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51.
52.
The goal of this study is to evaluate for the first time the composition of triacylglycerols (TAG) using ESI-TOF-MS and phospholipids species using HPLC–ESI-TOF-MS of two Capparis spinosa seed oil populations. Results show that LOO, LOP, LLO, OOO, PLL and POO were the major molecular species of triacylglycerol detected in caper seeds; where L represents linoleic acid; O, oleic acid; and P, palmitic acid. The TAG composition was significantly different among the two C. spinosa populations. In Ghar el Melh population, LOO (15.7%) was detected as the dominant TAG molecular species, followed by LOP (13.2%), LLO (12.0%) and OOO (11.4%); while, the dominant fraction was LLO (14.2%) followed by LOO (14.1%), LOP (11.5%) and PLL (10.5%) in Chouigui samples. The major component in the phospholipids fraction was phosphatidylinositol (ca. 54–91%), followed by phosphatidylglycerol, phosphatidylethanolamine and phosphatidic acid. A variety of molecular species within each class were identified. The major component in all phospholipids species contains a C-18:1 lipid chain. C16:0/C18:2-PI (ca. 28–31%) was the most abundant PI. PG species were mainly C18:2/C18:1-PG (25–32%). The major PE was C18:1/C18:1-PE (44–75%). The major PA species was C18:1/C18:1-PA (22–24%).  相似文献   
53.
The topic of modelling financial market price movements is in the heart of a wide ranging debate between fundamentalists and behaviourists. Therefore, the difficulty of the prediction is due to several features: the complexity, the non-linearity and the dynamism of the financial market system, as well as the behaviour of two categories of traders. While the irrational traders are known by a shift in their sentiments, the rational ones have a limited capacity of arbitration. While taking into account the fuzzy complementarity between the fundamentalists and the behaviourists in the explanation of financial market dynamics, this study investigates the development of a new modelling technique using fuzzy sets optimized through differential evolution. This new technique provides some applicable results in the explanation of the dynamical emergent and international financial markets.  相似文献   
54.
Abstract: Currently, pavement instrumentation for condition monitoring is done on a localized and short‐term basis. Existing technology does not allow for continuous long‐term monitoring and network level deployment. Long‐term monitoring of mechanical loading for pavement structures could reduce maintenance costs, improve longevity, and enhance safety. In this article, on‐going research to develop and validate a smart pavement monitoring system is described. The system mainly consists of a novel self‐powered wireless sensor based on the integration of piezoelectric transduction with floating‐gate injection capable of detecting, storing, and transmitting strain history for long‐term monitoring and a novel passive temperature gauge. A technique for estimating full‐field strain distributions using measured data from a limited number of implemented sensors is also described. The ultimate purpose is to incorporate the traffic wander effect in the fatigue prediction algorithms. Preliminary results are shown and limitations are discussed.  相似文献   
55.
The properties of short glass fiber reinforced thermoplastic based on polyamide 6 in humid environment are studied. Conditioning was conducted at 90°C. The combined action of water and heat (90°C) affects progressively the mechanical properties. When the injection molded samples were subjected to moisture, decrease in tensile strength and elastic modulus was observed whatever in distilled water or in salt solution. However, there is an enhancement of elongation at break with increasing exposure to humidity. After immersion in water, the fatigue life time is drastically reduced. Scanning electron microscope (SEM) was used in order to examine the fractured samples feature. Results show that water diffuses into the polymer leading to a reduction of the interfacial stress transmissibility. The major contributor of the stiffness loss is the adhesion loss between the fibers and the polymer. POLYM. COMPOS., 35:501–508, 2014. © 2013 Society of Plastics Engineers  相似文献   
56.
Delaying flavour staling, to prolong the shelf life of beer, is one of the greatest challenges facing the brewing industry today. In this study, a series of lager beers were brewed using five European barley varieties and four chemical indicators of the degree of beer ageing were correlated with the sensory evaluation: E-2-nonenal, β-damascenone, 2-furaldehyde and 5-hydroxymethyl-2-furaldehyde (5-HMF). A statistical strategy using principal component analysis and multiple linear regression was applied to draw relationships between the sensory and chemical data sets. Additionally, the relative significance of each of the chemical data on the organoleptic stability of beer was evaluated within the method. 5-HMF was the only studied carbonyl compound whose concentration cannot be used for predicting the total taste score of beers. E-2-nonenal, in contrast, was found to be the most discriminant carbonyl compound under consideration for predicting the flavour stability of beer.  相似文献   
57.
Generation of organoids from urinary tract tumor samples was pioneered a few years ago. We generated organoids from two upper tract urothelial carcinomas and from one bladder cancer sample, and confirmed the expression of cytokeratins as urothelial antigens, vimentin as a mesenchymal marker, and fibroblast growth factor receptor 3 by immunohistochemistry. We investigated the dose response curves of two novel components, venetoclax versus S63845, in comparison to the clinical standard cisplatin in organoids in comparison to the corresponding two-dimensional cultures. Normal urothelial cells and tumor lines RT4 and HT1197 served as controls. We report that upper tract urothelial carcinoma cells and bladder cancer cells in two-dimensional cultures yielded clearly different sensitivities towards venetoclax, S63845, and cisplatin. Two-dimensional cultures were more sensitive at low drug concentrations, while organoids yielded higher drug efficacies at higher doses. In some two-dimensional cell viability experiments, colorimetric assays yielded different IC50 toxicity levels when compared to chemiluminescence assays. Organoids exhibited distinct sensitivities towards cisplatin and to a somewhat lesser extent towards venetoclax or S63845, respectively, and significantly different sensitivities towards the three drugs investigated when compared to the corresponding two-dimensional cultures. We conclude that organoids maintained inter-individual sensitivities towards venetoclax, S63845, and cisplatin. The preclinical models and test systems employed may bias the results of cytotoxicity studies.  相似文献   
58.
This article presents selected problems used to assess the validity and usefulness of a first-order skew, positive coefficient, upwind scheme (SPCUS) applied to radiative transfer. This particular procedure could be incorporated in several discretization methods such as finite-volume, finite-element, or control-volume finite-element methods for the prediction of radiative transfer in participating media. The suggested scheme has been validated by application to several basic two-dimensional test problems, acknowledged by the radiative heat transfer community, and its performance has proven to be good.  相似文献   
59.
Effective performance of many image processing and image analysis algorithms is strongly dependent on accurate estimation of noise level. We exploit the simplicity and similarity of statistics of human anatomy among different subjects to develop new noise level estimation algorithm for magnetic resonance images of brain. Objects of the experiment are noise‐free 3D brain MRI of 422 subjects. There are 21 slices for each subject. For each slice, total clique potential (TCP) of Markov random field, computed from local clique potential, is indexed by 200 different levels of noise. The sample space is the set of TCP‐noise level data of each slice. The random variable is the set of indices of noise level of TCP in each element of sample space that is closest in numerical value to TCP measured from a test MRI slice. Noise level is estimated from the mean and variance of the random variable. We also report the formulation of a generalized mathematical model describing relationship between TCP and Rician noise level in brain MRI images. Our proposal can operate in the absence of signals in the background and significantly reduce modeling errors inherent in strong parametric assumptions adopted by some of the current algorithms. © 2013 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 23, 304–413, 2013  相似文献   
60.
This research focuses on the design of a high-performance MEMS LC-tank using a high Q MEMS inductor and capacitor. A two different gap varactor has been used to avoid pull-in voltage at 2.4 GHz. The layout has been done by CoventorWare software. The DC voltage is 2.5 v, which is applied to the plates and results of 2.04 pF could be gained. The Q factor of the varactor is computed at about 557.27, which is good enough to make a low-phase noise VCO. A hollow spiral inductor with a silicon base substrate for compatibility with CMOS technology has been designed. The Greenhouse equation has been used to obtain the dimensions of the inductor. A suspended inductor has been implemented to avoid substrate coupling. The simulation has been done by CoventorWare. The Q factor of the inductor has been calculated using Yue's model. The resultant values of inductance and the Q factor at 2.4 GHz, are 2.89 nH and 27, respectively, which are in good agreement with the results of theoretical computation. The results were verified with the well-documented literature.  相似文献   
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