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81.
Essential Amino Acid Composition of Fleshy Fruits Versus Maintenance Requirements of Passerine Birds
Ido Izhaki 《Journal of chemical ecology》1998,24(8):1333-1345
Nutritional analyses were performed on 27 fruit species that are eaten by frugivorous birds in east Mediterranean habitats in Israel. The essential amino acid (EAA) profile [compared by principal component analysis (PCA)] of these fruits indicated two distinct groups of fruits. The main group consisted of 23 species that were similar in their relatively low total EAA quantities and unbalanced EAA profiles. On average, the EAAs phenylalanine and tyrosine were most concentrated and histidine least (tryptophan was not measured). Comparing the relative amounts of EAAs in fruits with required amounts for maintenance of granivorous passerine birds revealed that these fruits are deficient in all or most EAAs. The sulfur-containing amino acids (methionine and cystine) were most limiting relative to the required amount (41–61% below requirement), while four others (arginine, lysine, isoleucine, and leucine) were severely deficient (30–37% below requirement). These results complement reports suggesting that frugivorous birds have lower total protein demands than granivores. The second group of four fruit species had relatively high total EAA contents. Each of these fruits appeared to contain especially large quantities of some EAAs, but it was uncertain whether some high concentrations could have resulted from interactions in the pulp during preparation and chemical analysis. 相似文献
82.
Seiji Katayama Ryouji Ido Koji Nishimoto Masami Mizutani Yousuke Mizutani 《Welding International》2018,32(5):289-302
This study was undertaken in order to investigate the effect of reduced ambient pressure from an atmospheric pressure (101 kPa) to 0.1 kPa on one-pass full penetration welding of thick high-tensile strength steel plate of 23 mm thickness. A 16 kW disk laser of 1030 nm in wavelength was employed to weld HT980 grade plates at the speed of 5–25 mm/s. In partial penetration welding, it was revealed that humping phenomena occurred easily. Full penetration welding of the high-tensile strength steel plates could not be achieved at 101 kPa. On the other hand, full penetration welding was obtained at the welding speed of less than 20 mm/s at the pressure of less than 10 kPa. Especially, at 0.1 kPa, and 17 and 20 mm/s, sound weld joints without defects were obtained. According to the observation results of a keyhole inlet and a surface molten pool during welding with a high-speed video camera, the melt in front of a keyhole was smaller and the behaviour of a keyhole and a plume was much more stable at 0.1 kPa than at 101 kPa. Moreover, in the full penetration welding, spattering was suppressed under the proper conditions. Such phenomena became more stable in fast welding. It was revealed in laser welding of thick high-tensile strength steel plates that the formation of narrow I-shaped weld beads by achieving full-penetration welding in low vacuum was essential for the production of sound welds without defect. 相似文献
83.
Columbus I Waysbort D Shmueli L Nir I Kaplan D 《Environmental science & technology》2006,40(12):3952-3958
The fate of the persistent OP nerve agent O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX) on granular activated carbons that are used for gas filtration was studied by means of 31P magic angle spinning (MAS) NMR spectroscopy. VX as vapor or liquid was adsorbed on carbon granules, and MAS NMR spectra were recorded periodically. The results show that at least 90% of the adsorbed VX decomposes within 20 days or less to the nontoxic ethyl methylphosphonic acid (EMPA) and bis(S-2-diisopropylaminoethane) {(DES)2}. Decomposition occurred irrespective of the phase from which VX was loaded, the presence of metal impregnation on the carbon surface, and the water content of the carbon. Theoretical and practical aspects of the degradation are discussed. 相似文献
84.
Matt Zarek Michael Layani Shira Eliazar Nicola Mansour Ido Cooperstein Efrat Shukrun 《Virtual and Physical Prototyping》2016,11(4):263-270
4D printing is a novel approach that enables dynamic functionality in ordinary static object. We used a methacrylated semicrystalline polymer to print objects exhibiting thermally triggered shape memory behaviour. By exploring various molecular weights, it was found that a methacrylated polycaprolactone polymer with a number average molecular weight of 10,000?g?mol?1 exhibited the best thermal and mechanical behaviour. The effect of dyes’ addition to the ink formulation on the photopolymerisation and on the printing processes was evaluated. The ink was utilised for demonstrating fabrication of dynamic jewellery and a shoe accessory by Digital Light Processing printing. 相似文献
85.
N. Momono T. Matsuzaki T. Nagata M. Oda M. Ido 《Journal of Low Temperature Physics》1999,117(3-4):353-357
In La214, the electronic specific heat coefficient (=C
el
/T) is gradually suppressed with lowering T below a certain temperature T* (> T
c
), where the in-plane resistivity and magnetic susceptibility also tend to be suppressed slightly. Temperature T*, increasing with lowering x, is in qualitative agreement with the mean field T
c
(T
co
), estimated from the superconducting gap amplitude 2
o
at T T
c
, as the onset temperature T* of a pseudogap in Bi2212. The gradual suppression of below T
co
implies that a pseudogap will also open up below T
co
in La214 as in Bi2212. In underdoped samples, whose pseudogap-like behaviors in C
el(T) become marked, the anomaly of C
el
around T
c
is rather different from the BCS expectation. 相似文献
86.
Younhyun Jung Jinman Kim Stefan Eberl Micheal Fulham David Dagan Feng 《The Visual computer》2013,29(6-8):805-815
Multi-modality (MM) positron emission tomography-computed tomography (PET-CT) visualises biological and physiological functions (from PET) as region of interests (ROIs) within a higher resolution anatomical reference frame (from CT). The need to efficiently assess and assimilate the information from these co-aligned volumes simultaneously has stimulated new visualisation techniques that combine 3D volume rendering with interactive transfer functions to enable efficient manipulation of these volumes. However, in typical MM volume rendering visualisation, the transfer functions for the volumes are manipulated in isolation with the resulting volumes being fused, thus failing to exploit the spatial correlation that exists between the aligned volumes. Such lack of feedback makes MM transfer function manipulation complex and time consuming. Further, transfer function alone is often insufficient to select the ROIs when they have similar voxel properties to those of non-relevant regions. In this study, we propose a new ROI-based MM visibility-driven transfer function (m 2-vtf) for PET-CT visualisation. We present a novel ‘visibility’ metric, a fundamental optical property that represents how much of the ROIs are visible to the users, and use it to measure the visibility of the ROIs in PET in relation to how it is affected by transfer function manipulations to its counterpart CT. To overcome the difficulty in ROI selection, we provide an intuitive ROI selection tool based on automated PET segmentation. We further present a MM transfer function automation where the visibility metrics from the PET ROIs are used to automate its CT’s transfer function. Our GPU implementation achieved an interactive visualisation of PET-CT with efficient and intuitive transfer function manipulations. 相似文献
87.
Morag I 《Applied ergonomics》2007,38(2):201-211
The occupational ergonomic program that Intel's newly established manufacturing plant in Israel implemented in 1997 helped prevent injuries and also marked the launch of a whole new approach to ergonomics. A key element in the success of the seven-point program was a strong commitment from management, which came to regard this plan as a vital strategic element in the new plant's success. Comprehensive, top-down planning imposed obligations on all elements in the manufacturing spectrum, from suppliers to contractors to employees. Work requirements were set; cooperation with the plant's occupational health professionals was established; and long-term reporting and instruction systems were developed. Extensive ergonomic training was a crucial factor in integrating ergonomic procedures into the organization's day-to-day activities. Along with this instructional program, ergonomic engineers implemented a strict measuring system to ensure that each ergonomic activity would be performed according to schedule. By the time the factory opened its gates and began to produce, a vigorous ergonomic environment had emerged and employees were displaying an ergonomic mindset that also impinged upon their non-work activities. As a result of the successful implementation of the program, Intel's ergonomic program has become a model for Israeli industry. This paper presents a full ergonomic program that besides supplying the Intel plant with solutions was unique enough to impact the whole Israeli industry. 相似文献
88.
89.
Wen L Eberl S Choi HC Feng DD Fulham M 《Computer methods and programs in biomedicine》2008,89(2):102-111
Functional imaging with PET and SPECT is capable of visualizing subtle changes in physiological function in vivo, which aids in the early diagnosis of disease. Quantitative functional parameters are usually derived by curve fitting the dynamic data of a functional imaging study. However, the intrinsic high level of noise and low signal to noise ratio can lead to instability in the parameter estimation and give rise to non-physiological parameter estimates. Clustering techniques have been applied to improve signal to noise ratio and the reliability of parametric image generation, but these may enhance partial volume effects (PVE) and result in biased estimates for small structures. Therefore, a systematic study was performed using computer simulations of SPECT data and the generalized linear least square algorithm (GLLS) to evaluate the ability of three proposed enhanced methods and a clustering-aided method to improve the reliability of parametric image generation. The results demonstrate that clustering with sufficient cluster numbers ameliorated PVE and provided noise-insensitive parameter estimates. The enhanced GLLS method with a prior volume of distribution and bootstrap Monte Carlo resampling improved the reliability of the curve fitting, and is thus suitable for application to noisy SPECT data. 相似文献
90.
An intervention study was conducted to examine the effectiveness of an innovative self-modeling photo-training method for reducing musculoskeletal risk among office workers using computers. Sixty workers were randomly assigned to either: 1) a control group; 2) an office training group that received personal, ergonomic training and workstation adjustments or 3) a photo-training group that received both office training and an automatic frequent-feedback system that displayed on the computer screen a photo of the worker's current sitting posture together with the correct posture photo taken earlier during office training. Musculoskeletal risk was evaluated using the Rapid Upper Limb Assessment (RULA) method before, during and after the six weeks intervention. Both training methods provided effective short-term posture improvement; however, sustained improvement was only attained with the photo-training method. Both interventions had a greater effect on older workers and on workers suffering more musculoskeletal pain. The photo-training method had a greater positive effect on women than on men. 相似文献