配合物[Hpip] [(salen)FeⅢ(OX)]的晶体结构和异三核配合物的合成与磁性

合成了含有草酸根(OX)桥基的铁(Ⅲ)的配合物配体[Hpip] [(salen)Fe^Ⅲ(OX)](pip=哌啶;salen=N,N'-二水杨醛缩乙二胺),并解析了其晶体结构.利用这一含有草酸根桥基的配合物配体组装了3个新的异三核配合物[(salen)Fe^Ⅲ(μ-OX)]₂[M^Ⅱ(H₂O)₂]·nH₂O[M^Ⅱ=Cu^Ⅱ(1), Ni^Ⅱ(2),Fe^Ⅱ(3)],并进行了结构表征,变温磁化率(4.2~300 K)测定结果均未表现出非正规自旋态的类铁磁行为.通过计箅和分析,讨论了满足"非正规自旋态"的充分和必要条件>     

水溶性羧酸咔咯铁(Ⅲ)配合物对DNA的氧化断裂作用

合成了5,10,15-三(4-羧基-苯基)咔咯铁配合物(Fe^ⅢTCPC), 采用紫外-可见光谱、 荧光光谱、 圆二色光谱和黏度法研究了Fe^ⅢTCPC与小牛胸腺DNA(ct-DNA)的相互作用, 并用琼脂糖凝胶电泳研究了氧化剂参与下Fe^ⅢTCPC对pBR22 DNA的氧化断裂能力. 结果表明, Fe^ⅢTCPC与DNA的作用方式为外部结合模式, 其结合常数K_b=1.96×10⁵ L/mol. 在过氧化氢(H₂O₂)或叔丁基过氧化氢(TBHP)为氧化剂条件下, Fe^ⅢTCPC展现出良好的DNA氧化断裂能力, 且TBHP的氧化断裂效率比H₂O₂好. 用H₂O₂和TBHP为氧化剂时, Fe^ⅢTCPC可能是通过活性Fe^Ⅴ-oxo机制对DNA氧化断裂.     

针状纳米NixZn1－xFe2O4的制备及磁性能

以FeCl₂, Zn(NO₃)₂, Ni(NO₃)₂为原料, 利用化学沉淀法制得了针状纳米α-FeOOH, 并借助针状α-FeOOH做为中间体, 采用柠檬酸法在针状纳米α-FeOOH表面包裹镍和锌的柠檬酸络合物后, 于不同温度煅烧后制得了针状纳米Ni_xZn_1－xFe₂O₄. 利用红外光谱仪(IR)、X射线衍射技术(XRD)、透射电子显微镜(TEM)对样品的物相﹑晶格常数、形貌和粒径进行表征, 并利用振动样品磁强计(VSM)对样品进行磁性能研究. 结果表明: 利用化学沉淀-柠檬酸法制得的Ni-Zn铁氧体样品保持了中间体α-FeOOH的针状形貌, 所得样品的直径在40 nm左右, 长度约600 nm, 长径比大于15. 随着煅烧温度的升高样品直径有所增加, 长径比下降, 随着x值的增加, Ni_xZn_1－xFe₂O₄样品的晶格常数a从0.8442 (x＝0)逐步减少到0.8353 (x＝1.00), 矫顽力(Hc)从63.5 Oe (x＝0)逐步增加到358.7 Oe (x＝1), 饱和磁化强度(M_s)先增加后减小, 当x＝0.6时达到最大为58.9 emu/g. 与相似条件时制备的不定型Ni_xZn_1－xFe₂O₄相比, 由于针状Ni_xZn_1－xFe₂O₄的各向异性增大, 而表现出明显的硬磁性.     

镝掺杂铁氧体纳米晶的制备、表征和磁性

采用化学共沉淀法制备出了镝掺杂铁氧体纳米晶, 利用透射电子显微镜(TEM)、X射线衍射仪(XRD)、傅立叶红外光谱仪(FTIR)、古埃磁天平、振动样品磁强计(VSM)、X射线能谱仪(EDX)等仪器对产物进行了表征, 研究了Dy^3＋掺杂量对铁氧体纳米晶的结构、磁性和粒度的影响. 结果表明: 适量稀土元素镝离子的掺杂可以提高尖晶石型铁氧体的磁性、降低矫顽力, 当n(Fe^3＋)∶n(Dy^3＋)＝14∶1时其磁性最强. Dy^3＋替代或充填进入了尖晶石晶格, 且主要占据B位. 掺杂了镝的铁氧体磁性纳米粒子粒度变小, 且分布更集中、均匀, 当Dy^3＋加入量为n(Fe^3＋)∶n(Dy^3＋)＝14∶1时铁氧体纳米粒子的平均粒径由掺杂前的14 nm降低到到8 nm. 这种具有超顺磁性的软磁铁氧体纳米晶可应用于纳米磁液领域.     

电化学沉积制备半导体CuInSe2薄膜

本文报道恒电位法在pH为1.35的Cu₂SO₄、SeO₂、In₂(SO₄)₃溶液中,在Ti电极上电化学沉积制备CuInSe₂纳米薄膜.研究络合剂柠檬酸和酒石酸对制备CuInSe₂纳米薄膜的影响.扫描电子显微镜(SEM)结果表明,加入络合剂后,电化学沉积的薄膜表面颗粒分布更均匀、致密.X射线衍射(XRD)分析显示,制备的CuInSe₂薄膜是黄铜矿和闪锌矿相的混和物,添加柠檬酸和酒石酸后,衍射峰增强,晶形变好.制备的薄膜颗粒尺寸大小在250nm左右,造成粒度增大的原因是由于颗粒的团聚作用.     

共沉淀-熔盐焙烧法制备Y2O3:Eu及其发光性能的研究

采用共沉淀-熔盐焙烧法制备了Y2O3：Eu红色荧光粉,研究分析了EDTA、柠檬酸＋氨水、淀粉等3类络合剂、沉淀温度及熔盐对其发光性能、粒度及形貌等的影响.研究结果表明： 采用柠檬酸＋氨水为络合剂、草酸为沉淀剂制备钇铕的草酸盐前驱体,然后加入（Na2CO3＋S＋NaCl）复合熔盐在1200 ℃下焙烧2 h即可制得发光强度高出商用粉5%的近球形Y2O3：Eu.     

不同晶型二氧化锰纳米棒催化氧化氯苯性能的研究

采用水热法分别合成了α-, β-, γ-MnO₂纳米棒, 使用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、氢气程序升温还原(H₂-TPR)和X射线光电子能谱(XPS)等技术对三种晶型MnO₂纳米棒的结构和形貌进行了表征, 并以氯苯(CB)为探针考察了其催化活性和稳定性. 结果表明, 三种晶型MnO₂纳米棒在低温范围内均有较高的催化活性, 且活性顺序为α-MnO₂＞γ-MnO₂＞β-MnO₂. 此外, 还发现三种晶型MnO₂纳米棒比无定形MnO₂有更强的抗氯中毒能力. 在三种晶型MnO₂纳米棒中, α-MnO₂纳米棒催化氧化氯苯的活性最佳, 主要是由于该种MnO₂纳米棒含有丰富的晶格氧并且具有较强的可还原能力.     

改性PAN纤维与Fe3+的配位反应及配合物的催化性能

采用盐酸羟胺和水合肼的混合物分别对PAN纤维进行改性制备了偕胺肟改性PAN纤维(AO-PAN)和混合改性PAN纤维(M-PAN), 并分别与Fe³⁺进行配位反应生成两种改性PAN纤维铁配合物(Fe-AO-PAN和Fe-M-PAN). 研究了配位反应的动力学特性及温度和Fe³⁺初始浓度的影响, 并采用DRS和ESR技术比较了两种不同改性PAN纤维铁配合物对偶氮染料活性红195氧化降解反应的催化性能. 结果表明, 在所设定的温度和浓度范围内, 两种改性PAN纤维与Fe³⁺之间的配位反应平衡符合Langmuir 和Freundlich 吸附等温模型以及Lagergren准二级动力学方程, 并且AO-PAN比M-PAN更容易与Fe³⁺发生配位反应. 在相同条件下AO-PAN与Fe³⁺反应的配合量和反应速率常数均比M-PAN与Fe³⁺反应的高. 两种配合物对染料的氧化降解反应具有催化作用, 暗态条件下Fe-M-PAN比Fe-AO-PAN表现出更高的催化活性, 而光辐射条件下Fe-AO-PAN的催化活性显著增强.     

可见光/Fenton光催化降解有机染料

采用Fenton试剂(Fe³⁺/H₂O₂)在可见光条件下(λ＞450nm)光催化降解目标染料化合物罗丹明B(RhodamineB,RhB).在pH＜3.0体系中用可见光照射,能使RhB染料在光敏化作用下有效降解,反应160min后矿化率达到71.8%.采用ESR和溴甲酚绿(Bromocresolgreen,BCG)法跟踪测定活性氧化物种,通过对RhB降解过程的紫外-可见光谱、红外光谱分析及总有机碳量(TOC)跟踪测定,结果表明,Fe³⁺/H₂O₂/RhB体系在可见光照射下主要的活性氧化物种为羟基自由基,能有效地降解RhB.     

Ag/Ag2WO4等离子体共振催化剂可见光催化还原CO2

转化CO₂为有机组分是缓解全球变暖和保障持续能源供给的有效方法之一.采用简易的离子交换结合水合肼还原法制备了一系列不同晶相Ag₂WO₄载银(Ag/Ag₂WO₄)的等离子共振光催化剂,并用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜-能量色散X射线光谱(SEM-EDS)、紫外-可见(UV-Vis)吸收光谱和比表面积测试对催化剂进行了表征.较之Ag₂WO₄, Ag/Ag₂WO₄在可见光催化还原CO₂生成CH₄时显示了明显提高的量子产率(QY)、能量投入产出比(EROEI)、转换数(TON),就Ag/α-Ag₂WO₄, Ag/β-Ag₂WO₄和Ag/γ-Ag₂WO₄而言,最佳催化剂为Ag/β-Ag₂WO₄,其实际最佳Ag:Ag₂WO₄摩尔比为4:96,该催化剂还原CO₂为CH₄的QY、EROEI、TON和拟一级反应速率常数分别为0.145%、0.067%、9.61和1.96×10^-6 min^-1.此外,制备的等离子共振Ag/Ag₂WO₄光催化剂在可见光辐照下进行循环反应仍能保持稳定性.局域表面等离子共振效应是强化Ag/Ag₂WO₄光催化剂活性和稳定性的主要原因.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

探究“铁的锈蚀条件”实验创新设计

设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。