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91.
Nikolaos Gougoulias Ioannis Vagelas Ioannis Vasilakoglou Fotios Gravanis Aida Louka Eleni Wogiatzi Professor Nikolaos Chouliaras 《Journal of the science of food and agriculture》2010,90(2):286-290
BACKGROUND: Oregano essential oil and neem have been reported to be effective against soil‐borne pathogens and nematodes. The possibility of having an effect on soil properties was the aim of this investigation. Moreover, thiram, a common widely used chemical pesticide, was used for comparison. RESULTS: The effects of all three above‐mentioned substances were investigated during an incubation experiment, for 15 weeks. Crushed neem pellets were added at 1.0, 2.0 or 3.0 g per 50 g of soil. Oregano dry matter was applied at 0.2, 0.4 or 0.6 g per 50 g of soil. Finally, thiram was applied at 0.1, 0.2 and 0.3 g per 50 g of soil. The addition of neem resulted in a decrease in organic carbon mineralisation, higher than that of oregano, but not as prominently as thiram. The addition of neem resulted in an increase in the content of nitrate, organic P, bioavailable P, bioavailable K and bioavailable Mn. Oregano had a slight negative effect on organic matter biodegradation, but caused an increase of nutritional mineral elements. Microbe colonies in soil were increased by the addition of neem cake granules, whereas oregano and thiram treatments caused a decrease. The addition of thiram reduced nitrate and available Mn contents, but at the lowest dose increased organic P and available K. Thiram reduced prominently available Cu at the upper rates, but it increased these forms at the lowest rate, while available Zn content was increased in two lowest rates. CONCLUSION: The results of this study indicated that neem or oregano could be applied to the soil without any extremely negative effect on the available forms of nutritional mineral elements, as thiram does. Copyright © 2009 Society of Chemical Industry 相似文献
92.
Ioannis Karaouzas Christos Theodoropoulos Leonidas Vardakas Eleni Kalogianni Nikolaos Th. Skoulikidis 《河流研究与利用》2018,34(4):291-299
This review presents the main results of a 10‐year research study conducted in a Mediterranean intermittent basin (Evrotas River). By assembling the main outcomes of past and ongoing research projects, this study provides an overview of multiple stressor effects, with emphasis on water scarcity, focusing on hydro‐biogeochemical processes, as well as on spatial and temporal variations in benthic macroinvertebrates and fish fauna. The major impact in the basin has been the over‐exploitation of surface and groundwater resources, which, in combination with droughts, has resulted in the recurrent artificial desiccation of large parts of the hydrological network. The response to intermittency of the macroinvertebrate fauna is characterized by high resilience through various drought‐resistant evolutionary mechanisms, with assemblages recovering successfully after recurrent droughts. However, when pollution is evident in combination with drought, effects on benthic species richness, abundance, and assemblage structure can be severe. Similarly, pollution and water stress may result in massive fish mortalities due to hypoxic conditions, with fish populations requiring long periods to recover. However, the fish fauna appears to be relatively resilient to drought‐driven reach‐scale desiccation, and ultimately recovers, provided that aquatic refugia are available to supply colonists and that there are no physical barriers impeding recolonisation. Appropriate conservation measures are urgently required to address the effects of recurrent bouts of water stress, as well as of other stressors on the freshwater communities of the Evrotas River, both at the level of water management and of water policy and at the local and the national level. 相似文献
93.
Dimitra Taliadourou Vassilios Papadopoulos Eleni Domvridou Ioannis N Savvaidis Michael G Kontominas 《Journal of the science of food and agriculture》2003,83(13):1373-1379
The effect of filleting on the microbiological, chemical and sensory properties of aquacultured sea bass (Dicentrarchus labrax) stored in ice was studied. Pseudomonads, H2S‐producing bacteria (including Shewanella putrefaciens) and Brochothrix thermosphacta were the dominant bacteria at the end of the 16 day storage period in ice for both whole ungutted and filleted sea bass. Enterobacteriaceae were also found in the spoilage microflora of whole ungutted and filleted sea bass, but their counts were always lower than those of pseudomonads, H2S‐producing bacteria (including S putrefaciens) and B thermosphacta. Total viable counts for whole ungutted sea bass were always lower than those for filleted sea bass samples. Of the chemical indicators of spoilage, TMA (trimethylamine) values of whole ungutted sea bass increased very slowly, whereas significantly higher values were obtained for filleted samples, with respective values of 0.253 and 1.515 mg N per 100 g muscle being reached at the end of their shelf‐life (days 13 and 9 respectively). TVB‐N (total volatile basic nitrogen) values showed a slight increase for whole ungutted sea bass during storage, reaching a value of 26.77 mg N per 100 g muscle (day 13), whereas for filleted fish a corresponding value of 26.88 mg N per 100 g muscle was recorded (day 9). TBA (thiobarbituric acid) values increased slowly for whole ungutted and filleted sea bass samples throughout the entire storage period, reaching final values of 4.48 (day 13) and 13.84 (day 9) mg malonaldehyde kg?1 respectively. Sensory assessment of raw fish using the EC freshness scale gave a grade E for up to 5 days for whole ungutted sea bass, a grade A for a further 4 days and a grade B for an additional 4 days, after which sea bass was graded as C (unfit). Overall acceptability scores for odour, taste and texture of cooked whole ungutted and filleted sea bass decreased with increasing time of storage. The results of this study indicate that the shelf‐life of sea bass stored in ice, as determined by overall acceptability sensory scores and microbiological data, is 8–9 days for filleted and 12–13 days for whole ungutted fish. Copyright © 2003 Society of Chemical Industry 相似文献
94.
Al Otaiba Stephanie; Petscher Yaacov; Pappamihiel N. Eleni; Williams Rihana S.; Dyrlund Allison K.; Connor Carol 《Canadian Metallurgical Quarterly》2009,101(2):315
This study examines growth in oral reading fluency across 2nd and 3rd grade for Latino students grouped in 3 English proficiency levels: students receiving English as a second language (ESL) services (n = 2,182), students exited from ESL services (n = 965), and students never designated as needing services (n = 1,857). An important focus was to learn whether, within these 3 groups, proficiency levels and growth were reliably related to special education status. Using hierarchical linear modeling, the authors compared proficiency levels and growth in oral reading fluency in English between and within groups and then to state reading benchmarks. Findings indicate that oral reading fluency scores reliably distinguished between students with learning disabilities and typically developing students within each group (effect sizes ranging from 0.96 to 1.51). The growth trajectory included a significant quadratic trend (generally slowing over time). These findings support the effectiveness of using oral reading fluency in English to screen and monitor reading progress under Response to Intervention models, but also suggest caution in interpreting oral reading fluency data as part of the process in identifying students with learning disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Dr. Eleni Loizou Dr. Popi Nicolaidou Kanari Georgia Kyriacou Maria Aletrari 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,5(3-4):459-463
Directive 98/83/EC concerning the drinking water quality and Directive 80/777/EC for Natural Mineral Water demand strict control and monitoring for the presence of metals. The State General Laboratory as the official control laboratory (Accredited by ISO 17025:2005) implements a national monitoring program in order to ensure that the drinking and natural mineral water quality satisfy the requirements of the respective Directives. The National Monitoring program covers mainly metals such as Pb, Cd, Cr, Ni, As, Se, Sb, Hg, Mn, Cu, Fe, Al and B in water supplied for human consumption either by distribution networks, vending machines, mobile water containers, ground water intended for human consumption as well as bottled water. The determination of metals in water by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) is a technique that successfully meets the requirements of the above Directives as it is a very powerful tool for the measurement of metals at very low concentrations with high accuracy and precision. The results obtained indicate that metal concentrations in drinking and bottled water examined were by far, below the acceptable legal limits and even below the relevant detection limits. However, in samples of bottled natural mineral water, high boron concentration were determined and risk assessment was performed due to the absence of relevant legal limits. The present paper demonstrates the steps undertaken by the General Water Analysis Laboratory of the SGL for the validated method used by ICP-MS in the determination of trace metals including boron in drinking and bottled water. 相似文献
96.
97.
Eleni Tomai Isabelle Herlin Jean‐Paul Berroir Poulicos Prastacos 《International journal of remote sensing》2013,34(13):3315-3330
In this paper, we introduce the idea of documenting operational chains for land degradation assessment using ontologies. We believe that this process will help end users better understand the application domain characteristics and evaluate the results of the assessment process. Since the application domain is wide, various operational chains for land degradation assessment and their associated documentation exist, according to different options. This parameterization process causes the development of different ontologies, which nonetheless are, to a certain extent, linked because of the common software components of the corresponding operational chains. We therefore propose a hierarchical structure of these ontologies; so that several requirements such as understanding of expert knowledge interconnections and of application domain variety, documentation and assimilation of new expert knowledge, and reusability of software components become feasible. 相似文献
98.
Condition monitoring, within the power industry, is essential to ensure continuous operation and health of electrical plans. This is a complex activity that requires the combination of different artificial intelligence techniques. This article describes a multiagent framework to support such a condition-monitoring approach. The resulting condition monitoring multiagent system (COMMAS) was applied to two different case studies, to monitor the start-up sequences of industrial gas turbines and identification of partial discharge signal defects in gas insulated substations. 相似文献
99.
Stefanos Gritzalis Sokratis K. Katsikas Dimitrios Lekkas Konstantinos Moulinos Eleni Polydorou 《Computers & Security》2000,19(8):731
In this paper, the unified, abstract KEYSTONE Public Key Infrastructure is presented. This architecture consists of a reference model, a functional architecture specification, and a set of technologies that can be used for implementing the functional units, along with all relevant standards. It was derived within the course of the KEYSTONE project, which was funded by the European Commission under the Electronic Trust Services II Programme. The proposed PKI architecture guarantees openness, scalability, flexibility, extensibility, integration with existing TTP and information infrastructure, transparency and, above all, security. Thus, it enjoys all the desirable characteristics and fulfils all those criteria that are essential for a PKI to constitute a successful framework for the development of inter-domain and international Trusted Services. 相似文献
100.
Eleni Patouni Sophie Gault Markus Muck Nancy Alonistioti Konstantina Kominaki 《电信纪事》2007,62(9-10):1099-1120
The Autonomic Communications concept forms one promising solution to accommodate the increased complexity of legacy and emerging systems, fostering the automation and minimizing the need for human intervention. This notion implies the introduction of advanced mechanisms for autonomic decision making and self-configuration. The focus of this work is on the introduction of an advanced reconfiguration framework for the support of the following functionalities: i) efficient strategies of terminal attachment to heterogeneous wireless systems are proposed dependent on the evaluation of input stimuli from the surrounding telecom environment. ii) it is shown how to enable optimized selection and attribution of resources, iii) the application of new device configuration is examined, proposing a framework for dynamic protocol stack adaptation. It is indeed necessary to introduce a framework that will enable, policy based reconfiguration decisions supporting dynamic and optimal discovery, download and replacement of necessary protocol functionality. In this context, legacy management and control mechanisms should be enriched with such features operating in either terminal or network equipment. Namely, this contribution discusses cognitive reconfiguration management issues by introducing two basic reconfiguration units encapsulated in a unified management and control architecture: i) the component based protocol stack reconfiguration framework and ii) the resource usage optimization unit. Simulation and performance results presented in the paper prove the technical feasibility of the proposed mechanisms as well as the optimization of reconfiguration actions. 相似文献