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51.
不同钾肥配施对烤烟石油醚提取物和中性致香物质的影响   总被引:1,自引:0,他引:1  
采用田间试验,以T1(普通钾肥)为对照,研究了缓释钾肥及其与普通钾肥、黄腐酸钾的配施对烤烟石油醚提取物和中性致香物质含量的影响.结果表明T4处理(缓释钾肥+普通钾肥+黄腐酸钾)上部叶石油醚提取物含量、各类型致香物质含量和中性致香物质总量均高于其它处理,中部叶石油醚提取物含量和中性致香物质总量仅低于T3(缓释钾肥+普通钾肥),且其上部叶和中部叶分别有24和16种致香物质含量高于其它处理,是最优施钾处理.  相似文献   
52.
我国钾盐资源紧缺 ,钾肥生产不足 ,要满足我国对钾盐日益增长的要求 ,必须从长远出发 ,拓宽我国找钾新思路 ,扩大找钾范围 ,充分发挥和利用全球钾资源来解决国内钾肥短缺的问题  相似文献   
53.
探讨硼肥对番茄果实挥发性物质的影响,以陕西地区主栽番茄品种"金棚1号"为实验材料,采用叶面喷施(L)、营养液混施(W)2种不同施硼方式和1.9、3.8、5.7 mg/L的3种不同硼酸质量浓度处理,以不含硼酸营养液为对照(CK),利用顶空固相微萃取-气相色谱-质谱联用技术测定其挥发性物质成分和含量。结果表明:7种处理的番茄果实共检测出79种挥发性成分,主要包含醛类、酯类、醇类、烯烃类和酮类等物质。挥发性物质成分总含量从高到低顺序依次为:不含硼酸营养液+叶面喷施1.9 mg/L硼酸(L1)含3.8 mg/L硼酸营养液(W2)含1.9 mg/L硼酸营养液(W1)不含硼酸营养液+叶面喷施5.7 mg/L硼酸(L3)含5.7 mg/L硼酸营养液(W3)不含硼酸营养液+叶面喷施3.8 mg/L硼酸(L2)不含硼酸营养液(CK);且共包含了14种特征香气物质,其特征香气成分总含量从高到低排序为:W2L1L3W1W3L2CK。此外,相同硼肥质量浓度不同施用方式和相同施用方式不同硼肥质量浓度水平对番茄特征效应化合物影响不同,含3.8 mg/L硼酸营养液处理番茄果实检测出全部14种特征香气物质,包含果香型、青香型和花香型3种类型香气成分,且果香型香气成分含量最高,其中对香气含量贡献最大的为6-甲基-5-庚烯-2-酮,因而香气成分表现丰富。因此,施用含3.8 mg/L硼酸营养液可以使番茄果实的果香味浓厚且香气物质丰富。  相似文献   
54.
The fertilizer potential of two unusual N-P compounds with cage structures was evaluated in pot experiments where plants were repetitively cut over 400 days. One of the compounds, hexamethyl-hexaaza-tetraphosphaadamantane (APA), having 41.6% P and 28.2% N, showed high fertilizer capability. After more than 400 days, dry matter yield of Rhodes grass given APA was 83–102% of that given conventional N-P sources, and yield of Townsville stylo 60–70%. Curves for N and P uptakes over time were of sigmoidal form, with the steepest parts between days 40 and 120, suggesting a slow-release feature. However growth was depressed up to day 40, presumably by some toxic factor associated with the decomposition of the APA. This toxicity was avoided if some conventional fertilizer was applied with the APA.The other compound, the tetrasulphide of APA (APAS) had only limited fertilizer potential. Plants did absorb P and S at least from this compound, but Townsville stylo yield was only 32–38% of that with conventional fertilizers, and Rhodes grass yield not much greater than from control pots. The possible slow-release feature, and the toxic effect, did not occur with APAS.  相似文献   
55.
介绍农作物缺乏微量元素的诊断方法以及微量元素肥料合理施用的措施。  相似文献   
56.
Sugarcane response data from field experiments conducted between May 1979 and August 1981 on a sandy clay loam soil (Udic Haplustalf) of Coimbatore district, Tamil Nadu State, India were used in the present investigation. Soil () and fertilizer () nutrient efficiencies for the amount of fertilizer required for specified cane yield targets were computed from this data by three procedures, viz., conventional deduction procedure, Tamil Nadu Agricultural University Model I [TNAU Model I] and Model II [TNAU Model II].In the case of nitrogen, both TNAU Model I and TNAU Model II gave more realistic estimates of and than those determined by the conventional deduction procedure. The differences in the predicted amounts of fertilizer nitrogen required between these two models were well within the permissible limits of variation indicating that both these approaches can be followed for the amount of nitrogen required for specified yield targets.The Olsen's procedure for available phosphorus estimation was inadequate to explain the relationship between soil available phosphorus and sugarcane response as indicated by results obtained using the TNAU Model II. The incorporation of the term in this model caters for the actual situation in the field in respect of the relationship between soil and fertilizer phosphorus availabilities and phosphorus uptake by sugarcane proving usefulness of this model for assessing the amount of phosphorus required for specified cane yield targets.The results indicated that a considerable amount of potassium from the soil reserve was released into the soil available pool due to a priming effect. This fraction was preferentially absorbed by sugarcane compared to the fractions extracted by 0.1 N HNO3 as indicated by results obtained using the TNAU Model II. In this case too, the actual situation regarding the relationship between soil and fertilizer potassium availabilities and potassium uptake by sugarcane is catered for by this model proving its superiority over the other two procedures for assessing the amount of potassium required for specified yield targets.  相似文献   
57.
施氮量与基追比例对烟叶品质及氮肥利用率的影响   总被引:2,自引:0,他引:2  
通过3年的田间试验,研究了不同施氮量和基追比例对烟叶化学成分、感官质量及氮肥利用率等的影响。结果表明,降低施氮量增加了烟叶的总糖、还原糖含量和糖碱比,降低了总植物碱、总氮、钾含量及钾氯比,改善了烟叶感官质量;降低施氮量显著降低了氮素积累量、来自肥料和土壤的氮量,显著提高了氮肥利用率。相同施氮量,随追肥比例增加,2009和2012年度烟叶的总糖、还原糖含量及糖碱比先增加后降低,总植物碱、总氮含量先降低后增加;2010年烟叶总糖、还原糖含量及糖碱比降低,总植物碱和总氮含量提高。2009、2010年度感官质量分别以追肥比例为70%和50%的处理最佳;2012年度高施氮量以追肥比例为70%处理最佳,低施氮量以50%处理最好。增加追肥比例显著提高了氮肥利用率。通过3年研究发现,施氮量从90 kg/hm2降至45~60 kg/hm2,追肥比例增至50%~70%可改善烟叶感官质量及提高氮肥利用率。  相似文献   
58.
Fertilizers and eutrophication in southwestern Australia: Setting the scene   总被引:1,自引:0,他引:1  
An excess of plant nutrients has caused serious eutrophication in aquatic ecosystems of southwestern Australia manifested by excessive growth and accumulation of green and bluegreen algae. Phosphorus is generally the limiting nutrient for algal growth and phosphatic fertilizers applied to nutrient-deficient, leaching, sandy soils are the main source of P, supplemented by rural industry point sources. Nitrogen is the limiting nutrient in marine embayments with little drainage from the land. Measures to reduce the load of P delivered to drainage include basing fertilizer application rates on soil testing for P and the use of less soluble P fertilizers. Catchment management plans are being implemented with community involvement to reduce P loads and maintain agricultural production. This introductory paper reviews the history of eutrophication in southwestern Australia and of studies into its causes, principally in the large Peel-Harvey estuary. It briefly summarises other papers in this special issue concerned with different aspects of the problem: how to fertilize the land without causing eutrophication.  相似文献   
59.
A soil incubation and a greenhouse study on processing tomato were used to test the effects of soil temperature and the size and activity of the soil microbial biomass (SMB) on the degradation (mineralization) rate of a slow-release N fertilizer, methylene urea (MU), a condensation product of urea and formaldehyde. The mineralization rates of three MUs: Short (S), Medium (M), and Long (L) with different water solubilities were measured at two temperatures in a soil with low (fallow, F) and high (cover crop, CC) microbial activity. In the greenhouse study, the fate of fertilizer N was followed using 15N-urea and 15N-MU. The fertilizer N efficiency calculated for urea using the 15N mass balance approach was 93 and 85% compared with 65 and 67% for MU-S in F and CC soils, respectively. During six months of incubation, 52 and 63% of MU-S N was mineralized at 20 and 30 °C, respectively. The accumulated N data suggested that the degradation of all three MU types followed first-order reaction kinetics. The reaction rates were similar for all three MUs and increased with increasing temperature. However, fitting discrete, non-accumulated data revealed that MU mineralization is more complex and cannot be modeled with simple exponential decay equations. The size and activity of SMB did not affect the mineralization rate of MU-N under laboratory or greenhouse conditions. Interestingly, Activity Index (AI), defined as the slowly available pool of MU-N, was not a reliable indicator for the mineralization rate and plant availability of MU-N.  相似文献   
60.
粒状 NPK复合肥美国 TVA法之改良系利用美国 TVA的连续式滚筒氨化粒化机 ,设计加装一特殊埋床式反应器进行一系列的化学反应 ,释出大量的化学反应热 ,融化及溶解部分固体原料 ,改变原料物化性能 ,提供各种有利的造粒条件 ,促使氨化粒化机内的各种原料在最少的水分下 ,紧密结成坚硬浑圆 ,易于流动、搬运、储存 ,不结块的颗粒状 NPK复合肥。台湾引进美国 30年经验所研发出来的 TVA改良法具有如下特色 :(1)建厂成本低 ;(2 )原料选用宽广灵活 ,以致原料成本低 ;(3)干燥成品耗用燃料少 ;(4 )回流比小 ,用电量少 ;(5 )颗粒强硬、耐水 ,养分缓释持久 ;(6 )可生产多种不同配方的复合肥 ;(7)配方更改容易、迅速 ,适合少量多批次之生产  相似文献   
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