超细碳氮化钛的分析和评估

采用多种技术对超细碳氮化钛进行组成分析。可分别测定吸附和化合状态的氧。晶格常数与(原子比)具有线性关系,表明碳与氮可以相互无限置换,分子式为Ti C_xN_(1-x),每一样品只有一种C/N比.固溶体是均质的。气相合成的碳氮化钛含微量杂质,包括游离碳和氯根等,主相量显著地受吸附氧量影响,可控制达97％以上。介绍了拟定的分析方法。     

交联氨基淀粉对氨基黑的吸附性能研究

合成了乙二胺改性交联氨基淀粉(CAS),并研究了其对酸性偶氮染料氨基黑的吸附性能.结果表明,CAS对氨基黑的吸附基于静电作用,溶液最优酸度为pH=3.0,5h内即达到吸附平衡.吸附动力学研究表明,其吸附过程满足准二级吸附方程式.在金属离子共存条件下,CAS对氨基黑的吸附容量增加,其中Cu2+、Ni2+离子存在下其吸附容量上升最大,增加了36.6%,金属离子的共协同效应主要由于金属离子被CAS吸附,增加了CAS的正电荷,进一步增强了与氨基黑的静电作用,使吸附容量上升.     

正电子湮没参量及其所反映物质信息的探讨

本根据正电子在凝聚态物质中的湮没机制及捕获模型,讨论了正电子湮没参量——正电子寿命谱和多普勒线形等参量所反映的物质信息,给出了各正电子湮没参量与所反映的物质信息之间的定量关系。分析了在该体系中正电子寿命参量与局域电子密度、多普勒线形参量和角关联参量与电子动量密度分布和费米面之关联。     

测量不确定度与实验方案的选择

本通过具体实例简单介绍了如何利用不确定理论进行实验方案的选择。     

钢中氧化物夹杂分析的误差来源及结果的可靠性

本文综述了采用化学-电化学方法分析钢中氧化物夹杂的误差来源。基体元素的水解、钝化、共存相的干扰和包裹相等引起正偏差;化学溶损、沉淀处理等引入的负偏差;以及随机误差。相应地提出了提高分析精度的具体措施。对这种既无标样又无标准可循的分析其结果的可靠性不仅需根据钢中氧含量而定,还需根据夹杂物的总量与分量的吻合程度来判定,此外要结合钢的化学成份,冶炼工艺,脱氧制度来综合判断。     

Rapid Method for Simultaneous Determination of Inositol Phosphates by IPC-ESI–MS/MS and Its Application in Nutrition and Genetic Research

Inositol phosphates (InsPs) have important biological functions and multiple nutritional effects. Breeding and nutrition studies of InsPs require a simple, rapid, and accurate method for high-throughput quantification. Here, we developed an ion-pair chromatography/tandem mass spectrometry (IPC/ESI–MS/MS) method for the simultaneous separation and determination of each InsP. A highly volatile ion-pair reagent (dihexylammonium acetate, DHAA) was applied to separate InsP₁–InsP₆, which were then quantified by multiple reaction monitoring (MRM) in negative ESI mode. This method could simultaneously detect InsP₁–InsP₆ within 15 min and exhibited a wide linearity (typically 0.3–1200 pmol). The lower limit of detection was 0.3 pmol for all InsPs, excluding InsP₂ (0.15 pmol) and InsP₆ (3 pmol). The method accuracy of all analytes ranged between 87 and 111% with the inter- and intra-day precision of 0.9–15 and 2.2–11%, respectively. This method was successfully applied to quantitate InsPs in different types of crop seeds, organs, and a maize inbred germplasm collection composed of hundreds of inbred lines, showing its potential for promoting the nutrition and genetic research of InsPs.     

Identification of C21 Steroidal Glycosides from Gymnema sylvestre (Retz.) and Evaluation of Their Glucose Uptake Activities

Gymnema sylvestre (Retz.) Schult is a multi-purpose traditional medicine that has long been used for the treatment of various diseases. To discover the potential bioactive composition of G. sylvestre, a chemical investigation was thus performed. In this research, four new C₂₁ steroidal glycosides sylvepregosides A-D (1–4) were isolated along with four known compounds, gymnepregoside H (5), deacetylkidjoladinin (6), gymnepregoside G (7) and gymnepregoside I (8), from the ethyl acetate fraction of G. sylvestre. The structures of the new compounds were established by extensive 1D and 2D nuclear magnetic resonance (NMR) spectra with mass spectroscopy data. Compounds 1–6 promoted glucose uptake by the range of 1.10- to 2.37-fold, respectively. Compound 1 showed the most potent glucose uptake, with 1.37-fold enhancement. Further study showed that compounds 1 and 5 could promote GLUT-4 fusion with the plasma membrane in L6 cells. The result attained in this study indicated that the separation and characterization of these compounds play an important role in the research and development of new anti-diabetic drugs and pharmaceutical industry.     

钢中氧化物夹杂差热油取峰形分离研究

实验探讨了构成峰形重叠的各种因素,对分峰参数进一步优化组合,获得良好分峰效果;试验确定了谱碳钢中若干氧化物的释放峰位,并经Ｘ－射线结构分析予以佐证,为差热抽取法测定钢中氧化物奠定了可靠的实验基础。方法特点：快速（约５ｍｉｎ）、灵敏、低成本,时获得钢中总氧物及氧化物氧量。     

Synthesis,X‐ray Diffraction Study,and Cytotoxicity of a ­Cationic p‐Cymene Ruthenium Chloro Complex Containing a Chelating Semicarbazone Ligand

An organometallic salt composed of a new cationic p‐cymene ruthenium chloro complex containing a chelating benzaldehyde semicarbazone ligand and of the known anionic p‐cymene ruthenium trichloro complex, [(η⁶‐p‐cymene)Ru(bzsc)Cl]⁺[(η⁶‐p‐cymene)RuCl₃]^– ( 1 ) (bzsc = benzaldehyde semicarbazone) was synthesized and further characterized by IR, ¹H NMR, and UV/Vis spectroscopy HR‐ESI mass spectrometry, and elemental analysis. The single‐crystal structure of 1 was also determined. The in vitro anticancer activities of the complex was evaluated against three human cancer cell lines (SGC‐7901, BEL‐7404 and CNE‐1), and the IC₅₀ values were 20.7, 71.1 and 42.6 μM, respectively.