应用水解还原铁(Ⅲ)-邻二氮菲光度法测定丙酮肟

丙酮肟在酸性条件下经加热水解生成具有还原性的羟胺,并将Fe(Ⅲ)定量还原为Fe(Ⅱ),应用Fe(Ⅱ)-邻二氮菲光度法简接测定丙酮肟。选择了水解最佳条件(加热温度、时间、介质酸度、显色剂的加入顺序等),结果表明,测定线性范围为0～1.2mg/L,相关系数r=0.9998,最低检测浓度为0.046 mg/L,RSD<3.3％(n=5)。应用该法测定火力发电厂锅炉运行水中丙酮肟的含量,方法简便,灵敏度高。     

金属氧化物对铁系催化剂在CO变换反应中的稳定性和活性的影响(英文)

铁系催化剂一直是合成氨及制氢工业中一氧化碳变换反应最常用的催化剂。运用X射线衍射（XRD）、程序升温还原（TPR）及活性评价技术研究了添加金属氧化物对铁系催化剂的晶相结构、催化剂的稳定性和催化活性的影响。结果表明,不同的金属氧化物对催化剂结构的稳定作用和活性影响不同,其中CeO2和Bi2O3都能增强铁系催化剂的稳定性,提高催化剂的活性。     

聚苯乙烯三乙醇胺树脂的合成与表征

由氯甲基聚苯乙烯与三乙醇胺反应合成了聚苯乙烯三乙醇胺树脂,通过元素分析,交换容量,溶胀性和ＩＲ对其进行表征,研究了其可能结构和某些性能。     

An analytical solution for the elastic fields near spheroidal nano-inclusions

When the size of an inclusion shrinks to nanometers, interface energy plays an important role in the deformation around it. In the present paper, we consider the effect of interface energy on the elastic fields near a spheroidal nanoinclusion embedded in an elastic medium on the basis of surface elasticity theory. Using Boussinesq-Sadowsky potential function method, we obtain the deformation field near the inclusion subjected to a uniformly uniaxial loading at infinity. The results show that the elastic fields near the nano-inclusion depend strongly on the interface properties, the size and shape of inclusion. These new characteristics may be helpful to understand various relevant mechanical performances of nanosized inhomogeneities.     

A new immersed boundary method for compressible Navier–Stokes equations

This paper presents an immersed boundary method for compressible Navier–Stokes equations in irregular domains, based on a local radial basis function approximation. This approach allows one to define a reconstruction of the radial basis functions on each irregular interface cell to treat both the Dirichlet and Neumann boundary conditions accurately on the immersed interfaces. Several numerical examples, including problems with available analytical solutions and the well-documented flow past an airfoil, are presented to test the proposed method. The numerical results demonstrate that the proposed method provides accurate solutions for viscous compressible flows.     

Nickel(II) Complexes of N‐Alkyl‐Substituted Diamino Diamides in Aqueous Solution

In order to study the steric, inductive, and ring‐strain effects of diamino diamides on the equilibrium and spectral properties of nickel(II)‐diamino diamides complexes, four tetradentate ligands, 4‐methyl‐4,7‐diazadecanediamide(4‐Me‐L‐2,2,2), 4,7‐dimethyl‐4,7‐diazadecanediamide(4,7‐N,N'‐Me₂‐L‐2,2,2), 4‐ethyl‐4,7‐diazadecanediamide (4‐Et‐L‐2,2,2), and 4‐methyl‐4,8‐diazaundecanediamide (4‐Me‐L‐2,3,2), have been synthesized. Their protonation constants have been determined potentiometrically in 0.1M KCl at 25.0°C The formation of their nickel(II)‐complexes and the Ni‐O to Ni‐N bond rearrangements at the two amide sites of these complexes have been investigated quantitatively by potentiometric and spectrophotometric techniques under the same conditions. Electronic spectra of the nickel(II)‐complexes of these ligands and their deprotonated species formed in aqueous solution were measured and discussed.     

微波消解-电感耦合等离子体质谱法测定稻谷中铬、镍、铜、砷、镉、铅的含量

通过对测定元素质量数和内标元素的选择,并对存在的干扰进行校正,采用电感耦合等离子体质谱(ICP-MS)法测定大米中铬、镍、铜、砷、镉、铅的含量。各元素测定值的相对标准偏差RSD(n=6)在0.61%～2.2%,加标回收率在92.8%～108%。用来测定标准物质GBW 10011、GBW10022、GBW(E)100348、GBW(E)100361,各元素的测定值与标准值一致,能够满足大米中重金属元素的测定要求。     

Photolithography-free fabrication of photoresist-mold for rapid prototyping of microfluidic PDMS devices

Traditional soft lithography based PDMS device fabrication requires complex procedures carried out in a clean room. Herein, we report a photolithography-free method that rapidly produces PDMS devices in 30 min. By using a laser cutter to ablate a tape, a male photoresist mold can be obtained within 5 min by a simple heating-step, which offers significant superiority over currently used photolithographybased method. Since it requires minimal energy to cut the tape, our fabrication strategy shows ...