毛细管白酒专用柱气相色谱法测定白酒中甲醇含量

氢火焰检测器测定,外标法定量。实验结果表明,采用毛细管白酒专用色谱柱程序升温直接进样的气相色谱方法测定白酒中甲醇含量,准确度高、分离效果好、精密度高、重复性好、分析速度快。     

气相色谱法测定高纯溴化氢中的微量杂质

提出了一种溴化氢中微量气体杂质的分析方法,采用配备反吹气路的氦离子化检测器的气相色谱仪实现了高纯溴化氢中微量H₂、O₂、N₂、CO、CH₄及CO₂的分离检测。     

气相色谱法测定口服液中肌醇的含量

建立了GC法测定口服液中肌醇含量的分析方法,该方法测定肌醇的线性范围为0.05~10.0mg/mL,检出限为0.001mg/mL,相对标准偏差(n=6)为0.51%,方法回收率为98.9~102.7%,并应用于口服液中肌醇的测定,结果良好。     

气相色谱法测定口服液中肌醇的含量

建立了GC法测定口服液中肌醇含量的分析方法,该方法测定肌醇的线性范围为0.05～10.0 mg/mL,检出限为0.001 mg/mL,相对标准偏差(n=6)为0.51%,方法回收率为98.9～102.7%,并应用于口服液中肌醇的测定,结果良好.     

颅骨修复复合材料的制备

主要论述了碳纤维 (CF)和玻璃纤维 (GF)混杂增强聚甲基丙烯酸甲酯 (PMMA) /羟基磷灰石 (HA)复合材料人工颅骨的制备方法及其力学性能。通过实验 ,证实了此复合材料具有比单纯GF增强PMMA/HA复合材料人工颅骨更好的物理机械性能 ,是目前制作人工颅骨较为理想的材料。     

人工颅骨与人体颅骨的基本力学性能

本文研究了一种可适用于人体颅骨缺损修复用的纤维增强聚甲基丙烯酸甲酯复合材料。测定了该复合材料、有机玻璃材料及人体颅骨的基本力学性能。实验表明这种纤维增强 PMMA 复合材料具有优于人体颅骨和有机玻璃的物理和力学性能。     

气相色谱法测定液氧中微量乙炔

通过实验和数据说明了空分装置生产的液氧经汽化后进入配有气体纯化器、放电离子化检测器和H ayesep S 30″×1/8″填充柱的气相色谱仪,用纯化后的高纯氦作为载气,经色谱系统分离和检测,由色谱工作站采集数据并绘成色谱图,用高纯氦配制的乙炔标准气进行外标法定量,测定液氧中微量乙炔含量的方法。     

气相色谱法测定微量氧样品中含有氩气时对测定结果的影响

考察了气相色谱仪用不同气体做载气,测定微量氧样品中含有氢气时对测定结果的影响。结果表明,用氢气做载气时比用其他气体做载气时微量氧的测定结果更准确。用其他载气测定时氧气和氩气合峰。     

气相色谱法测定酱油中甜蜜素含量的探讨

本文建立了毛细管气相色谱法测定酱油中甜蜜素含量的分析方法。采用RTX-WAX毛细管色谱柱和氢火焰检测器测定,外标法定量。[结果]样品加标平均回收率为93.7%-99.3%,相对标准偏差(RSD)为2.5%-4.7%。实验结果表明,该方法简便、快速,适合酱油甜蜜素含量的测定。     

气相色谱法测定丙烯中含氧化合物

本方法采用电热金属浴加热液相丙烯,用液体对丙烯气体中的含氧化合物吸收,吸收液通过气象色谱进行测定。含氧化合物在色谱柱进行分离,FID检测器检测,外标法定量,求出丙烯中的含氧化合物。     

纳米铜/石蜡复合相变蓄热材料的导热性能研究

采用HotDisk热分析仪测试了Cu/石蜡体系在不同纳米颗粒质量分数、温度和热循环次数下的导热系数。研究表明,Cu/石蜡体系的固、液态导热系数随纳米Cu颗粒含量的增加呈非线性增加;温度变化对相变材料导热系数的影响并不明显,但当温度升高至相变温度区间时,相变材料的导热系数急剧增加;复合材料在经历100次热循环后,材料的导热系数值仍较稳定。     

Preparation of shape-stabilized phase change materials as temperature-adjusting powder

The shape-stabilized phase change materials (PCMs) composed of paraffin wax and silica were prepared in O/W emulsion with cetyl trimethylamine bromide as emulsifier and n-pentanol as assist emulsifier. The paraffin wax (with melting temperature of 29°C, crystallizing temperature of 26°C and latent heat of 142 J/g) served as latent heat storage material and the silica as supporting material, which prevented the leakage of the melted paraffin wax. Silica supporting material was formed in situ via hydrolysis and condensation from low-cost sodium silicate solution with chlorhydric acid and ammonium bicarbonate as neutralizing agent. The thermogravimetry (TG) curves show that the composite has a thermal stability superior to that of paraffin wax and that the content of paraffin wax in the composite is 65wt%. The maximum latent heat and its relevant melting point of composite are 95 J/g and 30°C, respectively.     

Modeling carbon nanotube reinforced composite materials with the cylindrical method of cells

Micromechanics modeling, utilizing a cylindrical method of cells (CMOC) model, is employed to obtain the effective mechanical properties of an elastic transversely isotropic, isothermal material system consisting of a hollow carbon nanotube (CNT) embedded in an isotropic polymeric material matrix. It is shown that weak interfacial bonding between the CNT and polymeric matrix, which is characteristic of this type of material system, can be modeled with the CMOC. Numerical solutions of the effective independent material constants are obtained, based upon appropriate values of the properties of the carbon nanotube and epoxy matrix. The numerical results are presented graphically and compared with corresponding classical closed‐form solutions. Copyright © 2015 John Wiley & Sons, Ltd.     

SnO_2/C复合材料的制备及NO_x气敏研究

为制备在室温条件下对NOx的检测具有低检测线、响应迅速、灵敏度高的材料,通过高压静电纺丝法制备了多孔SnO2/C复合材料,采用TEM、SEM、XRD等手段研究了复合材料形貌及结构.研究表明：SnO2/C复合材料表面存在丰富的微孔、介孔和大孔,且以10 nm左右的介孔居多.室温下（16～18℃）对SnO2/C复合材料NO...     

固相萃取-双柱气相色谱法测定水中多种有机磷农药残留

针对单一气相色谱柱定性分析易出现假阳性误判的情况,采用固相萃取-气相色谱双柱技术测定环境水体中多种有机磷农药的残留量。水样中的有机磷农药通过HLB固相萃取小柱富集,经洗脱浓缩后,用DB-35MS和HP-5毛细管气相色谱柱、火焰光度检测器测定。方法的平均加标回收率为86.1%～118%,相对标准偏差为3.2%～6.8%,最低检出限为20～40ng/L,可满足环境水体中痕量有机磷农药残留的分析需要。     

Characterization of electromagnetic properties of polymeric composite materials with free space method

The introduction of microwave radars during the second World War altered the air defense scenario significantly, and this led to the development of the “stealth” techniques. By reducing the detectability of aircrafts or warships, of which the radar cross section (RCS) is a measure, they could evade radar detection, which affected not only the mission success rate but also survival of them in the hostile territory. In the very early stage of the research on stealth techniques, many researches were mainly concentrated on the reduction of RCS and development of radar absorbing materials (RAM), but nowadays studies on investigating the radar absorbing structures (RAS) using fiber reinforced polymeric composite materials are becoming popular research field.

In this study, electromagnetic characteristics of unidirectional E-glass fiber reinforced epoxy composites were tested with free space methods, which can overcome drawbacks of conventional cavity and waveguide methods. Complex relative permittivities of low-loss composite were measured with respect to the angle between the fiber orientation and the electric field vector of EM wave in X-band frequency range. From the experimental data, empirical relation between the dielectric properties of composites and test variable was suggested and verified.     

聚乙二醇改性相变微胶囊制备MicroPCMs-WF/HDPE复合材料物理力学性能

以正十二烷醇（DA）为芯材,密胺树脂（MF）和聚乙二醇改性密胺（PMF）树脂为壁材制备了相变微胶囊（MicroPCMs）,并分别添加到木粉/高密度聚乙烯（WF/HDPE）复合材料中,获得了具有相变蓄热能力的MicroPCMs-WF/HDPE复合材料。采用SEM、FTIR和纳米压痕等方法对MicroPCMs的表面形态、力学性能进行了分析与表征,同时对MicroPCMs-WF/HDPE复合材料的物理力学及热性能进行了测试。结果表明:经聚乙二醇改性后,改性微胶囊（PMF-MicroPCMs）的弹性模量和硬度较未改性微胶囊（MF-MicroPCMs）分别增加了13.9%和30.0%;MicroPCMs-WF/HDPE复合材料的熔融温度区间（22.2~28.7℃）满足人体舒适温度范围,较纯WF/HDPE复合材料温度变化速率明显减缓;相比纯WF/HDPE复合材料,MicroPCMs-WF/HDPE复合材料的吸湿性、冲击强度和表面硬度增加,弯曲和拉伸性能下降;PMF-MicroPCMs-WF/HDPE复合材料的性能均优于MF-MicroPCMs-WF/HDPE复合材料,且达到了木塑装饰板材的力学性能标准要求。      

风力发电机轴承复合故障特征提取方法研究

针对较强背景噪声干扰下的风力发电机轴承复合故障特征难以准确提取的问题,提出了基于自适应最大相关峭度解卷积(AMCKD)的风力发电机轴承复合故障特征提取的方法。首先,利用人工鱼群算法(AFSA)以解卷积信号包络谱的相关峭度值为目标函数对最大相关峭度解卷积算法(MCKD)的影响参数自适应寻优;然后,将影响参数优化的MCKD对原始故障信号进行解卷积处理,对解卷积信号进行包络谱分析,通过包络谱中的主导频率成分与轴承各元件的故障特征频率相对比,准确实现轴承复合故障的诊断。仿真和工程应用实例验证了所提方法的有效性与实用性。     

Chemical composition and molecular structure of fibers from transgenic flax producing polyhydroxybutyrate,and mechanical properties and platelet aggregation of composite materials containing these fibers

In order to improve the properties of flax fibers so that they interact better with the matrix material in composites, several lines of transgenic flax were produced over-expressing the bacterial polyhydroxybutyrate (PHB) synthesis genes. Infra-red spectrophotometry revealed that the cellulose in fibers from the transgenic plants was more highly structured than in fibers from the control plants and PHB was strongly bound to the cellulose of the fibers by covalent ester and hydrogen bonds. The composite containing fibers from transgenic plants was significantly stronger and stiffer than the composites containing fibers from the control plants. Scanning electron microscopy of the fracture surface of composite sheets indicated that fibers from transgenic plants adhered to the polypropylene matrix significantly better. The composite containing fibers from transgenic plants induced almost no platelet aggregation and so may therefore be useful in the construction of biomedical devices that come in contact with blood.