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211.
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213.
Increase in the amount of erythrocyte delta-aminolevulinic acid dehydratase in workers with moderate lead exposure 总被引:2,自引:0,他引:2
This report summarizes our current understanding of the heavy chain haplotypes found in our laboratories' rabbits. Independently derived data from several laboratories have been synthesizes into a consistent picture of the linked inheritance of allotypic markers found on the different heavy chain classes and subclasses of rabbit immunoglobulins in pedigreed rabbits, including the families of three apparent VH-CH recombinants. In one recombinant, the entire group of CH markers (C mu, C gamma, and C alpha) recombined with the set of VH. Although in the other two recombinants all CH markers may also have recombined as a group, in one of these only IgG and IgA CH genes were informative; in the other recombinant, only the IgG allotypes were informative. Some allotypic determinants found on IgM molecules ("conformational") appear only when a specific variable region allotype (VHa) is combined with a specific mu constant region allotype (C mu). New combinations of VHa and C mu allotypes were generated in two of the genetic recombinants and led to new "conformational" determinants. The gains and losses observed lend support to the hypothesis that the determinants result from conformations generated by the combination of allotype-specific VH and C mu protein sequences. Conceivably, DNA events that join VH to diversity (D)- and joining (J)-coding sequences or mRNA processing events that splice J to C mu could be involved in generating the sequences that form allotype-specific determinants. 相似文献
214.
Progress of psychotherapy and of related behaviour sciences makes evident the importance of a better understanding of human relations. But psychoanalysis finds it hard to describe interpersonal processes without transference. In order to remain within the conceptional frame of metapsychology it has to see interaction between individuals as the oral, aggressive or sexual cathexis of an object or as satisfaction or denial of the subject by the object. The structure of the "ego", which--in analogy to medical thinking--is conceived as an organ with its functions, is considered to have no interpersonal activities. The "ego" of the classic psychoanalytic theory is chiefly occupied with itself. It has to care for its egoistical interests and to guarantee its self-preservation. As an auxiliary and meanwhile popular concept the "self" has been introduced to describe object-relations. This concept is not sharply defined. Due to its metapsychological implications it produces additional theoretical difficulties. Linguistic studies show that every inventory of words implies a certain insight into reality. For this reason the metapsychological machine-like concept of psychic structures does not permit new ideas about interpersonal relations. If we leave metapsychology and base on colloquial speech we see that the experience of "I" is much more related to persons than the rather autistic concept of the "ego" shows. Further we learn that self-preservation cannot be an egoistical interest; it depends on the attachment to others. All feelings of self-esteem depend much more on interpersonal relations than on "narcissistic regulations". From these experiences three conclusions are derived: a) One of the main qualities of the ego is the relatedness to persons. b) The concept of narcissistic regulation as a successor of primary narcissism is no longer useful. Narcissistic traits develop as the secundary compensations if the individual failed to build up satisfactory interpersonal relations. c) The revision of (a) ego-psychology and (b) theory of narcissism asks for modifications of the therapeutic technique, where now the interest is especially concentrated on interpersonal problems instead on the pathology of the ego. 相似文献
215.
Agglomeration control of hydroxyapatite nano-crystals grown in phase-separated microenvironments 总被引:1,自引:0,他引:1
Kimiyasu Sato Yuji Hotta Takaaki Nagaoka Masaki Yasuoka Koji Watari 《Journal of Materials Science》2006,41(17):5424-5428
Materials synthesis processes that require high temperatures consume large quantities of energy that generate an environmental burden. We attempted to synthesize hydroxyapatite (HAp) nano-crystals without firing or melting. “Water in oil” (W/O) emulsions were employed as microreactors for HAp formation. The surfactant-bounded water mediated HAp crystal nucleation, and HAp nano-crystallites were obtained. The obtained particles were aggregates composed of plate-like nano-crystals and monodisperse tiny crystals. Utilization of the W/O emulsions resulted in tunable nucleation frequency and the reactant provision, and yielded HAp nano-crystals with characteristic agglomeration properties. 相似文献
216.
For a reliable derivation of the thermodynamic properties in the gaseous phase from thermodynamic equations of state, it has been pointed out that third virial coefficients significantly affect calculations of heat capacities. Among existing equations of state including internationally accepted equations, there is a large discrepancy, sometimes more than 5%, in calculated heat-capacity values near saturation. Two different approaches have been conducted in addressing this problem. One is for providing the third virial coefficient from intermolecular-potential models based on speed-of-sound measurements with a spherical resonator, and another is for confirming the effect of the third virial coefficient on density values near saturation by measuring the density precisely with a magnetic suspension densimeter. This report is focused on the latter case, i.e., precise measurements of density for 1,1,1-trifluoroethane, R143a, near saturation and some important evidence for the necessity of considering third virial coefficients for calculating reliable thermodynamic properties in the gaseous phase.Paper presented at the Seventh Asian Thermophysical Properties Conference, August 23–28, 2004, Hefei and Huangshan, Anhui, P. R. China. 相似文献
217.
We investigated the influence of metal vapor contamination of ceramic surfaces on flashover voltage (FOV) in vacuum. First, disk shape alumina (Al/sub 2/O/sub 3/) ceramics with surface resistivity (/spl rho/) of 10/sup 2/-10/sup 15/ /spl Omega/ were produced using deposition phenomena of metal vapor emitted from CuCr contacts. The impulse FOV for the ceramics decreased, as /spl rho/ reduced; FOV, the conditioning effect on FOV, and the scattering of FOV decreased when /spl rho/ was below 10/sup 12/ /spl Omega/. Therefore, the criterion value /spl rho/, which maintains excellent flashover performances of ceramic surface, is 10/sup 12/ /spl Omega/. Second, experimental vacuum interrupters (VIs) were produced to measure breakdown voltage before and after forty short-circuit current switchings with 20-40 kA/sub rms/ and were disassembled to measure the /spl rho/ of their inner ceramic surface. In a VI, which has inside diameters at both ends of the main shield much larger than the contact diameter, /spl rho/ was reduced to 10/sup 4/ /spl Omega/, further decreasing breakdown voltage between terminals. 相似文献
218.
Chuanyong Gui Akihiro Sato Yuefeng Gu Hiroshi Harada 《Metallurgical and Materials Transactions A》2005,36(11):2921-2927
We proposed a new method for developing Ni-base turbine disc alloy for application at temperatures above 700 °C by mixing
a Ni-base superalloy U720LI with a two-phase alloy Co-16.9 wt pct Ti in various contents. The microstructure and phase stability
of the alloys were analyzed using an optical microscope, a scanning electron microscope, energy-dispersive spectroscopy, and
an X-ray diffractometer. The yield strength was studied by compression tests at temperatures ranging from 25 °C to 1200 °C.
The results show that all the alloys had a dendritic structure. Ni3Ti (η) phase was formed in the interdendritic region in the alloys with the addition of Co-16.9 wt pct Ti, and its volume fraction
increased with the increase in the addition of Co-16.9 wt pct Ti. The results of exposure at 750 °C show that the addition
of Co-16.9 wt pct Ti to U720LI had a great effect on suppressing the formation of σ phase due to the reduced Cr content in the γ matrix. Compared to U720LI, the alloys with the addition of Co-16.9 wt pct Ti possessed higher yield strength. The solid-solution
strengthening of γ and γ′ and higher volume fraction of γ′ were assumed to cause this strength increase. 相似文献
219.
Takuro Tomita Ayahito Uetake Tsutomu Asahina Kentaro Kayanuma Akihiro Murayama Yasuo Oka 《Journal of Superconductivity and Novel Magnetism》2005,18(3):405-410
Spin injection processes in the double quantum dots of ZnSe-based diluted magnetic semiconductors are discussed. Double quantum
dots are fabricated from ZnSe-based double quantum wells by electron beam lithography and wet etching. In these samples, the
photo-excited carriers in the magnetic dots are injected into the non-magnetic dots. The circular polarization degrees of
photoluminescence from the non-magnetic dots are measured by micro-photoluminescence measurement system under the magnetic
field up to 5 T. The maximum spin polarization degrees of injected carriers determined from our experiment are 10% for double
quantum wells and 15% for double quantum dots. The spin injection efficiency was estimated both from the observed circular
polarization degree and the diffusion length of carriers. We concluded that the spin injection efficiency is increased in
the double quantum dots. 相似文献
220.
The magnetic properties of diluted magnetic semiconductors (DMSs) are calculated from first-principles by mapping the ab initio results on a classical Heisenberg model. By using the Korringa–Kohn–Rostoker coherent potential approximation method within the local density approximation, the electronic structure of (Ga,Mn)N and (Ga,Mn)As is calculated. Effective exchange coupling constants Jijs are calculated by using the formula of Liechtenstein et al. (A.~I. Liechtenstein, M. I. Katsnelson, V. P. Antropov, and V. A. Gubanov, 1987, J.~Magn. Magn. Mater. Vol. 67, p. 65). It is found that the range of the exchange interaction in (Ga,Mn)N is very short due to the exponential decay of the impurity wave function in the gap. On the other hand, in (Ga,Mn)As, the interaction is weaker but long ranged because the extended valence hole states mediate the ferromagnetic interaction. Monte Carlo simulations show that the TC values of (Ga,Mn)N are very low since percolation is difficult to achieve for small concentrations and the mean field approximation strongly overestimates TC. Even in (Ga,Mn)As the percolation effect is still important. 相似文献