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61.
米糠油主要由油酸、亚油酸和棕榈酸组成,属半干性油,具有了作为涂料基料的良好理化特性。研究表明,选用米糠油、桐油、环氧树脂和氧化铁红合成的铁红环氧酯防锈底漆,具有无毒、低温固化、防锈能力强等特点。本介绍了底漆的配方、生产工艺,并讨论了影响底漆性能的因素。 相似文献
62.
Sweet potato pulp (SSP) obtained as a by‐product from starch extraction was blended with polycaprolactone (PCL) to prepare a biodegradable plastic material. In the blends, PCL was used as a reinforcing agent. The SPP/PCL blends were prepared by compression‐molding under high temperature and pressure, at different SPP/PCL ratios, and the mechanical properties of the molded specimens were tested. Matrix structure and thermal properties were measured by using a Fourier transform infrared (FTIR) spectrophotometer, scanning electron microscope (SEM), differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). Mechanical properties (tensile and flexural properties) were also measured to find the most suitable ratio in a SSP/PCL blend. During compression molding of the SPP/PCL blends under high pressure and temperature, chemical reaction occurred between SPP and PCL, and thus, thermal stability and mechanical strength of the blends increased and water uptake decreased. Also, by increasing the PCL content in the blend, the matrix in the blend became more homogeneous, and consequently, mechanical strength of the molded specimen increased. At 7/3 or 6/4 weight ratio of SSP/PCL, water uptake of the molded specimen became substantially less than that at 8/2. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 861–866, 2004 相似文献
63.
选取酰胺类、磺酰脲类、硫代氨基甲酸酯类、杂环类、脲类、苯氧羧酸类等常用化学除草剂,以超常规剂量用移液和喷雾两种方式对抛栽和直播籼、粳稻进行药剂试验。研究结果明确了各种除草剂对水稻的药害症状;籼粳稻对各药剂的敏感差异;以及清水冲洗、搁田、施肥等措施对某些除草剂品种造成的水稻药害的缓解作用。 相似文献
64.
65.
为评价除草剂四唑嘧磺隆在水稻上使用后的残留动态及环境安全性,在北京海淀区进行了50%四唑嘧磺隆水分散粒剂在水稻上的残留动态和最终残留试验研究。样品经丙酮提取抽滤后,再经液液分配及氧化铝柱净化、浓缩、定容后,用紫外检测器的液相色谱进行测定。其有效成分四唑嘧磺隆的最低检出量为0.02ng,在稻田水、土壤、鲜植株、稻壳、糙米样品中的平均回收率为82.4%-105.0%,变异系数为1.1%~14.1%,符合农药残留分析的要求。结果表明:四唑嘧磺隆在水稻植株上的半衰期为2.4d,在土壤巾的半衰期为5.5d,在稻田水中的半衰期为1.9d,施药后7d四唑嘧磺隆在水稻植株上的消解达到80%以上。50%四唑嘧磺隆水分散粒剂按80、120g/hm。使用,施药1次,收获时,四唑嘧磺降在糙米、稻壳、稻草、土壤中的残留量均未检出。 相似文献
66.
Chunduri Venkata Subrahmanyam Malapati Venkateswara Rao Vura Balasubrahmanyam Dipti Narayan Bhowmick 《European Journal of Lipid Science and Technology》2006,108(9):746-752
The procedure for the classical chemical refining of vegetable oils consists of degumming, alkali neutralization, bleaching, and deodorization. Conventional refining of rice bran oil using alkali gives oil of acceptable quality, but the refining losses are very high. A critical work has been carried out to study the application of membrane technology in the pretreatment of crude rice bran oil. Oils intended for physical refining should have a low phosphorus content, and this is not readily achievable by the conventional acid/water degumming process. The application of membrane technology for the pretreatment of rice bran oil has been investigated. The process has already been successfully applied to other vegetable oils. Ceramic membranes, which are important from the commercial point of view, were examined for this purpose. The results showed that the membrane‐filtered oils met the requirements of physical refining, with a substantial reduction in color. It was observed that most of the waxy material was also rejected. Experiments were carried out to establish the relationship between permeate flux and rejection with membrane pore size, trans‐membrane pressure and micellar solute concentration. 相似文献
67.
Johnsy George R. Kumar C. Jayaprahash A. Ramakrishna S. N. Sabapathy A. S. Bawa 《应用聚合物科学杂志》2006,102(5):4514-4522
Rice bran was incorporated into low‐density polyethylene (LDPE) at different concentrations by compounding in a twin‐screw extruder and blown into films of uniform thickness. The rice bran incorporation influenced physical, mechanical, barrier, optical, thermal properties, and biodegradation of LDPE. The mechanical and optical properties decreased as the percentage of rice bran increased. The effect of rice bran on the morphology of LDPE blends was examined using scanning electron microscopy. Oxygen transmission rate and water vapor transmission rate increased with the increased content of rice bran. Addition of rice bran did not alter the melting temperature (Tm) of the blends; however the thermal stability decreased, while glass transition temperature (Tg) increased. Kinetics of thermal degradation was also investigated and the activation energy for thermal degradation indicated that for up to 10% filler addition, the dispersion and interfacial adhesion of rice bran particles in LDPE was good. Aerobic biodegradation tests using municipal sewage sludge and biodegradation studies using specific microorganism (Streptomyces species) revealed that the films are biodegradable. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4514–4522, 2006 相似文献
68.
N. K. Fageria V. C. Baligar R. J. Wright J. R. P. Carvalho 《Nutrient Cycling in Agroecosystems》1990,21(3):157-162
Not much is known about the response of lowland rice to K fertilization under Brazilian conditions. A field experiment was conducted during four consecutive years to determine the response of three lowland rice (Oryza sativa L.) cultivars to K fertilization on a Low Humic Gley soil. In the first two years, K was broadcast at rates of 0, 42, 84, 126, and 168 kg K ha–1. In the last two years K rates were reduced to 0, 25, 50, 75, and 100 kg K ha–1 and applied in a band. Potassium significantly (P < 0.01) increased grain yields but the response varied from cultivar to cultivar and year to year. Yield responses to K fertilization were superimposed on a general trend of increasing grain yields across the four growing seasons. Mean grain yields increased 14.3% with broadcast application of K in the first two years and 10.4% with banded application of K in the last two years when compared to the control treatments. Extractable soil K increased with K application rate and decreased with soil depth. Potassium was rapidly removed from the soil and yearly broadcast or banded application of K can be expected to result in a significant increase in grain yield of lowland rice in these soils. 相似文献
69.
2005—2006年抗除草剂油菜田施用除草剂甲咪唑烟酸和阿特拉津土壤残留对后茬水稻影响的田间小区试验结果表明,甲咪唑烟酸72、108ga.i./hm^2(推荐用量范围)和高剂量144ga.i./hm^2在油菜田施用后,推荐剂量范围内对后茬水稻的产量未造成显著影响,高剂量144ga.i./hm^2对产量有显著影响,40%阿特拉津悬浮剂900、1200ga.i./hm^2(推荐用量范围)和高剂量1800ga.i./hm^2在油菜田施用后,推荐剂量范围内对后茬水稻的产量影响不显著,高剂量对水稻的产量有明显的影响。这一结果说明甲咪唑烟酸和阿特拉津在推荐剂量范围内在油菜田施用对后茬水稻的安全性。 相似文献
70.