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41.
It is generally accepted that carbohydrate fermentation results in beneficial effects for the host because of the generation of short chain fatty acids, whereas protein fermentation is considered detrimental for the host's health. Protein fermentation mainly occurs in the distal colon, when carbohydrates get depleted and results in the production of potentially toxic metabolites such as ammonia, amines, phenols and sulfides. However, the effectivity of these metabolites has been established mainly in in vitro studies. In addition, some important bowel diseases such as colorectal cancer (CRC) and ulcerative colitis appear most often in the distal colon, which is the primary site of protein fermentation. Finally, epidemiological studies revealed that diets rich in meat are associated with the prevalence of CRC, as is the case in Western society. Importantly, meat intake not only increases fermentation of proteins but also induces increased intake of fat, heme and heterocyclic amines, which may also play a role in the development of CRC. Despite these indications, the relationship between gut health and protein fermentation has not been thoroughly investigated. In this review, the existing evidence about the potential toxicity of protein fermentation from in vitro animal and human studies will be summarized.  相似文献   
42.
This study describes the construction and initial validation of the Asian American Family Conflicts Scale (FCS) with 3 samples of Asian American college students. The scale consists of 10 typical Asian American family conflicts that are rated for likelihood of occurrence (FCS-Likelihood) and seriousness of conflict (FCS-Seriousness). In Study 1, FCS-Likelihood and FCS-Seriousness had sound internal reliability, stability, and construct validity. In Study 2, FCS-Likelihood correlated with socioeconomic and cultural orientation variables. Ethnic, generation, and language differences, as well as the parent–child acculturation gap hypothesis, also were confirmed for FCS-Likelihood. In Study 3, FCS-Likelihood correlated with measures of family cohesion, adaptability, and parent-child communication. Although further validation is necessary, FCS-Likelihood in particular is a potentially useful research and clinical instrument for assessing the quality of Asian American parent–child relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
Air‐stable copper nanoclusters are good catalysts in the Cu(I)‐catalysed “click” cycloaddition of azides with terminal alkynes to give 1,4‐disubstituted 1,2,3‐triazoles. No additional base or reducing agent is required. The reaction kinetics using various copper catalyst types and the function of copper particles in this system are studied and discussed.  相似文献   
44.
As genomes evolve over hundreds of millions years, the chromosomes become rearranged, with segments of some chromosomes inverted, while other chromosomes reciprocally exchange chunks from their ends. These rearrangements lead to the scrambling of the elements of one genome with respect to another descended from a common ancestor. Multidisciplinary work undertakes to mathematically model these processes and to develop statistical analyses and mathematical algorithms to understand the scrambling in the chromo...  相似文献   
45.
Electrochemical conversion of biomass to value-added chemicals has gained impetus in recent years. Herein, we present a methodology for recovering biomass-derived 2-furoic acid from the dilute aqueous stream by reactive extraction. The reactive extraction was performed using a chemical extractant, trioctylamine (TOA), with diluents (octanol, chloroform, and diethyl ether). Equilibrium parameters influencing the recovery of 2-furoic acid were evaluated. Using TOA in various diluents, the 2-furoic acid was recovered with 85%–99% efficiency. A 1:1 complex of the 2-furoic acid—TOA was formed in the organic phase, and the experimental equilibrium complexation constant was compared with that obtained from the relative basicity and Langmuir models. The equilibrium parameters were used for column design to estimate the solvent to feed ratio (S/F) and the number of theoretical stages (NTS). The NTS required is 12 to attain 99% recovery of 2-furoic acid in counter-current extraction. The present study sheds light on the reactive extraction process adopted for process intensification with electrochemical conversion, paving the way for the commercialization of valuable products obtained from biomass.  相似文献   
46.
ABSTRACT

Extensive literature exists for simple and exact expressions of symbol error rate (SER) over fading channels under different modulation schemes whose boundaries meet at right angles. In cases where boundaries do not meet at right angles, integrals of special function in the expressions make the exact calculation most complex. In such cases only approximate solutions are possible. Also, it is noteworthy to mention that when detection is performed with proper use of the phase (phase-jitter-based approach), noise performance of the receiver improves significantly. This paper applies phase-jitter PDF-based approach to present exact and closed-form SER expression of MPSK scheme over Mixture Gamma (MG) distribution for an arbitrary array of signal points. The proposed expression is generic as MG distribution can be approximated in almost all fading/shadowed fading channel models. As a proof to the authenticity, SERs of MPSK scheme over Rayleigh and Nakagami-m fading channels are deduced from the proposed SER over generalised MG distribution. Further, a significant improvement in SER has been achieved with phase-jitter-based approach as compared to conventional (non-phase-jitter-based) approach. Finally, to confirm the correctness of the proposed expression, results are validated through comparison with the existing results and Monte Carlo simulation.  相似文献   
47.
Connections can have a significant impact on the performance of geosynthetic systems whether their intended function is separation or reinforcement. When reinforcement is the function, the connection must be considered as a limiting strength factor and evaluated by the same performance standards as the reinforcement material alone. If used in critical structures with design lives of more than 1 or 2 years, the geosynthetic and its connections must be evaluated for durability limitations such as creep, site damage and chemical degradation. Geogrid connections typically fall into this category.

Geogrid connections are accomplished by either overlapping or mechanical connections. Overlap connections must be designed and constructed to assure proper overlap lengths. Overlap length is governed by soil interaction behavior. Geogrid-soil interaction is measured by pull-out testing and pull-out performance is a function of geogrid dimensional stability. Overlaps can be secured by a variety of tyiing techniques but these ties are not efficient for load transfer. Geogrid Bodkin Joints are the preferred mechanical connection for assuring full load transfer between adjacent layers of some geogrids.

This paper discusses geogrid connections, the techniques used, and the factors that affect their performance.  相似文献   

48.
Examined whether memory improved in a series of 10 student-performed tasks in three conditions administered to students who expected a posttest. The results indicated that the subjects in a rhyming mnemonic condition recalled significantly more of the student-performed tasks than did subjects in paraphrase or control conditions. In addition, subjects in a paraphrase condition recalled significantly more student-performed tasks than did subjects in the control condition. In Experiment 2, we did not use the rhyming mnemonic condition. Results confirmed those of Experiment 1. In Experiment 3, we contrasted conditions in which unrelated student-performed tasks were used as the to-be-remembered events with conditions in which the student-performed tasks made up an overall procedure. Results indicated that the type of task influenced recall. Overall conclusions suggest that encoding of student-performed tasks is strategic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
In this second paper, the authors have obtained data from 60 building cases tried in the Supreme Courts of New South Wales and Victoria during 1990 and 1991 and from 60 cases heard in the Court system of the United Kingdom.  相似文献   
50.
Multi-dimensional Wireless sensor grids (WSG)s are deployed in complex environments to sense and collect data relating to multiple attributes (multi-dimensional data). Such networks present unique challenges to data dissemination, data storage of in-network information discovery. However, in order to fully exploit these networks for mission-critical applications, energy-efficient and scalable solutions for information discovery are essential. In this paper, we propose a novel and adaptive method for information discovery for multi-dimensional WSGs that can significantly increase network lifetime and minimize query processing latency, resulting in quality of service improvements that are of immense benefit to mission-critical applications. Further, we investigate efficient strategies for information discovery in large-scale wireless sensor networks and propose the Adaptive Multi-Dimensional Multi-Resolution Architecture (A-MDMRA) that efficiently combines “push” and “pull” strategies for information discovery. The A-MDMRA also adapts to variations in the frequencies of events and queries in the network to construct optimal routing structures. We present simulation results to show that the proposed approach to information discovery offers significant improvements on query resolution latency compared with current approaches. We observe that our proposed methods outperform existing schemes such as double rulings, comb needle and Time-Parameterized Data Centric Storage by up to 14% in terms of query resolution latency and up to 20% in terms of energy-efficiency.  相似文献   
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