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1.
结合以往的教学实践,针对学生学习分析化学课程中存在的一些问题,就如何培养医学检验和卫生检验专业学生的学习分析化学兴趣,进行了几点简要的探讨.  相似文献   
2.
冯超  张灵美  杨雨濛  赵红 《无机化学学报》2023,39(12):2377-2384
采用溶剂热法合成了一种新型的钴(Ⅱ)基配合物,即{[Co(Hppc)2][Co2(4,4''-bipy)(H2O)4](SO42·2H2O}n1),其中H2ppc=5-(3-吡啶基)-1H-吡唑-3-羧酸,4,4''-bipy=4, 4''-联吡啶。配体H2ppc是由吡啶环、吡唑环和羧基共同组成,同时兼具了刚性和柔性。通过单晶X射线衍射对配合物1进行了结构测定。结果显示所合成的配合物1结晶在单斜晶系C2/c空间群,包括2个晶体学独立部分:二维层状[Co(Hppc)2]和一维链状[Co2(4,4''-bipy)(H2O)4]2-,并形成具有{44·62}{4}2拓扑网络结构的共晶化合物。此外,配合物1呈现出良好的电化学发光(ECL)性能以及良好的超级电容器性能。  相似文献   
3.
1 INTRODUCTION The interest in vanadium chemistry from a biolo-gical and pharmacological perspective has explodedover the past 20 years. This is mainly based on thediscoveries of the insulin-like effect of vanadium compounds[1, 2], and the presence of vanadium in certainhaloperoxidases and nitrogenases[3, 4]. Vanadium complexes with organic ligands mightbe candidates for therapy of diabetes, consequentlydesign and synthesis of new complexes are of greatinterest recently[5, 6]. On consid…  相似文献   
4.
Three new seco-polycyclic polyprenylated acylphloroglucinols (PPAPs), ascyronones A–C (13), and a new biosynthetic precursor, ascyronone D (4), were isolated from Hypericum ascyron together with three known analogues (57). Compounds 1 and 2, sharing an unusual seven-membered carbon core fused with a γ-lactone ring, could be derived from 1,9-seco-PPAPs via further rearrangement. A biomimetic transformation from 5 to 1 was performed by using base-driven retro-Claisen and rearrangement cascade reaction, which further confirmed the structure of 1 and shed light to its possible biosynthetic pathway. Interestingly, all these compounds are decorated with a methyl group at C-5 instead of a prenyl or geranyl group in many other PPAPs. The isolates were evaluated for their inhibitory activities against five human tumor cell lines.  相似文献   
5.
2-羟基-1-萘甲醛半碳酰腙铬(Ⅲ)配合物的合成和晶体结构   总被引:1,自引:0,他引:1  
本文合成了2-羟基-1-萘甲醛半碳酰腙铬(Ⅲ)单核配合物,通过红外、紫外、荧光光谱和单晶X-射线衍射等方法对其结构进行了表征。其晶体结构属于单斜晶系,空间群C2/c。光谱数据表明:配体2-羟基-1-萘甲醛半碳酰腙作为三齿螯合剂,通过酚氧,亚胺基氮和酮氧与铬(Ⅲ)离子配位。其铬(Ⅲ)中心为扭曲的六配位八面体几何构型。  相似文献   
6.
The novel chromium(Ⅲ) complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pbca with a = 8.9849(13), b = 12.0475(16), c = 34.522(5)A, V = 3736.9(9)A3, Z = 8, C16H18C1CrN6O5, Mr= 461.81, De= 1.642 g/cm^3, F(000) = 1896,A(MoKα) = 0.799 mm^-1, the final R = 0.0370 and wR = 0.0827 for 2908 observed reflections with I 〉 2σ(I). The interaction between the chromium(Ⅲ) complex with calf thymus DNA (Ct-DNA) has been investigated by absorption spectroscopy, fluorescence spectroscopy and viscosity measurements. The results indicated that the complex was bonded to Ct-DNA through a non-classical intercalative mode.  相似文献   
7.
可生物降解长效缓释抗肿瘤药物的研究   总被引:1,自引:1,他引:1  
用铝复合催化剂合成了高分子量的PLA,其降解寿命在十个月以上。进行了含有5-Fu抗肿瘤药物膜在生理盐水中的释放试验。结果表明,释放速度可通过改变共聚物的组成和成膜工艺来控制。  相似文献   
8.
在甲醇体系中乙酰丙酮氧钒与邻香草醛缩牛磺酸钾席夫碱在乙二胺存在下反应得到一个双核钒配合物。通过红外光谱和X-射线单晶衍射对其进行了表征。晶体结构表明该化合物的晶体属于三斜晶系,P1空间群,晶胞参数为a=0.898 67(19)nm,b=1.159 3(3) nm,c=1.200 0(3) nm,α=106.872(3)°,β=102.718(4)°,γ=94.905(3)°,Z=2。通过紫外吸收光谱法和循环伏安法研究了钒配合物与小牛胸腺DNA间的相互作用。紫外吸收光谱法得到配合物与DNA的结合常数为1.77×104 dm3·mol-1。  相似文献   
9.
Zou J  Du X  Pang G  Shi YM  Wang WG  Zhan R  Kong LM  Li XN  Li Y  Pu JX  Sun HD 《Organic letters》2012,14(12):3210-3213
Ternifolide A (1), a new diterpenoid featuring a unique 10-membered lactone ring formed between C-6 and C-15, along with ternifolide B (2), a nor-diterpenoid, and ternifolide C (3) were isolated from the leaves of Isodon ternifolius. Both H-8 and H-9 being α-orientations in compound 1 were found for the first time. The absolute configurations of 1 and 3 were confirmed by X-ray diffraction study. Compounds 1 and 3 were evaluated for their cytotoxicity.  相似文献   
10.
Shi YM  Li XY  Li XN  Luo X  Xue YB  Liang CQ  Zou J  Kong LM  Li Y  Pu JX  Xiao WL  Sun HD 《Organic letters》2011,13(15):3848-3851
Schicagenins A-C (1-3), three unprecedented nortriterpenoids characterized with a tetracyclic oxa-cage motif and C(9) side chain, were discovered from the leaves and stems of Schisandra chinensis. Their structures were determined on the basis of extensive spectroscopic analysis, and the absolute stereochemistries were established by single-crystal X-ray diffraction and CD experiments. A plausible biosynthetic pathway of 1-3 was also discussed.  相似文献   
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