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1.
Time series of satellite data, generated by the AVHRR (1981-1999), CZCS (1979-1985) and SeaWiFS (1998-2002), have been used to assess trends and interactions of physical and bio-geo-chemical features in the Adriatic Sea. The images were processed to estimate Sea Surface Temperature (SST) and Chlorophyll-like Pigment Concentration (CPC). Long-term composites and climatologies were derived, using fixed geographical grids and projections. The AVHRR data show an apparent warming trend, when plotting the sequence of seasonal cycles (monthly mean SST, averaged over the whole basin) against time, due to a steady rise of summer values. Considering 3 regions (north, central and south), split into east and west sections, the northern Adriatic shows high SST fluctuations (possibly associated with the cycle of winter cooling and summer warming, typical of the relatively shallow sub-basin), while the southern Adriatic exhibits a lower variability (possibly influenced by the periodic water incoming from, and outflowing to the Ionian Sea). During summer, an east-west gradient prevails, while during winter only a general north-south gradient can be found. The SeaWiFS-derived CPC values, distributions and trends appear to be consistent with the historical CZCS record. Persistent differences in the quantitative assessment of CPC for coastal waters is due to the use of improved algorithms, less influenced by the presence of dissolved organics and suspended sediments in the water column, for the processing of SeaWiFS data. Apparent incongruities of the space and time patterns in the SeaWiFS record with respect to the reference climatology, obtained by CZCS more than a decade before, occur chiefly when considering the spring bloom in the southern Adriatic and the summer development of the north Adriatic front. The comparison of the long-term times series of satellite data shows that there is a high correlation between patterns in the thermal field and in the colour field. This suggests that different surface waters, identified by the SST index, are also traced by different ecological features, identified by the CPC index. Both indices also show a high correlation with the classical cyclonic circulation scheme of the Adriatic Sea, proposing once again an intimate relationship between the water dynamics and its bio-geo-chemistry. 相似文献
2.
Ross Sparks Brian Jin Sarvnaz Karimi Cecile Paris C. R. MacIntyre 《Quality Engineering》2019,31(1):73-90
AbstractThis article focuses on monitor plans aimed at the early detection of the increase in the frequency of events. The literature recommends either monitoring the time between events (TBE) if events are rare or counting the number of events per unit non-overlapping time intervals otherwise. Some authors advocate using the Bernoulli model for rare events, applying presence or absence of events within non-overlapping and exhaustive time intervals. This Bernoulli model does improve the real-time monitoring assessment of these events compared to counting events over a larger interval, making them less rare. However this approach became inefficient if more than one event starts occurring within the intervals. Monitoring TBE is the real-time option for outbreak detection, because outbreak information is accumulated when an event occurs. This is preferred to waiting for the end of a period to count events. If the TBE reduces significantly, then the incidence of these events increases significantly. This article explores this TBE option relative to using the monitoring of counts when the TBEs are either Exponentially, Gamma or Weibull distributed for moderately low count scenarios. The article will discuss and compare the approaches of using an Exponentially Weighted Moving Average (EWMA) statistic for the TBEs to the EWMA of counts. Several robust options will be considered when the future change in event frequency is unknown. Our goal is to have a robust monitoring plan which is able to efficiently detect many different levels of shifts. These robust plans are compared to the more traditional event monitoring plans for both small and large changes in the event frequency. 相似文献
3.
Klaus van Benthem Cecile S. Bonifacio Cristian I. Contescu Nidia C. Gallego Stephen J. Pennycook 《Carbon》2011,(12):4059-4063
Aberration corrected scanning transmission electron microscopy was used to demonstrate the feasibility of imaging individual Pd atoms that are highly dispersed throughout the volume of activated carbon fibers. Simultaneous acquisition of high-angle annular dark-field and bright-field images allows correlation of the location of single Pd atoms with microstructural features of the carbon host material. Sub-Ångström imaging conditions revealed that 18 wt% of the total Pd content is dispersed as single Pd atoms in three re-occurring local structural arrangements. The identified structural configurations may represent effective storage sites for molecular hydrogen through Kubas complex formation as discussed in detail in the preceding article. 相似文献
4.
Dynamics and diversity of non-Saccharomyces yeasts during the early stages in winemaking 总被引:2,自引:0,他引:2
Zott K Miot-Sertier C Claisse O Lonvaud-Funel A Masneuf-Pomarede I 《International journal of food microbiology》2008,125(2):197-203
This detailed study observed the yeasts present in the ecological niche of "wine must". The dynamics and identity of non-Saccharomyces yeasts during the cold maceration and alcoholic fermentation of grape must were investigated under real production conditions in the Bordeaux region. Furthermore, we studied the impact of two oenological parameters on the development and diversity of non-Saccharomyces yeasts during cold maceration: temperature management and the timing of dried yeast addition. The non-Saccharomyces community underwent constant changes throughout cold maceration and alcoholic fermentation. The highly diverse non-Saccharomyces microflora was present at 10(4)-10(5) CFU/mL during cold maceration. The population increased to a maximum of 10(6)-10(7) CFU/mL at the beginning of alcoholic fermentation, then declined again at the end. The population at this point, evaluated at around 10(3)-10(4) CFU/mL, was shown to be dependent on the timing of yeast inoculation. The choice of temperature was the key factor for controlling the total yeast population growth, as well as the species present at the end of cold maceration. Hanseniaspora uvarum was a major species present in 2005 and 2006, while Candida zemplinina was very abundant in 2006. A total of 19 species were isolated. 相似文献
5.
The present study examined the separate and combined effects of alcohol and caffeine on behavioral control in a context in which preliminary cues signaled the likelihood that a response should be executed or inhibited. Social drinkers (N = 12) performed a cued go/no-go task that measured control as the quick execution of responses to go targets and sudden suppression of responses to no-go targets. Performance was tested under 3 doses of caffeine (0.0 mg/kg, 2.0 mg/kg, and 4.0 mgl/g) in combination with 2 doses of alcohol (0.0 g/kg and 0.65 g/kg). Alcohol impaired both inhibitory and activational aspects of behavioral control. Caffeine antagonized alcohol effects on response execution but had no effect on inhibitory control. The findings highlight potential differences in how activational and inhibitory aspects of behavioral control respond to drug interactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Pascale Nouchi Bruno Dany Jean -Florent Campion Louis -Anne de Montmorillon Pierre Sillard Alain Bertaina 《电信纪事》2003,58(11-12):1586-1602
Optical fiber has evolved from a not-so-transparent glass tube to an extraordinarily efficient transmission medium. It is now acknowledged as a central element of modern telecommunication being part of the whole optimization process to further improve transmission system performance and cost. In this paper, we briefly introduce transmission system optimization problematics as well as key fiber characteristics. We then review the elements of fiber design for optimized optical communication networks, including metropolitan, long and ultra-long haul applications and show how fibers have evolved over the last ten years to keep pace with more and more demanding requirement of transmission system. 相似文献
7.
We investigate both experimentally and theoretically the contribution of the different gain gratings in a self-starting self-pumped phase-conjugate Nd:YAG loop resonator. Thanks to a transient model, we show that the transmission-grating configuration is more efficient than the reflection-grating configuration, and that their temporal dynamics are different, in agreement with the experiment. Maximum extraction is obtained for the four-grating configuration. The output beam is a high-quality diffraction-limited TEM00 mode, even with severe intracavity phase aberrations, and has a single-longitudinal-mode pulse shape of ~13 ns, with maximum energy of ~130 mJ up to 30 Hz. We also investigate the role of the output coupler reflectivity on the output pulse energy and formation. Finally, the influence of the different gratings on the ability of such a self-starting loop resonator to correct for polarization distorsions is studied 相似文献
8.
This paper draws attention to the basic principles governing reflections in uniform Bragg reflectors (BR) when measured employing optical low coherence reflectometry (OLCR) technique. Using computations based on transfer matrix method (TMM), we first showed a strong spectral dependence of Bragg reflectograms on an OLCR probe spectrum. Later, this dependence is exploited to evaluate, for the first time, the coupling coefficient κ of a Bragg grating in a distributed Bragg reflector (DBR) laser on InP 相似文献
9.
Cecile?A.?M.?de?KleinEmail author Stewart?F.?Ledgard 《Nutrient Cycling in Agroecosystems》2005,72(1):77-85
In most countries, nitrous oxide (N2O) emissions typically contribute less than 10% of the CO2 equivalent greenhouse gas (GHG) emissions. In New Zealand, however, this gas contributes 17% of the nation’s total GHG emissions
due to the dominance of the agricultural sector. New Zealand’s target under the Kyoto Protocol is to reduce GHG emissions
to 1990 levels. Currently total GHG emissions are 17% above 1990 levels. The single largest source of N2O emission in New Zealand is animal excreta deposited during grazing (80% of agricultural N2O emissions), while N fertilizer use currently contributes only 14% of agricultural emissions. Nitrogen fertilizer use has,
however, increased 4-fold since 1990. Mitigation strategies for reducing N2O emissions in New Zealand focus on (i) reducing the amount of N excreted to pasture, e.g. through diet manipulation; (ii)
increasing the N use efficiency of excreta or fertilizer, e.g. through grazing management or use of nitrification inhibitors;
or (iii) avoiding soil conditions that favour denitrification e.g. improving drainage and reducing soil compaction. Current
estimates suggest that, if fully implemented, these individual measures can reduce agricultural N2O emissions by 7–20%. The highest reduction potentials are obtained from measures that reduce the amount of excreta N, or
increase the N use efficiency of excreta or fertilizer. However, New Zealand’s currently used N2O inventory methodology will require refinement to ensure that a reduction in N2O emissions achieved through implementation of any of these mitigation strategies can be fully accounted for. Furthermore,
as many of these mitigation strategies also affect other greenhouse gas emissions or other environmental losses, it is crucial
that both the economic and total environmental impacts of N2O mitigation strategies are evaluated at a farm system’s level. 相似文献
10.
A comparison of partially acetylated nanocellulose,nanocrystalline cellulose,and nanoclay as fillers for high‐performance polylactide nanocomposites 下载免费PDF全文
Jon Trifol David Plackett Cecile Sillard Ole Hassager Anders Egede Daugaard Julien Bras Peter Szabo 《应用聚合物科学杂志》2016,133(14)
Partially acetylated cellulose nanofibers (CNF) were chemically extracted from sisal fibers and the performance of those CNF as nanofillers for polylactide (PLA) for food packaging applications was evaluated. Three PLA nanocomposites; PLA/CNF (cellulose nanofibers), PLA/CNC (nanocrystalline cellulose), and PLA/C30B (CloisiteTM 30B, an organically modified montmorillonite clay) were prepared and their properties were evaluated. It was found that CNF reinforced composites showed a larger decrease on oxygen transmission rate (OTR) than the clay‐based composites; (PLA/CNF 1% nanocomposite showed a 63% of reduction at 23°C and 50% RH while PLA/C30B 1% showed a 26% decrease) and similar behavior on terms of water vapor barrier properties with 46 and 43%, respectively of decrease on water vapor transmission rate at 23°C and 50% RH (relative humidity). In terms of mechanical and thermomechanical properties, CNF‐based nanocomposites showed better performance than clay‐based composites without affecting significantly the optical transparency. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43257. 相似文献