高含硅量的硼硅酸盐玻璃在熔制时所产生的缺陷

众所周知,“派莱克斯”玻璃、高含硅量的硼硅酸盐玻璃比另外一些玻璃更难进行均质地熔制;因为在熔制时,经常产生条纹、疙瘩和结石。本文的目的是为了探讨在商用“派莱克斯”玻璃制品的熔制过程中,产生条纹、疙瘩和结石的原因。所采用的实验设备是离心机、干涉仪和应变仪。     

有效解决玻璃制品条纹缺陷的装置

玻璃制品上的条纹是玻璃制品生产过程中容易产生的三大缺陷之一.产生条纹的原因较多,大都可以通过搅拌而消除.也有通过常规搅拌方法解决不了的条纹,分析了产生这种条纹的原因,推介一种解决这种条纹的装置,它能大大减轻或消除这种条纹,提高产品质量,提高产品合格率,从而提高产量.     

日用玻璃制品条纹缺陷的产生原因及解决措施

叙述了条纹的形成和性质,分析了条纹的折射率和膨胀系数变化及所产生的应力。指出条纹在玻璃熔窑各个区域中产生的原因。针对国内熔窑产生条纹的原因进行了分析,提出改进措施。     

锦纶6染色织物条纹产生的原因及控制方法

锦纶6染色织物具有耐磨、强度高、质轻等优点,广泛应用于运动服装和休闲服装。织物染色中最常见的质量问题是产生深浅不一条纹。本文从原料的制备、纤维的成形、织物的织造三个方面讨论了条纹产生的原因。结构性的条纹是在织造过程中产生的;聚集态性的条纹多数是纺丝过程由于纺丝工艺的变动产生的;聚合物合成工艺的波动会产生化学性的条纹。在染色过程中通过合理选择染料、降低染色的始染温度、调节染液的pH值等工艺因素,可避免条纹的产生。     

颜色玻璃条纹的排除

分析了颜色玻璃条纹产生主要原因之一——火焰气氛波动导致“不动层”厚度不稳定，提出了防止条纹产生的措施，指出要消除颜色玻璃的条纹必须注意稳定火焰气氛。     

浅析汽车油漆修补中斜条纹缺陷的解决

通过对现场补漆的斜条纹缺陷进行研究分析,确定了产生的斜条纹质量缺陷的原因,并通过临时措施,解决斜条纹缺陷的质量问题。     

玻璃结石及其有关工艺因素述评

玻璃生产中缺陷是经常发生的。气泡、条纹、结石或时有所见,或时现严重。特别是结石经常或大量的出现,将严重地妨碍生产,使工厂经济遭到损失。为了提高玻璃生产的质量,人们对结石形成的机理进行了研究,企图从中找出避免这种缺陷的办法,这项工作对指导实际生产具有很大的意义。     

改善Z型条纹 提高斑马角

阐述了浮法玻璃条纹形成的机理,介绍了生产中常见的条纹类别及成因,着重对因循环流弱产生的条纹进行了分析,提出了相应改善措施。     

玻璃的脆性(三)

玻璃的缺陷可分为纳观缺陷、微观缺陷和宏观缺陷。纳观缺陷为纳米尺度的缺陷,指玻璃结构缺陷,包括微相、微不均、配位不全,空穴等。微观缺陷指微米尺度缺陷,主要为玻璃表面Griffith裂纹。宏观缺陷为玻璃制造中产生的缺陷,如气泡、结石、条纹,以及使用过程中的损伤。这些缺陷的存在增加玻璃的脆性。描述了玻璃表面Griffith裂纹的尺寸、分布以及形貌。     

石英晶体的条纹缺陷及其对透过率的影响

采用正交偏光条纹检测仪观察了水热法生长的光学石英晶体中的条纹缺陷,分析了光学石英晶体中条纹缺陷产生的原因和对晶体样品的透过率的影响。结果表明:晶体中的条纹缺陷主要是由在生长过程中籽晶中缺陷的遗传和高压釜中局部生长条件变化引起的。有条纹和无条纹缺陷晶体在400～800nm波段存在最高吸收峰,800～2500nm波段存在最低吸收峰。有条纹缺陷和无条纹缺陷晶体样品的透过率存在0.64%的差异。     

钢渣复合取代矿粉、砂和石用作混凝土掺合料与骨料及其性能分析

用风淬渣粉取代矿粉、电炉渣砂取代混合砂、电炉渣石取代碎石制备混凝土,分析了混凝土的内照射指数、外照射指数、f-CaO含量、沸煮膨胀值、比表面积、密度、含水率、容重、含泥量、泥块含量、坍落度、抗压强度及其化学组成、矿物组成与微观形貌,研究了钢渣的安全性与稳定性及风淬渣粉取代矿粉、电炉渣砂取代混合砂、电炉渣石取代碎石与钢渣复合取代矿粉、砂和石对混凝土性能的影响。结果表明,风淬渣粉、电炉渣砂和电炉渣石的安全性与稳定性满足国标要求,可用于混凝土。当风淬渣粉取代20wt%矿粉、电炉渣砂取代10wt%混合砂和电炉渣石取代20wt%碎石时,混凝土的性能最优。钢渣复合取代矿粉、砂和石的比例合适,可改善混凝土的界面结构密实度,尤其能提高混凝土养护后期的强度。     

7.00R16LT 14PR公路型全钢轻型载重子午线轮胎的开发

介绍7.00R16LT 14PR公路型全钢轻型载重子午线轮胎的开发。结构设计:外直径768 mm,断面宽198 mm,行驶面宽度148 mm,行驶面弧度高4.8 mm,胎圈着合直径404.1 mm,胎圈着合宽度152 mm,断面水平轴位置(H₁/H₂)0.9907;采用有限元分析方法,通过调整轮胎外轮廓曲线解决冠部花纹异常磨损问题;花纹沟壁采用单边双层设计,花纹沟底采用偏心设计,可有效改善花纹沟夹石子问题。施工设计:胎体采用3×0.22/9×0.20CCHT钢丝帘线,带束层采用2层2+7×0.30ST超高强度钢丝帘线,以提升轮胎的高速性能和承载性能;胎面配方优化设计后可提高轮胎的耐磨及抗刺扎性能。成品轮胎性能试验结果表明,成品轮胎充气外缘尺寸及强度、耐久和高速性能均符合设计要求。     

Criteria and methodology for the evaluation of conservation interventions on treated porous stone susceptible to salt decay

Susceptibility of stone to salt decay is directly related to its microstructural and mechanical characteristics. In the present work, a porous stone from a quarry in Cyprus was examined. Samples of this stone were consolidated and protected with certain conservation materials. The modification of microstructural characteristics of the stone was evaluated by mercury intrusion porosimetry, while its mechanical characteristics were measured by compressive and bending strength tests. From these data, the susceptibility of Cyprus stone to salt (NaCl) decay was estimated. The values of crystallization pressure of NaCl were calculated and compared to the experimentally measured compressive and tensile strength of the stone, in order to examine the probability of stone disruption due to salt crystallization. The development of the phenomenon after coarse pores’ filling with crystals, i.e. crystallization of salts in capillaries or mechanical failure of the stone, was determined by thermodynamic analysis. Additionally, artificial weathering tests of marine salt spray were performed for the evaluation of stone’s durability after the conservation. The treated stone proved to be resistant to salt decay, as it presented ameliorated microstructural and mechanical characteristics, concerning decay due to soluble salt crystallization. The most possible thermodynamic scenario was small pores repletion with crystals, avoiding mechanical failure of the stone.     

掺花岗岩石粉的管桩高强混凝土微结构和力学性能研究

本文采用蒸压养护方式制备管桩高强混凝土,以相同配合比的标准养护混凝土为对比组,分别研究磨细砂和石粉双掺时石粉取代率(花岗岩石粉/(花岗岩石粉+磨细砂),质量比)和石粉单掺时石粉掺量(花岗岩石粉/(花岗岩石粉+水泥),质量比)对管桩高强混凝土强度的影响,并通过XRD、ESEM等方法研究掺花岗岩石粉的管桩高强混凝土水化产物的种类及形貌特征。结果表明:蒸压养护下,混凝土强度随石粉取代率和石粉掺量的增加均先增大后减小, 石粉取代率为25%和石粉掺量为20%时混凝土强度分别达到最大值。由于花岗岩石粉中的SiO₂在蒸压条件下会与水泥水化产物Ca(OH)₂发生火山灰反应并生成托勃莫来石,使混凝土更为密实,因此相同配合比条件下蒸压养护3 d的混凝土强度高于标准养护28 d的混凝土强度。     

Preparation of epoxy resin elastic particles and their application in oil well cement

To solve the problem of high brittleness and easy cracking of cement stone, epoxy resin powder elastic particles (HEEP) were developed to improve the elasticity of cement stone. HEEP was prepared from epoxy resin and trimeric anhydride by solution polymerization. The surface wettability and particle size of HEEP were analyzed by contact angle test and laser particle size analysis respectively. Mechanical performance tests, scanning electron microscope (SEM) analysis and x-ray diffraction analysis were conducted on the cement stone containing HEEP. The results showed that HEEP was the target product, with a hydrophilic surface and a water contact angle of 75.2° on the HEEP surface. The particle size distribution of HEEP was uniform, and the median particle size was 36.5 μm. The initial decomposition temperature of HEEP was 300°C, indicating a good thermal stability. The stress–strain curve showed that when the HEEP dosage was 3%, 6%, and 9%, the elastic modulus of the cement stone was 6.382, 4.017, and 3.148 GPa, respectively. Compared with the blank cement without HEEP, the elastic modulus was reduced by 28.3%, 54.9%, and 64.6%, respectively. This showed that HEEP could effectively improve the elasticity of cement stone. In addition, the compressive strength and flexural strength of cement stone containing HEEP can meet the requirements of on-site applications. SEM analysis of cement stone showed that HEEP was well filled in cement stone. When the cement stone was subjected to complex stress, HEEP could effectively buffer and disperse the stress, thereby enhancing the resistance of cement stone to external force impact.     

硅质耐材结石与泥料结石的形成与鉴别

通过从宏观到微观的结构观察以及它们与钠钙硅酸盐玻璃交代反应的不同,对硅质耐材结石与泥料结石进行分析以资鉴别。     

硅灰石的加工及其在涂料中的应用

阐述了硅灰石的结构及特点。介绍了硅灰石的加工方法,及其在内外墙乳胶漆中的应用。     

Boehmite/methacrylic nano-composites as protective coatings for natural stones: comparison between sunlight and UV photopolymerization cure reaction

The protective properties of two innovative, experimental nano-composite coatings which are mainly intended for the protection of cultural heritage stone artifacts were compared. The decay of artworks, monuments, and buildings made of stone materials is a natural and irreversible process. In order to protect stone artworks and buildings from natural decay, it is necessary to reduce the penetration of water into porous substrates by applying a highly hydrophobic protective coating on the stone surface. The performances of two nano-composite coatings containing an organo-modified boehmite nano-filler, applied on calcareous stone substrates typical of Apulia region (leccese stone, PL and gentile stone, PG), and activated by UV or sunlight radiations, were compared in order to establish the more suitable product for the specific stone substrate.     

废弃石粉对低密度聚乙烯非等温结晶过程以及拉伸性能的影响

将废弃石材加工过程中的副产物石粉引入到低密度聚乙烯(LDPE)中,实现对废弃石粉的回收利用。采用了差示扫描量热法(DSC)、广角X射线衍射(XRD)以及电子万能试验机研究了LDPE/石粉复合材料的结晶动力学、结晶形态以及力学性能。结果表明:石粉对于LDPE的结晶过程影响有限,复合材料与聚合物的结晶峰顶温度以及半峰宽相差无几;复合材料的结晶结构与结晶形态与聚合物相比无明显变化;在石粉含量为20%(质量分数)时,复合材料的拉伸屈服强度仍然保持了与聚合物几乎相同的数值。研究结果显示,石粉作为一种惰性填料,完全能够用于LDPE的填充改性。     

Hybrid effect,mechanical properties and enhancement mechanism of oil-well cement stone with multiscale silicon carbide whisker

Cement-based materials typically have a relatively high compressive strength and a relatively low tensile strength. In this paper, multiscale silicon carbide whiskers (SW) were used to improve mechanical properties of oil-well cement stone. The structure and properties of whisker cement stone were analyzed via mechanical testing and cement sheath integrity. The results demonstrated that multiscale SW mixing showed a positive hybrid effect and could effectively improve the compressive strength, the flexural strength, and the splitting tensile strength of oil-well cement stone by 8.96%, 137.44% and 27.96%. The modulus and porosity of the whisker cement stone significantly reduced. The filling effect, whisker pinning, the pullout, and the whisker bridging were regarded as effective mechanisms for the addition of SW when improving the mechanical properties and microstructures of oil-well cement stone.