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71.
Sabine Heublein Doris Mayr Klaus Friese Maria Cristina Jarrin-Franco Miriam Lenhard Artur Mayerhofer Udo Jeschke 《International journal of molecular sciences》2014,15(9):15161-15172
Ovarian granulosa cell tumors (GCTs) are thought to arise from cells of the ovarian follicle and comprise a rare entity of ovarian masses. We recently identified the G-protein-coupled estrogen receptor (GPER/GPR30) to be present in granulosa cells, to be regulated by gonadotropins in epithelial ovarian cancer and to be differentially expressed throughout folliculogenesis. Thus, supposing a possible role of GPER in GCTs, this study aimed to analyze GPER in GCTs. GPER immunoreactivity in GCTs (n = 26; n (primary diagnosis) = 15, n (recurrence) = 11) was studied and correlated with the main clinicopathological variables. Positive GPER staining was identified in 53.8% (14/26) of GCTs and there was no significant relation of GPER with tumor size or lymph node status. Those cases presenting with strong GPER intensity at primary diagnosis showed a significant reduced overall survival (p = 0.002). Due to the fact that GPER is regulated by estrogens, as well as gonadotropins, GPER may also be affected by endocrine therapies applied to GCT patients. Moreover, with our data supposing GPER to be associated with GCT prognosis, GPER might be considered as a possible confounder when assessing the efficacy of hormone-based therapeutic approaches in GCTs. 相似文献
72.
Programmers today face a bewildering array of parallel programming models and tools, making it difficult to choose an appropriate one for each application. An increasingly popular programming model supporting structured parallel programming patterns in a portable and composable manner is the task‐centric programming model. In this study, we compare several popular task‐centric programming frameworks, including Cilk Plus, Threading Building Blocks, and various implementations of OpenMP 3.0. We have analyzed their performance on the Barcelona OpenMP Tasking Suite benchmark suite both on a 48‐core AMD Opteron 6172 server and a 64‐core TILEPro64 embedded many‐core processor. Our results show that the OpenMP offers the highest flexibility for programmers, and this flexibility comes to a cost. Frameworks supporting only a specific and more restrictive model, such as Cilk Plus and Threading Building Blocks, are generally more efficient both in terms of performance and energy consumption. However, Intel's implementation of OpenMP tasks performs the best and closest to the specialized run‐time systems. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
73.
Leveraging the Ambipolar Transport in Polymeric Field‐Effect Transistors via Blending with Liquid‐Phase Exfoliated Graphene
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74.
Artur GUTKOWSKI 《热科学学报(英文版)》2006,(2)
Following the quantitative determination of dust cloud parameters, this study investigated the flame propagation through cornstarch dust clouds in a vertical duct of 780 mm height and 160×160 mm square cross section, and gave particular attention to the effect of turbulence on flame characteristics. The turbulence induced by dust dispersion process was measured using a particle image velocimetry (PIV) system. Upward propagating dust flames were visualized with direct light and shadow photography. The results show that a critical value of the turbulence intensity can be specified below which laminar flame propagation would be established. This transition condition is about 10 cm/s. The measured propagation speed of laminar flames appears to be in the range of 0.45-0.56 m/s, consistent with the measurements reported in the literature. For the present experimental conditions, the flame speed is little sensitive to the variations in dust concentration. Some information on the flame structure was revealed from the shadow records, showing the typical heterogeneous feature of dust combustion process. 相似文献
75.
Maria?Elena?LeyvaEmail author Filiberto?González?Garcia Alvaro?Antonio?Alencar?de?Queiroz Demétrio?Artur?Werner?Soares 《Journal of Materials Science: Materials in Electronics》2011,22(4):376-383
The metallopolymer polyaniline-silver (PANI-Ag) was synthesized and used as conductive filler in crosslinked diglycidyl ether
of bisphenol A (DGEBA) epoxy network. The hybrid organic/inorganic PANI-Ag powders were successfully synthesized via in situ
chemical oxidation of polyaniline-emeraldine base (PANI-EB) by the capped Ag+ on the polyaniline-emeraldine base (PANI-EB) surface. The UV–Vis and FT-IR spectra confirmed the pernigraniline structure
(PN) of PANI in the hybrid PANI-Ag. The PANI-Ag dispersion in epoxidic matrix was analyzed by optical microscopy (OM). The
images analysis from OM showed that the particle agglomerate size of the metallopolymer increased with increasing PANI-Ag
concentration in the DGEBA composite, owing to the aggregation effect. The dc conductivity and impedance spectroscopy of the
DGEBA/PANI-Ag composite was measured at different PANI-Ag concentrations in the DGEBA network. The electrical dc conductivity
of the PANI-Ag was 35.1 S cm−1 and was dependent of the PANI-Ag concentration in DGEBA matrix. The real and imaginary part of impedance complex measurements
indicates a strong interfacial polarization at low frequency for both PANI-Ag and DGEBA/PANI-Ag, respectively. The imaginary
part of impedance complex Im(Z) data decrease with the PANI-Ag hybrid concentration in the frequencies range of 102–106 Hz. The dependence of the Im(Z) on the frequency exhibited a relaxation process in both, PANI-Ag and DGEBA/PANI-Ag composite with 10 phr of PANI-Ag powder. 相似文献
76.
Artur Pinski Alexander Betekhtin Jolanta Kwasniewska Lukasz Chajec Elzbieta Wolny Robert Hasterok 《International journal of molecular sciences》2021,22(14)
As cell wall proteins, the hydroxyproline-rich glycoproteins (HRGPs) take part in plant growth and various developmental processes. To fulfil their functions, HRGPs, extensins (EXTs) in particular, undergo the hydroxylation of proline by the prolyl-4-hydroxylases. The activity of these enzymes can be inhibited with 3,4-dehydro-L-proline (3,4-DHP), which enables its application to reveal the functions of the HRGPs. Thus, to study the involvement of HRGPs in the development of root hairs and roots, we treated seedlings of Brachypodium distachyon with 250 µM, 500 µM, and 750 µM of 3,4-DHP. The histological observations showed that the root epidermis cells and the cortex cells beneath them ruptured. The immunostaining experiments using the JIM20 antibody, which recognizes the EXT epitopes, demonstrated the higher abundance of this epitope in the control compared to the treated samples. The transmission electron microscopy analyses revealed morphological and ultrastructural features that are typical for the vacuolar-type of cell death. Using the TUNEL test (terminal deoxynucleotidyl transferase dUTP nick end labelling), we showed an increase in the number of nuclei with damaged DNA in the roots that had been treated with 3,4-DHP compared to the control. Finally, an analysis of two metacaspases’ gene activity revealed an increase in their expression in the treated roots. Altogether, our results show that inhibiting the prolyl-4-hydroxylases with 3,4-DHP results in a vacuolar-type of cell death in roots, thereby highlighting the important role of HRGPs in root hair development and root growth. 相似文献
77.
This article is concerned with an artificial neural system for a mobile robot reactive navigation in an unknown, cluttered environment. Reactive navigation is a process of immediately choosing locomotion actions in response to measured spatial situations, while no planning occurs. A task of a presented system is to provide a steering angle signal letting a robot reach a goal while avoiding collisions with obstacles. Basic reactive navigation methods are briefly characterized, special attention is paid to a neural approach to the considered problem. The authors describe the system's architecture and important details of the algorithm. The main parts of the system are: the Fuzzy ART neural self-organizing classifier, performing a perceptual space partitioning, and a neural associative memory, memorizing the system's experience and superposing influences of different behaviors. Tests show that the learning process, starting from zero, is efficient, despite some initial fluctuations of its effectiveness. 相似文献
78.
Lea Heikinheimo Arja Miettinen‐Oinonen Artur Cavaco‐Paulo Johanna Buchert 《应用聚合物科学杂志》2003,90(7):1917-1922
The mode of action of monocomponent purified Trichoderma reesei cellobiohydrolases (CBHI and CBHII) and endoglucanases (EGI and EGII) on cotton fabrics was studied by analyzing the weight loss of the fabric, the reducing sugars, the soluble oligosaccharides and the molecular weight of the cotton powder formed. The impact of mechanical action on these factors was also evaluated. EGI and EGII released the highest amounts of reducing sugars and soluble oligosaccharides in both treatments with or without additional mechanical action. After cellulase treatment without additional mechanical action, all of the cellulases were found to have reduced the molecular weight of cotton poplin powder. When mechanical action was combined with enzyme treatments, only EGII reduced the molecular weight. The weight loss of EG‐treated fabrics was clearly higher than the weight loss of CBH‐treated fabrics with both low and high mechanical action levels. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1917–1922, 2003 相似文献
79.
Artur Manuel Ribeiro dos Santos Caldas de Matos Reiji Suzuki Takaya Arita 《Artificial Life and Robotics》2007,11(2):175-182
Recent studies in evolutionary computation have focused on using developmental processes together with genetic algorithms
in order to achieve more complex designs. Although several models have been proposed, their growth dynamics, and their interactions
with evolutionary algorithms are still poorly understood. One particularly neglected concept in artificial developmental systems
is heterochrony: how evolution affects development by changing the timing and rate of developmental events. In this article we attempt to
address this issue by analyzing heterochronic changes in a well-known artificial developmental model, the cellular encoding
model, by using a previously developed heterochrony framework. We have conducted experiments by evolving networks to solve
a Boolean problem, and analyzed heterochronic changes in both successful and unsuccessful runs. Our findings show that owing
to its properties, the cellular encoding model strongly affects the developmental dynamics and the heterochronic changes that
occur during evolution. Our experiments also show that hypermorphic changes (a kind of heterochronic occurrence) lead to greater
evolvability in successful runs. 相似文献
80.
Hydrodynamische Einlauflänge und Widerstandsgesetz von reibungsmindernden kationschen Tensidlösungen
Dipl.-Ing. Hans-Heinrich Kleuker cand. ing. Anke Laurenzis Dr.-Ing. Wilhelm Althaus Dr.-Ing. Artur Steiff Prof. Dr.-Ing. Paul-Michael Weinspach 《Forschung im Ingenieurwesen》1993,59(1-2):8-18
Zusammenfassung Durch Zugabe geeigneter Tensidsysteme in Wasser kann der Str?mungsdruckverlust in geraden Rohren erheblich gesenkt werden.
Die diesem Effekt zugrunde liegenden Mechanismen wurden in früheren Arbeiten eingehend diskutiert. In dieser Arbeit werden
neue Ergebnisse vorgestellt, die sowohl die Bestimmung der hydrodynamischen Einlaufl?nge als auch die Ermittlung der Widerstandsbeiwerte
im ausgebildeten Str?mungszustand erm?glichen. Für den Bereich der ausgebildeten Rohrstr?mung wird eine neue Berechnungsgleichung
vorgeschlagen. Durch Erweiterung der bisherigen Modellvorstellungen ergibt sich ein Widerstandsgesetz für den gesamten Wirkungsbereich
des Tensids. Die Ergebnisse stützen sich auf Untersuchungen mit zwei verschiedenen Additivsystemen, bei denen die Parameter
Str?mungsgeschwindigkeit, Temperatur und Einsatzkonzentration variiert wurden. 相似文献