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71.
The robot and computer vision community has seen a lot of novelties developed in the past few years as a result of the appearance of cheap RGB-D sensors spearheaded by the Kinect sensor. In this paper, the feasibility of using an RGB-D camera in detecting, segmenting, reconstructing and measuring chronic wounds in 3D is explored. The wound is detected by implementing nearest-neighbor approach on color histograms generated from the image. The proposed wound segmentation procedure extracts the wound contour using visual and geometrical information of the surface. A procedure comparable to KinectFusion is used for the 3D reconstruction of the wound. In order to achieve real-time performance, the whole system is realized in CUDA. The resulting system provides an accurate colored 3D model of the segmented wound and enables the user to determine the volume, area and perimeter of the wound, thereby aiding in the selection of a suitable therapy. The developed system is experimentally evaluated using the Saymour II wound care model by VATA Inc.  相似文献   
72.
Bulk ceramic samples of BiFeO3 were light doped (up to 1%) with Nb5+ in the place of Fe3+ (B-site doping) and their multiferroic properties were investigated using XRD, SEM, polarization (PMTS) and magnetization (SQUID) techniques. It is shown that even the small percentages of doping can notably change electric and magnetic behavior. Electric conductivity differs by two orders of magnitude between samples doped with 0.2% and 1% Nb. The ferroelectric behavior strongly depended on conduction mechanism, and transition from space-charge-limited current (SCLC) conduction to trap-filled limited (TFL) conduction regime reflected on a change in hysteresis patterns, particularly for the samples with 0.2% and 0.5% Nb. Separation of ZFC-FC magnetization curves occurred for all Nb concentrations and increased with Nb doping. Weak ferromagnetic behavior and the increase of remnant magnetization with Nb concentration was observed from the hysteresis measurements. Coercive field changed drastically compared to the pure BiFeO3, namely, the sample with 1% Nb exhibited very high coercive magnetic field of ~ 10?kOe.  相似文献   
73.
A novel method was proposed for the preparation of aluminosilicate-based ceramic materials by temperature induced transformation of amorphous aluminosilicates (zeolite precursors) as an alternative to conventional methods based on the thermal treatment of kaolin, feldspar and other silicate, aluminosilicate and/or oxide mixtures, or by sol-gel method.Amorphous aluminosilicate gels that are usually used as precursors for the crystallization of zeolites after exchanging their host's cations (sodium) with ammonium cations from solution were thermally treated (at 1263 K for 3 h) and yielded a mixture of mullite and amorphous silica. Further chemical treatment of the mixture with sodium hydroxide solution yielded a pure mullite phase having particle size below 100 nm.  相似文献   
74.
The effects of seed treatments, including cooking, popping, germination and flour air classification on several components of Amaranthus caudatus and A. cruentus seeds, including oil, sugars, fibre, minerals and vitamins were studied. The lipid, crude and dietary fibre, ash, and sugar contents were 71, 43, 140, 30 and 18 g kg?1 in raw A. caudatus and 85, 39, 134, 40 and 22 g kg?1 in raw A. cruentus seeds, respectively. Sucrose was the dominant sugar in the raw and thermal treated seeds of both species, while glucose and galactose were the dominant ones in the high protein and the germinated seed flours. Phosphorus, potassium, magnesium and calcium were the dominant minerals in the raw seeds of both species. Air classification increased the content of minerals by more than 35% while thermal treatments did not affect their content and germination increased the calcium and zinc contents. The ascorbic acid contents were 0.030 and 0.023 g kg?1 sample in raw A. caudatus and A. cruentus seeds, respectively. All the treatments reduced the ascorbic acid content, with a high effect for the air classification and the germinated seeds dried at 90 °C. The levels of vitamin B complex, including niacin, niacinamide, pyridoxine and riboflavin were increased in the high protein flour fraction (protein contents of these fractions of A. caudatus and A. cruentus were 263.9 g kg?1 and 246.6 g kg?1, respectively) and decreased in the thermal treated flours. Germination mostly increased the amounts of those vitamins while drying reduced their amounts. Copyright © 2005 Society of Chemical Industry  相似文献   
75.
In this study principal component analysis and artificial neural networks were used to evaluate the potential of using binary mixtures of sodium alginate and other polysaccharide biopolymers as the carriers for microencapsulation of green tea bioactive compounds. Using binary mixtures of alginate and adjunct biopolymers increased the particle size (from 722 to 1344 µm) and textural parameters of the microbeads. Chemometric techniques revealed the combination of biopolymers and their ratio as the main factors influencing the encapsulation performance. The combination of alginate with hydroxypropyl methylcellulose and locust bean gum enabled to retain the highest (-)-epigallocatechin gallate and caffeine contents, the highest total phenols encapsulation efficiency, and their most retarded release in water, confirming these as the best delivery systems of polyphenol-type active compounds and signifying their potent food applications.  相似文献   
76.
Chemical analysis showed that sunflower halawa contained higher crude ether extract than sesame halawa, while the protein, ash and crude fiber were practically similar in both. The chemical analysis emphasized the high energy value of sunflower halawa (23.3 kJ/g). The in vitro digestibility of sunflower and sesame halawas amounted to 98.9% and 98.4%, being close to that of casein (99.6%). Oil separation in sunflower halawa was followed during storage at room temperature. Although the peroxide value of sunflower halawa oil increased with prolonged storage time, rancid taste was not detected. Sensory evaluation showed no significant difference between sunflower and sesame halawas, except that the former was dark in colour. The introduction of 50% of each of sunflower and sesame tahinas in halawa manufacture is suggested to improve the quality characteristics as a means of doubling its production and reduction of importation of sesame seeds.  相似文献   
77.
The crystal structures of two mononuclear Cu(II) NH2trz complexes [Cu(NH2trz)4(H2O)](AsF6)2 (I) and [Cu(NH2trz)4(H2O)](PF6)2 (II) as well as two coordination polymers [Cu(μ2-NH2trz)2Cl]Cl·H2O (III) and [Cu(μ2-NH2trz)2Cl] (SiF6)0.5·1.5H2O (IV) are presented. Cationic 1D chains with bridging bis-monodentate μ2-coordinated NH2trz and bridging μ2-coordinated chloride ligands are present in III and IV. In these coordination polymers, the Cu(II) ions are strongly antiferromagnetically coupled with J = −128.4 cm−1 for III and J = −143 cm−1 for IV (H = −JSiSi+1), due to the nature of the bridges between spin centers. Inter-chain interactions present in the crystal structures were taken into consideration, as well as g factors, which were determined experimentally, for the quantitative modeling of their magnetic properties.  相似文献   
78.
Abstract

The globalization of markets, mergers of international companies, and integration of managerial and business processes in global corporations are changing project management fundamentals. A clearly recognizable trend in multinational companies since the mid-1980s has been globalization of R&D and competence portfolios.

Applied development is usually conducted in the form of a distributed project organization. A project team is formed across geographical, organizational, and cultural boundaries, engaging in a project with a global focus. Although a multinational project organization has great potential in many dimensions, there is no doubt that the execution of a distributed high technological project is still a great challenge.

This article identifies success factors in the management of distributed projects with global goals. The authors have focused on the practical experiences of the execution of complex multinational projects in the area of applied system development for power industry.  相似文献   
79.
The effect of liquid hot isostatic pressing (LHIP) on the structure and mechanical properties of an A356.02 alloy was examined. It was shown that LHIP provides a porosity decrease from ~0.9 to 0.2 pct due to the elimination of shrinkage voids. As a result, the yield stress (YS) increases from 200 to ~230 MPa, the ultimate tensile strength (UTS) increases from ~275 to 310 MPa, the total elongation increases from ~4 to ~7.5 pct, and the fatigue strength increases from ~88 to ~140 MPa. It was found that the sequence of LHIP and homogenization annealing highly affects the hardness and variability in fatigue strength. LHIP followed by homogenization annealing provides the lowest scattering of fatigue strength and, therefore, the fabrication of the most reliable casting components.  相似文献   
80.
The objective was to evaluate the influences of the high hydrostatic pressure extraction parameters on the recovery of anthocyanins from the grape skin pomace extracts (Vitis vinifera cv. Teran) under moderate temperatures. Studied parameters were: solvents (methanol and ethanol); solvent concentrations (30, 50, and 70%); pressures (300, 400, and 500 MPa); times (3, 6.5, 10 min); and temperatures (22, 26, 30 °C). Predominant anthocyanins in all extracts were malvidins (malvidin‐3‐glucoside as the main compound) representing 55.77% of overall anthocyanin content. The type of solvent did not significantly influence anthocyanin extraction yield, while decreased solvent concentration (increased solvent‐to‐water ratio) significantly improved extraction of anthocyanins. Increase of pressure enhanced extraction yield of the anthocyanins but temperature showed stronger impact on the anthocyanins recovery. This investigation evidenced that the best conditions for HHPE of anthocyanins from grape pomace were extraction time 3.39 min, extraction temperature 29.48 °C, pressure 268.44 MPa and solvent concentration 70%.

Practical applications

Due to increased interest for the use of cheap winery byproducts as a source of expensive polyphenols for functional food production, skins from grape pomace became valuable raw material. Therefore, there is a need to evaluate the influence of HHPE innovative extraction technology on its nutritive value during processing. Optimizing parameters for polyphenolic recovery from grape pomace is directly related with nutritional value and economics of food engineering during industrial processing. Obtained results showed that the HHPE under lower temperatures is suitable for the extraction process of anthocyanins from grape skin pomace, but more research is needed to identify other food‐grade solvents with their corresponding concentrations that are useful for the extraction assisted with high hydrostatic pressure.  相似文献   
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