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61.
Quinaldine and phenoxyethanol, two commonly used fish anesthetics, reduced the intensity of a chemically induced fright response in a marine goby. MS-222, an anesthetic that has been indicated as harmful to fish olfaction, had no significant effect. Understanding these effects must await further study, but it is clear that caution should be exercised. One should definitely not use quinaldine or phenoxyethanol instead of MS-222 in an effort to avoid harmful effects.  相似文献   
62.
Olfaction is crucial in many insects for critical behaviors, including those regulating survival and reproduction. Insect odorant-binding proteins (OBPs) function in the first step of the olfactory system and play an essential role in the perception of odorants, such as pheromones and host chemicals. The oriental fruit fly, Bactrocera dorsalis, is a destructive fruit-eating pest, due to its wide host range of up to 250 different types of fruits and vegetables, and this fly causes severe economic damage to the fruit and vegetable industry. However, OBP genes have not been largely identified in B. dorsalis. Based on our previously constructed B. dorsalis cDNA library, ten OBP genes were identified in B. dorsalis for the first time. A phylogenetic tree was generated to show the relationships among the 10 OBPs of B. dorsalis to OBP sequences of two other Dipteran species, including Drosophila melanogaster and the mosquito Anopheles gambiae. The expression profiles of the ten OBPs in different tissues (heads, thoraxes, abdomens, legs, wings, male antennae and female antenna) of the mated adults were analyzed by real-time PCR. The results showed that nine of them are highly expressed in the antenna of both sexes, except BdorOBP7. Four OBPs (BdorOBP1, BdorOBP4, BdorOBP8, and BdorOBP10) are also enriched in the abdomen, and BdorOBP7 is specifically expressed in leg, indicating that it may function in other biological processes. This work will provide insight into the roles of OBPs in chemoreception and help develop new pest-control strategies.  相似文献   
63.
It has become difficult to find a matching perfume. An overwhelming number of 300 new perfumes launch each year, and marketing campaigns target pre-defined groups based on gender, age or income rather than on individual preferences. Recent evidence for a genetic basis of perfume preferences, however, could be the starting point for a novel population genetic approach to better match perfumes with people's preferences. With a total of 116 participants genotyped for alleles of three loci of the major histocompatibility complex (MHC), the aim of this study was to test whether common MHC alleles could be used as genetic markers to segment a given population into preference types. Significant deviations from random expectations for a set of 10 common perfume ingredients indicate how such segmentation could be achieved. In addition, preference patterns of participants confronted with images that contained a sexual communication context significantly differed in their ratings for some of the scents compared with participants confronted with images of perfume bottles. This strongly supports the assumption that genetically correlated perfume preferences evolved in the context of sexual communication. The results are discussed in the light of perfume customization.  相似文献   
64.
人工嗅觉系统设计初步   总被引:3,自引:0,他引:3  
采用纳米薄膜气体传感器构成传感器阵列,采用分压式取样电路测量传感器在气氛中电阻的响应曲线。提出“气味谱”的概念,用误差反传神经网络和自组织特征映射神经网络(SOM)进行学习训练和识别,结果表明SOM网络更接近于人类对气味的认知过程,是人工嗅觉系统较为理想的算法。玻璃基片等离子溅射镀膜方法是制造人工嗅觉所需的大规模气体传感器阵列的有效方法。  相似文献   
65.
Dopaminergic modulation affects odor detection thresholds and olfactory discrimination capabilities in rats. The authors show that dopamine D? receptor modulation affects odor discrimination capabilities in a manner similar to the modulation of stimulus intensity. Performance in a simultaneous odor discrimination task was systematically altered by manipulations of both odorant concentration and D? receptor activation (agonist quinpirole, 0.025-0.5 mg/kg; antagonist spiperone, 0.5 mg/kg). Rats' discrimination performance systematically improved at higher odor concentrations. Blockade of D? receptors improved performance equivalent to increasing odor concentration by 2 log units, whereas activation of D? receptors reduced odor discrimination performance in a dose-dependent manner. Bulbar dopamine release may serve a gain control function in the olfactory system, optimizing its sensitivity to changes in the chemosensory environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
Age-appropriate tasks were used to assess 3- to 8-year-old children's liking, identification, and preference for a variety of odors, including that of exhaled cigarette smoke. Children whose parents smoke took longer to decide whether they liked the cigarette odor and were significantly more likely to prefer the odor of cigarette to the neutral and unfamiliar odor of green tea compared with children of nonsmokers. Among children of smokers, relative preferences for the cigarette odor were related to maternal mood disturbance and depression scores. These findings suggest that some early learning about cigarette smoke odor is based on sensory experiences at home and anchors it to the emotional context in which their mothers smoke. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
In order to test the hypothesis that commensal bacteria influence the urinary odors of individuality, we collected urine from PVG and PVG.R1 male rats born by cesarian section and reared in a germ-free environment. Using the habituation-dishabituation test with PVG.RT1 u and Lister hooded rats as subjects, we found that urine from the germ-free rats was not discriminated, while urine from conventionally housed rats of the same strains could be discriminated (experiment 1). When the germ-free rats were moved to a conventional animal house after recolonization with commensural flora and their urine collected, it was discriminated, indicating an essential role of bacteria in determining the unique urinary odors of MHC-congenic rats (experiment 2). The conventionally housed and germ-free rats did not differ in the amount of class I antigen in their urine (experiment 3). Finally, urines of PVG and PVG.R1 donors inoculated with a defined and highly restricted flora to render them specific-pathogen-free (SPF) could not be discriminated. Urine from SPF donors moved to a conventional animal house could be discriminated (experiment 4). These results indicate that commensal bacteria are essential for the production of the unique individual odor of the urine of MHC-congenic strains of rats.  相似文献   
68.
Mouse urine contains substantial quantities of a family of proteins (MUPs) that are members of the lipocalycin family of proteins and that are potentially capable of binding hydrophobic molecules. We have used gas chromatography-mass spectrometry (GC-MS) to characterize two ligands associated with the MUPs, a thiazole and a brevicomin derivative. Previous work has suggested a role for these two ligands as androgen-dependent pheromones. In urine, nearly all of these ligands are protein bound and fractionation of MUPs on Mono-Q anion exchange chromatography indicated some specificity of ligand binding by the MUP subclasses.  相似文献   
69.
The attraction of the red turpentine beetle,Dendroctonus valens, to the resin volatiles of its host,Pinus ponderosa, is elicited by three chiral monoterpenes. In field assays response was greatest to (S)-(–)--pinene; 92% (S)-(–)--pinene found inP ponderosa resin was not attractive. However, 75% (R)-(+)--pinene, which occurs inPinus lambertiana, a sympatric host ofD. valens, was attractive. (S)-(–)--Pinene interrupted response to (R)-(+)--pinene. (S)-(+)-3-Carene from both hosts was attractive at the (R)-(+)--pinene level. Three sympatric coniferous nonhosts each have the same attractive monoterpenes but produce less resin. These studies demonstrate the importance of chirality of host compounds in the host finding behavior of this bark beetle.  相似文献   
70.
时变流场环境中机器人跟踪气味烟羽方法   总被引:5,自引:0,他引:5       下载免费PDF全文
李吉功  孟庆浩  李飞  蒋萍  曾明 《自动化学报》2009,35(10):1327-1333
机器人对气味烟羽的可靠跟踪是实现气味源定位的关键. 本文主要针对实际时变流场环境中的机器人跟踪气味烟羽问题进行研究. 文中在机器人测得气味时估计气味包的最大可能路径, 在此基础上结合流向信息, 规划搜寻路径并使机器人沿此路径运动以跟踪气味烟羽. 考虑到气味浓度场的时变特性以及可能存在的基本浓度, 采用浓度相对变化量表征气味信息. 室内时变流场环境实验表明, 使用本文所提方法的机器人可实时、有效地跟踪烟羽并趋向气味源.  相似文献   
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