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41.
42.
The congenital bilateral perisylvian syndrome is characterized by pseudobulbar palsy, moderate delay in mental and motor development and epilepsy. Three characteristic case stories are presented. Epileptic seizures are most frequently generalized: tonic, astatic, atypical absences and tonic-clonic seizures. Partial seizures are less frequent. Seizure control is often unsatisfactory. Neuroimaging demonstrates thickening of the cerebral cortex in the perisylvian area bilaterally; these changes together with the clinical picture establish the diagnosis. The etiology is unknown. 相似文献
43.
The purpose of this study was to compare probing depth resolution achieved by gingivectomy and periodontal flap techniques in the treatment of cyclosporine A- and nifedipine-induced gingival enlargement. Ten kidney transplant patients who were receiving cyclosporine A and nifedipine for at least 6 months participated in the study. Five patients were randomly assigned to the gingivectomy group and 5 patients to the periodontal flap group. Only anterior segments of the oral cavity (canine to canine) were surgically treated. Clinical measurements, including probing depths, plaque index, and gingival sulcus index, were taken at baseline, 6 weeks, 6 months, and 1 year. Results showed that probing depths, while similar for both groups in the first 6 weeks of the study, were significantly shallower for the periodontal flap group when compared to the gingivectomy group at 6 months (2.48 +/- 0.34 mm versus 4.87 +/- 0.79 mm, respectively) and 1 year (322 +/- 0.65 mm versus 6.40 +/- 1.02 mm, respectively). Within its limitations, this study suggests that the pocket reduction achieved by the periodontal flap may be sustained for longer periods of time than by the gingivectomy technique in the treatment of cyclosporine A- and nifedipine-induced gingival enlargement. 相似文献
44.
AS Stein MR O'Donnell A Chai GM Schmidt A Nademanee PM Parker EP Smith DS Snyder A Molina DE Stepan R Spielberger G Somlo KA Margolin N Vora J Lipsett J Lee J Niland SJ Forman 《Canadian Metallurgical Quarterly》1996,14(8):2206-2216
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT. 相似文献
45.
Hemoptysis secondary to an aortobronchial fistula is rare and uniformly fatal when left untreated. The authors describe a case of massive hemoptysis caused by an aortopulmonary fistula in an infected Dacron graft used successfully to repair a coarctation of the aorta. 相似文献
46.
R. K. Bayer T. A. Ezquerra H. G. Zachmann F. J. Baltá Calleja J. Martinez Salazar W. Meins R. E. Diekow P. Wiegel 《Journal of Materials Science》1988,23(2):475-480
In Part 1 and Part 2 of this paper the preparation of linear polyethylene (PE)-carbon black processed composites with conducting electrical properties was examined by means of elongation flow injection moulding. Mould geometry was optimized in the form of oriented double-armed bars so as to give enhanced mechanical properties combined with a high degree of electrical homogeneity. The present paper deals with composites using a high molecular weight PE matrix. It is shown that the injection-moulded composite material exhibits not only a lower percolation threshold, c, than the conventionally pressure-moulded isotropic sample, but also conductivities two to three orders of magnitude larger than the latter. The radial and axial conductivity profiles, for concentrations well above c, are discussed in the light of the molecular orientation variations across the bars as determined by birefringence. A segregation of primary filler particles, during flow-induced orientation, into axial channels has been shown to explain the enhancement of conductivity detected in the injected mouldings. In addition, for filler concentrations near 7%, -profile analysis indicates the development of a uniform conductive-stiff inner cylinder, several millimetres wide, homogeneously extending along the full length of the injected material. 相似文献
47.
The evolution of the amorphous structure of starch was characterized during the drying process by real‐time X‐ray wide‐angle scattering. The X‐ray diffractograms of injection‐molded starch show two superposed, rather broad, scattering maxima indicative of noncrystalline structures. The location of the two peaks has been associated to disordered starch single helices. A third maximum that arises upon drying the material in vacuum is associated to the scattering emerging from regions containing double helices. A model for the starch network is proposed, assuming a primary and a secondary component. The wider, temperature stable component appearing first, is correlated to the entanglement network of the melt. The narrower network component, which is created later, at lower temperature (secondary network), is explained by the formation of double helix regions that densify the wider primary network. The secondary network is increased strongly by the drying process. X‐ray experiments performed during the penetration of water, provoking a higher molecular mobility, reveal a better‐packed helical structure that becomes the precursor of a double helix crystalline formation. When temperature increases, the secondary network is dissolved and water molecules arrange themselves in better‐organized crystals as strongly bound crystal water. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1880–1886, 2006 相似文献
48.
Nitrogen transformations occurring in ten soils fertilized with urea were determined during incubation in the laboratory for four weeks. Urea was applied at one rate, but with different placement methods. Urea was applied in solution, as prills with a 1 cm grid spacing and as prills with no spacing. Unfertilized soils and soils amended with KNO3 solution were included as controls.Nitrite accumulated in the majority of soils treated with urea, and the maximum nitrite concentration measured was directly related to initial soil pH. Cumulative gaseous N losses as percentages of applied N were: NH3, 0-59.6; N2, 0-4.9; N2O, 0-9.9; KMnO4-N, 0-1.3; CH3ONO, 0-<0.1. No gaseous N evolution was detected in control treatments. Gaseous N losses were correlated with soil pH (NH3) maximum NO
2
-
concentration (N2, N2O, KMnO4-N) and organic C content (N2, N2O). Fertilizer placement effects were generally not significant and were small in comparison with differences between soils.
Resumo Foram determinadas, durante incubação em laboratório por quatro semanas, as transformações do nitrogênio ocorridas em dez solos fertilizados com uréia. A uréia foi aplicada a um só nivel, mas com diferentes métodos de aplicação: em solução e em grânulos com 1 cm de espaçamento de grade e em grânulos sem espaçamento. Solos não fertilizados e solos corrigidos com solução de KNO3 foram incluidos como controles.O nitrito acumulado na maioria dos solos tratados com uréia e a concentração máxima de nitrito medido foram diretamente relacionados ao pH inicial do solo. As perdas cumulativas de N gasoso tomadas em percentagens de N aplicado foram: NH3, 0-59.6; N2, 0-4.9; N2O; 0-9.9; KMnO4-N, 0-1.3; CH3ONO, 0-<0.1. Não foi detectada liberação de N gasoso nos tratamentos de controle. As perdas de N gasoso foram relacionadas com o pH do solo (NH3), concentração máxima de NO 2 - (N2, N2O, KMnO4-N) e teor de C orgânico (N2, N2O). Efeitos da aplicação de fertilizante não foram de um modo geral significativos e foram pequenos em comparação com as diferenças entre os solos.相似文献
49.
Gerhard Bayer Martin Hofmann Ludwig J. Gauckler 《Journal of the American Ceramic Society》1991,74(9):2205-2208
New oxide compounds with α-PbO2 structure have been synthesized by solid-state reactions. These are derived from ZrTiO4 and HfTiO4 by a different kind of ionic substitution. The thermal expansion behavior of these phases was investigated by means of a dilatometer and an X-ray heating diffractometer. These measurements revealed rather low expansion for some of the Zr(Me3+ /Me5+ )O4 , solid solutions. This behavior is attributed to their high expansion anisotropy, which leads to extended formation of microcracks. 相似文献
50.
Evaluation has been performed of compensators generated by means of a computerized three-dimensional treatment planning system that can utilize either digitized slice profiles or CT scans. Two methods of calculating compensator thickness are used: the modified Batho power law (dSAR) method for digitized profiles and the equivalent TAR (eqTAR) method for CT scans. This system not only compensates for patient surface contours but also compensates for internal inhomogeneities. In addition, any required wedging will be incorporated in the compensator generation. This system has been tested for a number of extreme cases with inhomogeneities and sloping contours. Good agreement was obtained between the measured and computer calculated dose profiles especially along the central axis of the beam. A "Profile Uniformity Index" was defined to quantify the goodness of dose compensation in three dimensions. Compensation using this system can achieve good dose uniformity within the target volume in all clinical cases and is definitely an improvement over systems based solely on tissue deficit. 相似文献