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Stevenson NR Schubank RB Shin YM Amaudruz P Delheij PP Healey DC Jennings BK Ottewell DF Sheffer G Smith GR Wait GD Brack JT Feltham A Hanna M Johnson RR Rozon FM Sossi V Vetterli D Weber P Grion N Rui R Kohler M Ristinen RA Mathie EL Tacik R Yeomans M Gossett CA Wagner GJ 《Physical review letters》1990,65(16):1987-1990
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Zhu Hai-Liang Huang Pei Duan Chun-Ying Zheng Li-Min Liu Yong-Jiang Wu Mei-Fang Tang Wen-Xia 《Transition Metal Chemistry》1999,24(4):380-383
An azide-bridged polymeric cationic chain complex, [LCu2(N3)2]n(ClO4)2n
·n(H2O)**, where L=the dinucleating macrocyclic ligand bis-p-xylylBISDIEN, has been prepared and characterized by x-ray crystallography, u.v.-vis and i.r. spectra, and by magnetic measurements. The structure consists of cationic azide-bridged [LCu2(N3)2]2+ (unit) chains, non-coordinated perchlorate anions and crystallized water molecules. The azide anion is bound to two copper atoms in neighboring units with an end-to-end bridging mode. In each unit, the copper atoms have a different coordination geometry; Cu(1) is a four-coordinated, distorted square-planar geometry, whereas Cu(2) is a five-coordinated, distorted square-pyramid. The electronic spectra of the title complex differ in anhydrous and in aqueous MeCN solutions, indicating that dissociation and solvation occur in aqueous solutions. The characteristic i.r. absorptions of azides and perchlorates are described. Magnetic moments vary from 2.05 (B.M.) at 300K to2.01 (B.M.) at 80K, which suggests that very weak interactions exist between the metals. 相似文献
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微波场中甲烷部分氧化制合成气 Ⅱ.Co/ZrO_2催化剂在微波场中的升温行为及催化活性 总被引:4,自引:0,他引:4
近年来,甲烷部分氧化制合成气(POM)的研究一直十分活跃[1,2].前文报道了用于甲烷部分氧化制合成气的镍基催化剂(Ni/La2O3)在微波场中的升温行为和催化活性[3],发现在达到相同的CH4转化率时,微波活化方式下的催化剂床层温度比常规加热低得多... 相似文献
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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. 相似文献
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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 总被引:4,自引:0,他引:4
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(C10H8N2O42-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,Dc=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。 相似文献
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在无溶剂绿色化学条件下,将α-萜品烯-马来酸酐加成物(1)与取代苯(硫)脲发生N-酰化反应,合成了4个N-(1-异丙基-2-羧基-4-甲基二环[2.2.2]-5-辛烯-3-羰基)-N′-芳基(硫)脲化合物(3a~3d),并由IR、UV-Vis、MS、1HNMR、13C NMR和元素分析确认了目标产物的结构。生物活性测试表明,其中3个化合物(3a、3b和3c)具有植物激素作用。 相似文献
30.
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. 相似文献