Study of K/Mn-MgO Supported Fe Catalysts with Fe（CO）5 and Fe（NO3）3 as Precursors for CO Hydrogenation to Light Alkenes

Two K/Mn-MgO supported catalysts were prepared by Fe（CO）5 and Fe（NO3）3 as precursor respectively. The obtained Fe-K/Mn-MgO catalysts were tested for CO hydrogenation to light alkenes and characterized by X-ray powder diffraction （XRD）, X-ray photoelectron spectra （XPS）, H2 temperature-programmed reduction （H2-TPR）, H2 CO and CO2 temperature-programmed desorption （H2, CO/CO2-TPD） and transmission electron microscope （TEM） The results indicated that the catalyst with 10 wt% Fe loading prepared by Fe（CO）5 as precursor showed better performance in syngas to light alkenes than ones obtained from Fe（NO3）3 as precursor, where the CO conversion was 62.50% and the selectivity was 55.95% at 350 ℃, 1.5 MPa and 1000 h^-1, respectively.     

Theoretical Studies on Reaction Mechanisms of HNCS with NH （ X^3∑）

The reaction mechanisms of HNCS with NH（X^3∑ ） were theoretically investigated. The minimum energy paths （MEP） of the reaction were calculated by using the density functional theory（DFT） at the B3LYP/6-311 ＋ ＋ G^＊＊ level. The equilibrium structural parameters, the harmonic vibrational frequencies, the total energies, and the zeropoint energies（ZPE） of all the species were calculated. The single-point energies along the MEP were further refined at the QCISD（T）/6-311 ＋ ＋ G^＊ ＊ level. It was found that the mechanisms of the HNCS ＋ NH（X^3∑） reaction involve two channels producing the HNC ＋ HNS and the N2H2 ＋ CS products. Channel 1 plays a dominant role and the HNC ＋ HNS are the main preduets. The reaction is exothermie.     

Studies on the Electronic Structures and Spectra of C78（CH2）3

The structures and spectra of 20 possible isomers of C78(CH2)3 have been studied by using AM1,INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78(CH2)3 (A) with annulene structures,where three -CH2 groups are added to the 6/6 bonds located at the same hexagon passed by the shortest axis of C78 (C2v). Compared with that of C78 (C2v),the first absorption in the electronic spectrum of C78(CH2)3 (A) is blue-shifted because of its wider LUMO-HOMO energy gap. While the IR frequencies of the C–C bonds on the carbon cage are red-shifted owing to the formation of annulene structures and the extension of the conjugated system. The chemical shifts of the carbon atoms in 13C NMR spectra are moved upfield upon the addition.     

Ceric（Ⅳ）-mediated Oxidative Addition of 1, 3-Dicarbonyl Compounds to MCPs： A Facile Access to Dihydrofuran Derivatives Incorporating Cyclopropyl Groups

Alkylidenecyclopropanes undergo ceric（Ⅳ） ammonium nitrate （CAN）-mediated addition reaction with 1,3-dicarbonyl compounds leading to dihydrofuran derivatives incorporating cyclopropyl groups in moderate yields.     

Highly Selective Salicylate Membrane Electrode Based on N,N＇- （Aminoethyl）ethylenediamide Bis（2-salicylideneimine） Binuclear Copper（Ⅱ） Complex as Neutral Carrier

A new ion selective electrode for salicylate based on N,N＇-（aminoethyl）ethylenediamide bis（2-salicylideneimine） binuclear copper（Ⅱ） complex [Cu（Ⅱ）2-AEBS] as an ionophore was developed. The electrode has a linear range from 1.0 × 10^-1 to 5.0 ×10^-7 mol·L^- 1 with a near-Nemstian slope of （ - 55 ±1 ） mV/decade and a detection limit of 2.0 × 10-7 mol·L^-1 in phosphorate buffer solution of pH 5.0 at 25 ℃. It shows good selectivity for Sal^- and displays anti-Hofmeister selectivity sequence： Sal^-〉SCN^-〉 ClO4^- 〉I^-〉 NO2^- 〉Br^-〉 NO3^- 〉Cl^-〉 SO3^2- 〉 SO4^2- The proposed sensor based on binuclear copper（Ⅱ）complex has a fast response time of 5-10 s and can be used for at least 2 months without any major deviation. The response mechanism is discussed in view of the alternating current （AC） impedance technique and the UV-vis spectroscopy technique. The effect of the electrode membrane compositions and the experimental conditions were studied. The electrode has been successfully used for the determination of salicylate ion in drug pharmaceutical preparations.     

A New Supramolecular Compound Based on Cd（II）-Schiff-base and Keggin-type [PMo_（12）O_（40）]~3

A new supramolecular compound, {[Cd(L)2]2[PMo12O40NO3]·CH3CN·2H2O}n 1 (L is 1,4-bis(4-imidazolyl)-2,3-diaza-1,3-butadiene), based on Cd(II)-Schiff-base and Keggin- type [PMo12O40]3- was synthesized via self-assembly and structurally characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction analysis. The crystal is of triclinic, space group P1 with a = 12.0128(11), b = 13.6196(13), c = 13.9995(13) , α = 103.868(2), β = 95.225(2), γ = 101.024(2)°, V = 2160.0(3) 3, Z = 1, C34H39N26O45Cd2Mo12P, Mr = 2938.96, Dc = 2.259 g/cm3, μ = 2.276 mm-1, F(000) = 1400, the final R = 0.0565 and wR = 0.1613 for 4973 observed reflections with I 2σ(I). The crystal structure can be described by the packing of Keggin anionic and Metal-Schiff-base cationic layers.     

Synthesis, Crystal Structure, Antibacterial Activities and Theoretical Computation of 3-（2-Hydroxybenzly）-4-（4-isopropylbenzylideneamino）-（1H）-1,2,4-triazole-5-thione

1INTRODUCTION Recently,compounds containing pyrazole,imida-zole,triazole(including benzotriazole),pyridine,tetrazole and indole have attracted much interest because they exhibit some fungicidal activity,plant-growth regulating activity and antibacterial acti-vity[1～10].Schiff bases also constitute a good type of biologically active substructure[11～14],and the sulfur-containing Schiff bases are particularly effective.Studies of pyrazole Schiff base-type fungicides andtriazole compounds c…     

Interactions with ATP, DNA Cleavage and Anti-tumor Activities of Complexes with Anions [Mo（V）O2（O2CeH4）2]^3-, [Mo（Ⅴ）0.5W（Ⅵ）0.5O2（O2C6H4）2]^2.5- and [W（Ⅵ）O2（O2C6H4）2]^2-

(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands.     

热致液晶含氯侧基聚芳醚酮的单晶状条带织构

通常主链液晶高分子在受到剪切作用时 ,分子微纤呈周期性锯齿状排列 ,其光学效应表现为在偏光显微镜下可观察到相互平行且与剪切方向垂直的条带织构 [1] .而厚度适中的主链液晶聚合物薄膜经过热处理 ,即使没有受到剪切取向的作用 ,介晶微区的尺寸发展到一定大小时也会形成条带织构 ,即所谓结晶诱导[2 ] 和固化诱导 [3,4 ] 的条带织构 .在所报道的条带织构中 (包括剪切和非剪切 ) ,分子链均平行于膜平面 .本文研究发现 ,热致液晶氯代聚芳醚酮的薄膜样品在其高有序液晶温区经热处理 ,可形成结晶诱导的单晶状条带织构 ,其分子链垂直于膜平面 .…     

一种新型聚芳醚酮的热致液晶行为

聚芳醚酮具有优异的耐热性和环境稳定性 ,作为特种工程塑料在宇航、军工等高技术领域得到了广泛的应用 [1 ] .但其熔融温度较高 ,熔体粘度较大 ,在加工中存在一定困难 .热致液晶高分子 ( TLCP)具有较低的粘度 ,复合在热塑性高分子基体中的 TL CP在剪切力或拉伸应变流的作用下发生取向、变形成纤 ,其强度比热塑性基体高 1～ 2个数量级 ,另外 TL CP微纤提供了极大的纤维粘附表面积 ,因此 ,TL CP与聚合物共混具有广阔应用前景 .本文通过联苯二酚、 2 -叔丁基 - 1 ,4-对苯二酚与 4,4′-二氟二苯酮的亲核取代反应合成了一种具有热致液晶性…     

热致性液晶聚合物的种类对液晶/环氧树脂共混物固化反应动力学的影响

采用等温DSC固化动力学研究方法,用自催化动力学模型对反应型热致性液晶聚合物/环氧树脂共混体系进行研究.结果表明,EP/DDS未改性体系,在α＜40%范围遵循自催化反应机理;EP/DDS/LCPU共混改性体系,在α＜60%范围遵循自催化动力学反应机理,而且自催化反应速率和非催化反应速率均大于未改性体系,表明反应型热致性液晶聚合物的活性基团对固化反应起到了催化促进作用;EP/DDS/PHBHT共混改性体系能够较好符合n级反应机理,固化反应的活化能较大,说明没有反应基团的液晶聚合物(PHBHT)对固化反应无明显促进作用.     

聚芳醚酮与液晶聚酯多嵌段共聚物的合成表征

近年来,以热塑性聚合物为基体,热致液晶聚合物(TLCP)作为增强剂的高分子原位复合材料由于其具有优异的机械性能和优良的成型加工性能,已引起各国工作者的普遍关注和极大兴趣．然而由于自聚集和相分离作用的影响,大部分液晶聚合物与通常的热塑性聚合物基体基本不相容或弱相容,这对于提高原位复合材料的力学性能不利．     

The Rheological and Extrusion Behaviour of Blends Based on Phenolphthalein Poly(ether-ether-sulfone) and Thermotropic Liquid Crystalline Polymer

ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｅｌａｓｔｔｗｏｄｅｃａｄｅｓ，ｐａｒｔｉｃｕｌａｒａｔｅｎｔｉｏｎｈａｓｂｅｅｎｄｅｖｏｔｅｄｔｏｕｓｉｎｇｔｈｅｔｈｅｒｍｏｔｒｏｐｉｃｌｉｑｕｉｄｃｒｙｓｔａｌｉｎｅｐｏｌｙｍｅｒｓ（ＴＬＣＰ）ａｓａｒｅｉｎｆｏ...     

分子量对壳聚糖溶致液晶性的影响

三种不同分子量的壳聚糖[脱乙酰度均为(84±1)%]在二氯乙酸溶液中都呈现胆甾型溶致液晶相.临界浓度随分子量增加而降低,但均比同样聚合度的甲壳素的高.用偏光显微镜法和激光小角散射法测得的胆甾液晶相的螺距很相近,在浓度相同时,其值随分子量的增加而减小.     

Dynamic Rheological Characterization of A Thermotropic Liquid Crystalline Poly (aryl ether ketone)

Poly(aryl ether ketone)s (PAEKs) have been widely used as advanced materials in applications because of their excellent thermal stabilities and good chemical resistance1. The high melt viscosity is one of the major drawbacks in processing them. The synthesis of thermotropic liquid crystalline PAEKs has shed light on the solving of this problem2 because they have been proved to have melt viscosities significantly lower in nematic state than those of the isotropic PAEKs and can be melt proce…     

含不同柔性链的(甲基)丙烯酸酯类液晶高分子的合成及其液晶行为研究

通过改变侧链中柔性间隔基的长度,合成了一系列含有两个手性中心的侧链液晶（甲基）丙烯酸酯类聚合物.红外、核磁和GPC表征各中间体、单体及聚合物的结构和分子量.通过DSC和热台偏光显微镜系统地研究了单体和聚合物的液晶态织构.结果表明,含有六个碳的柔性间隔基的丙烯酸酯类聚合物表现为近晶SA和手性近晶SC^＊液晶相.     

基于“甲壳”效应、不同尾链长度的离子液晶高分子的相行为和相结构

考察了一系列基于"甲壳"效应的离子液晶高分子poly(2,5-bis{[6-(4-butoxy-4?-imidazolium phenyl)k-alkyl]oxy carbonyl}styrene bis(fluoroborate)salts)Pk-6-BF4(k=4,8,12,16)的相行为和相结构.热重分析结果表明,该系列聚合物的热分解温度都在320?C以上,说明其均具有优异的热稳定性能.示差扫描量热仪结果表明,P4-6-BF4和P8-6-BF4仅表现出一个玻璃化转变,随着尾链的增长,P12-6-BF4和P16-6-BF4具有一个结晶熔融峰.偏光显微镜、一维广角X衍射、二维广角X衍射结果表明,该系列聚合物均形成稳定的近晶A相结构,并且随着烷烃尾链的增长,层间距增加、近晶结构内部分子堆积形式有所改变.     

聚酯醚液晶弹性体的相行为与力学性能

用热台偏光显微镜、差示扫描量热仪、广角Ｘ－射线衍射仪和单纤维电子强力仪对一类新型的聚酯醚液晶弹性体的相行为与力学性能进行了研究。讨论了共聚物性能同硬段含量的关系。研究表明这类嵌段共物由于产生微相分离而兼具橡胶弹性和热致液晶性,它们的拉伸强度为１０～４２ＭＰａ,弹性模量为５～３０ＭＰａ,断裂伸长率为２００～３２０％。