采用防爆剂克服搪瓷鱼鳞爆

国内外的许多学者对鱼鳞爆的形成机理已经进行过大量的研究。早期的一些研究者由于缺乏设备来准确检查、分析鱼鳞爆产生过程中释放出的气体,因此未能将鱼鳞爆归结于钢板中的氢,而认为鱼鳞爆是由于钢板与瓷层之间结合不牢固所造成的。现在,随着科学技术的不断发展,人们发现鱼鳞爆形成的最主要原因是钢板中氢的吸收、扩散和溢出所致。 Moore和Sweo通过研究证实,瓷釉中结合的水和炉窑中空气的水份占氢源总量的     

漆包线弯曲盐水针孔试验法的标准化探讨

本文通过介绍了用漆包线弯曲盐水针孔试验法检验漆包线的漆膜连续性、附着性的理论基础及其应用前景。     

Membrane Targeting and GTPase Activity of Rab7 Are Required for Its Ubiquitination by RNF167

Rab7 is a GTPase that controls late endosome and lysosome trafficking. Recent studies have demonstrated that Rab7 is ubiquitinated, a post-translational modification mediated by an enzymatic cascade. To date, only one ubiquitin E3 ligase and one deubiquitinase have been identified in regulating Rab7 ubiquitination. Here, we report that RNF167, a transmembrane endolysosomal ubiquitin ligase, can ubiquitinate Rab7. Using immunoprecipitation and in vitro ubiquitination assays, we demonstrate that Rab7 is a direct substrate of RNF167. Subcellular fractionation indicates that RNF167 activity maintains Rab7′s membrane localization. Epifluorescence microscopy in HeLa cells shows that Rab7-positive vesicles are larger under conditions enabling Rab7 ubiquitination by RNF167. Characterization of its ubiquitination reveals that Rab7 must be in its GTP-bound active form for membrane anchoring and, thus, accessible for RNF167-mediated ubiquitin attachment. Cellular distribution analyses of lysosome marker Lamp1 show that vesicle positioning is independent of Rab7 and RNF167 expression and that Rab7 endosomal localization is not affected by RNF167 knockdown. However, both Rab7 and RNF167 depletion affect each other’s lysosomal localization. Finally, this study demonstrates that the RNF167-mediated ubiquitination of Rab7 GTPase is impaired by variants of Charcot–Marie–Tooth Type 2B disease. This study identified RNF167 as a new ubiquitin ligase for Rab7 while expanding our knowledge of the mechanisms underlying the ubiquitination of Rab7.     

耐硫酸露点腐蚀的导热搪瓷技术

文章主要介绍了导热搪瓷这种新技术的特点,炼油厂及电厂的加热炉和空气预热器的硫酸露点腐蚀状况,以及导热搪瓷在电厂和炼油厂使用情况。河北郁宏搪瓷有限公司采用静电(干法)搪瓷技术生产的回转式和管箱式导热搪瓷空气预热器已在许多电厂和化工企业得到应用,使用寿命一般超过8年。中国石油天然气股份有限公司锦州分公司将三组搪瓷空气预热器于2004年10月应用于催化裂化重整装置,使加热炉的排烟温度从投用前的282℃降至投用后的136℃,同时使加热炉每月的燃气消耗减少60t。     

Tooth flank modification theory of dual-torus double-enveloping hourglass worm drives

In this paper, the theory of tooth flank modification is enriched and developed for a double-enveloping toroidal worm drive. The goal and significance of the modification are expounded from the point of view of changing the tooth flank configuration for the worm gear pair. It is pointed out that the constant center distance modification, the constant transmission ratio modification, and the combination of the previous two are the convenient and reasonable modification strategies. All the corrected hourglass worm pairs, attained by employing the preceding modification methodology, can be divided into two fundamental types: the type I worm pair and the type II worm pair, from the perspective of the meshing behavior. The division criterion of the worm drive type is moreover provided on the basis of the value range of the modification parameters in this study. The meshing characteristics of the two types of the modified globoidal worm drive are summarized in detail. The results indicate that the type II worm gearing with slight modification should be the preferred style for the double-enveloping toroidal worm drive.     

牙齿松动位移测量仪的研究

本文针对牙齿松动位移测量仪的研制,就其位移传感原理,信号处理以及相关的机械结构进行了理论分析,整机实验结果与临床试用表明,本测量仪的性能指标达到了临床应用的标准。     

提高臭氧发生器放电室效率的研究

本文根据管式臭氧发生器放电室的电晕放电功率方程式,分析了臭氧发生器的发展趋势,设计了搪瓷介电体的臭氧发生室。对玻璃和搪瓷材料进行了电性能参数测试。对玻璃和搪瓷民体的臭氧发生器产率和电耗参数进行了测量比较。结果表明：Ｘ 搪瓷介电体臭氧发生器比玻璃介电体臭氧发生器臭氧产率提高了４４％,电耗降低了４２％。     

Influence of priming time and primer’s concentrations on bovine enamel bond strengths

This study investigated the effects of priming time (5, 30 or 60?s), 10-MDP (10-methacryloyloxydecyl dihydrogen phosphate)-containing primer’s concentrations (0.5, 1, 5, 10 and 20% (w/w)) and two neutral primers (5% (w/w) of 10-MDP-Na or EDTA-2Na) on bovine enamel microtensile bond strength (μTBS) using a novel prime-and-rinse approach. After priming, the enamel surfaces were thoroughly water-sprayed and dried before resin composite was placed. There was a significant influence of primer’s concentrations and priming time on bovine enamel μTBS when 10-MDP-containing primers were used (p?<?0.001), revealing the optimal priming time (30?s) and the best combination (priming with 20% of 10-MDP for 30?s). The prime-and-rinse approach might be an innovative supplement to contemporary dental adhesive procedures. The neutral primer (5% of 10-MDP-Na) produced moderate enamel μTBS on highly polished enamel surfaces, while another neutral primer (5% of EDTA-2Na) failed, suggesting that chemical bonding of 10-MDP to enamel hydroxyapatite crystallites could yield detectable bond strengths on smooth enamel surfaces.     

一次搪耐酸搪瓷界面过渡层结构研究

采用合理配方设计,使用一次涂搪工艺,制备出了同时具有优良密着性能和耐酸性能的搪瓷板。采用扫描电子显微镜和能谱仪对一次搪耐酸搪瓷板界面显微结构和元素进行分析,研究结果表明,密着性能优良的一次搪耐酸搪瓷界面呈现咬合齿轮状,元素分析表明瓷层元素和金属元素相互扩散,相互渗透,在性能上表现为密着强度优良。