Effects of BaCl_2 on slow vacuolar ion channels on radish by patch-clamp

Effects of BaCl2 on slow vacuolar ion channels on radish by patch-clamp YANG Pin (杨 频) & ZHANG Liping (张丽平) Institute of Molecular Science, Shanxi University, Taiyuan 030006, China Correspondence should be addressed to Yang Pin (email: yangpin@sxu.edu.cn)     

校正矩阵同时分光光度法测定人发中钙、镁、锌

将校正矩阵计算法应用于分光光度法中,同时测定了人发中的钙镁锌含量。讨论了方法原理和最佳实验条件,对４个发样和模拟样进行了测定,取得满意结果。     

ICP-AES法测定红土镍矿中镍、钙、钛、锰、铜、钴、铬、锌与磷的含量

建立了ICP-AES法测定红土镍矿中Ni;Ca;Ti;Mn;Cu;Co;Cr;Zn和P含量的方法。样品用HCl、HNO3溶解,加入HF和HClO4,加热至HClO4烟冒尽,用HCl溶解盐类,过滤,采用ICP-AES法同时测定滤液中Ni、Ca、Mn、Cu、Co、Zn、P;残渣经灼烧、挥硅、K2S2O7熔融、HCl浸取,所得溶液与滤液合并,测定溶液中Cr和Ti含量。方法检出限:P为0.022μg/mL,其它元素在0.0032～0.0085μg/mL之间,方法的精密度(n=7)在1.4%～2.9%之间。分析结果与分光光度法、XRF法和AAS法分析结果的相对误差:Ni、Cu、Co、Cr小于5%,Ti和Mn小于10%,Zn小于15%,Ca和P小于19%。     

La0.8Ca0.2MnO3纳米线的制备及表征

利用Sol-gel法结合氧化铝模板技术制备了La0.8Ca0.2MnO3纳米线, 并研究了两种热处理方法对 La0.8Ca0.2MnO3纳米线结构和形貌的影响. 快速升温到800 ℃得到的La0.8Ca0.2MnO3纳米线较粗, 其直径大于氧化铝模板的孔径, 而经过缓慢升温到400 ℃预处理再升温到800 ℃得到的La0.8Ca0.2MnO3纳米线, 其直径和氧化铝模板的孔径相当, 都约为35 nm. X射线衍射和透射电镜分析结果表明, 两种方法得到的 La0.8Ca0.2MnO3纳米线都是具有钙钛矿结构的属于单斜晶系的多晶材料.     

Synthesis of marine guanidine alkaloids and their application as chemical/biological tools

Ptilomycalin A and crambescidins, novel marine guanidine alkaloids, have a unique pentacyclic guanidine structure, and exhibit a considerable array of biological activities. The first method developed for the synthesis of the pentacyclic guanidine core structure involved successive 1,3-dipolar cycloaddition reactions and resulted in the first total synthesis of crambescidin 359. The synthesis of other pentacyclic guanidine derivatives has been based on this methodology and applied as tools for studying biological activities, and as chemical reaction catalysts.     

稀土冠醚配合物的研究XXI. 单羟基冠醚与钙、稀土元素间的竞争配位及其钙配位化合物的晶体结构

研究了单羟基冠醚配位体6-羟基-2, 3, 9, 10-二苯并-1, 4, 8,11, 14-五氧杂环十六-2, 9-二烯(L)对钙和镧系元素的竞争配位反应, 发现该配位体在我们的实验条件下对钙的配位能力要明显大于对重稀土的配位能力; 同时研究了标题大环配位体和钙的配位化合物的晶体结构, 该配位化合物的分子结构式为[Ca(NO3)(H2O)L](NO3),Mr=528.47, 晶体属单斜晶系, α=1.5285(6), b=0.9713(3),c=1.5134(7)nm, β=98.79(3)ⅲ, V=2.2205nm^3, Dex=1.521g/cm^3,Dc=1.527g/cm^3, Z=4, 空间群为P21/c。     

Dawn of Calcium Batteries

Calcium batteries are a potentially sustainable, high‐energy‐density battery technology beyond Li ion batteries. Now the development of Ca batteries has become possible with a newly invented Ca electrolyte capable of reversible Ca deposition/stripping at room temperature.     

火焰原子吸收光谱法测定高血压患者头发中锌铜钙镁

用火焰原子吸收光谱法测定高血压患者45例及健康对照者34例头发中锌、铜、钙、镁的含量。结果表明,高血压患者头发中锌、铜、钙含量显著低于健康对照组（p〈0．05）,镁含量极显著低于健康对照组,揭示体内锌、铜、钙、镁元素含量与高血压发病存在一定关系。     

Tb3+离子发光探针研究Ca2+,La3+和Al3+与拟南芥钙调素的竞争结合

利用Tb3 离子的发光, 研究了Tb3 与拟南芥钙调素 (CaM)结合的荧光光谱及荧光滴定曲线特点, 然后利用Tb3 4*CaM系统在221 nm直接激发和280 nm敏化激发的光谱变化研究了Ca2 , La3 和Al3 与拟南芥钙调素 (CaM) 的竞争结合作用. 结果表明: Tb3 , La3 与钙调素的竞争结合能力强于Ca2 , 而Tb3 的竞争结合力又大于La3 , Ca2 与钙调素的结合力远大于Al3 . 竞争实验的结果从分子水平上揭示了Tb3 , La3 和Al3 等金属离子生物效应可能的分子机制.     

Modified Ceria-Zirconia Fluorite-Like Catalysts for the Combustion of Methane

For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on their structural features, surface/bulk oxygen reactivity and catalytic activity in methane combustion are considered. With up to 20 mol% doping, a structural type of homogeneous solid solutions of anion-deficient fluorite with disordered anion vacancies is formed. Doping by transition metal cations or Pt increases the mobility and reactivity of the surface/bulk oxygen. A broad variation in specific rates of methane combustion for the studied systems was observed, suggesting structural sensitivity of this reaction. In general, there is no universal relationship between the oxygen mobility, the reactivity and the catalytic activity in methane combustion, which is explained by the factor of specific methane activation on surface active sites. For the Pt-promoted samples, Pt efficiency in methane activation depends on the Pt-support interaction, and the most favorable ones being mixed Pt/MnOx and Pt/NbOx clusters on the surface of the supports that exhibit high lattice oxygen mobilities.