Effect of pH on the Interaction of Gold Nanoparticles with DNA and Application in the Detection of Human p53 Gene Mutation

Gold nanoparticles (GNPs) are widely used to detect DNA. We studied the effect of pH on the assembly/disassembly of single-stranded DNA functionalized GNPs. Based on the different binding affinities of DNA to GNPs, we present a simple and fast way that uses HCl to drive the assembly of GNPs for detection of DNA sequences with single nucleotide differences. The assembly is reversible and can be switched by changing the solution pH. No covalent modification of DNA or GNP surface is needed. Oligonucleotide derived from human p53 gene with one-base substitution can be distinguished by a color change of the GNPs solution or a significant difference of the maximum absorption wavelength (λ_max), compared with wildtype sequences. This method enables detection of 10 picomole quantities of target DNA.     

Effect of the solvent on growth of titania nanotubes prepared by anodization of Ti in HCl

The effect of the solvent on the anodic growth of titania nanotubes in HCl dissolved in water, ethylene glycol and 2-propanol was studied. These nanotubes grow with locally rapid breakdown of the passive TiO₂ film forming a forest of nanotubes-bearing microtowers with the background of passive TiO₂ Film. These bundles of assembled-groups of titania nanotubes look like Pillars corals. The low relative permittivity of the 2-propanol led to lowering of dissociation of HCl and hence lowering the activity of H⁺ and Cl⁻ ions which in turn led to suppress of dissolution of titania and increasing the growth rate of the titania nanotubes. The X-ray diffraction pattern showed that the titania nanotubes after annealing change to the crystalline anatase phase. The anodic films showed characteristic coloration with intensity and color that changes (qualitatively) with time of anodization.     

Some crown ethers as inhibitors for corrosion of stainless steel type 430 in aqueous solutions

The effect of crown ethers on the corrosion behavior of stainless steel (type 430) in 2M HCl solution was studied using weight loss and galvanostatic polarization methods. The inhibition efficiency was found to increase with increasing the concentration of the inhibitors and deceases with increasing the temperature. The polarization studies showed that crown ethers act as mixed-type inhibitors. The inhibiting effect of these compounds was interpreted in view of their adsorption on the metal surface. The adsorption of these compounds was found to obey Temkin adsorption isotherm. Surface examination and morphological studies were tested using scanning electron microscope (SEM) and energy dispersive X-ray (EDX). All the results achieved were compared and discussed.     

Effect of HCl concentration on the sintering behavior of 8 mol% Y2O3 stabilized ZrO2 deposits produced by electrophoretic deposition (EPD)

In this work, we have investigated the effect of HCl concentration and particle packing on the sintering behavior of 8 mol% yttria-stabilized-zirconia (8YSZ) deposits. 8YSZ deposits were fabricated by electrophoretic deposition (EPD). For 8YSZ coatings, it was found that the concentration of HCl in the EPD suspension significantly influences the neck size to grain size ratio. High neck size to grain size ratio (0.8 ± 0.03) was found in the sintered 0.8 HCl coating. The grain growth was observed to depend on the initial particle packing in the green coating. The effect of chloride ions on the grain and neck growth as well as elemental segregation within the 8YSZ is investigated using photoelectron spectroscopy (XPS) which confirmed the presence of chloride ions in green and sintered 8YSZ coatings. This was later confirmed using high-resolution transmission electron microscopy (HRTEM) and thermal analysis techniques. It was found that the presence of chloride ions induced an increase in the oxygen vacancy concentration at the grain boundaries. High oxygen vacancy concentration in the grain boundaries could promote neck growth of 8YSZ.     

A Highly Regioselective Preparation of 4‐Chloromethyl‐5‐methyl‐2‐aryl‐1,3‐oxazoles

A facile highly regioselective process is described for the formation of 4‐chloromethyl‐1,3‐oxazoles from 1,3‐oxazole N‐oxide/HCl salts. An explanation is presented for the high regioselectivity in deoxygenation‐chlorination using POCl₃ with HCl salts compared to the corresponding free N‐oxides. The method is quite general and the products are isolated by direct precipitation in all cases studied.     

铸造镍钼合金在浓盐酸介质中的钝化膜研究

本文采用多功能电子能谱仪，通过俄歇电子能谱AES和X光电子能谱，对在浓盐酸介质中的铸造镍铬合金的钝化膜进行了分析与研究。结果表明，该合金在50℃、36％HCl介质中，形成了一种含有Cl、Mo为主的氧化物膜。这层薄膜主要是Mo以MoO3形式在表面层富集，Ni在膜中主要以Ni2O3富集在膜的底部，因而提高了膜的稳定性。本试验中采用电化学方法形成的钝化膜厚度大约为10nm，过渡层厚度大约为15nm.     

低浓度和低用量盐酸分解白钨精矿的研究

对低浓度、低用量盐酸分解白钨精矿进行了研究．结果表明：采用分解温度95～105℃，分解时间1．5h，盐酸用量为理论量的1．5倍，浓度为10％的盐酸分解白钨精矿，其平均分解率可达97．35％．与传统酸分解工艺相比，本工艺大量减少了盐酸用量和降低了盐酸浓度，因而显著降低了废酸处理费用和基本上避免了在酸分解过程中HCl气体挥发，这既改善了工作环境条件，又减少了治理HCl气体污染的环保投入费用。其不足之处是酸分解时无除钼作用，且酸液体积较大，为传统工艺酸液体积的1．5倍。     

不同水质及双河注入清水中聚丙烯酰胺水解度的测量

用盐酸滴定、PH计指示终点的方法测量了不同矿化度水质中的HPAM水解度,重点研究了双河注入清水中HPAM水解度的测量,建立了清水量和其消耗的盐酸体积的关系式,校正了碱性离子对水解度测量的干扰。该方法简单准确,不需要对样品进行渗析处理。实验证明．NaCl、CaCl_2对HPAM水解度的测量基本没有影响。     

辉银矿在FeCl3—HCl—NaCl体系中的浸取热力学分析

本文从热力学角度研究了ＦｅＣｌ３－ＨＣｌ－ＮａＣｌ体系从辉银矿（Ａｇ２Ｓ）中浸取银的原理,分析了ｐＨ值、Ｆｅ３＋与Ｃｌ－浓度以及反应温度等浸取热力学条件对反应的影响,并由阿仑尼乌斯公式推导出反应活化能。     

生物质混煤燃烧锅炉过热器受热面金属氯腐蚀特性

在探讨锅炉过热器受热面金属氯腐蚀机理的基础上,模拟生物质混煤燃烧锅炉过热器区域的气相条件及其受热面的积灰情况,采用增重法在水平管式炉上进行了受热面金属氯腐蚀特性试验,研究了不同管材、不同HCl体积分数和不同温度下受热面金属氯腐蚀的特性规律.结果表明:受热面金属氯腐蚀特性曲线均符合抛物线规律,15CrMoG管材的抗腐蚀特性优于12CrMoVG管材;腐蚀速率与HCl体积分数呈线性关系,碱金属氯化物对金属的腐蚀作用大于HCl对金属的腐蚀作用;腐蚀速率与温度呈指数关系,当温度由550℃升高到600℃时,腐蚀速率增幅变大.