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11.
Experimental results show that exothermic reactions in the heating and melting stages of electrode coating take place when the coating contains more than 35% of the exothermic mixture. Data for the effect of the amount of exothermic mixture in the electrode coating on heating and melting of the electrodes are presented. The thermal balance of melting the electrodes with the exothermic mixture in the coating is calculated. The results show that the temperature of 1273 K at which the efficiency of the exothermic reaction is high is reached at a distance of approximately 1 mm from the electrode tip. It is confirmed that the addition of up to 53.4% of the exothermic mixture to the electrode coating increases the effective efficiency of heating the parent metal (ηm) from 0.715 to 0.815 and of the electrode (ηel) from 0.28 to 0.415. 相似文献
12.
Numerical calculation data on the characteristics of linear and nonlinear fracture mechanics are presented. These characteristics help to predict the surface development of studied cracks before their initiation on the surface of a product. In addition, they provide the specified durability and strength evaluation of important elements of equipment with consideration of the kinetics of the local fracture processes along the contours of differently oriented semielliptical surface cracks with consideration of the local dimension of the stress state and their relative depth. 相似文献
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Dr. Jessica S. Kelsey Dr. Tamas Geczy Nancy E. Lewin Dr. Noemi Kedei Colin S. Hill Julia S. Selezneva Christopher J. Valle Wonhee Woo Dr. Inna Gorshkova Dr. Peter M. Blumberg 《Chembiochem : a European journal of chemical biology》2014,15(8):1131-1144
The C1 domain, which represents the recognition motif on protein kinase C for the lipophilic second messenger diacylglycerol and its ultrapotent analogues, the phorbol esters, has emerged as a promising therapeutic target for cancer and other indications. Potential target selectivity is markedly enhanced both because binding reflects ternary complex formation between the ligand, C1 domain, and phospholipid, and because binding drives membrane insertion of the C1 domain, permitting aspects of the C1 domain surface outside the binding site, per se, to influence binding energetics. Here, focusing on charged residues identified in atypical C1 domains which contribute to their loss of ligand binding activity, we showed that increasing charge along the rim of the binding cleft of the protein kinase C δ C1 b domain raises the requirement for anionic phospholipids. Correspondingly, it shifts the selectivity of C1 domain translocation to the plasma membrane, which is more negatively charged than internal membranes. This change in localization is most pronounced in the case of more hydrophilic ligands, which provide weaker membrane stabilization than do the more hydrophobic ligands and thus contributes an element to the structure–activity relations for C1 domain ligands. Coexpressing pairs of C1‐containing constructs with differing charges each expressing a distinct fluorescent tag provided a powerful tool to demonstrate the effect of increasing charge in the C1 domain. 相似文献
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Galina N. Makarenko Stanislav P. Gordienko 《Powder Metallurgy and Metal Ceramics》2001,40(11-12):601-605
Thermodynamic methods and x-ray analysis have been applied to the chemical interactions in 0.9625 B4C + 0.05 NiO + 0.0375 C, B4C + NiO, B4C + 4 NiO + 3 C mixtures; stages occur in the processes there that correspond to various temperature ranges. It is found that NiB always contains small amounts of lower borides, whose quantity does not exceed 2 mass% when the synthesis conditions are optimal. 相似文献
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T. Ya. Kosolapova G. N. Makarenko T. I. Serebryakova É. V. Prilutskii O. T. Khorpyakov O. I. Chernysheva 《Powder Metallurgy and Metal Ceramics》1971,10(1):22-26
Conclusions A study was made of the preparation of boron carbonitride by various techniques. It is shown that the method of synthesis from simple substances, involving nitriding boron and carbon black in a nitrogen atmosphere at temperatures of 1800–2000°C, yields a product corresponding, according to chemical analysis, to the composition BNC. Standard powder metallurgy techniques appear to be unsuitable for the production of massive boron carbonitride specimens.Translated from Poroshkovaya Metallurgiya, No. 1 (97), pp. 27–33, January, 1971. 相似文献
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E. V. Vlasov A. S. Ginevskii R. K. Karavosov T. M. Makarenko 《Journal of Engineering Physics and Thermophysics》2001,74(1):8-10
Results of an experimental investigation of highfrequency acoustic excitation of turbulent jets for different intensities of the acoustic field are presented. It is shown that upon reaching a certain limiting level of excitation at high frequencies, the sign of the effect changes, i.e., at this level, highfrequency excitation leads to generation of turbulence in the jet rather than its suppression. Hence it follows that the highfrequency acoustic effect that suppresses turbulence is most efficient within an optimum range of frequencies and at an optimum level of excitation. 相似文献
19.
L. F. Makarenko F. P. Korshunov S. B. Lastovskii L. I. Murin M. Moll I. Pintilie 《Semiconductors》2014,48(11):1456-1462
It is shown experimentally that, in contrast to the stable configuration of (interstitial carbon)-(interstitial oxygen) complexes (C i O i ), the corresponding metastable configuration (C i O i *) cannot be found in n-Si based structures by the method of capacitance spectroscopy. The rates of transformation C i O i * →C i O i are practically the same for both n- and p-Si with a concentration of charge carriers of no higher than 1013 cm?3. It is established that the probabilities of the simultaneous formation of stable and metastable configurations of the complex under study in the case of the addition of an atom of interstitial carbon to an atom of interstitial oxygen is close to 50%. This is caused by the orientation dependence of the interaction potential of an atom of interstitial oxygen with an interstitial carbon atom, which diffuses to this oxygen atom. 相似文献
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