利用巯基棉富集分离和鲁米诺-过氧化氢-铬(Ⅲ)化学发光体系测定水样中痕量砷

本文提出了用鲁米诺－过氧化氢－铬（Ⅲ）化学发光体系结合巯基棉时As（Ⅲ）的分离．建立了快速简单的测定水样中痕量砷的新方法。检测范围宽（0．10～1．0×104μg／L）、检测下限为3．4×102μg／L，且选择性好。直接用于环境水样的分析，5次测定的相对标准偏差为4．2％～10．6％；回收率为95％～103％。     

二安替比林-(2-甲氧基)-苯基甲烷光度法测定铬

合成了新试剂二安替比林－（2－甲氧基）－苯基甲烷（DAoMM）；研究了在Mn（Ⅱ）存在下，DAoMM与Cr（Ⅵ）生成橙黄色化合物。该化合物最大吸收位于480nm；表观摩尔吸收系数为ε=1．58×105L·mol－1·cm－1和ε2=9．85×104L·mol－1·cm－1化合物至少稳定20h。服从比尔定律范围0～1．6×102μg／LCr（Ⅵ）和2×102～8×102μg／LCr（Ⅵ）。用于含铬废水和电镀废液中铬的测定，结果满意。     

电感耦合等离子体发射光谱法(ICP-AES)测定黑豆和红小豆中15种元素

采用ICP—AES法同时测定黑豆和红小豆中Na,Sn,Ca,Zn,Cu,Mg,Al,Fe,P,K,Si,Se,Ba,Mn,M015种元素含量,并对各元素进行了加标回收实验,黑豆和红小豆中各元素的平均回收率在93．11％～102．15％,相对标准偏（RSD）在0．83％0～2．8％,检出限介于0．11～14．09Fg／L。建立了简便、快速、准确和稳定的测定黑豆和红小豆中元素的测定方法。结果显示在黑豆和红小豆中K,Ca,P,Mg,Mn,Fe,Zn等常量元素和微量元素含量较高。红小豆中Ca,Mg,Fe,Zn等营养元素的含量较黑豆中的高。     

儿童易疲劳与血清中微量元素含量的相关性研究

测定了1562名儿童(其中包括153名易疲劳儿童)血清中Zn、Fe、Cu、Ca、Mn和Pb的含量。研究发现,易疲劳儿血清Ca含量(84.4±12.5μg/mL)显著低于对照组儿童(88.5 4±13.4μg/mL),P<0.05;Fe含量(1.094±0.22μg/mL)显著高于对照组儿童(1.07 4±0.22μg/mL),P<0.05;Mn含量(0.040 4±0.035μg/mL)非常显著高于对照组儿童(0.035 4±0.013μg/mL),P<0.001。     

我国66种蔬菜矿质营养成分的综合评价

通过对我国66种常用新鲜蔬菜的K、Na、Ca、Mg、Fe、Mn、Zn、Cu、P、Se等10种矿质营养元素含量数据的深度挖掘,用聚类分析法建立了蔬菜的矿质营养成分谱。结果表明,66种蔬菜按其所含矿质元素含量的高低及其组合状况可有序地划分为6个组：即富K、P、Zn型蔬菜,富Ca蔬菜,富Mn、Fe、Se型蔬菜,富zn、Fe、P型蔬菜、各种营养成分的配合较为均衡的蔬菜和低K、P型蔬菜。按照蔬菜的w（Zn）／w（Cu）、w（Ca）／w（Mg）、w（Na）／w（K）比值序列,为人们尤其是高血压和冠心病患者科学合理地选择和搭配蔬菜提供了参考。     

微波消解ICP-AES法同时测定蒙药新-Ⅱ中多种微量元素及Ca/Mg,Cu/Zn比值的分析

采用微波消解ICP—AES法同时测定蒙药新-Ⅱ中Ca、Mg、Fe、Zn、Ni、Mn、Cu、Pb等15种微量元素,并对蒙药新-Ⅱ中Ca／Mg,Cu／Zn比值进行了初步的分析。结果表明,蒙药新-Ⅱ中含有多种微量元素,其中人体有益的微量元素Ca、Mg、Fe、Cu、Ni、Zn、Mn的量相对高,即Ca〉Mg〉Fe〉Mn〉Zn〉Ni〉Cu,而人体有害微量元素Cd、Pb、Ag的量相对较低,Ca／Mg和Cu／Zn比值分别为4．1760、0．6077。加标回收率在97．5％～105．5％之间,相对标准偏差RSD≤2．7％,检出限≤0．008μg／mL。     

高血压患者血清中八种金属元素的

通过对48名高血压患者和52名正常健康人进行血清中八种金属元素的检测,探讨了人体必需金属元素的含量变化是否与患高血压疾病有直接的关系。采用离心分离的方法处理样品,用火焰原子吸收分光光度法检测样品中钙、镁、钾、钠、锌、铜、铁和锰的水平含量。结果表明,患高血压组血清Na、Mg、Zn、Fe、Mn的水平含量均高于健康对照组,其中Na、Mn两组间比较差异显著（P＜0．05）,Zn、Fe两组间比较差异非常显著（P＜0．01）,Mg两组间比较差异无显著性（P＞0.05);患高血压组血清Na／K比值均高于健康对照组,Ca/Mg、Cu/Zn比值均低于健康对照组。检测的八种金属元素在人体内的含量多少与患高血压疾病有一定的关系。提示适当增补体内的Ca、K、Cu和Mg含量,减少Na的过多摄入,科学控制Zn、Fe、Mn的增加,注意体内Na/K、Ca/Mg和Cu/Zn比值的平衡关系,降低Na/K比,提高Cu/Zn比,补Ca的同时一定要注意适当补充Mg,保持体内各元素间的相互依赖关系,有利于高血压病的预防和治疗。     

运动加强氟化钠对去卵巢大鼠骨元素代谢的影响效应

用测定骨元素含量的方法,观察了运动对氟化钠（NaF）抗去卵巢大鼠骨元素代谢的影响效应。将健康4月龄雌性SD大鼠30只,用抽签法随机分成5组：正常对照组,假去卵巢组,去卵巢组,去卵巢＋NaF组和去卵巢＋NaF＋运动组;去卵巢＋NaF组和去卵巢＋NaF＋运动组大鼠于去卵巢手术后第2天开始给予NaF溶液灌胃,1mg／（kg·BW）,1次／d,持续11周;去卵巢＋NaF＋运动组大鼠于去卵巢术后第7天开始运动训练,每周5d,每天连续匀速跑45min,16m／min,跑道倾角0。,持续10周。结果表明,去卵巢大鼠骨Ca、S、Mg、Zn、Co、Mn等元素含量显著降低,骨P含量增加;NaF可使去卵巢大鼠降低的骨Ca、S、Mg、Co、Mn等元素含量回升,骨P含量回降;运动与NaF联合应用能使骨Ca、S、Mg、Zn、Co、Mn等元素含量显著回升,骨P含量显著回降。提示运动可加强NaF对抗由于去卵巢引起的大鼠骨元素代谢紊乱的作用。     

儿童神经过敏与血清中6种无机元素含量相关性研究

测定了1261名儿童(其中包括73名神经过敏儿童)血清中Zn、Fe、Cu、Ca、Mn和Pb的含量。研究发现,神经过敏患儿血清Zn含量(0.95±0.20μg/mL)显著低于对照组儿童(0.97±0.23μg/mL),P<0.05;Mn含量(0.03±0.01μg/mL)非常显著低于对照组儿童(0.04±0.02μg/mL),P<0.01。     

食管癌患者肿瘤组织中硒含量的调查测定

应用2，3-二氨基萘荧光测定法对36例食管癌患者癌组织与癌旁组织及血清中硒的含量进行了测定。结果表明，癌组织中硒含量平均为1．325±0．81μg／g干重，癌旁组织为0．893±0．68μg／g干重，两者差异显著（P＜0．05）；血清中硒含量为0.6033±0．0520μmol／L，对照组20例献血员血清为0．8034±0．0650μmol／L，亦有显著性差异（P＜0．05）。提示硒在抗肿瘤的过程中有一定作用。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.