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91.
Disassembly is a critical step to increase the value of end-of-life (EOL) products and to reduce the environmental footprint. Despite worldwide efforts, disassembly is still performed manually due to the uncertainty associated with the quality and the quantity of the returned EOL products. In this paper, a cognitive robotics based system is proposed to address this problem. The system is equipped with four cognitive functions: reasoning, execution monitoring, learning and revision. The proposed system is tested using LCD screens. The results show that the system is flexible enough to deal with any product models without prior information. 相似文献
92.
Vijay Srinivasan J. Sami Cuzmar Thomas J. O’keefe 《Metallurgical and Materials Transactions B》1990,21(1):81-86
The presence of excessive lead in zinc sulfate electrolytes can lead to problems related to both processing efficiency and
the properties of the metal produced. For example, poor adhesion can occur in electrogalvanized steel when it is heated in
the temperature range of 215 °C to 280 °C if lead is present in the deposit. The duration of heating necessary to induce the
peeling of the zinc was found to be dependent on the temperature, time, and concentration of lead in the electrolyte and the
plating parameters. The presence of lead slowed the formation of the intermetallic, and the peeling occurred between the zinc
and the iron-zinc intermetallic layer. In order to gain a better fundamental understanding of the role of lead, rotating disc
electrodes were used to measure the diffusion coefficient of lead in the zinc sulfate electrolyte. The experimentally determined
mass transport data on lead can be used as an aid to set an acceptable limit of lead allowable in the electrolyte or to evaluate
the electrochemical characteristics of an electrolytic zinc system. By the addition of strontium carbonate to the plating
solution followed by filtration, the lead concentration in the electrolyte could be reduced to an acceptable level, preventing
the poor adhesion on heating. 相似文献
93.
Sami S. Ashour Edward B. Rinker Orville C. Sandall 《Chemical Engineering Communications》1997,161(1):15-24
Experimentally measured diffusion coefficients of nitrous oxide in water, aqueous solutions of diethanolamine, aqueous solutions of N-methyldiethanolamine, and aqueous blends of diethanolamine and N-methyldiethanolamine have been used to arrive at a modified Stokes-Einstein correlation by using nonlinear least-squares filling. The average deviation of this correlation from the experimentally measured diffusion coefficients is about 13%. Comparisons are also made to the estimated diffusivities of nitrous oxide in the amine solutions which are obtained from the Wilke-Chang and Hayduk-Minhas correlations. The average deviations of the Wilke-Chang and Hayduk-Minhas correlations from the measured values are about 13% and 19%, respectively. Correlations were also presented for estimating the solution densities and viscosities. Predicted values for the solution densities and viscosities from these correlations deviate from experimentally measured values on average by 1.2% and 4.8% respectively. 相似文献
94.
Location-Aided Handover in Heterogeneous Wireless Networks 总被引:1,自引:1,他引:0
Pesola Juuso Pönkänen Sami Markopoulos Antonis 《Wireless Personal Communications》2004,30(2-4):195-205
The concept of being always online, regardless of the time and place, has been one of the hot topics in the commercial and scientific forums during the last years. The term itself is not solidly defined, however it is often used to refer to user's ability to get the same services via changing variety of underlying networks. In order to really work, this kind of multiaccess in heterogeneous networks still requires research, technological achievements and even compromises. The key to successfully implement the multiaccess is vertical handover that allows the application services to be seamlessly transferred between different networks. 相似文献
95.
Eleonora Papadimitriou Athanasios Theofilatos George Yannis Julien Cestac Sami Kraïem 《Accident; analysis and prevention》2014
Riding a motorcycle under the influence of alcohol is a dangerous activity, especially considering the high vulnerability of motorcyclists. The present research investigates the factors that affect the declared frequency of drink-riding among motorcyclists in Europe and explores regional differences. Data were collected from the SARTRE-4 (Social Attitudes to Road Traffic Risk in Europe) survey, which was conducted in 19 countries. A total sample of 4483 motorcyclists was interviewed by using a face-to-face questionnaire. The data were analyzed by means of multilevel ordered logit models. The results revealed significant regional differences (between Northern, Eastern and Southern European countries) in drink-riding frequencies in Europe. In general, declared drinking and riding were positively associated with gender (males), increased exposure, underestimation of risk, friends’ behaviour, past accidents and alcohol ticket experience. On the other hand, it was negatively associated with underestimation of the amount of alcohol allowed before driving, and support for more severe penalties. 相似文献
96.
Ca2Ce2Ti5O16 dielectric ceramics prepared by conventional solid-state ceramic route was investigated. Phase composition and microwave dielectric properties were measured using XRD and Vector network analyzer, respectively. XRD analysis of the calcined and sintered samples revealed the formation of CeO2 and another unidentified phase (that vanished at ? 1400 °C) as secondary phases along with the parent Ca2Ce2Ti5O16 phase. The amount of the parent Ca2Ce2Ti5O16 phase increased with increasing sintering temperature from 1350 °C to 1450 °C accompanied by a decrease in the apparent density. The density decreased but ? r and Q u f o increased with sintering temperature. An ? r ~ 81.5, Q u f o ~ 5915 GHz and τ f ~ 219 GHz were achieved for the sample sintered at 1450 °C. 相似文献
97.
Juan Li Xuelin Tian Alexander Pyymaki Perros Sami Franssila Ville Jokinen 《Advanced Materials Interfaces》2014,1(3)
A radial pattern with continuous topography gradient is presented, which induces a continuous inward wettability gradient and enables self‐propelling and accurate positioning of droplets to the pattern center. The effect of droplet size and wettability gradient of the pattern on the self‐mobility of droplets is investigated. The wettability gradient is found to increase towards the pattern center, enhancing the self‐motion of droplets at the inner area of the pattern. Moreover, larger droplets give rise to a larger solid‐liquid contact diameter, which helps to satisfy the self‐motion criteria that the advancing contact angle at front edge is smaller than the receding contact angle at rear edge. Consequently, a larger droplet size favors self‐motion initiated from the outer area of the pattern. The continuous topography gradient employed here allows the flexible dispensing of droplets at any place within a certain range, and avoids potential pinning defects to droplets at geometrical discontinuities. An average self‐motion velocity up to 4.0 cm/s for microliter‐sized droplets is achieved on the resultant patterned surface. 相似文献
98.
Bassam A. Jubran Hilal A. Al-Hinai Yousef H. Zurigat Sami Al-Salti 《Renewable Energy》2003,28(10):1545-1553
This paper reports on the feasibility of using various Photovoltaic (PV) systems namely; Grid PV (GPV), Stand-Alone PV (SAPV), Grid PV Wind (GPVW) and PV Wind (PVW) for supplying the power requirements of a window-type air-conditioning system or other small loads. It was found that the GPVW system is the best system to meet the load requirement of a window-type air-conditioning system under the climatic conditions of Oman with values ranging from $39,500 to $56,500 for the capital cost and $9,000 to $33,000 for the total net capital cost depending on the wind speed. These values are attractive for remote off grid applications. 相似文献
99.
100.