim of this work is the production of fibers from biodegradable polymers to obtain 3D scaffolds for tissue engineering of hard tissues. The scaffolds required for this highly demanding application need to have, as well as the biological and mechanical characteristics, a high degree of porosity with suitable dimensions for cell seeding and proliferation. Furthermore, the open cell porosity should have adequate interconnectivity for a continuous flow of nutrients and outflow of cell metabolic residues as well as to allow cell growth into confluent layers. Blends of corn starch, a natural biodegradable polymer, with other synthetic polymers (poly(ethylene vinyl alcohol), poly(epsilon-caprolactone), poly(lactic acid)) were selected for this work because of their good balance of properties, namely biocompatibility, processability and mechanical properties. Melt spinning was used to produce fibers from all the blends and 3D meshes from one of the starch-poly(lactic acid) blends. The experimental characterization included the evaluation of the tensile mechanical properties and thermal properties of the fibers and the compression stiffness, porosity and degradation behavior of the 3D meshes. Light microscopy picture of 3D meshes.     

Synthesis and nitration of 4,6(4,8)-dimethyl-4-methyl-6(8)-methoxy-1,2,3,4-tetrahydrospiro [quinoline-2-cyclohexanes]

The cydization of 1-allyl-1-arylaminocyclohexanes under conditions of acid catalysis afforded 1,2,3,4-tetrahydro-4-methylspiro [quinoline-2-cyclohexanes] methyl (methoxy)-substituted in the phenylene ring. Their mono- and dinitro derivatives were synthesized, and their structure was established. Propositions on the direction of the nitration reaction of these heterocyclic compounds were expressed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 784–788, June, 1993.