用三异辛氧基混合稀土改性聚苯乙烯的研究

通过原位本体聚合制备三异辛氧基混合稀土改性的聚苯乙烯，采用FT－IR，UV，FS和DMTA等手段研究三异辛氧基混合稀土对PS性能的影响，并测定其冲击强度。结果表明，改性PS的荧光强度随稀土含量的增加而提高；DMTA表明改性PS的玻璃化温度比纯PS的低，同时改性PS在低温－85度左右有一个较大的β转变峰，冲击强度亦有明显提高，说明改性PS具有较好的低温抗冲击性能。     

三异丁氧基混合稀土增韧聚苯乙烯的研究

通过原位本体聚合制备三异丁氧基混合稀土掺杂聚苯乙烯 ,采用FT IR、UV Vis、FS和DMTA等对其表征 ,并测定其冲击强度 .表明改性聚苯乙烯中存在着稀土金属离子和苯环的配位作用 ,改性聚苯乙烯的玻璃化温度随稀土含量增加而下降 ,但其抗冲性能显著提高 .说明三异丁氧基混合稀土对聚苯乙烯有明显的增韧改性作用     

恒电位电解法制备光致发光掺钬多孔硅

研究了一种新的多孔硅掺稀土的电化学方法———恒电位电解，以及稀土硝酸盐支持电解质有机溶剂的新电解体系。这一方法和体系的特点是通过采用适当外加电压来控制电解产物，提高掺入的稀土浓度，提高发光强度，同时避免生成导致发光不稳定的产物，提高发光稳定性。优化了阳极氧化制备多孔硅的条件和阴极还原制备掺钬多孔硅的条件（钬化合物浓度、溶剂、离子强度、电解电压、时间），获得光致发光强度高于多孔硅的掺钬多孔硅。对多孔硅和掺钬多孔硅的光致发光机制进行了讨论。     

注塑工艺对高抗冲聚苯乙烯力学性能的影响

通过正交实验和单因素变量实验研究了射胶压力、射胶速度、保压压力、保压时间和冷却时间对高抗冲聚苯乙烯缺口冲击强度、弯曲强度、弯曲模量、拉伸屈服应力等力学性能的影响。结果表明,射胶速度、保压时间和冷却时间对高抗冲聚苯乙烯力学性能影响较小,而射胶压力、保压压力对高抗冲聚苯乙烯力学性能有显著影响,特别是缺口冲击强度和拉伸屈服应力。     

接枝共聚物氯化聚乙烯－苯乙烯对聚苯乙烯的共混改性

用氯化聚乙烯接枝苯乙烯共聚物（ＣＰＥ－ｇ－Ｓｔ）和氯比聚乙烯（ＣＰＥ）对聚苯乙烯（ＰＳ）进行共混改性．当ＣＰＥ含量为２５％时，用ＣＰＥ－ｇ－Ｓｔ改性的共混物的冲击强度为１８．５ｋＪ·ｍ￣（－２），是用ＣＰＥ改性的共混物冲击强度的２．１倍；其拉伸强度不低于３４ＭＰａ．     

三异丙氧基混合稀土掺杂改性聚苯乙烯的研究

用廉价的三异丙氧基混合稀土杂改性聚苯乙烯，利用红外光谱，紫外与可见光吸收光谱，荧光光谱，X射线光电子能谱，扫描电镜等手段对其表下，并测定其冲击强度。证明了改性聚苯乙烯中存在着稀土金属离子与苯环的配位作用；改性聚苯乙烯的荧光强度比纯聚苯乙烯的高，其中以稀土含量为1．0％时其荧光强度最高，同时改性后聚苯乙烯抗冲性能显著提高，表明三异丙氧基混合稀土对聚苯乙烯有较好的增韧作用。     

接枝共聚物氯化聚乙烯—苯乙烯对聚苯乙烯的共混改性

用氯化聚乙烯接枝苯乙烯共聚物（ＣＰＥ－ｇ－Ｓｔ）和氯化聚乙烯（ＣＰＥ）对聚苯乙烯（ＰＳ）进行共混改性。当ＣＰＥ含量为２５％时，用ＣＰＥ－ｇＳｔ改性的共混物的冲击强度为１８．５ｋＪ．ｍ＾－＾２，是用ＣＰＥ改性的共混物冲击强度的２．１倍；其拉伸强度不低于３４ＭＰａ。     

稀土掺杂LaOCl粉末样品的多次漫反射光谱及量子效率计算

测量了ＬａＯＣｌ：Ｅｒ，ＬａＯＣｌ：Ｈｏ粉末样品的多次漫反射光谱、激光光谱、发射光谱及相应反射的弛豫时间。由多次漫反射光谱得到漫反射吸收光谱。根据Ｊｕｄｄ－Ｏｆｅｌｔ理论计算了强度参数、辐射跃迁几率及最子效率。并与掺铒及钬的氟玻璃、氧化物玻璃及其他基质相比较。     

PLA/MWNTs/HA复合材料的制备和性能研究

采用超声辅助原位湿法合成多壁碳纳米管／羟基磷灰石纳米复合材料(MWNTs／HA),并通过溶液浇铸法制备了PLA／MWNTs／HA复合材料薄膜。考察了MWNTs／HA纳米粒子含量对复合膜性能的影响,并通过力学性能、SEM、FTIR、以及DMTA对复合膜性能进行了表征,结果表明：随着纳米粒子质量分数的增加,复合膜的拉伸强度呈下降趋势;拉伸模量和储能模量呈现先下降后上升的趋势;玻璃化转变温度则呈现不断上升趋势。     

新型sPS/PA6/SsPS-H塑料合金的性能和形态结构

研究新型sPS PA6 SsPS H塑料合金的力学性能和微观形态结构 .间规聚苯乙烯 (sPS)的磺化产物磺化间规聚苯乙烯 (SsPS H)的加入明显地改善了sPS PA6(聚酰胺 6)二组分合金的力学性能 ,在sPS PA6 SsPS H重量组成为 80 2 0 5时 ,三组分合金的冲击强度最大 ,为 1 5 6kJ m2 ,约为纯sPS冲击强度的 3倍 DMA和SEM结果表明 ,SsPS H对sPS和PA6共混有良好的增容作用 ,它起到了降低合金的微相尺寸和加强相间界面粘结的作用 .此外 ,FTIR结果还表明SsPS H和PA6之间存在特殊相互作用 ,其作用方式是通过SsPS H的磺酸基将其质子转移给PA6酰胺基的氮     

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

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.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.