ZrP-Nafion115复合膜的直接甲醇燃料电池原位稳定性

以商品Nafion115膜中的水合纳米离子簇为微反应器,通过化学键将磷酸氢锆(ZrP)纳米粒子锚合在Nafion115膜中,制备了ZrP-Nafion115复合膜。通过XRD及原位恒流放电等方法研究了复合膜在直接甲醇燃料电池(DMFC)工况条件下的稳定性,并进一步揭示了ZrP在Nafion115膜中发生化学锚合作用的反应机理及微观结构。结果表明:使用了ZrP-Nafion115复合膜的DMFC在恒流放电(100 mA/cm~2)过程中,可以在0.4 V以上的电压中稳定运行至少116 h,且ZrP纳米粒子没有明显流失。     

直读光谱法测定铸铝115中硅铁镁锌铍

铝合金中化学成分测定常用比色法 [1,2 ]与滴定法 [1] ,这两种方法样品消耗量大 ,且需将样品转化成溶液 ,样品处理工作量大 ,预处理过程繁琐 ,耗时多 ,而且所用化学试剂多 ,化验成本偏高。光谱分析速度快 ,准确度高 ,单个样品从接样到报出结果所需时间不超过 1 0 min,是一种金属化学成分测定的快捷方法。但光谱分析对标准样品要求比较高 ,铸铝 1 1 5材料须分析硅、铁、镁、锌、铍五个元素 ,目前市场上的标样不能覆盖该材料 ,因此需要两套标样 ,本文采用ZLD1 0 1、LC4两套标样 ,用自制的控制试样 ,采取控样法分析铸铝 1 1 5样品 ,消除了因…     

Multi-residue determination of 115 veterinary drugs and pharmaceutical residues in milk powder,butter, fish tissue and eggs using liquid chromatography–tandem mass spectrometry

A simple and sensitive multi-residue method for the determination of 115 veterinary drugs and pharmaceuticals, belonging in more than 20 different classes, in butter, milk powder, egg and fish tissue has been developed. The method involves a simple generic solid–liquid extraction step (solvent extraction, SE) with 0.1% formic acid in aqueous solution of EDTA 0.1% (w/v)–acetonitrile (ACN)–methanol (MeOH) (1:1:1, v/v) with additional ultrasonic-assisted extraction. Precipitation of lipids and proteins was promoted by subjecting the extracts at very low temperature (−23 °C) for 12 h. Further cleanup with hexane ensures fat removal from the matrix. Analysis was performed by liquid chromatography coupled with electrospray ionization and tandem mass spectrometry (LC-ESI-MS/MS). Two separate runs were performed for positive and negative ionization in multiple reaction monitoring mode (MRM). Particular attention was devoted to extraction optimization: different sample-to-extracting volume ratios, different concentrations of formic acid in the extraction solvent and different ultrasonic extraction temperatures were tested in butter, egg and milk powder samples. The method was also applied in fish tissue samples. It was validated, on the basis of international guidelines, for all four matrices. Quantitative analysis was performed by means of standard addition calibration. For over 80% of the analytes, the recoveries were between 50% and 120% in all matrices studied, with RSD values in the range of 1–18%. Limits of detection (LODs) and quantification (LOQs) ranged from 0.008 μg kg⁻¹ (oxfendazole in butter) to 3.15 μg kg⁻¹ (hydrochlorthiazide in egg). The evaluated method provides reliable screening, quantification, and identification of 115 veterinary drug and pharmaceutical residues in foods of animal origin and has been successfully applied in real samples.     

兑制白酒引起115例甲醇中毒的调查分析

为了总结广州市首宗群体性假酒中毒案的救治经验,给今后指导制订应对公共卫生突发事件的应急方案提供参考依据,对饮用甲醇含量超标的散装白酒引起中毒的115例中毒者的流行病学调查资料进行了分析。将2004年5月11日至5月28日发生在广州市某区甲醇中毒事件中入院和在家死亡的确诊病例,根据其病情轻重分为4类:死亡14例,重度中毒21例,轻度中毒12例,观察病例68例。资料采用秩和检验和等级相关分析的统计学处理方法。结果表明,发病平均潜伏期为4.44 d。死亡病例和重度中毒病例平均潜伏期明显比观察病例短,有显著性差异(P<0.05)。血液中甲醇平均浓度为3.90 mmol/L。剩余酒中甲醇平均含量106.1 g/L,死亡病例和重度中毒病例剩余酒中甲醇平均含量明显高于观察病例,有显著性差异,P<0.05。病情轻重与饮酒总量间有非常显著性差异(P<0.000 1)。提示甲醇中毒潜伏期短,来势凶猛,第一例病例的确诊和及时上报,及时进行流行病学调查,采集病人剩余酒样本进行检验,对及时控制群体性假酒中毒事态的发展尤为重要。     

Nafion115膜的溶解及其再铸膜性能测定

利用二甲基亚砜将质子交换膜燃料电池用过的Ｎａｆｉｏｎ1 1 5膜在二甲基亚砜沸点温度 ,常压下溶解 ,得到了含Ｎａｆｉｏｎ树脂为 2 %左右的溶液 ,并在 1 70℃条件下再铸成膜。利用ＸＲＤ、交流阻抗和燃料电池等对膜的性能进行了评价和分析。结果表明 ,再铸膜的分子结构、电阻、交换容量、吸水量以及伏 安性能均与相同厚度的Ｎａｆｉｏｎ1 1 5接近。Ｐｅｒｆｌｕｏｒｉｎａｔｅｄｒｅｓｉｎｓｏｌｕｔｉｏｎｉｓｕｓｅｆｕｌｉｎｐｒｏｔｏｎｅｘｃｈａｎｇｅｍｅｍｂｒａｎｅｆｕｅｌｃｅｌｌ.Ａｔｔｈｅｔｅｍｐｅｒａｔｕｒｅｏｆｂｏｉ…     

Ni(115)台阶面对氢表面微观动力学行为的影响

用５参数Ｍｏｒｓｅ势模拟氢－镍表面体系相互作用势，考察了氢原子在Ｎｉ（１１５）台面上吸附扩散行为。同时构造了氢分子与Ｎｉ（１００）和Ｎｉ（１１５）台阶面 相互作用推广的ＬＥＰＳ势面面，考察了氢分子解离化学吸附的微观动力学性质。     

超高效液相色谱-串联质谱法同时测定血液中115种农药

建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)一针进样同时测定血液中115种农药的方法。血液样品与提取剂甲醇按1∶5体积比进行蛋白沉淀,涡旋振荡2 min,以12 000 r/min离心10 min,取上清液进行UPLC-MS/MS分析。质谱分析采用电喷雾离子源(ESI),正离子模式和负离子模式同时切换采集。结果表明,115种目标农药在1～200 ng/mL质量浓度范围内线性关系良好(r0.99),13%的目标农药检出限(S/N≥3)为0.2 ng/mL,其余目标物均为0.1 ng/mL,所有目标农药的定量下限(S/N≥10)均为1 ng/mL。在10、50、100 ng/mL加标水平下,方法的基质效应为81.8%～115%,目标农药的回收率为80.4%～109%,日内精密度(Intra-RSD)为1.6%～11%,日间精密度(Inter-RSD)为1.9%～13%。该方法简便快速、灵敏度高、稳定性好,适用于血液样品中多农药的定性定量分析。     

SYNTHESIS AND CRYSTAL STRUCTURE OF 5, 10, 15, 20, 22, 24-HEXAHYDRO-5, 5, 10, 10, 15, 15, 20, 20-OCTAMETHYL-PORPHINE

<正> The title com pound (HHOMP) has been synthesized with the pho-toinduced condensation of acetone and pyrrole in the presence of iodoaromatic hydrocarbons, and its molecular and crystal structures have been determined by X-ray analysis. C28H36N4, Mr = 428. 63, triclinic; space group P1; a =10. 165(3), b = 10. 185(2), c=13. 012(3)(?); α=85. 41(2), β=67. 84(2), γ= 89. 75(2)°; V = 1243 (?)3; Z = 2; D = 1. 145g. cm-3; μ= 0. 635cm-1; F (000) = 464. Although the HHOMP molecule twists, it is found that the four nitrogen atoms are still in a plane.     

在小硅化物SiX^m4（X=H,He,Li,Be,O,F,Ne,Na,Mg,S,Cl,Ar;m=0,…

用从头算方法，在ＨＦ／ＳＴＯ－３Ｇ、ＨＦ／３－２１Ｇ和ＨＦ／６－３１Ｇ水平上研究了小硅化物ＳｉＸ＾ｍ４的成键倾向性。计算结果表明，所研究的分子势能曲线均有稳定的极小值（ＳｉＬｉ４除外）。与已知的稳定分子ＳｉＨ１、ＳｉＦ４和ＳｉＣｌ４比较，含惰性元素的未知分子ＳｉＨｅ＾４＋４、ＳｉＮｅ＾４＋４和ＳｉＡｒ＾４＋４比含碱金属和碱土金属的未知分子ＳｉＬＩ４、ＳｉＮａ４、ＳｉＢｅ＾４＋４和ＳｉＭｇ＾４＋４有     

Theoretical Study on the Structure and Stability of Si5X （X = Li, Be, B, C, N, O, F, Na, Mg, Al, Si, P, S, Cl） Clusters

1 INTRODUCTION In the later 60s of last century, silicon substituted for germanium to present as mainstream in semicon- ductor. The semi-conductive devices made by silicon have many advantages, for example, refractory pro- perty, high radioresistance, simple and stable process- ing technic, high machinability and low cost. So it was widely used to manufacture large power appara- tuses, for instance, digit and linear integrated circuit, large scale integrated circuit (LSI), etc. Thus, th…     

急性心肌梗塞患者血清硒,锌,铜,钙,镁,铁,锶含量的测定

分别对２９例急性心肌梗塞（ＡＭＩ）病人和４０例健康人进行血清中七种微量、常量元素含量测定，结果表明，ＡＭＩ患者血清Ｓｅ、Ｚｎ、Ｃａ较正常对照组明显降低；血清Ｃｕ显著增高，血清Ｆｅ、Ｍｇ较对照组低，差异不显著；血清Ｓｒ两组无差异。对ＡＭＩ患者与血清硒及各元素间相互关系进行了探讨，指出调整人体微量、常量元素的不平衡状况，对冠心病和ＡＭＩ的发生、发展和康复有一定的临床意义。     

硫酸镍中Ca,Mg,Cu,Fe,Pb,Zn的光谱测定

用发射光谱法测定结晶硫酸镍中Ｃａ,Ｍｇ,Ｃｕ,Ｆｅ,Ｐｂ,Ｚｎ等杂质元素,加入ＮａＣｌ为缓冲剂改善杂质元素的激发行为,以提高分析的灵敏度。用交流电弧激发,以镍为内标,一次摄谱,可同时测定上述六种元素。此法快速、准确,满足实际需要。     

Die extraktive Abtrennung von Metallspuren (Hg, Ag, Pb, Cu, M, Co, Zn, Cd, Bi, Mn) in Silicatmineralien mit Natriumdi?thyldithiocarbamidat

Ohne Zusammenfassung     

ICP—AES法测定钢铁样中硅,磷,锰,铬,镍,铜,铝

详细地研究了钢铁样中主量铁对７种被测定元素的干扰和被测定元素间的干扰情况，并研究了不同酸分解样品的效果，确定了用电感耦合等离子体发射光谱测定钢铁样中硅、磷、锰、铬、镍、铜和铝的方法。