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21.
Peter M. Bandelt Riess Jörg Engstle Michael Kuhn Heiko Briesen Petra Först 《化学工程与技术》2018,41(10):1956-1964
Packed beds used in absorption columns are evaluated to determine whether they can also be beneficial for cake‐forming filtrations. To assess this, model systems are characterized and separated by using a dead‐end filter cell. Filtrations are conducted with different packings; the filtrate amount over time and resulting turbidity are evaluated. Packings increase the filter cake resistance and the separation time of the cakes formed with approximately incompressible solids. However, they exhibit a positive effect on the filtration of a more complex, compressible substance; the process is not only accelerated, but also the quality of the obtained filtrate is not compromised. These results demonstrate potential in the use of packed beds for the filtration of complex biogenic suspensions. 相似文献
22.
Tesfaye?BayeEmail author Heiko?C.?Becker 《Journal of the American Oil Chemists' Society》2004,81(7):641-645
Vernonia galamensis is a potential new industrial oilseed crop from the Asteraceae family. The interest in this species is due to the presence
of a high vernolic acid content of its seed oil, which is useful in the oleochemical industry for paints and coatings. The
development of a rapid, precise, robust, nondestructive, and economical method to evaluate quality components is of major
interest to growers, processors, and breeders. NIR reflectance spectroscopy (NIRS) is routinely used for the prediction of
quality traits in many crops. This study was conducted to establish a rapid analytical method for determining the quality
of intact seeds of V. galamensis. A total of 114 Vernonia accessions were scanned to determine seed weight, FA composition, oil, and protein contents using NIRS. Conventional chemical
analysis for FA composition, total oil, and protein contents were performed by GC, Soxhlet extraction, and the Dumas combustion
method, respectively. Calibration equations were developed and tested through cross-validation. The coefficient of determination
in cross-validation for FA ranged from 0.47 (linoleic acid) to 0.55 (vernolic acid), and for oil, protein, and seed weight
from 0.71 (oil) to 0.86 (seed protein). It was concluded that NIRS calibration equations developed for seed weight and seed
quality traits can be satisfactorily used as early screening methods in V. galamensis breeding programs. 相似文献
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The neural mechanisms underlying motion segregation and integration still remain unclear to a large extent. Local motion estimates
often are ambiguous in the lack of form features, such as corners or junctions. Furthermore, even in the presence of such
features, local motion estimates may be wrong if they were generated near occlusions or from transparent objects. Here, a
neural model of visual motion processing is presented that involves early stages of the cortical dorsal and ventral pathways.
We investigate the computational mechanisms of V1-MT feedforward and feedback processing in the perception of coherent shape
motion. In particular, we demonstrate how modulatory MT-V1 feedback helps to stabilize localized feature signals at, e.g.
corners, and to disambiguate initial flow estimates that signal ambiguous movement due to the aperture problem for single
shapes. In cluttered environments with multiple moving objects partial occlusions may occur which, in turn, generate erroneous
motion signals at points of overlapping form. Intrinsic-extrinsic region boundaries are indicated by local T-junctions of
possibly any orientation and spatial configuration. Such junctions generate strong localized feature tracking signals that
inject erroneous motion directions into the integration process. We describe a simple local mechanism of excitatory form-motion
interaction that modifies spurious motion cues at T-junctions. In concert with local competitive-cooperative mechanisms of
the motion pathway the motion signals are subsequently segregated into coherent representations of moving shapes. Computer
simulations demonstrate the competency of the proposed neural model. 相似文献
26.
The controlled dispersion of fluids, particularly biologically relevant solutions in micro-volumes, is of high practical interest
in biotechnology and medicine. Pharmaceutical test assays, for example, need a method for the fast and defined deposition
of fluid samples. Most current micro-dispensing methods, i.e. contact-based pin printing, have problems such as time delays,
limited dosing velocity, minimum volume or high interference that limit biological applications. Spraying techniques suffer
from a lack of reproducibility; a defined deposition of samples on targets is not possible. Here, we introduce a new method
for the parallel and spatially defined dispersion of many micro-volumes that overcomes disadvantages of common micro-dispensers.
The overall approach is that a fluid drop, produced by a droplet generator, falls on a free trajectory with a defined kinetic
energy, and is split by a masking unit placed perpendicular to the flight direction into at least two smaller droplets (Zimmermann
et al. in Method and device for dosing fluid media, WO/2002/102515, Germany, 2002). On the target, the resulting droplets form reproducible patterns, which are enlarged and scalable images of the grid pattern.
Possible applications for this method are non-contact cell patterning, cell encapsulation, cryopreservation and fast mixing
processes in micro-volumes. Here, we use this method for the direct and defined parallel positioning of cell suspensions on
specific substrates, which can be useful for test assays, tissue engineering and cryopreservation. 相似文献
27.
María Cecilia Cimolai Silvia Alvarez Christoph Bode Heiko Bugger 《International journal of molecular sciences》2015,16(8):17763-17778
Sepsis is the manifestation of the immune and inflammatory response to infection that may ultimately result in multi organ failure. Despite the therapeutic strategies that have been used up to now, sepsis and septic shock remain a leading cause of death in critically ill patients. Myocardial dysfunction is a well-described complication of severe sepsis, also referred to as septic cardiomyopathy, which may progress to right and left ventricular pump failure. Many substances and mechanisms seem to be involved in myocardial dysfunction in sepsis, including toxins, cytokines, nitric oxide, complement activation, apoptosis and energy metabolic derangements. Nevertheless, the precise underlying molecular mechanisms as well as their significance in the pathogenesis of septic cardiomyopathy remain incompletely understood. A well-investigated abnormality in septic cardiomyopathy is mitochondrial dysfunction, which likely contributes to cardiac dysfunction by causing myocardial energy depletion. A number of mechanisms have been proposed to cause mitochondrial dysfunction in septic cardiomyopathy, although it remains controversially discussed whether some mechanisms impair mitochondrial function or serve to restore mitochondrial function. The purpose of this review is to discuss mitochondrial mechanisms that may causally contribute to mitochondrial dysfunction and/or may represent adaptive responses to mitochondrial dysfunction in septic cardiomyopathy. 相似文献
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Leonardo Candela Fuat Akal Henri Avancini Donatella Castelli Luigi Fusco Veronica Guidetti Christoph Langguth Andrea Manzi Pasquale Pagano Heiko Schuldt Manuele Simi Michael Springmann Laura Voicu 《International Journal on Digital Libraries》2007,7(1-2):59-80
This paper introduces DILIGENT, a digital library infrastructure built by integrating digital library and Grid technologies and resources. This infrastructure
allows different communities to dynamically build specialised digital libraries capable to support the entire e-Science knowledge
production and consumption life-cycle by using shared computing, storage, content, and application resources. The paper presents
some of the main software services that implement the DILIGENT system. Moreover, it exemplifies the provided features by presenting how the DILIGENT infrastructure is being exploited in supporting the activity of user communities working in the Earth Science Environmental
sector.
This work is partially funded by the European Commission in the context of the DILIGENT project, under the 2nd call of FP6 IST priority. 相似文献
30.
P. K. Chaviaropoulos I. G. Nikolaou K. A. Aggelis N. N. Soerensen J. Johansen M. O. L. Hansen Mac Gaunaa T. Hambraus Heiko Frhr. von Geyr Ch. Hirsch Kang Shun S. G. Voutsinas G. Tzabiras Y. Perivolaris S. Z. Dyrmose 《风能》2003,6(4):365-385
Aerodynamic modelling of HAWT rotors by means of “engineering methods” has reached a saddle point, where no further development can be expected without a breakthrough in understanding the physics of unsteady, rotating three‐dimensional flows. However, such a breakthrough becomes ever more necessary, as the size of the wind turbines increases. With the experimental work in that direction being mostly limited to observing the phenomena and interpreting the associated mechanisms, and its increased cost, alternatives are being sought. The use of CFD techniques and state‐of‐the‐art Navier–Stokes solvers is considered a very serious contender, a belief shared by the members of the present consortium, which has worked on the VISCEL JOR3‐CT98‐0208 Joule III project. This project's goal was to determine the aerodynamic characteristics as well as the aeroelastic behaviour of wind turbine blades across their broad range of operational conditions, from attached to highly separated flow regimes. The work programme included specific tasks for the validation and assessment of existing 3D solvers, for the parametric study of 3D flow around realistic blades and for the investigation of aeroelastic stability, at the blade section level. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献