糖蛋白/胆红素钙水溶性复合物的形成及光谱研究

采用傅立叶变换红外光谱(FT-IR)，结合减法、二阶导、退卷积和曲线拟合等先进光谱技术，紫外可见光谱，ICP-AES分析方法，对不同质量比的α-酸性糖蛋白(AGP)和胆红素钙(CaBR)反应后的滤液进行了研究。结果表明，AGP和CaBR之间存在着较强的相互作用，导致AGP二级结构的有序性增加，CaBR的水溶性增大，两者形成了可溶性的AGP/CaBR复合物。     

Increase of Calcium Levels at Interphase in NIH 3T3 Cells

The fluorescent calcium ion indicator dye Fluo-3 and DNA-binding dye Hoechst 33342 were employed to determine, in a quantitative microspectrofluorometric study, the intracellular calcium ion concentration ([Ca~(2+)]_i) and the DNA content of individual living NIH3T3 cells. The well-separated excitation and emission properties of these dyes allowed us to establish for each cell both the phase of the cell cycle using DNA content and [Ca~(2+)]_i. We found that the transition from G_1, through S, to the G_2 phase is accompanied by a two-fold increase in [Ca~(2+)]_i. The [Ca~(2+)]_i was inhomologous in each phase of the interphase (G_1, S and G_2) although [Ca~(2+)]_i in the S and G_2 phases was never lower than certain threshold values in the G_1 and S phases respectively. [Ca~(2+)]_i in G_0 cells was lower than that in G_2 cells. These changes in [Ca~(2+)]_i suggest that [Ca~(2+)]_i may be an import regulator of cell cycle progression.     

阿托伐他汀钙与β-环糊精相互作用的研究及应用

采用线性扫描伏安法和循环伏安法并结合紫外分光光度法研究了新型抗血脂紊乱药物阿托伐他汀钙(AC)与β-环糊精(-βCD)的相互作用.探讨了-βCD对AC的峰电流及AC对-βCD吸附峰电流的影响,测得在0.06mol/LKH2PO4-Na2HPO4(pH=7.17)缓冲溶液中,AC与-βCD包结比为1:1,用电流法测得包结物的形成常数为9.09×104L/mol.根据碱性介质条件下β-CD分子与AC形成包结物而使β-CD吸附峰电流减小的特性,建立了一种利用β-CD间接测定AC的伏安方法.     

电流密度对钙磷沉积层组成和结构的影响(英文)

用X射线衍射、激光拉曼光谱以及等离子体原子发射光谱等技术研究了电化学沉积钙磷陶瓷过程中 ,电流密度对电沉积层组成和结构的影响 .实验表明阴极表面得到的沉积物是几种钙磷盐组成的混合物 ,且其成份随电流密度的改变而发生较大的变化 .在电解液温度为 75℃条件下 ,当控制电流密度较低时 ,沉积层主要由CaHPO4· 2H2 O (DCPD)和Ca8H2 (PO4) 6· 5H2 O (OCP)组成 ;随着电流密度的增加 ,阴极表面逐渐生成Ca3 (PO4) 2 ·nH2 O (TCP)和Ca10 (PO4) 6(OH) 2 (HAP) .当电流密度大于 5mA/cm2 时 ,电沉积层的主要成份为羟基磷灰石 (HAP) .     

杯芳烃的配位化学──Ⅳ.对叔丁基杯[8]芳烃与钙、镉配合物的合成与表征

本文合成了对叔丁基杯[8]芳烃(H₈L)与钙、镉的固体配合物。并以元素分析、核磁共振、热谱、红外谱、紫外谱等进行表征。其配合物的组成分别为Ca(H₆L)·6dmf及Cd(H₆L)·6dmf.     

A microcalorimetric study of the association of hexacyanoferrate(II) ions with calcium and magnesium ions in aqueous solution

Using flow microcalorimetry, the ion association reaction M²⁺(aq)+Fe(CN) ₆ ^4– (aq)=MFe(CN) ₆ ^2– (aq) (M=Ca, Mg) has been studied at 25°C over the ionic strength range 0.02 to 0.08 mol-dm^–3. Analyses of the data to obtain H^o, the enthalpy change at infinite dilution, are described. The value obtained for H^o is sensitive to the kind of functions used to correct for non-ideal behavior.     

Growth kinetics and phenolics production inGlycine Max cell suspension cultures

Glycine max was used as a model plant cell suspension culture to establish relationships among growth kinetics, phenolics production, elicitor action, and peroxidase activity. Timing of elictor addition through monitoring of peroxidase provided an excellent means of optimizing yields of phenolics and reduced the time span during which phenolics were formed, negating the need for a secondary production medium. We have also determined that calcium and other cellular effectors like polyamines and organic osmolytes, when used in conjunction with elicitors, enhance phenolics production. Calcium directly enhanced elicitation, whereas polyamines and other osmolytes such as glycerol and proline extended cell viability. The study also demonstrated potential for enhancing secondary metabolite production by a combination of elicitation, cell viability stabilizers, and by addition of nutrients at the time of elicitation.     

LiCaBO3的合成和LiBO2-CaO二元体系相图

某些无水硼酸盐具有熔点高、耐潮解、损伤阈值高、光学透过波段好等优点,在材料科学领域中一直受到人们的注视。陈创天等首次得到新型紫外倍频材料—低温相偏硼酸钡。之后,又合成了具有倍频效应的晶体材料α-LiCdBO_3。     

Complete Oxidation of Methane over Palladium Supported on Alumina Modified with Calcium,Lanthanum,and Cerium Ions

The activity and thermal stability of Pd/Al_2O_3 and Pd/(Al_2O_3 MO_x)(M=Ca,La,Ce) palladium catalysts in the reaction of complete oxidation of methane are presented in this study.The catalyst supports were prepared by sol-gel method and they were dried either conventionally or with supercritical carbon dioxide.Then they were impregnated with palladium nitrate solution.The catalysts with unmodified alumina had a high surface area.The activity and thermal stability of the alumina- supported catalyst was also very high.The introduction of calcium,lanthanum,or cerium oxide into alumina support caused a decrease of the surface area in the way dependent on the support precursor drying method.These modifiers decreased the activity of palladium catalysts,and they required higher temperatures for the complete oxidation of methane than unmodified Pd/Al_2O_3.The improvement of the palladium activity by lanthanum and cerium support modifier was observed only at low temperatures of the reaction.     

以金属硫酸氢盐为催化剂在无溶剂条件下高效合成3,4-二氢嘧啶-2(1H)-酮

以金属硫酸氢盐M(HSO4)n(Ca(HSO4)2,Zn(HSO4)2和过硫酸氢钾制剂oxone○R)为催化剂催化醛、1,3-二羰基化合物和尿素进行缩合反应,在90℃及无溶剂的条件下高收率、一锅法合成了3,4-二氢嘧啶-2(1H)-酮.