从猪、羊蹄壳中土法提取貴重藥品——酪氨酸

L-酪氨酸(分子量181.19,含氮量7.7％,分子式C_6H_4.OH.CH_2.GH.NH_2.GOOH)是一种动植物蛋白貭經酸分解后的产物。在猪、羊蹄壳,毛髮及蚕蛹內均含有酪氨酸。利用土法提取酪氨酸使用的范品、仪器簡单,并在1000克猪(或羊)蹄壳中能提出約25克左右的酪氨酸。酪氨酸为白色有光泽的針状結晶,有时成一束,貭較輕,难溶于冷水但能溶于沸水,也能溶于稀酸、稀碱、液态氨中,微溶于酒精,但不溶于醚。熔点314—318℃,同时分解。[d]_D~(20)—8.64°(20％盐酸溶液)。     

工业用Ni／Al2O3催化剂的再生

工业用Ｎｉ／Ａｌ_２Ｏ_３催化剂的再生徐国林，史克英，商永臣，范业梅，徐恒泳（哈尔滨师范大学化学系哈尔滨１５００８０）关键词矾土负载镍，催化剂，合成气，再生镍负载型催化剂在化学工业上具有极其广泛的用途，本文提出了这类催化剂再生过程中活性物种的疏活作用，...     

配位体 SO_4~(2-)对激发态铀(Ⅵ)去活化的影响

近年来,随着激光、微弱信号测量以及瞬态测量技术等发展,对溶液中激发态离子的化学和物理行为的研究已日益受到人们的重视,激发态铀酰离子发光衰减的研究尤为活跃.Marcantonatos 等、Formosinho 等以及郑企克、王志麟等对高氯酸溶液中激发态铀酰离子的发光衰减过程进行了详细的研究.探讨了ClO_4~-溶液中pH 等对激发态铀酰离子的发光衰减的影响,观察到了一定的pH 条件下激发态铀(Ⅵ)的非单一指数衰减,并各自提出了不同的解释.值得提出的是,上述的一系列研究都是在高氯酸溶液中,其它体系中铀(Ⅵ)的发光哀减的研究进行得很少,报导则更少.1983年Joshi 等曾研究了80K 时SO_4~(2-)     

波蘭在高分子化合物方面的科學工作

1955年末,蘇聯科學院元素有機化合物研究所的教授應波蘭科學院的邀請,到波蘭作了两星期的訪问,目的是了解波蘭科學家在高分子化合物方面的科學工作情况,並介紹蘇聯在這領域中的研究工作。 教授訪問了華沙、洛茲及霍日夫等三個城市的許多科學機關和高等學校,並參觀了霍日夫的聚酰胺纖維工廠及奥斯威辛的化學聯合工廠。     

Synthesis and Antifungal Activity of Novel Chiral α-Aminophosphonates Containing Fluorine Moiety

Chiral α-aminophosphonates were synthesized using （R） or （S）-1-phenylethylamine in the presence of BF3·Et2O under microwave irradiation in moderate to good yields. The new compounds were identified by ^1H NMR, ^19F NMR, IR and elemental analysis. Their antifungal activities were evaluated and some compounds were found to exhibit excellent antifungal activities. To the best of our knowledge, this is the first report on antifungal activity of chiral α-aminophosphonates containing fluorine moiety.     

噻唑偶氮衍生物与铋的显色反应的研究

光度法是测定物料中微量铋的灵敏方法。经典的分光光度法灵敏度很低而不能满足需要。近期发展的铋与DBDTC、磺基萤光酮、邻苯二酚紫、甲基百里酚蓝、ДБФФ等三元配合物体系,灵敏度均属中等,其中只有ДБФФ在CPC存在下是高灵敏的(ε=1.1×10~5)。因此研究铋的新的高灵敏显色剂是有意义的。Саввин等曾合成以4,5-二甲基噻唑为母体的显色剂,但与金属离子反应的灵敏度不高。用我们首次合成的2-(4,5-二甲基噻唑-2-偶氮)-5-二乙氨基苯酚(DMTAE)为试剂(简称H_nR),可明显地提高试剂与金属离子铋(Ⅲ)、镓(Ⅲ)、镉(Ⅱ)等显色反应的灵敏度。在30％乙醇水溶液中或在表面活性剂的胶束增溶作用下,铋的摩尔吸光度达10~5数量级。本文详细     

THE CRYSTAL STRUCTURE OF BAYLEYITE

The bayleyite crystallizes in monoclinic space group C_2~5h-P2_1/c with a=6.499(1), b=15.235(5), c=26.513(6), β= 92.92(2)°, Z=4. Intensities of 3430 independent reflections are collected with diffractometer using MoKα radiation. The crystal structure has been solved by the Patterson method and refined by block least square refinement for positional parameters and isotropic temperature factor of non-hydrogen atoms. The final R factor is 0.038.The result of crystal structure analysis shows that the structure consists of discrete [UO_2(CO_3)_3]~(4-) ions and Mg~(2 ) cations are between slab-like units, but they are not in a slablike unit. Its crystal struture is different from that of liebigite which was determined by Appleman. Complexes and cations between slab-like units and in a slab-like unit are connected by hydrogen bonds formed by water molecules.     

LOW-TEMPERATURE HEAT CAPACITIES AND THERMODYNAMIC PROPERTIES OF LANTHANUM AND CERIUM TRIISOTHIOCYANATE HYDRATESI (Ⅰ)——La(NCS)_3, 7H_2O AND Ce(NCS)_3. 7H_2O

The heat capacities of La(NCS)_3. 7H_2O and Ce(NCS)_3. 7H_2O have been measured from 13 to 300K with a fully-automated adiabatic calorimeter. The construction and procedures of the calorimetric system are described in detail. No obvious thermal anomaly was observed for both compounds in the experimental temperature range. The polynomial equations for calculating the heat capacity values of the two compounds in the range 13—300K were obtained by the least-squares fitting based on the experimental C_p data. The C_p values below 13K were estimated by using the Debye and Einstein heat Capacity functions. The standard molar thermodynamic functions were calculated from 0 to 300K. Gibbs energies of formation were also calculated.     

稀土元素在6063合金中的分布及其作用机理

用金相观察、扫描电镜的波谱和能谱分析结果表明,稀土在6063铝合金铸态组织中富集于晶界,稀土促进了Si和Fe向晶界偏聚,减少了针状铁相,铸态组织均匀、细化,强度提高。过量稀土会形成Al—La类稀土夹杂物,分布在晶界和晶内,使铸态组织粗化,合金强度下降。含稀土的铝合金型材中铁相有所细化,稀土化合物呈球团状,强度及硬度有所提高。