STUDIES ON REGULARITY OF POLY PHENYLSILSESQUIOXANE CHAINS

IR and ~(29)Si NMR were used to determine the structures of ladderlike polymer polyphenylsilsesquioxanes (PPS). It was found that PPS with lots of defects had a wide and strong absorption band in 1000—1400 cm~(-1) with only one sharp peak at 1137 cm~(-1) while two peaks (1130 and 1045 cm~(-1) were observed for PPS with perfect ladderlike structure. Branching and crosslinking of PPS lead to the reduction of 1045 cm~(-1) peak. ~(29)Si NMR spectra, however, showed two peaks (δ=-78 ppm and -87 ppm when δ_(HMDS)=0 ppm) for defective or branched PPS. The -87 ppm peak is related to the ladderlikely constructed Si atoms and -78 ppm corresponds to defective Si atoms. PPS with defects less than 0.1% chain units was obtained by azeotropic polycondensations.     

A New Brominated Phenylpropylaldehyde and its Dimethyl Acetal from Red Alga Rhodomela confervoides

A new brominated phenylpropylaldehyde and its dimethyl acetal together with a new natural brominated phenol were isolated from Rhodomela confervoides. Their structrues were elucidated as 2-methyl-3-(2,3-dibromo-4,5-dihydroxyphenyl)propylaldehyde, 2-methyl-3-(2,3-di-bromo-4,5-dihydroxyphenyl) propylaldehyde dimethyl acetal and 3-bromo-4,5-dihydroxybenzoic acid methyl ester by spectroscopic techniques including IR, HRFABMS, 1D and 2DNMR experiments.     

FTIR－PAS技术在卟啉类化合物中的应用（Ⅲ）──乙酰丙酮－meso－四－（对－氯代）苯基卟啉稀土配合物的红外光声光谱

研究乙酰丙酮－ｍｅｓｏ－四－（对－氯代）苯基卟啉及其Ｎｄ、Ｓｍ、Ｅｕ、Ｇｄ、Ｔｂ、Ｄｙ、Ｈｏ、Ｅｒ、Ｌｕ配合物在３６００～２２０ｃｍ－１范围内的傅立叶变换红外光声光谱，对其主要谱带进行经验归属．实验结果表明，四－（对－氯代）苯基卟啉与稀土乙酰丙酮配合物中的金属离子配位，削弱乙酰丙酮环上的Ｍ－Ｏ键伸缩振动，使该谱带向低波数方向移动．金属敏感带出现在～１５５８、～１４７４、～１４２７、～１２１９、～７９８、～７３３、～２５０ｃｍ－１．     

制备纳米氧化锌的新方法

以草酸和醋酸锌为原料，用室温固相化学反应首先制备前驱物二水合草酸锌，后者在微波场辐射分解得到产物纳米氧化锌。用XRD，TEM和IR等技术对产物的组成，大小及形貌进行了表征。结果表明：产物纳米氧化锌为粒度分布均匀的球形六角晶系结构，平均粒径约为8nm。     

3-邻氯苯基-3-(5,5二甲基-3-羟基-2-环己烯-1-酮-2-基)丙酸乙酯的合成和晶体结构

标题化合物C19H23O4Cl（4）是由邻氯苯甲醛（1）与5，5-二甲基-1，3-环己二酮（2）、2，2-二甲基-1，3-二氧六环-4，6-二酮（3）在乙醇中反应而得。结构通过单晶X-射线衍射分析确定，其晶体属于单斜晶系，空间群晶体结构用直接法解出，使用全矩阵最小二乘法对原子参数进行修正，最后的偏离因子R＝0．034，Rw＝0．042。在晶体结构中存在一个共轭的烯醇结构。单晶X-射线分析表明；平面1（C（1）～C（6）、Cl）和平面2（C（8）～C（10）、C（12）、C（13））之间的两面角为97．11°，原子C（7）呈变形的四面体构型。     

Synthesis, Structure and Biological Activities of Novel Triazole Compounds Containing N,N-Dialkyldithiocarbamate Moiety

Introduction As an important type of fungicides, triazole compounds are highly efficient, low poisonous and inward absorbent.1-3 At present, the studies on triazole derivatives are mainly concentrated on compounds with triazole as the only active group. The report of triazole compounds that contain both triazole group and other active group in a single molecule has rarely been found. Dialkyl-substituted dithiocarbamate salts have also shown interesting biological effects.4 N,N-Dialkyldithio-…     

Optical Spectroscopy Properties of KMgF3 ：Eu^2＋ Nanocrystals and Powder Synthesized by Microemulsion and Solvothermal Process

IntroductionPerovskite complex fluorides have attracted great ainterest due to their particular physical properties, suchas piezoelectric characteristics[1], ferromagnetic prop-erty[2], nonmagnetic insulator behavior[3], and photo-luminescence host functi…     

一维链状配位聚合物{[Cu(μ-H_2L)(L)Cl](ClO_4)_3}_∞的合成、结构及磁性研究(L=N,N'-双(吡啶基-3-亚甲基)-1,5-二氮环辛烷)

设计合成了一个新型吡啶基二氮环配体L(N,N'-双(吡啶基-3-亚甲基)-1,5-二氮环辛烷)及其铜配位聚合物{[Cu(滋-H2L)(L)Cl](ClO4)3}∞(1),研究了此配合物的晶体结构、光谱及磁性质。该配合物属正交晶系,Pnma空间群,晶胞参数为a=3.5170(17)nm,b=1.0440(5)nm,c=1.1966(6)nm,V=4.394(4)nm3,Z=4。配体L以顺式螯合和反式桥联两种不同的配位形式将铜离子连接起来形成一维链状阳离子结构。     

氟的离子选择电极瞬时电位法测定

研究了氟离子选择电极瞬时电位分析法，其检出限和Nernst响应下限均低于传统电位分析法，空白液切换到试液时瞬时电位达到稳定的峰电位Vp比传统电位法的响应快得多，可以实现小体积试液的快速准确分析；用该法测定了自来水和矿泉水中氟的含量；利用校正曲线的截距和检出限计算了LaF3的溶度积，在0.1mol/L KNO3介质中Ksp(LaF3)=10^-28.45，在0.001mol/L柠檬酸钠＋HAc-NaAc缓冲液（pH=5.50，离子强度I＝0.10mol/L)介质中溶度积K′sp(LaF3)=10^-26.26；据此，计算得柠檬酸与La^3 络合物的稳定常数K1=10^5.46和K2=10^3.99；用离子水合吉氏自由能ΔGh(F^-,g)解释了不同浓度F^-试液瞬时电位的跃迁时间。     

Synthesis of 2-Aminochromene Derivatives Catalyzed by KF／Al2O3

A series of 2-aminochromene derivatives including 2-amino-ben-zo[ h ] chromene, 2-amino-benzo [ f ] chromene and 2-amino-pyrano [3,2-h ]quinolin derivatives was synthesized from aryl-aldehyde, malononitrile or ethyl cyanoacetate and 1-naphthol or 2-naphthoi or 8-hydroxyquinoline in refluxing ethyl alcohol cat-alyzed by KF-Al2O3. The structures were confirmed by X-ray analysis.