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111.
Arnon Shani 《Journal of chemical ecology》1990,16(3):959-969
The airborne pheromone emitted by calling almond moth (Ephestia cautella) females kept in individual glass cages was mainly adsorbed on the cage surface (60–65%), but sufficient pheromone was transferred by the airflow to the extended capillaries to be measured. Four calling positions of almond moth females in the glass cages were defined. The position in which the female faced the upwind flow and the gland was free to release the pheromone was the more commonly adopted position (39% of calling females). No significant difference was found in the blend proportion between capillary and cage washings in each calling position or between calling positions. The pheromone blend and amount emitted from each of five individual females was measured on three consecutive nights and both fluctuated during the 11 hr of collection, starting 3 hr before the onset of scotophase and continuing for 8 hr into it. 相似文献
112.
Y. Shani U. Koren B.I. Miller M.G. Young M. Oron R. Alferness 《Photonics Technology Letters, IEEE》1991,3(3):210-212
A technique is presented for fabricating intersecting waveguides with a sharp junction vertex. This technique was demonstrated by fabricating buried rib waveguide Y branches on InP with a junction vertex width of about 1/8 mu m. These Y branches had lower loss than the regular blunt Y branches but suffered from a dissimilar splitting coefficient between the two arms. This technique may also be useful for fabricating other waveguide elements such as crossed waveguides, zero gap directional couplers, and optical switches. A comparison with theoretical calculations is also given.<> 相似文献
113.
114.
Sofia Binman Shimon Vega Sofia Belfer Arnon Shani 《Journal of the American Oil Chemists' Society》1998,75(4):521-525
Solid extractants for metal ions have been prepared by chemical bonding of jojoba wax to a polystyrene backbone, followed
by phosphonation or sulfur-chlorination of the jojoba moiety. In this study, the intermediates and final solid products of
the reactions were characterized by solid-state 13C and 31P nuclear magnetic resonance spectroscopy. The spectra showed the expected chemical shifts of the atoms involved in the chemical
reactions, as well as other parts of the reacting molecules. Thus, the carbonyl carbon of the jojoba chain appears at 175
ppm, the methyl carbons at 15 ppm, the polystyrene backbone at 40–42 ppm (aliphatic carbons) and 128, 137, 143–147 (aromatic
carbons). Carbons adjacent to N, S, and P appear at 45–55, 60, and 48 ppm, respectively. 相似文献
115.
TheMaladera matrida beetle (Coleoptera, Scarabaeidae, Melolonthinae), a relatively new species to science, was first identified in Israel in 1983. In the course of field observations it was found that adultM. matrida beetles emerged from the soil at sunset to feed and mate. During the first 20 min of flight, most of the beetles were males. The females emerged shortly afterwards, and aggregations numbering 20–30 individuals with equal proportions of males and females were eventually formed on peanut plants. Laboratory olfactometer bioassays showed that peanut leaves (food) attracted both males and females. Field-trapping experiments and olfactometer studies showed thatM. matrida beetles were highly attracted by live virgin females in the presence of food (cut-up peanut leaves). Another set of field trapping experiments indicated that airborne volatiles produced by live virgin females plus food had the same attracting ability as live virgin females plus food. The attraction exerted by the combination of live virgin females and peanut leave volatiles suggests a synergism effect. Accordingly, we propose a two-stage mechanism of chemical communication in theM. matrida beetles: first, the males cause mechanical damage to the host plant to attract both sexes; later, the females emit attractants (sex pheromone) while eating or shortly thereafter. 相似文献
116.
Shlomi Maliah Guy Shani Ronen I. Brafman 《Autonomous Agents and Multi-Agent Systems》2018,32(5):602-634
In contingent planning problems, agents have partial information about their state and use sensing actions to learn the value of some variables. When sensing and actuation are separated, plans for such problems can often be viewed as a tree of sensing actions, separated by conformant plans consisting of non-sensing actions that enable the execution of the next sensing action. We propose a heuristic, online method for contingent planning which focuses on identifying the next useful sensing action. We select the next sensing action based on a landmark heuristic, adapted from classical planning. We discuss landmarks for plan trees, providing several alternative definitions and discussing their merits. The key part of our planner is the novel landmarks-based heuristic, together with a projection method that uses classical planning to solve the intermediate conformant planning problems. The resulting heuristic contingent planner solves many more problems than state-of-the-art, translation-based online contingent planners, and in most cases, much faster, up to 3 times faster on simple problems, and 200 times faster on non-simple domains. 相似文献
117.
In field experiments, which started several years ago to investigate the means of chemical communication of the Maladera matrida beetle, we found that the ratio of males to females attracted to the bait (live females with food) was 3 : 2–5 : 4 60 : 40–55 : 45). These findings suggested that an aggregation pheromone is involved in the chemical communication, but the constant small preference for attracted males raised the question whether the active compound(s) is indeed an aggregation pheromone or whether it is a sex pheromone released by the female to attract the male. Since the traps used in our field studies were made of yellow plastic, we had to consider the possibility that the yellow color could have influenced the trapping of the flying beetles and biased the findings for the behavior and mode of attraction toward the source of the chemical communication. To clarify this point, we set out, in this study, to conduct field experiments in which we compared the standard yellow traps with black traps. We found that the bright yellow color did indeed affect the results for chemical communication: The total catch in the yellow traps was double that in black traps, and the male–female ratio in the black traps increased to 4 : 1(80 : 20). This result hints that a sex pheromone, and probably not an aggregation pheromone, as previously thought, is involved in the chemical communication of the M. maladera beetle. 相似文献
118.
Chlorosulfonated polyethylene membranes and hollow fibers were reacted with allylic amino jojoba to bind the wax chemically to the polymer. The modified membranes and hollow fibers were then tested in the ion‐exchange and pervaporation processes, respectively. The jojoba‐bound polyethylene membranes were selective in preventing transfer of divalent ions such as Ca2+ and Mg2+, while monovalent ion such as K+ and Na+ could penetrate the membranes. The flux of the monovalent ions depended on the amount of jojoba bound to the polymer, which acted as a barrier to the ions (the monovalent ions could be eluted by acid washing). The concentration of ions (in the range of 0.05–1.0 N) in the feed solution had little effect on the flux. Preliminary results of pervaporation of a dioxane/water mixture through hollow fibers made of jojoba‐bound chlorosulfonated polyethylene show separation of the dioxane from the water with a separation factor of 6. This technique can be applied to remove residual organic solvents in the purification of industrial waste water. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 763–768, 2001 相似文献
119.
Enhanced systemic absorption in vivo and percutaneous penetration in vitro was demonstrated after transdermal administration of diclofenac sodium formulated in U-type microemulsion. Diclofenac sodium was solubilized in a typical four-component system consisting of an oil, polyoxyethylene-10EO-oleyl alcohol (Brij 96V) as the surfactant, and 1-hexanol along water dilution line W46 (40 wt % surfactant and 60 wt % oil phase before water titration).Viscosity and small angle X-ray scattering measurements have evidenced bicontinuous structures within water fractions of 0.25 and 0.5 along the dilution line. Self-diffusion NMR studies showed that drug molecules accumulated in the interfacial film and, to some extent, dissolved in the oil. Relative to a commercial macro-emulsion cream (Voltaren® Emulgel®), microemulsions containing paraffin oil or isopropyl myristate increased the in vivo transdermal penetration rate of diclofenac by two order of magnitude, whereas the rat plasma levels were increased by one order of magnitude. The in vitro data obtained from excised rat skin were comparable to the in vivo results, but suffered from discrepancies from the ideal in vivo-in vitro correlation, which might be explained by optimal in vitro conditions of perfusion and hydration. It has also been found that when jojoba oil is formulated as the oil phase in the microemulsion, the penetration rate of the drug decreases significantly. Based on the three-dimensional structure of jojoba oil, the wax is presumed to prevent the drug from being freely diffused into the skin while migrating from the interfacial film into the continuous oil phase. 相似文献
120.