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71.
Jonathan Pieper 《Annals of Mathematics and Artificial Intelligence》2018,84(1-2):17-33
This paper describes the team BusyBeaver, that participated in and won the Multi-Agent Programming Contest 2017. Its strategy is based on dividing agents into three static groups modeling the work chain of buying, assembling and delivering items. The team is coordinated by a centralized agent doing most of the high-level planning, usually using greedy algorithms and specialized heuristics. There is a heavy focus on proactively buying and assembling some items, in order to quickly complete upcoming jobs. 相似文献
72.
73.
Pei Y Yu H Pei Z Theurer M Ammer C André S Gabius HJ Yan M Ramström O 《Analytical chemistry》2007,79(18):6897-6902
Photoderivatized polymer-coated gold surfaces have been developed following a perfluorophenylazide-based double ligation strategy. Gold-plated quartz crystal microbalance (QCM) crystals were initially covalently functionalized with a monolayer of poly(ethylene glycol) (PEG), using photo- or thermolytic nitrene formation and insertion. The polymer surfaces were subsequently used as substrates for photoinsertion of carbohydrate-derivatized photoprobes, yielding different recognition motifs for selective protein binding. The resulting robust and biocompatible sensor surfaces were applied to a flow-through QCM instrument for monitoring lectin-carbohydrate interactions in real time. The results clearly show the predicted lectin selectivity, demonstrating the applicability of the approach. 相似文献
74.
Franziska Gsottberger Carolin Brandl Kerstin Wendland Srdjan Petkovic Charlotte Emmerich Ramona Erber Carol Geppert Arndt Hartmann Andreas Mackensen Lars Nitschke Fabian Müller 《International journal of molecular sciences》2021,22(19)
Targeted immunotherapies have greatly changed treatment of patients with B cell malignancies. To further enhance immunotherapies, research increasingly focuses on the tumor microenvironment (TME), which differs considerably by organ site. However, immunocompetent mouse models of disease to study immunotherapies targeting human molecules within organ-specific TME are surprisingly rare. We developed a myc-driven, primary murine lymphoma model expressing a human-mouse chimeric CD22 (h/mCD22). Stable engraftment of three distinct h/mCD22+ lymphoma was established after subcutaneous and systemic injection. However, only systemic lymphoma showed immune infiltration that reflected human disease. In this model, myeloid cells supported lymphoma growth and showed a phenotype of myeloid-derived suppressor cells. The human CD22-targeted immunotoxin Moxetumomab was highly active against h/mCD22+ lymphoma and similarly reduced infiltration of bone marrow and spleen of all three models up to 90-fold while efficacy against lymphoma in lymph nodes varied substantially, highlighting relevance of organ-specific TME. As in human aggressive lymphoma, anti-PD-L1 as monotherapy was not efficient. However, anti-PD-L1 enhanced efficacy of Moxetumomab suggesting potential for future clinical application. The novel model system of h/mCD22+ lymphoma provides a unique platform to test targeted immunotherapies and may be amenable for other human B cell targets such as CD19 and CD20. 相似文献
75.
In this paper, a discrete‐time piecewise affine (PWA) model of a wind turbine during Maximum Power Point Tracking (MPPT) region is identified. A clustering‐based identification method is utilized to create PWA maps for nonlinear aerodynamic torque and thrust force functions. This method exploits the combined use of clustering, pattern recognition, and parameter identification techniques. The well‐known K‐means clustering method is employed along with a perceptron‐based multiclassifier for pattern recognition and the least squared technique for parameter estimation. The identified maps are approximated the nonlinear static functions of the dynamic model of the wind turbine. Characteristics of a 5‐MW wind turbine are considered and the resulting model, which consists of 25 subregions is compared with the nonlinear dynamic model. Two test cases are studied in order to validate the presented model. Simulation results demonstrate the effectiveness and accuracy of the PWA model such that the response of the identified PWA model is fitted well to the nonlinear one. The PWA model identified in this paper can be widely used for advanced control systems design and long‐term performance and security assessment of the power grid. 相似文献
76.
Blackcurrant pomace from juice processing as partial flour substitute in savoury crackers: dough characteristics and product properties
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Carolin Schmidt Insa Geweke Susanne Struck Susann Zahn Harald Rohm 《International Journal of Food Science & Technology》2018,53(1):237-245
Berry pomace is a by‐product of juice processing that, after drying and milling, may be used as an ingredient in cereal‐based products. This, on the one hand, not only reduces losses of edible raw material components, but also increases the nutritional value of the target food because of its high dietary fibre and bioactive compounds content. By using savoury crackers as model, this study analyses how a partial flour replacement by blackcurrant pomace (levels: 10%, 20% or 30%) affects physical properties of the respective dough (dynamic rheology in simulated baking, extensibility and adhesiveness) and characteristics of the baked product (colour, texture and sensory properties). Pomace addition significantly affected both systems. By considering the high moisture absorption capacity of this material through water level adaptation in formulations and by only substituting gluten‐free flour (which led to a constant gluten content), it is demonstrated that even a flour replacement of up to 30% leads to acceptable products. A restrained protein development was observed in pomace containing dough, leading to a lower extensibility, and to reduced volume increase and lower breaking force after baking. In contrast, dough handling and sensory acceptance were not corrupted by pomace application even though colour of the final product was changed to a great extent. 相似文献
77.
Carolin Fischer Geir I. Vestøl Audun Øvrum Olav A. Høibø 《Holz als Roh- und Werkstoff》2018,76(3):899-909
The aim of the study was to assess site effects in terms of unexplained site variance in machine strength grading of Norway spruce structural timber. The site effects were estimated for grading based on axial resonance frequency and timber length, and for grading based on dynamic modulus of elasticity. Timber was collected from 14 sites in Norway, and linear mixed models were developed based on 1188 boards. The study showed that strength grading based on axial resonance frequency and timber length leaves out effects of site that are related to altitude, latitude and site index. The variance could be reduced when the grading was based on dynamic modulus of elasticity. For both grading methods, the site effects were smaller for bending strength than for modulus of elasticity and density. Major parts of the site effects were explained by mass density, and simulations showed that it is possible to fulfil the requirements of the strength classes with a higher yield when the sorting is based on a combination of exclusion by mass density and exclusion by the frequency-based indicating property. 相似文献
78.
W. T. Wondmagegn N. T. Satyala R. J. Pieper M. A. Quevedo-Lopez S. Gowrisanker H. N. Alshareef H. J. Stiegler B. E. Gnade 《Journal of Computational Electronics》2011,10(1-2):144-153
The contact resistance of field effect transistors based on pentacene and parylene has been investigated by experimental and numerical analysis. The device simulation was performed using finite element two-dimensional drift-diffusion simulation taking into account field-dependent mobility, interface/bulk trap states and fixed charge density at the organic/insulator interface. The width-normalized contact resistance extracted from simulation which included an interface dipole layer between the gold source/drain electrodes and pentacene was 91 k??cm. However, contact resistance extracted from the simulation, without consideration of interface dipole was 52.4?k??cm, which is about half of the experimentally extracted 108?k??cm. This indicates that interface dipoles are critical effects which degrade performances of organic field effect transistors by increasing the contact resistance. Using numerical calculations and circuit simulations, we have predicted a 1?MHz switching frequency for a 1???m channel length transistor without dipole interface between gold and pentacene. The transistor with dipole interface is predicted, via the same methods, to exhibit an operating frequency of less than 0.5?MHz. 相似文献
79.
Carolin Wang-Hansen Per Ericsson Björn Lundberg Magnus Skoglundh Per-Anders Carlsson Bengt Andersson 《Topics in Catalysis》2013,56(1-8):446-451
The reactivity and reaction kinetics of particulate matter (PM) from direct injected gasoline (GDI) engines has been studied by O2 and NO2 based temperature programmed and isothermal step-response experiments, and the PM nano-structure has been characterized using HRTEM. The reactivity of the PM samples collected in filters during on-road driving was found to increase in the following order: Printex U < diesel < gasoline PI ≈ gasoline DI < ethanol for O2 based combustion. The activation energies for O2 and NO2 based oxidation of PM collected from a GDI engine in an engine bench set-up was estimated to 146 and 71 kJ/mol respectively, which is comparable to corresponding values reported for diesel and model soot. Similar nano-structure features (crystallites plane dimensions, curvature and relative orientation) as observed for diesel soot were observed for gasoline PM. 相似文献
80.
M. Hassan Beyzavi Carolin Nietzold Hans‐Ulrich Reissig Arno Wiehe 《Advanced Synthesis \u0026amp; Catalysis》2013,355(7):1409-1422
meso‐Substituted trans‐A2B2‐porphyrins bearing specific patterns of substituents are crucial building blocks in porphyrin‐based biomimetic systems and molecular materials and can be used for the construction of well‐defined porphyrin‐based architectures. A new stepwise and rational synthesis of functionalized trans‐A2B2‐porphyrins is reported in which for the first time donor–acceptor‐substituted cyclopropane precursors (d–a cyclopropanes) are exploited. The three presented d–a cyclopropanes are readily accessible in a multi‐gram scale and serve as aldehyde equivalents in the reaction with an excess of pyrrole to afford the corresponding dipyrromethanes (DPMs). The three DPMs were synthesized in yields of 60–74%. They are stable in purified form in the absence of light and air and were subsequently condensed with a wide range of aliphatic and aromatic aldehydes bearing electron‐donating or electron‐withdrawing substituents followed by oxidation to form the corresponding trans‐A2B2‐porphyrins. Fourteen functionalized porphyrins were synthesized in yields of 14–31%, indicating the broad scope of the synthetic procedure. The possibility to introduce key functional groups is emphasized, which enables subsequent modification of these porphyrins with moieties inducing biological activity. Modification of the tetrapyrroles may occur by addition to one of the porphyrin peripheral double bonds, the use of substituents of the aryl groups or via the methoxycarbonyl group at two of the meso‐substituents. Three examples of porphyrins were converted into the corresponding 7,8‐dihydroxychlorins by osmium‐mediated dihydroxylation and one of the resulting chlorins was subjected to saponification to give a highly polar chlorin dicarboxylic acid. A 4‐bromophenyl‐substituted d–a cyclopropane was prepared by rhodium‐catalyzed cyclopropanation and then transformed into a DPM which was subsequently condensed to a porphyrin. Its Zn complex allowed a Heck reaction to afford the functionalized bis(alkenyl)‐substituted trans‐A2B2‐Zn‐porphyrin. 相似文献