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1.
2.
We demonstrate that alkali-halide salts, particularly potassium bromide, can reduce the photothermal emission (PTE) from single walled carbon nanotubes (SWNT). PTE is a prominent spectral feature in Raman spectroscopy when a near infrared laser is used to analyze a dark colored sample. We subsequently show that trapping salts inside SWNT and coating SWNT with the salt has a more pronounced impact on not only reducing PTE, but also enhancing the intensity of the Raman spectral features. The effect, which we have called nanotube enhanced Raman spectroscopy (NERS), has differences and similarities to the widely studied surface enhanced Raman spectroscopy (SERS). 相似文献
3.
Jarvis Tyler Clough Jordan Cox Jane Petersen Konnor Sailsbery Mitchell Robertson Connor Moncur Tyler Palmer Katie Lund Darren 《Water Resources Management》2021,35(2):745-756
Water Resources Management - A traditional cost-benefit analysis of potential water interventions in a given locality is a laborious and time-intensive process. To help decision makers identify... 相似文献
4.
Trevor Bench-Capon Katie Atkinson Peter McBurney 《Autonomous Agents and Multi-Agent Systems》2012,25(1):183-208
In this paper we demonstrate how a qualitative framework for decision making can be used to model scenarios from experimental
economic studies and we show how our approach explains the results that have been reported from such studies. Our framework
is an argumentation-based one in which the social values promoted or demoted by alternative action options are explicitly
represented. Our particular representation is used to model the Dictator Game and the Ultimatum Game, which are simple interactions
in which it must be decided how a sum of money will be divided between the players in the games. Studies have been conducted
into how humans act in such games and the results are not explained by a decision-model that assumes that the participants
are purely self-interested utility-maximisers. Some studies further suggest that differences in choices made in different
cultures may reflect their day to day behaviour, which can in turn be related to the values of the subjects, and how they
order their values. In this paper we show how these interactions can be modelled in agent systems in a framework that makes
explicit the reasons for the agents’ choices based upon their social values. Our framework is intended for use in situations
where agents are required to be adaptable, for example, where agents may prefer different outcome states in transactions involving
different types of counter-parties. 相似文献
5.
Amirah Mohammad-Sidik Jian Sun Ryoung Shin Zhizhong Song Youzheng Ning Elsa Matthus Katie A. Wilkins Julia M. Davies 《International journal of molecular sciences》2021,22(2)
Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca2+ ([Ca2+]cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca2+ influx channels involved in eATP-induced [Ca2+]cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca2+ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca2+]cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes. 相似文献
6.
Clara Mata Ellen K. Longmire David H. McKenna Katie K. Glass Allison Hubel 《Microfluidics and nanofluidics》2008,5(4):529-540
A recently proposed application of microfluidics is the post-thaw processing of biological cells. Numerical simulations suggest
that diffusion-based extraction of the cryoprotective agent dimethyl sulfoxide (DMSO) from blood cells is viable and more
efficient than centrifugation, the conventional method of DMSO removal. In order to validate the theoretical model used in
these simulations, a prototype was built and the flow of two parallel streams, a suspension of Jurkat cells containing DMSO
and a wash stream that contained neither cells nor DMSO, was characterized experimentally. DMSO transport in a rectangular
channel (depth 500 μm, width 25 mm and overall length 125 mm) was studied as a function of three dimensionless parameters:
depth ratio of the streams, cell volume fraction in the cell solution, and the Peclet number (Pe) based on channel depth, average flow rate and the diffusion coefficient for DMSO in water. In our studies, values of Pe ranged from O(103) to O(104). Laminar flow was ensured by keeping the Reynolds number between O(1) and O(10). Experimental results based on visual and
quantitative data demonstrate conclusively that a microfluidic device can effectively remove DMSO from liquid and cell laden
streams without compromising cell recovery. Also, flow conditions in the microfluidic device appear to have no adverse effect
on cell viability at the outlet. Further, the results demonstrate that we can predict the amount of DMSO removed from a given
device with the theoretical model mentioned previously. 相似文献
7.
The temperature sensitivity of cross talk between closely spaced cores in a common cladding is calculated and compared with measurements. A periodic variation in core contrast is observed when one core is illuminated and the temperature is changed. The variation in light distribution, which is ascribable to a change in coupling between the cores, agrees with theoretical predictions. It is shown that cross talk can be made to be a sensitive, predictable function of temperature or by proper selection of materials, wavelength, and fiber geometry essentially temperature independent. 相似文献
8.
Exposure to foot-transmitted vibration (FTV) can lead to pain and numbness in the toes and feet, increased cold sensitivity, blanching in the toes, and joint pain. Prolonged exposure can result in a clinical diagnosis of vibration-induced white foot (VIWFt). Data on the biomechanical response of the feet to FTV is limited; therefore, this study seeks to identify resonant frequencies for different anatomical locations on the human foot, while standing in a natural position. A laser Doppler vibrometer was used to measure vertical (z-axis) vibration on 21 participants at 24 anatomical locations on the right foot during exposure to a sine sweep from 10–200?Hz with a peak vertical velocity of 30?mm/s. The most notable differences in the average peak frequency occur between the toes (range: 99–147?Hz), midfoot (range: 51–84?Hz) and ankle (range: 16–39?Hz).
Practitioner Summary: The biomechanical response of the human foot exposed to foot-transmitted vibration, when standing in a natural position, was measured for 21 participants. The foot does not respond uniformly; the toes, midfoot, and ankle regions need to be considered independently in future development of isolation strategies and protective measures. 相似文献
9.
D. Grant Willhite Jennifer R. Brigati Katie E. Selcer Joshua E. Denny Zachary A. Duck Stephen E. Wright 《Yeast (Chichester, England)》2014,31(9):361-374
Many fungi have evolved mechanisms to assess environmental nutrient availability prior to the energy‐intensive process of mating. In this study, we examined one such system in Saccharomyces cerevisiae, involving a glucose‐sensing pathway mediated by Gpr1p and the pheromone‐induced mating pathway. Initially we observed that the mating pathway in MATa cells is sensitive to environmental glucose depletion. This phenomenon can be partially reversed with a high glucose spike, but not with the addition of low levels of glucose. Deletion of the low‐affinity glucose receptor, Gpr1p, eliminated this glucose‐induced recovery of pheromone responsiveness. We then determined the impact of GPR1 deletion on the mating pathway and observed that, in all end points studied, the mating pathway response to pheromone is reduced in the absence of Gpr1p. Similarly, elimination of the Gα for Gpr1p, Gpa2p, resulted in reduction in pheromone sensitivity in all assays studied. The negative effect of removing Gpr1p on mating pathway activation could be recovered by overexpressing the mating receptor, Ste2p. Furthermore, Ste2p levels are reduced in the absence of glucose and GPR1. These data suggest that activity of the GPCR‐mediated mating pathway in S. cerevisiae is modulated by extracellular glucose concentrations through the only other GPCR in MATa cells, Gpr1p. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
10.