Ni基六铝酸镧LaNiAl11O19催化剂表面甲烷CO2的重整积炭速率

甲烷二氧化碳重整制合成气反应过程中,催化剂表面积炭是制约催化反应顺利进行的关键因素。研究催化剂表面积炭物种及积炭速率,找出影响催化剂表面积炭的动力学因素,对建立合理的催化重整反应体系,完善催化剂表面积炭的动力学理论具有重要的理论和实际意义。目前有关催化剂表面积炭速率的研究报道较少[1,2]。Ｎｉ基六铝酸盐催化剂对甲烷二氧化碳重整制合成气具有很好的催化活性和稳定性[3,4]。本文利用Ｘ 射线光电子能谱(ＸＰＳ)和热重分析(ＴＧＡ)技术,在还原态Ｎｉ基六铝酸镧ＬａＮｉＡｌ11Ｏ19催化剂表面研究了甲烷裂解积炭和甲烷二氧…     

Studies on the Model Synthesis of the Brassinolide and Dolicholide‘s Side Chains

A highly stereoselective synthesis of the side Chain enantiomers of brassinolide and dolicholide through an aldol reaction of 2-(4-methoxy benzyloxyl) proplonylaldehyde (5) with the anion of 1- ( tert -butyldimethylsiloxy )-3-methyl-2-butanone ( 6 ) is described.     

不同尺度和分散状态的钯纳米粒子红外光学性能研究

运用CO分子探针红外光谱研究不同尺度和分散状态的钯纳米粒子的红外光学性能.结果表明,粒子尺度为6.6nm分散的球型钯纳米粒子(Pdn)和粒子尺度为100～150nm分散的立方体型钯纳米粒子(Pdncube)均给出两个不同吸附方式的桥式CO红外谱峰,其吸收峰位置约在1970cm-1和1910cm-1.将Pdn引入到电极表面后,通过界面电化学诱导使之形成团聚体(Pdnag),其红外光学性能发生显著变化,表现为随着界面电化学诱导时间的增加,其1970cm-1处的谱峰方向从正常转为异常.本研究进一步证明红外谱峰方向的倒反是由于粒子间的相互作用引起的.     

玻璃管负载纳米TiO2薄膜的制备及其对乙烯降解的研究

采用sol—gel技术，在细玻璃管表面制备了La掺杂复合TiO2薄膜，采用封闭循环装置考察了催化剂负载质量、镧掺杂量、热处理温度和湿度等因素对催化活性的影响．结果表明，随着薄膜层数的增加，乙烯降解率增加，UV-VIS在近紫外的吸收随层数的变化与之吻合；镧掺杂量为1.5％、热处理温度500℃催化剂活性最高，而湿度的增大有利于提高乙烯的降解率和降解速度．     

淮山药及其种植土壤中微量元素的测定

用等离子体原子发射光谱(ICP-AES)测定了淮山药根茎及其种植土壤中的微量元素。结果表明,淮山药中含有丰富的人体必需微量元素,为淮山药产品的研究和开发提供重要的依据,也为进一步开发淮山药优良品种和平衡施肥提供科学信息和依据。     

Theoretical Studies on Electronic Spectra and Second-order Nonlinear Optical Properties of Barbituric Acid Derivatives Substituted with Schiff Base

Barbituric acid (BA) is a very important kind of compound in biological chemistry and medicine. It can be applied in abirritative medicine and antioxidants.1 It is an important sort of raw material for organic synthe-sis.2 It predicts the important reactive mechanism for organic synthesis.3 Some investigations for NLO prop-erties of a series of BA derivatives have been reported by Feng and coworkers in the view of theory.4,5 The Schiff base has extensive application in the fields of organi…     

Spectroscopy Investigation on Conformational Transition of Tea Glycoconjugate from Green Tea

The conformational transition of a new glycoconjugate, tea glycoconjugate (TGC), was investigated by spectroscopy techniques including circular dichroism (CD) and ultraviolet (UV) spectroscopy. The solution behaviors of TGC in the mediums of different temperature, pH value, and ions were compared. Results showed that the native conformation of TGC was partially ordered. The CD value and UV absorbance of TGC altered with the change of pH value, temperature, the addition of ions, and also accompanied order-disorder transition. Especially the conditions with temperature higher than the glass transition temperature (Tg=62℃), higher pH value or lower pH value will have the most impact on the conformation of TGC, which will destroy the hydrogen bonds between the TGC molecules. The results indicated that the outside factors play important roles on the stability of the conformation of TGC.     

7,3′-二甲氧基-4′,5′-次乙二氧基黄烷酮的合成

以香草醛和问苯二酚为原料,经7步反应合成了新的苯并二氧六环新木脂素黄酮类似物7,3′-二甲氧基-4′,5′-次乙二氧基黄烷酮,总收率16．1％,其结构经^1H NMR,IR和MS证实。     

有机过氧化物的热自燃性小药量评价法

有机过氧化物的热自燃性小药量评价法;有机过氧化物;热自燃危险性;自加速分解温度;微量量热仪     

反相流动注射-化学发光法测定苯胺

在酸性介质中,苯胺与过量亚硝酸盐重氮化,剩余亚硝酸盐快速氧化亚铁氰化钾,生成的铁氰化钾与鲁米诺发生化学发光反应。据此,建立了反相流动注射 化学发光法测定苯胺的新方法。方法的线性范围为0 070～10.0mg L,检出限为0 03mg L,相对标准偏差(n=11,ρ=1.0mg L)为2 0%。方法已用于环境水样中苯胺的测定。