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1.
Industrial-grade cardanol and 2-mercaptoethanol were reacted to generate hydroxyl-functionalized cardanol by UV, free-radical-initiated thiol-ene coupling between the double bond moieties of the cardanol long carbon side chain and thiol functional groups. The average hydroxyl number of the hydroxyl-functionalized cardanol was controlled by reaction time, with the hydroxyl values of this ranging within 168–201 mg KOH g−1. This cardanol was then used as a polyol to prepare cardanol-based polyurethane with hexamethylene diisocyanate and a NCO/OH ratio of 1. To compare the effect of cardanol-based polyols with the properties of cardanol-based polyurethane, cardanol modified with 10-undecylenate was used as a raw material to prepare cardanol-based polyols, including the long carbon chain of 10-undecylenate. All properties were examined, and data revealed that cardanol-based polyols including this long carbon chain can improve the hydrophobic and mechanic properties of the cardanol-based polyurethane. 相似文献
2.
Based on the multi-item Food Choice Questionnaire (FCQ) originally developed by Steptoe and colleagues (1995), the current study developed a single-item FCQ that provides an acceptable balance between practical needs and psychometric concerns. Studies 1 (N = 1851) and 2 (2a (N = 3290), 2b (N = 4723), 2c (N = 270)) showed that the single-item FCQ scale has good convergent and discriminant validity. Generally, the results showed the highest correlations with the related multi-item dimensions (>0.40). Study 2 refined the scale. Only the items for convenience (Study 2a), sensory appeal (Study 2b) and mood (Study 2c) needed to be revised (as Study 1 showed a correlation between the multi-item and the single-item below the threshold of 0.60). The results also showed comparable predictive validity. Both methods revealed similar association patterns between food motives and consumption behaviours (Fisher’s z tests revealed agreements of 86.2% for Study 1, 92.9% for Study 2a and 100% for Studies 2b and 2c). Study 3 (N = 6062) showed an example of the added value of a context-specific application for the single-item FCQ. Different motives were shown to be relevant across contexts, and the context-specific motives had additional explained variance beyond the general multi-item FCQ. Studies 2b and 3 also showed the performance of the single-item FCQ in an international context. In sum, the results indicate that the single-item FCQ can be used as a flexible and short substitute for the multi-item FCQ. The study also discusses the conditions that should be considered when using the single-item scale. 相似文献
3.
Radio frequency (RF) heating has been applied to process foods due to its unique advantages like volumetric heating. To investigate the interaction between dispersed liquid food and electromagnetic field, four dispersion structures, formed by polypropylene pellets dispersed in the samples, and six solutions with different ion concentrations were analyzed. The Results showed that 4 mm dispersion structure and 0.01 mol/L ion concentration involved in the highest heating rate and made the heating rate increase from 1.23 °C/min to 5.53 °C/min. For materials with different ion concentrations, the maximum heating rate corresponded to the dispersion structure of different sizes. But the dispersion structure would reduce the heating uniformity of the horizontal surface of materials. It suggested that dispersion structure and an proper ion concentration could change the material into a dispersed status, further improve RF heating rate, and ensure the efficiency of sterilization as well as retain the nutrition of foodstuffs. 相似文献
4.
The microstructures of Cu films deposited by the self-ion assisted, partially ionized beam (PIB) deposition technique under
two different accelerating potentials, 0 KeV and 6 KeV, are compared. The 6 KeV film shows a bimodal (111) fiber and (100)
fiber texture with an abundance of twin boundaries and a relatively large average grain size with a typical lognormal distribution.
The 0 KeV film consists of small, mostly (111) oriented grains with islands of abnormally large (100) grains. The controlling
factors for the abnormal growth of the (100) grains are discussed in relation to the observed microstructures, showing that
all factors necessary for abnormal (100) growth are present in the films. 相似文献
5.
Structure-property relationships in a series of thermoset organotin polymers have been investigated. The tri-n-butyltin esters of glycine, 4-aminobutanoic, 6-aminohexanoic, and 11-aminoundecanoic acids were synthesized and reacted with diepoxides to prepare prepolymers carrying epoxide end groups. The prepolymers were crosslinked by diethylenetriamine or metaphenylenediamine. Similar epoxy network polymers were prepared directly from the tributyltin ester of 3,5-diaminobenzoic acid which was also synthesized. The strength, moduli, toughness, glass transition and dynamic mechanical response of the polymers were investigated, and correlated with structural changes introduced in the network. The results establish the utility of the adopted synthesis schemes in exercising considerable control over the bulk polymer properties, and consequently, in modifying the controlled release of organotin groups from the crosslinked network. 相似文献
6.
Yield Stress and Microstructure of Set Yogurt Made from High Hydrostatic Pressure-Treated Full Fat Milk 总被引:1,自引:0,他引:1
F. Harte M. Amonte L. Luedecke B.G. Swanson G.V. Barbosa-Cánovas 《Journal of food science》2002,67(6):2245-2250
ABSTRACT: Set yogurts were prepared from fortified milk subjected to the following processes: (a) Thermal process (85C,°C,35 min), (b) High hydrostatic pressure process (193 or 676 MPa for 5 or 30 min), and (c) Nonprocessed milk (control). Yogurts from milk treated with 676 MPa for 30 min exhibited similar yield stress and water-holding capacity (WHC) to yogurts from heated milk. Transmission Electron Microscopy (TEM) micrographs exhibited small round casein micelle aggregates without appendages in yogurts from heated milk. Yogurts from milk treated with 193 MPa and untreated milk exhibited low yield stress, low WHC, and large clusters of coalesced micelles. Mechanisms for gel formation are discussed. 相似文献
7.
Chlorogenic acid at 5° published threshold concentration (100 mg/ L) in aqueous 0.2% potassium acid tartrate was not significantly more bitter than aqueous 0.2% potassium tartrate alone when evaluated by taste panel. 相似文献
8.
9.
In the gold wire bonding of aluminum in microelectronic devices the presence of aluminum oxide on the metallization surface may be expected. Electron transparent couples containing an oxide layer at the interface were heated in a TEM to determine the effects of a passivation layer on intermetallic formation. Intermetallic phases were evidenced by changes in sample appearance and their structure was determined by electron diffraction. The presence of an oxide at the interface hindered second phase formation at temperatures at which they were usually expected to form. In aluminum rich couples, the formation of the AuAl2 intermetallic was not observed to form until about 350°C with the oxide present. In a reverse configuration involving a gold rich couple, an amorphous oxide phase was observed between the Al and the advancing Au2Al front. The movement of the reaction front appeared to be controlled by surface diffusion across this phase. 相似文献
10.
Ass. Prof. H. M. Zbib 《Acta Mechanica》1991,87(3-4):179-196
Summary The macroscopic behavior of materials subjected to large deformations is investigated by considering the structure and mechanics of the single slip. Physically based constitutive relations for the plastic flow and material spin are then rigorously derived by resorting to the concept of non-coaxiality; yielding a class of vertex-type plasticity models incorporating features like noncoaxiality and large material rotation. It is shown that these phenomena are inherently coupled through the concept of plastic spin as it relates to the persistence of noncoaxiality. The implication of such phenomena to large deformations is investigated by examining their influence on the development of axial effects accompanying finite shear deformation, as well as on the onset of localized shear bands. 相似文献