预涂布干膜厌氧胶在螺纹连接件上的应用

本文从力的角度阐述了螺纹连接件机械锁固与化学粘接（即厌氧胶）锁固在机理上的区别，通过螺纹连接的模拟实验模型，揭示了预涂布干膜厌氧胶能有效提高螺纹连接件的销固性，密封性的内在实质。提出了颢响厌氧胶固化后的破坏扭矩的因素．理论和实际应用表明，厌氧胶技术可对螺纹连接件进行优良的锁固和密封，具有广阔的发展前景．     

ZY-800系列厌氧胶及其应用

厌氧胶是六十年代投入工业化生产的新材料,其主要成分是丙烯酸双酯,结构通式为: R为H或低级烷基,X为多元醇、二元酸、二元酚、磷或羟烷基胺等。这种化合物如再加上引发剂、促进剂、稳定剂、增稠剂和染料等,则可配成不同品种的厌氧胶。厌氧胶在工业上有着极其广泛的用途。ZY-800系列厌氧胶是我所研制的,由高分子物质构成的液态胶粘剂。     

二硫代磷酸O,O-二烷基酯-钼化合物的合成及其减摩性能研究

本文合成了由异磪基、异丁基、正戊基、正已基、正辛基和正癸基取代的二硫代磷酸O、O-二烷基酯及其双二硫物作为二齿硫配体与钼源化合物反应合成了油溶性硫-钼化合物。以1%浓度添加到矿物基础油中对极压减摩性能有显著改善。二硫代磷酸O、O-二正辛基酯-钼化合物具有最佳改进效果。     

邻苯二甲酸酯类润滑基础油摩擦学性能

在UMT-2型微摩擦试验机上分别测定邻苯二甲酸二异丁酯、邻苯二甲酸二正戊酯、邻苯二甲酸二正辛酯、邻苯二甲酸二异辛酯、邻苯二甲酸二壬酯、邻苯二甲酸二异癸酯在5~98 N载荷下的摩擦学性能。实验结果表明：在不同的载荷下,随着试验时间的延长,6种酯的摩擦因数都呈现下降趋势;邻苯二甲酸二异癸酯平均摩擦因数在各载荷下都最小,但是在低载荷下（5 N左右）波动较大;同一载荷下,直链酯的平均摩擦因数随着碳链长度的增加而降低,支链酯的平均摩擦因数变化无明显规律;同种酯的磨斑直径随载荷的升高而增加;同一载荷下,不同碳链长度的酯的磨斑直径变化没有明显的变化规律,醇碳链的延长并不能有效地控制磨损。     

煤油介质伺服机构油面电压与温度关系研究

伺服机构油面电压会随着环境温度的变化而变化,为了使煤油介质伺服机构在各种环境温度下均能正常工作,需要研究伺服机构油面电压与温度间的关系。根据液体热膨胀理论和现役型号伺服机构油面电压与温度间的经验公式,假设煤油介质伺服机构油面电压与温度间为线性关系。使用2台某型号煤油介质伺服机构进行了-35℃~+75℃的温度试验,获得了各温度点下的油面电压值。分别采用线性和二次多项式拟合的方法对油面电压值与温度间的关系进行了拟合,验证了油面电压值与温度间的线性关系,并根据试验数据推导了某型煤油介质伺服机构油面电压值与温度间的换算公式。     

厌氧胶粘接技术在机械设计中的应用

本文阐述了影响厌氧胶胶接强度的诸因素,并举了一些设计中的应用实例,通过对比说明,显示了厌氧胶粘接技术在机械设计中的应用的可行性、可靠性、技术性和经济性.     

厌氧型螺纹锁固胶在机械装配工艺中的应用

螺纹紧固胶件的松动对设备厂商和用户而言都是一个十分棘手的问题。文中就厌氧胶在装配过程中的紧固件松动问题进行了探索,对厌氧胶特点和厌氧胶在装配过程中的使用方法、效果进行了深入分析,对解决工程机械装配中紧固件防松问题有一定的参考价值。     

碳酸二异十六酯基础油的制备及其润滑性能研究

以碳酸二甲酯(DMC)和异十六醇(C_(16)H_(33)OH)为原料,甲醇钠为催化剂,采取两步反应法高效制备碳酸二异十六酯(DHC)。采用傅里叶红外光谱仪、质谱仪及核磁共振仪对反应产物进行结构表征,并初步研究其作为润滑剂基础油的热氧化安定性、理化性质及润滑性能。表征结果证明制备的产物为碳酸二异十六酯,优化条件下的收率高达90%。制备的DHC具有适宜的黏度、优异的热氧化安定性,倾点低于-60℃,且具有与癸二酸二异辛酯(DOS)相同的润滑性,适合作为高黏度指数、低温润滑剂基础油。     

润滑添加剂三乙醇胺硼酸酯的摩擦学特性研究

三乙醇胺硼酸酯是一种新的绿色水基全合成切削液防锈添加剂,但其在切削加工过程中的摩擦学特性尚未有报道。以钛合金与硬质合金为摩擦副,通过摩擦磨损试验比较三乙醇胺硼酸酯并与传统润滑添加剂丙三醇和聚乙二醇的摩擦学性能,同时考察不同含量的三乙醇胺硼酸酯水溶液的摩擦学性能。结果表明:三乙醇胺硼酸酯具有与丙三醇和聚乙二醇相似的减摩抗磨性能,在相对较高的载荷下,三乙醇胺硼酸酯的润滑性能更优;三乙醇胺硼酸酯水溶液的减摩抗磨性能随着其含量的增加逐渐增强,当三乙醇胺硼酸酯的体积分数达到40%以上时,溶液的润滑性能更为显著。研究表明,三乙醇胺硼酸酯有可能成为一种新型切削液润滑添加剂。     

微波辅助萃取-气相色谱-串联质谱法同时测定皮革制品中20种邻苯二甲酸酯含量

为了加强对皮革制品中邻苯二甲酸酯的监管,建立了气相色谱-串联质谱法同时测定皮革制品中的20种邻苯二甲酸酯。该方法以乙腈为萃取溶剂,微波萃取皮革制品中的邻苯二甲酸酯,萃取液经固相萃取柱净化后,气相色谱-串联质谱分析。在S/N=10条件下,邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二异癸酯(DIDP)和邻苯二甲酸二(4-甲基-2-戊基)酯(DMPP)的定量下限分别为0.2、0.2、0.1 mg/kg,其余邻苯二甲酸酯的定量下限均小于0.05 mg/kg,平均加标回收率为87.75%~94.59%,精密度实验RSD均小于16%。采用该方法对市售皮革制品进行测定,在2个样品中检出多种邻苯二甲酸酯。     

Theoretical explanation of the relationship between backscattered electron and x-ray linear attenuation coefficients in calcified tissues

X-ray absorption and backscattered electron (BSE) microscopies are two commonly used techniques for estimating mineral contents in calcified tissues. The resolution in BSE images is usually higher than in x-ray images, but due to the previous lack of good standards to quantify the grey levels in BSE images of bones and teeth, x-ray microtomog-raphy (XMT) images of the same specimens have been used for calibration. However, the physics of these two techniques is different: for a specimen with a given composition, the x-ray linear attenuation coefficient is proportional to density, but there is no such relation with the BSE coefficient. To understand the reason that this calibration appears to be valid, the behaviour of simulated bone samples was investigated. In this, the bone samples were modelled as having three phases: hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂), protein, and void (either empty or completely filled with polymethylmethacrylate (PMMA), a resin which is usually used for embedding bones and teeth in microscopic studies). The x-ray linear attenuation coefficients (calculated using published data) and the BSE coefficients (calculated using Monte Carlo simulation) were compared for samples of various phase proportions. It was found that the BSE coefficient correlated only with the x-ray attenuation coefficient for samples with PMMA infiltration. This was attributed to the properties of PMMA (density and mean atomic number) being very similar to those of the protein; therefore, the sample behaves like a two-phase system which allows the establishment of a monotonic relation between density and BSE coefficient. With the newly developed standards (brominated and iodinated dimethacrylate esters) for BSE microscopy of bone, grey levels can be converted to absolute BSE coefficients by linear interpolation, from which equivalent densities can be determined.     

气相色谱技术在革兰氏阳性无芽孢厌氧杆菌鉴定中的应用

使用气相色谱技术分析革兰氏阳性无芽孢厌氧杆菌的代谢产物,发现此技术在这类菌的菌属确定上有重要意义。一般来说,双歧杆菌其主要代谢产物是乙酸和乳酸,大致上比例为1.5～3:1,而乳酸杆菌属菌种其主要代谢产物是乳酸,而乙酸产量仅为乳酸的1/5～1/10左右。再通过生化性状鉴定,可进一步确定它们的菌种名称。     

甲酸分子印迹聚合物的制备及其在针式萃取技术中的应用研究

以甲酸为模板分子,4-乙烯基吡啶(4-VP)为功能单体,乙二醇二甲基丙烯酸酯为交联剂(EDMA),偶氮二异丁腈(AIBN)为引发剂,采用本体聚合法制备了具有良好选择识别性能的分子印迹聚合物.将该聚合物作为固相萃取介质,应用于新型的针式萃取技术,并结合气相色谱分析,成功用于气体中痕量甲酸的浓缩富集和测定.研究评价了各种主...     

Development of an Automated Anaerobic Biodegradability Testing Device

Abstract

The development of a low-cost device used for anaerobic biodegradability testing is described, together with its experimental validation. The equipment is based on manometric measurements of the biogas produced during the fermentation of test substances in up to seven parallel closed bioreactors. It uses separate pressure sensors and relief valves, which enable continuous measurements and avoid pressure buildup that could inhibit the biochemical reactions. A low-cost data acquisition module is used and software has been developed that is specifically suited for the end-user. The equipment has been tested and validated experimentally with a system that accounts for biohydrogen production, testing the effect of original temperature on three different pre-treated inocula, using glucose as sole source of carbon and energy. The results validate the operation of the testing equipment.     

Wear of dimethacrylate resins used in dental composites

Wear of dimethacrylate resins used as the matrix phase in dental restorative composites was characterized by two-body abrasion and singlepass sliding. Ranking of the resins was obtained by both tests. Two resins that had low values of tangential force and track width also showed relatively ductile modes of surface failure for the normal loads tested. A monomethacrylate fluorine-containing resin did not show improved wear properties by these methods of testing.     

智能型多功能温湿度测控仪的研制

本文介绍了一种智能型多功能温湿度测控仪,它综合运用了80C52单片机技术和A/D、X5045芯片,具有造价低、性能稳定、控制精度高、使用灵活、操作简便等特点。该仪器既可独立作为普通的温湿度测量仪表使用,也可单台与除湿机、空调联机使用,组成小的恒温恒湿系统;或者多台联网,配合PC机做为一套集数据采集、控制和存储为一体的高性能的温湿度控制系统使用。     

猪肉背膘中3-甲基吲哚测定方法的研究

3-甲基吲哚即粪臭素，是小肠中未消化的蛋白质在大肠厌氧微生物作用下的产物之一，对未阉割的公猪肉品质有显著的负面影响。本次实验就对猪肉背膘中3-甲基吲哚的测定方法进行了研究。结果为：标样浓度在120ng／ml范围内线性良好，回收率在97％左右，样品相对偏差在3％以下。表明该方法的灵敏度和准确度均较好。     

Analysis of fiber probes of scanning near-field optical microscope by field emission microscopy.

It is shown that field emission microscopy and related methods can be used to analyze the metal coated fiber tips, which nowadays are the most frequently used sensor for the scanning near-field optical microscopy (SNOM). Metal free and thus non field-emitting aperture for the light transmission on the tip apex can be directly seen and its parameters can be measured, which is very important for the interpretation of SNOM data.     

家用甲醛检测仪研制与应用

研制出一种采用定量采集空气样品,化学试剂盒显色,目视比色法半定量检测室内空气中甲醛仪器,从采样到报出检测结果只需17min。可用于家庭环境中甲醛是否达标的快速自测和筛选检测。     

丙烯酸酯类毛细管液相色谱整体柱的制备与评价

采用甲基丙烯酸丁酯(BMA)为功能单体,己二醇二甲基丙烯酸酯(EDMA)为交联剂,正丙醇、1,4-丁二醇和水为致孔剂,偶氮二异丁腈(AIBN)为引发剂,采用微波辐射的新方法,在毛细管内原位聚合快速制备了毛细管整体柱。扫描电镜结果表明整体材料在毛细管柱中均匀形成并与毛细管内壁结合紧密。采用自组装的毛细管液相色谱仪,优化条件下可实现了模型化合物的基线分离。与传统的热聚合和光聚合相比,微波辐射用于有机聚合基质毛细管整体柱的制备是一种更快捷、简单、有效的方法。