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31.
Using a simple two-choice bioassay and video analysis of individual locomotory tracks, it was determined that a preference for young-bee hosts over old-bee hosts in female honeybee tracheal mites,Acarapis woodi (Rennie), is chemically mediated. When presented with a choice of cuticular extracts from 5-day-old and <1-day-old adult bees, mites showed a significant preference for the young-bee extract in three of four bee colony sources. This discrimination was due apparently to a greater positive response elicited by the young-bee extract rather than a deterrent effect of old-bee extract, as the extract of old bees evoked a significantly higher response than a hexane control. A bioassay of silica-gel fractions of young-bee extract indicated that cuticular hydrocarbons alone were responsible for tracheal mite response. Further fractionation of a hydrocarbon fraction by argentation chromatography demonstrated that both saturated and unsaturated hydrocarbons were involved in the mite response, but when presented in opposition, mites showed a stronger response to the saturated than to the unsaturated components. Mites placed in zones treated with cuticular extract of young bees exhibited higher angular velocities than those placed on hexane, causing them to remain in the extract-treated zones for extended periods. These results point to a possible control strategy whereby migration of tracheal mites to young-bee hosts could be disrupted by artificially altering the chemical profile of the honeybee cuticle. 相似文献
32.
From Robinia pseudoacacia L. nectar to Acacia monofloral honey: biochemical changes and variation of biological properties 下载免费PDF全文
33.
M. H. Pham-Delegue P. Etievant E. Guichard R. Marilleau Ph. Douault J. Chauffaille C. Masson 《Journal of chemical ecology》1990,16(11):3053-3065
We present a review of work on the plant chemicals involved in the honeybee-sunflower model system. Combined behavioral and chemical analyses were conducted under natural and controlled conditions. First the distribution of forager bees' visits on two pairs of sunflower genotypes producing a different level of hybrid seed yield was recorded under pollen-proof tunnels. Mirasol parental lines producing high seed yields were visited at random, whereas forager bees visited preferentially the female parental line of Marianne, resulting in low seed yield. Nectar samples collected on the genotypes were analyzed by gas chromatography. Fructose, glucose, and sucrose were identified. Parental lines of Mirasol showed similar sugar profiles, whereas the female line of Marianne contained higher amounts of sucrose than the male line. We assume that the bees' preferences between genotypes might rely on differences in the sugar composition of floral nectars, especially in the amount of sucrose. Aromas from headspace collection were compared between pairs and periodically during the flowering period. Of the 144 components indexed for Marianne lines and 136 components for Mirasol lines, 17 of the components for Marianne lines and 18 for Mirasol lines differed significantly according to flowering stage. Significant differences appeared in eight of the 134 components of Marianne lines and in 20 of the 250 components for Mirasol lines. Such differences, even restricted to a few components, might account for honeybees' discrimination between genotypes or flowering stage. Experiments then were conducted in a flight room using an artificial flower device. A total volatile extract was used as a conditioning scent previous to the test where the total extract was successively compared to several of its subfractions. Fractions significantly less visited than the total extract were discarded, whereas fractions confused with the total extract were kept. From step to step, a restricted fraction of 28 polar components, among which 15 were identified, was shown to be as active as the initial conditioning extract. These data emphasized honeybees' abilities to generalize from simplified to more complex chemical information. Finally, this work considers the possible use of such plant chemicals, from nectars or aromas, either as targets for genetic modification of crop plants or as direct attractants when sprayed on the crop, for the improvement of entomophilous cross pollination. 相似文献
34.
Robert Chiron 《Journal of chemical ecology》1982,8(4):709-713
A new synthesis of (E)-10-hydroxy-2-decenoic acid (royal jelly acid) is described, starting from 8-bromo-1-octanol via condensation of malonic acid with 8-hydroxyoctanal or 8-acetoxyoctanal. 相似文献
35.
本文概述了花粉的化学成分及其营养价值。根据有关资料充分说明了中国及世界花粉蕴藏量极为丰富,进一步综述了花粉资源开发利用的现状及前景并指出花粉是人类蛋白质的新资源。 相似文献
36.
One of the most critical issues in using service‐oriented technologies is the combination of services, which has become an important challenge in the present. There are some significant challenges in the service composition, most notable is the quality of service (QoS), which is more challenging due to changing circumstances in dynamic service environments. Also, trust value in the case of selection of more reliable services is another challenge in the service composition. Due to NP‐hard complexity of service composition, many metaheuristic algorithms have been used so far. Therefore, in this paper, the honeybee mating optimization algorithm as one of the powerful metaheuristic algorithms is used for achieving the desired goals. To improve the QoS, inspirations from the mating stages of the honeybee, the interactions between honeybees and queen bee mating and the selection of the new queen from the relevant optimization algorithm have been used. To address the trust challenge, a trust‐based clustering algorithm has also been used. The simulation results using C# language have shown that the proposed method in small scale problem acts better than particle swarm optimization algorithm, genetic algorithm, and discrete gbest‐guided artificial bee colony algorithm. With the clustering and reduction of the search space, the response time is improved; also, more trusted services are selected. The results of the simulation on a large‐scale problem have indicated that the proposed method is exhibited worse performance than the average results of previous works in computation time. 相似文献
37.
蜂蛹黄酮的提取及体外抗氧化作用的研究 总被引:4,自引:0,他引:4
研究了利用超声波技术对蜂蛹黄酮的辅助提取工艺及提取物的体外抗氧化作用.结果表明,超声波辅助提取蜂蛹黄酮时间短、效果好.最佳提取工艺条件为:提取溶剂为甲醇,超声波强度34W/cm2,超声波处理时间20min,料液比1:15.黄酮的一次提取量为43.85mg/100g.蜂蛹黄酮对碱性邻苯三酚自氧化产生的超氧阴离子、Fenton反应产生的羟基自由基和Fe2 诱发卵黄低密度脂蛋白(LDL)多不饱和脂肪酸(PUFA)过氧化产生的烷氧基(LO·)和烷过氧基(LOO·)均有明显的抑制作用,且均呈现一定的量效关系. 相似文献
38.
39.
Cooke Maile H. Y.; Couvillon P. A.; Bitterman M. E. 《Canadian Metallurgical Quarterly》2007,121(1):106
In a recent experiment on short-term memory (P. A. Couvillon, T. P. Ferreira, & M. E. Bitterman, 2003), honeybees (Apis mellifera) learned to choose between 2 colors on the basis of immediately preceding experience with 1 of them. Some learned to choose the same color as the sample (perseveration or matching), others to choose the alternative color (alternation or nonmatching). Performance in the 2 problems was very much the same. In the present experiment, honeybees learned no less readily to choose between the 2 colors on the basis of sample stimuli that were different from the colors (symbolic matching). A simple associative interpretation of the results is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
The response of honey bee (Apis mellifera L.) drones to queen pheromone(s) (either natural from a mated queen, or synthetic from a lure) was recorded using an X-band, ground-based radar. The distribution of drones (insect targets on the radar screen) changed from a scattered distribution to a line concentration (downwind) when the pheromone was released. Displacement within the line concentration was toward the pheromone. This response was seen as far as 800±15 m downwind from a lure with 10 mg of synthetic 9-oxodec-trans-2-enoic acid (9-ODA) and as far as 420±15 m from a mated queen. These studies demonstrate that queen pheromone can be detected by drones at much greater distances than previously believed and illustrate how X-band radar may be used to establish the distances at which insects of similar or larger size respond to pheromones.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA. 相似文献