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排序方式: 共有229条查询结果,搜索用时 15 毫秒
91.
Ronen A Gershon P Drobiner H Rabinovich A Bar-Hamburger R Mechoulam R Cassuto Y Shinar D 《Accident; analysis and prevention》2008,40(3):926-934
BACKGROUND: The effects of marijuana or THC on driving has been tested in several studies, but usually not in conjunction with physiological and subjective responses and not in comparison to alcohol effects on all three types of measures. OBJECTIVE: To assess the effects of two dosages of THC relative to alcohol on driving performance, physiological strain, and subjective feelings. METHOD: We tested the subjective feelings and driving abilities after placebo, smoking two dosages of THC (13 mg and 17 mg), drinking (0.05% BAC) and 24 h after smoking the high dose THC cigarette, while monitoring physiological activity of the drugs by heart rate. Fourteen healthy students, all recreational marijuana users, participated in the study. RESULTS: Both levels of THC cigarettes significantly affected the subjects in a dose-dependent manner. The moderate dose of alcohol and the low THC dose were equally detrimental to some of the driving abilities, with some differences between the two drugs. THC primarily caused elevation in physical effort and physical discomfort during the drive while alcohol tended to affect sleepiness level. After THC administration, subjects drove significantly slower than in the control condition, while after alcohol ingestion, subjects drove significantly faster than in the control condition. No THC effects were observed after 24 h on any of the measures. 相似文献
92.
Zhaoyang LIU Yangzhong ZHANG Swadesh Mitter MAH AJAN Adi LIU Tao XIE Chu ZHOU Tao LAN Jinlin XIE Hong LI Ge ZHUANG Wandong LIU 《等离子体科学和技术》2021,23(3):35101-50
Through a systematically developed theory, we demonstrate that the motion of Instanton identified in Zhang et al(2017 Phys. Plasmas 24 122304) is highly correlated to the intermittent excitation and propagation of geodesic acoustic mode(GAM) that is observed in tokamaks.While many numerical simulations have observed the phenomena, it is the first theory that reveals the physical mechanism behind GAM intermittent excitation and propagation. The preceding work is based on the micro-turbulence associated with toroidal ion temperature gradient mode, and slab-based phenomenological model of zonal flow. When full toroidal effect is introduced into the system, two branches of zonal flow emerge: the torus-modified low frequency zonal flow(TLFZF), and GAM, necessitating a unified exploration of GAM and TLFZF. Indeed, we observe that the transition from the Caviton to Instanton is triggered by a rapid zero-crossing of radial group velocity of drift wave and is found to be strongly correlated with the GAM onset. Many features peculiar to intermittent GAMs, observed in real machines,are thus identified in the numerical experiment. The results will be displayed in figures and in a movie; first for single central rational surface, and then with coupled multiple central rational surfaces. The periodic bursting first shown disappears as being replaced by irregular one, more similar to the intermittent characteristics observed in GAM experiments. 相似文献
93.
Adi Adumitroaie 《先进材料力学与结构力学》2015,22(9):705-716
Prediction of transverse damage initiation and evolution for not necessarily symmetric laminates under membrane and/or bending loads is the subject of this work. The laminate stiffness reduction is computed via crack opening displacement (COD) methods and the generalization to multiple cracking laminas is made via continuum damage mechanics (CDM) concepts. Using available COD solutions combined with homogenization techniques leads to an analytical constitutive model capable of predicting the initiation and evolution of crack density versus applied strain, as well as laminate modulus degradation, not only for symmetric laminates subjected to membrane deformation but also for general laminates subjected to flexural deformations as well. To adjust the model parameters, experimental data is required in the form of crack density, or modulus reduction, versus strain for two laminates of the same material system. Then, the model is capable of predicting crack density and modulus degradation for other laminate stacking sequences. The model takes into account crack closure, which is important under flexure, as well as the case of the center lamina straddling the neutral axis. The effect of thermal stresses is incorporated in the formulation. 相似文献
94.
95.
Beni Adi Trisna Ardi Rahman Asep Ridwan Nugraha Nur Tjahyo Eka Darmayanti Jimmy Pusaka 《Mapan》2018,33(4):469-480
As one of the emerging technologies in Indonesia, nanotechnology requires comprehensive studies of supporting infrastructures as well as the regulation that will underpin the quality of nanoproducts or nanoservices. Nanometrology is one of the most important supporting infrastructures for development of nanotechnology. This article reviews the importance of nanometrology and its standardization within the context of nanotechnology development in Indonesia. Current situation of nanotechnology development, relevant standards availability, necessity for new standards, nanometrology development and future goals have been explained. This article contributes novel insights about nanotechnology and nanometrology developments and may help the regulation body to make the policy. 相似文献
96.
Adi Kusmayadi Yoong Kit Leong Hong-Wei Yen Chi-Yu Huang Cheng-Di Dong Jo-Shu Chang 《国际能源研究杂志》2020,44(12):9254-9265
The world today is facing a crisis of energy and environmental pollution. Conventional or photosynthetic microbial fuel cell (MFC) is an advanced “green” energy technology that utilizes living microorganisms to convert biochemical or light energy into electricity through metabolic reaction and photosynthesis, offering a potential solution for the above-mentioned crisis. Further incorporating microalgae into MFC, microalgae-microbial fuel cell (mMFC) integrates electricity generation, wastewater treatment, CO2 sequestration and biomass production in a single, self-sustainable technology. This review first describes the fundamentals of MFC as well as its applications in treating domestic, municipal, agricultural and industrial wastewaters. Then, mMFC-based configurations and applications with its advantages compared with MFC are explained in particular, together with the parameters governing its performance. Lastly, the opportunities and challenges involved in the development of mMFCs are also explored. 相似文献
97.
Abstract. A data analysis estimation method called structural persistence is presented in this paper. Prediction applications of the method to time series with trend and seasonal components are discussed. The basic underlying assumption is that the structure of a given series does not change in the forecasting range. Therefore, when forecasts are made, the values which measure the structure (e.g. the trend shape) of the original and of the forecast-extended time series should be the same. We propose relaxed 'model-free' use of the principle which nevertheless provides an explicit prediction formula for the one-stepahead prediction P n +1 . Missing data can also be estimated using this method. The procedure is applied to some previously published time series data and the prediction results are compared with those obtained using the Box-Jenkins approach. 相似文献
98.
Jingwen Sun Ravit Malishev Adi Azoulay Jonathan Tzadikov Michael Volokh Raz Jelinek Menny Shalom 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(21)
2D carbon and nitrogen based semiconductors (CN) have attracted widespread attention for their possible use as low‐cost and environmentally friendly materials for various applications. However, their limited solution‐dispersibility and the difficulty in preparing exfoliated sheets with tunable photophysical properties restrain their exploitation in imaging‐related applications. Here, the synthesis of carbon and nitrogen organic scaffolds with highly tunable optical properties, excellent dispersion in water and DMSO, and good bioimaging properties is reported. Tailored photophysical and chemical properties are acquired by the synthesis of new starting monomers containing different substituent chemical groups with varying electronic properties. Upon monomer condensation at moderate temperature, 350 °C, the starting chemical groups are fully preserved in the final CN. The low condensation temperature and the effective molecular‐level modification of the CN scaffold lead to well‐dispersed photoluminescent CN thin sheets with a wide range of emission wavelengths. The good bioimaging properties and the tunable fluorescence properties are exemplified by in situ visualization of giant unilamellar vesicles in a buffered aqueous solution as a model system. This approach opens the possibility for the design of tailor‐made CN materials with tunable photophysical and chemical properties toward their exploitation in various fields, such as photocatalysis, bioimaging, and sensing. 相似文献
99.
100.
Adi Shamir 《计算机教育》2009,(16):25-32
<正>It's all us pleasure to come to China, a great deal of cheerful times already. I hope that we have additional opportunity to meet, talk about cryptography and other components. Today I am going to give a general talk which is not designed for special lists, about how could the systems get 相似文献