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131.
Federico Bolognesi Nicola Fazio Filippo Boriani Viscardo Paolo Fabbri Davide Gravina Francesca Alice Pedrini Nicoletta Zini Michelina Greco Michela Paolucci Maria Carla Re Sofia Asioli Maria Pia Foschini Antonietta DErrico Nicola Baldini Claudio Marchetti 《International journal of molecular sciences》2022,23(3)
Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze–thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique. 相似文献
132.
Camilla Costa Renzo Di Felice Paolo Moretti Maddalena Oliva Rouzbeh Ramezani 《加拿大化工杂志》2020,98(12):2516-2529
This work is a companion to a previous article, Part I, published in The Canadian Journal of Chemical Engineering, dealing with CO2 absorption in aqueous solutions containing a single aminic reagent (specifically methyldiethanolamine (MDEA) or piperazine (PZ)). In this second part, different PZ/MDEA mixtures are experimentally studied and their performances are compared with that of the single reagents. It is indeed well known that small quantities of PZ added to MDEA aqueous solutions are sufficient to obtain a significant improvement in the kinetics of the process. PZ is considered an activator or promoter for MDEA, but the mechanism of this synergy has still not been clearly demonstrated. The aim of this study is an attempt to understand how PZ and MDEA can interact by experimentally analyzing this beneficial mutual effect and by explaining it with the help of a suitable yet not complex model. We believe that the involved chemistry is not more complex than that reported in Part I for the single reagents. According to our findings, it is MDEA that enhances the action of PZ, as opposed to what many authors claim. Moreover, our results seem to rule out the existence of any PZ shuttle effect. 相似文献
133.
In this paper, data are reported for the behaviour of some charcoals during combustion and devolatilization in a thermal analyser. 相似文献
134.
Francesco P. La Mantia Roberto Scaffaro Graziana Carianni Paolo Mariani 《大分子材料与工程》2005,290(3):159-164
Summary: The rheological behavior of polyethylenes is mainly dominated by the molecular weight, the molecular weight distribution and by the type, the amount and the distribution of the chain branches. In this work a linear metallocene catalyzed polyethylene (m‐PE), a branched metallocene catalyzed polyethylene (m‐bPE), a conventional linear low density polyethylene (LLDPE) and a low density polyethylene (LDPE) have been investigated in order to compare their rheological behavior in shear and in elongational flow. The four samples have similar melt flow index and in particular a value typical of film blowing grade. The melt viscosity has been studied both in shear and in isothermal and non‐isothermal elongational flow. The most important features of the results are that in shear flow the m‐PE sample shows less pronounced non Newtonian behavior while in the elongational flow the behavior of m‐PE is very similar to that of the linear low density polyethylene: the narrower molecular weight distribution and the better homogeneity of the branching distribution are reasonably responsible for this behavior. Of course the most pronounced non‐linear behavior is shown, as expected, by the LDPE sample and by the branched metallocene sample. This similar behavior has to be attributed to the presence of branching. Similar comments hold in non‐isothermal elongational flow; the LDPE sample shows the highest values of the melt strength and the other two samples show very similar values. As for the breaking stretching ratio the opposite is true for LDPE while m‐PE and LLDPE show higher values. The transient isothermal elongational viscosity curves show that the branched samples show a strain hardening effect, while LLDPE and m‐PE samples present a linear behavior.
135.
Subcritical hydrolysis and characterization of waste proteinaceous biomass for value added applications 总被引:1,自引:0,他引:1 下载免费PDF全文
136.
Corrigendum: Discovery of a Potent BTK Inhibitor with a Novel Binding Mode by Using Parallel Selections with a DNAEncoded Chemical Library 下载免费PDF全文
137.
Nejib Kasmi Martina Roso Nadia Hammami Mustapha Majdoub Carlo Boaretti Paolo Sgarbossa 《Designed Monomers and Polymers》2017,20(1):547-563
In order to prepare thermally stable isosorbide-derived thermoplastic polyurethane, the synthesis of two new chiral exo–exo configured diols, prepared from isosorbide, and two types of diphenols (bisphenol A and thiodiphenol) was described. The synthesis conditions were optimized under conventional heating and microwave irradiations. To prove their suitability in polymerization, these monomers were successfully polymerized using 4,4′-diphenylmethane diisocyanate (MDI) and hexamethylene diisocyanate (HDI). Both monomers and polymers have been studied by NMR, FT-IR, TGA, DSC; intrinsic viscosity of polymers has also been determined. The results showed the effectiveness of the synthetic strategy proposed; moreover, a dramatic reduction of the reaction time and an important improvement of the monomers yield using microwave irradiation have been demonstrated. The monomers, as well as the polymers, showed excellent thermal stability both in air and nitrogen. It was also shown that the introduction of sulphur in the polyurethane backbone was effective in delaying the onset of degradation as well as the degradation rate. 相似文献
138.
Corrado Costa Paolo Menesatti Jacopo Aguzzi Stefano D’Andrea Francesca Antonucci Valentina Rimatori Federico Pallottino Marco Mattoccia 《Food and Bioprocess Technology》2010,3(1):43-48
The actual Italian production of clams is chiefly sustained by the native Tapes decussatus and the fortuitously imported Tapes philippinarum. Both species are commercialized as “Vongola verace”, but the commercial value of T. philippinarum is lower. The discrimination of species by sight is usually difficult and it cannot be done by observation based on shell
morphology but only when animals open their valves hence displaying the two siphons. In this study, we propose a new, noninvasive
method to discriminate individuals of both species based on the analysis of the external shape of their shells. Accordingly,
in sympatric populations at two sites of the Po river outlet, we have chosen individuals (63 for T. decussatus and 57 for T. philippinarum) of comparable commercial size for which a certain genetic discrimination was previously done. Pictures of the left side
valve were taken for all specimens. Their profiles were analyzed with the elliptic Fourier analysis. The mean outline for
each species was graphically extracted. The coefficients of the harmonic equations were analyzed by multivariate classification
(partial least squares discriminant analysis [PLSDA]). Results showed a high percentage of correct classification of individuals
of both species (96.6%). Contour analysis reflected the overall shell shape and thus identified morphological aspects that
were difficult to recognize and quantify in sight. The high percentage of correct classifications obtained by combining the
analysis of elliptic Fourier harmonics with PLSDA demonstrated the feasibility of this method to discriminate species with
a high level of resemblance. 相似文献
139.
Analysis of Optical Losses in a Photoelectrochemical Cell: A Tool for Precise Absorptance Estimation 下载免费PDF全文
Peter Cendula Ludmilla Steier Paolo A. Losio Michael Grätzel Jürgen O. Schumacher 《Advanced functional materials》2018,28(1)
Optical losses in a photoelectrochemical (PEC) cell account for a substantial part of solar‐to‐hydrogen conversion losses, but limited attention is paid to the detailed investigation of optical losses in PEC cells. In this work, an optical model of combined coherent and incoherent light propagation in all layers of the PEC cell based on spectroscopic measurements is presented. Specifically, photoelectrodes using transparent conductive substrates such as F:SnO2 coated with thin absorber films are focused. The optical model is verified for hematite photoanodes fabricated by atomic layer deposition and successfully used to determine wavelength‐dependent reflection, transmission, layer absorptances, and charge generation rates. Furthermore, the calculated absorptances enable 20–30% more accurate calculations of the absorbed photon‐to‐current efficiency of PEC cells. Our optical model is a powerful tool for the optimization of the optical performance of PEC cells focusing on single absorber or tandem configurations and represents a cornerstone of a complete (optical and electrical) model for PEC water splitting cells. 相似文献
140.
Electroactive Ionic Soft Actuators with Monolithically Integrated Gold Nanocomposite Electrodes 下载免费PDF全文
Yunsong Yan Tommaso Santaniello Luca Giacomo Bettini Chloé Minnai Andrea Bellacicca Riccardo Porotti Ilaria Denti Gabriele Faraone Marco Merlini Cristina Lenardi Paolo Milani 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
Electroactive ionic gel/metal nanocomposites are produced by implanting supersonically accelerated neutral gold nanoparticles into a novel chemically crosslinked ion conductive soft polymer. The ionic gel consists of chemically crosslinked poly(acrylic acid) and polyacrylonitrile networks, blended with halloysite nanoclays and imidazolium‐based ionic liquid. The material exhibits mechanical properties similar to that of elastomers (Young's modulus ≈ 0.35 MPa) together with high ionic conductivity. The fabrication of thin (≈100 nm thick) nanostructured compliant electrodes by means of supersonic cluster beam implantation (SCBI) does not significantly alter the mechanical properties of the soft polymer and provides controlled electrical properties and large surface area for ions storage. SCBI is cost effective and suitable for the scaleup manufacturing of electroactive soft actuators. This study reports the high‐strain electromechanical actuation performance of the novel ionic gel/metal nanocomposites in a low‐voltage regime (from 0.1 to 5 V), with long‐term stability up to 76 000 cycles with no electrode delamination or deterioration. The observed behavior is due to both the intrinsic features of the ionic gel (elasticity and ionic transport capability) and the electrical and morphological features of the electrodes, providing low specific resistance (<100 Ω cm?2), high electrochemical capacitance (≈mF g?1), and minimal mechanical stress at the polymer/metal composite interface upon deformation. 相似文献