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71.
Argentine ant trail pheromone disruption, using continuous release of the trail pheromone compound (Z)-9-hexadecanal, reduces the incidence of trails and foraging rates of field populations. However, little is known about the
concentrations of pheromone required for successful disruption. We hypothesized that higher pheromone quantities would be
necessary to disrupt larger ant populations. To test this, we laid a 30-cm long base trail of (Z)-9-hexadecanal on a glass surface at low and high rates (1 and 100 pg/cm) (Trail 1), and laid a second, shorter trail (Trail
2, 10 cm long, located 1.5 cm upwind) near the middle of Trail 1 at six rates (1, 10, 100, 1,000, 10,000, and 100,000 pg/cm).
We then recorded and digitized movements of individual ants following Trail 1, and derived a regression statistic, r
2, as an index of trail integrity, and also recorded arrival success at the other end of the trail (30 cm) near a food supply.
Disruption of trails required 100 fold more pheromone upwind, independent of base-trail concentration. This implies that in
the field, trail disruption is likely to be less successful against high ant-trail densities (greater concentration of trail
pheromone), and more successful against newly formed or weak trails, as could be expected along invasion fronts. 相似文献
72.
DW Andrews CL Silverman J Glass B Downes RJ Riley BW Corn M Werner-Wasik WJ Curran CE McCune RH Rosenwasser 《Canadian Metallurgical Quarterly》1995,64(4):165-182
Twenty-seven acoustic tumors in 26 patients were treated with multiple fractionated linear-accelerator-based stereotactic radiotherapy (SRT). All patients with intact pretreatment facial nerve function with either small or large tumor volumes have thus far experienced no treatment-related facial neuropathy, including 9 patients with a mean follow-up of 22.4 +/- 1.6 months. The incidence of evaluable trigeminal neuropathy was 13%, and in 5 of 7 patients with serviceable pretreatment hearing, audiometry was unchanged in the immediate posttreatment period. Longer follow-up will be necessary to evaluate hearing preservation after SRT. Tumor response with central necrosis was seen in all assessable patients. SRT can be performed for cerebellopontine angle tumors with accuracy and reproducibility. It achieves a biological response similar to single fraction radiosurgery and may lower the incidence of facial and trigeminal neuropathies. 相似文献
73.
74.
A novel surface attachment strategy that utilizes RNA-DNA surface ligation chemistry to create renewable RNA microarrays from single-stranded DNA (ssDNA) microarrays on gold surfaces is demonstrated. The enzyme T4 DNA ligase was used to catalyze the formation of a phosphodiester bond between 5'-phosphate-modified ssDNA attached to the surface and the 3'-hydroxyl group of unlabeled RNA molecules from solution in the presence of a complementary template DNA strand. Surface plasmon resonance imaging (SPRI) measurements were performed to characterize the ligation process as well as to verify the bioactivity of the ssRNA microarray in terms of (i) the hybridization adsorption of complementary DNA onto the RNA array to form a surface RNA-DNA heteroduplex and (ii) the hydrolysis of the RNA microarrays with either ribonuclease S or ribonuclease H (RNase H). The hydrolysis of the surface-bound RNA with RNase H required the presence of a surface heteroduplex and, upon completion, regenerated the original 5'-phosphate-terminated ssDNA array elements. These ssDNA array elements could be ligated again to create a new RNA microarray. These RNA microarrays can be used in the study of RNA-protein/RNA/aptamer bioaffinity interactions and for the enzymatically amplified SPRI detection of DNA in the presence of RNase H. 相似文献
75.
A novel surface enzymatic amplification method that utilizes RNA microarrays in conjunction with the enzyme RNase H is developed for the ultrasensitve detection and analysis of target DNA molecules. The enzyme RNase H is shown to selectively and repeatedly destroy RNA from RNA-DNA heteroduplexes on gold surfaces; when used in conjunction with the label-free technique of surface plasmon resonance imaging, multiple DNA targets can be detected at a concentration of 10 fM on a single chip. In addition, this method is utilized for the sequence-specific detection of the TSPY gene in both purified and unpurified PCR products. Finally, in a series of kinetics measurements, the initial rate of hydrolysis is shown to depend directly on the surface concentration of DNA-RNA heteroduplexes. 相似文献
76.
Microfluidic channels fabricated from poly(dimethylsiloxane) (PDMS) are employed in surface plasmon resonance imaging experiments for the detection of DNA and RNA adsorption onto chemically modified gold surfaces. The PDMS microchannels are used to (i) fabricate "1-D" single-stranded DNA (ssDNA) line arrays that are used in SPR imaging experiments of oligonucleotide hybridization adsorption and (ii) create "2-D" DNA hybridization arrays in which a second set of PDMS microchannels are placed perpendicular to a 1-D line array in order to deliver target oligonucleotide solutions. In the 1-D line array experiments, the total sample volume is 500 microL; in the 2-D DNA array experiments, this volume is reduced to 1 microL. As a demonstration of the utility of these microfluidic arrays, a 2-D DNA array is used to detect a 20-fmol sample of in vitro transcribed RNA from the uidA gene of a transgenic Arabidopsis thaliana plant. It is also shown that this array fabrication method can be used for fluorescence measurements on chemically modified gold surfaces. 相似文献
77.
Frits K. van Evert Joost Samsom Gerrit Polder Marcel Vijn Hendrik‐Jan van Dooren Arjan Lamaker Gerie W.A.M. van der Heijden Corné Kempenaar Ton van der Zalm Lambertus A.P. Lotz 《野外机器人技术杂志》2011,28(2):264-277
Broad‐leaved dock is a common and troublesome grassland weed with a wide geographic distribution. In conventional farming the weed is normally controlled by using a selective herbicide, but in organic farming manual removal is the best option to control this weed. The objective of our work was to develop a robot that can navigate a pasture, detect broad‐leaved dock, and remove any weeds found. A prototype robot was constructed that navigates by following a predefined path using centimeter‐precision global positioning system (GPS). Broad‐leaved dock is detected using a camera and image processing. Once detected, weeds are destroyed by a cutting device. Tests of aspects of the system showed that path following accuracy is adequate but could be improved through tuning of the controller or adoption of a dynamic vehicle model, that the success rate of weed detection is highest when the grass is short and when the broad‐leaved dock plants are in rosette form, and that 75% of weeds removed did not grow back. An on‐farm field test of the complete system resulted in detection of 124 weeds of 134 encountered (93%), while a weed removal action was performed eight times without a weed being present. Effective weed control is considered to be achieved when the center of the weeder is positioned within 0.1 m of the taproot of the weed—this occurred in 73% of the cases. We conclude that the robot is an effective instrument to detect and control broad‐leaved dock under the conditions encountered on a commercial farm. © 2010 Wiley Periodicals, Inc. 相似文献
78.
Boukas Ioannis Ernst Damien Théate Thibaut Bolland Adrien Huynen Alexandre Buchwald Martin Wynants Christelle Cornélusse Bertrand 《Machine Learning》2021,110(9):2335-2387
Machine Learning - The large integration of variable energy resources is expected to shift a large part of the energy exchanges closer to real-time, where more accurate forecasts are available. In... 相似文献
79.
Electrophilic substitutions on aromatics such as C6H5X often lead to mixtures of the ortho- and para-disubstituted products C6H4XY. The former can chelate a metallic center and hence be a potential catalyst inactivator, whenever the (X, Y) substituents have atoms with lone pairs. This general principle operates in the Friedel-Crafts acylation of anisole, a reaction of industrial importance. 相似文献
80.
Online Conversation and Corporate Reputation: A Two‐Wave Longitudinal Study on the Effects of Exposure to the Social Media Activities of a Highly Interactive Company
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Corné Dijkmans Peter Kerkhof Asuman Buyukcan‐Tetik Camiel J. Beukeboom 《Journal of Computer-Mediated Communication》2015,20(6):632-648
In this paper, we investigate whether and to what extent exposure to a company's social media activities over time is beneficial for corporate reputation, and whether conversational human voice mediates this relation. In a two‐wave longitudinal survey among 1969 respondents, we assessed consumers' exposure to an international airline's social media activities, perceived level of conversational human voice and perception of corporate reputation. The results show that consumers' level of exposure to company social media activities precedes perceptions of corporate reputation. Also, conversational human voice mediates the relation between consumers' level of exposure to company social media activities and perceptions of corporate reputation. We discuss the implications of the results for the presence of organizations in social media. 相似文献