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21.
Sodium stearoyl-2-lactylate (SSL), diacetyl tartaric acid esters of monoglyceride (DATEM), glycerol monostearate (GMS), and distilled glycerol monostearate (DGMS) surfactant gels were made with water and varying shortening contents. The effect of these gels on dough rheological characteristics and quality of bread was investigated. Overall, the surfactant gels improved the farinograph and extensograph characteristics of wheat flour, but the improvement reduced to some extent with the presence of shortening in the gels. Alveograph data indicated that dough properties improved with the addition of surfactant gels. Shortening in gels showed varying influence on the dough alveograph properties of wheat flour. The results indicated that the surfactant gels changed the rapid visco analyzer characteristics of wheat flour, and the presence of shortening in gels further altered the characteristics. All surfactant gels improved the volume, specific volume, texture, and overall quality scores of bread, but the improvement varied for different surfactants. By increasing the addition of shortening in gels, though the quality characteristics further improved, the response to surfactants reduced by increasing shortening content. 相似文献
22.
Noor Hazarina Hashim Jamie Murphy Nazlida Muhamad Hashim 《Journal of Computer-Mediated Communication》2007,12(3):1082-1102
In December 1996, TIME magazine published an article titled "Finding God on the Web," which projected how the Internet would shape information seeking on faith and religion. A decade later, the Web has become a popular tool for gathering religious information as well as information and imagery related to religious travel. Yet there is little research on religious destination imagery online. Imagery—positive or negative, pictographic or narrative—influences the selection of tourism destinations. This study explored online Muslim images in Malaysia via interviews and content analyses of pictures and text on tourism destination websites' homepages. The results reveal minimal portrayal of Muslim images by Malaysian tourism destination organizations. This study adds to the small body of research, especially in Muslim countries, on online religious imagery and suggests avenues for tourism operators in Malaysia and elsewhere to improve their online image with both Muslim and non-Muslim travelers. 相似文献
23.
This article reviews the production scheduling problems focusing on those related to flexible job-shop scheduling. Job-shop and flexible job-shop scheduling problems are one of the most frequently encountered and hardest to optimize. This article begins with a review of the job-shop and flexible job-shop scheduling problem, and follow by the literature on artificial immune systems (AIS) and suggests ways them in solving job-shop and flexible job-shop scheduling problems. For the purposes of this study, AIS is defined as a computational system based on metaphors borrowed from the biological immune system. This article also, summarizes the direction of current research and suggests areas that might most profitably be given further scholarly attention. 相似文献
24.
S.M. Azizi 《International journal of control》2013,86(5):876-894
In this article, the cooperative fault accommodation in formation flight of unmanned vehicles is investigated through a hierarchical framework. Three levels are envisaged, namely a low-level fault recovery (LLFR), a formation-level fault recovery (FLFR) and a high-level (HL). In the LLFR module, a recovery controller is designed by using an estimate of the actuator fault. A performance monitoring module is introduced at the HL hierarchy to identify a partially low-level (LL) recovered vehicle due to inaccuracy in the fault estimate which results in violating the error specification of the formation mission. The HL supervisor then activates the FLFR module to compensate for the performance degradations of the partially LL recovered vehicle at the expense of the other healthy vehicles. Both centralised and decentralised control approaches are developed for our proposed cooperative fault recovery technique. A robust H ∞ controller is designed in which the parameters of the controller are adjusted to accommodate for the partially LL-recovered vehicle by enforcing that the other healthy vehicles allocate more control effort to compensate for the performance degradations of the faulty vehicle. Numerical simulations for a formation flight of five satellites are provided in the deep space, which do indeed confirm the validity and effectiveness of our proposed analytical work. 相似文献
25.
A. K. Arof Z. Osman N. M. Morni N. Kamarulzaman Z. A. Ibrahim M. R. Muhamad 《Journal of Materials Science》2001,36(3):791-793
The system chitosan : ethylene carbonate : LiCF3SO3 was prepared by the solution cast technique. To verify that the conductivity of the material is due to the salt, the electrical conductivity at room temperature of the chitosan acetate film and that of the chitosan acetate films containing different amounts of ethylene carbonate added to it were measured. The order of magnitude of the electrical conductivity was 10–10 S cm–1. Films containing fixed content of chitosan and plasticizer but different amounts of salt were then prepared in the same manner and the highest electrical conductivity obtained was 1.3 × 10–5 S cm–1 at room temperature. These results indicate that the conductivity is due to the salt. Conductivity-temperature studies show that the ln T versus 103/T graphs obey Arrhenius rule implying that the conductivity occurs by way of some thermally assisted mechanism. Polarization current measurement shows that the lithium ion transference number is 0.09. A LiMn2O4/chitosan-LiCF3SO3/C cell was fabricated which cycled between 1.5 to 2.5 V with fading capacity. This could be the result of LiF formation due to interaction between the salt and the fluorine in the binding agent. 相似文献
26.
Seyed Jalal Hashemi Hassan Moslemi Naeini Gholamhosein Liaghat Roohollah Azizi Tafti Farzad Rahmani 《Journal of Materials Engineering and Performance》2013,22(1):57-63
Reduction of weight and increase of corrosion resistance are among the advantageous applications of aluminum alloys in automotive industry. Producing complicated components with several parts as a uniform part not only increases their strength but also decreases the production sequences and costs. However, achieving this purpose requires sufficient formability of the material. Tube hydroforming is an alternative process to produce complex products. In this process, the higher the material formability the more uniform will be the thickness distribution. In this research, tube hydroforming of aluminum alloy (AA1050) at various temperatures has been investigated numerically to study temperature effect on thickness distribution of final product. Also a warm hydroforming set-up has been designed and manufactured to evaluate numerical results. According to numerical and experimental results in the case of free bulging, unlike the constrained bulging, increase of the process temperature causes more uniform thickness distribution and therefore increases the material formability. 相似文献
27.
In this study, the effects of simultaneous co-deposition of polytetrafluoroethylene (PTFE) and MoS2 particles on tribological properties of electroless nickel (EN) coating were studied. The influences of specimen orientation
and heat treatment on EN-PTFE-MoS2 composite coatings were also investigated. Scanning electron microscopy was used to study the morphology of coatings and
the distributions of the lubricant particles in the deposits. Chemical analyses of coatings were done by electron dispersive
spectrometry. The phases of the coatings were identified by X-ray diffraction utilizing CuKα radiation. Wear and friction
properties of the coatings were also determined by pin-on-disk wear tester. The wear investigations showed that the EN-PTFE-MoS2 composite coating performs better than EN-PTFE and EN-MoS2 coatings in terms of friction coefficient and wear resistance. PTFE and MoS2 contents of the EN-PTFE-MoS2 coating were increased by changing the specimen orientation from vertical to horizontal configuration, which leads to enhancement
in tribological properties of the coating. After heat treatment, the wear rate of EN matrix composite coating decreased with
corresponding change in phase structure. 相似文献
28.
This research work focuses on the utilization of coconut shell powder (CSP) as filler in recycled polypropylene (rPP). Sodium Dedecyl Sulfate (SDS) was used as coupling agent in these composites. The effect of filler content and SDS on tensile properties, thermal properties, water absorption and morphology of rPP/CSP composites were investigated. In this study, modified rPP/CSP composites with SDS show significant increased tensile propertied, thermal stability, crystallinity and low water absorption compared unmodified rPP/CSP composites. Those improvements were contributed by the coupling effect of SDS. 相似文献
29.
Mohd Sufri Mastuli Norlida Kamarulzaman Mohd Azizi Nawawi Annie Maria Mahat Roshidah Rusdi Norashikin Kamarudin 《Nanoscale research letters》2014,9(1):134
In the preparation of nanostructured materials, it is important to optimize synthesis parameters in order to obtain the desired material. This work investigates the role of complexing agents, oxalic acid and tartaric acid, in the production of MgO nanocrystals. Results from simultaneous thermogravimetric analysis (STA) show that the two different synthesis routes yield precursors with different thermal profiles. It is found that the thermal profiles of the precursors can reveal the effects of crystal growth during thermal annealing. X-ray diffraction confirms that the final products are pure, single phase and of cubic shape. It is also found that complexing agents can affect the rate of crystal growth. The structures of the oxalic acid and tartaric acid as well as the complexation sites play very important roles in the formation of the nanocrystals. The complexing agents influence the rate of growth which affects the final crystallite size of the materials. Surprisingly, it is also found that oxalic acid and tartaric acid act as surfactants inhibiting crystal growth even at a high temperature of 950°C and a long annealing time of 36 h. The crystallite formation routes are proposed to be via linear and branched polymer networks due to the different structures of the complexing agents. 相似文献
30.