影响涂装前脱脂工序处理质量的因素

1工件表面的脂类和油污 钢材及零件在储运加工和热处理时分别要使用防锈油脂、拉延油,切削时接触乳化液冷却油,其上的油脂还会和灰尘等杂质掺和在一起.这些油污不仅阻碍磷化膜的形成,还影响涂层的结合力、干燥性能、装饰性能和耐蚀性,必须予以除去.     

用氧阀门脱脂处理方法及验收标准

阐述了氧气阀与润滑脂接触的危险,指出了氧气阀脱脂的必要性.提出现有的阀门脱脂方法并对比各自优缺点,给出脱脂处理过程中需要注意的安全问题,指出脱脂介质的清除方法,最后给出阀门脱脂的验收标准.     

超声波协同处理对桉木抽提物及尺寸稳定性的影响

目的 探究不同频率超声波辅助去离子水溶液的抽提处理对巨尾桉木抽提物得率、成分以及试件尺寸稳定性的影响。方法 分别以频率为0,25,59 kHz的超声波辅助去离子水、质量分数为1%的盐酸溶液、质量分数为1%的氢氧化钠溶液,在60 ℃条件下抽提巨尾桉试件2 h,计算抽提物得率,采用GC/MS检测抽提物成分,测算试件的湿胀率和抗湿胀率。结果 在频率为59 kHz的超声波辅助下,氢氧化钠溶液（1%）处理组的抽提物得率最高,达7.67%;3种溶液处理所得抽提物成分差异虽较大,但超声波辅助抽提时,烷烃类、酯类物质的种类及相对含量变化明显;抽提处理提高了试件的尺寸稳定性,59 kHz的超声波辅助盐酸溶液（1%）处理组试件的抗湿胀率最高,达到65.39%。结论 超声波协同热水溶液的抽提处理能够提高巨尾桉尺寸稳定性,且有利于抽提物的抽出。     

3D打印氧化铝陶瓷的气氛脱脂热处理工艺研究

脱脂热处理工艺对于3D打印陶瓷的成形质量具有重要的影响。目前光固化3D打印制备得到的氧化铝生坯经过在空气中的脱脂热处理工艺后烧结最终得到的氧化铝陶瓷存在的微观裂纹等缺陷, 将导致其力学性能较差。本工作研究了基于数字光处理(Digital light processing, DLP)技术的氧化铝陶瓷打印热处理工艺, 将3D打印制备得到的氧化铝陶瓷生坯分别在空气与氩气中脱脂后比较其宏观形貌, 发现在空气下脱脂的氧化铝生坯存在微观裂纹。再将脱脂后的生坯在空气下烧结得到氧化铝陶瓷, 并对其微观形貌和宏观性能进行表征, 发现在氩气下脱脂的氧化铝陶瓷平均晶粒尺寸要比直接在空气中脱脂得到的氧化铝陶瓷平均晶粒尺寸大, 而且晶粒结构致密, 无明显气孔和杂相, 而且具有更高的抗压强度。这说明在氩气中脱脂后烧结得到的氧化铝陶瓷性能更好。在氩气中脱脂的氧化铝致密度最高可达到96.72%, 抗压强度可达到761.7 MPa, 相比于只在空气中脱脂的氧化铝陶瓷性能得到显著提升。     

粉末装载量和气氛对MIM不锈钢脱脂过程的影响

研究了粉末装载量和气氛对金属注射成形（ＭＩＭ）不锈钢脱脂过程的影响，粉末装裁量高，脱脂速率低，粉末装载最低，脱脂速率高，在真空环境下，由地石蜡的饱和蒸气压大于环境威协答独即使在８０～１００℃的低温情况下，粘结剂也能比较显著地被脱除。     

脱脂紫茎泽兰细度对水凝胶溶胀动力学的影响

以不同细度粉末状脱脂紫茎泽兰(EA)为原料,研究在相同的接枝共聚条件下所得的水凝胶的溶胀行为。实验表明:在45～75μm范围内,随着原料颗粒细度的降低,所得相应凝胶的溶胀速率和溶胀度均增大,水分子在凝胶中的扩散行为可用non-Fickian扩散来描述;在30～45μm时所得凝胶的溶胀过程符合Fickian扩散规律。通过Beren-Hopfenberg微分方程,计算得到凝胶吸液值大于60%时的溶胀扩散常数。利用Arrhenius公式计算得到相应的活化能均在69.0～89.0kJ·mol-1范畴内,且随原料颗粒细度的减小,凝胶Ⅱ-1-Ⅱ-4的Ea值呈下降趋势;而Ⅱ-5的活化能略高于Ⅱ-4,但仍小于其他凝胶的Ea值。     

工艺管道脱脂、酸洗与钝化的处理与改进

主要对广州广钢气体厂一期工程中工业管道的酸洗、脱脂、中和、钝化等工序的施工工艺进行介绍,并结合施工现场及当地气候环境,分析管道及管件在酸洗、脱脂、中和、钝化过程中及其后现场保护所遇到的问题,提出了改进措施。     

静态径向加载速率对樟子松吸能特性的影响

目的研究樟子松在不同静态径向加载速率作用下的能量吸收特性。方法采用横纹径向压缩实验。结果在不同加载速率的作用下,应力-应变曲线都呈现出3个阶段,即弹性阶段,应力平台阶段以及密实化阶段。樟子松存在明显的应变速率敏感性,随着加载速率的增加,应力-应变曲线的应力平台阶段不断上升。当应变为0.06,加载速率为1 mm/min时,应力为4.38 MPa;当加载速率为10和30mm/min时,对应的应力分别为4.71和6.56 MPa。樟子松具有优良的吸能能力,其能量吸收效率可以达到0.7~0.8。其缓冲系数曲线呈"L"型,随着应变的增加缓冲系数不断减小,但受加载速率的影响不大。结论不同加载速率对樟子松的能量吸收特性有一定的影响。     

测定中间相含量的图解处理法

前言中间相含量的测定对炭化过程的研究及炭纤维生产过程中的工艺控制等等都是十分重要的。 Chwastiak等通过相界面溶剂浸蚀辨别     

钨合金正挤压棒坯溶剂脱脂缺陷的形成与控制

粉末挤压成形技术是制备大长径比钨基高比重合金棒材最有效的方法之一,而脱脂过程直接影响着样件缺陷控制及合金力学性能的改善效果.探讨了Φ12 mm和Φ15 mm钨基合金正挤压棒坯溶剂脱脂缺陷的形成及其控制,采用可控恒温仪调控溶剂脱脂速率,利用数码相机和扫描电镜分别对棒坯表面形貌和微观结构进行观察.结果表明：钨基合金正挤压棒...     

The effect of accumulation of cathodic decomposition on the anodic conversion of sulfide ions to sulfur in a continuous extractive electrochemical reactor

Abstract

This paper presents an intelligent digital filter synthesis system which consists of a user‐friendly graphic I/O interface, a synthesis program designing filter coefficients, an intelligent hardware generation system and a simulator including time and frequency domain simulation. Users need only to specify the filter type, filter specifications, sampling rate requirement and some parameters through the graphic interface. The filter response and the simulation results can be immediately shown on the screen. The graphic interface is based on the X Window System and therefore provides a network‐transparent and vendor‐independent operating environment for the system. The synthesis system is targeted for two main types of digital filter: FIR and IIR. An automatic partition algorithm on FIR is developed to meet the user's sampling rate requirement. The optimal cascade architecture of biquad‐based IIR with programmable coefficients is also derived. The final circuit designs under economic bitwidth are generated by the GDT system and further layouts can be generated.     

锑掺杂量对ATO纳米颗粒结构及其导电性能的影响

以SnCl4.5H2O和SbCl3为主要原料,采用sol-gel法制备了锑掺杂二氧化锡（ATO）纳米粉体。分别利用FESEM、XRD、FT-IR、XPS及四探针电阻仪对粉体形貌、晶体结构、元素组成和粉末电阻进行表征,考察Sb掺杂量对ATO粒子晶体结构、晶粒尺寸和导电性能的影响。结果表明所制备的ATO为（110）面择优取向的四方相锡石结构的纳米颗粒,当Sb掺杂量为15%（摩尔分数）时,ATO具有最小的粉末电阻率（12.85Ω.cm）。当Sb掺杂量≤28%时可得到完全掺杂的ATO,ATO的导电性与其中的Sb5＋离子浓度有关,而且Sb含量在28%以下可能存在一个阈值,有利于固溶在SnO2晶格中的Sb形成Sb5＋,使载流子浓度达到最大,因而表现出最佳的导电性能。     

Si含量对反应烧结SiC陶瓷热电性能的影响

采用可控溶渗反应烧结法制备了致密SiC陶瓷，研究了不同Si含量对反应烧结SiC陶瓷热电性能的影响。经研究发现，反应烧结SiC陶瓷中Si的存在使SiC陶瓷的电阻率急剧下降，大大改善了SiC陶瓷的电学性能；同时Si也改变了SiC陶瓷塞贝克系数随温度的变化趋势，即没有添加Si元素的SiC陶瓷的塞贝克系数随温度的升高逐渐增大，而添加Si元素的SiC陶瓷的塞贝克系数随温度的升高逐渐减小；总的来看，随着Si含量的增加，SiC陶瓷的塞贝克系数扣电导率不断增大，因此Sic陶瓷的功率因子不断提高，而且随着温度的升高，Si含量对SiC陶瓷热电优值的影响越来越明显，当含量为15％时，材料的热电优值是SiC烧结体的30倍。     

Effects of Silicium Dioxide on Drug Release from Suppositories

Abstract

Silica gel is frequently introduced into lipophilic excipients for suppositories as a viscosity agent, to prevent drug sedimentation in the melted mass, and to decrease release rate. The effect of silica gel (Aerosil 200) concentration on the availability of some drugs frequently used in suppositories in different unitary doses was studied. When silica gel concentration in the excipient was increased, a decrease in aminophylline and aminophenazone release rate was observed. Paracetamol in small unitary doses has shown a tendency to increase release rate at higher silica gel concentrations. This behavior was even more evident in suppositories containing promethazine hydrochloride, while for those containing benzydamine hydrochloride the increase in release rate with increasing silica gel concentration was evident for all drug doses. However, the behavior was a consequence of the trend of suppository viscosity during drug release. As a consequence of both the drug and silica gel being discharged, the viscosity progressively decreased with an increased silica gel concentration. The effect on drug availability was conditioned by silica gel concentration, as well as the type and dose of the drug, which could act on the shape of the suppository inner structure that is responsible for viscosity and mobility of drug particles.     

碳含量对高合金铁基材料组织与性能的影响

研究了高合金铁基材料中碳含量对材料显微组织与性能的影响.采用光学显微镜、扫描电镜和能谱分析表明:碳含量对材料烧结密度和性能影响显著.热处理后,材料硬度上升,但强度和韧性下降.烧结时,碳含量增加,使液相量增加,晶界上的液相膜增厚,晶粒球化;碳化物大部分在晶界上析出,形成半连续网络组织.热处理后,由于部分碳化物的溶解,一些连续的网络组织断裂.实验得出,1250±5.°C烧结,碳含量为1.4%时,烧结致密化程度最高,相对密度达到96%,各项性能也达到最高.本实验通过合理控制碳含量,获得了高性能的铁基粉末冶金材料.     

液氮储罐中液氮氧含量超标的原因分析与处理

简介武钢氧气公司2套60000 m3/h空分设备液氮储存系统流程,介绍2000 m3液氮储罐中液氮氧含量超标的事故经过,分析了事故原因,阐述了相应的处理方法,最后总结了为保证液氮储罐中液氮氧含量不超标而采取的措施。     

Determination of the volume content of the components of an oil-water type emulsion from the parameters of an electromagnetic resonator

The variations of the main parameters of electromagnetic oscillations in the sensitive element (a resonator embedded in a pipeline) of a radio-frequency sensor under resonance conditions for flows of emulsion mixtures are determined and investigated. Algorithms for determining the volume content of the components of oil-water mixtures with an arbitrary degree of water mineralization are developed. __________ Translated from Izmeritel’naya Tekhnika, No. 9, pp. 60–65, September, 2007.     

马尾松边材基Sr1-xLaxFe12-xCoxO19铁氧体制备及磁性

以马尾松边材为模板,用sol-gel法制备出多层壁结构Sr1-xLaxFe12-xCoxO19(x=0～0.2)铁氧体样品。利用XRD、SEM、VSM对样品的结构、形貌、磁性进行了表征。结果表明锶铁氧体保留了木材的多层壁结构,壁厚约1～2μm,锶铁氧体微粒尺寸约在1～1.5μm,每个微粒水平连接构成管胞壁。样品的饱和磁化强度随x值增大而增加,矫顽力则随着x值增大先增大后减小。但平行壁方向(A方向)的矫顽力明显低于其它方向(B、C方向)。     

Foundations of content preparation for the web

The objective of this paper is to develop a model for content preparation of websites. Content preparation describes a process of web design that equally weighs the identification of information requirements with the presentation modes of that information. This paper focuses on what information should be available on the web instead of how the information should be presented. It reviews studies concerning: (a) credibility evaluation of printed media; (b) quality dimensions of information systems; (c) Internet domain-specific information needs. Based on the review, two key figures synthesise the aspects related to content preparation. First, the convergence hierarchy integrates domain-specific components into a general information structure. Second, the conceptual model proposed eight factors for effective content preparation. These factors are site, transaction, company, security, product, customer service, shipping and membership. It highlights specific content elements and yields major implications for a broad range of websites. Primarily, it establishes a foundation for developing methods to evaluate the effectiveness of content preparation for websites. Combining content preparation with usability methods will provide a comprehensive effectiveness evaluation of websites using the ISO 9241–11 (International Organization for Standardization, 1998. ISO 9241–11, Ergonomics requirements for office work with visual display terminals (VDTs)–Part 11 Guidance on usability. Geneva: ISO) framework. Also, it could act as a general guide of content preparation for websites.