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51.
The characteristics and functional properties of gelatin from skin cuttlefish (Sepia officinalis) were investigated and compared to those of halal bovine gelatin (HBG). The gelatin extraction efficiency was improved by an acid-swelling process in the presence of smooth hound crude acid protease extract (SHCAP). The yields of gelatins from cuttlefish skin after 48 h with acid and with crude acid protease (15 units/g alkaline-treated skin) were 2.21% and 7.84%, respectively. The gelatin from skin cuttlefish had high protein (91.35%) but low fat (0.28%) contents. Compared to HBG, the cuttlefish-skin gelatin (CSG) has different amino acids composition than halal bovine gelatin. CSG contained slightly low hydroxyproline and proline (180‰) than HBG (219‰), whereas the content of serine was higher (49‰ versus 29‰). The gel strength of the gelatin gel from CSG (181 g) was lower than that of HBG (259 g) (p < 0.05) possibly due to lower hydroxyproline content. Cuttlefish-skin gelatin exhibited a similar emulsifying activity but greater emulsifying and foam stability than the halal bovine gelatin (p < 0.05). Foam formation ability, foam stability and water-holding capacity of CSG were slightly lower than those of the HBG, but fat-binding capacity was higher in the cuttlefish gelatin.  相似文献   
52.
Concentrations of cadmium (Cd), copper (Cu), mercury (Hg), and zinc (Zn) were determined by atomic absorption spectrophotometry in the muscle tissues (arms and mantle) of 3 commercial cephalopods (Loligo vulgaris, Octopus vulgaris, and Sepia officinalis) caught in 3 different Tunisian coastal regions. The highest concentrations found correspond to the essential elements Cu and Zn. Octopuses and cuttlefish showed the highest levels of those elements whereas squid presented with significantly higher values of Hg in both muscular tissues. This may be related to different feeding behavior and detoxification processes among benthic and pelagic cephalopods. Variation of element concentrations between seasons was different between species and seemed to be mostly dependent on the sampling site. From a public health standpoint, average concentrations of Cd, Cu, Hg, and Zn measured in edible tissues of cephalopods from this study did not reveal, in general, any risk for consumers. The estimated target hazard quotients for Cd and Hg for consumers of the selected species were below 1 and within the safety range for human health. Moreover, their consumption could provide in an important contribution to the daily dietary intake of Cu for the Tunisian population, especially regarding the consumption of octopus and cuttlefish muscles.  相似文献   
53.
54.
After more than four decades of assisted reproductive technology (ART) practice worldwide, today more than 60% of women undergoing in vitro fertilization (IVF) treatments fail to become pregnant after the first embryo transfer and nearly 20% of patients are suffering from unexplained recurrent implantation failures (RIFs) and repeated pregnancy loss (RPL). The literature reported different causes of RIF–RPL, mainly multifactorial, endometrial and idiopathic. RIF remains a black box because of the complicated categorization and causes of this physio-pathological dysregulation of implantation and pregnancy process after ovarian stimulation. Many options were suggested as solutions to treat RIF–RPL with controversial results on their usefulness. In this article, we reviewed different possible therapeutic options to improve implantation rates and clinical outcomes. Based on our experience we believe that endometrium immunomodulation after intrauterine insemination of activated autologous peripheral blood mononuclear cells (PBMCs) or platelet-rich plasma (PRP) can be a promising therapeutic solution. On the other hand, peripheral lymphocyte balance typing, specific cytokines and interleukins profiling can be proposed as predictive biomarkers of implantation before embryo transfer.  相似文献   
55.
3D urban maps with semantic labels and metric information are not only essential for the next generation robots such autonomous vehicles and city drones, but also help to visualize and augment local environment in mobile user applications. The machine vision challenge is to generate accurate urban maps from existing data with minimal manual annotation. In this work, we propose a novel methodology that takes GPS registered LiDAR (Light Detection And Ranging) point clouds and street view images as inputs and creates semantic labels for the 3D points clouds using a hybrid of rule-based parsing and learning-based labelling that combine point cloud and photometric features. The rule-based parsing boosts segmentation of simple and large structures such as street surfaces and building facades that span almost 75% of the point cloud data. For more complex structures, such as cars, trees and pedestrians, we adopt boosted decision trees that exploit both structure (LiDAR) and photometric (street view) features. We provide qualitative examples of our methodology in 3D visualization where we construct parametric graphical models from labelled data and in 2D image segmentation where 3D labels are back projected to the street view images. In quantitative evaluation we report classification accuracy and computing times and compare results to competing methods with three popular databases: NAVTEQ True, Paris-Rue-Madame and TLS (terrestrial laser scanned) Velodyne.  相似文献   
56.
This paper presents one of the first attempts to measure and model the ellipsometric data for ternary nitride coatings in general and TiBN coatings in particular. TiBN coatings with a functionally graded underlayer of Ti/TiN have been deposited at low temperatures (<200 °C) on a silicon substrate using ion beam assisted deposition (IBAD). The coating selected for detailed analysis had a total thickness of 1.5±0.2 μm. The deposited structure was characterized post-deposition using X-ray diffraction (XRD), atomic force microscopy (AFM), Rutherford backscattering (RBS), X-ray photoelectron spectroscopy (XPS), infrared spectroscopic ellipsometry (IR-SE), and visible-light spectroscopic ellipsometry (VIS-SE). The primary phases (TiB2, TiN, and BN) in the film were identified using XRD. The surface morphology and nanocrystalline nature of the coating (grain size of 5–7 nm) were deduced using AFM. The chemical composition and phase composition of the sample was determined from RBS and XPS measurements and was subsequently deduced from the analysis of the VIS-SE data. The refractive indices for the constituent phases were deduced from the investigation of TiB2, TiN and BN single layers with SE. Good correlation was observed between RBS, XPS and VIS-SE for the data on the TiBN sample. XPS and IR-SE suggested that BN formed in the amorphous form. The chemical composition study using these various techniques shows that in-situ SE is a potential technique to control the growth of ternary nitride coatings. Finally, the mechanical properties of the coating were evaluated using a nanoindenter. The hardness and elastic modulus were measured to be 42 GPa and 325 GPa, respectively.  相似文献   
57.
The brightest students entering postsecondary education are often attracted by routes other than engineering that are perceived more likely to yield careers of higher prestige and greater returns. For civil engineering in particular, this is further compounded by the fact that the field is not traditionally viewed as a high-tech discipline. Thus, student quality, enrollment, and research funding in civil engineering programs have been declining across North America. The conservative construction industry is part of the problem; adjustments of this aging cartel to the new economy are still at the embryonic level. Civil engineering educators are facing the question, How do we change the “hard hat down in the ditch” image of civil engineering in the minds of the new information technology generation? This paper presents an analysis of possible causes of this problem and a vision for potential future solutions.  相似文献   
58.
The eigenvalue approach is developed for the two-dimensional problem in a micropolar thermoelastic medium for a half-space subjected to distributed loading and zero temperature change. The formulation is applied to the coupled theory as well as to two generalizations, the Lord–Shulman and the Green–Lindsay theories. The Fourier transforms are inverted analytically. The inversion of the Laplace transforms are carried out using the inversion formula of the transform together with Fourier expansion techniques. Numerical methods are used to accelerate the convergence of the resulting series and to evaluate the improper integrals involved to obtain temperature, displacement, force and couple stress in the physical domain. The results of micropolar elasticity and generalized thermoelasticity are deduced as special cases from the present formulation. Numerical results are represented graphically and discussed.  相似文献   
59.

Interactions caused by thermal and mechanical sources in a generalized thermo-microstretch elastic medium are studied by the use of Laplace-Fourier transform techniques. The formulation is applied to the coupled theory as well as to two generalizations, the Lord-Shulman and the Green-Lindsay theories. The integral transforms are inverted using a numerical technique to obtain the solutions field in the physical domain. Stretch effects lead to the existence of a new wave that is called longitudinal microstretch wave. The results of micropolar generalized thermoelasticity and generalized thermoelasticity are deduced as special cases from the present formulation.  相似文献   
60.
In the present study, betalains content, phenolic composition, and antioxidant activity of different parts of red beet (Beta vulgaris L. conditiva) (i.e., roots and stems) were compared. Crude extract of root showed the highest betalain content with a maximum of 53 ± 4 mg betanin eq and 46 ± 3 mg vulgaxantin I eq g?1 of extract stems showed higher total phenolic concentration than roots, ranging between 2.0 ± 0.4 and 14.6 ± 0.5 mg gallic acid eq?1 of extract. Chemical composition was analyzed using LC-MS. Betalains (vulgaxanthin I, betanin, and isobetanin) and phenolics (gallic acid, ferulic acid, chlorogenic acid, caffeic acid, vanillic acid, syringic acid, ellagic acid myricetin, quercetin, rutin, kampferol) were identified in roots and stems. Betalain extract obtained from roots showed higher antioxidant activity than extract obtained from stems.  相似文献   
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