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91.
本试验收集引进了7个果蔗品种进行品比鉴定,各品种间出苗、分蘖、成茎、节间性状、产量性状、田间锤度及食用品质均表现出较大差异。试验表明:紫皮果蔗中,句紫和溧紫综合性状表现较优,适宜在本地区种植;青皮果蔗中,以海青表现较好,可根据当地消费习惯,适当示范种植。  相似文献   
92.
【目的】明确供试5种杀菌剂对甘蔗黑穗病菌的田间防治效果和安全性,为甘蔗黑穗病综合防控提供科学依据。【方法】采用药剂或药泥浸泡甘蔗种茎处理、甘蔗收砍后药液喷淋蔗桩处理等方法进行5种杀菌剂(250 g/L嘧菌酯悬浮剂、250 g/L苯醚甲环唑乳油、300 g/L苯醚甲环唑·丙环唑乳油、325 g/L苯醚甲环唑·嘧菌酯悬浮剂和250 g/L丙环唑乳油)对新植蔗、宿根蔗黑穗病的防治试验。【结果】在新植蔗试验中,播种后240 d调查,250 g/L丙环唑乳油250mg/kg、250 g/L苯醚甲环唑乳油125 mg/kg、250 g/L嘧菌酯悬浮剂166.7 mg/kg、300 g/L苯醚甲环唑·丙环唑乳油200mg/kg和325 g/L苯醚甲环唑·嘧菌酯悬浮剂216.7 mg/kg处理在网室无病试验地对黑穗病的防效均达90.00%以上,在有病试验地的防效分别为73.37%、80.63%、83.43%、84.06%和87.61%,250 g/L苯醚甲环唑乳油125 mg/kg药泥浸泡甘蔗种茎处理的防效为89.57%,显著好于单纯药液处理。在宿根蔗黑穗病防治试验中,用上述药剂在甘蔗砍收后次日喷淋蔗桩,于甘蔗分蘖期调查的防效分别为75.51%、81.90%、81.53%、83.61%和85.83%。5种杀菌剂对甘蔗生长均安全。【结论】5种参试杀菌剂对甘蔗黑穗病均有良好的防治效果,可作为防治甘蔗黑穗病的药剂在生产上推广应用。  相似文献   
93.
Responding to the challenges posed by global warming, peak oil and biofuels will require a paradigm shift in the practice of agriculture and in the role of live stock within the farming system. Farming systems should aim at maximizing plant biomass production from locally available diversified resources, processing of the biomass on farm to provide food, feed and energy and recycling of all waste materials. The approach that is the subject of this paper is that the generation of electricity can be a by-product of food/feed production. The concept is the fractionation of biomass into inedible cell wall material that can be converted to an inflammable gas by gasification, the gas in turn being the source of fuel for internal combustion engines driving electrical generators. The cell contents and related structures such as tree leaves are used as human food or animal feed. As well as providing food and feed the model is highly appropriate for decentralized small scale production of electricity in rural areas. It also offers opportunities for sequestration of carbon in the form of biochar the solid residue remaining after gasification of the biomass.  相似文献   
94.
为了实现排种的均匀稳定,针对预切种式宿根蔗补种的难题,设计了一种宿根蔗补种机均匀排种控制系统,由辊耙、理蔗压板、种箱以及电控系统等组成。通过运用EDEM对排种机构的排种过程进行仿真分析及虚拟试验,探讨了系统主要工作参数对排种性能的影响,对机构进行了优化设计。通过单因素试验及Box-Behnken响应面正交试验,研究了辊耙角速度、理蔗压板压力、种箱内蔗种数量、理蔗压板活动角对排种均匀度的影响规律,建立了排种机构排种性能的响应面方程,构建了排种系统参数调节的控制模型和控制算法。以种箱内蔗种数量作为控制器输入量,控制器通过自动调整辊耙角速度和理蔗压板压力来控制排种系统排种过程的均匀性。试验结果表明,应用参数自调节排种控制系统进行排种作业时,排种合格率为94.44%,与未应用参数自调节的排种系统相比提高8.88个百分点;排种均匀度为0.46段2。研究可为提高甘蔗宿根补种的均匀性及稳定性提供技术支持。  相似文献   
95.
《African Zoology》2013,48(2):311-320
The greater cane rat is a recently domesticated monogastric herbivore, and the importance of the caecum in the functioning of its digestive tract has frequently been mentioned. However, no data are available on caecal fermentative activity of this animal and research on the digestive physiology was only performed in adult animals. The present work was initiated to describe some parameters of the digestive tract anatomy and to study caecal fermentation of the growing cane rat. Thirty 40-day-old weaned cane rats were used in this experiment. Six of them were immediately euthanased and 12 were housed in a collective pen for gastrointestinal tract (GIT) parameters measurements. Twelve others were kept in individual cages to record growth and food intake. Captive cane rats received a pelleted diet containing 12.5% of crude protein and 16.7% of lignocellulose. Six of the 12 collectively housed animals were euthanased on day 82 and a further six on day 103. The growth rate increased with age (P < 0.01) with a linear growth curve (P < 0.001) while the feed intake (g/kg body weight) did not vary (P > 0.05). The caecum represented the largest compartment of the digestive tract constituting more than 40% of total GIT contents. Acetate was the most abundant short-chain fatty acid with more than 70% of the total, followed by propionate (less than 25%) and butyrate (around 5%). Short-chain fatty acid profiles varied with age: when age increased, the acetate proportion increased (P < 0.01), the propionate proportion decreased (P < 0.001) and the butyrate proportion remained unchanged (P > 0.05). The propionate/butyrate ratio showed a decrease with an increase in age (P = 0.05). Ammonia concentrations did not vary with age (P > 0.05). It is concluded that the caecum is an important site of fermentation in the growing cane rat.  相似文献   
96.
甘蔗黑穗病菌粗毒素对甘蔗愈伤组织的影响   总被引:2,自引:0,他引:2  
甘蔗黑穗病菌(Ustiago Seitamimea Syd)的粗毒素处理三个甘蔗品种(新台糖10号、CP65/375和桂糖12号)的岔伤组织。接种粗毒素培养后,结果表明:甘蔗愈伤组织过氧化物酶活性的变化情况与品种的抗病性有关。  相似文献   
97.
BACKGROUND: A major global challenge is to provide agricultural production systems that are able to sustain growing demands for food, feed, fibre and renewable raw materials without exacerbating climate change. Detailed and reliable data on the CO2 balance of different agricultural management activities and inputs as a basis to quantify carbon footprints of agriculture are still lacking. This study aims to fill this gap further by quantifying the net balance of emitted and assimilated CO2 due to the application of crop protection treatments on the farm, and by assessing their partial contribution to GHG emissions and mitigation in agriculture. The study focuses on key agricultural crops including wheat, corn, oilseeds and sugar crops. RESULTS: The final CO2 balance, considering GHG emissions due to on‐farm CPP treatment in comparison with CO2 storage in additional biomass, CO2 protected with respect to agrotechnical inputs and land inputs and CO2 saved with respect to associated global land use changes, is positive and may reach multiples of up to nearly 2000. CONCLUSION: The results highlight the importance of the positive yield effects of the CPP programme applications on the farm, resulting in additional assimilated biomass at the farm level and less land use changes at the global level, and thus lower pressure on environmentally important indicators of overall agricultural sustainability. Copyright © 2012 Society of Chemical Industry  相似文献   
98.
基于Zeta电位法分析新生亚硫酸钙对蔗汁胶体的吸附特性   总被引:1,自引:0,他引:1  
【目的】从Zeta电位的角度考察新生亚硫酸钙对蔗汁胶体的吸附规律,为适时监测和优化制糖澄清工艺提供新途径。【方法】通过模拟亚硫酸法制糖澄清工艺,探讨新生亚硫酸钙吸附蔗汁胶体过程中Zeta电位的变化规律及其与新生亚硫酸钙对蔗汁胶体吸附量(Qe)的相关性。【结果】随着p H和胶体浓度的升高,Zeta电位和新生亚硫酸钙对蔗汁胶体的Qe逐渐增大;随着Zeta电位的增大,新生亚硫酸钙对蔗汁胶体的Qe也逐渐增加。新生亚硫酸钙对胶体的吸附等温线采用Freundlich模型拟合时,其拟合参数R^2大于Langmuir模型的拟合参数R^2。【结论】新生亚硫酸钙对蔗汁胶体吸附特性更符合Freundlich等温吸附模型,且新生亚硫酸钙对蔗汁胶体的Qe与其Zeta电位呈正相关。  相似文献   
99.
从海南7个市县的甘蔗主产区采集了20份甘蔗根际土样,采用Gendeman的湿筛倾析-糖液离心法分离土样中的孢子,依据形态学方法初步鉴定出6属31种丛枝菌根真菌,包括19个确定种,12个待确定种;其中,无梗囊霉属(Acaulospora)有11个种,已确定7个种;原囊霉属(Archaeospora)有1个确定种;球囊霉属(Glomus)有12个种,已确定5个种;巨孢囊霉属(Gigaspora)有2个确定种;盾巨孢囊霉属(Scutellospora)有4个确定种;多孢囊霉属(Diversispora)有1个待定种.对已确定的19个种的菌根真菌进行了形态描述.孢子分离结果表明:球囊霉属(Glomus)分离频率最高,是海南甘蔗根际丛枝菌根真菌的优势属;悬钩子球囊霉(G.rubiforme)分离频率最高,是31个种中的优势种.  相似文献   
100.
为了解过氧化物酶(POD)和酯酶(EST)同工酶在果蔗生长中的变化规律,本研究选择不同的取样时期和植株不同器官,对8个果蔗品种利用垂直平板聚丙烯酰胺电泳得出的叶片、根组织不同生育时期POD、EST同工酶酶谱进行聚类分析,并检测其相关性。结果表明:(1)不同品种间同工酶谱的遗传相似系数存在差异,特别是外引黑皮果蔗(Badila)与中国地方品种之间存在着一定的遗传差异;(2)不同生育时期叶片或根部的POD同工酶和EST同工酶酶谱的聚类图都存在着差异;(3)叶片中的POD、EST酶谱在各个生育时期均达到极显著相关。说明叶片是这两种酶基因表达的最重要活性部位,因此叶片可以作为同工酶分析较为稳定和适宜的采样部位。  相似文献   
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