电镀方法

电镀方法包括:(1)制备一个表面有导通孔的基体;(2)将基体在预处理溶液中浸泡,对基体进行预处理;(3)将基体在镀液中浸泡,基体与阳极之间不施加电压,将镀液替代导通孔内的预处理溶液;(4)对基体     

专利

正一种电致驱动形状记忆聚酰亚胺的制备方法公开号:CN105542205A公开日:2016-05-04申请人:哈尔滨工业大学摘要:一种电致驱动形状记忆聚酰亚胺(PI)的制备方法,它涉及一种PI的制备方法。本发明的目的是要解决现有制备的形状记忆PI在特定应用时进行直接加热困难的问题。方法:(1)制备二胺混合溶液;(2)制备无规共聚聚酰胺酸;(3)制备含有碳纤维的无规共聚聚酰胺酸溶液;(4)热酰亚胺化,     

共聚改性尼龙MXD6的制备与表征

以己二酸、间苯二甲胺、己内酰胺、尼龙66盐、尼龙1010盐为原料,通过熔融缩聚合成了MXD6以及MXD6/6、MXD6/66、MXD6/1010三种共聚尼龙。通过傅里叶变换红外分析了其化学结构,采用差示扫描量热法和热失重法分析其热性能,通过动态热机械性能测试分析了其储能模量及玻璃化转变温度,并测试了力学性能。结果表明:(1)共聚改性尼龙MXD6具有很好的热稳定性;(2)共聚改性尼龙MXD6的熔点和玻璃化转变温度低于尼龙MXD6;(3)通过与脂肪族尼龙共聚,得到的共聚改性尼龙MXD6具有更好的韧性。     

最新专利

正一种共聚改性低熔点尼龙纤维的熔融直纺方法公开号CN 111304771A/公开日2020-06-19/申请人浙江恒澜科技有限公司本发明的特征在于:(1)将已内酰胺、共聚改性组分、封端剂、水和催化剂加热混合配料;(2)将混合物加热开环,进行预缩聚、终缩聚反应和脱挥;(3)纺前脱挥,产物直接输送至纺丝线进行纺丝,获得共聚改性低熔点尼龙纤维。本发明通过加入共聚改性组分,破坏尼龙分子链的规整性,降低尼龙分子链间的氢键密度以及结晶度,从而降低尼龙熔点。一种有色聚乳酸长丝的生产工艺及装置公开号CN 111321482A/公开日2020-06-23/申请人青岛叒米     

丙烯酸氟硅烷共聚树脂基防污涂层的制备与性能研究

以丙烯酰氧基三异丙基硅烷(TIPSA)、甲基丙烯酸三氟乙酯(TFEMA)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸甲氧基乙酯(2-MEA)为共聚单体,通过溶液聚合法合成出丙烯酸氟硅烷共聚树脂。通过红外光谱(FT-IR)对聚合物的结构进行了表征;通过X射线光电子能谱分析(XPS)探讨了共聚树脂在海水及海藻溶液浸泡前后的表面元素变化。通过将丙烯酸氟硅烷共聚树脂与50%松香溶液混合,以氧化锌、滑石粉为助剂,氧化亚铜为防污剂,制备了以丙烯酸氟硅烷共聚树脂为基体树脂的自抛光防污涂料,并通过浅海浸泡实验对防污涂料的防污性能进行了评价。结果表明,以合成的丙烯酸氟硅烷共聚树脂为基体树脂制备的防污涂料具有良好的实海防污性能。     

电镀方法和电镀产品

介绍了一种在铝合金基体表面电镀的方法,该方法包括如下步骤:(1)在铝合金表面浸锌;(2)在锌层表面碱性镀铜,然后再酸性镀铜;(3)在铜层上电镀铜-锡合金;(4)在铜-锡合金镀层上进行三价铬镀铬。施镀过程中使用无氰碱性镀铜液。     

市场趋向

正纳米抗菌复合材料市场潜力巨大纳米抗菌复合材料已成为抗菌材料研究领域主流方向。纳米抗菌复合材料可分为三大类:即无机材料、有机材料及天然材料为基体的纳米抗菌复合材料。具体的主要有下列类别:(1)AgO类纳米抗菌复合材料;(2)ZnO类;(3)TiO_2类;     

抗冲击共聚聚丙烯的结构与性能

对3种抗冲击共聚聚丙烯的力学性能进行了研究,并且采用动态力学分析、二甲苯溶出、溶胶凝胶渗透色谱和核磁共振等方法分析了抗冲共聚聚丙烯结构对其力学性能的影响。结果表明:提高共聚聚丙烯中乙丙橡胶相和聚丙烯基体之间的相容性,增加橡胶相含量,增大相对分子量并使其分布较窄,增加橡胶相中乙丙无规共聚物含量均有利于提高共聚聚丙烯的冲击强度。     

聚丙烯／PE-g-MAH／纳米SiO2复合材料性能研究

以PE-g-MAH(马来酸酐接枝聚乙烯)作为聚丙烯(PP)/纳米二氧化硅(SiO2)共混物的增容剂,通过不同的加工工艺制备了聚丙烯/PE-g-MAH/纳米SiO2复合材料,考察了不同处理方法及用量的纳米SiO2对PP基体的影响。结果表明:经表面处理,用量为4％的纳米SiO2和3％PE-g-MAH协同作用对PP的改性效果最好,冲击强度提高30％,弯曲强度提高10％,而改性PP的拉伸强度与未改性PP保持一致,且对嵌段共聚聚丙烯(PP-B)的改性效果优于无规共聚聚丙烯(PP-R)。同时,PP/PE-g-MAH/纳米SiO2复合材料的耐热性得到明显提高,较PP基体提高22℃,增幅为20％。     

番木瓜脂肪酶的应用前景

介绍了番木瓜脂肪酶的来源、特征和应用。番木瓜脂肪酶(CPL)作为一种水解酶可以和与水不溶的天然番木瓜蛋白酶的残片紧密结合,主要有以下应用:(1)通过对脂肪酸和油酸sn-3选择性进行修饰,生成短链的脂肪酸;(2)在有机相中催化多种酸和醇进行脂化反应;(3)对非甾体的抗菌药和人工合成氨基酸进行消旋体拆分。     

Effect of polishing method on surface roughness and bacterial adhesion of zirconia-porcelain veneer

The purpose of this study was to evaluate the effect of various polishing methods on surface roughness of zirconia-porcelain veneer and to correlate the findings with early bacterial adhesion. The study specimens were glazed (control group), glazed after fine polishing (glazed group) and polished with Exa Cerapol (Cerapol group) or with Shofu porcelain adjustment kit (Shofu group) (n =20). Surface roughness was then measured using profilometer and scanning electron microscope (SEM). After artificial saliva coating, the specimens were incubated in Streptococcus mitis suspension for 4 h at 37 °C. Adherent bacteria were quantified from SEM images. Streptococcal viability was assessed by LIVE/DEAD staining kit and fluorescent microscope. There were significant differences in surface roughness according to polishing method and surface material. Relatively smoother surfaces were found in zirconia surfaces and glazed porcelain surfaces. There were also significant differences in bacterial adhesion according to polishing method and surface material. Cerapol group showed minimal bacterial adhesion with more dead cells when compared to other groups. A positive correlation between surface roughness and bacterial adhesion was found in glazed porcelain surface and a negative correlation in zirconia surface of Cerapol group, both with no statistical significance. Within the limitations of in vitro study, surface roughness and bacteria adhesion were significantly influenced by polishing method and surface material. Also, there was a positive correlation and negative correlation between surface roughness and bacterial adhesion in glazed porcelain surface and in zirconia surface of Cerapol group, respectively.     

对应分析在景德镇历代瓷胎配方演变规律研究中的应用

应用对应因子分析技术分析了景德镇历代瓷胎化学成分数据,结果表明,景德镇古瓷胎配方演变过程可分为三个阶段,即五代十国和宋代为第一阶段;元代和明代为第二阶段;清代为第三阶段。瓷石掺和高岭土的制胎技艺始于元代,成熟于明未清初。在第一阶段内,瓷胎基本是由单一瓷石配制而成;第二阶段内,单一瓷石制胎与瓷石掺和高岭土的制胎工艺同时并存;第三阶段内,瓷胎配方几乎完全属于瓷石掺和高岭土的二元配料体系。     

Influence of Test Methods on Fracture Toughness of a Dental Porcelain and a Soda Lime Glass

The aim of this study was to investigate the influence of the test method on fracture toughness of a dental porcelain and a soda lime glass. Three methods were used to determine fracture toughness: the indentation strength (IS) by bending, chevron-notched beam (CNB), and the single-edge-notched beam (SENB). In the IS method, the ratio of elastic modulus to hardness ( E / H ) in the formula was determined by two methods: individual measurement for E and H (IS_M) as well as direct estimation from Knoop's indentation method (IS_K). The tested materials were a dentin porcelain, a traditional feldspar-based leucite-reinforced glass ceramic (Carrara Vincent), and a soda lime glass. Carrara Vincent showed a higher toughness ( P <0.01) than glass with all three test methods. The toughness values manifested significant differences between the methods used ( P <0.01). The two-way analysis of variance suggested that the materials tested and the test methods used had interaction effects, which statistically means that differences in materials and methods influenced the comparability of the toughness result. In this study, a first step was made to compare different toughness test methods by testing the toughness of a traditional feldspar-based leucite-reinforced glass ceramic and a soda lime glass that has a homogeneous microstructure. An interaction effect of the method and the material used was shown. As a consequence, none of the methods tested is suitable as a universal fracture toughness test method. Further research is needed to investigate more extensively the influence of material composition on the fracture toughness test methods' comparability.     

Structural-phase changes in iron-bearing impurities in the process of porcelain formation

The methods of Mössbauer spectroscopy, electron-spin-resonance (ESR) spectroscopy and magnetostatics are used for studying the structural and phase transformations of iron-bearing impurities in the process of porcelain formation. It is established that iron-bearing microinclusions break up in high-temperature (up to 1400°C) firing, leading to redistribution of iron ions over the volume of the material.     

CHEMICAL DURABILITY OF PORCELAIN ENAMELS *

The resistance of representative porcelain enamel surfaces to the chemical attack of different concentrations of various solutions was investigated in considerable detail. Cylindrical cup-shaped samples were coated with (1) a ground coat, (2) a white fluoride cover enamel, (3) a white antimony cover enamel, (4) a white zirconium cover enamel, (5) an acid-resistant white cover enamel, (6) a sign blue cover enamel, (7) a blue zirconium enamel, and (8) a chemical acidproof blue cover enamel. The loss in weight of these enamel surfaces, after exposure to chemical attack, was determined at definite time intervals. The solutions studied consisted of different concentrations of the inorganic acids, alkalis, several organic acids, as well as selected salt solutions at both room and boiling temperatures. Numerous curves are presented showing the comparative chemical durability of the various porcelain enamel surfaces in which the cumulative loss in weight is plotted against time. Several photomicrographs show the nature and type of chemical attack on the different surfaces. The porcelain enamel surfaces showed considerable variation in their resistance to the chemical attack of the various solutions. All of the porcelain enamels were, in general, resistant to attack at room temperature by the alkali and salt solutions. The acid-resistant and acidproof enamels were resistant to the action of both inorganic and organic acids at room and at boiling temperatures; a wide variance, however, was shown in the comparative acid resistance of the non-acid-resisting enamel to the attack of either organic acids or inorganic acids at room temperature. AU porcelain enamels showed equally low resistance to boiling alkali solutions, but some of the enamel surfaces were attacked markedly by the boiling salt solutions.     

传统粉彩颜料及其无公害化

简要总结了景德镇传统名瓷一.粉彩瓷的发展历史，叙述了传统粉彩颜料的种类、使用原料、制备方法、生产工艺。总结了国内为降低粉彩瓷铅溶出量所做的工作及其局限性，并分析了当前粉彩瓷面临的问题，对无公害粉彩颜料的研究提出了思路和要解决的关键问题。     

Feedstock Formulations for Direct Consolidation of Porcelains with Polysaccharides

Direct-consolidation methods are becoming well-established forming techniques for advanced ceramics, because of their advantages in terms of shape capability. These advantages could also be exploited to consolidate traditional ceramics, such as stoneware or porcelain pottery requiring handles, which could be potentially manufactured in a single step. The most limiting factor in the transfer of these technologies from advanced to traditional ceramics is related to the moderate solids loading usually achievable with clay-based suspensions. In this work, new porcelain feedstocks are proposed that use either milled rejected pieces (MRP) of porcelain or a kaolinitic stoichiometric mixture of SiO₂ and Al₂O₃, i.e., pseudokaolin (PK). The replacement of the clay component by MRP or PK makes it possible to obtain 60 vol% aqueous porcelain suspensions, which can be directly consolidated using a relatively low amount (1 wt%, based on liquid volume fraction) of a mixture of polysaccharides. Steady shear viscosity measurements show that these highly concentrated suspensions are fluid enough for pouring operations. The green and presintered bodies show similar values of shrinkage and relative density, because of the low amount of organic additives used. The total replacement of the clay component in the starting composition enables a decrease in the firing temperature. Otherwise, for a given firing schedule, the enhancement of quartz dissolution in the glass phase and the decrease of the aspect ratio of mullite needles lead to an increase of the pyroplastic deformation index.     

关于瓷件金属化后发黑缺陷的探讨

本文针对九五瓷瓷件在经过金属化炉后，瓷件及釉面经常会出现表面发黑这一缺陷，从实际生产角度出发，分析了所选择的原料、釉方的温度、瓷件的生产过程、金属化炉内的气氛等影响因素，提出了解决这一缺陷的途径，供同行参考。     

In situ synthesis of orange rutile ceramic pigments by non-conventional methods

Different precursor-mixtures of orange Cr,Sb-TiO₂ ceramic pigment have been obtained by non-conventional methods (heterogeneous ammonia coprecipitation, urea homogeneous coprecipitation, PECHINI polyester method and an original aqueous–organic coprecipitation method in water–diethylenglycol medium) in order to produce in situ the pigment through the ceramic body firing. The pigmenting performances of powders were appraised in two cases: (a) as ceramic pigment for glazed porcelain stoneware and (b) as ceramic inks for screen printing of porcelain stoneware. Samples were characterised by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV–vis-NIR spectroscopy by diffuse reflectance method, CIE-L*a*b* colour parameters, BET specific surface area and crystallite size measured by the Scherrer method. The colouring performance of raw powders obtained by non-conventional methods in glazed porcelain stoneware improves that of the ceramic samples fired at 1100 °C used as reference. TEM observations indicate nanostructured powders with pigmenting performance depending on factors such as their specific surface area (BET), the crystalline phases detected by XRD (e.g. anatase–rutile presence) and their crystallite size (Scherrer measurements). Ammonia coprecipitated samples, both in water and in water–diethylenglycol medium without surfactant addition, or modified by the addition of sodium dodecyl sulphate as surfactant, stand out by their colouring performance.     

Effects of magnesium oxychloride and silicon carbide additives on the foaming property during firing for porcelain ceramics and their microstructure

Porcelain green bodies that were prepared with a porcelain tile powder as a major raw material, and magnesium oxychloride (MO) and silicon carbide (SiC) as additives were fired at 1000–1200°C. Effect of the additives on the foaming property for porcelain ceramics and its microstructure was quantitatively investigated to clarify the foaming origin of polished porcelain waste during firing. The experimental results show that a small amount of the mixture of both MO and SiC added into the porcelain green body causes the body foaming during firing more significantly, compared to the addition of either SiC or MO. The foaming of porcelain green body with only SiC is more remarkable than that of the porcelain green body with only MO at the same content and firing conditions. The MO accelerates the foaming of porcelain green body with SiC during firing. In addition, the foaming mechanism was also discussed.