全文获取类型
收费全文 | 208篇 |
免费 | 13篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 75篇 |
金属工艺 | 1篇 |
机械仪表 | 7篇 |
建筑科学 | 6篇 |
能源动力 | 9篇 |
轻工业 | 15篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 43篇 |
一般工业技术 | 29篇 |
冶金工业 | 8篇 |
自动化技术 | 25篇 |
出版年
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 8篇 |
2013年 | 21篇 |
2012年 | 5篇 |
2011年 | 15篇 |
2010年 | 8篇 |
2009年 | 17篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 12篇 |
2005年 | 8篇 |
2004年 | 13篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 7篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有222条查询结果,搜索用时 31 毫秒
1.
The application of supercritical fluid chromatography (SFC) coupled with a UV variable-wavelength detector to isolate the
minor components (carotenes, vitamin E, sterols, and squalene) in crude palm oil (CPO) and the residual oil from palm-pressed
fiber is reported. SFC is a good technique for the isolation and analysis of these compounds from the sources mentioned. The
carotenes, vitamin E, sterols, and squalene were isolated in less than 20 min. The individual vitamin E isomers present in
palm oil were also isolated into their respective components, α-tocopherol, α-tocotrienol, γ-tocopherol, γ-tocotrienol, and
δ-tocotrienol. Calibration of all the minor components of palm as well as the individual components of palm vitamin E was
carried out and was found to be comparable to those analyzed by other established analytical methods. 相似文献
2.
Sit-Foon?Cheng Yuen-May?ChooEmail author Ah-Ngan?Ma Cheng-Hock?Chuah 《Journal of the American Oil Chemists' Society》2005,82(11):791-795
Rapid synthesis of high-purity MAG from refined, bleached, and deodorized palm stearin (RBDPS) via chemical glycerolysis in the presence of pyridine was developed to obviate the conventional molecular distillation in the
production of pure MAG. The optimal reaction for the sodium methoxide-catalyzed glycerolyis of RBDPS was recorded at 110°C
using a 3 wt% catalyst concentration based on the weight of RBDPS, with an RBDPS/glycerol ratio of 1∶2 and an RBDPS/pyridine
ratio of 1∶4. High yields of over 99% were achieved rapidly in 15 min, and increases in DAG and FFA were observed after a
prolonged reaction time. 相似文献
3.
Guanyao Huang Ashwin Lall Chen-Nee Chuah Jun Xu 《Journal of Network and Systems Management》2011,19(1):84-110
Discovering icebergs in distributed streams of data is an important problem for a number of applications in networking and
databases. While previous work has concentrated on measuring these icebergs in the non-distributed streaming case or in the
non-streaming distributed case, we present a general framework that allows for distributed processing across multiple streams
of data. We compare several of the state-of-the-art streaming algorithms for estimating local elephants in the individual
streams. However, since an iceberg may be hidden by being distributed across many different streams, we add a sampling component
to handle such cases. We provide a novel taxonomy of current sketches and perform a thorough analysis of the strengths and
weaknesses of each scheme under various QoS metrics, using both real and synthetic Internet trace data. We summarize their
performance and discuss the implications for the future design of sketches. 相似文献
4.
Effect of Multi-Wall Carbon Nanotubes on the Mechanical Properties of Natural Rubber 总被引:1,自引:0,他引:1
Muataz Ali Atieh Nazlia Girun El-Sadig Mahdi Hairani Tahir Chuah Teong Guan Maan Fahmi Alkhatib Fakhru'l-Razi Ahmadun Dayang Radia Baik 《Fullerenes, Nanotubes and Carbon Nanostructures》2006,14(4):641-649
Multi-walled carbon nanotubes (MWNTs) were used to prepare natural rubber (NR) nanocomposites. Our first efforts to achieve nanostructures in MWNTs/NR nanocomposites were formed by incorporating carbon nanotubes in a polymer solution and subsequently evaporating the solvent. Using this technique, nanotubes can be dispersed homogeneously in the NR matrix in an attempt to increase the mechanical properties of these nanocomposites. The properties of the nanocomposites such as tensile strength, tensile modulus, elongation at break and hardness were studied. Mechanical test results show an increase in the initial modulus for up to 12 times in relation to pure NR. In addition to mechanical testing, the dispersion state of the MWNTs into NR studied by Transmission Electron Microscopy (TEM) in order to understand the morphology of the resulting system 相似文献
5.
In this paper, we propose to use the autoregressive (AR)-based interpolator with Wiener filter and apply the idea to scanning electron microscope (SEM) images. The concept for combining the AR-based interpolator with Wiener filtering comes from the essential requirement of Wiener filtering for accurate and consistent estimation of the power of the noise in images prior to filter implementation. The resultant filter is called AR-Wiener filter. The proposed filter is embedded onto the frame grabber card of the scanning electron microscope (SEM) for real-time image processing. Different images are captured using SEM and used to compare the performances of the conventional Wiener and the proposed AR-Wiener technique. 相似文献
6.
Image interpolation is one of the key technologies in image/video processing. In this study, a new adaptive image interpolation algorithm is proposed. The objective of the proposed approach is to recover up-sampled image frames from the corresponding decimated (low-resolution) image frames. In the proposed approach, within each iteration, two proposed nonlinear filters are utilized to iteratively generate high-frequency components lost within the decimation procedure. Finally, a post-processing procedure is adopted to reduce the blocking artifacts within the interpolated images. Based on the experimental results obtained in this study, in terms of the average PSNRp (peak signal-to-noise ratio) in dB and subjective measure of the quality of the interpolated images, the interpolation results by the proposed approach are better than that by three existing interpolation approaches for comparison. 相似文献
7.
8.
Chien Hwa Chong Chung Lim Law Michael Cloke Luqman Chuah Abdullah Wan Ramli Wan Daud 《Drying Technology》2013,31(10):1286-1293
Sun drying of chempedak (Artocarpus integer) was carried out on different sample sizes to investigate the effects on product quality. Fick's second law model was used to determine the effective diffusivities of sun–dried chempedak slabs based on the drying rate versus moisture content plots. In addition, texture degradation and total color changes were investigated. The texture and color changes of dried chempedak were relatively significant (p < 0.05) compared to fresh chempedak. There was an increase in dried fruit hardness and chewiness but a decrease in springiness and cohesiveness during drying. 相似文献
9.
C. S. Lee T. L. Ooi C. H. Chuah S. Ahmad 《Journal of the American Oil Chemists' Society》2007,84(12):1161-1167
A new type of rigid polyurethane foam was produced by incorporating oxazolidone heterocyclic rings on to polyurethane backbones.
Epoxidized diethanolamides were synthesized by reacting palm oil blends of epoxidized palm olein and refined bleached deodorized
palm kernel olein with diethanolamine to produce rigid polyurethane foams. Epoxides, retained in the diethanolamides, reacted
with isocyanate during foam production in the presence of AlCl3–THF complex catalyst to form oxazolidone linkages in the polyurethane network. The carbonyl stretch of oxazolidone was identified
at 1,750 cm−1 through Fourier Transform Infra Red analysis. Chemical modifications of the polyurethane network also improved the thermal
and mechanical properties of the foams. In addition, isocyanate index 1.4 was determined to be the most suitable in the production
of foams from this newly synthesized epoxidized diethanolamides. 相似文献
10.
This paper discusses a rapid GC-FID technique for the simultaneous quantitative analysis of FFA, MAG, DAG, TAG, sterols, and
squalene in vegetable oils, with special reference to palm oil. The FFA content determined had a lower SE compared with a
conventional titrimetric method. Squalene and individual sterols, consisting of β-sitosterol, stigmasterol, campesterol, and
cholesterol, were accurately quantified without any losses. This was achieved through elimination of tedious conventional
sample pretreatments, such as saponification and preparative TLC. With this technique, the separation of individual MAG, consisting
of 16∶0, 18∶0, and 18∶1 FA, and the DAG species, consisting of the 1,2(2,3)- and 1,3-positions, was sufficient to enable their
quantification. This technique enabled the TAG to be determined according to their carbon numbers in the range of C44 to C56. Comparisons were made with conventional methods, and the results were in good agreement with those reported in the literature. 相似文献