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991.
The fatty acid composition of tobacco seed oil revealed that the oil is rich in unsaturated fatty acids, having linoleic acid (71.63%), oleic acid (13.46%) and palmitic acid (8.72%) as the most abundant unsaturated and saturated fatty acids respectively. So the tobacco oil was characterized as semi-drying type on the basis of fatty acid composition. The synthesis of alkyd resin was carried out by alcoholysis or monoglyceride process using an alkali refined tobacco seed oil, pentaerythritol, cis-1,2,3,6-tetrahydrophthalic anhydride along with lithium hydroxide as catalyst. The alkyd resin so prepared was found to be bright and of low color with high gloss. The drying and hardness properties and adhesion of the tobacco seed oil derived alkyd resin were also found a bit superior to those of other alkyd resins of the same oil length. In addition, the water and acid resistance of the said alkyd was also found comparable to the other alkyds. 相似文献
992.
PAUNPASSANAN Dechprasitthichoke SUNANTA Wangkarn SAKDIPHON Thiansem PONLAYUTH Sooksamiti ORN-ANONG Arquero 《中国化学》2007,25(9):1229-1232
Characterization of planting materials used as adsorbent has been studied in order to compare potassium ion adsorption on two types of planting materials, which are a fired planting material (FPM) made from a mixture of 4 kinds of wastes (bottom ash, flue gas desulfurization (FGD) gypsum, paddy soil and sawdust) formed and fired at 850 ℃and the commercial planting material called "hydroball" (HDB) bought from Jatujak market, Bangkok. The physical characteristics of both types of planting materials indicate that the FPM has a larger specific surface area than the HDB. The factors affecting potassium adsorption on both the planting materials such as an equilibration time and some solid/solution ratios were investigated. The suitable equilibration time for the adsorption to reach an equilibrium on the FPM and HDB is one and two hours, respectively. The highest amounts of potassium ion adsorbed on both the planting materials were obtained when the solid/solution ratio was 1 : 15. The adsorption behavior on both the planting materials tends to correspond with the Freundlich isotherm. 相似文献
993.
An environmentally benign oxygenation protocol was developed for selective oxidation of some types of aromatic and aliphatic sulfides in good to excellent yields utilizing 34% hydrogen peroxide catalyzed by simple heteropolyoxometalates in normal drinking water at room temperature. The catalysts could be recovered and reused for at least seven reaction cycles under the described reaction conditions without considerable loss of reactivity. This procedure introduced a new insight into the use of simple heteropolyanions as recoverable catalysts for the oxidation of organic sulfides by an environmentally acceptable protocol. Keywords 相似文献
994.
The reactions of dilithium salt of trans-1,2-bis(trimethylsilylamino)cyclohexane with anhydrous lanthanide trichlorides LnCl3 (Ln = Yb, Nd) in THF afforded the dianionic binuclear tricycles of lanthanide chlorides {Li(THF)3[LnCl(μ2-trans-1,2-(NSiMe3)2C6H10)(μ2-Cl)]}2·2THF (Ln=Yb 1, Nd 2) in moderate yields. Both of the bridged complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Crystal structural analysis shows that the two complexes are the analogues which have a tricyclic framework built by two bridged lanthanide metals, four nitrogens and four carbons from two diamide ligands. Each lanthanide metal coordinates to three nitrogen atoms and two chlorines to form a distorted trigonal bipyramid and connects with a lithium by a bridging chlorine. 相似文献
995.
IIB族金属二硫代氨基甲酸配合物的合成、表征及热稳定性研究 总被引:1,自引:0,他引:1
在甲醇溶液中合成了一系列IIB过渡金属Zn(Ⅱ),Cd(Ⅱ)的二羟乙基二硫代氨基甲酸[(EtOH)2dtc]的配合物,并对配合物M[(EtOH)2dtc]2L[M=Zn(1),Cd(2),L=2,2'-联吡啶;M=Zn(3),Cd(4),L=邻菲哕啉]进行了红外光谱、元素分析、热重分析表征工作.热重分析表明配合物1~4中DTC配体比中性配体更易失去,热分解最终产物为相应的氧化物.对化合物1,2做了X-ray单晶衍射分析,1为单斜晶系,P21/c空间群,晶胞参数a=0.72146(5)nm,b=2.61720(18)nm,c=1.59438(11)nm,β=97.899(2)°,V=2.9820(4)nm3,Z=4,μ=1.133mn-1,Dc=1.297Mg·m-3;2为三斜晶系,P-1空间群,晶胞参数a=1.0075(2)am,b=1.1580(2)nm,c=1.1777(2)nm,α=70.92(3)°,β=85.71(3)°,y=81.02(3)°,y=1.2822(4)nm 3,Z=2,μ=2.118mm-1,Dc=1.630Mg·m-3. 相似文献
996.
合成并表征了一个新的Ru(II)配合物[Ru(bpy)2(hedppc)](ClO4)2 {bpy=2,2'-联吡啶, hedppc=二联吡啶[3,2-a: 2',3'-c]吩嗪-11-羧酸(2-羟乙基)酯}. 通过紫外-可见吸收光谱、与溴化乙锭竞争实验、粘度测量和DNA裂解实验研究了配合物与小牛胸腺DNA的相互作用性质. 结果表明配合物以插入模式与DNA键合,键合常数Kb=(6.99±1.34)×106 mol-1•L (s=2.03±0.04)与母体配合物[Ru(bpy)2 (dppz)]2+相近,但光致发光和溶剂变色等光学性质与[Ru(bpy)2 (dppz)]2+有明显的差别. 相似文献
997.
利用一步共还原法在导电高分子聚二氧乙基噻吩/聚对苯乙烯磺酸(PEDOT/PSS)水溶液中合成了磁性纳米复合物Pt3Co-PEDOT/PSS. 利用透射电镜(TEM)、X射线衍射(XRD)、拉曼光谱、超导量子干涉仪(SQUID)对其进行了表征.结果表明Pt3Co纳米粒子为面心立方结构(fcc), 粒子平均粒径为9.6 nm, 标准偏差为2.4 nm. 用旋转涂膜法制备的Pt3Co-PEDOT/PSS薄膜导电率()在1.6~4.0 S/cm之间. 当温度在阻塞温度(TB, 110.5 K)以上时, 纳米复合物Pt3Co-PEDOT/PSS显示出超顺磁性, 低于TB时呈铁磁性, 在5 K时其剩磁(Mr)和矫玩力(Hc)分别为4.1 emu/g和701 Oe(奥斯特). 相似文献
998.
999.
核-壳结构Pd-CoO@SiO催化剂的低浓度甲烷催化燃烧性能 《燃料化学学报》2015,43(9):1120-1127
用自组装法制备了一种具有核–壳结构的Pd-Co3O4@SiO2催化剂,对其低浓度甲烷催化燃烧性能进行了研究。TEM、XRD、H2-TPR表征及催化活性测试结果表明,SiO2壳内的PdO与CoOx之间的强相互作用,使得Pd-Co3O4@SiO2对低浓度甲烷燃烧具有优异的催化活性。同时,与负载型Pd/Co3O4-SiO2及Pd/Co3O4@SiO2催化剂相比,核-壳型Pd-Co3O4@SiO2催化剂经800 ℃煅烧后仍能保持较好的核-壳结构,有效地避免了Pd和Co活性物种的高温烧结,因而具有更高的热稳定性。 相似文献
1000.
The principle of wavelength demultiplexing with multiple volume holographic grating filter is described. The selectivity of its wavelength and angle is analyzed and the wavelength spacing is discussed. One scheme of wavelength demultiplexing with multiple volume holographic grating filter and the technique difficulties to be resolved while being put into practice are put forward. 相似文献