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11.
Sample preparation for DNA and RNA assays is a prime candidate for laboratory automation. A novel, parallel processing device that performs the three separate liquid-handling functions necessary for such sample preparation-dispensing, pipetting, and pressurizing-is presented. The device comprises an array of fine nozzles connected by fluidic channels to automatically and precisely distribute flow between one source and an array of points. The design principles, as well as the experimental and computational methods used to develop the device, are described. Test results, including accuracy, uniformity, volume range, and timing, are presented. The functionality of the device is demonstrated by performing a solid-phase extraction of DNA with two types of microcolumns. 相似文献
12.
Packagings for the transport of dangerous goods are tested by four tests:- free fall, leakproofness, hydraulic pressure and stacking. However, the test procedures can be interpreted in different ways, particularly the stacking test. Some test authorities apply a guided load to the top of the package and others, including the LNE in France, use non-guided loads. The objective of recent research carried out at LNE was to evaluate the risk (in terms of stack stability for dangerous goods packagings) if the stacking tests are performed with guided loads rather than non-guided loads. The stacking tests were carried out on a limited number of plastic drums (200 of four types) submitted for qualification testing using the above four tests, with either guided or non-guided loads. From the results we conclude that:
- i for the transport of dangerous goods of Danger Group I, the field of use is not altered when tested by either procedure.
- ii with goods of Danger Groups II and III, the use of either procedure does not alter the position as far as transport is concerned. However, there is a risk in warehousing: the non-guided procedure being preferred.
13.
In aluminium plants, the anode baking process is associated with an important release of volatile combustible matter. It is the purpose of this study to investigate the kinetics of the evolution of these volatiles. A large thermogravimetry set-up has been designed in such a way that it could simulate real plant conditions. Samples of two distinct masses have been subjected to pyrolysis at different heating regimes. The loss of weight together with the concentrations of the released gases were recorded on a continuous basis during the temperature rise. Kinetic results were found for methane, hydrogen and tar. No variation of the order of reaction with the heating rate was observed, whereas the activation energy and the pre-exponential factor increased. Furthermore, for the range of sample dimensions studied, it was found that the mass of the solid had no significant influence on the kinetic parameters. 相似文献
14.
The diffusion of a plasticizer S1 from a source made of PVC containing 25 wt% of S1 into a medium made of PVC film containing another plasticizer S2 in 15, 20, 25 and 30 wt%, was studied at temperatures ranging from 70 to 108°C. S1 was generally diphenyl-iso-octyl phosphate (DPIP) and S2 was dioctyl phthalate (DOP) but the reciprocal system was also studied in some cases. Starting from a reference point corresponding to a temperature of 70°C and a DOP concentration of 25 wt%, it was found experimentally that an increase Δv of the DOP volume fraction (v) or an increase ΔT of the temperature, led to the same variation of the diffusion coefficient of DPIP if ΔT/Δv ~ 139K. A reasonably close value can be obtained from a simple free-volume approach, using the literature data on the plasticizer action of DOP on PVC. 相似文献
15.
Andre SULPICE Jean-Louis SOUBEYROUX Christophe VERWAERDE Gia Ky HOANG 《中国科学E辑(英文版)》2009,52(10):3071-3075
Two sets of internal-Sn Nb3Sn superconducting strands were fabricated through RRP method, one with 2 wt% of Ti alloyed in Sn core and the other just pure Sn. Four reaction temperatures of 650℃, 675℃, 700℃ and 725℃ and 128 h duration were applied for A15 phase formation heat treatment after Cu-Sn alloying procedure of 210℃/50 h + 340℃/25 h. For the heat-treated coil samples, transport non-Cu JC was examined through standard 4-probe technique and phase microstructure was observed by means of Field Emission Sc... 相似文献
16.
Marasca Andre Backes Andre Favarim Fabio Teixeira Marcelo Casanova Dalcimar 《国际自动化与计算杂志》2021,18(3):468-479
Machine Intelligence Research - The success of new scientific areas can be assessed by their potential for contributing to new theoretical approaches aligned with real-world applications. The... 相似文献
17.
We have studied the crystal structure of the uncommon phase with k=0 in ZrV2Dx, 2.2<x<2.5, which is an intermediate between the hydrogen-disordered phase and two hydrogen superstructures, ZrV2D<2 with k=(1/2 1/2 1/2) and ZrV2D>2.7 with k=(001). This phase is a primary superstructure combining the features of the disordered phase and, depending on the hydrogen concentration, one or another superstructure with k≠0. Its lattice (translational symmetry) is the same as in the disordered phase, which is k=0. Simultaneously, the lattice sites (the hydrogen arrangement in them) are prototypes of the sites of the subsequent superstructure with k≠0. Specifically, each site of the primary superstructure with k=0 is a mix of the sites with different spatial orientation of the superstructure with k≠0. In this sense the primary superstructure can be considered as a ‘lattice liquid crystal’ whereas usual superstructure with k≠0 is a ‘lattice crystal’. In addition, we have determined the crystal structure of the ‘ordered’ phase with k=(001) in ZrV2D2.73. It is a transitional state between the primary superstructure and the regular superstructure with the same k. 相似文献
18.
Mount Emily Gaultney Daniel Vrijsen Geert Adams Michael Baek So-Young Hudek Kai Isabella Louis Crain Stephen van Rynbach Andre Maunz Peter Kim Jungsang 《Quantum Information Processing》2016,15(12):5281-5298
Quantum Information Processing - Many of the challenges of scaling quantum computer hardware lie at the interface between the qubits and the classical control signals used to manipulate them.... 相似文献
19.
Andre Suslik Spritzer Jeremy Boy Pierre Dragicevic Jean‐Daniel Fekete Carla Maria Dal Sasso Freitas 《Computer Graphics Forum》2015,34(3):461-470
Node‐link infographics are visually very rich and can communicate messages effectively, but can be very difficult to create, often involving a painstaking and artisanal process. In this paper we present an investigation of node‐link visualizations for communication and how to better support their creation. We begin by breaking down these images into their basic elements and analyzing how they are created. We then present a set of techniques aimed at improving the creation workflow by bringing more flexibility and power to users, letting them manipulate all aspects of a node‐link diagram (layout, visual attributes, etc.) while taking into account the context in which it will appear. These techniques were implemented in a proof‐of‐concept prototype called GraphCoiffure, which was designed as an intermediary step between graph drawing/editing software and image authoring applications. We describe how GraphCoiffure improves the workflow and illustrate its benefits through practical examples. 相似文献
20.
Mohammad Amin Aliari Andre Beauchamp Tiberiu Popa Eric Paquette 《Computer Graphics Forum》2023,42(2):269-279
We propose an approach for interactive 3D face editing based on deep generative models. Most of the current face modeling methods rely on linear methods and cannot express complex and non-linear deformations. In contrast to 3D morphable face models based on Principal Component Analysis (PCA), we introduce a novel architecture based on variational autoencoders. Our architecture has multiple encoders (one for each part of the face, such as the nose and mouth) which feed a single decoder. As a result, each sub-vector of the latent vector represents one part. We train our model with a novel loss function that further disentangles the space based on different parts of the face. The output of the network is a whole 3D face. Hence, unlike part-based PCA methods, our model learns to merge the parts intrinsically and does not require an additional merging process. To achieve interactive face modeling, we optimize for the latent variables given vertex positional constraints provided by a user. To avoid unwanted global changes elsewhere on the face, we only optimize the subset of the latent vector that corresponds to the part of the face being modified. Our editing optimization converges in less than a second. Our results show that the proposed approach supports a broader range of editing constraints and generates more realistic 3D faces. 相似文献