柴油车碳烟微粒过滤器的研制

本文简述了一种实用新型碳烟微粒过滤技术,并且以485Q型柴油机为对象,针对130型二吨载货车配套研制了泡沫陶瓷过滤器。     

Studies of Diesel Engine Particle Emissions During Transient Operations Using an Engine Exhaust Particle Sizer

Diesel engine particle emissions during transient operations, including emissions during FTP transient cycles and during active regenerations of a NOx adsorber, were studied using a fast Engine Exhaust Particle Sizer (EEPS). For both fuels tested, a No. 2 certification diesel and a low sulfur diesel (BP-15), high particle concentrations and emission rates were mainly associated with heavy engine acceleration, high speed, and high torque during transient cycles. Averaged over the FTP transient cycle, the particle number concentration during tests with the certification fuel was 1.2e8/cm³, about four times the particle number concentration observed during tests using the BP-15 fuel. The effect of each engine parameter on particle emissions was studied. During tests using BP-15, the particle number emission rate was mainly controlled by the engine speed and torque, whereas for Certification fuel, the engine acceleration also had a strong effect on number emission rates. The effects of active regenerations of a diesel NOx adsorber on particle emissions were also characterized for two catalyst regeneration strategies: Delayed Extended Main (DEM) and Post 80 injection (Post80). Particle volume concentrations observed during DEM regenerations were much higher than those during Post80 regenerations, and the minimum air to fuel ratio achieved during the regenerations had little effect on particle emission for both strategies. This study provides valuable information for developing strategies that minimize the particle formation during active regenerations of NOx adsorbers.     

RIM工艺中的注射压力效应

探讨了注射压力变化引起的ＲＩＭ工艺中的各种效应。提出了确定注射压力应考虑的事项。     

原油性质对柴油生产的影响

我国已开始取代美国成为世界第一大原油进口国,炼化企业多数都在掺炼或全部炼制进口原油。为取得良好的经济效益,炼化企业多选择价低质劣的原油进行加工,随之而来的是产品质量受到极大困扰。针对燃料型炼油企业出现的因原油性质变化引起柴油性质不稳定的情况,通过长时间的摸索和分析,找出环烷基对柴油燃烧性指标的影响关系,为企业生产合格产品及优化原油配比提供指导。     

柴油性能对车用发动机的影响

柴油是柴油机的主要燃料,其使用性能和技术指标的控制对发动机正常工作有着深远的影响。文章简要介绍了发动机的工作原理,综述了柴油的物理化学性质对发动机的影响。     

Filter Material Effects on Particle Absorption Optical Properties

Absorption enhancement and shadowing effects were investigated for nigrosin-laden quartz (fibrous), Teflon (matted), and polycarbonate (membrane) filters in inert surroundings at different sample steady-state temperatures and particle mass loadings. Sample absorptivity was determined using a novel laser-heating technique, which is based on perturbing the sample steady-state temperature and monitoring the thermal response during decay back to steady state, along with a model for thermal energy conservation. In addition, transmissivity measurements were carried out to enable determination of the sample absorption coefficient. The results indicated that the isolated-nigrosin absorption coefficient decreased with steady-state temperature and increased with mass loading and filter pore size. Comparing the absorption coefficient for both the isolated nigrosin and nigrosin-laden filters, indicated that absorption enhancement was most significant for the Teflon filters and least significant for the polycarbonate filters. The effect became more significant as the pore size decreased, steady-state temperature increased, and particle mass loading decreased. The decrease in the isolated-nigrosin, mass-specific absorption cross-section with heavier sample loadings was attributed to shadowing effects.

Copyright 2014 American Association for Aerosol Research     

橡胶粒子尺寸对ABS树脂性能的影响

通过乳液聚合制备了橡胶粒子尺寸为64～420 nm的丙烯腈-丁二烯-苯乙烯(ABS)共聚物.然后将其与SAN-T树脂熔融共混制备橡胶质量分数为15%的ABS树脂.研究了橡胶粒子尺寸对ABS树脂力学性能影响和材料内部形态结构.结果表明:随着橡胶粒子尺寸的增加ABS树脂的冲击韧性提高.当橡胶粒子尺寸在320 nm时,拉伸强度达到最大,ABS树脂的综合性能达到最好.粒子尺寸在64～110 nm时,橡胶粒子在基体内部发生团聚,材料发生脆性断裂.当橡胶粒子尺寸在216～420 nm时,材料主要以韧性断裂为主,发生脆韧转变.具有双峰分布ABS-110nm/ABS-275 nm共混物大、小橡胶粒子间发生明显的协同作用.     

生物柴油掺烧甲醇对柴油机污染物影响研究

在186FA柴油机上,进行了燃用生物柴油和甲醇/生物柴油混合燃料的排放试验。研究结果表明,与燃用生物柴油相比,BM15在Pe=1.57 kW时CO升高279.1%,HC排放升高96.3%;随着混合燃料中甲醇浓度增加,NOx排放减少,标定转速满负荷BM15的NOx排放降低42.7%;低负荷时排气烟度相差不大,均不超过0.1 BSU,高负荷时BM15排气烟度降低51.2%。     

非离子表面活性剂缔合结构的物理化学性能研究进展

从浊点,表面张力表面吸附、胶束形成热力上行为、与离子表面活性剂的复配,与聚合物的相互作用,微乳液的热力学性质,在非水体系中的物化性能等方面总结了近年来国内外应用现代实验技术对非离子表面活性剂缔合结构物理化学性能的研究现状况,得到了许多有益的规律和结论,并对各个研究领域进行了展望。这地丰富表面活性剂的基础理论和进一步开发利用非离子表面活性剂具有重要意义。     

Effect of Crystal Size on Physico-Chemical Properties of ZSM-5

In an attempt to produce a ZSM-5 type material with ample mesoporosity as well as micro porosity and improved external surface area, the nanocrystalline ZSM-5 (NZ) was synthesized. The material NZ was characterized by a variety of physical techniques and its properties were compared with that of micrometer range ZSM-5 (HZ). Improvement in pore volume along with mesoporosity is observed in NZ. Though there is an improvement in micropore volume, the mesopores with diameter > 100 Å have mainly contributed to the improved pore volume in NZ. The organic template used in NZ synthesis decomposed at two different temperatures in DTA/TGA studies suggesting the additional role of template in mesopore formation in NZ. The NZ exhibited relatively lower acidity, but has greater amount of strong acidity when compared to HZ.     

Physico-Chemical Properties of the Egyptian Tamarind Seed Oil

The physico-chemical properties of the Egyptian Tamarind seed oil were investigated. The seeds were found to contain a fair amount of oil (16.25%). It was found that the oil has a high acid and iodine values in comparison with cotton seed oil. Arachidic, linoleic, oleic, stearic, palmitic, myristic, and lauric were fractionated by gas liquid chromatography from the tamarind seed oil. More than 50% of the total acids are unsaturated. The infrared spectroscopy showed the presence of 7 absorption bands at wave-number cm^?1 (730, 1150, 1380, 1480, 1750, 2900 and 2950) in the investigated oil. On the other hand chemical analysis of the cake showed a lower protein content and higher sugar content.     

脉动注射对模腔压力的影响

介绍了立式液压振动注射机的工作原理.在立式液压振动注射机上进行传统注射成型及动态注射成型,制取低密度聚乙烯(LDPE)圆盘试样,利用自制的压力传感器及数据采集系统对模腔压力进行实时采集.实验结果表明,传统注射成型与动态注射成型的模腔压力随时间的变化趋势基本相同;模腔压力波动频率与柱塞杆振动频率相同;随着柱塞杆振动频率、振幅的增大,模腔压力的波动幅度增大,平均模腔压力增大,最大模腔压力也增大.     

Effect of Waste Cooking Oil Biodiesel on the Properties of Particulate from a DI Diesel Engine

The present work focuses on the effect of waste cooking oil biodiesel on the particulate mass, number concentration, nanostructure, and oxidative reactivity under different engine speeds and engine loads. Particulate samples were collected from the diluted exhaust of a medium-duty direct injection diesel engine and were used to analyze the physico-chemical properties via the transmission electron microscope (TEM) and the thermogravimetric analyzer/differential scanning calorimeter (TGA/DSC). The TEM images reveal that smaller primary particles are formed at higher engine speed, lower engine load, or using biodiesel. Quantitative analysis of the nanostructures indicates more soot with more disordered configuration, in which shorter and more curved graphene layer is prevailing at lower engine load or when using biodiesel. Furthermore, the TGA results infer that the soot oxidative reactivity is closely related to the nanostructure properties and the effect of engine load is more pronounced than the effect of engine speed. Also biodiesel soot has faster oxidative reactivity than diesel soot. Moreover, results obtained for B30 (30% biodiesel and 70% diesel fuel) lie in between those for biodiesel and diesel fuel.

Copyright 2015 American Association for Aerosol Research     

Effects of Aluminum Particle Size on the Detonation Pressure of TNT/Al

To better understand the influence of the aluminum particle size on the detonation pressure of TNT/Al, electrical conductivity experiment and detonation pressure experiment were performed in this study. Four types of TNT/Al were considered, in which the particle size of aluminum was 50 nm, 100 nm, 1.50 μm, and 9.79 μm, respectively. The combustion process of Al in TNT/Al was detected by electrical conductivity experiment, and the detonation pressures of TNT/Al were measured by using the manganin pressure sensors. According to the experimental results, the Chapman Jouguet (CJ) pressure of the explosive containing nano‐sized aluminum is higher than the explosive containing micron‐sized aluminum powder because of the combustion of nano‐sized aluminum in the detonation reaction zone. In addition, a smaller aluminum particle size in TNT/Al is associated with a slower detonation pressure attenuation. This study gives a clearer picture of how aluminum particle size contributes to detonation pressure on timescales from 0 to 0.82 μs.     

烷基多苷物化性能的研究

对不同烷链长度的烷基多苷的表面张力等物化性能进行了评价 ,发现短烷链的APG有丰富的泡沫和优良的润湿力 ,而长烷链烷基多苷具有优良的降低表面张力能力和乳化力。烷基多苷与脂肪醇醚硫酸盐和甜菜碱复配物的性能测定表明 ,除乳化力外 ,烷基多苷与脂肪醇醚硫酸盐的复配物都显示了一定的协同增效作用。烷基多苷与甜菜碱复配物在所测定的性能中都显示了协同增效作用。     

Effect of Functionalization of Lignocellulosic Fibers on Their Physico-Chemical and Thermal Properties

In this paper Agave fiber has been functionalized through graft copolymerization and physico-chemical and thermal properties have been investigated. The graft copolymerization of methyl methacrylate and acrylonitrile onto Agave americana fibers was carried out under pressure using ceric ammonium nitrate as redox initiator. The chemical resistance studies were carried out in hydrochloric acid and sodium hydroxide. Water absorption studies were also carried out by exposing grafted fibers to accelerated weathering under different humidity levels ranging from 40 to 95%. Characterization of functionalized fibers was done through Fourier Transform Infra Red spectroscopy, scanning electron microscopy, and X-ray diffraction techniques.     

有机磷酸盐成核剂粒径对PP性能的影响

通过调控反溶剂法中的转速、反溶剂与溶剂配比、溶液浓度等条件制备了不同粒径的2,2’–亚甲基双(4,6–二叔丁基苯基)磷酸钠(NA–40)成核剂,考察了NA–40粒径对等规聚丙烯(i PP)力学性能的影响,并利用差示扫描量热(DSC)仪研究了NA–40粒径对i PP结晶性能的影响。结果表明,随着NA–40粒径的增加,NA–40对i PP力学性能的改善作用变弱。NA–40平均粒径为(17.7±2.2)μm时,i PP/NA–40–1的弯曲弹性模量、弯曲强度和拉伸强度与纯i PP相比,分别提高了44.5%,20.5%和8.3%,相应的缺口冲击强度有所降低;当NA–40平均粒径为(52.6±1.1)μm时,i PP/NA–40–4的弯曲弹性模量、弯曲强度和拉伸强度的增幅分别降至16.8%,2.3%和6.4%。在较低的降温速率下,NA–40粒径对结晶峰值温度(Tc)的影响不明显,提高降温速率对Tc的影响开始显现。用扫描电子显微镜观察NA–40形貌发现,NA–40呈棒状,加工过程影响NA–40粒径,但对NA–40形貌没有影响。利用偏光显微镜观察NA–40在i PP熔体中的分散性,粒径较小的NA–40能够均匀分散在i PP熔体中,而粒径较大的分散性差,大大降低了NA–40的有效成核浓度,影响了NA–40对i PP力学性能及结晶性能的改善作用。     

Effect of Solvent on Physico-Chemical Properties and Antibacterial Activity of Chitosan Membranes

Chitosan is widely used in various applications such as pharmaceutical, medical, wastewater treatment (WWTR), and antibacterial. Modifying chitosan's properties is still attractive in scientific and industrial research. The acid solvation effect on the antibacterial activity (ABA) and physico-chemical properties of chitosan membranes synthesized via the solution casting-solvent evaporation technique was investigated. Various acids such as acetic, ascorbic, citric, glycolic, maleic, oxalic, and tartaric acid were used as chitosan solvents and membrane properties were characterized by Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) in order to study chemical interaction between the acid solvent and the shift of carbonyl and amine groups. Thermogravimetric analysis (TGA), static swelling, membrane thickness, and tensile strength experiments also characterized the membranes’ physical, chemical, and thermal properties. Further, the effect of acid solvation on the ABA of chitosan membranes for WWTR was interrogated with Escherichia coli and acetic acid solvated chitosan membrane exhibited highest ABA (99%).     

乳化剂体系对乳液压敏胶粘剂性能的影响

利用三种不同的乳化剂体系合成丙烯酸酯乳液压敏胶粘剂,研究了乳化剂体系对产物分子量,分子量分布以及对压敏胶各项性能的影响。结果表明,用阴离子乳化剂Ⅰ制得的乳液具有较高的平均分子量,持粘性好,但乳液的稳定性较差,而用复合乳化剂Ⅲ制备的乳液的平均分子量较低,持粘性差,但乳液的稳定性好,用复合乳化剂Ⅱ制备的乳液具有较好的综合性能。     

PP／PE-HD共混体系在压力振动注射成型中的形态与性能研究

探讨了采用自行研制的压力振动注射成型装置对加工聚丙烯（PP）/高密度聚乙烯（PE—H19）共混物的影响。结果表明：两相相容性得到一定改善，试样的力学性能得到了大幅度的提高，其中PP／PE—HD（60／40）组分的冲击强度相对于普通注射提高了约294％。示差扫描量热测试表明振动注射会使PP和PE—HD具有部分的相容性，且样品结晶度比常规注射的高。广角X射线衍射分析表明振动注射成型有利于y晶的生成，从而试样的模量及强度得到提高。扫描电镜测试表明采用振动注射成型后，PE—HD分散相的尺寸明显变小而且分布更加均匀，实现了两组分之间的微区分离。