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991.
Enzyme degradation method was adopted to prepare porous m-aramid/cellulose blend membranes with high air permeability, water absorbency and moisture permeability. This facile preparation process started by casting a blend membrane from a DMAc/LiCl solution containing m-aramid and cellulose. An enzyme was then used to degrade the cellulose in the blend membrane, resulting in porous structures. Five enzymes including cellulase, chitosanase, papain, lipase, and glucose oxidase, were evaluated and cellulase was found to be optimal. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the miscibility and the morphology of the m-aramid/cellulose blend membranes before and after degradation, respectively. The thermal stability of the blend membranes were characterized by thermogravimetric analysis (TGA). The properties including air permeability, water absorbency and moisture permeability of the m-aramid/cellulose blend membranes greatly improved after degradation as compared to those of the pure m-aramid. This paper provided a new approach to preparing novel textile materials with high comfortability.  相似文献   
992.
The wool fabrics were treated by ultraviolet (UV) radiation and then dyed with Camellia sinensis (L.) O. Ktze var. waldensae (S.Y.Hu) Chang (yellow-bud tea) extract using meta-mordant dyeing method. The results indicated that the hydrophilicity of wool fabrics was improved after UV radiation treatment, which was conducive in improving color performance for the meta-mordant dyeing with yellow-bud tea extract of wool fabrics. The optimal dyeing process was that the powdered extract (5.0 % o.w.f) and the CuSO4 (2.0 % o.w.f) were added to the dyeing liquor, the pH value was adjusted to 3.5-4.0 by HCOOH, the wool fabrics treated by UV radiation for 10 min and then were dyed at a bath ratio of 1:50 under 95 °C for 70 min. By means of three-factor quadratic current rotation revolving design (TQCRRD) method, the computation results of the mathematical equations and models indicated that UV radiation was the most important factor for meta-CuSO4 dyeing with yellow-bud tea extract for wool fabrics.  相似文献   
993.
Unmodified polyamide 6 commonly dyed with acid dyes, and has no flame-retarded properties. So they are flammable and can be easily stained by foods or drinks that contain acid dyes. However, the acid groups react with amino groups that existed at the end of PA6 chain while using cationic dyes. Thus, the acid dyes can be washed immediately. In this study, the flame retardant and cationic dyeable polyamide 6 (FRCD-PA6) modified with 5-sulfoisophthalic acid sodium (5-SSIPA) and melamine cyanurate (MCA) was successfully prepared by the two-step-melt polymerization method. Firstly, cationic dyeable polyamide 6 (CD-PA6) was prepared with sodium salt from 5-sulfoisphthalic acid. Secondly, melamine cyanurate, as an efficient flame retardant, was blended into the reaction. The chemical and crystalline structures of FRCDPA6 were characterized by the Fourier transform infrared spectroscopy (FT-IR) and wide angle X-ray diffraction (XRD). Their thermal properties were tested by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and morphology was analyzed by SEM, respectively. It had been measured to prove the dispersion of 5-SSIPA and MCA on polyamide 6 matrix. Incorporating with 5-SSIPA created more amorphous regions and rose up the dyeing rate easily, with a highest dyeing rate for about 96.79 %. The effect of varying MCA content on the composites showed more flame retardant and made better heat-resistance. Moreover, with the appropriate addition of MCA content, the limit oxygen index (LOI) reached up to 27, less smoking, no more black smoke, droplet phenomenon was slightly, and flame resistance had greatly improved. Because of the good synergy between 5-SSIPA and MCA, a kind of novel modified polyamide 6 which own both cationic dyeable and efficient flame retardant properties was born.  相似文献   
994.
基于DNA-SSR分析2015年度我国主推棉花杂交种纯度   总被引:3,自引:2,他引:1  
生产上棉种尤其是杂交种的真实性和纯度检测是1项大家十分关注的问题。2015年受7家棉种企业的委托,承担了棉种纯度鉴定工作,共接受样品95份,其中杂交种93份,亲本2份。利用SSR检测技术,发现2015年的纯度比2014年略提高,2年均明显优于2013年,表明近年杂交种的制种质量有明显的提高。检测工作开展以来,杂交种的做假行为得到了有效遏制。  相似文献   
995.
无人植保机在新疆棉田喷施脱叶剂测试结果评述   总被引:6,自引:3,他引:3  
无人植保机飞防技术作为一项适应现代植保需求的新型技术,将是传统植保方式的有益补充和革命性升级。为探明无人植保机喷施脱叶剂对棉花的脱叶效果及棉花品质的影响以及研究与筛选适合无人植保机喷洒棉花脱叶剂的喷洒参数和施药技术,国家航空植保科技创新联盟组织了多家联盟单位在新疆石河子开展了4种无人植保机喷施棉花脱叶剂的联合飞防试验。试验结果表明,经过2次施药后,4种无人植保机在设定施药范围内喷施脱叶剂,均能达到良好的脱叶效果;尤其按照每667 m2喷施1.5 L的药液,脱叶效果优良,药后棉铃吐絮率快速上升。测试结果还表明,无人植保机不同施药处理对处理区棉花的产量因子和纤维品质无明显影响。  相似文献   
996.
考虑风险价值的不确定性水资源优化配置   总被引:3,自引:2,他引:1  
保障区域农业用水的可持续发展,对水资源进行优化配置至关重要。由于粮食主产区水资源配置过程中存在许多不确定性因素,在追求最小用水成本时,也存在着较大的风险,因此该文以三江平原涵盖的七台河、佳木斯、双鸭山、鹤岗和鸡西5个重要粮食主产区为研究区域,以区间两阶段随机规划模型为基础,引入风险偏好,构建地表水和地下水优化配置模型。结果表明,双鸭山和鸡西的配水过程中地表水缺水量很大,主要开采利用地下水;佳木斯作为粮食生产面积较大的行政区,需要外来水进行补给;七台河和鹤岗的种植面积较小,综合考虑引水成本和粮食收益,引用较少的外来水来降低成本;最后得出不同来水水平下,各种风险偏好下水资源优化配置的最小成本的变化规律,即在低来水水平下,用水成本从344.2×108~355.4×108元增加到411.5×108~430.7×108元;在高来水水平下,总用水成本从422.5×108~435.3×108元降低到351.7×108~365.3×108元;在中来水水平时,总用水成本则呈现出先增加后减少的规律。该模型兼有区间两阶段和风险价值模型的特点,综合衡量成本和风险,可有效节约用水成本,并能增强水资源系统规避风险的能力,并以佳木斯2014年实际用水为例,计算得到相对误差在15%以内,较为真实地反映水资源优化配置过程中的不确定性和风险性,为提高水资源利用效率和区域水资源规划管理提供依据。  相似文献   
997.
Ammonia (NH3) volatilization is an important N loss pathway in intensive agriculture of the North China Plain (NCP). Simulation models can help to assess complex N and water processes of agricultural soil–crop systems. Four variations (Var) of a sub‐module for the deterministic, process‐based HERMES model were implemented ranging from simple empirical functions (Var 3 and 4) to process‐oriented approaches (Var 1 and 2) including the main processes of NH3 volatilization, urea hydrolysis, nitrification from ammonium‐based N fertilizer, and changes in soil solution pH. Ammonia volatilization, plant growth, and changes in ammonium and nitrate pools in the soil over several winter wheat–summer maize double‐crop rotations at three locations in the NCP were simulated. Results were calibrated with two data sets (Dongbeiwang 1, Shunyi) and validated using two data sets (Dongbeiwang 2, Quzhou). They showed that the ammonia volatilization sub‐module of the HERMES model worked well under the climatic and soil conditions of N China. Although the simpler equations, Var 3 and 4, showed lower deviations to observed volatilization across all sites and treatments with a mean absolute error (MAE) of 1.8 and 1.4 in % of applied N, respectively, compared to process‐oriented approaches, Var 1 and 2, with a MAE of 2.2 and 1.9 in % of applied N, respectively. Environmental conditions were reflected better by the process‐oriented approaches. Generally, simulation results were satisfying but simulated changes in topsoil pH need further verification with measurements.  相似文献   
998.
卵清蛋白(ovalbumin)基因在鸡基因组中只有一对等位基因,却能每天合成分泌多达2 g的蛋白,占据卵白蛋白质的50%以上,是外源基因载体表达调控构件的首选。该研究从输卵管特异性启动子方面着手,通过对卵清蛋白基因启动子的筛选优化,找出启动子增强因子的位置以及组织特异性区域。将卵清蛋白基因上游-922~-2 073和-2 801~-3 100区域平均分成12个长度约为150 bp的序列,分别插入到-921~+38序列的上游,成功构建12个系列表达载体,为进一步筛选短缩版优化启动子提供材料;卵清蛋白基因第一内含子区域截断成300 bp左右的迷你内含子序列,成功构建8个迷你内含子系列载体,为筛选优化的迷你内含子提供必要的材料;成功分离鸡输卵管上皮细胞并优化电转染条件,通过荧光素酶活性检测初步筛选出具有最强活性重组质粒pGL4 UP 1412和内含子重组质粒pGL4 mini intron 3,同时推断出若干包含增强子序列区域。  相似文献   
999.
选取撂荒田地为试验样地,以入侵植物豚草(Ambrosia artemisiifolia L.)为对象,以土著优势物种窃衣(Torilis scabra Thunb.)为参照,通过对入侵植物和土著植物根际土壤的采样分析,研究了入侵植物对入侵地土壤特性及土壤碳氮转化的影响。结果表明,与土著物种窃衣相比,豚草入侵使土壤有机质含量增加89.13%,全氮含量增加42.15%,铵态氮含量增加43.69%,硝态氮含量增加35.36%,微生物量碳增加52.08%,微生物量氮增加61.26%,氮净矿化速率增加1.41倍,氮净氨化速率增加206倍,但硝化速率和反硝化速率变化不明显。由此可见,豚草显著改变了入侵地土壤的理化特性,加速了土壤碳氮转化过程。  相似文献   
1000.
增氧对水培棉花生长的影响研究   总被引:1,自引:0,他引:1  
通过水培试验研究增氧对棉花生长的影响;试验设计3种增氧方式,分别为持续性增氧(Physical continuous oxygen,PCO)、间歇性增氧(Physical oxygen,PO),化学增氧(Chemical oxygen,CO),种棉花不增氧CK,不种棉花不增氧CK0;研究结果表明,不同增氧方式对营养液中溶解氧浓度都有不同程度的提高,表现为PCOPOCOCK;PCO处理对根体积、根系总吸收面积、根活性面积、根系生物量、株高、地上部生物量、氮和钾的吸收量的促进作用均达到显著水平,分别比CK增加了194.62%、261.89%、301.73%、57.15%、22.76%、38.03%、35.27%、84.78%;间歇性增氧PO处理对根系生物量、株高、地上部分生物量的促进作用显著,分别比CK高30.83%、15.65%、21.19%。通过以上结果表明,棉花对氧的需求敏感,不同增氧方式均能在一定程度上促进棉花生长,其中持续性增氧效果尤为突出,特别是对棉花生物量的积累,说明增氧可以提升棉花生长潜力。  相似文献   
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