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51.
A piezoelectric sprayer was recently developed for precision release of odor stimuli in olfactory research. The device replaces conventional dispensers used to release semiochemicals in studies of moth flight toward odor sources. However, the device generates high-frequency sounds in the range that some moths can hear. Ultrasound from the standard set-up sprayer had a considerable impact on flight behavior of the silver Y moth, Autographa gamma, tested in a flight tunnel. It was affected at all behavioral stages when the dispenser was driven at 120 kHz. Only 5% of the moths reached the source when exposed to 120-kHz sound from the dispenser compared to 65% in the control group without sound. The proportion taking flight was also reduced. Hearing threshold curves obtained electrophysiologically revealed that moths were sensitive to the frequency range at which the sprayer was operated and that sound intensity from the sprayer was up to 40 dB above the moths' electrophysiological hearing threshold. The audiogram for A. gamma was similar to audiograms obtained for other noctuids. Hearing sensitivity was highest at around 15 kHz, where the threshold was 35 dB SPL (sound pressure level). The threshold increased with frequency up to 94 dB SPL at 160 kHz. We improved the sprayer to operate at 300 kHz, which is beyond the hearing ability of most insects with ears. At this high frequency, the moths' sensitivity to ultrasound is reduced considerably, and we did not observe any effect on flight behavior compared to a control group without sound. Accordingly, this new piezoelectric sprayer can be used with ultrasound-sensitive insects and insensitive insects alike.  相似文献   
52.
The basolateral (BLA) and medial nucleus (MeA) of the amygdala participate in the modulation of unconditioned fear induced by predator odor. However, the specific role of these amygdalar nuclei in predator odor-induced fear memory is not known. Therefore, fiber-sparing lesions or temporary inactivation of the BLA or MeA were made either prior to or after exposure to cat odor, and conditioned contextual fear behavior was examined the next day. BLA and MeA lesions produced significant reductions in cat odor-induced unconditioned and conditioned fear-related behavior. In addition, temporary pharmacological neural inactivation methods occurring after exposure to cat odor revealed subtle behavioral alterations indicative of a role of the BLA in fear memory consolidation but not memory retrieval. In contrast, the MeA appears to play a specific role in retrieval but not consolidation. Results show that the BLA participates in the conditioned and unconditioned cat odor stimulus association that underlies fear memory, underscore a novel role of the MeA in predator odor contextual conditioning, and demonstrate different roles of the BLA and MeA in modulating consolidation and retrieval of predator odor fear memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
发酵法在淡水鱼鱼糜脱腥中的应用研究   总被引:2,自引:0,他引:2  
利用活性干酵母发酵法对淡水鱼鱼糜进行脱腥,选择接种量、温度、时间、和pH四因素进行正交试验,以感官评定结果和三甲胺含量作为评价指标,优化了该法脱腥的最佳工艺条件。结果表明,当酵母接种量为2.00%、pH6.65、温度35℃下加热30min,脱腥效果最好,由此加工制成的鱼糜制品产品品质良好。  相似文献   
54.
55.
郑桂华  张晓霞  李艳萍 《酿酒》2008,35(3):80-81
低度白酒的生产,有利于节约粮食、降低能耗;有利于饮用者的身体健康;有利于与国际市场接轨,提高生产效率、提高产品市场占有率、提高产品的产量与质量,兼香型白酒是建国后创新的两大香型之一,低度兼香型东北王酒的生产与发展,使企业走出一条健康、稳定、可持续发展之路。  相似文献   
56.
Recent observations on the occurrence of fishy flavour in bacon   总被引:1,自引:0,他引:1  
An examination of reject bacon samples supplied directly from a factory showed that some samples described by a sensory panel as oily and fishy contained significantly higher levels of long chain polyunsaturated fatty acids (PUFA) in their fat than normal samples. When bacon samples obtained from retail outlets were similarly analysed and then subjected to sensory assessment, those found to contain long chain PUFA were given significantly higher scores for oily and fishy flavour. Observations on the fatty acid composition of fishy bacon samples as compared to non-fishy ones and further investigation into the diets of pigs producing suspect carcasses led to the conclusion that too high a content of fish products in the diet was the main cause of the problem. Contrary to what had been believed, fresh non-fishy bacon samples did not develop fishy flavour after storage at ?20°C for 15 weeks. Perceived fishiness was not related to total copper content as determined by atomic absorption spectroscopy.  相似文献   
57.
The present study investigated the role of endogenous opioids in the expression of defensive behaviors (DBs) and the suppression of cell proliferation (CP) in the dentate gyrus (DG) induced by exposure to predator odor, trimethyl thiazoline (TMT). Adult male rats were injected with either naltrexone (an opioid antagonist, 5 mg/kg) or saline 30 min before exposure to either TMT or a control odor. Behavior was scored for the first 15 min of odor exposure. Bromodeoxyuridine (BrdU, 200 mg/kg) was then injected, and the rats were perfused 1 hr later. Exposure to TMT increased the expression of DBs and suppressed the number of proliferating cells in the DG. Pretreatment with naltrexone attenuated the effects of TMT on DB expression but did not attenuate the effects of TMT on CP. In addition, naltrexone administration suppressed CP in the absence of TMT. These results demonstrate a dissociation between DBs and regulation of CP in the DG. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
苜蓿浓缩叶蛋白脱色、脱腥工艺研究   总被引:2,自引:0,他引:2       下载免费PDF全文
通过试剂筛选,以无水乙醇为漫提剂,研究了不同条件对苜蓿浓缩叶蛋白脱色、脱腥的影响,通过正交试验得出了脱色的最佳工艺条件:液固体积质量比6mL:1g,浸提温度85℃;浸提时间4h;浸提级数3级。此工艺参数的确定为苜蓿叶蛋白的脱色、脱腥提供了新方法,提高了苜蓿浓缩叶蛋白在食品中应用的可行性。  相似文献   
59.
以苹果、海带为主要原料,研制了一种复合饮料。着重研究了海带的浸提、脱腥以及防止苹果汁褐变的方法。结果表明:海带汁提取时加入10倍的水、柠檬酸用量为0.5%、常压煮沸30min,以菊花茶除腥,按苹果汁:海带汁7:3配合,制成的复合饮料风味较好。  相似文献   
60.
采用顶空固相微萃取气相色谱串联质谱法(HS-SPME-GC-MS/MS)对5种莲蓉馅料的挥发性物质进行研究,共检测到醇类(7.07%~9.72%)2种,醛类(18.38%~36.45%)7种,酯类(9.97%~23.88%)6种,吡嗪类(19.07%~29.38%)4种,烷烃类(1.31%~5.29%)3种,呋喃类(1.53%~4.88%)2种,酮类(2.78%~3.62%)2种,萜类(0%~10.82%)1种,噻吩类(0.04%~0.31%)1种,其他类(11.11%~16.21%)1种。通过PLS-DA模型与方差分析法筛选出不同莲蓉馅料的主要差异物质为糠醛、E,E-2,4-癸二烯醛、(±)-3-蒈烯-2,5-二酮、苯甲醛、正壬醛、2,6-二甲基吡嗪、3-甲基苯甲醛和十四烷。根据相对香气活度值(ROAV)评判莲蓉馅料的主要挥发性风味物质,其贡献程度大小依次为E,E-2,4-癸二烯醛、辛酸乙酯、2-乙酰基噻吩、正壬醛、己醛、乙酸苯乙酯和苯乙醇。综合不同莲蓉馅料挥发性成分的主要差异物质和风味贡献程度分析得出,E,E-2,4-癸二烯醛、正壬醛和苯甲醛的相对含量是影响莲蓉馅料呈香的主要因素。该研究结果揭示了莲蓉馅料的风味轮廓,为其品质评价与标准化生产提供理论依据。  相似文献   
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