Novel Oxygen Storage Components Promoted Palladium Catalysts for Emission Control in Natural Gas Powered Engines

A three-way catalyst comprised novel oxygen storage components for emission control in natural gas powered engines was prepared. The addition of novel oxygen storage components to the Pd/γ-Al2O3 catalysts resulted in improved activities of the fresh and aged catalyst by lowering the light-off temperature for methane in natural gas engines exhaust.     

2-羟基-3-羧基-5-磺酸基苯基重氮氨基偶氮苯吸光光度法测定微量钯

于pH9.3～10.6Na_2CO_3-NaHCO_3缓冲介质中,在Triton N-101存在下,Pd(Ⅱ)与2-羟基-3-羧基-5-磺酸基苯基重氮氨基偶氮苯(HCSDAA)形成组成比为1:2的红色配合物,其最大吸收波长为530nm,表观摩尔吸光系数为1.05×10~5,线性范围为0～0.7μg·ml~(-1) .结合丁二酮肟螯合,氯仿萃取,方法用于贵金属二次合金中微量钯的测定,相对标准偏差为2.0%(n=6).加标回收率为93.8%～99.3%.     

超临界流体萃取及其在我国的研究应用进展

本文综述了近年来国内外超临界流体萃取的研究应用概况, 着重介绍了我国这一新技术在基础理论、应用及工艺方面的进展。     

(四氮杂十四元大环)·双(O，O′-二(1-萘基)二硫代磷酸根)合镍或铜的合成与谱学性质

Four new nickel and copper complexes ［ML{SSP(OC₁₀H₇-1)₂}₂］, where M=Ni(Ⅱ), Cu(Ⅱ); L=5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene(hmtade) or 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane(hmta); SSP(OC₁₀H₇-1)₂=O,O′-bis(1-naphthy)dithiophosphate, were synthesized and characterized by elemental analysis, molar conductivity, infrared spectra, electronic spectra and TG-DTA thermal analysis. The complexes are non-electrolytes in DMSO. O,O′-bis(1-naphthyl) dithiophosphate ligand that behaves in monodentate fashion coordinates to metal ion.     

5‘—硝基水杨基荧光酮双波长标准加入分光光度法同时测定？…

在０．３－０．９ｍｏｌ／Ｌ硫酸介质中，在溴化十六烷基三甲铵存在下，５’－硝基水杨基荧光酮与锗和钼形成最大吸收波长分别为５１３和５３３ｎｍ的红色配合物，其吸收光谱严重重叠。基于此，本文采用双波长标准加入法对该混合物的显色体系进行了研究，建立了同时分光光度测定锗和钼的新方法，并与等吸收双波长法作了比较。     

甲基红共振瑞利散射法测定肝素钠

肝素钠（Hep）系葡糖胺聚糖，是蛋白多糖的一种，它具有广泛的生物学功能，是重要的生化药物之一。对不同的疾病，有不同的最适剂量，临床上需进行监控。因此，研究肝素的定量测定方法是非常重要的。肝素的测定最常采用的是生物方法。此外，化学方法有分光光度法、HPLC法，毛细管电泳法，电化学传感器。在国内外利用共振瑞利散射测试肝素钠的也有报道，一般都采用了稀土高价阳离子作增色剂。本文采用的是一种价格便宜的甲基红（methylred）染料作增色剂，结果表明：在近中性的B—R缓冲溶液中，肝素钠与甲基红染料形成离子缔合物后，RRS强度显著增强，并产生了新的RRS光谱；且在一定范围内，RRS强度与肝素钠浓度成正比。在0．060μg/mL～4．00μg/mL范围内呈良好的线形关系，由此对肝素钠注射液进行效价分析，并用此方法测定人体血清中的肝素钠含量，测得人体血清中肝素钠含量为9．18mg／100mL，回收率在90％以上。显然，此法对肝素钠的测定是可靠、灵敏而实用的。     

Preparation of Pt/K_2La_2Ti_3O_(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

1 Introduction Conventional energy resources, such as coal, petro-leum products, etc., which are fulfilling most of the world’s energy requirement have been depleted to a great extend. The human being is now facing exhaus-tion of fuel resources in a near…     

两个噻吩并萘并吡喃类化合物的合成及结构表征

以2,7-萘二酚为原料分别经六步反应合成了两个新的角型噻吩并萘并吡喃化合物6和8。两个目标化合物及所有新中间体的结构均经^1HNMR、MS、IR、元素分析充分表征。测定了化合物6的单晶分子结构,其特殊的分子平面刚性和α-吡喃与噻吩部分的活泼双键间的空间结构使之成为更有效的单官能团DNA嵌入剂。     

Preparation of Pt/K2La2Ti3O10 and its photo-catalytic activity for hydrogen evolution from methanol water solution

A layered perovskite-type oxide K₂La₂Ti₃O₁₀ was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K₂La₂Ti₃O₁₀ as a co-catalyst with different methods. The dispersion of platinum on K₂La₂Ti₃O₁₀ was determined with HOT method. The photocatalytic activity of Pt/K₂La₂Ti₃O₁₀ was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K₂La₂Ti₃O₁₀. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 233.88 μmol·h⁻¹ by Pt(2%)/K₂La₂Ti₃O₁₀. A possible band structure and mechanism were discussed based on the results.     

ZnS:Co2+晶体顺磁g因子的理论研究

提出了一个计算二元半导体中过渡金属(TM)离子顺磁g因子的共价模型,并用以计算了ZnS:Co²⁺晶体的g因子,计算值与实验值吻合很好,从而解决了用经典方法得到的g因子值与实验值相比偏小的问题.同时,通过对ZnS:Co²⁺晶体晶场光谱和顺磁g因子的分析,本文建议,在ZnS:Co²⁺晶体中,Co²⁺离子的t_2g电子和e_g电子部分处于反键轨道部分处于成健轨道.