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101.
    
This study examines the viability of using additively manufactured injection molding tools for short run proof‐of‐concept plastic parts by assessing the quantity and quality of molded parts. Prototyping injection molded parts traditionally can be very expensive, but with improved additive manufacturing materials and techniques such costs could be reduced. To prove this, plastic tools were made by using PolyJet and Fused Deposition Modeling out of Digital ABS, FullCure 720, and ULTEM 1010 materials in this study. The test tools were then compared to the standard P20 metal tool by molding acetal, polycarbonate (PC), and polypropylene (PP) in each tool type. The molded parts were analyzed for processing effects on part shrink, physical, and mechanical properties. Testing concluded that parts molded with additively manufactured tools performed comparably to parts made on a P20 tool. However, the quantity of satisfactory parts molded in acetal and PC were consistent with the literature at 10–100 parts. Conversely, molding in PP suggested that processing with additive manufactured tools could exceed 250 parts. POLYM. ENG. SCI., 59:1911–1918, 2019. © 2019 Society of Plastics Engineers  相似文献   
102.
    
The use of mixed-matrix materials (MMM) has become a major topic of research in recent years, due to unique properties achieved in these composites. In this work, biochar from sunflower seed hull pyrolysis and biochar/polysulfone (PSF) MMMs were produced and characterized. The optimal pyrolysis temperature for biochar production was determined to be 500 °C. The resulting biochar properties were an iodine number of 203 mg/g and a pore volume of 0.595 mL/g. In MMM fabrication, the use 4% ethanol as nonsolvent in the wet phase inversion process increased the glass transition temperature by 8 °C, indicating improved biochar/PSF interaction. The presence of biochar was shown to create pores in otherwise dense surfaces. The critical surface energy was also increased by the addition of biochar from 28.6 mN/m in pristine PSF to 35.7 mN/m in biochar/PSF MMMs. We identified and discussed several potential applications based on the determined properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48027.  相似文献   
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Photodetectors with broadband detection capability are desirable for sensing applications in the coming age of the internet‐of‐things. Although 2D layered materials (2DMs) have been actively pursued due to their unique optical properties, by far only graphene and black arsenic phosphorus have the wide absorption spectrum that covers most molecular vibrational fingerprints. However, their reported responsivity and response time are falling short of the requirements needed for enabling simultaneous weak‐signal and high‐speed detections. Here, a novel 2DM, black phosphorous carbide (b‐PC) with a wide absorption spectrum up to 8000 nm is synthesized and a b‐PC phototransistor with a tunable responsivity and response time at an excitation wavelength of 2004 nm is demonstrated. The b‐PC phototransistor achieves a peak responsivity of 2163 A W?1 and a shot noise equivalent power of 1.3 fW Hz?1/2 at 2004 nm. In addition, it is shown that a response time of 0.7 ns is tunable by the gating effect, which renders it versatile for high‐speed applications. Under the same signal strength (i.e., excitation power), its performance in responsivity and detectivity in room temperature condition is currently ahead of recent top‐performing photodetectors based on 2DMs that operate with a small bias voltage of 0.2 V.  相似文献   
105.
We report a set of brominated luciferins for bioluminescence imaging. These regioisomeric scaffolds were accessed by using a common synthetic route. All analogues produced light with firefly luciferase, although varying levels of emission were observed. Differences in photon output were analyzed by computation and photophysical measurements. The brightest brominated luciferin was further evaluated in cell and animal models. At low doses, the analogue outperformed the native substrate in cells. The remaining luciferins, although weak emitters with firefly luciferase, were inherently capable of light production and thus potential substrates for orthogonal mutant enzymes.  相似文献   
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107.
Degraders have illustrated that compound-induced proximity to E3 ubiquitin ligases can prompt the ubiquitination and degradation of disease-relevant proteins. Hence, this pharmacology is becoming a promising alternative and complement to available therapeutic interventions (e. g., inhibitors). Degraders rely on protein binding instead of inhibition and, hence, they hold the promise to broaden the druggable proteome. Biophysical and structural biology approaches have been the cornerstone of understanding and rationalizing degrader-induced ternary complex formation. Computational models have now started to harness the experimental data from these approaches with the aim to identify and rationally help design new degraders. This review outlines the current experimental and computational strategies used to study ternary complex formation and degradation and highlights the importance of effective crosstalk between these approaches in the advancement of the targeted protein degradation (TPD) field. As our understanding of the molecular features that govern drug-induced interactions grows, faster optimizations and superior therapeutic innovations for TPD and other proximity-inducing modalities are sure to follow.  相似文献   
108.
This research investigated the effects of current density and sulfuric acid concentration on the rates of persulfate generation by boron-doped diamond film anodes. Also investigated was the maximum conversion of sulfate to persulfate that could be achieved from electrolysis of sulfuric acid. Experiments were performed in batch systems using a rotating disk electrode (RDE) and a flow-through reactor with parallel plate electrodes. Both the RDE and flow-through experiments showed that there was a linear relationship between persulfate generation rates and current density. Persulfate generation rates became current limited at sulfuric acid concentrations of 2.25 M and above; however, Faradaic efficiencies under current-limited conditions were only ~60 %, and were only weakly dependent on the current density. Persulfate generation rates in the flow-through reactor showed similar dependencies on current density and sulfuric acid concentration as those in the RDE reactor, but were 20–50 % lower. Acid catalyzed and thermal decomposition of persulfate limited the maximum conversion of sulfate to persulfate. A maximum fractional conversion of 78 % was achieved using an initial sulfuric acid concentration of 0.77 M. Surprisingly, this value was independent of the current density over the range of 100–300 mA cm?2.  相似文献   
109.
Describes the Developmental Inventory of Black Consciousness (DIB-C). Empirical, theoretical, autobiographical, and biographical studies suggest there are 4 distinct stages of Black consciousness: the preconscious stage, confrontation, internalization, and integration. Items were written for each of these domains and administered to 160 Black male undergraduates. The DIB-C was analyzed by using a sequentially organized psychometric strategy of item discrimination and tests of homogeneity, social desirability, and differential validity. A construct validational study was also performed using the unpublished "Nadanolitization Scale," which measures the degree of internalization by Blacks of stereotypic attitudes held by Whites about Blacks. Results show 65 items remaining for the DIB-C following the sequential analysis. Construct validation showed an inverse linear relationship between the degree of "Nadanolitization" and progressive DIB-C scores. Psychotherapeutic implications are discussed. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
We present an on-shot focal-spot characterization technique based on a phase-retrieval scheme that retrieves near-field phase from multiplane focal-spot measurements in an experimental target chamber. The technique is easy to implement inside a target chamber and is demonstrated in a multiterawatt laser system. It is also found that phase retrieval can quantitatively detect residual angular dispersion coming from the pulse compressor misalignment.  相似文献   
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