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111.
采用Kelen-Tudos方法, 测定了丙烯腈(AN)与丙烯酸(AA)共聚合反应体系中单体竞聚率,探讨了不同反应体系对单体竞聚率的影响.结果表明,在水相悬浮聚合体系中,当转化率小于20%时,两单体的竞聚率同DMSO均相溶液聚合结果相近;随转化率的增加,AN竞聚率增加,AA竞聚率减小,当转化率超过50%后,两单体竞聚率变化不明显.在H2O/DMSO混合溶剂沉淀聚合中,当水含量超过80%后,两单体竞聚率向水相悬浮聚合结果靠近.随溶剂极性增大,rAN与rAA值均减小。 相似文献
112.
Effect of Heat Processing on IgE Reactivity and Cross‐Reactivity of Tropomyosin and Other Allergens of Asia‐Pacific Mollusc Species: Identification of Novel Sydney Rock Oyster Tropomyosin Sac g 1 下载免费PDF全文
Jennifer M. Rolland Nirupama P. Varese Jodie B. Abramovitch Jessica Anania Roni Nugraha Sandip Kamath Anita Hazard Andreas L. Lopata Robyn E. O'Hehir 《Molecular nutrition & food research》2018,62(14)
1 Scope
Shellfish allergy is an increasing global health priority, frequently affecting adults. Molluscs are an important shellfish group causing food allergy but knowledge of their allergens and cross‐reactivity is limited. Optimal diagnosis of mollusc allergy enabling accurate advice on food avoidance is difficult. Allergens of four frequently ingested Asia‐Pacific molluscs are characterized: Sydney rock oyster (Saccostrea glomerata), blue mussel (Mytilus edulis), saucer scallop (Amusium balloti), and southern calamari (Sepioteuthis australis), examining cross‐reactivity between species and with blue swimmer crab tropomyosin, Por p 1.2 Methods and results
IgE ELISA showed that cooking increased IgE reactivity of mollusc extracts and basophil activation confirmed biologically relevant IgE reactivity. Immunoblotting demonstrated strong IgE reactivity of several proteins including one corresponding to heat‐stable tropomyosin in all species (37–40 kDa). IgE‐reactive Sydney rock oyster proteins were identified by mass spectrometry, and the novel major oyster tropomyosin allergen was cloned, sequenced, and designated Sac g 1 by the IUIS. Oyster extracts showed highest IgE cross‐reactivity with other molluscs, while mussel cross‐reactivity was weakest. Inhibition immunoblotting demonstrated high cross‐reactivity between tropomyosins of mollusc and crustacean species.3 Conclusion
These findings inform novel approaches for reliable diagnosis and improved management of mollusc allergy. 相似文献114.
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116.
In the copolymerization of phenylacetylene with various acetylenes catalysed by WCl6·Ph4Sn, the relative reactivity of monomer decreased with increasing steric effect of monomer, e.g. HC Cn-Bu, HC Cn-Hex > HC CPh, HC Cs-Bu > HC Ct-Bu, MeCCPh, CICCPh. While 1-chloro-2-phenylacetylene (a disubstituted acetylene) showed high reactivity in the homopolymerization by Mobased catalysts, the reactivity was remarkably depressed in the presence of phenylacetylene as comonomer. Based on these results, the relative reactivity of the acetylenic monomers in copolymerization was explained in terms of competitive coordination of monomers to the propagating end. 相似文献
117.
Oxidation reactivity studies are imperative for improving carbon re-burn technologies and valuing the heat content of unburned carbon within coal combustion ashes. Non-isothermal, thermal gravimetric analysis (TGA) was used to examine the oxidation kinetics of unburned carbon in coal combustion fly ashes having different particle size distributions; TGA results were related to combustion efficiencies as measured in a bench-scale rotary kiln. The activation energy and pre-exponential factor were determined for the chemically-controlled reaction regime; the transition temperatures between chemically-controlled and partially diffusion-controlled combustion regimes were obtained for unburned carbon particles of different sizes. After the oxidation reaction rates were evaluated, the residence time distribution (RTD) of fly ashes in the rotary kiln were experimentally measured and the mean residence times related to process parameters, including the rotating velocity and kiln inclination. By comparing these results with an advective-dispersive model, the axial dispersion coefficient of fly ashes was determined. The reaction rates obtained by thermal analyses and the RTDs were used to predict combustion efficiencies within the kiln and oxidation conditions of unburned carbon using various processing options. 相似文献
118.
119.
《Journal of Nuclear Science and Technology》2013,50(4):361-366
It is strongly demanded to control reactivity for safety and steady operation of nuclear reactor. Fissile enrichment should be, therefore, accurately managed in order to carry out it. A concept of physical accounting method for adjusting fissile enrichment is very useful to manage plutonium content and to control reactivity of nuclear reactor where plutonium is used as main fissile material. The basis of the concept is shown in this paper together with the result of the application to typical prototype fast breeder reactor (FBR). The rationality for adopting the method is also quantitatively shown in this paper. 相似文献
120.
《Journal of Nuclear Science and Technology》2013,50(1):23-26
Monochlorobenzene and its para- or meta-substituted derivatives were irradiated with -γ-rays in methanol, ethanol and n-propanol containing nitrous oxide to elucidate the reactivities of these organic solutes toward solvated electrons, and also the effect of the substituent for the aromatic nucleus on the reactivities of these solutes. The value of G (N2) is seen to decrease with increasing concentration of the organic solute. Relative rate constants of these organic solutes toward solvated electrons have been determined from the competition with nitrous oxide by observing the G(N2) in there systems. Based on the results, the rate constants of the reactions of these derivatives of monochlorobenzene with solvated electrons relative to monochlorobenzene can be related to Hammett's σ function. The ρ value has been observed to be 3.3, 2.1 and 1.8 for methanol, ethanol and n-propanol respectively. The present data, together with that by Sherman(1) for 2-propanol, indicates that the ρ value is correlated linearly to the dielectric constant of the solvent. Some discussions are presented on the results thus obtained. 相似文献