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991.
Silvia Pisani Enrica Chiesa Ida Genta Rossella Dorati Marilena Gregorini Maria Antonietta Grignano Marina Ramus Gabriele Ceccarelli Stefania Croce Chiara Valsecchi Manuela Monti Teresa Rampino Bice Conti 《International journal of molecular sciences》2022,23(14)
This work focuses on formulating liposomes to be used in isolated kidney dynamic machine perfusion in hypothermic conditions as drug delivery systems to improve preservation of transplantable organs. The need mainly arises from use of kidneys from marginal donors for transplantation that are more exposed to ischemic/reperfusion injury compared to those from standard donors. Two liposome preparation techniques, thin film hydration and microfluidic techniques, are explored for formulating liposomes loaded with two model proteins, myoglobin and bovine serum albumin. The protein-loaded liposomes are characterized for their size by DLS and morphology by TEM. Protein releases from the liposomes are tested in PERF-GEN perfusion fluid, 4 °C, and compared to the in vitro protein release in PBS, 37 °C. Fluorescent liposome uptake is analyzed by fluorescent microscope in vitro on epithelial tubular renal cell cultures and ex vivo on isolated pig kidney in hypothermic perfusion conditions. The results show that microfluidics are a superior technique for obtaining reproducible spherical liposomes with suitable size below 200 nm. Protein encapsulation efficiency is affected by its molecular weight and isoelectric point. Lowering incubation temperature slows down the proteins release; the perfusion fluid significantly affects the release of proteins sensitive to ionic media (such as BSA). Liposomes are taken up by epithelial tubular renal cells in two hours’ incubation time. 相似文献
992.
Martin Reichert Srebrena Atanasova Kathrin Petri Marian Kampschulte Baktybek Kojonazarov Gabriele Fuchs-Moll Gabriele A. Krombach Winfried Padberg Veronika Grau 《International journal of molecular sciences》2022,23(15)
Alloreactive and autoreactive antibodies have been associated with the development of chronic lung allograft dysfunction (CLAD), but their pathogenic role is disputed. Orthotopic left lung transplantation was performed in the Fischer-344 to Lewis rat strain combination followed by the application of ciclosporine for 10 days. Four weeks after transplantation, lipopolysaccharide (LPS) was instilled into the trachea. Lungs were harvested before (postoperative day 28) and after LPS application (postoperative days 29, 33, 40, and 90) for histopathological, immunohistochemical, and Western blot analyses. Recipient serum was collected to investigate circulating antibodies. Lung allografts were more strongly infiltrated by B cells and deposits of immunoglobulin G and M were more prominent in allografts compared to right native lungs or isografts and increased in response to LPS instillation. LPS induced the secretion of autoreactive antibodies into the circulation of allograft and isograft recipients, while alloreactive antibodies were only rarely detected. Infiltration of B cells and accumulation of immunoglobulin, which is observed in allografts treated with LPS but not isografts or native lungs, might contribute to the pathogenesis of experimental CLAD. However, the LPS-induced appearance of circulating autoreactive antibodies does not seem to be related to CLAD, because it is observed in both, isograft and allograft recipients. 相似文献
993.
von Helversen Bettina; Wilke Andreas; Johnson Tim; Schmid Gabriele; Klapp Burghard 《Canadian Metallurgical Quarterly》2011,120(4):962
Previous research reported conflicting results concerning the influence of depression on cognitive task performance. Whereas some studies reported that depression enhances performance, other studies reported negative or null effects. These discrepant findings appear to result from task variation, as well as the severity and treatment status of participant depression. To better understand these moderating factors, we study the performance of individuals—in a complex sequential decision task similar to the secretary problem—who are nondepressed, depressed, and recovering from a major depressive episode. We find that depressed individuals perform better than do nondepressed individuals. Formal modeling of participants' decision strategies suggested that acutely depressed participants had higher thresholds for accepting options and made better choices than either healthy participants or those recovering from depression. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
994.
Model transformation is one of the key activities in model-driven software development. An increasingly popular technology
to define modeling languages is provided by the Eclipse Modeling Framework (EMF). Several EMF model transformation approaches have been developed, focusing on different transformation
aspects. To validate model transformations with respect to functional behavior and correctness, a formal foundation is needed.
In this paper, we define consistent EMF model transformations as a restricted class of typed graph transformations using node
type inheritance. Containment constraints of EMF model transformations are translated to a special kind of graph transformation
rules such that their application leads to consistent transformation results only. Thus, consistent EMF model transformations
behave like algebraic graph transformations and the rich theory of algebraic graph transformation can be applied to these
EMF model transformations to show functional behavior and correctness. Furthermore, we propose parallel graph transformation
as a suitable framework for modeling EMF model transformations with multi-object structures. Rules extended by multi-object structures can specify a flexible number of recurring structures. The actual number of recurring
structures is dependent on the application context of such a rule. We illustrate our approach by selected refactorings of
simplified statechart models. Finally, we discuss the implementation of our concepts in a tool environment for EMF model transformations. 相似文献
995.
The paradigm of model-based software development has become more and more popular since it promises an increase in the efficiency and quality of software development. Following this paradigm, models become primary artifacts in the software development process. Therefore, software quality and quality assurance frequently leads back to the quality and quality assurance of the involved models. In our approach, we propose a model quality assurance process that can be adapted to project-specific and domain-specific needs. This process is based on static model analysis using model metrics and model smells. Based on the outcome of the model analysis, appropriate model refactoring steps can be performed. In this paper, we present a tool environment conveniently supporting the proposed model quality assurance process. In particular, the presented tools support metrics reporting, smell detection, and refactoring for models being based on the Eclipse Modeling Framework, a widely used open source technology in model-based software development. 相似文献
996.
997.
Erika Michela Dematteis Antonio Santoru Marco Gabriele Poletti Claudio Pistidda Thomas Klassen Martin Dornheim Marcello Baricco 《International Journal of Hydrogen Energy》2018,43(34):16793-16803
The present study aims at investigating, for the first time, a quinary mixture of light-metals borohydrides. The goal is to design combinations of borohydrides with multiple cations in equimolar ratio, following the concept of high entropy alloys. The equimolar composition of the LiBH4NaBH4KBH4Mg(BH4)2Ca(BH4)2 system was synthetized by ball milling. The obtained phases were analysed by X-ray diffraction and in-situ Synchrotron Radiation Powder X-ray Diffraction, in order to establish the amount of cations incorporated in the obtained crystalline phases and to study the thermal behaviour of the mixture. HP-DSC and DTA were also used to define the phase transformations and thermal decomposition reactions, leading to the release of hydrogen, that was detected by MS. The existence of a quinary liquid borohydride phase is reported for the first time. Effects of the presence of multi-cations compounds or a liquid phase on the hydrogen desorption reactions are described. 相似文献
998.
Hai-Bin MA Wei-Dong ZHUO Davide LAVORATO Camillo NUTI Gabriele FIORENTINO Giuseppe Carlo MARANO Rita GRECO Bruno BRISEGHELLA 《Frontiers of Structural and Civil Engineering》2019,13(6):1510
Performance-based seismic design can generate predictable structure damage result with given seismic hazard. However, there are multiple sources of uncertainties in the seismic design process that can affect desired performance predictability. This paper mainly focuses on the effects of near-fault pulse-like ground motions and the uncertainties in bridge modeling on the seismic demands of regular continuous highway bridges. By modeling a regular continuous bridge with OpenSees software, a series of nonlinear dynamic time-history analysis of the bridge at three different site conditions under near-fault pulse-like ground motions are carried out. The relationships between different Intensity Measure (IM) parameters and the Engineering Demand Parameter (EDP) are discussed. After selecting the peak ground acceleration as the most correlated IM parameter and the drift ratio of the bridge column as the EDP parameter, a probabilistic seismic demand model is developed for near-fault earthquake ground motions for 3 different site conditions. On this basis, the uncertainty analysis is conducted with the key sources of uncertainty during the finite element modeling. All the results are quantified by the “swing” base on the specific distribution range of each uncertainty parameter both in near-fault and far-fault cases. All the ground motions are selected from PEER database, while the bridge case study is a typical regular highway bridge designed in accordance with the Chinese Guidelines for Seismic Design of Highway Bridges. The results show that PGA is a proper IM parameter for setting up a linear probabilistic seismic demand model; damping ratio, pier diameter and concrete strength are the main uncertainty parameters during bridge modeling, which should be considered both in near-fault and far-fault ground motion cases. 相似文献
999.
Colours in cultural heritage are not only means of expression, but also materials with physical and chemical properties. Since the beginning of the current century, colorimetry has become a fundamental field aiming at restoring, preserving and valorising the art works. There are different colorimetric applications in cultural heritage (eg, from light design to digitisation and modelling), and the variety of cultural material is extremely wide, from statues and frescoes, to old book and films. In this heterogeneous context, the development of instruments, measurements and tools faithful to the original objects are fundamental to correctly reproducing and representing materials, contrast and colours of the works under analysis. In this work, we will analyse the main limits of colorimetry applied in cultural heritage domain considering a variety of applications on physical colour representation and on digital colour reproduction. We will focus on main state‐of‐the‐art studies, regulations and guidelines for objects illumination, colour analysis and digitisation workflow showing some practical example of issues encountered by standard pointwise colorimetry. 相似文献
1000.
Christopher J. Heard Jií ejka Maksym Opanasenko Petr Nachtigall Gabriele Centi Siglinda Perathoner 《Advanced materials (Deerfield Beach, Fla.)》2019,31(3)
2D oxide nanomaterials constitute a broad range of materials, with a wide array of current and potential applications, particularly in the fields of energy storage and catalysis for sustainable energy production. Despite the many similarities in structure, composition, and synthetic methods and uses, the current literature on layered oxides is diverse and disconnected. A number of reviews can be found in the literature, but they are mostly focused on one of the particular subclasses of 2D oxides. This review attempts to bridge the knowledge gap between individual layered oxide types by summarizing recent developments in all important 2D oxide systems including supported ultrathin oxide films, layered clays and double hydroxides, layered perovskites, and novel 2D‐zeolite‐based materials. Particular attention is paid to the underlying similarities and differences between the various materials, and the subsequent challenges faced by each research community. The potential of layered oxides toward future applications is critically evaluated, especially in the areas of electrocatalysis and photocatalysis, biomass conversion, and fine chemical synthesis. Attention is also paid to corresponding novel 3D materials that can be obtained via sophisticated engineering of 2D oxides. 相似文献