全文获取类型
收费全文 | 1436篇 |
免费 | 75篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 39篇 |
综合类 | 2篇 |
化学工业 | 444篇 |
金属工艺 | 10篇 |
机械仪表 | 31篇 |
建筑科学 | 46篇 |
能源动力 | 49篇 |
轻工业 | 160篇 |
水利工程 | 10篇 |
石油天然气 | 5篇 |
无线电 | 157篇 |
一般工业技术 | 224篇 |
冶金工业 | 92篇 |
原子能技术 | 8篇 |
自动化技术 | 236篇 |
出版年
2024年 | 5篇 |
2023年 | 27篇 |
2022年 | 67篇 |
2021年 | 96篇 |
2020年 | 48篇 |
2019年 | 49篇 |
2018年 | 51篇 |
2017年 | 38篇 |
2016年 | 54篇 |
2015年 | 36篇 |
2014年 | 85篇 |
2013年 | 88篇 |
2012年 | 94篇 |
2011年 | 110篇 |
2010年 | 84篇 |
2009年 | 61篇 |
2008年 | 53篇 |
2007年 | 60篇 |
2006年 | 64篇 |
2005年 | 35篇 |
2004年 | 32篇 |
2003年 | 31篇 |
2002年 | 23篇 |
2001年 | 21篇 |
2000年 | 12篇 |
1999年 | 15篇 |
1998年 | 26篇 |
1997年 | 30篇 |
1996年 | 19篇 |
1995年 | 14篇 |
1994年 | 7篇 |
1993年 | 13篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1985年 | 5篇 |
1984年 | 1篇 |
1983年 | 5篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 5篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有1513条查询结果,搜索用时 15 毫秒
1.
Miriam A Martinello Mauro Villegas Maria del C Pramparo 《Journal of the science of food and agriculture》2007,87(8):1559-1563
A process of physical refining wheat germ oil using the technique of molecular distillation (MD) is presented in this work. Wheat germ oil was obtained from the germ by solvent extraction using hexane and also by cold pressing. The oil extracted with hexane was degummed and bleached before deacidification in order to modify the parameters of phosphorus and color. The goal in carrying out the stage of physical refining by MD was to preserve the maximum amount of original antioxidative potential obtained from extraction of the crude oil. The effect of evaporation temperature of one‐stage MD on the efficiency of free fatty acid elimination was studied. The antioxidant portion was followed by means of analytic determination of tocopherols by high‐performance liquid chromatography. Tocopherol retention up to 98% was achieved in the oil extracted by pressing, and yields of up to 96% were achieved in the oil extracted with hexane. Copyright © 2007 Society of Chemical Industry 相似文献
2.
Massimiliano Corsini Elisa Drelie Gelasca Touradj Ebrahimi Mauro Barni 《Multimedia, IEEE Transactions on》2007,9(2):247-256
This paper addresses the problem of assessing distortions produced by watermarking 3D meshes. In particular, a new methodology for subjective evaluation of the quality of 3D objects is proposed and implemented. Two objective metrics derived from measures of surface roughness are then proposed and their efficiency to predict the perceptual impact of 3D watermarking is assessed and compared with the state of the art. Results obtained show good correlations between the proposed objective metrics and subjective assessments by human observers 相似文献
3.
Enzo Benedetti Aldo D'Alessio Mauro Aglietto Giacomo Ruggeri Piergiorgio Vergamini Francesco Ciardelli 《Polymer Engineering and Science》1986,26(1):9-14
Polyolefins functionalized with diethylmaleate were mixed with poly(vinylchloride) (PVC) in different compositions. Intermolecular interactions involving the carbonyl groups of the side chains of the functionalized polyolefins and methine hydrogens of PVC were investigated by means of infrared spectroscopy. The major flexibility of the ester groups attached to the backbone chains, with respect to polyesters, seems to increase the capability of such groups to interact with groups of more polar polymers, thus allowing prediction of easier miscibility, which however also depends on the starting polyolefin structure and function-alization degree. 相似文献
4.
L Magaudda MR Mondello DD Di Mauro S Pallio M Bottari 《Canadian Metallurgical Quarterly》1996,42(2):61-69
The effects of antiepileptic drugs on cognitive function in 48 healthy volunteers were assessed using event-related potentials (ERP) and the Attention Index included in the Wechsler Memory Scale, revised edition (WMS-R). The study was conducted over 1 week, using a double-blind design. Four drugs, carbamazepine (CBZ), phenytoin (PHT), valproate (VPA) and zonisamide (ZNS) were tested. Using an auditory oddball task, ERP measurements were made under two conditions with different tone intensities: Condition 1 used 70 db SPL; and Condition 2 used 30 db SPL. Results showed that CBZ prolonged target N1 and P3 latencies in Condition 1, and reduced frequent N1 amplitude in Condition 2, which suggests that CBZ may cause a change in sensory memory and prolong stimulus evaluation time. It is suggested that under a low stimulus intensity level, the sensory function itself was affected. Phenytoin was found to prolong target N1 latency in Condition 2, which also indicates a change in the sensory memory function. However, VPA did not significantly affect ERP components, except for the shortened frequent N1 latency, which could not be explained due to the limited information. It was found that ZNS augmented P3 amplitude in Condition 2, and reduced scores on the Attention Index. It is suggested that the augmentation of P3 amplitude was caused by the reduction of processing negativity as a result of the detrimental effect of ZNS on subjects' attention. However, the apparent difference between the ERP and behavioral indices suggests that caution should be exercised in assessing the results obtained only from ERP measurements. 相似文献
5.
The IBF has for some years made use of finite element programmes to solve metal-forming problems. In the course of this investigation, it has become evident that a problem-oriented adaptation of FEM simulation to the problem in hand is beneficial in terms of computation effort. The computation time for the process parameters is optimised in a multi-level simulation. At level 1 (global analysis) integral parameters such as the required force and required work are computed using a coarse FEM mesh. At level 2 (local analysis) an optimised number of elements is used to determine continuum mechanics parameters like stress, strain and temperature. Microscopic phenomena are simulated at level 3 (microscopic analysis), using special micro-material elements and thermodynamic models. 相似文献
6.
Mauro Sassu 《Canadian Metallurgical Quarterly》2003,129(6):607-612
A plane elastic-plastic solid body presenting kinematic hardening is used to simulate a pair of dampers at the base of a rigid structure and determine the energy dissipation under conditions of assigned, homogeneous cyclic loading. The well-known von Mises theory of plasticity is applied with the aim of obtaining analytical solutions to the problem. Such solutions are arrived at by first calculating the Odqvist parameter, which yields dimensionless relations that depend on the external loads and mechanical properties of the material. The results, in terms of dissipated energy, are given for the case of a sinusoidal process, represented with the help of dimensionless parameters useful for engineering applications. 相似文献
7.
RF Buckman MM Badellino LH Mauro JA Asensio C Caputo J Gass JD Grosh 《Canadian Metallurgical Quarterly》1993,34(5):717-25; discussion 725-7
A prospective study of 66 consecutive patients with cardiac wounds seen over a 27-month period is reported. No patient was excluded. Patients were stratified by injury mechanism and by physiologic scoring at admission using the cardiovascular-respiratory elements of the Trauma Score (CVRS). Admission cardiac rhythm was obtained in patients with a CVRS of 0 and a Glasgow Coma Scale (GCS) score of 3. Information concerning the anatomic extent of the cardiac wound, the presence or absence of tamponade, and the degree of injury to other structures was also collected prospectively. Seventy percent of the cardiac wounds were caused by gunshots. The probability of successful resuscitation was significantly related to mechanism of injury and physiologic condition on arrival. Among patients arriving with a CVRS of 0 and a GCS score of 3, survival correlated with cardiac rhythm. Pericardial tamponade did not prove to be an independent predictor of early survival. The presence of tamponade was statistically linked to the mechanism of injury. Transport by non-official conveyance was associated with a higher CVRS on arrival. Intoxication with alcohol or cocaine had no evident effect on resuscitation probability. 相似文献
8.
Di Mauro E.C. Cootes T.F. Page G.J. Jackson C.B. 《Vision, Image and Signal Processing, IEE Proceedings -》1996,143(4):241-249
The authors present an overview of an `inspection and control' package to perform automatic quality control of industrial components, specifically electronic circuit boards. This application has grown out of a set of tools designed initially to aid the development of point distribution models (PDMs) and grey-level models (GLMs) pioneered at the Wolfson Image Analysis Unit in Manchester. These models are both generic and specific. Generic, because they can be applied to most image classification problems; specific, because they aim at the full interpretation of the variability of the objects to be modelled. The underlying vision processing techniques are based on statistical pattern matching. Two synergetic approaches have been followed. The system is trained to recognise the components from either their shape or their grey level appearance or both 相似文献
9.
AE Calogero F Nicoletti MA Palumbo N Burrello M Di Mauro M Lunetta K Bendtzen A Cianci 《Canadian Metallurgical Quarterly》1998,10(10):814-818
Myoclonus of the middle ear is a rare condition characterized by abnormal repetitive muscle contractions of the tympanic cavity. In this paper we describe what we believe is the first reported case of continuous high-frequency objective tinnitus caused by middle ear myoclonus. During exploratory tympanomastoidectomy it was hypothesized that a small dural arteriovenous malformation not identified on previous tests was the cause of the tinnitus. However, complete disappearance of the tinnitus during administration of curare for anesthesia led us to believe that the tinnitus might have been caused by myoclonus of the middle ear. Sectioning of the stapedius and tensor tympani tendons rendered the patient asymptomatic and confirmed the diagnosis of middle ear myoclonus. At follow-up of one year, the patient's quality of life had improved substantially; the tinnitus did not recur and she no longer had vertigo. 相似文献
10.
Roberto Amadini Maurizio Gabbrielli Jacopo Mauro 《Annals of Mathematics and Artificial Intelligence》2016,76(1-2):229-246
Within the Constraint Satisfaction Problems (CSP) context, a methodology that has proven to be particularly performant consists of using a portfolio of different constraint solvers. Nevertheless, comparatively few studies and investigations have been done in the world of Constraint Optimization Problems (COP). In this work, we provide a generalization to COP as well as an empirical evaluation of different state of the art existing CSP portfolio approaches properly adapted to deal with COP. The results obtained by measuring several evaluation metrics confirm the effectiveness of portfolios even in the optimization field, and could give rise to some interesting future research. 相似文献