浙江省宁波、海宁部分地区幼儿头发和全血中的微量元素相关性研究

测定了浙江省宁波、海宁部分地区223例3-4岁健康幼儿同一个体头发和全血铅和锌含量,并研究两类样本两种微量元素的相关性。发现除血锌男女性别间含量差异不明显外,发中的锌、铅,全血中的铅均有显著的性别差异;无论是头发或是全血,男性或女性铅和锌均呈负相关且大多数有显著性;发铅和血铅男性和女性均呈显著正相关,而发锌与血锌女性也呈显著相关。本文还求出发铅与血铅、发锌与血锌含量间的一元线性回归方程。     

幼儿头发锌、铅含量与身高、体重关系的研究

测定了深圳市南山区486名3岁儿童的身高，体重及其发锌，铅的含量。并对儿童头发锌，铅含量与身高。体重之间的关系进行了分析。结果显示，儿童的身高，体重与发锌含量呈显著的正相关。而与发铅呈显著负相关。证实锌具有促进儿童体格发育的作用。而铅则对体格发育具有妨碍作用。     

幼儿头发中微量元素含量相关性研究

为探讨儿童头发中微量元素是否有协同或拮抗作用,测定了646名1－3岁和3803名4－7岁儿童头发中的Zn,Fe,Cu,Ca,Mn和Pb含量,并研究了各元素间的相互关系,结果表明：1－3岁幼儿头发中Zn,Fe,Cu,Ca,Mn和Pb各元素间均呈正相关,4－7岁儿童的发锌含量与发铅含量呈非常显著负相关（P值均＜0．001）,其它各元素间均呈正相关。     

学龄儿童智商与微量元素含量关系研究

为了解头发微量元素含量与学龄儿童智商之间的关系,本文测定了深圳市某小学570名7－13岁低智商儿童和正常儿童的IQ值及其头发中七种元素（I、Zn、Fe、Cu、Ca、Mn、Pb）的含量,并对低智商儿童及正常儿童头发中的元素含量作了比较。结果表明,低智商儿童头发碘、锌、钙的含量显著低于正常儿童头发中的含量,而发铅则显著高于正常儿童的含量。说明儿童智商高低与机体碘、锌、钙以及铅的含量有密切关系。     

铅如何影响儿童的智力、行为和心理

铅对人体损害是广泛的多系统的 ,其中神经系统是最易受其损害的重要器官 ,儿童更易受害 ,且铅对儿童是以中枢神经系统损害为主。中枢神经毒性最普遍的表现形式是智力和行为 (包括感觉功能、运动能力、注意力、视觉、记忆、情感状态等 )的异常。我国天津学者岳仲彦等测定了 3 60例智力低下儿童头发中的微量元素含量 ,发现智力低下者头发锶、钙含量比正常人 (对照组 )显著降低 ,而随着智力低下程度的加重 ,头发中锌含量明显降低 ,头发中铅含量显著增加。铅如何影响儿童的智力、行为和心理     

幼儿头发中微量元素含量与身高、体重关系研究

普查了４４９名１－６岁儿童头发中锌、铁、铜、钙、锰、铅含量,用分层聚类分析法对其身高、体重与各元素进行相关分析。幼儿身高与头发中锌含量呈相关关系,与头发中铅含量呈负相关关系。体重与头发中锌含量呈显著的正相关关系。与头发中铅含量呈负相关关系。说明锌有利于身体发育,而铅对身体发育不利。     

深圳西丽地区幼儿头发及血清中铅含量与幼儿不良习惯的关系研究

测定了深圳市西丽地区531名1－8岁正常幼儿头发及290名幼儿血清中的Pb含量，并分别与287例多动症和251例异食癖患儿头发和血清中的Pb含量比较。结果表明，异食癖及多动症儿童头发和血清中铅含量均显著高于正常儿童。头发中的Pb较高，血清中的Pb也较高。异食癖患儿发铅和血铅含量有极其显著的相关性。     

矮小身材儿童头发微量元素分析

采用电位溶出法检测了４２例矮小身材儿童的头发锌,铜,铅,镉含量,结果显示大多数患儿发锌含量低于正常儿童,１／３患儿发铜含量减少,仅４例发铜值增高;发铅含量高于正常者３例,占７．１４％,所有患儿发镉含量均在正常范围内。     

幼儿身高、体重和头发、血液锌铅含量关系的研究

同步检测了151例3-4岁健康幼儿的身高、体重以及头和全血中的锌、铅含量。研究了身高、体重和锌、铅含量的关系,指出无论是发锌或血锌含量与身高、体重多数呈正相关,但发铅与身高、体重主要呈负相关,血铅与身高、体重的关系较为复杂,多为非线性的二次函数关系。     

广州员村地区0—6岁健康儿童头发微量元素分析

为观察不同年龄、性别健康儿童微量元素之间的关系，对广州员村地区７５４名０￣６岁儿童进行了头发微量元素锌、铁、铜以及宏量元素钙测定。结果表明：新生儿发锌明显高于其他年龄组；６个月￣１岁儿童发锌、铁、钙均低于其他年龄组，与各年龄组比较有显著差异；５￣６头儿童发铜低于其他年龄组，且女童发铜、钙高于男童（Ｐ〈０．０５），提示在不同年龄、性别儿童之间头发微量元素含量存在一定差异。     

Phosphorimetric determination of procaine,phenobarbital, cocaine,and chlorpromazine in blood serum,and cocaine and atropine in urine

A new sensitive and rapid method is proposed for the determination of procaine, cocaine, phenobarbital and chlorpromazine in blood serum, and cocaine and atropine in urine. The drug is extracted from the biological fluid using chloroform or ether, the solvent is evaporated and the resulting residue is dissolved in EPA; the EPA solution is measured phosphorimetrically. Recoveries of 100 ± 6% and relative standard deviations of 2–5% are obtained for most drugs.     

Photodegradation assessment of amisulpride,doxepin, haloperidol,risperidone, venlafaxine,and zopiclone in bulk drug and in the presence of excipients

Monatshefte für Chemie - Chemical Monthly - Photostability of amisulpride, doxepin, haloperidol, risperidone, venlafaxine, and zopiclone in APIs and powdered tablets during exposure to UVA...     

Determination of Cd, Co, Cr, Cu, Fe, Ni and Pb in Milk, Cheese and Chocolate

 Combined analytical procedures consisting of wet digestion step followed by instrumental determination – differential pulse cathodic stripping voltammetry (DPCSV) or electrothermal atomic absorption spectrometry (ETAAS) – as well as a direct analysis method – slurry sampling ETAAS – for the determination of Cd, Co, Cr, Cu, Fe, Ni and Pb in milk, cheese and chocolate are described and compared. Wet digestion using a mixture of HNO₃-HClO₄-H₂O₂ is proposed for complete matrix decomposition prior to trace analyte determinati on by DPCSV or ETAAS. A mixture of HNO₃-H₂O₂ is used for slurry preparation. Optimal instrumental parameters for trace analyte measurements are presented. The reliability of the procedures has been verified by analyzing standard reference materials. Results obtained are in good agreement with the certified values and the relative standard deviations (for these results) are in the range 5–10% for wet digestion DPCSV or ETAAS and 3–9% for slurry sampling ETAAS in the range of 2 μgċg⁻¹ (Cd) to 12 μgċg⁻¹ (Fe). Received August 24, 1999. Revision January 20, 2000.     

Catalysis in the Synthesis of S,N-Heterocycles and O,N-, S,N-, and O,S,N-Macroheterocycles

The review systemizes and generalizes published data on the catalytic syntheses of six-, seven-, and eight-membered S,N-heterocycles and O,N-, S,N-, and O,S,N-macroheterocycles.     

Free energy, energy, and entropy of swelling in Cs-, Na-, and Sr-montmorillonite clays

A Monte Carlo method for grand canonical and grand isoshear ensemble simulations has been used to characterize the free energy, energy, and entropy of clay mineral swelling. The Monte Carlo approach was found to be more efficient at simulating water content fluctuations in the highly constrained clay environment than a previously developed molecular dynamics method. Swelling thermodynamics calculated for Cs-, Na-, and Sr-montmorillonite clays indicate a strong dependence of swelling on the interlayer ion identity, in agreement with various experimental measurements. The Sr clay swells most readily, and both the Na and Sr clays prefer expanded states (two-layer hydrate or greater) when in contact with bulk water. In contrast, swelling is inhibited in the Cs clay. Differences in swelling behavior are traced directly to the tendency of the different ions to hydrate. The swelling free energies are decomposed into their energetic and entropic components, revealing an overall energetic driving force for the swelling phenomena. Entropic effects provide a smaller, mediating role in the swelling processes. The results provide a unique molecular perspective on experimentally well-characterized swelling phenomena.     

Use,analysis, and regulation of pesticides in natural extracts,essential oils,concretes, and absolutes

Natural extracts used by the fragrance and cosmetics industries, namely essential oils, concretes, resinoids, and absolutes, are produced from natural raw materials. These are often cultivated by use of monoculture techniques that involve the use of different classes of xenobiotica, including pesticides. Because of these pesticides’ potential effect on public health and the environment, laws regarding permitted residual levels of pesticides used in cultivation of raw materials for fragrance and cosmetic products are expected to become stricter. The purpose of this review is to present and classify pesticides commonly used in the cultivation of these natural raw materials. We will summarize the most recent regulations, and discuss publications on detection of pesticides via chemical analysis of raw natural extracts. Advances in analytical chemistry for identification and quantification of pesticides will be presented, including both sample preparation and modern separation and detection techniques, and examples of the identification and quantification of individual pesticides present in natural extracts, for example essential oils, will be provided.

Simultaneous activation determinatio of aluminium,magnesium, and silicon in rocks,glasses, and pottery

A method for simultaneous neutron activation determination of Al, Mg and Si using two irradiations in a nuclear reactor—the first one with epithermal and the second one with pile neutrons is proposed. The applicability of the method is demonstrated by the analysis of standard reference materials—rocks, glass, as well as of archaeological finds from medieval glass and sgraffito ceramics.     

Interaction of benzene,L-histidine and L-proline with urea,N,N-dimethylpropyleneurea,and N,N-dimethylformamide in water

Russian Journal of General Chemistry - The paper focuses on the interaction of two heterocyclic amino acids and hydrophobic benzene with urea, dimethylformamide, and dimethylpropyleneurea in water...     

Kinetics of Sorption,Desorption, and Diffusion in Zeolites

Sorption and desorption in zeolites (molecular sieves) have to be considered as complex processes, involving simultaneous diffusion in zeolite crystals, mass transfer in the intercrystalline void of a pellet, and heat transfer between the zeolitic sorbent and its surroundings. The kinetics of sorption and desorption, respectively, of n-C₄H₁₀ in zeolite X and of CO₂ in zeolite A have been investigated: only the initial rates of uptake or release of the sorbet are controlled by mass transfer alone whereas ultimately they also depend on the rate of heat transfer from the sorbent to its surroundings or vice versa. Diffusivities of the sorbate in the zeolite crystals can be obtained from the kinetics of mass transfer, provided the resistance due to viscous or Knudsen flow between the crystals of the zeolitic sorbent can be eliminated. A sample consisting of a monolayer of single crystals had to be used for this purpose in the n-butane/zeolite X system; the intracrystalline diffusivity obtained in this way is not in conflict with data obtained by NMR spectroscopy. The intracrystalline diffusivities obtained in this way—taking into account the coupling of several processes during sorption — are higher than values reported in the literature.     

Determination of Arsenic,Cadmium, Cobalt,Chromium, Nickel,and Lead in Cosmetic Face-Powders: Optimization of Extraction and Validation

An analytical method for the quantification of toxic metals in face-powders is presented and discussed. Acid digestion with HNO₃-H₂O₂ or HNO₃-HCl was performed and compared with total digestion by HF. The digestion with HNO₃-H₂O₂ was the most suitable for these purposes. Analyses were performed by inductively coupled plasma atomic emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS), whose performances were compared by analyzing three different certified reference materials. The analysis of five commercial face-powders revealed the presence of all the considered metals in the range 0.06–8.0 µg/g. To simulate the bioaccessibility of metals in physiological conditions, a digestion with a simulated sweat solution was performed. In this case, the analysis of the same face-powder samples provided results below the limit of quantification, suggesting low bioaccessibility of the considered trace elements.