全文获取类型
收费全文 | 580篇 |
免费 | 12篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 168篇 |
金属工艺 | 3篇 |
机械仪表 | 9篇 |
建筑科学 | 36篇 |
矿业工程 | 1篇 |
能源动力 | 13篇 |
轻工业 | 54篇 |
水利工程 | 7篇 |
石油天然气 | 3篇 |
无线电 | 60篇 |
一般工业技术 | 107篇 |
冶金工业 | 26篇 |
原子能技术 | 2篇 |
自动化技术 | 99篇 |
出版年
2024年 | 13篇 |
2023年 | 5篇 |
2022年 | 10篇 |
2021年 | 14篇 |
2020年 | 16篇 |
2019年 | 13篇 |
2018年 | 13篇 |
2017年 | 19篇 |
2016年 | 17篇 |
2015年 | 6篇 |
2014年 | 20篇 |
2013年 | 30篇 |
2012年 | 31篇 |
2011年 | 27篇 |
2010年 | 23篇 |
2009年 | 14篇 |
2008年 | 28篇 |
2007年 | 28篇 |
2006年 | 22篇 |
2005年 | 27篇 |
2004年 | 21篇 |
2003年 | 15篇 |
2002年 | 15篇 |
2001年 | 10篇 |
2000年 | 12篇 |
1999年 | 7篇 |
1998年 | 11篇 |
1997年 | 4篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 5篇 |
1993年 | 10篇 |
1992年 | 5篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 7篇 |
1986年 | 9篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1974年 | 4篇 |
1972年 | 3篇 |
1968年 | 7篇 |
1967年 | 2篇 |
排序方式: 共有593条查询结果,搜索用时 0 毫秒
51.
The T-stress term of DCDC specimens is computed using the Boundary Collocation procedure and limit case consideratons. This parameter allows to understand path stability as found in literature for subcritical crack growth in galss. 相似文献
52.
53.
Pavan TZ Almeida TW Carneiro AA 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(5):909-915
The dynamic behavior of a rigid magnetic sphere induced by an acoustic radiation force was investigated. The sphere was suspended in water in a simple pendulum configuration. The drag force acting on the pendulum during its motion was considered to follow a modified Stokes law for a low Reynolds number, accounting for phenomena related to its oscillatory movement. Steady forces of long (a few seconds) and short (a few milliseconds) durations were used. The movement of the magnetic sphere was tracked using a magnetoresistive sensor. From the new equilibrium position of the sphere in response to the long-duration static radiation force, the amplitude of this force was estimated. To assess the water viscosity, the relaxation movement after the acoustic force had stopped was fitted to a harmonic-motion model. Based on the results for the acoustic force and water viscosity, a theoretical profile of the sphere's micro-order displacement as a function of time caused by short-duration acoustic radiation force agreed well with experimental results. 相似文献
55.
Om Prakash Singh Andrea Bocchino Theo Guillerm Yuan Hu Frank Stam Conor O'Mahony 《Advanced Materials Technologies》2024,9(3):2301606
Microneedle-based electrodes have attracted significant attention due to their potential applications in high-quality, long-term electrophysiological monitoring. In this study, micromoulding technology is used to develop a flexible, conductive fabric microneedle (CF–MN) electrode by bonding a conductive textile to polymeric microneedle arrays. The resulting electrode conforms to the curved surfaces of the body, and the use of a conductive textile backing reduces metallization time and costs by 50% over double-sided dry electrodes. The electrode-skin impedance of the CF–MN electrodes is significantly lower than that of gel electrodes over a wide frequency range, and tests on healthy volunteers, both at rest and under a range of ambulatory conditions, showed that the electrodes are capable of acquiring electrocardiography (ECG) and electromyography (EMG) signals that have a comparable kurtosis and signal-to-noise ratio to those recorded using conventional electrodes, but without the need for skin preparation or the use of a wet gel. The biomechanical properties of the electrode are also characterized. This is the first demonstration of CF–MN electrodes that can ultimately be integrated into clothing, which in turn can facilitate personalized cardiac health management by enabling continuous, long-term ECG/EMG monitoring during daily activities. 相似文献
56.
Elizaveta Semenova Yidan Xu Adam Howes Theo Rashid Samir Bhatt Swapnil Mishra Seth Flaxman 《Journal of the Royal Society Interface》2022,19(191)
Gaussian processes (GPs), implemented through multivariate Gaussian distributions for a finite collection of data, are the most popular approach in small-area spatial statistical modelling. In this context, they are used to encode correlation structures over space and can generalize well in interpolation tasks. Despite their flexibility, off-the-shelf GPs present serious computational challenges which limit their scalability and practical usefulness in applied settings. Here, we propose a novel, deep generative modelling approach to tackle this challenge, termed PriorVAE: for a particular spatial setting, we approximate a class of GP priors through prior sampling and subsequent fitting of a variational autoencoder (VAE). Given a trained VAE, the resultant decoder allows spatial inference to become incredibly efficient due to the low dimensional, independently distributed latent Gaussian space representation of the VAE. Once trained, inference using the VAE decoder replaces the GP within a Bayesian sampling framework. This approach provides tractable and easy-to-implement means of approximately encoding spatial priors and facilitates efficient statistical inference. We demonstrate the utility of our VAE two-stage approach on Bayesian, small-area estimation tasks. 相似文献
57.
Gilles Lenfant Marie‐Claude Heuzey Theo G. M. van de Ven Pierre J. Carreau 《加拿大化工杂志》2017,95(10):1891-1900
58.
A series all‐aromatic poly(esterimide)s with different molar ratios of N‐(3′‐hydroxyphenyl)‐trimellitimide (IM) and 4‐hydroxybenzoic acid (HBA) (IM/HBA = 0.3/0.7 and 0.7/0.3) was prepared with the aim to design flexible high Tg films. Melt‐pressed films, either from high molecular weight polymer or cured phenylethynyl precursor oligomers, exhibit Tgs in the range of 200 °C to 242 °C and are brittle. After a thermal stretching procedure, the films became remarkably flexible and very easy to handle. In addition, the thermally stretched 3‐IM/7‐HBA and 7‐IM/3‐HBA films show tensile strengths of 108 MPa and 169 MPa, respectively. Thermal treatment increased the Tg of 3‐IM/7‐HBA from 205 °C to 248 °C, whereas the Tg of 7‐IM/3‐HBA increased from 230 °C to 260 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 133, 44774. 相似文献
59.
Takeo Uchida Keita Abe Yuma Endo Shosei Ichiseki Satoru Akita Shiyun Liu Sho Aradachi Masataka Saito Akihiko Fukuchi Taiyo Kikkawa Theo Dammaretz Ibuki Kawamata Yuki Suzuki Shin‐ichiro M. Nomura Satoshi Murata 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(41)
A new kind of the Vernier mechanism that is able to control the size of linear assembly of DNA origami nanostructures is proposed. The mechanism is realized by mechanical design of DNA origami, which consists of a hollow cylinder and a rotatable shaft in it connected through the same scaffold. This nanostructure stacks with each other by the shape complementarity at its top and bottom surfaces of the cylinder, while the number of stacking is limited by twisting angle of the shaft. Experiments have shown that the size distribution of multimeric assembly of the origami depends on the twisting angle of the shaft; the average lengths of the multimer are decamer, hexamer, and tetramer for 0°, 10°, and 20° twist, respectively. In summary, it is possible to affect the number of polymerization by adjusting the precise shape and movability of a molecular structure. 相似文献
60.
Bob C. Schroeder Tadanori Kurosawa Tianren Fu Yu‐Cheng Chiu Jaewan Mun Ging‐Ji Nathan Wang Xiaodan Gu Leo Shaw James W. E. Kneller Theo Kreouzis Michael F. Toney Zhenan Bao 《Advanced functional materials》2017,27(34)
The solid‐state packing and polymer orientation relative to the substrate are key properties to control in order to achieve high charge carrier mobilities in organic field effect transistors (OFET). Intuitively, shorter side chains are expected to yield higher charge carrier mobilities because of a denser solid state packing motif and a higher ratio of charge transport moieties. However our findings suggest that the polymer chain orientation plays a crucial role in high‐performing diketopyrrolopyrrole‐based polymers. By synthesizing a series of DPP‐based polymers with different branched alkyl side chain lengths, it is shown that the polymer orientation depends on the branched alkyl chain lengths and that the highest carrier mobilities are obtained only if the polymer adopts a mixed face‐on/edge‐on orientation, which allows the formation of 3D carrier channels in an otherwise edge‐on‐oriented polymer chain network. Time‐of‐flight measurements performed on the various polymer films support this hypothesis by showing higher out‐of‐plane carrier mobilities for the partially face‐on‐oriented polymers. Additionally, a favorable morphology is mimicked by blending a face‐on polymer into an exclusively edge‐on oriented polymer, resulting in higher charge carrier mobilities and opening up a new avenue for the fabrication of high performing OFET devices. 相似文献