全文获取类型
收费全文 | 104篇 |
免费 | 3篇 |
专业分类
化学工业 | 37篇 |
金属工艺 | 1篇 |
能源动力 | 14篇 |
轻工业 | 40篇 |
无线电 | 1篇 |
一般工业技术 | 8篇 |
自动化技术 | 6篇 |
出版年
2021年 | 4篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 7篇 |
2013年 | 8篇 |
2012年 | 16篇 |
2011年 | 23篇 |
2010年 | 8篇 |
2009年 | 10篇 |
2008年 | 5篇 |
2007年 | 2篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1995年 | 1篇 |
排序方式: 共有107条查询结果,搜索用时 290 毫秒
1.
On the effect of geometrical designs and failure modes in composite axial crushing: A literature review 总被引:1,自引:0,他引:1
Composite materials have been known for its low density, ease in fabrication, high structural rigidity, and wide range applications, i.e. aeronautic applications and automotive industry. Due to this, extensive studies had been conducted to evaluate its axial crushing ability to replace metallic materials. In this paper, it reviewed the usage of fibre reinforced plastic composite (FRP) as an energy absorption application device. Failure modes and geometrical designs such as shapes, geometry and triggering effect have been studied where these factors affected on peak load and specific energy absorption significantly. Accordingly, numerical analysis for axial crushing of affected factors had been simulated to predict the failure mechanisms of FRP composites. 相似文献
2.
Nurazni Amat Bahari Wan Nor Roslam Wan Isahak Mohd Shahbudin Masdar Zahira Yaakob 《国际能源研究杂志》2019,43(10):5128-5150
Hydrogen becomes one of the most clean energy sources. The major issues on hydrogen are lack of practical clean and high‐temperature processes and possible practical storage of clean hydrogen. An energy intensive of clean hydrogen storage via chemical and liquid fuel production route is the current demand. This article reviewed the most recent research for hydrogen (H2) production by using several methods, such as thermochemical process, thermal decomposition, biological approaches, electrolysis, and photocatalytic method. H2 storage types, including physical and chemical approaches, were also reviewed. The produced H2 was stored as valuable chemicals and fuels via CO2 hydrogenation reaction. Reactor designs are the illustrated number of design ranging from the fixed bed to the continuous stirred tank reactor. Catalyst type, catalytic system, and the related mechanism of CO2 hydrogenation reaction to form alcohol, alkanes, and carboxylic acid were also discussed in detail. 相似文献
3.
Wai-Fun Leong Kok-Whey Cheong Oi-Ming Lai Kamariah Long Yaakob B. Che Man Misni Misran Chin-Ping Tan 《Journal of the American Oil Chemists' Society》2011,88(5):717-725
The purpose of this study was to optimize the production parameters for water-soluble phytosterol nanodispersions. Response
surface methodology (RSM) was employed to model and optimize three of the processing parameters: mixing time (t) by conventional homogenizer (1–20 min), mixing speed (v) by conventional homogenizer (1,000–9,000 rpm) and homogenization pressure (P) by high-pressure homogenizer (0.1–80 MPa). All responses [i.e., mean particle size (PS), polydispersity index (PDI) and
phytosterols concentration (Phyto, mg/l)] fitted well to a reduced quadratic model by multiple regressions after manual elimination.
For PS, PDI and Phyto, the coefficients of determination (R
2) were 0.9902, 0.9065 and 0.8878, respectively. The optimized processing parameters were 15.25 min mixing time, 7,000 rpm
mixing speed and homogenization pressure 42.4 MPa. In the produced nanodispersions, the corresponding responses for the optimized
preparation conditions were a PS of 52 nm, PDI of 0.3390 and a Phyto of 336 mg/l. 相似文献
4.
Application of FTIR Spectroscopy for the Determination of Virgin Coconut Oil in Binary Mixtures with Olive Oil and Palm Oil 总被引:1,自引:0,他引:1
Abdul Rohman Yaakob B. Che Man Amin Ismail Puziah Hashim 《Journal of the American Oil Chemists' Society》2010,87(6):601-606
Rapid Fourier transform infrared (FTIR) spectroscopy combined with attenuated total reflectance (ATR) was applied for quantitative
analysis of virgin coconut oil (VCO) in binary mixtures with olive oil (OO) and palm oil (PO). The spectral bands correlated
with VCO, OO, PO; blends of VCO and OO; VCO and PO were scanned, interpreted, and identified. Two multivariate calibration
methods, partial least square (PLS) and principal component regression (PCR), were used to construct the calibration models
that correlate between actual and FTIR-predicted values of VCO contents in the mixtures at the FTIR spectral frequencies of
1,120–1,105 and 965–960 cm−1. The calibration models obtained were cross validated using the “leave one out” method. PLS at these frequencies showed the
best calibration model, in terms of the highest coefficient of determination (R
2) and the lowest of root mean standard error of calibration (RMSEC) with R
2 = 0.9992 and RMSEC = 0.756, respectively, for VCO in mixture with OO. Meanwhile, the R
2 and RMSEC values obtained for VCO in mixture with PO were 0.9996 and 0.494, respectively. In general, FTIR spectroscopy serves
as a suitable technique for determination of VCO in mixture with the other oils. 相似文献
5.
6.
Deborah J Ossip-Klein Susan Fisher Sergio Diaz Zahira Qui?ones Essie Sierra Ann Dozier Scott McIntosh Joseph Guido Paul Winters Omar Diaz LaToya Armstrong 《Nicotine & tobacco research》2008,10(5):851-860
The Dominican Republic is a tobacco-growing country, and tobacco control efforts there have been virtually nonexistent. This study provides a first systematic surveillance of tobacco use in six economically disadvantaged Dominican Republic communities (two small urban, two peri-urban, two rural; half were tobacco growing). Approximately 175 households were randomly selected in each community (total N = 1,048), and an adult household member reported on household demographics and resources (e.g., electricity), tobacco use and health conditions of household members, and household policies on tobacco use. Poverty and unemployment were high in all communities, and significant gaps in access to basic resources such as electricity, running water, telephones/cell phones, and secondary education were present. Exposure to tobacco smoke was high, with 38.4% of households reporting at least one tobacco user, and 75.5% allowing smoking in the home. Overall, 22.5% reported using tobacco, with commercial cigarettes (58.0%) or self-rolled cigarettes (20.1%) the most commonly used types. Considerable variability in prevalence and type of use was found across communities. Overall, tobacco use was higher in males, illiterate groups, those aged 45 or older, rural dwellers, and tobacco-growing communities. Based on reported health conditions, tobacco attributable risks, and World Health Organization mortality data, it is estimated that at least 2,254 lives could potentially be saved each year in the Dominican Republic with tobacco cessation. Although it is expected that the reported prevalence of tobacco use and health conditions represent underestimates, these figures provide a starting point for understanding tobacco use and its prevalence in the Dominican Republic. 相似文献
7.
Camilla Chua Soo Leng Badlishah Sham Baharin Yaakob Che Man Chin Ping Tan 《Journal of the science of food and agriculture》2008,88(9):1512-1517
BACKGROUND: Squalene was concentrated from palm fatty acid distillate (PFAD) in this study using commercial immobilised Candida antarctica lipase (Novozyme 435®). The PFAD was neutralised (NPFAD) using an alkali to liberate the free fatty acids and then hydrolysed at 65 ± 1 °C. The enzymatic hydrolysis on NPFAD was optimised using response surface methodology (RSM) before being neutralised again to obtain a concentrated squalene fraction. RESULTS: A five‐level, three‐factor central composite rotatable design was adopted to evaluate the effects of the enzymatic hydrolysis parameters reaction time (4–12 h), water content (50–70% w/w) and enzyme concentration (1.5–3.5% w/w) on the percentage yield of squalene concentration. The optimal reaction parameters for maximum yield of squalene concentration were identified from the respective contour plots. The optimal enzymatic hydrolysis conditions were a reaction time of 7.05 h, a water content of 61.40% w/w and an enzyme concentration of 2.23% w/w. CONCLUSION: RSM was used to determine the optimal conditions for enzymatic hydrolysis of NPFAD with C. antarctica lipase for maximum recovery of squalene which could be implemented on an industrial scale. Copyright © 2008 Society of Chemical Industry 相似文献
8.
Potential Use of FTIR-ATR Spectroscopic Method for Determination of Virgin Coconut Oil and Extra Virgin Olive Oil in Ternary Mixture Systems 总被引:1,自引:0,他引:1
The aim of this study was to investigate the feasibility of Fourier-transform infrared (FTIR) spectroscopy combined with multivariate
calibrations of partial least square (PLS) and principle component regression (PCR) for analysis of virgin coconut oil (VCO)
in the ternary mixture with palm oil (PO) and olive oil, and for analysis of extra virgin olive oil (EVOO) mixed with soybean
oil (SO) and corn oil (CO). The spectra of individual oils and their blends with certain concentrations were scanned using
horizontal attenuated total reflectance accessory at mid-infrared region of 4,000–650 cm−1. The optimal frequency regions selected for calibration models were based on its ability to give the highest values of coefficient
of determination (R
2) and the lowest values of root mean standard error of calibration (RMSEC). PLS was slightly better for quantitative analysis
of VCO and EVOO compared with PCR. VCO in ternary mixtures is successfully determined at frequency region of 1,200–1,000 using
second derivative FTIR spectra with R
2 and RMSEC values of 0.999 and 0.200, respectively. Meanwhile, EVOO is best determined at 1,200–1,000 using first derivative
FTIR spectra with R
2 and RMSEC values of 0.999 and 0.975, respectively. The results showed that FTIR spectroscopy offers accurate and reliable
technique for quantitative analysis of VCO and EVOO in ternary systems. In addition, the developed method can be used for
the monitoring of VCO and EVOO adulteration with cheaper oils like PO in VCO as well as SO and CO in EVOO. 相似文献
9.
Wai-Fun Leong Oi-Ming Lai Kamariah Long Yaakob B. Che Man Misni Misran Chin-Ping Tan 《Food chemistry》2011
The purpose of this study was to prepare and characterise water-soluble phytosterol nanodispersions for food formulation. The effects of several factors were examined: four different types of organic phases (hexane, isopropyl alcohol, ethanol and acetone), the organic to aqueous phase ratio and conventional homogenisation vs. high-pressure homogenisation. We demonstrated the feasibility of phytosterol nanodispersions production using an emulsification–evaporation technique. The results showed that hexane was able to produce the smallest particle size at a mean diameter of approximately 50 nm at monomodal distribution. Phytosterol nanodispersions prepared with a higher homogenisation pressure and a higher organic to aqueous phase ratio resulted in significantly larger phytosterol nanoparticles (P < 0.05). Phytosterol loss after high-pressure homogenisation ranged from 3% to 28%, and losses increased with increasing homogenisation pressure. Elimination of the organic phase by evaporation resulted in a phytosterol loss of 0.5–9%. 相似文献
10.
Samaneh Shahgaldi Zahira Yaakob Dariush Jafar Khadem Wan Ramli Wan Daud 《International Journal of Hydrogen Energy》2012
In the present work, titania-coated (TiO2) boron nitride nanofibers were produced by the electrospinning method, and the effect of heat treatment on the nanofibers was studied. Electrospinning method is often adopted for the synthesis of one-dimensional nanofibers due to high productivity, simplicity, and cost-effectiveness. In this study, boric oxide was deposited on co-electrospun polyacrylonitrile and TiO2. TiO2-coated boron nitride nanofibers, with a diameter of 100 nm, were obtained after heat treatment and nitridation. The effects of heat treatment on the morphology, surface area and hydrogen storage capacity were studied extensively. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) showed long, bead-free nanofibers and the presence of TiO2 nanoparticles on the nanofibers. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy depicted hexagonal structures of boron nitride. The hydrogen uptake capacities of the nanofibers were investigated by pressure composition isotherm (PCI) in the pressure range of 1–70 bar at room temperature. 相似文献