水热法合成一维硒纳米材料及其力学性能分析

采用环境友好的一步水热法,以Ge Se4玻璃为原料,水溶液为反应介质,在80℃合成三方相硒(t-Se)一维纳米结构。用透射电子显微镜(TEM)、拉曼光谱(Raman)、扫描电子显微镜(SEM)、原子力显微镜(AFM)等手段表征了一维Se纳米纤维的形貌和结构。结果表明,合成的Se纤维沿t-Se的[001]方向生长,截面为六边形。反应144 h后,纤维长度达到毫米级,平均直径为1~5μm。对合成的Se纤维进行纳米压痕实验,测得其硬度和弹性模量分别为(399.5±20.4)MPa和(1.13±0.05)GPa。在p H=12.0的Na OH溶液(80℃)中,Se纳米纤维生长速度高于酸性(p H=3.3)和中性(p H=6.3)介质,反应24 h后,纤维平均长度和直径达到344和1.12μm。     

(Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05) O4+δ纳米纤维阴极的制备及电化学性质

采用静电纺丝法制备了（Pr_0.9La_0.1）₂（Ni_0.74Cu_0.21Ga_0.05）O_4+δ（PLNCG）氧化物纳米纤维。利用热重-差热分析（TG-DTA）、X射线衍射（XRD）、傅里叶变换红外光谱（FT-IR）和扫描电子显微镜（SEM）对材料的物相及微观形貌进行分析。研究表明950℃煅烧5 h得到平均直径420 nm、形貌均一的PLNCG氧化物纤维;1 000℃烧结2 h得到紧密附着在Ce_0.9Gd_0.1O_2-δ（CGO）电解质上的网状结构纤维阴极。电化学阻抗谱（EIS）测试结果表明纳米纤维阴极具有比粉体阴极更优越的性能。700℃的极化电阻（R_P）为0.134 Ω·cm²,比同组分的粉末阴极减少32%（R_P=0.197 Ω·cm²）。以纤维阴极构筑的电解质支撑单电池Ni-CGO/CGO/PLNCG在700℃的最大输出功率密度为231 mW·cm^-2。氧分压测试结果表明阴极反应的速率控制步骤为电荷转移过程。     

一维Bi2Fe4O9纳米棒阵列的无模板水热合成

以物质的量的比为1：1的Bi（NO₃）₃·5H₂O和Fe（NO₃）₃·9H₂O为反应原料,以NaOH为矿化剂,利用水热法在Ti基板上成功制备出一维Bi₂Fe₄O₉纳米棒阵列。对该纳米棒阵列分别进行XRD、FE-SEM、HR-TEM和UV-Vis测试,得到Bi₂Fe₄O₉纳米棒的直径为100nm,长度为3~4μm,并表现出良好的光吸收性能,禁带宽度约为1.9eV,对甲基紫溶液的光降解率达到86%,其活性明显高于市售P25（TiO₂）。该纳米棒阵列的生长方式完全遵循奥斯瓦尔德熟化（Ostwald ripening）单晶生长机理。     

静电纺丝法制备纳米氧化铟锡及其导电性能

采用静电纺丝-溶胶凝胶法,以SnCl₂、InCl₃、聚乙烯吡咯烷酮（PVP）等为原料,乙醇胺为水解控制剂,合成了超细氧化铟锡（ITO）纳米纤维及富氧缺陷的ITO纳米颗粒。采用透射电子显微镜（TEM）、选区电子衍射（SAED）、扫描电子显微镜（SEM）、热重分析（TGA）、X射线衍射（XRD）、X射线电子能谱（XPS）、四探针电阻仪,系统研究了超细ITO纤维及颗粒的形貌、晶型、氧缺陷及导电性能。在400℃空气煅烧后,纤维中的PVP高分子骨架发生热分解,获得超细、多孔ITO纳米纤维,晶型为立方相。进一步升高煅烧温度至800℃,ITO纳米纤维转变为富氧缺陷的纳米颗粒,晶格氧空位含量高达38.9%。随着煅烧温度升高,Sn⁴⁺掺入到In₂O₃晶格中,发生晶格膨胀,晶面间距增大。煅烧温度由400℃升高至800℃,未发生立方相向六方相的转变,晶型稳定,晶粒尺寸从32 nm生长到44 nm,晶格应变（ε₀）从1.42×10^-2减小至1.04×10^-2,应变诱导的晶格弛豫逐渐减小。此外,高温煅烧可抑制In₂O₃晶粒（111）晶面的增长,随着In₂O₃的（400）与（222）晶面比值（I_（400）/I_（222））的增加,ITO电导率逐渐升高。在800℃获得的ITO纳米晶粒导电率最高。     

室温一步固相反应合成纳米氧化锌的表征、光催化性能及动力学

以七水硫酸锌、氢氧化钠为原料,采用室温一步固相反应合成ZnO纳米粒子,并分别利用X射线衍射分析（XRD）、傅里叶变换红外光谱分析（FTIR）、热重分析（TG）、扫描电子显微分析（SEM）、透射电子显微分析（TEM）、N₂吸附-脱附、紫外可见漫反射光谱分析（UV-Vis DRS）等方法对ZnO纳米粒子进行表征。实验结果表明：不需任何添加剂,室温下可通过一步固相反应合成ZnO纳米粒子,其形成过程首先是ZnSO₄·7H₂O和NaOH充分接触,然后反应形成Zn₄SO₄（OH）₆·5H₂O,最后NaOH的溶解热可使Zn₄SO₄（OH）₆·5H₂O转变为ZnO并逐渐长大形成纳米粒子。同时以甲基橙为降解对象评价了ZnO纳米粒子的光催化活性,实验结果表明：紫外光照射下,该方法合成的ZnO纳米粒子对甲基橙具有较好的光催化活性,且光催化动力学方程符合准一级反应动力学。     

ZnIn2S4/Au纳米片阵列的制备及其可见光响应光电化学固氮特性

采用简单的水热法合成出单晶ZnIn₂S₄纳米片阵列以实现可见光响应光电化学固氮。并采用光沉积法将超细Au纳米颗粒（5 nm）沉积于ZnIn₂S₄纳米片的棱角位置处,实现了可见光俘获和载流子分离能力的同时增强。当负载合适含量的Au纳米颗粒,ZnIn₂S₄纳米片阵列的光电固氮活性由1.092 μg·cm^-2·h^-1提升至2.262 μg·cm^-2·h^-1。我们还提出一个简单模型用以阐明其性能增强机制,这也被光致发光（PL）谱和光电化学（PEC）性能结果所证实。     

玫瑰花状氢氧化钴的结构和浸润性研究

在没有任何表面活性剂条件下,通过简单的方法首次合成了玫瑰花状β-Co(OH)₂微晶。玫瑰花状β-Co(OH)₂微晶宽3~5 μm,厚2~3 μm,是由平均厚度为15 nm的纳米片所组成。玫瑰花状β-Co(OH)₂组成的薄膜的接触角为158.5°±1.2°,表面处于任意的角度,水滴都不会滴落。     

基于Ni12P5纳米粒子的电化学传感器用于灵敏测定葡萄糖

通过改进的热溶剂胶体合成法制备了单分散的Ni₁₂P₅纳米粒子,并利用X射线衍射、透射电子显微镜、X射线光电子能谱、X射线能谱对Ni₁₂P₅纳米粒子的晶体结构、化学组成和形貌等进行了表征。基于单分散Ni₁₂P₅纳米粒子研制出的非酶葡萄糖传感器具有出色的性能,其快速响应时间小于3 s,检测范围广（0.002~4.2 mmol·L^-1）,灵敏度高达1 572 mA·L·mol^-1·cm^-2,检测限低至0.8 μmol·L^-1。此外,该传感器在用于人体血液中葡萄糖的实际检测中取得了满意的效果。     

高氮含能配合物M（ATZ）（bpy）m·nH2O液相生成反应的热动力学

合成了6种固态高氮含能配合物M（ATZ）（bpy）m·nH2O（（1）M=Mn,m=2,n=3;（2）M=Co,m=2,n=7;（3）M=Ni,m=2,n=0;（4）M=Cu,m=1,n=0;（5）M=Pb,m=1,n=3;（6）M=Zn,m=1,n=1;ATZ=5,5′-偶氮四唑,bpy=2,2′-联吡啶）。对它们的结构和性能进行了表征。用RD496-CK2000微热量计测定了298.15 K下各配合物的液相生成反应焓变分别为：ΔrHm^θ（1）=241.245±0.060 kJ/mol,ΔrHm^θ（2）=-256.875±0.050 kJ/mol,ΔrHm^θ（3）=-265.172±0.038 kJ/mol,ΔrHm^θ（4）=-236.538±0.038 kJ/mol,ΔrH^θm（5）=-249.698±0.038 kJ/mol,ΔrHm^θ（6）=-185.072±0.048 kJ/mol。通过试验测定得到的所有液相反应的ΔrHm^θ均为负值,有利于目标物生成;并改变反应温度,研究了它们的液相生成反应的热动力学。改变温度研究了液相生成反应的热动力学,利用反应热化学数据和动力学方程结合热动力学实验数据计算了活化焓（ΔH≠^θ）、活化熵（ΔS≠^θ）、活化自由能（ΔG≠^θ）、表观反应速率常数（k）、表观活化能（E）、指前常数（A）和反应级数（n）。     

不同形貌纳米CoWO4的水热法制备及气敏性能

以Co（NO₃）₂·6H₂O、Na₂WO₄·2H₂O为主要原料,去离子水为溶剂,利用水热法在不同条件下制备了一系列的纳米CoWO₄,用XRD、TEM和比表面分析仪对产品的物相、形貌和比表面积进行了表征。较系统地探讨了水热条件（反应混合物pH值、反应时间、反应温度等）对产物物相和形貌的影响,并研究了不同形貌产品对甲醛、乙醇、氨气、苯和丙酮等的敏感性能。结果表明：水热条件对产品的物相和形貌有影响,在不同水热条件下,可成功制备CoWO₄纳米颗粒、纳米立方体及纳米棒;以纳米颗粒、纳米立方体及纳米棒样品制成的气敏元件对被试气体有不同程度的响应,其中以纳米颗粒为基的元件在210℃对1000μL·L^-1NH₃灵敏度为3.3。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.