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61.
The process of expansion of urban centers in Brazil has been distinguished by the complete absence of planning. As a result, urban environments lead to land uses encroaching on, defacing and destroying landmarks. Attention is given to the Morro da Queimada Archaelogical Site. This represents an important cultural heritage of the 1720 movement of secession during the gold rush. Several ruins of mining equipments such as houses, wells, shafts and galleries have been gradually destroyed. The process of the site's loss of distinct character has been monitored since 1950 using aerial photographs and cartography. Collected data indicate a conservative annual land-use change rate of about 1.5%. This rate points to the complete destruction of the site in 2008. This paper proposes the creation of the Morro da Queimada Historical Park, within the limits of the remaining set of ruins. 相似文献
62.
Frederico Z. Poleto Geert Molenberghs Carlos Daniel Paulino Julio M. Singer 《TEST》2011,20(3):589-606
Models for missing data are necessarily based on untestable assumptions whose effect on the conclusions are usually assessed
via sensitivity analysis. To avoid the usual normality assumption and/or hard-to-interpret sensitivity parameters proposed
by many authors for such purposes, we consider a simple approach for estimating means, standard deviations and correlations.
We do not make distributional assumptions and adopt a pattern-mixture model parameterization which has easily interpreted
sensitivity parameters. We use the so-called estimated ignorance and uncertainty intervals to summarize the results and illustrate
the proposal with a practical example. We present results for both the univariate and the multivariate cases. 相似文献
63.
Edson Laureto Marco Aurélio Toledo da Silva Ricardo Vignoto Fernandes José Leonil Duarte Ivan Frederico Lupiano Dias Henrique de Santana Alexandre Marletta 《Synthetic Metals》2011,161(1-2):87-91
In this paper we investigate the optical properties of thin films produced through the layer-by-layer (LbL) technique with a poly (p-phenylene vinylene) (PPV) precursor and the Congo Red (CR) azodye. Some significant changes are observed when the PPV/CR film is irradiated with polarized laser. An increase of about 10 times in the PPV emission intensity was observed, with an irradiation time of 100 min. Photoinduced birefringence measurements revealed that a high birefringence was produced in the region of the film submitted to photo-irradiation, while a photobleaching phenomenon was observed in the same region. However, such phenomena were not detected in measurements performed at low temperatures. The results indicate that a degradation process of the CR molecules is occurring with photo-irradiation, and the changes observed in the photoluminescence spectra are correlated with the combined effects of degradation and energy transfer between the PPV light-emitting conjugated segments and CR azochromophores. 相似文献
64.
65.
Katia Rezzadori Frederico M. Penha Mariane C. Proner Guilherme Zin Jos C. C. Petrus Marco Di Luccio 《化学工程与技术》2019,42(12):2700-2708
Polymeric membranes subjected to the permeation of n‐hexane were characterized and the influence of pretreatment with ethanol on the properties of the membranes was studied to assess membrane performance and stability. The results suggest that the selectivity of the membrane depends not only on the pore size, but also to a great extent on the interaction between solvent and polymer. An increase in membrane roughness and contact angle was observed for all membranes after pretreatment with ethanol and n‐hexane permeation. Moreover, the surface free energy decreased after solvents exposure, indicating an increase in membrane surface hydrophobicity and polymer swelling. The studied membranes show feasibility of use for the recovery of solvents, if suitable process parameters are selected. 相似文献
66.
Frederico Coelho Ant?nio de P��dua Braga Ren�� Natowicz Roman Rouzier 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(6):1137-1144
Breast cancer is the second most frequent one, and the first one affecting the women. The standard treatment has three main
stages: a preoperative chemotherapy followed by a surgery operation, then an post-operatory chemotherapy. Because the response
to the preoperative chemotherapy is correlated to a good prognosis, and because the clinical and biological information do
not yield to efficient predictions of the response, a lot of research effort is being devoted to the design of predictors
relying on the measurement of genes’ expression levels. In the present paper, we report our works for designing genomic predictors
of the response to the preoperative chemotherapy, making use of a semi-supervised machine learning approach. The method is
based on margin geometric information of patterns of low density areas, computed on a labeled dataset and on an unlabeled
one. 相似文献
67.
Frederico de Souza C. H. S. Del Menezzi Geraldo Bortoletto Júnior 《Holz als Roh- und Werkstoff》2011,69(2):183-192
This study aimed at evaluating the mechanical, physical and biological properties of laminated veneer lumber (LVL) made from Pinus oocarpa Schiede ex Schltdl (PO) and Pinus kesiya Royle ex Gordon (PK) and at providing a nondestructive characterization thereof. Four PO and four PK LVL boards from 22 randomly selected 2-mm thickness veneers were produced according to the following characteristics: phenol-formaldehyde (190 g/m2), hot-pressing at 150°C for 45 min and 2.8 N/mm2 of specific pressure. After board production, nondestructive evaluation was conducted, and stress wave velocity (v 0) and dynamic modulus of elasticity (E Md ) were determined. The following mechanical and physical properties were then evaluated: static bending modulus of elasticity (E M ), modulus of rupture (f M ), compression strength parallel to grain (f c,0), shear strength parallel to glue-line (f v,0), shear strength perpendicular to glue-line (f v,90), thickness swelling (TS), water absorption (WA), and permanent thickness swelling (PTS) for 2, 24, and 96-hour of water immersion. Biological property was also evaluated by measuring the weight loss by Trametes versicolor (Linnaeus ex Fries) Pilát (white-rot) and Gloeophyllum trabeum (Persoon ex Fries.) Murrill (brown-rot). After hot-pressing, no bubbles, delamination nor warping were observed for both species. In general, PK boards presented higher mechanical properties: E M , E Md , f M , f c,0 whereas PO boards were dimensionally more stable, with lower values of WA, TS and PTS in the 2, 24, and 96-hour immersion periods. Board density, f v,0, f v,90 and rot weight loss were statistically equal for PO and PK LVL. The prediction of flexural properties of consolidated LVL by the nondestructive method used was not very efficient, and the fitted models presented lower predictability. 相似文献
68.
Stefan KozerskiLeszek ?atka Lech Pawlowski Frederico CernuschiFabrice Petit Christel PierlotHarry Podlesak Jean Paul Laval 《Journal of the European Ceramic Society》2011,31(12):2089-2098
ZrO2 + 8 wt.% Y2O3 powder of a mean diameter dVS = 38 μm was milled to obtain fine particles having mean size of dVS = 1 μm. The fine powder was used to formulate a suspension with water, ethanol and their mixtures. The zeta potential of obtained suspensions was measured and found out to be in the range from −22 to −2 mV depending on suspension formulation. The suspension was injected through a nozzle into plasma jet and sprayed onto stainless steel substrates. The plasma spray experimental parameters included two variables: (i) spray distance varying from 40 to 60 mm and (ii) torch linear speed varying from 300 to 500 mm/s. The microstructure of obtained coatings was characterized with scanning electron microscope (SEM) and X-ray diffraction (XRD). The coatings had porosity in the range from 10% to 17% and the main crystal phase was tetragonal zirconium oxide. The scratch test enabled to find the critical load in the range of 9-11 N. Finally, thermal diffusivity of the samples at room temperature, determined by thermographic method, was in the range from 2.95 × 10−7 to 3.79 × 10−7 m2/s what corresponds to thermal conductivities of 0.69 W/(mK) and 0.97 W/(mK) respectively. 相似文献
70.
This article examines how numerical intuition for prices develops after a major change in currency. University students in Portugal (Study 1) and Austria (Study 2) made price estimates for 40 different items from November 2001 to June 2002, surrounding the time at which these countries switched to the euro. Overall results are more in accordance with a relearning hypothesis, considering that price estimates become progressively more accurate by a process that is related to buying frequency and, hence, is faster for frequently bought items. An alternative global rescaling hypothesis received mixed support. Results also suggest that price estimations in euros have not yet reached a level of accuracy comparable with estimations in the former national currency. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献