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101.
优化并建立了棉仁生育酚含量的快速提取技术及高效液相色谱检测方法。样品用抗坏血酸和乙醇溶液处理后,正己烷超声萃取,以正己烷/异丙醇(100/1)流动相,采用C18色谱柱(ZORBAXRX-SIL)等度洗脱,流速0.88 m L/min,紫外检测器检测并定量(激发波长300 nm,发射波长330 nm)。测得4种生育酚的回归方程R2在0.990~0.999之间,线性关系良好;4种生育酚精密度试验结果的相对标准偏差(RSDs,n=5)均小于1%,加标回收试验的平均回收率范围在90%~105%之间,RSDs(n=3)低于7%;方法检出限范围为0.1~0.2μg/m L,定量限为0.2~0.5μg/m L。该方法作为棉仁生育酚的快速测定方法,准确、快捷、选择性好,具有较强的实用价值。  相似文献   
102.
《分离科学与技术》2012,47(16):2408-2416
Ultrasound-assisted extraction was employed to extract polysaccharides from lotus (Nelumbo nucifera Gaertn.) seeds. Response Surface Methodology was used to determine the optimal extraction conditions of ultrasound power, extraction time, and extraction temperature at 406 W, 7.7 min, and 94°C, respectively. The crude extract was successively purified by chromatography, yielding a major polysaccharide fraction termed LSPS-1. It is a heteropolysaccharide, containing rhamnose, arabinose, glucose, and galactose with a molecular weight of 4484 Da and an α-dominating configuration in pyranose form sugar. Preliminary antioxidant activity test in vitro showed LSPS-1 could potentialize the scavenging effect on hydroxyl radicals in a dose dependent manner.  相似文献   
103.
Reactive crystallization for separation and recovery of divalent metal ions from wastewater using a semi‐batch crystallizer has been developed. In this process, metal carbonates are produced by reacting metal sulfate solution with sodium carbonate solution. Nickel and copper ions are crystallized under particular initial pH conditions but the product shapes are not regular. Consequently, sphere seeds have been used as nucleus‐generating agents and their growth mechanism has been examined. When providing a particular amount of seeds before crystallization, metal substances piled up on the surface of the seeds, maintaining the form sphere, and the production of fines was restricted. The metal removal rate through reactive crystallization was ~99.9 % on average. This operation proved to be suitable for application in industrial wastewater treatment and for recycling of metal materials.  相似文献   
104.
BACKGROUND: Perilla and sesame seeds, a rich source of energy, are commonly utilized in different forms in many countries. During the post‐harvest period, they are contaminated with insects as well as microbes that may have importance for keeping quality and quarantine, and thus they can be treated with ionizing radiation for insect disinfestation and microbial decontamination. Reliable and routine methods to identify whether or not a food has been irradiated are needed to help consumers' understanding of irradiated food and promote international trade. In the present study, fat‐derived hydrocarbons from irradiated perilla seeds and sesame seeds of Korean and Chinese origin were analyzed in order to identify irradiation treatment by comparing their properties during the post‐irradiation period. RESULTS: Gas chromatographic–mass spectrometric analysis showed that several saturated hydrocarbons, such as tetradecane, pentadecane, hexadecane and heptadecane, were found in the non‐irradiated control samples, while four radiation‐induced unsaturated hydrocarbons (R2 = 0.647–0.997), such as 1,7,10‐hexadecatriene (C16:3), 1,7‐hexadecadiene (C16:2), 6,9‐heptadecadiene (C17:2) and 8‐heptadecene (C17:1), were detected in all irradiated samples at 0.5 kGy or higher, with variations according to sample and origin. Concentrations of all hydrocarbons were reduced during storage and could not be detected in 0.5 kGy irradiated Chinese sample of either seed after 8 months. CONCLUSION: Radiation‐induced hydrocarbons (C16:3, 16:2, 17:2, 17:1) could be used as markers to identify irradiated perilla and sesame seeds of both Korean and Chinese origin at 1 kGy or higher for 8 months' storage at room temperature. Copyright © 2009 Society of Chemical Industry  相似文献   
105.
堤防工程的植被防护措施   总被引:3,自引:0,他引:3  
通过试验工程,阐述了在江河堤防工程中,除采用传统工程防护措施外,还可结合植被防护措施,诸如营造固滩防浪林,采取三维网垫植草护坡及水力喷播等植被防护措施,既能提高堤坝的行洪安全性,又能改善生态环境。  相似文献   
106.
测定不同储藏条件下油葵籽生理指标的变化情况.结果表明:随着储藏时间的延长,油葵籽色泽、气味逐渐出现异常,生活力、发芽率和过氧化氢酶活度均呈逐渐下降的趋势,且温度和水分越高,下降趋势越明显.因此,低温、低水分是油葵籽安全储藏的主要条件.  相似文献   
107.
The paper aims to enlarge the current knowledge about the dependence of technological traits of wheat grain on its degree of infestation (DI) with fusariosis. Samples of grain of four wheat cultivars were obtained from naturally grown crops (control) and from crops inoculated with Fusarium culmorum from which three degrees of kernel infestation were selected. Samples were determined for thousand kernels weight (TKW), total protein, starch and wet gluten (WG) contents, Hagberg falling number (HFN) and sedimentation value (SV). Content of protein and wet gluten showed higher values for moderately infested kernels (up to 15 and 25%, respectively, when compared to control grain) than for kernels lightly or heavily infested. All the remaining traits had values lower than that for control grain and showed a decrease with increasing DI. Decrease for the heaviest infestation was on average: 8, 29, 31 and 34% for starch, TKW, HFN and SV, respectively.  相似文献   
108.
Reactive oxygen species (ROS) at physiological concentrations may be required for normal cell function. Excessive production of ROS can be detrimental to cells, because ROS can cause oxidative damage to lipids, proteins, and DNA. Herein, we describe the isolation and purification of a novel antioxidant protein the water extract of dried, powdered Sundakai (Solanum torvum [Solanaceae]) seeds. Sundakai belongs to the Solanaceae family, a small shrub, which is distributed widely in India, Malaya, China, Phillipines and tropical America. Fifty percent of ammonium sulphate-precipitated crude water extract was fractionated on a Sephadex G100 column, which yielded two peaks, PI and PII. Peaks PI and PII inhibited lipid peroxidation up to 40% and 89%, respectively in linolenic acid micelles. Rechromatographing of peak PII on Sephadex G100 yielded a single peak, indicating the homogeneity of the purified protein. SDS–PAGE analysis indicated the molecular weight of the purified protein to be ∼28 kDa. The purified protein, at 0.8 μM, inhibited deoxyribose degradation induced by generation of hydroxyl radicals by 90% and scavenged DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals by 76%. The reducing power and chelating power of the purified protein, at 0.8 μM, were found to be 72% and 85%, respectively. The protein, at 0.8 μM, also offered significant protection to calf thymus DNA damage induced by H2O2 (1 mM). Therefore, the present study demonstrates, for the first time, a novel protein from the water extract of Sundakai seeds as an excellent antioxidant.  相似文献   
109.
Pollination trials in otherwise male-free hop gardens are described. The results showed that a reduction in cone yield of up to 30% may be expected from seedless hops, but an increase in α-acid content of the cones more or less compensates for this yield reduction and the yield of α-acid per acre can be almost as high from seedless as seeded hops. Northern Brewer, in particular, performed better than other varieties when grown seedless but most of the high α-acid varieties gave reasonable results. It is suggested that the variation in response may depend on the number of resin glands present on the seeds of the different varieties, and differences in the distribution of resin glands on other parts of the cone.  相似文献   
110.
低剂量CO_2激光对茄子种子活力影响的研究   总被引:1,自引:1,他引:0  
低剂量激光照射种子对其发芽率、发芽势、酶活性均有一定的刺激效应。郝丽珍等曾在青椒上作过研究。本文在茄子上也得到了类似的结果,进而为蔬菜种子播前处理提供了依据。 1 材料和方法 茄子品种为七叶X紫茄,含水量为8.33%,试验均选用饱满的大小均一的中等种子。将种子置于自制的种盘内照射,CO_2激光扩束后功率为4.05W,光斑直径为2.5cm,照射距离为  相似文献   
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