水泥窑用耐碱浇注料的性能研究

本研究中以建筑陶瓷为主要原料制备耐碱浇注料,重点研究了铝酸钙水泥和硅微粉对耐碱浇注料性能的影响,并对试样的显微结构进行了分析。试验结果表明:铝酸钙水泥加入量的增加有助于110℃,24 h处理后常温强度的提高,而在10100℃,3 h处理条件下,铝酸钙水泥加入量的增加会提高基质中生成的液相,加入量在一定范围内使强度出现先增加后降低的趋势,同时也导致了线变化率的增加,在试验条件下铝酸钙水泥的合适加入量在7%~8%左右;耐碱浇注料中加入活性较高的硅微粉能够提高试样的强度和致密度,其加入量增加也会导致试样线变化率的增加,综合分析硅微粉的加入量以5%~6%为宜;经1100℃,3h处理后的试样中骨料和基质结合牢固,基质中存在莫来石化和低共熔物生成的双重反应。     

耐火耐碱浇注料在大型预热器窑上的应用

耐火耐碱浇注料在大型预热器窑上的应用刘大正河北省冀东水泥厂（０３６０３０）河北省冀东水泥厂为日本石川岛公司全套引进的具有８０年代初期国际先进水平的大型预分解窑，日产熟料４０００ｔ。建厂时，全套烧成系统设备所需的耐火衬料均由日方配套引进。其特点是在设备...     

水泥窑用低水泥浇注料性能的研究

以矾土为主要原料,铝酸钙水泥和硅微粉为结合系统,研究了不同热处理温度对水泥窑用低水泥浇注料性能的影响。试样自然干燥24h脱模后,再经110℃烘干24h,分别于300℃、500℃、700℃、900℃、1100℃、1300℃和1500℃热处理3h。检测各温度热处理后试样的体积密度(B.D)、线变化率(P.L.C)、常温抗折强度(M.O.R)、常温耐压强度(C.C.S)、常温耐磨性能以及试样的热膨胀系数和抗热震性能。结果表明,随着热处理温度的提高,水泥窑用低水泥浇注料的体积密度呈现先减小后不变再增大的变化规律;线变化率呈现收缩先增大后减小再增大的变化规律;常温抗折强度和常温耐压强度呈现先增大后减小再增大的变化规律。水泥窑用低水泥浇注料经过1500℃热处理后的磨损量小于经过1300℃热处理后的磨损量。水泥窑用低水泥浇注料具有相对优良的抗热震性能。     

水泥窑用耐磨耐火浇注料的研究

<正>近年来,我国水泥工业发展迅猛,耐磨浇注料作为水泥窑用的内衬材料得到充分的重视,新型干法水泥窑耐火材料使用部位较多,不同规格的水泥窑及系统的不同使用部位,对耐火材料都有不同的     

硅溶胶对刚玉浇注料性能的影响

以5～8、3～5、1～3及≤1 mm的电熔刚玉为骨料,致密刚玉粉(≤0.074 mm)、白刚玉粉(≤0.043mm)及α-Al2O3微粉为细粉,矾土水泥和硅溶胶为结合剂,按骨料、粉料质量比为64∶36配料制成试样,自然养护后于110℃24 h烘干,然后分别于815℃3 h、1 100℃3 h和1 400℃3 h热处理。对处理后试样进行了常温抗折强度、耐压强度、体积密度、线变化率和抗热震性能的检测及显微结构分析。结果表明:硅溶胶结合浇注料于1 100℃3 h处理后的抗折强度和耐压强度分别达到27.1和178 MPa,远高于相同温度下水泥结合浇注料的;硅溶胶结合浇注料在20～1 100℃水冷热震循坏100次后基本没有出现裂纹,其耐压强度损失率仅为24.4%,而水泥结合的浇注料热震循坏49次后就完全开裂。     

中间包用浇注料的高温性状

中间包用浇注料的主要材质为Ａｌ２Ｏ３－ＳｉＯ２系，其损毁原因主要有三个方面，其它二个方面已基本解决，而龟裂和剥落尚有许多问题没有解决 本文针对该问题，研究了耐渣渗透性和耐热震稳定性的评价方法。     

组合式模板在窑口浇注料施工中的应用

众所周知,新型干法回转窑窑口均采用浇注料内村。浇注料施工时需采用模板定型。传统的木制模板虽然具有制作方便、透气性好、有利于浇注料养护等优点,但亦存在施工中容易损坏,重复使用性差,成本高等缺点。有的厂家全部采用铁皮做模板,支一段壳子板,浇一段饶注料,这种施工方法不仅难度大,且成本更高（铁皮只能使用一次）,更加不可取。因此对传统模板必须进行改进。针对传统模板的特点,我们对其做了改进。由于改进后的模板既有木板又有铁板,加之其组合非常方便,故称之谓组合式模板。具体改进方法为：（l）为方便施工,用3mm厚的钢…     

中间包浇注料的损杂机理

为提高中间包浇注料的寿命,开发了抑制浇 注料发生龟裂和剥落的材质。评价使用表明,降低浇 注料的Ａｌ２Ｏ３／ＳｉＯ２比,增加超细铝粉的添加量,能强化浇注料的组织提高热震性,有效的地防止涂覆材料的烧结。     

CF/SiC增强摩阻材料性能研究

采用模压法制备了碳纤维(CF)/碳化硅(SiC)增强摩阻材料,通过摩擦试验研究了CF和SiC质量分数及CF长度对材料摩擦磨损特性的影响。结果表明:随着SiC质量分数的增加,摩擦系数和磨损率都有明显提高,这是由于硬质颗粒的犁沟作用;当CF质量分数<10%时,CF质量分数和长度对摩擦磨损性能影响明显,这归因于CF本身具有良好的自润滑性能以及抗犁削作用。     

The concept of materials brittleness and its applications

Brittleness is a significant property considered in product design and the research and development of materials. However, for a long time the methods to determine brittleness have been largely “hand-waving” arguments or else circumferential properties—in other words describing numerous properties related to brittleness but not actually quantifying brittleness itself. We have defined brittleness of polymeric materials quantitatively with applications to multiple areas. Relationships between brittleness and both tribology and mechanics have been discovered and are described. Moreover, the definition has been applied in the development of multilayer composite materials; structural integrity of the composites decreases with increasing brittleness. Other applications and the fact that toughness is not an inverse of brittleness are also discussed.     

杭锦2#土复合材料的制备及对磷酸根吸附性能

以寻求廉价而高效的吸附材料为目的,研究了利用聚合硫酸铝改性杭锦2#土制备复合吸附剂的方法.用此吸附剂对生活废水中的磷酸根进行吸附,讨论了磷酸根浓度、溶液pH值、温度对吸附容量的影响.结果表明:增加初始磷浓度,去除率下降,吸附量和吸附平衡时间增加;溶液pH值为6-10时复合吸附剂对磷酸根的去除效果最好;吸附能力随温度的升...     

C60-containing nanostructured polymeric materials with potential biomedical applications

Star-shaped polymers with a fullerene (C₆₀) core and an unexpanded structure were successfully prepared by reaction of C₆₀ with amino end-capped polyesters H_xC₆₀(NHPCL_n)_x and polyethers H_xC₆₀(NHPEG_n)_x, respectively. Upon irradiation of these C₆₀-derivatives, a large amount of singlet oxygen was released. Compared to previously synthesized star-shaped azafulleroids with an expanded structure, the photosensitivity of H_xC₆₀(NHPCL_n)_x is higher as assessed by a higher production of singlet oxygen. The cytotoxicity of the photoactive water-soluble H_xC₆₀(NHPEG_n)_x derivatives was tested against THP-1 cells and expressed in terms of cell viability. Moreover, they were processed as micro-/nanosized fibers by electrospinning, which however required the addition of poly(?-caprolactone) (PCL). The diameter distribution of the fibers was trimodal, where the fraction with the 270 nm average diameter was the major population. Because of their photoactivity, the herein reported star-shaped C₆₀-derivatives are promising candidates for photodynamic cancer therapy and treatment of multidrug resistant pathogens.     

Properties and applications of some structural refractory ceramic materials based on nonmetal nitrides

New composite ceramic materials developed at the Central Materials Research Institute, including nitride-oxide composites based on hexagonal boron nitride and nitride composites based on silicon nitride are described. Some important technological aspects of the production of articles and parts from these materials are considered. Data on the properties and main applications of the composites are reported. Translated from Ogneupory i Tekhnicheskaya Keramika, No. 3, pp. 34–35, March, 1997.     

碳化硅质结构陶瓷材料的制造、性能和使用范围

阐述由碳化硅制造陶瓷材料的主要方法及其工艺特点，还介绍了该材料的性能和使用范围。     

Fabrication and Properties of Ti3SiC2/SiC Composites

Ti3SiC2/SiC composites were fabricated by reactive hot pressing method. Effects of hot pressing temperature, the content and particle size of SiC on phase composition, densification, mechanical properties and behavior of stress-strain of the composites were investigated. The results showed that ： （ 1 ） Hot-pressing temperature influenced the phase composition of Ti3SiC2/SiC composites. The flexural strength and fracture toughness of composites increased with hot pressing temperature. （2） It became more difficult for the composites to densify when the content of SiC in composites increased. It need be sintered at higher temperature to get denser composite. The flexural strength and fracture toughness of composites increased when the content of SiC added in composites increased. However, when the content of SiC reached 50 wt%, the flexural strength and fracture toughness of composites decreased due to high content of pore in composites. （3） When the content of SiC was same, Ti3SiC2/SiC composites were denser while the particle size of SiC added in composites is 12. 8 μm compared with the composites that the particle size of SiC added is 3 μm. The flexural strength and fracture toughness of composites increased with the increase of particle size of SiC added in composites. （4） Ti3SiC2/SiC composites were non-brittle fracture at room temperature.     

二维金属有机框架的制备及其在生物传感器领域的研究进展

介绍了二维金属有机框架的物理性质、化学性质、合成方法和应用新进展,对合成方法优缺点进行了对比分析,以及在合成过程中常出现的问题进行讨论和分析。综述了二维金属有机框架的国内外研究进展,重点阐述了二维金属有机框架在DNA检测、H_2O_2检测、金属离子检测、生物分子检测方面的研究。展望了其广阔的发展和应用前景,对以后的研究重点和发展方向进行了讨论。     

Gel casting of mullite for radome applications

Gel-casting method was used to fabricate mullite ceramics because this method has not been applied to fabricate dense mullite in literature. Gel-casting parameters such as monomer types (acrylamide and metyhlenebisacrylamide), effect of initiator (ammonium persulfate), and catalyst (tetramethylenediamine) were studied. All samples reached to relative densities of 97% to 98.2% after sintering at 1540°C for 2 hours. Backscattered SEM images revealed anisotropically grown mullite grains, glassy phase located at triple junctions, hexagonally-shaped and faceted Al₂O₃ grains, and white-color grains consisting of ZrO₂ and undissolved TiO₂. A Weibull modulus of 12.33 (ie, indicating tough ceramics) and characteristic strength of 186 MPa were calculated, below which no failure was expected. A critical quenching temperature was found as about 400°C (ΔT ~ 380°C) by indentation-quench method. In addition, a thermal shock resistance parameter (eg, R in °C) of 142.4°C was calculated, which was higher than commonly used Al₂O₃ ceramics. Lower dielectric constant and loss are desired for wide frequency band application and shorter signal transmission delay time in radomes. The dielectric constant was found as nearly 7.5 up to 10 GHz and loss tangent was 0.0031 at 5 MHz. Dielectric and thermomechanical results suggest that mullite is a suitable candidate ceramic for radome applications.