金属氧化物催化氧化氯化氢制氯气的研究

氯化氧HCl气体催化氧化制备氯气Cl2对氯元素的高效循环利用具有重要意义.采用程序升温分析技术(TPAT)研究了14种金属氧化物(AlO3、TiO2、Cr2O3、Fe2O3、ZnO、CoO、CuO、La2O3、CaO、MgO、RuO2、MnO2、CeO2、Co3O4)吸附HCl与释放Cl2的效果,通过X射线衍射仪(XRD)探讨了金属氧化物与HCl反应的过程机理,使用X射线光电子能谱仪(XPS)检测了反应后样品残氯量,利用Gaussian 03程序计算了热力学数据.结果表明,CoO具有较好的吸附HCl的效果,吸附率85.4%;所得氯化物还可高效氧化牛成Cl2,释放率85.2%,残氯量12.8%,多次循环使用效果仍较好,是两步法(Benson过程)催化氧化HCl制备Cl2的最优催化剂;在研究温度范围内,氯化阶段为放热自发不可逆过程,氧化阶段与此相反.     

模糊算法在氯丁二烯合成生产中的应用

氯丁橡胶生产是以氯丁二烯单体经过乳液聚合生产胶乳,而氯丁二烯则是以乙炔法制备。乙炔二聚得到的乙烯基乙炔(MVA)与氯化氢(HCl)合成生成氯丁二烯(CD),国内其合成塔反应运行基于人工操作,劳动强度大且稳定性差。在自动控制方面,设计了三维模糊(Fuzzy)控制器,与传统的PID串级控制相结合,实现了合成反应塔的优化控制。     

Synthesis and characterization of new cardo poly(bisbenzothiazole)s from 1,1‐bis(4‐amino‐3‐mercaptophenyl)‐4‐tert‐butylcyclohexane dihydrochloride

A new monomer 1,1‐bis(4‐amino‐3‐mercaptophenyl)‐4‐tert‐butylcyclohexane dihydrochloride, bearing the bulky pendant 4‐tert‐butylcyclohexylidene group, was synthesized from 4‐tert‐butylcyclohexanone in three steps. Its chemical structure was characterized by ¹H NMR, ¹³C NMR, MS, FTIR, and EA. Aromatic poly(bisbenzothiazole)s (PBTs V) were prepared from the new monomer and five aromatic dicarboxylic acids by direct polycondensation. The inherent viscosities were in the range of 0.63–2.17 dL/g. These polymers exhibited good solubility and thermal stability. Most of the prepared PBTs V were soluble in various polar solvents. Thermogravimetric analysis showed the decomposition temperatures at 10% weight loss that were in the range of 495–534°C in nitrogen. All the PBTs V, characterized by X‐ray diffraction, were amorphous. The UV absorption spectra of PBTs V showed a range of λ_max from 334 to 394 nm. All the PBTs V prepared had evident fluorescence emission peaks, ranging from 423 to 475 nm with different intensity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2000–2008, 2006     

石灰在旋风收尘器内对HCl气体的中高温净化

实验研究了带直管的旋风收尘器内石灰在450～770℃的中高温对HCl气体的净化效果.研究发现:消石灰自身煅烧反应对吸收效率有较大影响,石灰干式净化效率在650～670℃显示出峰值.烟气中的CO2促使石灰碳酸钙化,削弱了对HCl气体的吸收效果;但改性石灰与普通石灰相比,CO2分压的改变对效率影响较小.随着HCl气体质量浓度和烟气中钙氯当量比的提高,HCI的净化效率提高;但烟气中钙氯比超过4～6以后净化效率不再明显上升.采用带直管的旋风收尘器在合适温度下对HCI气体的净化效率在40%～50%.     

酸洗缓蚀剂的应用研究

酸洗缓蚀剂可对带钢表面产生较好的防护作用,从而减少酸对带钢的腐蚀。研究了缓蚀剂的作用机理,对添加、未添加及添加不同量缓蚀剂酸洗后带钢的表面质量、成材率,以及对停机带钢的作用效果进行了试验对比。结果表明:添加缓蚀剂未影响氧化铁皮的酸洗效率,但可以明显降低盐酸对带钢的腐蚀程度,有效降低铁损、抑制过酸洗的发生,使酸洗后带钢表面白亮,可提高成材率0.162%,降低吨钢换酸量13.8%,同时有利于停机卷的轧制,改善车间环境,减少污染。     

连续蒸馏浓缩高酸稀土反萃液工艺及设备研究

对连续蒸馏浓缩高酸稀土反萃液工艺及设备进行了研究，结果表明：研制的以石英为材质、电热管内加热孔式微循环双效连续蒸发器（已获专利），可以在连续蒸馏浓缩稀土反萃取的同时回收盐酸。从而解决了稀土分组、分离生产中高酸稀土反萃液工艺的衔接等问题，提高了收率，降低了成本，而且没有环境污染。     

Occurrence and molecular identification of anisakid nematodes isolated from Pacific cod (Gadus macrocephalus) caught off Korea

Anisakids nematodes from Pacific cod (Gadus macrocephalus) in Korea were investigated and their molecular identification was conducted, to assess the epidemiological role of Pacific cod in human anisakidosis in Korea. Totally 238 Pacific cod were caught from 5 different areas around Korean peninsula. Fish were dissected and carefully examined for collecting nematodes. PCR-RFLP and the subsequent sequencing were conducted for molecular identification of those nematodes. A high prevalence of infection (193/238, 81.1%) in Pacific cod was observed, and 1694 nematodes were collected. 79.1% (1340/1694) of the nematodes were found freely in the body cavity of Pacific cod, and the rest of them (20.9%, 354/1694) were in the digestive tract or attached to other organs. PCR-RFLP analysis using HinfI and RsaI restriction enzymes revealed 3 different banding patterns corresponding to Anisakis pegreffii, Hysterothylacium aduncum and hybrid genotype (Anisakis simplex × A. pegreffii), respectively. Of 1694 nematodes, 1280 (75.6%) were identified as A. pegreffii and 406 (24.0%) were H. aduncum. A. pegreffii occupied 84.0% (1125/1340) of the nematodes in the body cavity and 40.0% (132/330) of them in the digestive tract, but no nematodes were found in Pacific cod muscles.     

Solid State Interaction of Raloxifene HCl with Different Hydrophilic Carriers During Co-grinding and its Effect on Dissolution Rate

This study investigated the effects of different classes of hydrophilic carriers (poly vinyl pyrrolidones [PVPs] [Plasdone K-25 and Plasdone S-630], cellulosic polymers [hydroxypropyl methyl cellulose and hydroxy propyl cellulose], and Sodium Alginate) on the solid state and dissolution rate of Raloxifene hydrochloride (R-HCl). Solid state characterizations of co-ground mixtures and physical mixtures in 1:1 and 1:2 ratios of drug to polymer were performed by employing laser diffractometer for particle size and differential scanning calorimetry (DSC) for solid state interactions. The results of particle size studies showed that only co-grinding with PVPs was more effective in the reduction of particle size than the milling of drug alone. DSC study indicated that the crystalline nature of the drug was reduced after co-grinding with PVPs when compared with their corresponding physical mixtures. The hydrophilic carriers other than PVPs did not reduce the crystalline nature of the drug significantly. X-ray diffraction and scanning electron microscopy were carried out for selected batches to confirm DSC results. Significant enhancement in dissolution rate and extent was observed with co-ground mixtures of drug and PVPs. Plasdone S-630 was found to be a better carrier for R-HCl in terms of achieving improvement in dissolution. In vitro dissolution data can be described by Hixson–Crowell model, indicating the drug release mechanism predominated by erosion.     

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.     

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.