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101.
Isabella Nova Luca Lietti Pio Forzatti Francesca Frola Federica Prinetto Giovanna Ghiotti 《Topics in Catalysis》2009,52(13-20):1757-1761
The reduction by CO of NO x species stored over Pt–Ba/Al2O3 Lean NO x Trap systems is analysed in this work. The reaction mechanisms and pathways leading to N2 formation both under dry and wet conditions are investigated by complementary transient dynamic experiments and FTIR analyses. 相似文献
102.
Antonio Grossale Isabella Nova Enrico Tronconi Daniel Chatterjee Michel Weibel 《Topics in Catalysis》2009,52(13-20):1837-1841
The activity and the mechanism of the main reactions in the NO/NO2–NH3 SCR reacting system were comparatively investigated over a Fe- and a Cu-promoted commercial zeolite catalyst for the aftertreatment of Diesel exhausts. A dynamic micro-kinetic model in close agreement with all the details of the SCR catalytic chemistry was also developed. 相似文献
103.
Orlistat is a lipase inhibitor that is applied for treating obesity. Lipases are required for digestion and absorption of
dietary lipids and fat-soluble vitamins and carotenoids. The aim of this study was to compare the effects of orlistat therapy
on plasma concentrations of oxygenated (β-cryptoxanthin, lutein/zeaxanthin) and hydrocarbon (α-, β-carotene, lycopene) carotenoids.
Six patients with a body mass index (BMI)≥30 kg/m2 received 360 mg/d orlistat over 4.5 mon. Plasma carotenoid concentrations were determined at baseline (T
0) and after 3 (T
3) and 4.5 mon (T
4.5) along with anthropometric, dietary, and biochemical indices, including plasma lipids, retinol, α- and γ-tocopherols, and
FA. Baseline BMI was 32.7±1.97 kg/m2. Five of six patients lost weight; the average weight loss was 3.6±2.4% (P=0.47). There were no significant changes in dietary carotenoid intakes. In contrast, plasma α-and β-carotene concentrations
decreased significantly from T
0 to T
4.5 by 45% (P=0.006) and 32% (P=0.013), respectively. Plasma lycopene decreased from T
0 to T
3 but increased again from T
3 to T
4.5, while β-cryptoxanthin and lutein/zeaxanthin concentrations did not change. There were no significant alterations in tocopherol,
retinol, and FA concentrations. In conclusion, even though weight loss was not significant, orlistat therapy was associated
with significant decreases in plasma concentrations of the highly lipophilic hydrocarbon carotenoids, α- and β-carotene. 相似文献
104.
105.
106.
Bianco Isabella Panepinto Deborah Blengini Gian Andrea Onofrio Maurizio Zanetti Mariachiara 《Clean Technologies and Environmental Policy》2020,22(1):247-258
Clean Technologies and Environmental Policy - In the current context of the European Environmental legislation and standards, the automotive sector is expected to continuously improve the vehicles... 相似文献
107.
Antonio Bravo Rubén Medina Gianfranco Passariello Mireille Garreau 《Mathematics and computers in simulation》2009
A computational 4D (3D + time) model for simulating the dynamical shape of the left ventricle (LV) based on free-form deformations (FFD) techniques is described. The simulation model is useful as a teaching tool for understanding the normal left ventricle motion. The model is also useful for initializing 3D segmentation algorithms and for understanding the relation between pathologies and variation of parameters defining the ventricular function. Validation of this computational model is performed by synthesizing 4D sequences of the left ventricle, comprising the interval going from end-systole to end-diastole. From the resulting 4D shapes, several mechanical parameters such as the left ventricle volume, the radial contraction and torsion are calculated and compared with results of works previously reported based in MR-tagging images. A comparison is also performed with respect to mechanical parameters extracted from the additional time instants in the same multislice computerized tomography (MSCT) database used for extracting the LV wall surfaces required for initialization. First results show a good match between parameters compared. 相似文献
108.
C. Isabella Bovolo Simon J. Abele James C. Bathurst David Caballero Marek Ciglan George Eftichidis Branislav Simo 《Computers & Geosciences》2009,35(5):924-945
Within the European Commission-funded MEDIGRID project, Grid computing technology is used to integrate various natural hazard models and data sets, maintained independently at different centres in Europe, into a single system, accessible to users over the internet. Each centre forms a process (application) or data storage node and has been fitted with the Globus toolkit, which provides the distributed computing environment functionality that is required for the system set up. In addition, several Grid data management components were developed to allow the system to operate on different computing platforms. Access to the data and application management services is enabled through a Grid Portal. A series of portlets enable users to access the system, providing a personalised interface to the Grid. Integration of the individual models required them to be modified as web services, so as to be run remotely over the internet. As the models have different data characteristics, a common data format was adopted for creating harmonised data sets and allowing the exchange of data between the models. As an example, the Fire Spread Engine model is used to derive a map of areas that have been burnt by fire. This forms an input to the SHETRAN hydrology, soil erosion and landslide model, which in turn could provide data for other models such as vegetation regeneration. The use of the system is demonstrated for a site in south-west Spain where a large forest fire occurred on 2 August 2003. The MEDIGRID system marks an advance in the integration of independently constructed models to provide improved hazard assessment technology. 相似文献
109.
An Application of GPCC and NCEP/NCAR Datasets for Drought Variability Analysis in Iran 总被引:1,自引:0,他引:1
The lack of reliable and updated precipitation datasets is the most important limitation that hinders establishing a drought monitoring and early warning system in Iran. To overcome this obstacle, we have evaluated the applicability of GPCC and NCEP/NCAR precipitation datasets for drought analysis in Iran. For this purpose, drought variability across the country has been analyzed through the standardized precipitation index (SPI) on 12-month time scale based on the common period 1951?C2005. For each dataset, by applying the principal component analysis (PCA) to the SPI field and Varimax rotation, the studied area has been regionalized into a few distinctive sub-regions characterized by independent climatic variability. Results have been checked against observations at 32 rain gauge stations having reliable data for the study period. Both GPCC and NCEP/NCAR datasets identify the same sub-regions of drought variability and they are in good agreement with observations. However, the NCEP rotated principal component scores associated with the sub-regions show different time variability with respect to the behaviours captured by GPCC, on one hand, and observations, on the other hand. It seems that, in central Iran such differences concern mainly the period before the seventies. Thus, the results suggest that GPCC dataset is a useful tool for drought monitoring in Iran and it can be used to complement the information provided by rain gauge observations. The NCEP/NCAR reanalysis dataset shows a better agreement with observations for the period 1970?C2005 than for 1951?C2005, and its discrepancies in the regional time variability of drought with respect to GPCC and observations should be taken into account when periods before the seventies are considered. 相似文献
110.
International calls and frameworks for policies on ageing in sub-Saharan African countries, encapsulated in the UN Madrid Plan of Action on Ageing (2002) and the African Union Policy Framework and Plan of Action on Ageing (2003), have resulted in little concrete policy action. The lack of progress calls for critical reflection on the status of policy debates and arguments on ageing in the sub-region. In a context of acute development challenges and resource constraints, the paper links the impasse in policy action to a fundamental lack of clarity about how rationales and approaches for policy on ageing relate to core national development agendas. It then explicates four steps required to elucidate these connections, namely: (a) A full appreciation of key aspects of mainstream development agendas; (b) identification of ambiguities in calls for policy on ageing; (c) pinpointing of key perspectives, arguments and queries for redressing the ambiguities; and (d) addressing ensuing information needs. We argue that advocacy and research on ageing in sub-Saharan Africa need to consider the framework proposed in the paper urgently, in order to advance policy and debate on ageing in the region. 相似文献