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1.
采用粉末压片制样,用X射线荧光光谱法测定土壤、水系沉积物等样品中C、N、F、S、Cl、Br、Na、Mg、Al、Si、P、K、Ca、Ti、Mn、Fe、Co、Ni、Cu、Zn、Pb、Ga、As、Rb、Sr、Y、Zr、Nb、Th、U、Ba、La、Ce、Nd、Ge、Yb、W、Hf、Sc、Sn、Mo、Cs等42种元素。着重研究了C、N、F、S和Cl等元素的测量条件和存在问题;并研究了痕量元素的背景选择和谱线重叠校正的问题。方法的检出限,精密度和准确度绝大多数能满足覆盖区多目标地球化学调查样品的质量要求。  相似文献   

2.
南京金陵微量元素与健康研究所用元素医学食疗法治疗冠心病、癌症、脑血管病、老年痴呆症、糖尿病、艾滋病、帕金森氏综合症、脑中风及其后遗症、小儿脑瘫、系统性红斑狼疮、癫痫、精神分裂症、血小板减少、肌痉挛、肌无力、肌萎缩、胆汁反流、偏头痛、前列腺肥大、性机能低下、不孕、不育、肝胆结石、脱发、斑秃、白瘢风、银屑病、再障贫血、血友病、白血病、荨麻疹、哮喘、风湿、类风湿、高(低)血压、高血脂、高血糖、高血沉、高尿酸、动脉硬化、骨质疏松、元素中毒症,地方病,遗传病等现代医学界束手无策的疑难病症,先后都获得了很好的疗效。  相似文献   

3.
1932年8月1日,当时的教育部在南京召开化学讨论会,讨论化学译名、国防化学及课程标准。来自各地曾经留学欧、美、日的化学学者,丁嗣贤、王箴、王琎、巴文峻、戈福祥、朱骥、沈熊庆、吴承洛、吴沆、李方训、李乃尧、李运华、周萃禨、林大中、林继庸、邵家麟、胡安恺、姚万年、陶延桥、容启兆、徐宗涑、徐作和、时昭涵、倪则埙、高露德、张江树、张洪沅、张郁岚、张资琪、康辛元、陈之霖、陈可忠、陈裕光、曾昭抡、程瀛章、邬保良、叶  相似文献   

4.
南京金陵微量元素与健康研究所用元素医学食疗法治疗冠心病、癌症、脑血管病、老年痴呆症、糖尿病、艾滋病、帕金森氏综合症、脑中风及其后遗症、小儿脑瘫、系统性红斑狼疮、癫痫、精神分裂症、血小板减少、肌痉挛、肌无力、肌萎缩、胆汁反流、偏头痛、前列腺肥大、性机能低下、不孕、不育、肝胆结石、脱发、斑秃、白癜风、银屑病、再障贫血、血友病、白血病、荨麻疹、哮喘、风湿、类风湿、高(低)血压、高血脂、高血糖、高血沉、高尿酸、动脉硬化、骨质疏松、元素中毒症,地方病,遗传病等现代医学界束手无策的疑难病症,先后都获得了很好的疗效。  相似文献   

5.
含钙高的食物:牛奶、黄豆、乳制品、海参、海带、蚕豆、豆制品、芝麻酱、虾皮、燕麦、小麦、酸奶、牛肉等。含镁高的食物:荷叶、香蕉、黄豆、蕃茄、绿豆、红小豆、蕃石榴、蜂蜜、燕麦等。含锌高的食物:牡蛎、猪肝、鱼类、高锌鸡蛋、板栗、核桃、红枣、黄鳝、海参等。含铁高的食  相似文献   

6.
《大学化学》2004,19(5):64-64
“涌泉杯”第 4届全国大学生化学实验邀请赛 2 0 0 4年 7月 13日至 7月 15日在厦门大学举行 ,北京大学、北京化工大学、北京科技大学、复旦大学、福州大学、广西大学、黑龙江大学、湖北大学、华东理工大学、华南师范大学、吉林大学、兰州大学、辽宁大学、南京大学、南开大学、清华大学、山东大学、山西大学、陕西师范大学、上海交通大学、石油大学、四川大学、武汉大学、西北大学、厦门大学、扬州大学、浙江大学工科基地、浙江大学理科基地、郑州大学、中国农业大学、中南大学、中山大学等 31所院校派出 32个代表队参赛 ,参赛学校和人数是历…  相似文献   

7.
《分析试验室》2006,25(12):7-7
由中国分析测试协会和中国石油学会石油炼制分会共同主办的全国第一届近红外光谱学术会议于2006年10月28日至30日在北京西郊宾馆的会议中心举行。来自清华大学、浙江大学、天津大学、南开大学、吉林大学、上海交通大学、西安交通大学、哈尔滨工业大学、中国农业大学、中南大学、第二军医大学、后勤工程学院、第二炮兵工程学院、海军航空工程学院、暨南大学、广西大学、首都师范大学、山东轻工业学院、中国计量学院、中科院光机所、中科院上海技术物理研究所、石油化工科学研究院、中国林科院、中国农业科学院、总后油料研究所、中国药品生物制品检定所、南京地矿所、  相似文献   

8.
前不久,由军事医学科学院卫生学环境医学研究所高志贤博士主持的“食品安全快速检测方法及装备研究”项目通过了天津市科委的鉴定。这项成果包括甲醇、亚硝酸盐、巴比妥、桐油、安妥、铅、汞、敌鼠、杂醇油、锰、有机磷农药、钾、组胺、氰化物、磷化物、生物碱、镉、酸度、硝酸盐、酸价、过氧化值、游离矿酸、甲醛、细菌总数及大肠杆菌等26项检测指标的前处理和快速检测方法,其中甲醇、亚硝酸盐、桐油、铅、  相似文献   

9.
缺钙(Ca)症状:佝偻病、骨质疏松、腰腿酸软无力、手足麻木、抽搐、易激动,头痛、经期痛、记忆力下降、生殖能力下降、白发、失眠、盗汗、精神失常、尿石症。缺镁(Mg)症状:心肌坏死、心肌梗塞、代谢性碱中毒、动脉硬化、心血管病、关节炎、白血病、白内障、糖尿病、胃肿瘤、胃结  相似文献   

10.
《化学学报》2005,63(11):F002-F002
长春工程学院是一所以工科为主,兼有理、文、管等多学科的全日制普通本科学校。学院立足地方、面向全国水利、电子、电力、建筑、机械、化工、冶金、交通、市政、工商、经贸、资源开发等行业,培养、技术、管理、经济、人文、艺术等方面的高级应用型人才。  相似文献   

11.
Novel monoazacryptand-type fluorescent chemosensors, (derived from an 18-crown-6) and (derived from a 15-crown-5) both with a pyrene ring as their photoresponsive moiety, were synthesized. Their fluorescence properties for alkali metal and alkaline earth metal cations in water were then examined. The detection of metal cations was accomplished by a change in the fluorescence intensity of the host compounds, based on a photoinduced electron transfer (PET) mechanism. In aqueous solution, showed little fluorescence upon the addition of Ba2+ because of the very weak complexation with Ba2+, but the presence of micelles of polyoxyethylene(10) isooctylphenyl ether (Triton X-100) enabled to show highly sensitive and selective Ba2+ detection among alkali metal and alkaline earth metal cations. With respect to the selective fluorescent detection of important metal cations (Na+, K+, Mg2+, Ca2+) relevant to living organisms, was found to detect K+ with high selectivity in aqueous micellar solutions of polyoxyethylene(20) sorbitan monostearate (Tween-60). The selectivity for metal cations was mainly dependent on the goodness of fit of the host cavity and the metal cation size. In the presence of anionic surfactants, detected alkaline earth metal cations more effectively than alkali metal cations.  相似文献   

12.
Lipophilic cyclodextrin (CD) derivatives were prepared to extract alkali metal cations from a water phase into an organic phase. The extraction equilibrium constant, K ex, was determined by the solvent extraction method using UV absorption spectroscopy. Hydroxyl groups at the carbons in the 2,6-positions of CD molecules were dipropylated to add the hydrophobicity for dissolving into organic solvents, and furthermore hydroxyl groups at the carbons in the 3-position of these derivatives were acylated as complexing sites with the alkali metal cations. These CD derivatives formed a 1 : 1 complex with alkali metal cations, except for the case of Li+, and transported the alkali metal cations from a water phase into a benzene phase. The initial concentrations of alkali metal cation and picrate anion in the water phase and that of the CD derivatives in the organic phase strongly influenced the extraction equilibrium. Extraction of the alkali metal cation by the derivative without acyl groups was not detected. K ex values of these CD derivatives are of the same order of magnitude as or larger than those of crown ethers. The order of the K ex values in all cases is Li+ < Na+ < K+ Rb+ Cs+, although these CD derivatives have no special selectivity for the alkali metal cations. The cation extraction mechanism was interpreted by an induced-fit mechanism.  相似文献   

13.
Thirty-four nano-basket derivatives of di-ionizable calix[4]arene conformers in nine scaffolds bearing two pendant groups of N-(R)-sulfonyl carboxamides were synthesized and examined using isothermal titration calorimetry. The binding mechanisms of synthesized conformers toward alkali metal cations were evaluated and two main interactions were assessed including cation?C?? interaction between alkali metal and the aromatic unit of conformer as well as the strong binding ion?Cdipole interaction between nitrogen atoms in the pendant groups and alkali cation. The ITC data revealed that the bindings of cone and partial-cone conformers toward alkali metal cations exhibited one-step mechanism, while both 1,2 alternate conformer bounds the alkali metal cations in a two-step mechanism.  相似文献   

14.
The binding constants of various alkali metal cations with water-soluble p-sulfonatocalix[8]arene (Calix-S8) were determined spectrophotometrically by using the inclusion equilibrium of thionine (Th) dye as a chemical indicator. Depending on the kind of alkali metal cations, the inclusion constants of Calix-S8 for Th decrease steeply with an increase in salt concentrations. Alkali metal cations compete with the organic guest Th in the Calix-S8 inclusion. Based on a competitive binding experiment, the binding constants of alkali metal cations with Calix-S8 were evaluated to be 17, 60, and 11 dm6 mol?2 for Na+, K+, and Cs+, respectively. We have demonstrated an absorption-based method of evaluating the binding constants of spectroscopically inert metal cations with Calix-S8 and shown the effects of salts on the molecular recognition of Calix-S8.  相似文献   

15.
Bis-crown ethers in which the benzo-15-crown-5 units were linked to 1,1′-positions of metallocene (M = Fe or Ru) with amide, ester, or ? C? C? bonds were synthesized. Complexing ability of the compounds with alkali, alkali earth, and transition metal cations were measured by the solvent extraction method. The results showed that these crown ethers had high affinity toward alkali metal cations (Li+, Na+, K+, and Rb+) and heavy-metal cations (Ag+ and Tl+). The difference of complexing ability for metal cations between ferrocene and ruthenocene derivatives could not be detected significantly. The extractability of metallocene-bis-crown ethers for metal cations was more larger than that of the corresponding mono-crown ethers, and irregular increments of extractability were explained by assuming the existence of a mixture of 1:1 and 2:1 complexes.  相似文献   

16.
The collision-induced dissociation of lasalocid and monensin A bound to alkali metal cations has been investigated using electrospray MS/MS. The binding affinity for the metal cations, as measured with collision-induced dissociation, was found to depend on their ionic radius, decreasing with increasing radius. Monensin A was observed to have a greater binding affinity for alkali metal cations than lasalocid acid.  相似文献   

17.
A series of ethyl acetate (nBP-Es) and trioxyethylene ether (nBP-OE) derivatives of linear all-ortho methylene-linked oligomers of p-tert-butylphenol (n = 1–7) were prepared, and cation extraction properties were determined. For alkali metal cations, nBP-Es showed the affinity, and especially 5BP-Es showed the selectivity for Na+. On the other hand, nBP-OE also showed sufficient affinity; however, the extraction behavior was completely different from that of nBP-Es, that is, the affinity of even membered BP-OE was higher than that of the odd membered. nBP-Es extracted cations by forming a cavity winding around them, while nBP-OE extracted with two trioxyethylene chain picking up cations. For alkaline earth metal cations, nBP-Es extracted more than that for alkali cations. Particularly, 7BP-Es showed the highest affinity for larger cations, Sr2+ and Ba2+, among phenolic oligomers and 18-crown-6 compound. On the other hand, nBP-OE showed a lower affinity than that for alkali cations. It was concluded that the linear phenolic oligomers extracted alkali and alkaline earth metal cations and the kind of ion ligand introduced influenced the affinity and the selectivity. © 1996 John Wiley & Sons, Inc.  相似文献   

18.
运用abinitioHartree-Fock从头算,微扰MP2和密度泛函B3LYP方法在不同的基组水平上对碱金属阳离子-苯复合物体系的可能构型进行了自由优化,得到了复合物的能量最低构型为碱金属阳离子位于苯环平面的正上方,频率计算结果表明该结构为稳定结构.复合物的键长、原子净电荷、分子轨道、前沿轨道能量、Mullicken键级等都表明,碱金属阳离子和苯环碳原子之间的作用包含p-π作用方式,碱金属阳离子与苯结合时电子从苯环向碱金属阳离子转移,形成电荷转移复合物.它们之间的结合方式和氢键的结合方式相似,但计算得到的热力学参数表明复合物中碱金属阳离子与苯之间的结合强度远远大于典型的氢键,尤其是锂离子-苯复合物的生成焓已和普通的化学键相当.复合物的红外特征振动频率位于200^-^1附近,对应于碱金属阳离子垂直于苯环平面的来回振动,同时形成复合物后,原来位于3200cm^-^1的苯的C--H振动红外活性消失。  相似文献   

19.
An unmodified silica gel (Develosil 30-5) column (150×4.6 mm I.D.) has been applied to the ion chromatographic separation of alkali, alkaline earth and transition metal cations. The retention behavior of the above cations on the bare substrate was investigated using a number of weak inorganic and organic acid eluents. During this investigation, several separations were achieved and the most suitable eluent conditions were identified. It was concluded that: (a) 1.5 mM HNO3-0.5mM pyridine-2,6-dicar☐ylic acid eluent was the most effective for the simultaneous separation of common alkali and alkaline earth metal cations, (b) 1.5 mM oxalic acid eluent resulted in the best separation of alkali, alkaline earth, and transition metal cations, (c) 0.5 mM CuSO4 eluent could be used for the separation of alkali metal cations alone and (d) 0.5 mM ethylenediamine-oxalic acid eluent at pH 5.5 resulted in themost efficient separation of both alkaline earth and transition metal cations.  相似文献   

20.
采用自由配体法,将铁邻菲啰啉(Fe(phen)3)配合物封装在含有不同碱金属阳离子的Y型分子筛中,制备了系列Fe(phen)3/M-Y(M=Li+,Na+,K+和Cs+)催化剂.采用X射线衍射、红外光谱、紫外-可见光谱、热重-差热分析、电感耦合等离子原子发射光谱、N2吸附-脱附以及催化氧化反应考察了碱金属离子对Fe(phen)3/M-Y催化剂物化性质和催化氧化性能的影响.结果表明,交换有不同碱金属离子的Y型沸石中Fe(phen)3的封装量不同,而且Fe(phen)3在Y型沸石中的热稳定性随着碱金属离子半径的增加有所降低,其中Fe(phen)3/Li+-Y具有最高的配合物封装量和热稳定性能.在环己烷或苯乙烯氧化反应中,在较低的反应温度下,Fe(phen)3/K+-Y表现出最高的催化活性,而在较高的反应温度下,Fe(phen)3/Cs+-Y的催化活性最高,碱金属离子对Fe(phen)3/M-Y催化氧化性能的影响是电子效应、空间限制作用和扩散效应的综合结果.  相似文献   

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