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61.
Healthy adults (N?=?28) participated in a randomized trial of Bonny Method of Guided Imagery and Music (GIM; a depth approach to music psychotherapy) sessions on mood and cortisol. Participants in both GIM and wait-list control conditions completed the Profile of Mood States (POMS) and donated 15 cc of blood before and after the 13-week intervention period and again at a 6-week follow-up. Split-plot factorial and post hoc analyses demonstrated that after 6 biweekly sessions GIM participants reported significant decreases between pre- and postsession depression, fatigue, and total mood disturbance and had significant decreases in cortisol level by follow-up. Pretest to follow-up decrease in cortisol was significantly associated with decrease in mood disturbance. A short series of GIM sessions may positively affect mood and reduce cortisol levels in healthy adults. Such changes in hormonal regulation may have health implications for chronically stressed people. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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63.

Purpose

to evaluate the role of whole brain radiotherapy (WBRT) and radiation boost (RB) for 208 patients recursive partitioning analysis (RPA) II with 1 or 2 brain metastases (BM) at a single institution.

Methods and Materials

the dose of WBRT was 30 Gy (10 fractions of 3 Gy). One hundred thirty-two patients (63.5%) benefited from RB of 9 Gy in 3 fractions of 3 Gy at the metastatic site. Patients had 1 or 2 BM in 122 (58.7%) and 86 cases (41.3%), respectively.

Results

patients with one or two metastases had similar survival (4.6 and 5.1 months, respectively) (p = 0.4). Median overall survival (OS) for patients treated with WBRT and RB, and with WBRT alone was 5.9 and 3.7 months, respectively (p = 0.03). The 6-, 12- and 24-month OS rates after WBRT and RB were 48.5%, 25% and 10.6%, respectively, while WBRT alone resulted in OS rates of 34%, 22.4% and 3.2%, respectively (p = 0.03). After WBRT and RB, the 6-, 12- and 24-month local control rates were 92%, 82% and 67%, respectively, while they were 81.2%, 75% and 37.5%, respectively, after WBRT alone (p = 0.03). The 6-, 12- and 24-month brain control rates after WBRT and RB were 88.7%, 75.8% and 62%, respectively, and after WBRT alone they were 78.5%, 59% and 37.7%, respectively (p = 0.03).

Conclusion

additional boost delivered with 3D conformal radiotherapy improves local and brain control rates significantly as well as overall survival for RPA II patients with 1 or 2 unresectable BM.  相似文献   
64.
MaxPHOS is an active and robust P‐stereogenic ligand for asymmetric catalysis. The presence of an  NH bridge between the two phosphine moieties allows the NH/PH tautomerism to take place. The neutral ligand, in which the NH form predominates, is an air‐sensitive compound. However, protonation of MaxPHOS leads to the stable PH form of the ligand, in which the overall positive charge is distributed on both P centers. This protonation turns the MaxPHOS⋅HBF4 salt 3 into an air‐stable compound both in the solid state and in solution. The salt 3 is also a convenient precursor for the preparation of rhodium(I) complexes by direct ligand exchange with the complex [Rh(acac)(cod)]. Finally, the corresponding rhodium(I)‐MaxPHOS complex was tested in the asymmetric hydrogenation of a wide range of substrates. The complex proved to be a highly selective and robust system in these reactions.

  相似文献   

65.
The repair and regeneration of large bone defects resulting from disease or trauma remains a significant clinical challenge. Bioactive glass has appealing characteristics as a scaffold material for bone tissue engineering, but the application of glass scaffolds for the repair of load-bearing bone defects is often limited by their low mechanical strength and fracture toughness. This paper provides an overview of recent developments in the fabrication and mechanical properties of bioactive glass scaffolds. The review reveals the fact that mechanical strength is not a real limiting factor in the use of bioactive glass scaffolds for bone repair, an observation not often recognized by most researchers and clinicians. Scaffolds with compressive strengths comparable to those of trabecular and cortical bones have been produced by a variety of methods. The current limitations of bioactive glass scaffolds include their low fracture toughness (low resistance to fracture) and limited mechanical reliability, which have so far received little attention. Future research directions should include the development of strong and tough bioactive glass scaffolds, and their evaluation in unloaded and load-bearing bone defects in animal models.  相似文献   
66.
The investigation on incorporating nitrogen group into titanium dioxide in order to obtain powdered visible light-active photocatalysts is presented. The industrial hydrated amorphous titanium dioxide (TiO2·xH2O) obtained directly from sulphate technology installation was modified by heat treatment at temperatures of 100–800 °C for 4 h in an ammonia atmosphere. The photocatalysts were characterized by UV–VIS–DR and XRD techniques. The UV–VIS–DR spectra of the modified catalysts exhibited an additional maximum in the VIS region (, ) which may be due to the presence of nitrogen in TiO2 structure. On the basis of XRD analysis it can be supposed that the presence of nitrogen does not have any influence on the transformation temperature of anatase to rutile. The photocatalytic activity of the modified photocatalysts was determined on the basis of decomposition rate of phenol and azo-dye (Reactive Red 198) under visible light irradiation. The highest rate of phenol degradation was obtained for catalysts calcinated at 700 °C (6.55%), and the highest rate of dye decomposition was found for catalysts calcinated at 500 and 600 °C (ca. 40–45%). The nitrogen doping during calcination under ammonia atmosphere is a very promising way of preparation of photocatalysts which could have a practical application in water treatment system under broader solar light spectrum.  相似文献   
67.
We propose a new method that eases the definition of integrity constraints in object-oriented conceptual modeling languages. The essence of the method is to represent constraints by special operations that we call constraint operations. The formal specification of these operations is the definition of the corresponding constraints. The method allows the specialization of constraints and the definition of exceptions. The main application of the method is for static constraints. However, a variant of it can also be applied for creation-time and deletion-time constraints, two particular classes of temporal constraints. The method can be adapted to any object-oriented language, and we show its adaptation to the UML. We also show that our method has several advantages over existing methods.  相似文献   
68.
The metal–ferrite composite (Fe0.2Co0.8)0.8(Fe2.38Co0.62O4) has been studied by X-ray diffractometry measurements and high-resolution transmission electron microscopy. Spinel ferrite occurs in highly crystalline domains 100–150 nm in size, and the iron–cobalt alloy occurs in smaller and less-crystalline domains (10–20 nm). Both phases are heterogeneous in composition. The metal is embedded in the spinel phase, located near the edges, and overlaid by a poorly crystallized layer or misshapen regions containing small spinel crystals and amorphous phases. By annealing under vacuum up to 800°C, the misshapen regions disappear and the size of the metallic regions increases. The concentration of iron in the metallic regions decreases and their structure changes to face-centered cubic, while the spinel becomes enriched in iron.  相似文献   
69.
In the functional diagnostics of human sensor systems, the analysis of stimulus responses embedded in an electroencephalogram (EEG), e.g. evoked potentials (EPs), is of high relevance for an objective electrophysiological assessment. The aim of this work is to detect weak EPs from highly contaminated signal traces. In principle this can be done using methods of spatiotemporal signal processing, which simultaneously increase the weak SNR (signal-to-noise ratio). However, methods based on any a priori knowledge of spatial or temporal properties as well as the propagation speed and direction are not applicable. Models with adjustable signal properties similar to real cortical activity are necessary for the development and evaluation of new methods of spatiotemporal signal processing. A model is needed which can be used in forward- and inverse-projection calculations. This study aims to develop a signal generator of the background EEG activity with embedded EPs of fully adjustable signal parameters. The study also compares the results of modeled signal analysis by known methods for signal decomposition, SVD (singular value decomposition) and ICA (independent component analysis).  相似文献   
70.
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