无机质复合木材的复合工艺与性能

以我国丰富的速生人工林杨树木材为原料,以含硅、铝、硼、磷元素的离子化合物为浸渍溶液,采用双离子扩散的方法,通过浸渍木材后,使离子在木材孔隙内或细胞壁上发生沉淀反应,所得到的复合材料称为无机质复合木材。由于生成了不溶于水的沉淀物填充在木材的孔隙内,所以改善了木材的热分解特性和强度性能。研究表明,采用负压-正压试验处理设备强制将浸渍溶液灌注入木材内比室温常压浸渍的效果好,增重率能够提高3~5倍;用电子显微镜观察处理木材,无机质物质填充了木材的导管、木纤维和纹孔;热重分析表明,处理材热分解的峰顶点在420℃,到550℃失重率为32 %。在研究范围内,处理材的强度与其增重率呈现正相关关系。     

两步法制备B-Mo共掺杂BiVO4及光催化活性研究

采用柠檬酸络合和浸渍两步法制备了一系列B-xMo共掺杂BiVO_4可见光光催化剂,并采用XRD、XPS、SEM、EDS、BET和UV-vis等表征和分析。以降解甲基橙(MO)、亚甲基蓝(MB)、金橙Ⅱ号(AOⅡ)和罗丹明B(RhB)溶液为指针反应,考察掺杂对BiVO_4可见光催化活性的影响。结果表明:B-Mo共掺杂能抑制BiVO_4晶粒生长,比表面积增大,共掺杂后BiVO_4禁带宽度窄化,且氧空位较单掺杂增加。当Mo掺杂量为2.5%(原子分数)时制备的B-2.5Mo-BiVO_4对甲基橙的降解率达96%左右,且该样品也能有效降解亚甲基蓝(MB)、金橙Ⅱ号(AOⅡ)和罗丹明B(RhB)溶液。     

干法浸渍过程模型的激波理论解及实验研究

本文探讨了干法浸渍过程中达到吸附平衡时，催化剂前体在球形截体内的浓度分布。对单组分浸渍于渗透－吸附模型提出了具有一般意义的边界条件，应用激波理论得到了浓度分布的解析解。实验测定了硝酸铜溶液－硅胶体系和模型参数及φ5毫米载体内的浓度分布。理论计算与实际分布基本吻合。     

Quality and antioxidant capacity of fresh‐cut apple wedges enriched with honey by vacuum impregnation

The effect of vacuum impregnation (VI) of fresh‐cut apple wedges with honey, in presence and absence of a browning inhibitor on physicochemical, sensory and antioxidant properties over 7 days of storage at 2–4 °C was studied. Infusion of wedges with honey resulted in very little weight change indicating loss of internal water and ingress of honey carbohydrates into the wedges, hence the correlation coefficients with soluble solids content (r = ?0.91) and dry matter (r = ?0.77). Water infused samples showed the highest water uptake resulting in an increase in weight of 30%. Browning (P < 0.001) and firmness (P < 0.001) of apple wedges were the quality parameters most affected by VI. Samples dipped in browning inhibitor prior AS1 showed slightly better performance than undipped wedges with regard to browning and firmness. Total phenol content and antioxidant activity were significantly (P < 0.001) lower for honey infused apple wedges.     

Kinetics of adsorption of sulfur mustard on Al2O3 nanoparticles with and without impregnants

BACKGROUND: Chemical warfare (CW) agents are highly toxic compounds and have been used in war to produce physical immobilization, so safe and effective ways to detoxify them without endangering human life or the environment is of great concern. One of the important ways to achieve protection against CW agents contaminating air is to utilize suitable adsorbent materials, e.g. activated carbon, nanoparticles, etc. In the present study nanoparticles, synthesized through sol–gel processes and loaded with reactive compounds have been used for the degradation of CW agents and to understand their adsorption kinetics using Fickian and linear driving force models. RESULTS: Nanoparticles of AP‐Al₂O₃ (aerogel‐produced alumina) in the size range 2–30 nm with high surface area (375 m² g^?1) were produced by an alkoxide‐based synthesis, and then characterized using N₂‐Brunauer–Emmet–Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD) and thermogravimetric analysis (TGA) techniques. Thereafter, these were impregnated, and finally tested for kinetics of adsorption of sulfur mustard (HD) under static conditions. The kinetics was studied using linear driving force and Fickian diffusion models and the kinetics parameters determined. CONCLUSION: AP‐Al₂O₃ with 10% impregnation of 9‐molybdo‐3‐vanadophosphoric acid (10%, w/w) showed the maximum uptake (640 mg g^?1) of HD. The highest adsorption potential indicated that the adsorption was due not only to physisorption but also involved chemisorption. Values of the diffusional exponent indicated the mechanism to be Fickian and anomalous. Hydrolysis, dehydrochlorination and oxidation reactions (identified using gas chromatography‐mass spectrometry (GC/MS)) were found to be the route of degradation of HD over the prepared nanoparticle based adsorbents. Copyright © 2009 Society of Chemical Industry     

用中温沥青研制电极浸渍沥青

以中温沥青为原料，选择价廉易得的有机溶剂，采用较简便的净化工艺，可制得符合炭素厂要求的电极浸渍沥青，为中间试验提供了相关的工艺参数。     

我国耐火材料真空油浸技术的现状与未来

对我国耐火材料行业的真空浸渍工艺及设备现状进行了分析，介绍了国产化真空油浸装备及工艺特点。指出今后应积极倡导推广应用高温、高压，符合环保要求的真空油浸工艺及装备。     

硅酸钠/聚乙二醇浸渍改性杨木工艺及性能研究

目的 为了提高速生杨木的物理力学性能、尺寸稳定性、热稳定性等性能，以硅酸钠(Na2SiO3)溶液和聚乙二醇(PEG)溶液为改性剂，旨在提高杨木的力学性能、尺寸稳定性以及耐热性能，并探究硅酸钠质量分数、聚乙二醇质量分数以及分子量对改性杨木性能的影响，获得最佳浸渍工艺。方法 运用单因素试验法探究硅酸钠质量分数、聚乙二醇质量分数、聚乙二醇分子量3个因素对改性杨木浸渍效果的影响。通过最佳浸渍工艺制备硅酸钠/聚乙二醇改性杨木与硅酸钠改性杨木，并测定其顺纹抗压强度、表面硬度、吸湿体积膨胀率等性能和结构表征，探究其与未改性杨木的差异。结果 通过单因素试验结果可知，以质量分数为10%的Na2SiO3、PEG-400以及质量分数为5%的PEG-400的浸渍工艺制备出改性杨木性能较佳。硅酸钠/聚乙二醇杨木改性材的顺纹抗压强度、抗弯强度、端面硬度、径面硬度和弦面硬度较未改性杨木的分别提高了69.4%、19.1%、42.2%、39.5%、19.2%，吸湿体积膨胀率较硅酸钠改性材降低了40.0%。结论 速生杨木经过硅酸钠/聚乙二醇改性后的力学强度，相较于单独硅酸钠改性杨木的力学强度有所提升，尺寸稳定性能增强，因此在性能及应用方面，硅酸钠/聚乙二醇改性杨木更具优势。     

Synthesis of pure zeolite Y using soluble silicate, a two-level factorial experimental design

Four methods were used for the synthesis of pure zeolite Y using soluble silicate as a silica source: (1) the gelling of soluble silicate to silica–alumina gel, by aluminate (or aluminium sulphate), (2) the precipitation of soluble silicate to precipitated silica–alumina gel, by aluminate (or aluminium sulphate), (3) the gelling of soluble silicate by sulphuric acid plus alumina impregnation, and (4) the precipitation of soluble silicate by sulphuric acid plus alumina impregnation. A 2⁴ two-level factorial design was used to study the influence of four different variables on the purity of zeolite Y (expressed in terms of degree of crystallinity). The ageing time turned out to be the most significant variable. Synthesis time, alkalinity and mixing rate were also found to be statistically significant. X-ray diffraction patterns were used to characterize the samples, which ranged from well-crystallized faujasite structures to amorphous materials. The highest purity achieved in method (1) was 38%. The best synthesis condition derived from method (1) was applied to the other three methods. Only method (4) yielded the pure zeolite Y. Therefore, the effect of silica–alumina precursor preparation on producing the pure zeolite Y is extremely important.     

五金紧固件锌铝复合涂层及其防腐蚀性能

针对湛江海洋环境冶金设施紧固件防腐蚀需要,设计并研究了粉末渗锌和锌铝膜复合涂层防腐蚀体系。采用浸涂烘干焙烧方法制备锌铝膜涂层,利用电化学方法测试粉末渗锌和锌铝膜复合涂层的性能。结果表明,采用主要成分为鳞片锌粉285g/L、鳞片铝粉65g/L和钼酸钠30g/L等组成的涂液体系进行浸涂并经70~80℃干燥及300℃焙烧可制备性能较好的锌铝膜,锌铝膜和渗锌层与钢基体相比同属于阳极,其自腐蚀电位和自腐蚀电流密度明显低于40Cr钢基体;3.5%NaCl中锌铝膜在约-0.80V~-0.30V(Ag/AgCl)电位区间存在钝化现象。