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991.
Regional manufacturing information engineering industries are extremely large and complex systems. Based on the implemental integer effect and an evaluation requirement of regional manufacturing information engineering, we analyzed the objectives and characteristics of regional manufacturing information engineering, proposed a multiple evaluation index method of regional manufacturing information engineering. Based on a multiple integration evaluation method, we built a model to evaluate regional manufacturing information engineering. We proposed a measurement model for regional manufacturing information engineering based on multi level fuzzy comprehensive evaluation. Our quantitative research regarding the implementation effectiveness of regional manufacturing information engineering was based on fuzzy quantitative indicators. The model was grounded on collecting indexes of regional manufacturing industry information engineering, and used a fuzzy matrix to normalize the assessment results to a single fuzzy comprehensive evaluation level. Measurement was carried out step by step. Multi level comprehensive evaluation results for a regional manufacturing information engineering industry were obtained. The validity of the model was shown through application practice.  相似文献   
992.
Addressing the problem of choosing a fault line under single phase to ground of distribution network, we presented a new criterion based on analysis of the development of fault line selection and a method using wavelet packets. The feature frequency band, or the combined feature frequency bands of each line, in which the transient capacity current was concentrated was chosen for maximum energy. Based on the principle that the transient capacity current's energy of the fault line was larger than the that of normal lines, fault line selection can be carried out adaptively by contrasting the energy of the transient capacity currents of all lines in each chosen frequency band. The simulation results and spot testing data shows the proposed method can detect the fault line in distribution networks precisely and reliably.  相似文献   
993.
An orphogonal frequency division multiplexing(OFDM) based cognitive radio architecture was designed to meet the transmission requirements of a cognitive radio system. After finishing the allocation of subtransmission, and keeping BER within the limit that ensures service quality, an adaptive bit allocation method was proposed to allocate the bit and energy of subtransmission dynamically. The total power for launching needed reached its minimum (or SNR per bit reached its maximum). Compared with the fixed bit allocation method, the proposed method is simpler, decreases the system transmission power, and has better BER performance.  相似文献   
994.
We developed a process model of flame beam transmission using pulverized coal powder and coke combustion in a raceway. We employed a Monte Carlo computation method equation based on charge couple devrce(CCD) target heat flow distribution for radiation heat transfer. We explored the factors impacting radiation transmission. Based on these, a three dimensional reconstruction was analyzed at varying coke particle concentrations. This model provided an effective method to produce on line monitoring of raceway working states.  相似文献   
995.
Based on the model proposed by Tiwari and Patil, we improved the calculation method for surface energy, and calculated the vacancy formation energy for typical metals such as fcc, bcc and hcp metals. The calculated results and experimental values agree with each other when an energy modification coefficient is introduced. The energy modification coefficients of fcc, bcc and hcp metals are 1.292, 1.265 and 1.357, respectively. The proposed method can calculate and predict the vacancy formation energy of metals efficiently.  相似文献   
996.
We investigated the removal effects of chloride ion on treating organic substances with electrolysis using leachate from semi aerobic bioreactors. The experimental results show that, under the given conditions, the removal efficiency of refractory organic substances increases with rising initial chloride ion concentration in leachate. The impact of chloride ion on removal efficiency mainly is influenced by the initial chloride ion concentration and the chemical oxygen demand (COD) in leachate. The impact of chloride ion on the specific electric consumption of removal COD is obvious when the initial chloride ion concentration is lower. No obvious change of this impact is observed when the chloride ion concentration exceeds 125 g/L. Meanwhile, the more obvious impact of initial chloride ion concentration on organic substance removal is observed when the COD concentration in leachate is lower.  相似文献   
997.
The self heating of coal is influenced by many factors, but mainly it involves exothermic reactions between reactive sites in the coal and oxygen from the air. Moisture affects the nature of the radical sites where oxidation occurs, and affects the tendency of coal to combust spontaneously. Adiabatic tests show the coal self heating rate increases as the moisture content increases. At approximately 40% to 50% of the moisture holding capacity of the coal, the self heating rate becomes measurable. Above this critical level of moisture content, the heat produced by oxidation is dissipated by moisture evaporation and coal self heating is significantly delayed.  相似文献   
998.
In order to meet the performance demands of train lorry, a die forging drawing method based on structure features analysis was proposed to form the L A break beam frame. The finite element method was used to simulate a series of die forging processes and the drawing processes with different parameters. The optimum cross section shape of the performing die was obtained from these simulation results. It is found that local back flow of the metal is the primary cause of necking defects in drawing. Furthermore, the best drawing speed is determined to be from 87 mm/s to 96 mm/s. The results of trial manufacturing and product detection indicate that employing a die forging drawing process to form the monobloc break beam frame is feasible.  相似文献   
999.
A supercritical CO2 fluid extraction (SFE) method was developed to extract isoflavone. A uniform design was used to investigate the effect of the extraction pressure, extraction time, extraction temperature, and medicinal materials granularity on isoflavone extraction efficiency. The optimum conditions of extraction were as follows: 45 MPa extraction pressure, 50 ℃ extraction temperature, 4 h extraction time, 40 eyes medicinal materials granularity, and the extraction efficiency was (0.361±0.012)%.  相似文献   
1000.
The conductivity of a TiO2 cathode in the FFC process was studied by sintering and electrolyzing experiments. Sintered TiO2 cathode and electrochemical reduction of TiO2 were measured using X ray diffraction. Results show that changing the energy band structure of TiO2 via high temperature sintering can cause electric conduction vacancy. An electric double layer can be formed in molten salt. Ionization of oxygen atoms leads to formation of TiO2 x ionic structures. The ions infiltrate to the electrode in molten salt, increasing the number of conduction ions. The electrolyzing process proceeds smoothly, based on the integrated mechanism of activating the TiO2 cathode. The activated TiO2 cathode can be obtained by forming electric conduction vacancy at high temperature sintering, the TiO2 x ionic structure by electric double layer, and ions infiltrating to the interior of the electrode.  相似文献   
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