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71.
In the paper,the relationship between the structure parameters and P V characteristics and recirculation ratio of the burner are studied by the simulated experiment of a self recirculation burner.The optimum structure parameters of the burner are analysed and tested in the cases that the produced recirculation amaunt of optimal controlled NO x consumpting the lowest energy can be ensured.  相似文献   
72.
As the research objective changing from a small simple system to a large complex one, traditional reliability theory can not adapt to the requirement of the great transformation. Based on the specialty of continuous process industry, the necessity and urgency to study the reliability of this kind of system is stated out. The research structural model of the reliability of complex continuous industries is presented also which involved in the reliability of human, network, software and devices.  相似文献   
73.
Cleaner Production must be done to achieve sustainable development. One of the most important things to develop Cleaner Production in Chongqing is to build Cleaner Production Information Database. The database confirms its purpose and function accorded with the situation of Chongqing. Furthermore, this database is designed by Delphi5 in Windows 2000 and proved to run well after debug. It can give service of technological information to Chongqing Cleaner Production.  相似文献   
74.
Based on the idea of locating the death in the collapsed area of mine by the gas released from the organism decomposition proposed by the authors, this paper presents the Least Multiply Square (LMS) model for the location and develops two kinds of ANN models for the locating computation. The results of the organism decomposition experiment indicates that the Back Propagation (BP) is better for locating the death in mine. Above works are set up the foundation of the theoretical analysis and the technical development for locating the death by analyzing the concentration distribution of the marker gas, mercaptans, in mine. Based on the technology developed, the period, for the rescue team members staying in that risk area, can be shorten. The rescue work achieve a step forward for more reasonable, feasible and efficient.  相似文献   
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In order to accelerate the working speed of a FIR filter, the structure-optimized FIR filter, which includes a vector-multiplication that can efficiently reduce the numbers of multiplication and addition of tradition structure, has been deduced .The vector-multiplication can be realized easily by means of the LUT in HDPLD FLEX10K. Using development software of MAX+PLUS II, both parallel and serial parameteized FIR filter have been designed.  相似文献   
78.
The volatile compound formation from riboflavin solution of a phosphate buffer (0.1 M, pH 6.5) under light for 15 h was studied by SPME-GC and SPME-GC/MS analysis. Only one major compound in the riboflavin solution was formed and increased as the light exposure time increased. The light-exposed riboflavin solution had a buttery odor. The compound of riboflavin solution under light was analyzed by gas chromatography and olfactometry. The major volatile compound eluted from the gas chromatograph had a buttery odor. The buttery odor compound was positively identified as 2,3-butanedione by a combination of gas chromatographic retention time, mass spectrum, and odor evaluation of authentic 2,3-butanedione. The addition of sodium azide, a singlet oxygen quencher, to riboflavin solution minimized the formation of the buttery odor compound. Singlet oxygen was involved in the formation of the buttery odor. The 2,3-butanedione was produced from the reaction between riboflavin and singlet oxygen. Singlet oxygen was formed from triplet oxygen by riboflavin photosensitization mechanism. This is the first reported oxidation reaction between riboflavin and singlet or triplet in food and biological systems.  相似文献   
79.
To protect the nutrient and flavor stability of milk under light, the effects of 0, 0.01, 0.03, and 0.05 M 1,4-diazabicyclo[2,2,2]octane (DABCO) and 2,5-dimethylfuran (DMF) on the riboflavin photosensitized oxidation of milk were studied. The oxidation of milk was studied by measuring the headspace oxygen in sample bottles after 3 h of light exposure at 3000 lux. As the concentration of DABCO and DMF, which are water soluble compounds, increased in the sample from 0, 0.01, and 0.03 to 0.05 M, the depleted headspace oxygen content significantly decreased (P < 0.05). Steady state kinetic studies of singlet oxygen oxidation showed that the antioxidant activity of DABCO and DMF was due to singlet oxygen quenching. The reaction rate constant of singlet oxygen with milk fat was 8.1 x 10(5) M(-1) s(-1). Total singlet oxygen quenching rates of DABCO and DMF were 1.5 x 10(7) and 2.6 x 10(7) M(-1) s(-1), respectively. DABCO and DMF could be used to slow the reaction between singlet oxygen and milk components to protect nutrients, especially riboflavin, and to improve the oxidative stability of milk fat during storage or processing under light.  相似文献   
80.
Ultrafiltration membrane was used to filter the Yangtze River water by powder activated carbon (PAC) pretreated, such as Tai Lake water by coagulation-sedimentation pretreatment. The changes of organic polar content were compared in each process. Combined with the scanning electron microscope(SEM) photographs of the membrane, the mechanism of slowing down membrane fouling by PAC and coagulation-sedimentation pretreatment was studied. The results showed that hydrophobic organic compounds were the main factors of membrane fouling, while hydrophilic organics had less impact. When the dosing quantity of PAC filtered by ultrafiltration membrane was 20 mg/L to pre-treat the water samples of Yangtze River, and that of polyaluminium chloride was 25 mg/L for the pretreatment of Tai Lake water samples, the flux could be recovered effectively after backwashing compared with filtering the two raw water directly. The cake layer formed on the surface of the membrane was looser after pretreatment, and could be discharged easily by periodic backwashing, The cake layer could prevent hydrophobic organic matters deposit on the surface of membrane directly, which will slow down the membrane fouling and improve the chemical safety of the membrane effluent.  相似文献   
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