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101.
散装黑木耳容积林,重量轻,易破碎,是贮运的难题。本研究确定了黑木耳块的精加工工艺。通过软化,加压,干燥等项试验,分析了黑木耳的含水率,设备系统压力,环境温度等因素对黑木耳块加工的影响,确定了温度为10-25℃,含水率为20%-22%,压力为11MPa是工艺最佳参数,根据此工艺,又确定了液压专用设备。  相似文献   
102.
以两种性质不同的水稻土为材料,研究水稻和小麦在不同锌用量环境中的生长情况,以及锌在土壤、植株中积累的状况。结果如下:(1)土壤有效锌随施锌量的增加而增加,增加的幅度因土壤类型而异,黑粘土有效锌积累率为35.4%,是黄砂土的4倍。(2)水稻能在所设计的锌用量范围内正常生长。小麦耐锌能力因土壤类型而有很大差异,_黄砂土上的小麦表现出较强的耐锌能力,黑粘土施锌量在20mg/kg土时,小麦出现受害现象。(3)糙米含锌量为17.8~33.15ppm,麦粒含锌量17.02~66.72ppm,黑粘土Zn_(20)和Zn_(40)处理的麦粒中锌已超过自然含量范围。  相似文献   
103.
已知用生长激素(PST)处理美国的肥育猪可提高饲料报酬、生长速度和胴体的瘦肉率。由于中国猪比美国猪更肥一些,饲料报酬较低和生长较慢,因而设想用生长激素处理中国猪可能更有效。本试验在肥育期28天内用 PST 处理北京黑猪(由中国地方猪,约克夏和巴克夏杂交育成),在每天饲喂4次的个体饲养组(n=12,6头公猪和6头母猪)中,每天注射2毫克和4毫克 PST 的猪,其饲养报酬分别提高22.3%和30.6%(P<0.01),主要是提高了生长速度(分别比对照组快24.4%和30.2%)(P<0.01),而对饲料摄入量没有影响。每天注射 PST 2毫克(28天),群饲猪(6头/圈,4圈/处理组)得到了类似的结果:饲料报酬提高22.7%(P<0.01);生长速度提高25%(P<0.01)。屠宰分析的结果表明,每天注射2和4毫克 PST 的猪,最后肋膘厚率平均降低19.2%(P<0.01)。剥离分析半片胴体的结果表明,PST 处理猪的疫肉总量和瘦肉率分别提高21.4%和13%(P<0.01),而总脂肪量和脂肪率则分别降低16.7%(P<0.05)和22%(P<0.01)。胴体的化学分析获得类似结果。PST 处理猪的背最长肌的 ...  相似文献   
104.
本文用平衡透析法测定了黑熊血清蛋白与磺胺对甲氧嘧啶(SMD)的结合率(fb)为41.77±11.66(5.38~25.87)%.数据经Woolf作图法处理、直线回归后,得到结合参数βp和Kdp分别为:8.85±1.78μM/g,647.20±242.84μM/L.黑熊的fb均随药物浓度的增高而降低,高浓度的呈现饱和现象.不同浓度间的fb差异极显著(P<0.01),不同个体间的fb差异极显著(P<0.01).  相似文献   
105.
The objective of this study is to investigate the response of screening, and selection of novel indigenous AM fungal species and Azotobacter chroococcum strains for inoculating apple under different soil disinfestations and moisture conservation mulch practices for sustainable nursery management. Two local AM fungal species namely, Glomus fasciculatum (Thaxter sensu Gerdemann) and Glomus mosseae (Nicol. & Gerd.), and two strains of A. chroococcum viz., A. chroococcum strain-I (AZ1) and A. chroococcum strain-II (AZ2) were inoculated at nursery stage under soil solarization, chemical disinfestation and natural soil conditions at four different mulch materials namely, black plastic mulch (BPM), and organic mulches, i.e. grass mulch (GM); cover crops (CC); green manuring + clean cultivation (Gm + Cc). The comparative performance of the seedlings on the impact of local AM species and A. chroococcum strains on growth characteristics, microbial population, root colonization and leaf nutrient status was evaluated. The inoculation of seedlings to G. fasciculatum and AZ1 increased all growth characteristics (plant height, stem diameter, leaf area and total root length), microbial consortium of the rhizosphere soil and leaf N, P, K and Zn content in all those plots where soil solarization and black plastic mulching was used followed by chemical disinfestations and natural soil conditions at all other mulch types used. These findings suggested that the soil inoculation of G. fasciculatum and AZ1 strain to seeds and/or the saplings under soil solarization with black plastic mulch attained a desirable plant height and become ready for grafting which however saved a period of 1 year for nursery management compared to traditional nursery raising practice, and thus, it may be a viable and feasible approach to maintain soil productivity under nutrient limited soils for sustainable apple nursery production under temperate rain-fed conditions.  相似文献   
106.
Rice paddy soils are characterized by anoxic conditions, anaerobic carbon turnover, and significant emissions of the greenhouse gas methane. A main source for soil organic matter in paddy fields is the rice crop residue that is returned to fields if not burned. We investigated as an alternative treatment the amendment of rice paddies with rice residues that have been charred to black carbon. This treatment might avoid various negative side effects of traditional rice residue treatments. Although charred biomass is seen as almost recalcitrant, its impact on trace gas (CO2, CH4) production and emissions in paddy fields has not been studied. We quantified the degradation of black carbon produced from rice husks in four wetland soils in laboratory incubations. In two of the studied soils the addition of carbonised rice husks resulted in a transient increase in carbon mineralisation rates in comparison to control soils without organic matter addition. After almost three years, between 4.4% and 8.5% of the black carbon added was mineralised to CO2 under aerobic and anaerobic conditions, respectively. The addition of untreated rice husks resulted in a strong increase in carbon mineralisation rates and in the same time period 77%-100% of the added rice husks were mineralised aerobically and 31%-54% anaerobically. The 13C-signatures of respired CO2 gave a direct indication of black carbon mineralisation to CO2. In field trials we quantified the impact of rice husk black carbon or untreated rice husks on soil respiration and methane emissions. The application of black carbon had no significant effect on soil respiration but significantly enhanced methane emissions in the first rice crop season. The additional methane released accounted for only 0.14% of black carbon added. If the same amount of organic carbon was added as untreated rice husks, 34% of the applied carbon was released as CO2 and methane in the first season. Furthermore, the addition of fresh harvest residues to paddy fields resulted in a disproportionally high increase in methane emissions. Estimating the carbon budget of the different rice crop residue treatments indicated that charring of rice residues and adding the obtained black carbon to paddy fields instead of incorporating untreated harvest residues may reduce field methane emissions by as much as 80%. Hence, the production of black carbon from rice harvest residues could be a powerful strategy for mitigating greenhouse gas emissions from rice fields.  相似文献   
107.
The present study focuses on the microbial recalcitrance of pyrogenic organic material (PyOM) on a molecular scale. We performed microcosm incubation experiments using 13C- and 15N-enriched grass-derived PyOM mixed with a sub soil material taken from a Haplic Cambisol. Solid-state 13C and 15N NMR studies were conducted to elucidate the humification processes at different stages of PyOM degradation. The chemical structure of the remaining PyOM after incubation was clearly different from the initial pyrogenic material. The proportion of O-containing functional groups was increased, whereas that of aryl C and of N-containing heterocyclic structures had decreased, probably due to mineralisation and conversion to other C and N groups. After 20 months of incubation the aryl C loss reached up to 40% of the initial amount and up to 29% of the remaining PyOM C was assigned to carboxyl/carbonyl C and O-aryl C. These reactions alter the chemical and physical properties of the char residue and make it more available for further microbial attack but also for adsorption processes. Our study presents direct evidence for the degradation of N-heterocyclic domains in charred plant remains adding new aspects to the understanding of the N cycling in fire-affected ecosystems.  相似文献   
108.
汴杂9号是开封市蔬菜科学研究所以KS165为母本、KS28为父本选育的中熟、黑皮大果型西瓜新品种。植株根系发达,生长健壮,抗逆性强。全生育期约103d,果实发育期33d;主蔓第1雌花着生节位8~10节,雌花间隔5~6节。果实椭圆形,果皮纯黑有果粉,商品性好;瓜瓤鲜红色,中心可溶性固形物10.0%以上,边部8.0%左右,质脆爽口;皮厚1.1~1.2cm,韧性大,耐贮运;单果质量6~8kg,667m2产量3500kg左右。田间表现对枯萎病抗性强,较少发生病毒病。适宜河南、山东、河北、安徽、广西等省区种植。  相似文献   
109.
The cytological and biochemical response of the fungus Alternaria alternata to chitosan application in tomato fruits was evaluated. The research was developed in the following stages: microscopically to observe the degree of damage that chitosan causes over the conidia and hyphae of the fungus at the structural level and during the infection process in tomato tissue. Biochemically we tried to identify the elicitation of the phytoalexin rhisitin and other compounds involved in resistance. At the microscopic level, mycelium and conidia of chitosan-treated of A. alternata showed cell wall disintegration, plasma membrane retraction, cellular distortion, release of the apical portion of the conidia and lysis of fungal cells. Hyphae and conidia were susceptible to chitosan application. Infection always took place in chitosan treated and inoculated tomatoes and it was difficult to observe ultrastructural alterations due to chitosan application. The phytoalexin rhisitin was not isolated from any of the treatments but other compounds such as alkenes, fatty acids and vitamin E whose antimicrobial effects have been reported were detected. The elicitation of precursor compounds in the pathosystem A. alternata-tomato was more associated with the infection process than with the chitosan application. Further studies are necessary to confirm these findings.  相似文献   
110.
城市土壤有机碳和黑碳的含量特征与来源分析   总被引:29,自引:4,他引:29       下载免费PDF全文
何跃  张甘霖 《土壤学报》2006,43(2):177-182
由于城市化过程中人为活动的深刻影响,城市土壤的一些性质被强烈地改变。城市土壤有机质由于来源的多样性和受到不同程度人为活动的影响,其组成和分布特征表现出异质性和多样性。本研究以南京市为对象,研究了功能区之间土壤有机碳和黑碳含量的差异。与郊区土壤相比,城市土壤的有机碳含量普遍较高。通过对有机碳组成的分析发现其中稳定的黑碳含量较郊区土壤明显偏高,且在不同功能区之间呈现差异性,体现了人为影响过程和污染来源的差别。同时发现路边绿化带土壤正受到来自交通环境的强烈影响,其有机碳和黑碳含量与其他功能区存在显著差异。不同功能区之间因人为影响的差异,土壤中黑碳含量与有机碳含量的比值表现出明显的不同,可以指示黑碳的可能来源。城市土壤环境中黑碳可能构成了总有机碳中的很大部分,这与自然土壤有明显的差别。  相似文献   
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