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101.
Cheng-Hung Huang Wei-Cheng Tseng 《International Journal of Mechanics and Materials in Design》2016,12(2):223-240
An inverse design problem in determining the optimal shape of volute spiral case for a centrifugal-flow fan is examined in the present study using the Levenberg–Marquardt method and a general purpose commercial code CFD-ACE+, and based on a desired airflow rate. The desired volume airflow rate can be obtained by multiplying the airflow rate of an existing fan by a constant number which is >1. The shape of the redesigned volute case is generated using the equation of the trajectory of fluid particles in the volute, which enables the shape of the fan volute be constructed completely. Finally, prototypes of the original and optimized fan volutes as well as fan impellers are fabricated, thereafter the fan performance is tested based on the AMCA-210-85 standard to verify the validity of the design. The experimental results demonstrate that by utilizing the fabricated centrifugal optimal fan and operating at the design condition, the airflow rate can be increased by 6.5 % and the pressure drop, noise and input power of fan can be reduced by 1.6, 5.3 and 11.4 %, respectively, when compared with the original fan. As a result, the performance of optimal fan can be improved greatly. 相似文献
102.
Most research of run-to-run process control has been based on single-input and single-output processes with static input–output relationships. In practice, many complicated semiconductor manufacturing processes have multiple-input and multiple-output (MIMO) variables. In addition, the effects of previous process input recipes and output responses on the current outputs might be carried over for several process periods. Under these circumstances, using conventional controllers usually results in unsatisfactory performance. To overcome this, a complicated process could be viewed as dynamic MIMO systems with added general process disturbance and this article proposes a dynamic-process multivariate exponentially weighted moving average (MEWMA) controller to adjust those processes. The long-term stability conditions of the proposed controller are derived analytically. Furthermore, by minimizing the total mean square error (TMSE) of the process outputs, the optimal discount matrix of the proposed controller under vector IMA(1,?1) disturbance is derived. Finally, to highlight the contribution of the proposed controller, we also conduct a comprehensive simulation study to compare the control performance of the proposed controller with that of the single MEWMA and self-tuning controllers. On average, the results demonstrate that the proposed controller outperforms the other two controllers with a TMSE reduction about 32% and 43%, respectively. 相似文献
103.
Lu-Yen Chen Chung-Hwei Su Kuen-Yuan Chuang Chun-Ping Lin Shuh-Woei Yu Jo-Ming Tseng 《Korean Journal of Chemical Engineering》2012,29(10):1292-1297
Tert-butyl(2-ethylhexyl)monoperoxy carbonate (TBEHC) 95 mass% is intrinsically a very unstable substance that can induce self-decomposition even under normal atmospheric condition. During storage, TBEHC 95mass% can release an enormous amount of heat if the temperature is higher than the recommended storage temperature, due to the self-accelerating reaction having been ignited. In this study, TBEHC 95mass% was tested by differential scanning calorimetry (DSC) under five heating rates (1, 2, 4, 6, and 8 °C/min) and four isothermal conditions (120, 125, 130, and 135 °C) to evaluate the basic kinetic and safety parameters of time to maximum rate (TMR), self-accelerating decomposition temperature (SADT), and temperature of no return (TNR). Under runaway reaction TBEHC 95 mass% releases a great quantity of heat. This study establishes an important guiding principle for related manufacturing processes worldwide. 相似文献
104.
Kuo-Hsiung Tseng Juei-Long Chiu Heng-Lin Lee Yi-Syuan Kao Der-Chi Tien 《Materials and Manufacturing Processes》2016,31(2):186-193
This study developed a system monitoring the electric discharge machine's (EDM) discharge energy and success rate to replace conventional oscilloscope observation. By using logic circuit, the signals are transmitted to the PC monitoring platform in order to display the discharge success times, discharge success rate, and electrode's consumption energy. The advantage of the proposed system is the capability to observe real-time discharges and record the experimental conditions, as well as optimize the discharge parameter settings. The experimental results suggest that, in the preparation of nanosilver colloid, the cost-performance of Ton–Toff at 10–100 µs is the optimal setting. The monitoring system also can take advantage of the discharge success rate to control the energy consumption of the electrode to obtain the standardization of products. The results suggest that, while discharge success rate, electrode's weight loss and wavelength of the absorption peak are considerably accurate, but concentration accuracy is relatively poor. The discharge success rate monitoring system is an innovative method that can help to realize electric discharge processing, optimize product quality, and it may be a powerful processing tool in the future. 相似文献
105.
James Won-Ki Hong Yuan-Kuang Tu Choong Seon Hong Shian-Shyong Tseng Yoshiaki Kiriha Han-Chieh Chao Marat Zhanikeev Wang-Cheol Song 《Journal of Network and Systems Management》2012,20(1):134-142
This article presents a report on APNOMS 2011, which was held September 21–23, 2011 in Taipei, Taiwan. The theme of APNOMS
2011 was “Managing Clouds, Smart Networks and Services.” 相似文献
106.
Abstract In this paper, we present a multi‐purpose medical diagnostic system named AEA — the Acute Exanthem Advisor, and the methodologies of its implementation. AEA provides an accurate diagnosis of acute exanthemas and a complete environment including a user‐friendly interface, reviewing function, record keeping function and explanation function. Therefore, it may serve as an assistant, a record keeper or an educational tool. A prediction program is also provided which is capable of predicting the number of potential patients who are going to have acute exanthemas in the near future. To illustrate the processes of the consultation and the prediction of the AEA, an example is given. Finally, for the 25 different test cases given to the diagnosticians and the AEA, the answers are almost the same, so we can conclude that the performance of the AEA is satisfactory. Now, we are trying to extend the AEA system to be a medical diagnostic net for acute exanthemas, which will be able to be remote accessed through network communications. 相似文献
107.
Shr-Nan Bai Tseung-Yuen Tseng 《Journal of Materials Science: Materials in Electronics》2009,20(7):604-608
ZnO nanowire arrays have been grown on the ZnO film-coated silicon (100) substrates by hydrothermal method, and the deposited
nanowires are found to have a uniform size distribution with sharp hexagonal-shaped tips. The structural and optical properties
of the nanowires were investigated using atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy
(SEM), transmission electron microscopy (TEM), and cathodoluminescence (CL) techniques. The XRD and SEM results demonstrate
that the well-aligned ZnO nanowires are single crystalline structure formed along the c-axis orientation. TEM analysis further
confirms that the ZnO nanowires are highly preferred grown along the (002) crystal plane. The spacing between adjacent (002)
lattice planes is estimated as 0.52 nm. The optical properties of the nanowires were measured using CL after annealing in
oxygen and nitrogen atmospheres at 550 °C for various times. The CL spectra in the visible spectrum exhibit two weak deep-level
emission bands that may be attributed to the intrinsic or extrinsic defects. It can be observed that the ZnO nanowires show
different optical behaviors after various annealing times. The dependence of the optical properties on the annealing conditions
is also discussed. 相似文献
108.
109.
Self‐Crack‐Filled Graphene Films by Metallic Nanoparticles for High‐Performance Graphene Heterojunction Solar Cells 下载免费PDF全文
110.
Greta Jarockyte Egle Daugelaite Marius Stasys Urte Statkute Vilius Poderys Ting-Chen Tseng Shan-Hui Hsu Vitalijus Karabanovas Ricardas Rotomskis 《International journal of molecular sciences》2016,17(8)
The uptake and distribution of negatively charged superparamagnetic iron oxide (Fe3O4) nanoparticles (SPIONs) in mouse embryonic fibroblasts NIH3T3, and magnetic resonance imaging (MRI) signal influenced by SPIONs injected into experimental animals, were visualized and investigated. Cellular uptake and distribution of the SPIONs in NIH3T3 after staining with Prussian Blue were investigated by a bright-field microscope equipped with digital color camera. SPIONs were localized in vesicles, mostly placed near the nucleus. Toxicity of SPION nanoparticles tested with cell viability assay (XTT) was estimated. The viability of NIH3T3 cells remains approximately 95% within 3–24 h of incubation, and only a slight decrease of viability was observed after 48 h of incubation. MRI studies on Wistar rats using a clinical 1.5 T MRI scanner were showing that SPIONs give a negative contrast in the MRI. The dynamic MRI measurements of the SPION clearance from the injection site shows that SPIONs slowly disappear from injection sites and only a low concentration of nanoparticles was completely eliminated within three weeks. No functionalized SPIONs accumulate in cells by endocytic mechanism, none accumulate in the nucleus, and none are toxic at a desirable concentration. Therefore, they could be used as a dual imaging agent: as contrast agents for MRI and for traditional optical biopsy by using Prussian Blue staining. 相似文献