Effect of carbon-containing additions on periclase-carbon refractory properties

Results are provided for a study of the effect of pitch additions of a different nature on binder properties and refractory material quality in the production of periclase-carbon refractories. The desirability is established of using coal-tar and petroleum pitches as a carbonizing agent for refractory material.     

Surface-active properties of hydrophobized derivatives of lignosulfonates: Effect of structure of organosilicon modifier

An investigation of regularities of surface-tension alterations in the aqueous solutions of lignosulfonate and aluminum-containing organosilicon oligomer (olygoheterosiloxanolates) reaction mixtures revealed that modification with oligomers can be used for the regulation of the surface activity of lignosulfonates. High surface activity not only in acidic, but also in neutral and alkali media, is achieved using oligomers which consist of ethylsesquioxane and diethylsiloxane links. In this case, increasing hydrophobicity compensates the negative effects (increase of solubility and the Coulomb repulsion) of ionization of lignosulfonate acidic groups. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1013–1020, 2001     

Effect of additions of oligomeric epoxides on the physicochemical properties of cellulose acetates

Conclusions The effect of oligomeric epoxides based on polyethylene oxide and epichlorohydrin, having an epoxy group content of 8–15%, on the physicochemical and structural—mechanical properties of solutions and films of CA has been described.It has been shown that, in the first stages of degradation, the modifiers are effective thermostabilizers (at a content from 0.5 to 10% of the weight of the CA).The devitrification region of the modified specimens is shifted in the low-temperature direction by 5–33°C on increase of the oligomer content from 2 to 15%; the relative elongation rises by a factor of 1.2 to 3.Under the influence of the modifiers, the viscosity and turbidity of concentrated CA solutions are reduced; the specific bulk electrical resistance of films containing modifiers is reduced by several orders of magnitude.Translated from Khimicheskie Volokna, No. 3, pp. 45–46, May–June, 1984.     

Effect of calcined colemanite additions on properties of hard porcelain body

Utilization of calcined colemanite as a sintering aid in hard porcelain body, prepared by slip casting route using aqueous suspension containing mixtures of kaolin, quartz and potassium feldspar, was investigated. After calcination, colemanite powders were added to the admixture of porcelain by partial substitution with potassium feldspars in the range of 0–5 wt% to discover its influences on the densification and technological properties of the final product. Through optimization of process parameters of ceramic suspensions by using appropriate dispersing agents and facilitating densification by calcined colemanite addition, hard porcelain possess high strength was obtained. When relationship between the additive concentration with temperature was established, it is found that porcelain formulations resulted in substantial reduction of firing temperature about 50 °C without compromising its quality by 1 wt% calcined colemanite addition.     

Effect of surface modifying macromolecules on the properties of poly(vinylidene fluoride) membranes

Poly(vinylidene fluoride) (PVDF) membranes were surface-modified using fluorotelemer intermediate Zonyl BA-L as a fluorinated surface modifying macromolecules (SMM) additives in the concentration range from 0 to 2 wt.%. Prepared membranes were characterized by contact angle measurement, electron spectroscopy for chemical analysis (ESCA), scanning electron microscopy (SEM), and pervaporation test. The experimental results showed that SMM migrated to the surface and effectively increased the surface hydrophobicity of the PVDF membranes. The pure water permeation flux evaluated by pervaporation decreased with an increase in the content of SMM.     

Effect of glass-ceramics and sillimanite sand additions on microstructure and properties of porcelain

Both quartz and feldspar were progressively replaced by ground sillimanite sand and glass-ceramics in a classical porcelain composition and the effect of these replacements on the vitrification behaviour and mechanical and thermal properties in relation to the microstructure of specimens has been investigated. Progressive additions of sillimanite sand and crystallising glasses leading to the complete replacement of quartz and feldspar increased the strength, toughness and modulus significantly, and drastically reduced the per cent thermal expansion in the composition. The improvement in the properties is attributed to dramatic changes in the microstructural features as a result of significant reduction in the content of glassy phase and the simultaneous increase in crystalline phases such as mullite, sillimanite and cordierite.     

Effect of the additions of the waste products of rare-earth elements on the properties of mullite-zircon suspensions

Conclusions The effect of the REE compounds on the rheological properties of the mullite-zircon suspensions was studied. The optimum interval of casting was established. The effect of the REE compounds on the sintering process of the mullite-zircon systems was studied. We demonstrated the possibility of decreasing their sintering temperature by 100°C (up to 1450°C) without loss of thermal shock resistance of the products.Translated from Ogneupory, No. 2, pp. 10–13, February, 1987.     

氧化剂对无铬木质素磺酸盐类钻井液处理剂作用效能的影响

为了提高无铬木质素磺酸盐在钻井液中的作用效能，用生产橡碗 栲胶的废渣为原料制备的无铬木质素磺酸盐，与氧化剂（Ｈ_２Ｏ_２、ＭｎＯ_２、 ＫＭｎＯ_４、ＨＮＯ_３、ＣａＣｌ_２Ｏ_７）进行反应，并测定氧化产物在钻井液中的作用 效能．结果表明，用 ＫＭｎＯ_4、ＨＮＯ_3和 ＣａＣl_2Ｏ_7作氧化剂时，其氧化产物 所处理的钻井液性能恶化；用Ｈ_2Ｏ_２和 ＭｎＯ_２作氧化剂时，其氧化产物所 处理的钻井液性能变好。     

复合抗氧化剂加入量对Al2O3-SiC-C浇注料性能的影响

以电熔棕刚玉为骨料,电熔棕刚玉粉、活性α-Al2O3微粉、黑碳化硅粉、球状沥青、SiO2微粉、纯铝酸钙水泥等为基质料,配以质量分数为2%、2.3%、2.6%、2.9%的复合抗氧化剂,搅拌均匀制备成Al2O3-SiC-C质浇注料。外加5%(w)的水搅拌3~5 min后,检测浇注料的流动性;经振动成型、养护、脱模、干燥后,于1 500℃空气气氛中热处理3 h,测定热处理后试样的质量损失率、体积密度、显气孔率、常温耐压强度、常温抗折强度和抗热震性。结果表明:随着复合抗氧化剂加入量(w)从2%增加到2.9%,浇注料的流动性变化不大并且保持较高的水平,显气孔率、体积密度和常温强度变化不大,质量损失率从1.14%减小到0.35%,氧化层厚度逐渐减小;复合抗氧化剂加入量为2.9%(w)的试样热震后耐压强度仍保持在70 MPa左右,具有较好的抗热震性。     

Effect of alumina and titania additions on properties of porcelain bodies from murakami sericite

The effect of alumina and titania additions on the properties of porcelain bodies fabricated from Murakami sericite by firing at 1100–1300°C was investigated. Additional alumina might have the dispersion strengthening effect so that the strength increased to 180 MPa, which was observed for the body fabricated by adding 30 wt% alumina and firing at 1200°C, approximately 50% higher than one with no addition. Furthermore, titania additions of 5 wt% caused the strength to improve markedly to 240 MPa by promoting formation of acicular mullite which may have a fiber-reinforcing effect. The Vickers micro hardness was also improved from 4·9 GPa to 7·3 GPa. The resistivity was 10¹²Ω.m, sufficient for an electric insulator.     

Rheological properties of water-coal slurries based on brown coal in the presence of sodium lignosulfonates and alkali

The effect of the oxidized surface of brown coal on the structural and rheological properties of water-coal slurries was found. The kinetics of structure formation processes in water-coal slurries based on as-received and oxidized brown coal was studied. The effect of lignosulfonate and alkali additives on the samples of brown coal was considered.