[Sm(CH_3CN)_9]·(AlCl_4)3·CH_3CN的合成和晶体结构

关于过渡金属乙腈配合物的合成和催化性能的研究在文献中已有很多报道。但是,含稀土元素的这类配合物的合成及催化性能的研究直到1986年才见报道。Thomas利用金属Eu和NOBF_4在乙腈中的反应制得了配合物[Eu(CH_3CN)_3(BF_4)_3]_x。本文报道了新乙睛稀土配合物[Sm(CH_3CN)_9]·(AlCl_4)_3·CH_3CN的合成及其晶体结构与分子结构。 (一) 实验 所有操作都在氩气保护下进行。无水SmCl_3用NH_4Cl法制得。AlCl_3经升华后使用。CH_3CN经P_2O_5干燥蒸馏。IR用Perkin-Elmer FTS-20红外光谱仪测定。     

Co／Pd催化剂上CH4／CO2等温两步反应直接合成乙酸的热力学

采用量子化学密度泛函理论对CH4/CO2两步法合成乙酸反应中表面碳化物CHx (x=0～3)在Co和Pd模型表面上不同吸附活性位上的吸附能、空间构型和反应吉布斯自由能进行了系统性的比较研究. 计算结果表明, CH4/CO2两步反应在单一金属Co或Pd催化剂上在常压等温条件下不能有效进行,但在Co和Pd组成的双金属催化剂上,两步反应在常压等温下可以进行. 在Co和Pd双金属催化剂上,金属Co活化CH4生成金属碳化物CHxCo(x=0, 1)为热力学允许反应,其后CHx溢流到金属Pd上形成CHyPd (y=1～3)碳化物,最后CO2插入CHyPd生成乙酸,后两者在常压等温情况下也为热力学允许反应,并且在435 K以上可以与前者构成等温循环. 计算结果与实验结果吻合.     

高分子化Si桥联茂金属催化剂的合成及其催化乙烯聚合反应

合成了硅桥上含乙烯基团的硅桥联茂金属催化剂[(CH_2=CH)CH_3Si(C_5H_4) _2]ZrCl_2 (3)，并通过IR, ~1H NMR对化合物进行了表征，3在AIBN的引发下与苯 乙烯共聚形成高分子化的茂金属催化剂4。研究了3和4对乙烯聚合的能力，考察了 n(Al)/n(Zr)'温度对催化剂活性的影响。     

C_(60)及其碱金属衍生化合物

本文综述了C_(60)的分子结构,合成,晶体结构和相变,主要物理化学性能,以及碱金属C_(60)化合物M_3C_(60),M_4C_(60)和M_6C_(60)的制备,晶体结构和超导性。     

碳氟醇与阴离子表面活性剂的相互作用

测定了不同比例的C_(10)_H_(21)SO_4Na-C_3F_7CH_2OH、C_7F_(15)COONa-C_3H_7CH_2OH混合水溶液的表面张力,加入C_3F_7CH_2OH可增加阴离子表面活性剂的表面活性;在表面层中,C_3F_7CH_2OH与C_(10)H_(21)SO_4Na间分子相互作用比C_3F_7CH_2OH-C_7F_(15)COONa体系弱;这是由于CF链与CH链间“互疏”作用的结果;随着C_3F_7CH_2OH浓度增加,对C_(10)H_(21)SO_4Na胶团反离子结合度也随之增加。     

边界条件下铁镍纳米合金与一碳氯化物反应性能的研究

液相合成铁系元素及其合金纳米微粉,一般是用硼氢化物[1￣4]等强还原剂将低价的Fe2 、Co2 、Ni2 还原为金属单质。前文[5]在合成须状Fe-Ni-B-O纳米合金及其组成方面进行了报道。实验中发现,通氢还原的纳米合金在少量氧气的存在下,可以和氯化物反应,产物为FeCl2、NiCl2和Cl2,氯化物中的碳元素镶嵌在纳米合金微粉表面,本文将对所合成的纳米合金与CCl4反应的反应性能进行研究,并对反应的机理做简单的描述。该项研究工作目前国内外尚未见文献报道。1实验部分1.1实验仪器及试剂AgNO3;K2Cr2O7;CCl4;CHCl3;CH2Cl2;200mg·L-1HCl(1 1)…     

1979年中国科学院上海有机化学研究所研究生有机化学招考试题

(一)用方程式写出下列的合成反应:1.从合成2.用CH_3CH_2CH_2COCl和苯合成C_6H_5CH_2CH_2CH_2CH_3     

二价钇配位化合物的ESCA的表征

本文用钇的3P_(1/2)和3P(3/2)的间距及3P能级的半高宽(FWHM)的变化以及￥4s能级的多重分裂确定了新合成的有机金属化合物的价态。在铝靶上,利用轫致辐射诱导的俄歇谱,对高动能的YL_3M_(45)M_(45)峰(大约1737eV)进行了研究,进一步验证了钇的价态。这与X射线衍射的结果相互补充。     

甾体不对称合成的研究 14.两个光学活性甾体CD环合成原的新法合成

光学活性甾体CD环合成原1a和2a可分别从3a和3b制得.我们已从γ-羰基亚砜5合成了光学活性合成原4.本文报道从一个新的成环试剂7b与2-乙基-环戊烷-1,3-二酮反应得到的三酮硫醚8a来合成2b和4. 二噻烷6a经羟乙基化(n-BuLi,CH_2CH_2O,THF)、水解(HgCl_2-CaCO_3,80％ CH_3CN-     

两种固体荧光有机-无机杂化物的合成、结构及强红光发射（英文）

采用(E)-4-(4-(diphenylamino)styryl)-1-methylpyridinium iodide(DPASPI,DPASP=(E)-4-(4-(diphenylamino)styryl)-1-methylpyridinium),设计合成2种新型有机-无机杂化物(DPASP)_2[Zn(NCS)_4]·2CH_3OH(1)和{(DPASP)_2[Cd(SCN)(NCS)_3]·2CH_3OH}n(2)。通过单晶X射线衍射进行了表征,结果表明杂化物1和2是由有机吡啶阳离子和异硫氰酸金属配阴离子组成的,具有不同空间结构。通过1H NMR谱图解释了离子间相互作用。对具有高量子产率的杂化物1和2的红光发光性质进行了研究。     

用毛细管色谱法测定丙烯腈及其合成过程的副产物

用毛细管色谱内标定量法,同时测定丙烯腈及其合成过程的副产物,此法快捷、方便、具有较高的准确度。     

槲皮素修饰的双层脂膜的伏安研究

槲皮素修饰的从层脂膜作为研究抗病毒药物的一种模型体系,用循环伏安法测定了槲皮素在脂膜界面上的氧化还原性质和配位性质。在电位扫描过程中,微量铜离子能催化槲皮素的氧化,当双层脂膜的两侧存在着合适的氧化还原偶时,就会产生跨膜的电子传递。     

MECHANISM OF PHOTOREDUCTION OF THIAZINE DYES BY EDTA STUDIED BY FLASH-PHOTOLYSIS-I

Abstract— The photoreduction of thiazine dyes by ethylene diamine tetraacetic acid (EDTA) was investigated by Rash photolysis. This reaction was found to occur according to a three-step mechanism. the first being the formation of the dye triplet state followed, in weakly acid solutions, by protonation. During the second step, the triplet state of the dye disappears through two competing processes: spontaneous deactivation and reaction with EDTA, which leads to the semireduced dye. The third step leads to the leucodye. It is shown that the overall quantum yield of photoreduction is governed by the second step and can be calculated from the ratio of the rate constants of the two elementary processes involved in this step. This ratio was measured over a wide pH range.     

电导率法和光度法测定乙醇含量

通过测定不同含水量的硝酸钴乙醇溶液的电导率和吸光度，从而建立回归方程，并通过显著性检验，发现溶液的水含量与其电导率成正相关；与其在520nm波长处的吸光度成负相关。根据此特性，可用于乙醇中水含量的快速测定。     

氨基修饰超高交联树脂对单宁酸的吸附行为及机理研究

选用单宁酸作为天然有机酸中典型中分子、高水溶性有机酸,系统研究了氨基修饰超高交联树脂对单宁酸的吸附行为和机理.吸附等温线表明氨基修饰超高交联树脂WJN-08对单宁酸有较高的吸附容量,其静态饱和吸附量比传统商业吸附剂高15%以上;吸附表面分析表明离子键、π-π共轭作用和阳离子-π键是重要吸附作用力;吸附热力学试验表明树脂WJN-08吸附单宁酸是化学吸附主导,吸附焓变在20~22 kJ mol-1;吸附动力学试验表明树脂WJN-08吸附单宁酸速率同时受控于颗粒内扩散和膜扩散过程.动态小柱吸附-脱附实验表明树脂WJN-08对单宁酸有较好的吸附-脱附性能,饱和吸附量和穿透吸附量分别为24.43 mg g-1和19.56 mg g-1,脱附率为98.6%。     

POLYCAPROLACTAM MODIFIED BY POLYBENZIMIDAZOLE

Three polycaprolactam samples modified by 0.05—0.50% polybenzimidazole (PBI) by weight were prepared. Their structure and mechanical properties were characterized by means of FT-IR, SEM, DTA, density tensile, impact and viscoelastic method. PBI delayed the superimposed polymerization-crystallization process of the activated anionic polymerization of caprolactam. The monomer casting (MC) nylons modified by PBI had lower crystallinities, lower T_g and more nearly perfect spherulites than MC nylon itself, and showed a typical toughening effect.     

POLYCAPROLACTAM MODIFIED BY POLYPHENYLQUINOXALINE

Three polycaprolactam samples modified by 0.05—0.50% polyphenylquinoxaline(PPQ)by weight were prepared.Their structure and mechanical properties were characterized by FT-IR, SEM, density, tensile, impact, DTAand visco-elastic method, PPQ induced the formation of "crystal grains" distributed evenly over nylon spherulites in modified samples, which were observed for the first time, and strengthened modified samples. Modified nylons had higher crystallinities, higher T_g, more nearly perfect spherulites than MC nylon itself, and showed typical reinforcing effect on mechanical properties.     

POTENTIATION OF OXIDATIVE DAMAGE TO PROTEINS BY ULTRAVIOLET-A AND PROTECTION BY ANTIOXIDANTS

We have studied the damage of alcohol dehydrogenase (ADH) and glyceraldehyde 3-phosphate dehydrogenase (GAPD) induced by Fe++/EDTA + H2O2 in combination with UV-A (main output at 365 nm). Enzyme inactivation, formation of hydroxyl radicals (measured in the absence of enzymes), increase in protein carbonyls, oxidation of sulfhydryl (SH) groups, loss of native protein fluorescence, and enhanced protease degradation were used to determine protein damage. Hydroxyl radical production was greatly enhanced by the combination of UV-A with Fe++/EDTA + H2O2. The combined treatment increased protein carbonyls but decreased native protein fluorescence and SH groups. The combined treatment caused turbidity in GAPD but not in ADH, whereas trypsin susceptibility was increased more in ADH than in GAPD. These measurements of protein oxidation correlated well with enzyme activities. Glyceraldehyde 3-phosphate dehydrogenase and dithiothreitol were most protective against such damage, while hydroxyl radical and singlet oxygen scavengers were partially effective. Superoxide dismutase had no effect. Thus, UV-A potentiation of protein damage induced by FE++/EDTA + H2O2 appeared to involve hydroxyl radicals and perhaps singlet oxygen but not superoxide radicals. The damage to proteins induced by combination of UV-A with physiological oxidants, iron ions and H2O2 may be relevant to UV-A-induced skin and tissue damage.     

SINGLET MOLECULAR OXYGEN QUENCHING BY SATURATED AND UNSATURATED FATTY-ACIDS AND BY CHOLESTEROL

The rate constants of molecular singlet oxygen quenching by saturated and unsaturated fatty-acids and by cholesterol-membrane critical components - membrane critical components - have been measured by time resolved detection of the 1270 nm phosphorescence of singlet molecular oxygen [O2(1deltag)]. We have determined (i) an increment of 5.7 x 10(2)M(-1)s(-1) per -CH2- in C6D6 and CD3OD for saturated fatty acids between C4 and C20, (ii) an increment of 3 x 10(4)M(-1)s(-1) per non-conjugated cis-double bond for C18 unsaturated fatty acids, identical in C6D6 and DC3OD, (iii) a lower quenching rate constant by a factor of 2.7 for the trans-C16 and trans-C18 as compared to the corresponding cis-monounsaturated fatty acids, (iv) a rate constant of O2x(1deltag) quenching by cholesterol of 5.7 x 10(4)M(-1)s(-1) in benzene. These rate constants are compared to those obtained for other membrane cellular components.     

PHOTOSENSITIZATION BY ANTIMALARIAL DRUGS

Abstract The antimalarial drugs, chloroquine, hydroxychloroquine, quinine, quinacrine, amodiaquine and primaquine and the local anaesthetic, dibucaine, were tested for in vitro photosensitizing capability by irradiation with 365 nm UV light in aqueous solutions. The ability of these compounds to photosensitize the oxidation of 2,5-dimethylfuran, histidine, tryptophan or xanthine, and to initiate the free radical polymerization of acrylamide was examined in the pH range 2-12. Chloroquine and hydroxychloroquine show maximal photooxidative behaviour when in the monocation form at pH 9, in contrast to quinine which is extremely efficient as the dication below pH 4. This pattern appears to relate to the fluorescence yield as a function of pH. Chloroquine in the monocation or neutral form was found to undergo dechlorination upon irradiation, and this correlates directly with its ability to initiate photo-polymerization of acrylamide. Quinine also gives rise to small polymerization rates, attributed to photo-ionization in the quinoline ring, yielding a cation radical. Amodiaquine, primaquine and quinacrine do not have significant photochemical activity in aqueous solution. Dibucaine exhibits a strong photosensitizing capability at low pH, similar to quinine.