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71.
72.
T. RONALD A. MAGEE CAROLE P.D. WILKINSON 《International Journal of Food Science & Technology》1992,27(5):541-549
Investigation of the effects of varying air velocity, slice thickness, and pre-treatment with sodium chloride solutions and surface active agents on drying potato slices indicated that the drying occurred entirely in the falling rate period and was controlled by the mechanism of liquid diffusion. The rate of drying, and therefore the diffusion coefficients, increased with the addition of sodium chloride and surface active agents. Diffusion coefficients were also influenced by air velocity and slice thickness, suggesting that the rate of drying of potato slices is controlled by a combination of internal and external resistances. 相似文献
73.
In the first half of the paper, various types of processing pertaining to a polygon, using the 4×4 determinant theories are explained along with a new containment test algorithm of a point in a polygon. In the latter half of the paper, a general-purpose geometric processor, the POLYGON ENGINE, is presented which can deal with various types of interference problems, such as Boolean operations in solid modelling, hidden line and surface eliminations, ray tracing and so on. It is, a successor of the TRIANGLE PROCESSOR and is also based upon the 4×4 determinant theories [4–6]. While the TRIANGLE PROCESSOR processes a triangulated polygon on a triangle-by-triangle basis, the POLYGON ENGINE can treat a polygon without triangulation. The latter is expected to be more functional, more efficient and easier to use. 相似文献
74.
聚丙烯表面改性及与涂料的粘结 总被引:3,自引:2,他引:1
刘景江 《高分子材料科学与工程》1992,8(5):1-5
讨论了聚丙烯制品喷涂着色的优点及影响聚丙烯制品与涂料之间粘结强度的各种因素。综述和评价了对聚丙烯进行表面改性的必要性及各种表面改性方法。 相似文献
75.
76.
显式BEZIER三角曲面的构造及其在离散数据插值中的应用 总被引:1,自引:0,他引:1
本文较系统地讨论了显式Bezier三角曲面的Clough-Tocher分割构造方法,并从工程应用角度提出了一种准C‘连续的Bezier三角曲面。由这种准C‘连续的Bezier三角曲面,通过进一步求解整体C‘连续的Bezier三角曲面在解决3D离散数据的曲面插值中取得了较好的应用效果。 相似文献
77.
海湾战争中,“爱国者”导弹成功地拦截了“飞毛腿”导弹,给近程地对地战术导弹的作用、发展与装备方向提出了值得思考的问题。本文着重讨论在局部战争中,近程地对地战术导弹的作用、使用场合及其技术发展方向。 相似文献
78.
Blaise P. Nic Phiarais Beatus D. Schehl Jorge C. Oliveira Elke K. Arendt 《Journal of the Institute of Brewing》2006,112(4):324-332
The influence of two factors, total concentration and fraction of three pairs of commercial enzymes, which showed statistical significance (Biocellulase W with Hitempase 2XL, Biocellulase W with Amylo 300 and Amylo 300 with Hitempase 2XL), were studied for their overall effect on buckwheat wort quality using response surface methodology (RSM). This study revealed that the addition of increasing levels of Hitempase 2XL to the buckwheat mash increased colour, extract levels, wort filtration, fermentability and total fermentable extract (TFE), along with decreasing viscosity values. Results also determined a high level of fermentability when an enzyme combination of 30% Biocellulase and 70% Hitempase was added to the mash. The addition of increasing levels of Amylo 300 to buckwheat mashes resulted in increases in fermentability and total fermentable extract (TFE), along with increases in total soluble nitrogen (TSN), free amino nitrogen (FAN) and Kolbach index (KI). With regard to the proposed optimal regime, although no synergistic effect was found when the three enzymes were used together, the optimum conditions for the production of buckwheat wort with lowest viscosity, highest extract and optimal fermentability were achieved using a joint model. Overall, the findings of this study demonstrate the feasibility of producing wort suitable for the brewing of gluten‐free beer from 100% malted buckwheat with careful optimisation of enzyme types and dosage levels. 相似文献
79.
A new curvature technique calculation for surface tension contribution in PLIC-VOF method 总被引:1,自引:0,他引:1
The volume of fluid (VOF) methods have been used for numerous numerical simulations. Among these techniques used to define
the moving interface, the piecewise linear interface reconstruction (PLIC-VOF) is one of the most accurate. A study of the
superficial tension impact on two-phase flow with free surface is presented. A new method based on direct staggered grid is
developped to include surface tension in PLIC-VOF. The new numerical curvature calculation method doesn't need smoothed colour
function and leads to less “spurious current”. This technique is applied to the calculus of surface tension force in the case
of the rise of air bubble in viscous liquid and the fall of liquid drop in the same liquid on free surface. Droplets, thin
layer and capillarity waves are observed after the free surface rupture for different Bond number. The influence of surface
tension calculus is then obvioused and when the drop hit the free surface, wavelets propagate toward the virtual boundaries
imposed. 相似文献
80.
Narendra Singh Shah & Nirankar Nath 《International Journal of Food Science & Technology》2006,41(9):1073-1081
Litchi (Litchi chinensis Sonn.) fruits are very susceptible to pericarp browning which adversely affects consumer acceptability even though the aril portion remains in excellent condition. Litchi arils (litchis) were treated with a solution containing 0–2% (w/v) calcium lactate (CL), 0–0.02% (w/v) 4‐hexyl resorcinol (4‐HR) and 1% potassium sorbate. The pH of solution was adjusted to 4.0 with citric acid. Treated litchis were packed in polystyrene trays, over‐wrapped with polypropylene film, vacuum‐packed (0, 47409.3, 94831.9 Pa) and stored at 4 ± 2 °C. Drip losses, pH, total soluble solids (TSS), sensory attributes and microbiological quality of stored samples were estimated. A four‐factor, three‐level experimental design (D6 Hokes design) with 19 experiments was chosen. Mathematical models were developed to analyse and predict the effect of CL, 4‐HR, in‐package vacuum and storage time on the responses. TSS, pH and sensory scores decreased significantly (P 0.01), whereas drip losses and microbial count increased significantly (P 0.01) with time. Drip loss was significantly (P 0.1) reduced by addition of CL. 4‐HR prevented browning and changes in colour score during storage were significantly less. Vacuum in packages exerted significant (P 0.01) effect over pH, TSS, sensory and microbiological qualities of minimally processed litchis. 相似文献