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21.
In light of their environmental and economic interests, food byproducts have been increasingly exploited and valorized for their richness in dietary fibers and antioxidants. Phenolic compounds are antioxidant bioactive molecules highly present in grape byproducts. Herein, the accelerated solvent extraction (ASE) of phenolic compounds from wet and dried grape pomace, at 45 °C, was conducted and the highest phenolic compounds yield (PCY) for wet (16.2 g GAE/100 g DM) and dry (7.28 g GAE/100 g DM) grape pomace extracts were obtained with 70% ethanol/water solvent at 140 °C. The PCY obtained from wet pomace was up to two times better compared to the dry byproduct and up to 15 times better compared to the same food matrices treated with conventional methods. With regard to Resveratrol, the corresponding dry pomace extract had a better free radical scavenging activity (49.12%) than the wet extract (39.8%). The drying pretreatment process seems to ameliorate the antiradical activity, especially when the extraction by ASE is performed at temperatures above 100 °C. HPLC-DAD analysis showed that the diversity of the flavonoid and the non-flavonoid compounds found in the extracts was seriously affected by the extraction temperature and the pretreatment of the raw material. This diversity seems to play a key role in the scavenging activity demonstrated by the extracts. Our results emphasize on ASE usage as a promising method for the preparation of highly concentrated and bioactive phenolic extracts that could be used in several industrial applications.  相似文献   
22.
Entity resolution is an important task in data cleaning to detect records that belong to the same entity. It has a critical impact on digital libraries where different entities share the same name without any identifier key. Conventional methods adopt similarity measures and clustering techniques to reveal the records of a specific entity. Due to the lack of performance, recent methods build rules on records’ attributes with distinct values for entities to overcome some drawbacks. However, they use inadequate attributes and ignore common and empty attributes values which affect the quality of entity resolution. In this paper, we define a multi-attributes weighted rule system (MAWR) that investigates all values of records’ attributes in order to represent the difficult record-entity mapping. Then, we propose a rule generation algorithm based on this system. We also propose an entity resolution algorithm (MAWR-ER) depending on the generated rules to identify entities. We verify our method on real data, and the experimental results prove the effectiveness and efficiency of our proposed method.  相似文献   
23.
The use of dynamic dependence analysis spans several areas of software research including software testing, debugging, fault localization, and security. Many of the techniques devised in these areas require the execution of large test suites in order to generate profiles that capture the dependences that occurred between given types of program elements. When the aim is to capture direct and indirect dependences between finely granular elements, such as statements and variables, this process becomes highly costly due to: (1) the large number of elements, and (2) the transitive nature of the indirect dependence relationship.The focus of this paper is on computing dynamic dependences between variables, i.e., dynamic information flow analysis or DIFA. First, because the problem of tracking dependences between statements, i.e., dynamic slicing, has already been addressed by numerous researchers. Second, because DIFA is a more difficult problem given that the number of variables in a program is unbounded. We present an algorithm that, in the context of test suite execution, leverages the already computed dependences to efficiently compute subsequent dependences within the same or later test runs. To evaluate our proposed algorithm, we conducted an empirical comparative study that contrasted it, with respect to efficiency, to three other algorithms: (1) a naïve basic algorithm, (2) a memoization based algorithm that does not leverage computed dependences from previous test runs, and (3) an algorithm that uses reduced ordered binary decision diagrams (roBDDs) to maintain and manage dependences. The results indicated that our new DIFA algorithm performed considerably better in terms of both runtime and memory consumption.  相似文献   
24.
Data extraction programs are used to obtain approximations of raw data from published graphs. Quantitative syntheses of single-subject data require that researchers have access to valid and reliable data extraction programs. We analyzed the reliability and validity of a data extraction program, GraphClick. Three independent coders extracted data from 191 graphs from the Journal of Applied Behavior Analysis (JABA) and 15 graphs of hypothetical data. Results showed that GraphClick is both reliable and valid with nearly perfect correlations for all analyses. Suggestions are included for researchers and authors to improve the accuracy of data extraction techniques.  相似文献   
25.
Hanson F  Bendall I  Deckard C  Haidar H 《Applied optics》2011,50(18):3050-3056
Remote detection and characterization of laser beams propagating in maritime atmospheres is discussed. A model for off-axis scattered laser light based on Mie scattering from maritime aerosols is presented and compared with angle and time-resolved measurements from a pulsed laser source. We demonstrate that the direction of the source can be determined from the angle-resolved intensity and that the beam direction can be determined from arrival times of the scattered signals if the position of the laser source is known.  相似文献   
26.
The cogrinding technique is one of most effective methods for improving the dissolution of poorly water-soluble drugs and it is superior to other approaches from an economical as well as an environmental standpoint, as the technique does not require any toxic organic solvents. Present work explores the role of d-glucosamine HCl (GL) as a potential excipient to improve dissolution of a low melting point drug, ibuprofen (Ibu), using physical mixtures and coground formulations. The dissolution of the poorly soluble drug has been improved by changing the ratio of Ibu:GL and also grinding time. The results also showed that although GL can enhance the solubility of Ibu, it also reduces pH around the Ibu particles which led to poor dissolution performance when the concentration of GL is high. The effect of GL on the solubility of Ibu could be misleading if the pH of the final solution was not measured. Grinding reduced the particle size of GL significantly but in case of Ibu it was less effective. Solid state analysis (XRPD, DSC, and FT-IR) showed that ibuprofen is stable under grinding conditions, but the presence of high concentration of GL in samples subjected to high grinding times caused changes in FT-IR spectrum of Ibu which could be due to intermolecular hydrogen bond or esterification between the carboxylic acid group in the ibuprofen and hydroxyl group in the GL.  相似文献   
27.
28.
A reactive transport model was developed to simultaneously predict Cryptosporidium parvum oocyst inactivation and bromate formation during ozonation of natural water. A mechanistic model previously established to predict bromate formation in organic-free synthetic waters was coupled with an empirical ozone decay model and a one-dimensional axial dispersion reactor (ADR) model to represent the performance of a lab-scale flow-through ozone bubble-diffuser contactor. Dissolved ozone concentration, bromate concentration (in flow-through experiments only), hydroxyl radical exposure and C. parvum oocyst survival were measured in batch and flow-through experiments performed with filtered Ohio River water. The model successfully represented ozone concentration and C. parvum oocyst survival ratio in the flow-through reactor using parameters independently determined from batch and semi-batch experiments. Discrepancies between model prediction and experimental data for hydroxyl radical concentration and bromate formation were attributed to unaccounted for reactions, particularly those involving natural organic matter, hydrogen peroxide and carbonate radicals. Model simulations including some of these reactions resulted in closer agreement between predictions and experimental observations for bromate formation.  相似文献   
29.
OBJECTIVE: To investigate the effect of synovial fluid (SF) from patients with juvenile rheumatoid arthritis (JRA) on proliferation and induction of degradative and invasive phenotype in normal synovial fibroblasts, and to elucidate the contribution of SF cells to this activity. METHODS: SF and/or conditioned medium (CM) from SF cells were evaluated for their ability to (1) stimulate a proliferative response, (2) induce the "activated phenotype" capable of invading cartilage matrix, and (3) promote the release of key matrix metalloproteinases (MMP) in normal synovial fibroblasts. RESULTS: Proliferation of normal synovial fibroblasts exposed to SF or CM from SF cells of patients with JRA was up to 3 times greater than untreated controls. Concomitant with induction of an activated phenotype in the treated synovial fibroblasts, the activated form exhibited up to 250% invasiveness of cartilage matrix compared to untreated synovial fibroblasts (100%), in addition to releasing increased MMP activity, not normally associated with these quiescent cells. This induction was not solely due to tumor necrosis factor-alpha, transforming growth factor-beta, interleukin 1beta (IL-1beta), and IL-6, as SF and/or CM depleted of these cytokines sustained about 40% of their invasive and inducing ability. We observed that the mononuclear cell (MNC) population that infiltrated into the joint cavity secretes this "inducing activity," which can be maintained in culture up to several weeks. CONCLUSION: Our data suggest that the cellular component of SF releases soluble factor(s) that directly or indirectly contribute to (a) proliferation of synovial fibroblasts, and (b) production and release of extracellular MMP by synovial fibroblasts, thereby inducing a degradative and invasive phenotype culminating in cartilage and bone destruction.  相似文献   
30.
This paper concerns the simulation of a class of nonlinear continuous‐time systems under a set of initial conditions described by an ellipsoid. By getting inspiration from Lyapunov theory, we show that it is possible to derive a procedure allowing the computation of a bounding ellipsoidal envelope, which will enclose all the states that can be reached from the set of initial conditions. This numerical procedure is based on convex optimization, and it makes it possible to set a guaranteed hard bound on the evolution of the state of the system for all the possible initial conditions. At the end of the paper, we show an application of the method through an academic example. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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