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1.
基于计算机视觉识别技术的甘蔗种植机械化研究   总被引:1,自引:0,他引:1  
王盛  李明 《农机化研究》2017,(6):198-201
针对当前甘蔗种植机械化现状,优化机具设计,并应用计算机视觉识别技术,自动识别切种长度,预切甘蔗种,以便实现精密化、机械化的甘蔗种植。在计算机视觉识别技术支持下优化设计甘蔗种植设备,不仅可提升识别甘蔗茎节的正确率(提升80%),还可以提升甘蔗种植效益(提升20%),取得较好的经济效益。为此,设计了基于计算机视觉识别技术甘的蔗种植机械化设备,可提升甘蔗种植机械化水平,提高甘蔗预切种正确率,提升甘蔗机械化种植效益,产生积极影响。  相似文献   
2.
The cultivation of autumn sown sugar beet (winter beet) is supposed to result in a marked yield increase compared with spring sown sugar beet. Although the importance of the growth stage reached before winter for the survival of autumn sown sugar beet has already been shown, it is not clear to which extent osmotic and potentially frost protecting compounds may contribute to winter hardiness. The study thus aimed to analyse the acclimatization process of sugar beet to low temperatures and to identify compounds which are important for survival of frost. Field trials with autumn sown sugar beet were conducted at eleven environments in Germany from 2009/10 to 2012/13, which were accompanied by greenhouse experiments with controlled temperature regimes. In the field trials, the survival rates after winter varied from 0 % to 99 %, but only in four environments differences between the five genotypes occurred. During acclimatization, betaine, glutamine, proline and raffinose were markedly accumulated and osmolality was enhanced. In particular betaine, amino acids and osmolality showed a positive correlation to the survival rate and were thus identified as potentially frost protecting substances for sugar beet. In contrast, raffinose and proline seem to act rather as stress indicators as they were negatively related to survival. Possible frost protecting substances were identified which can be used in breeding to improve the winter hardiness of sugar beet.  相似文献   
3.
真空预冷技术在子芋冷藏保鲜上的应用研究   总被引:4,自引:3,他引:4  
将真空预冷技术配合塑料薄膜袋包装应用于冷藏保鲜子芋的预处理,研究不同的真空预冷处理工艺条件对子芋冷藏保鲜效果的影响,筛选最佳真空预冷工艺条件,并将保鲜效果同普通冷藏相比较。结果表明:采用真空室的真空度650 Pa,真空预冷终温4℃,预冷时间30 min进行真空预冷处理,并配合塑料薄膜袋包装的冷藏子芋比一般冷藏保鲜效果明显更好。表现在:冷藏30 d,外观饱满不皱皮,好果率提高19.5个百分点,失重率减少15.51个百分点,呼吸曲线明显下移,呼吸高峰推迟10 d出现,峰值减少20.2%。总糖保存率提高23.5个百分点。  相似文献   
4.
The effect of RUS, a major quantitative resistance (QR) factor inherited from Populus trichocarpa, was assessed in two Populus deltoides × P. trichocarpa F1 progenies against eight isolates of Melampsora larici‐populina, the causal agent of Eurasian poplar rust. Six isolates were identified on which RUS had no significant effect. The first RUS‐defeating isolate identified suggested a pre‐existing potential to overcome RUS in the pathogen’s populations. The P. deltoides genetic background made no difference either to the ability of a given isolate to overcome RUS or to the relative and absolute aggressiveness of the isolates. This study illustrates how extreme the isolate‐specificity of QR can be. It also yields insights into the relationship between size of uredinia and sporulation rate, discussing the epidemiological significance of spore production per mm2 uredinium.  相似文献   
5.
The efficacy of the anaesthetic agents benzocaine, metacaine (MS‐222), metomidate, 2‐phenoxyethanol, quinaldine and isoeugenol was studied in Atlantic halibut (Hippoglossus hippoglossus). Fish with an average body weight of 33 g were anaesthetized at 8 °C and fish with an average body weight of 1243 g were anaesthetized at 8 and 15 °C. Agents were tested individually and as combination anaesthesia comprising pre‐anaesthetic sedation, followed by anaesthesia. Induction and recovery times varied in relation to the body weight and water temperature. Large fish had longer induction times and shorter recovery times, and displayed reduced responsiveness to handling compared with small fish. A higher temperature resulted in shorter induction times, longer recovery times and increased responsiveness to handling. Lower dosages were used for all agents in combination anaesthesia. In small fish, this had no effect on the induction times but resulted in shorter recovery times and reduced responsiveness to handling. In large fish, combination anaesthesia resulted in shorter induction times whereas no uniform trend in recovery times and no differences in responsiveness to handling were observed. Neither individual agents nor combinations blocked all reflex reactions to external stimulation in all fish of any treatment group. MS‐222 and benzocaine, used separately or in combination anaesthesia, were the most effective agents in reducing reflex reactions.  相似文献   
6.
The bleeding efficiency of anaesthetized and exhausted Atlantic salmon was studied. Unbled fish were used as control groups for both treatments. Several analytical methods (computer vision, Minolta Chroma Meter, transflectance spectroscopy, haemoglobin iron and visual assessment of smoked fillets) were used to evaluate colour or residual blood contents of pre‐rigor and smoked fillets. In all cases, the amount of residual blood in the fillets was modest and blood was not considered a quality problem in terms of fillet appearance. Perimortem stress did not affect residual blood contents of pre‐rigor fillets. Only salting and smoking had a significant effect on filet colour. The low levels of residual blood was partly attributed to filleting shortly after killing allowing washing before the blood had time to coagulate. In addition, a computer vision method was developed for automated blood inspection of the body cavity after gutting and washing. A classifier (‘no blood’ or ‘blood present’) based on linear discriminant analysis was tested and the classification accuracy was over 90% as evaluated with the leave‐one‐out method.  相似文献   
7.
不同处理对甜樱桃近生物冰点贮藏效果研究   总被引:9,自引:2,他引:7  
研究了甜樱桃品种‘拉宾斯’(Prunus aviumL.cv.Lapins)经冰水预冷、0℃强制通风预冷以及15%CO2短时处理后在近生物冰点(-1.0±0.5℃)贮藏条件下果实的风味品质、腐烂率和贮藏过程中的果汁冰点变化。结果表明,近生物冰点贮藏条件下,除对照外,各处理均能有效保持果实硬度(0.6~0.7 kg)、可溶性固形物含量(13%~14%)、可滴定酸含量(0.9%~0.6%)和果皮花青苷含量(70~100 U);贮藏60 d,冰水预冷和冰水预冷+CO2处理果实腐烂率分别达到25.5%和18.4%,而对照和强制通风预冷则只有7.7%和3.6%,其中以强制通风预冷+CO2短时处理+聚乙烯袋效果最佳,在贮藏过程中未出现果实腐烂现象;除对照外,各处理在贮藏过程中的果汁冰点一直维持在-1.5℃左右,变化不大。说明近生物冰点贮藏技术能最大程度的延长甜樱桃的贮藏期。  相似文献   
8.
电站锅炉沼气点火装置的研究与设计   总被引:1,自引:0,他引:1  
详细阐述了电站锅炉沼气点火装置的喷嘴,引射器及烧嘴的设计计算与稳定火焰的方法。应用结果表明,该点火装置火焰温度高,适应性强,使用经济,操作方便,在电站锅炉无油,少油点火方面有着广阔的应用前景。  相似文献   
9.
桃的采收成熟度与果实的耐藏性有较密切的关系。在7~8成熟时的绿熟期采收,经贮藏后果面新鲜,果实硬而脆,褐变和腐烂少;采收过晚则果实易软化,容易褐变和腐烂。采前1个月用100mg/kgGA3处理有利于提高桃果实的耐藏性,贮藏后处理果的硬度比对照高1倍;采前1~2d用500mg/kg朴海因处理大久保、京玉和燕红桃,贮藏好果率分别增加22.8%,22.9%和18.3%;采前用混合液(GA350mg/kg,2,4-D50mg/kg,多菌灵2000倍)处理可减慢桃果实在贮藏期间的生理代谢,并能较好地保持品质,腐烂和褐变指数分别比对照降低7.7%和4.0%。  相似文献   
10.
通过对高锰酸钾复合药剂、粉末活性炭、预氯化工艺的对比及它们之间的联用组合工艺的试验研究 ,证明高锰酸钾复合药剂与粉末活性炭联用组合对微污染水的除色、除味、降低出水浊度效果明显。从而为老水厂寻找了一种简便易行、经济有效的去污染手段。  相似文献   
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