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81.
A new numerical method to calculate the stress intensity factors (SIFs) of a three-dimensional interface crack between dissimilar anisotropic materials was developed. In this study, the M-integral method was employed for mode separation of the SIFs. The moving least-square method was utilized to calculate the M-integral. Using the M-integral with the moving least-square method, SIFs can be automatically calculated with only the nodal displacements from the finite element method (FEM). Here, SIFs analyses of some typical three-dimensional problems are demonstrated. Excellent agreement was achieved between the numerical results obtained by the present method and the corresponding results proposed by other researchers. In addition, the SIFs of a single-edge crack, a through crack, and a semi-circular crack between two anisotropic solids in three-dimensional structures were analyzed. 相似文献
82.
Hypomagnesemia as a predictor of mortality in hemodialysis patients and the role of proton pump inhibitors: A cross‐sectional, 1‐year,retrospective cohort study 下载免费PDF全文
Rika Ago Toshihiro Shindo Masataka Banshodani Sadanori Shintaku Misaki Moriishi Takao Masaki Hideki Kawanishi 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(4):580-588
Introduction This study aimed to evaluate the association between proton pump inhibitor (PPI) use and serum magnesium levels, and the role of hypomagnesemia and PPI use as a risk factor for mortality in hemodialysis patients. Methods An observational study, including a cross‐sectional and 1‐year retrospective cohort study. The study comprised 399 hemodialysis patients at a single center, and was conducted from January to September 2014. Multiple linear regression analysis was used to investigate the independent relationship between serum magnesium levels and baseline demographic and clinical variables, including PPI and histamine‐2 receptor antagonist use. Cox regression model was used to identify lower serum magnesium level and PPI as a predictor of 1‐year mortality. Findings Serum magnesium levels were lower with PPI use than non‐PPI use (2.39 ± 0.36 vs. 2.56 ± 0.39 mg/dL, P < 0.001). Multiple linear regression analysis showed that PPI use, low serum albumin levels, and low serum potassium and high‐sensitivity C‐reactive protein (hs‐CRP) levels were significantly associated with low serum magnesium levels. A total of 29 deaths occurred during the follow‐up period. According to Cox regression analysis stratified by hs‐CRP, only high serum hs‐CRP levels (>4.04 mg/L) in association with low serum magnesium levels was an independent risk factor for 1‐year mortality (hazard ratio: 2.92; 95% CI: 1.53–6.40, P < 0.001). Discussion Serum magnesium levels are lower in PPI use. In the inflammatory state, a low serum magnesium level is a significant predictor of mortality in hemodialysis patients. 相似文献
83.
Satoshi Fukuta Keita Ogawa Masaki Nomura Mariko Yamasaki Yasutoshi Sasaki 《Holz als Roh- und Werkstoff》2017,75(3):429-437
In this study, the potential of wood-only (metal-free) load-bearing walls was proposed and tested based on the idea of using the same type of material throughout wherever possible while improving basic properties such as strength, sound insulation, and heat insulation. Specifically, a technique was tested of combining pressure sensitive adhesive tape and wood dowels in place of nails for load-bearing structures with panel reinforcement represented by wood-frame construction. For this paper, its strength was evaluated by conducting in-plane shear tests, which revealed that the initial rigidity and maximum load of the proposed test specimens were greater than that of specimens using nails for jointing. However, the shear load factor, which is calculated based on some strength parameters and which forms the foundation of housing strength design, was slightly lower than that of the nail-jointed specimen. This was because there was a large decline in post-collapse resistance and a lower calculated absorbed energy caused by brittleness. The early detachment of panels was also revealed as a problem in the tests. 相似文献
84.
Ken’ichiro Kita Masaki Narisawa Atsushi Nakahira Hiroshi Mabuchi Masayoshi Itoh Masaki Sugimoto Masahito Yoshikawa 《Journal of Materials Science》2010,45(1):139-145
The polymer blends of PCS (polycarbosilane) and PMHS-h (polymethylohydrosiloxane with high molecular weight) were prepared
by freeze-drying process of mixed benzene solution. Melt viscosity, mass loss, and gas evolution from prepared polymer blends
were analyzed. A polymer blend of HSah15 (15 mass% PMHS-h to PCS) was melt-spun to fiber form, curing by thermal oxidation
and pyrolyzed at various temperatures up to 1773 K. The obtained fibers were investigated by tensile tests, FE-SEM (field
emission scanning electron microscope) observation, and XRD (X-ray diffraction) analysis. After pyrolysis at 1273 K, there
were no pores in the cross section of the fiber derived from pure PCS; however, there were amounts of pores in the cross sections
of the fiber derived from HSah15. After pyrolysis at 1773 K, the coarse β-SiC (silicon carbide) crystals were formed on the
outside surface of the fiber derived from pure PCS; however, no remarkable β-SiC crystal were formed on the outside surface
of the fiber derived from HSah15. 相似文献
85.
86.
Cubic Co3O4 nanocrystals (NCs) were synthesized by a one-pot hydrothermal reaction in the presence of the oxidant KClO3 and the capping reagent polyvinylpyrrolidone (PVP). The as-prepared Co3O4 NCs were uniformly cubic with sharp edges and good crystallinity and showed flat surfaces with {100} facets. The capped PVP could be removed without losing cubic shape by heating the NCs at 300 °C. 相似文献
87.
Akiko Ishikura Akitoshi Mizuno Masahito Watanabe Tadahiko Masaki Takehiko Ishikawa Shinji Kohara 《Journal of the American Ceramic Society》2007,90(3):738-741
High-energy synchrotron X-ray diffraction experiments were performed for clathrate-forming barium–germanium (Ba–Ge) alloys in the liquid state near the eutectic composition. The accurate structure information of highly reactive melts has been obtained by applying electrostatic levitation technique as a containerless method. The structure information obtained from the reverse Monte Carlo simulation suggests that the short-range ordering between the Ge atoms occurs with the addition of Ba atoms in the liquid Ba–Ge alloys. This can be associated with the formation of the cage-like structure composed of the Ge atoms in the liquid alloys near the eutectic composition. 相似文献
88.
Unexpected discoveries and S-invention of design requirements: important vehicles for a design process 总被引:5,自引:0,他引:5
Designers, during a conceptual design process, do not just synthesize solutions that satisfy initially given requirements, but also invent design issues or requirements that capture important aspects of the given problem. How do they do this? What becomes the impetus for the invention of important issues or requirements? So-called ‘unexpected discoveries', the acts of attending to visuo-spatial features in sketches which were not intended when they were drawn, are believed to contribute to it. The purpose of the present research is to verify this hypothesis. Analysing the cognitive processes of a practising architect in a design session, we found that in about a half of his entire design process there were bi-directional relations between unexpected discoveries and the invention of issues or requirements. Not only did unexpected discoveries become the driving force for the invention of issues or requirements, but also the occurrence of invention, in turn, tended to cause new unexpected discoveries. This has provided empirical evidence for two anecdotal views of designing. First, designing is a situated act; designers invent design issues or requirements in a way situated in the environment in which they design. We call inventions of this sort situated-invention (S-invention). Secondly, a design process progresses in such a way that the problem-space and the solution-space co-evolve. Further, this has brought a pedagogical implication as well as an insight about an important aspect of learning by experience in design. 相似文献
89.
Power systems have become very large, and in addition the forthcoming open electricity market will make power system operation more complex. Therefore, power system operation must become more efficient and flexible. Very fast power system simulation is a means of achieving more sophisticated power system on‐line monitoring and control, and parallel computing is a key technology for very fast power system simulation. This paper proposes an efficient and fast parallel network calculation algorithm that will contribute to the development of fast power system simulation programs. Numerical examples show that the proposed method using six processors is about 4.0 times as fast as the usual serial algorithm when applied to a large‐scale radial power system and about 3.2 times as fast when applied to a large‐scale loop power system. © 2001 Scripta Technica, Electr Eng Jpn, 135(3): 26–36, 2001 相似文献
90.
Masamichi Kajita Masaki MagariKagefumi Todo Naoki KanayamaHitoshi Ohmori 《Journal of Bioscience and Bioengineering》2010,109(4):407-410
A hypermutating B cell line DT40 is useful for screening antibodies and improving affinity of the selected antibodies in vitro. To perform affinity maturation efficiently, we generated an engineered DT40 line whose immunoglobulin mutation pattern can be transformed from gene conversion into point mutation by conditional suppression of XRCC3 expression. 相似文献