MoO_3、NiO、ZnO在小表面金红石上的分散行为

氧化物、盐类在氧化物载体表面的自发分散是一种广泛存在的现象，文献中已报导过大量氧化物和盐类在高比表面载体上分散的研究结果［'－3］TIO。作为一种较新型的载体，与Y－AI。O。、硅胶等传统载体相比，有许多不同特性．活性组分在TIO。表面的分散状态及所得催化剂的性能已有不少报导［'－'］，但所用的TIOZ主要是较高比表面的锐钛矿型TIOZ（刘金红石型TIO。（r）和锐钛矿型TIOZ（a）的结构不同，它是高温生成相，比表面较小［'］．氧化物在金红石上的分散行为仍未见报导．我们制备了三种具有不同比表面的TIO水），系统地研…     

C1/Ag(111)体系研究 Ⅳ.氯吸附对甲醇吸附氧化的影响

运用HREELS技术对甲醇在预吸附氯的Ag(111)表面上的吸附氧化行为进行了较细致的研究.结果证明Cl对甲醇氧化的影响缘于它在Ag(111)上的吸附所引起的表面结构的改变进而改变表面氧吸附物种,从而使得甲醇氧化的中间产物发生变化.实验结果说明甲醇在Ag(111)和低暴露量氯吸附的Ag(111)表面上的氧化行为是相似的,检测到了中间产物Ⅰ和Ⅲ;在高暴露量氯吸附的Ag(111)上甲醇氧化时则产生中间产物Ⅰ、Ⅳ和甲醛物种.对上述不同的甲醇氧化行为作了分析,并指出了以前人们在考察甲醇氧化机理时只考虑原子氧作用的片面性.     

双环[3.3.0]-3,7-辛二烯-2,6-二酮晶体的分子结构

利用 Enraf-Nonius CAD4四圆单晶衍射仪测定了双环[3.3.0]-3,7-辛二烯-2,6-二酮(2)的单晶结构,晶体属三斜晶系,空间群为 PI,晶胞参数为:a=6.596(2)(?),b=7.414(1)(?),c=7.359(1)(?),α=106.64(1)°,β=100.17(1)°,γ=98.44(1)°,ν=331.9((?)~3),Ζ=2。用直接法得到分子的粗结构。对1013个可观察反射点用全矩阵最小二乘法修正,最后得R=0.060,结构测定的结果证实:两个五员环自成一个平面,两平面间夹角为117.3°。     

功能化程序对笼形聚偕氨肟树脂吸附和吸留性质的影响

聚丙烯颗粒在水溶液中与丙烯腈和二乙烯基苯反应,得接枝交联产物（Ⅰ）。Ⅰ被氨肟化再经成笼反应．得笼形聚偕氨肟树脂（Ⅱ）。笼内仅吸留易于除去的溶剂丙酮。若Ⅰ成笼后再氨肟化,所得吸收剂（Ⅲ）将吸留大量的羟胺,它缓慢地释放出来,干扰吸收剂对酸、碱离子或分子吸附容量的测定。Ⅱ对一些离子例如Hg2+和MnO4-的吸附能力与Ⅲ不同,被认为是两者的网络结构不同所致。     

A nonlinear regression model applied to kinetic studies of ester hydrolysis with a surface acoustic wave sensor

A non-linear regression model was derived for the simultaneous determination of the rate constant in alkaline hydrolysis of esters and the initial concentration of esters based on the linear relationship between the frequency response of the surface acoustic wave sensor system and the conductivity of the solution. The model was tested theoretically and experimentally with the methyl-, ethyl-, and n-propyl-acetate systems. The corresponding rate constants estimated at 25 degrees C are 0.147, 0.103 and 0.0671 respectively.     

Silver nanocomposite layer-by-layer films based on assembled polyelectrolyte/dendrimer

Silver nanocomposite multilayer films were prepared through the in situ method. Multilayer thin films, prepared through the sequential electrostatic deposition of a positively charged third-generation poly(amidoamine) dendrimer (PAMAM) and negatively charged poly(styrenesulfonate) (PSS) and poly(acrylic acid) (PAA), were utilized as nanoreactors for the formation of silver nanoparticles. The silver ions were preorganized in layer-by-layer (LBL) films composed of PAMAM dendrimers and subsequently reduced with hydrogen to prepare the silver nanoparticles. The UV-vis spectrum and profilometer were used to characterize the regular growth of bilayers. UV-vis absorption from plasmon resonance at 435 nm and TEM images indicated the formation of the silver nanoparticles in the multilayer films. The silver nanocomposite LBL films were also constructed on the indium tin oxide-glass and investigated using cyclic voltammetry. The silver nanoparticles in the multilayer films have a stronger negative redox potential. The silver nanocomposite LBL films may have a potential application in the catalysis of reduction of 4-nitrophenol with sodium borohydride.     

提高普通低碳钢冷镦性能的工艺研究

本文分析比较了普通低碳Q195钢与冷镦钢生产工艺、性能组织等情况,对武钢目前生产的Q195钢进了取样冷镦试验,并进行了不同的控冷工艺轧制试验.提出在武钢目前炼钢生产条件下,采用适当的轧制工艺,完全可以用普通低碳Q195钢代替部分铆螺钢.     

Determination of human IgG by solid-substrate room-temperature phosphorescence immunoassay based on an antibody labeled with nanoparticles containing rhodamine 6G luminescent molecules

Luminescent 50-nm silicon dioxide nanoparticles containing both types of rhodamine 6G (R; particles denoted R-SiO₂) were synthesized by the sol–gel method. In the presence of Pb(Ac)₂ as a heavy atom perturber the particle can emit the intense and stable room-temperature phosphorescence (RTP) signal of R on a polyamide membrane, with _ex^max/_em^max=470/635 nm for R. Our research indicates that the specific immune reaction between goat-anti-human IgG antibody labeled with R-SiO₂ and human IgG can be carried out quantitatively on a polyamide membrane, and the phosphorescence intensity was enhanced after the immunoreaction. Thus a new method for solid-substrate room-temperature phosphorescence immunoassay (SS-RTP-IA) for determination of human IgG was established on the basis of antibody labeled with the nanoparticles containing binary luminescent molecules. The linear range of this method is 0.0624–20.0 pg spot^–1 of human IgG (corresponding to a concentration range of 0.156–50.0 ng mL^–1, sample volume 0.40 L spot^–1). The regression equations of the working curves are I_p=71.27+7.208m_IgG (pg spot^–1) (r=0.9996). Detection limits calculated as 3S_b/k are 0.022 pg spot^–1. Compared with the same IA using fluorescein isothiocyanate (FITC) as the marker the new method was more sensitive and had a wider linear range. After elevenfold replicate measurement RSD are 4.5 and 3.6% for samples containing 0.156 and 50.0 ng mL^–1 IgG, respectively. This method is sensitive, accurate, and of high precision.     

LaC_3~n(n=-1,0,+1)分子簇的理论研究(英文)

用密度泛函方法研究了ＬａＣ３ｎ（ｎ＝－１，０，＋１）分子簇的结构和稳定性，对这个四原子体系，提出了５种可能构型，其中３种具有Ｃ２ｖ对称性，２种为Ｃ∞ｖ对称性．在Ｃ２ｖ对称性结构中，其中１个为Ｌａ接在弯曲的Ｃ３链上，第２个是Ｌａ通过２个键与Ｃ３环相链，第３个是Ｌａ通过１个键与Ｃ３环相连；在Ｃ∞ｖ对称性中，第１个Ｌａ接在Ｃ３链的一端，而在第２个构型中，Ｌａ被插入在Ｃ３链中．结果表明，环状结构当Ｌａ接在弯曲的Ｃ３链上的是局域极小值并且最稳定     

混合配体、希土三元配合物的研究 Ⅳ.3,5—二硝基水扬酸(H_2DNSA)、邻菲咯啉(phen)、希土(RE)三元固体配合物的合成及性质

本文报道了十种希土元素与3,5-二硝基水扬酸、邻菲咯啉三元配合物的制备方法。通过元素和化学分析测定了化合物的化学组成,并用红外光谱、紫外光谱、差热分析、磁化率、X射线粉天衍射等对所合成的化合物进行了结构和性质的研究。