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61.
A rapid test to measure performance,emission and wear of a diesel engine fueled with palm oil diesel
H. Masjuki A. M. Zaki S. M. Sapuan 《Journal of the American Oil Chemists' Society》1993,70(10):1021-1025
Results of performance, emission and tribological evaluations of palm oil methyl ester and its blends with conventional diesel
in an automobile diesel engine test bed are presented. Polymerization and carbon deposits on the fuel injector were monitored.
CO, CO2, O2, combustion efficiency and temperature of exhaust gases were also measured. Palm oil methyl ester and its blends have great
potential as alternative diesel fuel. Performance and exhaust gas emission for palm oil methyl ester and its blends with conventional
diesel are comparable with those of conventional diesel fuel. Palm oil methyl ester does not pose a severe environmental problem
and will not deteriorate engine and bearing components. 相似文献
62.
An ionic liquid, 1-butyl-3-methylimidazolium bromide, is used as reaction medium for the synthesis and crystallization of a coordination polymer, (BMIM)2[Cd3(BDC)3Br 2] (1) (BMIM = 1-butyl-3-methylimidazolium, BDC = 1,4-benzenedicarboxylate), which forms an anionic two-dimensional framework with the imidazolium cations located between the layers. This compound is thermally stable up to ca. 340 °C and exhibits blue emission in solid state at room temperature. Other characterizations by IR and UV–visible spectra are also described. 相似文献
63.
64.
Electrophoretic deposition of carbon nanotubes 总被引:1,自引:0,他引:1
Aldo R. Boccaccini Johann Cho Judith A. Roether Boris J.C. Thomas E. Jane Minay Milo S.P. Shaffer 《Carbon》2006,44(15):3149-3160
Electrophoretic deposition (EPD) has been gaining increasing interest as an economical and versatile processing technique for the production of novel coatings or films of carbon nanotubes (CNTs) on conductive substrates. The purpose of the paper is to present an up-to-date comprehensive overview of current research progress in the field of EPD of CNTs. The paper specifically reviews the preparation and characterisation of stable CNT suspensions, and the mechanism of the EPD process; it includes discussion of pure CNT coatings and CNT/nanoparticle composite films. A complete discussion of the EPD parameters is presented, including electrode materials, deposition time, electrode separation, deposition voltage and resultant electric field. The paper highlights potential applications of the resulting CNT and CNT/composite structures, in areas such as field emission devices, fuel cells, and supercapacitors. 相似文献
65.
This paper explores the use of acoustic emission (AE) and X-ray tomography to identify the mechanisms of damage and the fracture process during compressive loading on concrete specimens. Three-dimensional (3D) X-ray tomography image analysis was used to observe defects of virgin mortar specimen under different compressive loads. Cumulative AE events were used to evaluate damage process in real time according to the sand/cement ratio. This work shows that AE and X-ray tomography are complementary nondestructive methods to measure, characterise and locate damage sites in mortar. The effect of the sand proportion on damage and fracture behaviour is studied, in relation with the microstructure of the material. 相似文献
66.
Shoude Li 《International journal of systems science》2014,45(11):2390-2401
Using the well-known Arrow and Karlin (1958) dynamic production–inventory model and the model with tradable emission permits which was presented by Dobos (2005, 2007), we develop a model of the production–inventory system with deteriorating items and tradable emission permits. The objective of this paper is to apply the optimal control theory to solve the production–inventory problem with deteriorating items and tradable emission permits, and derive the optimal inventory level and the optimal production rate that minimise the total cost. The results are discussed with a numerical example and a sensitivity analysis of the optimal solution with respect to the parameters of the production–inventory system is carried out. 相似文献
67.
The paper presents a theoretical analysis of stresses generated during convective drying of kaolin, based on elastic and viscoelastic models. The equations of these models were solved analytically for a cylindrically shaped sample; the distribution and evolution of the radial and circumferential stresses are illustrated in diagrams. The acoustic emission method was used in experimental tests for identification on line of the time period during which the stresses reach their maximal values. A better correlation has been found between the experimental tests and the theoretical predictions obtained on the basis of the viscoelastic model. 相似文献
68.
以氮化硅细粉(粒度<0.088 mm,w(β-Si3N4)>95%)、碳化硅(w(SiC)>98%,粒度分别为2.8~0.9mm、0.9~0.15 mm、<0.115 mm和<0.063 mm四级)、硅粉(粒度<0.045 mm,w(Si)>98%)和硅灰(w(SiO2)=98.3%)为原料,以木质素磺酸钙水溶液作成型结合剂,采用150 MPa的压力成型为65 mm×114 mm×230mm的Si3N4-SiC、Si3N4-SiC-Si和Si3N4-SiC-SiO2三种试样.在空气气氛中,以50℃·h-1的升温速度升至800℃保温4 h,再升至1450℃保温2 h,自然冷却至室温后,测定烧成后试样的常温耐压强度、常温抗折强度、1400℃下的高温抗折强度、显气孔率、体积密度和残氮率,并采用XRD、SEM和EPMA等手段分析烧后试样的相组成和显微结构.结果表明3种试样在空气气氛中烧成后的高温(1400℃)和常温抗折强度都比较高,显气孔率都比较低,而耐压强度则以Si3N4-SiC试样的最高;烧成后试样中心区域的残氮率以Si3N4-SiC-Si试样的最高,Si3N4-SiC-SiO2试样的次之,Si3N4-SiC试样的最小;在空气气氛中烧成后,Si3N4-SiC试样中的Si3N4分解较多,SiC-Si3 N4-Si试样的表面和内部都明显含有单质Si,SiC-Si3N4-SiO2试样表面区域的Si2N2O晶体发育很好,而内部区域的晶体发育较小. 相似文献
69.
70.
Retardation of volatile aldehyde formation in the exhaust of frying oil by heating under low oxygen atmospheres 总被引:2,自引:0,他引:2
Mariko?Fujisaki Yasushi?Endo Kenshiro?FujimotoEmail author 《Journal of the American Oil Chemists' Society》2002,79(9):909-914
Volatile aldehydes were generated in the exhaust of high-oleic safflower oil during heating at 180°C by spraying water into
atmospheres with four levels of oxygen concentrations (2, 4, 10, and 20%). These aldehydes were quantitatively analyzed by
HPLC after the conversion to 2,4-dinitrophenyl hydrazones. Ten alkanals (C2 through C10), eight 2-alkenals (C3 through C10) and three 2,4-alkadienals (C7, C9, and C10) were found. These aldehyde levels were found to be positively correlated with both the heating time and the atmospheric
oxygen concentration. The total amounts of aldehydes were the lowest in the oil heated in an atmosphere with 2% O2, and corresponded to 1/10 of those in the atmosphere with 20% O2. Acrolein was not found in oils heated in the atmosphere with 2% oxygen. These results suggest that frying in atmospheres
with low oxygen levels can effectively decrease the generation of volatile aldehydes in the exhaust. 相似文献