The electronic structure of heteroaromatic molecules; non-empirical calculations and photoelectron spectra for the isomeric-thiazoles and -thiadiazoles

The He(I) and MgKα photoelectron spectra are reported for the isomeric thiazoles, and He(I) spectra for the isomeric-thiadiazoles. Marked fine structure is apparent on some of the spectra. Comparison with the earlier spectra for thiophen and the azoles, and with ab initio calculations for the seven compounds, has led to assignment of the spectra. The calculations suggest that 1,3,4-thiadiazole is less aromatic than the other title compounds. As expected, the role of the 3d_s orbitals is found to be that of polarisation functions for all of the compounds, but inclusion of these orbitals leads to much better agreement with the observed dipole moments, both in magnitude and direction.     

硒对氟中毒大鼠尿氟及脑肾组织脂质过氧化物含量的影响

大鼠饲料分别加入２×１０－６、４×１０－６硒．饮用７．５×１０－６、１５×１０－６氟水．１个月后，随尿硒粪硒排量增加，尿氟排量也增高，以２×１０－６硒饲料排氟效果最佳．血浆中ＡＬＰ、ＧＯＴ、ＧＰＴ及ＬＤＨ等酶活性加硒组有不同程度的降低．随后两次增高氟水量重复试验，给以２×１０－６硒饲料，仍观察到尿氟排量增高．血中含硒酶谷胱甘肽过氧化物酶活性也有升高趋势，脑及肾中脂质过氧化物（ＬＰＯ）含量明显减少，病区患者服硒后，尿氟含量亦高于对照组．实验结果提示；１）硒能促使体内氟由尿中排出；２）降低某些组织ＬＰＯ含量；３）减少体内氟含量；４）预防和改善氟中毒某些临床症状。     

卡尔曼滤波分光光度法同时测定钢中钛和钼

本文采用卡尔曼滤波(KF)递推法,以苯基荧光酮-溴化十六烷基吡啶与钛,钼的显色体系同时测定钛和钼,同时以柠檬酸和抗坏血酸掩蔽干扰,并引入误差校正因子来校正加掩蔽剂后在所测波段范围内所造成的残余背景吸收,用于实际钢样分析,获得较满意的结果。     

硒与消化系统癌关系的探讨

据不同地貌、地质条件在30个县市按剖面、同步、随机取土壤样品372份．测定硒等微量元素含量．作等级相关分析显示。土壤硒含量与消化系统癌呈负相关关系．作相对危险度、剂量-效应及多因素分析,认为此负相关关系并非偶然现象．     

甲状腺机能亢进症头发锌、硒、钒、锂、锗5种微量元素的动态变化

测定了２４例甲亢治疗前后及３０例健康对照的头发锌、硒、钒、锂及锗的含量，发现未治疗的甲亢头发锌、硒、钒、锂及锗含量较对照组低，Ｚｎ、Ｓｅ、Ｌｉ、Ｇｅ，Ｐ＜０．００１，Ｖ，Ｐ＜０．０１．甲亢经６～１２周抗甲亢药物治疗后．头发中５种元素均较治疗前上升（Ｐ＜０．００１），且头发钒和锂含量治疗后已达到对照组水平，Ｖ，Ｐ＞０．２，Ｌｉ，Ｐ＞０．１，而头发锌、晒及锗含量治疗后仍低于对照组（Ｐ＜０　．００１）．结论：甲亢头发锌、硒、钒、锂及锗含量降低．经６～１２周抗甲亢治疗可使头发钒及锂含量恢复正常水平，而其余３种元素则可能需要更长时间的抗甲亢治疗才能恢复至正常水平。     

橙皮甙与橙皮甙铜配合物生物活性的比较研究

试验结果表明，橙皮甙配合铜离子后，其抗炎性水肿作用和对小白鼠的体胃肠平滑肌推进运动加强，但对家兔离体肠管平滑肌则起先抑制、后兴奋的作用，口服途径较注射橙皮甙铜配合物的抗炎作用降低，可能与口服后该配合物易在消化道被解离，影响了铜离子吸收有关。     

健康老年人与若干常量及微量元素的相关性研究

用原子吸收光谱法测定了７０例健康老年人、３０例健康成年人和３０例老年高血压病人血清中Ｃｕ、Ｚｎ、Ｆｅ、Ｍｎ、Ｃａ、Ｍｇ６种元素的含量．结果表明，健康老年人组与健康成年人组（对照组）相比，除Ｆｅ以外，Ｃｕ、Ｚｎ、Ｍｎ、Ｃａ、Ｍｇ均有显著性差异；与老年高血压病人组相比，除Ｍｇ以外，Ｃｕ、Ｚｎ、Ｆｅ、Ｍｎ、Ｃａ均有显著性差异．我们认为稳定的Ｃｕ／Ｚｎ比值及较高的血Ｍｇ水平是健康老年人未发生心血管疾病及糖尿病的重要原因之一，而高Ｃｕ、高Ｃａ及显著偏高的Ｃｕ／Ｚｎ比值，则是发生高血压的一个重要原因。     

亚临床肝性脑病患者的血清锌,铜含量的测定及临床意义

检测了３０例慢性活动性肝炎患者、３０例肝硬化患者、３０例亚临床肝性脑病患者血清中的铜、锌含量，并与正常对照组进行比较分析，探讨了微量元素铜、锌的血清含量改变及其影响因素，分析其临床意义。结果表明体内的铜锌含量与肝脏功能有密切的关系。在慢性活动性肝炎时，虽然肝脏功能有一定的损害，但由于肝脏的代偿能力强，铜，锌含量仍可保持在正常水平，而在肝硬化、亚临床肝性脑病时，铜锌明显降低，而铜锌含量的降低又导致机     

锶与间溴偶氮羧-m显色反应及其应用研究

本文报道锶与间溴偶氮羧-m的显色反应,在pH2.60～3.68时,常温下形成β型络合物,表观摩尔吸光系数为ε_(705)5=1.6×10~5L·mol~(-1)·cm~(-1),锶量在0～14μg/25ml范围内服从比耳定律,络合物组成Sr:R为1:2。     

Preparation and Surfactant Properties of Amino Acid-based Surfactants

Recently,therehasbeenagreatdealofinterestinbiosurfactants,i.e.,surthce-activecompoundsproducedbymicroorganisms'orisolatedenzymes'.BiosurthctantspossessanLlmberofpotentialadvantagesovertheirchemicallymanufacturedcounterparts,includinglowtoxicity',biodegradability,awidevarietyofpossiblestructuresandeaseofsynthesisti.olninexpensive.renewablerawmaterials.Consequently,biosurfactantsmayhaveimportantapplicationsinnumerousareas,suchasfoods,cosmetics,personal-careproducts.alldpharmaceuticalformulation…     

Simultaneous Reduction of Nitro Group and S-S Bond in Nitrodisulfides by Samarium Diiodide: A New Approach to Benzothiazolines

Asapowerfulandversatileone-electrontransferreductant,Sml,hasbeenappliedwidelyinorganicsynthesis'.OurpreviousworksonthereductionofnitrocompoundsandreductivecleavageofS-S,Se-Se,Te-TebondswithSml,'ledustoinvestigatethesimultaneousreductionofnitrogroupandS-SbondbySml,.Benzothiazolinesderivativesareimportantreagentsandusefulintermediatesinorganicsynthesisandpharmaceuticalchemistry.Forinstance,theycanbeusedasadditionagentsforphotographicemulsions",effectiveacaricides",antituberculousagents",lubr…     

硒的抗突变性作用与机体免疫功能的研究

研究了在三氯甲烷致突变性试验中加入硒的影响。结果显示硒能减少Ａｍｅｓ试验中三氯甲烷诱变的回变菌落数，能使小鼠骨髓嗜多染红细胞微核率和鳙鱼外周血有核红细胞微核率明显下降。并研究了硒在细胞免疫试验中的作用，结果显示硒能使正常鼠和荷瘤鼠的肺和脾的ＮＫ细胞活性提高，能促进其脾Ｔ淋巴细胞的增殖反应，还能增加外周血Ｔ淋巴细胞数。     

Oxidation of the Norditerpenoid Alkaloids Isotalatisidine and 6-Epiforsticine

Inpreviousworksonmodificationsofnorditerpenoidalkaloids,wereportedsomeimportantreactionssuchasN-deethylationandpreparationsoftheimmesand7,17-secoderivatives'.NowwewishtorepoFtoxidationofthenorditerpenoidalkaloidsisotalatizidineand6-epiforsticine.Oxidationofnorditerpenoidalkalnidshavinganla-hydroxylgroupwithreagentssuchasKMnO.K,Fe(CN),,OsO.,Ag,OandNBSaffordedcompoundswithanO,Nmixedacetalsystems=.Thus,treatmentofisqtalatizidineIwithKMnO.inacetone-H,O(5;1)forIhgavetheknowncompoundnevade…     

化学镀液中次磷酸根和亚磷酸根的离子色谱测定

在HPIC-AS4A分离柱上选用2.0×10~(-3)mol/L Na_2CO_3作淋洗液分离子微量HPO_3~(2-)和较高含量的H_2PO_2~-,用串联双电导检测器的不同输出范围分别同时定量。本法用于化学镀液中H_2PO_2~-和HPO_3~(2-)的测定,得到满意结果。     

微量元素缺乏症及其防治

报道了以235名健康小儿的血清锌、铜正常参考值及铜／锌比值作依据，对538名本地区集体儿童进行了调查．对240例不同病种患儿的血清锌、铜含量测定，并进行了分析；对G6PD、GSH-PX、AKP醇活性与微量元素含量的关系进行了相关性比较；对微量元素锌缺乏症的患儿进行了临床治疗观察；对微量元素缺乏症的防治进行了讨论．     

Photoresists comparative analysis using soft X-ray synchrotron radiation and time-of-flight mass spectrometry

Positive photoresists are widely used in lithographic process for the fabrication of relief components. When exposed to UV radiation they suffer chemical reactions modifying their chemical and physical properties. Aiming to follow molecular modifications among two different photoresists unexposed and previously exposed to ultraviolet light we have employed spectroscopic techniques coupled with mass spectrometry in the study of the AZ-1518 and AZ-4620 photoresists. The photon stimulated ion desorption (PSID) technique following the S K-edge NEXAFS spectrum was employed at the brazilian synchrotron light source (LNLS), during single-bunch operation and using time-of-flight mass spectrometry (TOF-MS) for ion analysis. NEXAFS and PSID mass spectra on both AZ-1518 and AZ-4620 photoresists (unexposed and exposed) were obtained and relative desorption ion yield curves determined for the main fragments as a function of the photon energy. They present marked different PSID spectra. Fragments related to the photochemical decomposition of the AZ-1518 photoresist could be clearly identified differently from the AZ-4620. Studies on the hardness of both photoresists were performed using O₂ plasma reactive ion etching (RIE) technique, analyzed by scanning electron microscopy (SEM) and used to explain different desorption yields in the PSID spectra. These results show that the PSID technique is adequate to investigate structural changes in molecular level in different unexposed and exposed photoresists, which is crucial for improving our knowledge about the breakup process.     

用无火焰原子吸收光谱测定家兔注射顺氯氨铂前后血清、肝、肾、肺、心组织中Pt含量

用无火焰原子吸收光谱测定家兔从肝动脉注射顺氯氨铂前后的血药浓度及在体内分布情况。     

Synthesis and crystal structure of a chiral lactam and three amino alcohols as potential protein tyrosine phosphates 1B inhibitors

Chiral lactam 2 and three chiral β-amino alcohols 3–5 have been synthesized and characterized by spectroscopic techniques. Regioselective ring opening reaction of chiral styrene oxide by an amine nucleophile was confirmed by X-ray diffraction data. Ligand 2–4 crystallizes in the tetragonal, orthorhombic and tetragonal crystal lattice system respectively. Ligands 2–6 have been used as potential inhibitors for protein tyrosine phosphatase 1B enzyme (PTP1B). The potential inhibitor effect of these molecules to the target protein was investigated by Dock and molecular dynamics calculations. Dock score analysis and Lipinski parameters suggested that ligands 1, 2, 4–6 are potential inhibitors towards PTP1B, thus indicating that the residues Arg24, Arg254 and Met258, Asp29 in the second active site of PTP1B are essential for the high selectivity of inhibitors. The results indicate that the polar hydrogen bonding interacts with Asp29, Gln102, and the amino acid residues of PTP1B are responsible for governing inhibitory potency of ligands 1–6.     

多波长线性回归法用于同时光度测定铁和铜

在弱酸性介质中,在乳化剂OP存在下,铁、铜与PAN形成最大吸收均在550nm处的水溶性有色络合物,两者相互严重干扰。本文采用多波长回归分析法对此混合显色体系进行研究,选择在570～590nm区间,测定11个波长处的吸光度,使用简易程序计算器,进行数据回归处理,可简便快速地直接求出铁、铜的含量。应用于铝合金中铁、铜的同时测定,结果满意。