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101.
102.
Sheela A. Moses Letha Janaki Sabu Joseph Jairaj P. Gomathi Justus Joseph 《Lakes & Reservoirs: Research and Management》2013,18(2):145-153
The remote sensing technique provides a rapid and relatively inexpensive means of identifying silted areas in large water bodies, in order that desilting activities can be effectively conducted. This study developed lake bathymetry for a selected lake system (Akkulam–Veli Lake, Kerala, India) from the Indian Remote Sensing (IRS P6‐LISS III) satellite imagery, using an artificial neural network (ANN) model. The water depth was measured for 17 months at different points in the lake on the same date of overpass of the IRS satellite. The satellite imageries obtained for 12 December 2007 and 16 February 2009 were identified as cloud‐free images. ANN models were developed with the four input series of radiance values from green, red, NIR and MIR bands observed for the satellite imagery obtained on 12 December 2007 at the sampling sites, with actual water depth measurements also being taken on the same date. A three‐layered feed forward neural network with back propagation training algorithm was developed for this study. To train the model, it was run several times by changing the number of neurons, learning rate and the momentum constants until the mean square error was minimum. When the number of neurons is increased to 35, and the logsig function is used as ANN transfer function, the error becomes minimum. To test the model, the developed ANN was run for a new set of input from the satellite imagery taken on 16 February 2009. Comparing the predicted and measured values for the same sites for the same day, it was found that the model is best suited for predicting water depth using ANN and the radiance values for four bands of IRS satellite imagery. The results of this study indicated that, for the shallow lake with lower depth, the difference between the actual and predicted value was considerable. In contrast, this was not the case where the lake water depth was greater, indicating an increased prediction accuracy with ANN with increasing depths for shallow lakes. A bathymetry map prepared with ANN indicated only the lake shoreline, as well as the shallow littoral zones. The approach used in this study requires further refinement, including further of the model based on using more field measurements to obtain a better bathymetry map. 相似文献
103.
R. K. Jena 《Behaviour & Information Technology》2018,37(10-11):978-992
ABSTRACTBusiness Management Education in India has shown an upward growth trend in the last couple of decades. Due to the diverse nature of the course, students from diverse academic backgrounds are being admitted to the course. Therefore, differences in students’ abilities and their learning styles have a significant effect on their learning outcomes. Meanwhile, with the development of learning technologies, learners can be provided a more effective learning environment to optimise their learning. The purpose of this study was to develop a model to automatically detect the students’ learning styles from their personal, academic and social media data and make recommendations for students, teachers, educators and administrators for overall improvement of learning outcomes. Data analysis in this research was represented using data collected from post-graduate business management students in India. A 10-fold cross-validation was used to create and test the models. The data were analysed by R and R-Studio. Classification accuracy, Precision, Recall, Kappa, ROC curve and F measure were observed. The results showed that the accuracy of classification by the C4.5 technique had the highest value at 95.7%, and it could be applied to develop Felder–Silverman’s learning style while taking into consideration students’ academic, personal information and social media preferences. 相似文献
104.
Environmental characteristics and phytoplankton productivity of a shallow Ramsar‐site floodplain in the western Himalaya
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Mohammad A. Khan 《Lakes & Reservoirs: Research and Management》2015,20(2):69-76
Hokersar wetland (altitude of 1584 masl), a shallow (0.5 m) floodplain waterfowl habitat in Kashmir, India, gained international importance in 2005 with its declaration as a Ramsar site. Although isolated in the western Himalayan mountains, it is being impacted by a silt‐laden river (Doodhganga). Human activities, not the least of which is affected by the closeness of the wetland to suburban areas, have gradually altered its trophic state. Its alkaline‐ and calcium‐rich waters contain many planktonic diatoms, green algae and cyanobacteria. Nitrate–nitrogen and total phosphorus concentrations are high (370–4750 and 101–968 μg L?1, respectively). A pronounced seasonal cycle in phytoplankton production (g C m?2 day?1) was evident in a minimum value of 0.38 (Jan–Feb, 2002) and a maximum value of 4.02 (July, 2002), closely paralleling the seasonal cycles of temperature and light. The photosynthetic efficiency of the wetland was highest (1.97%) during the summer. The annual phytoplankton production of this wetland ecosystem was 210 × 102 KJ m?2, suggestive of a meso‐eutrophic status. 相似文献
105.
Dhananjay?Dendukuri Levente?L.?DiosadyEmail author 《Journal of the American Oil Chemists' Society》2003,80(3):287-294
New microfiltration (MF)-based aqueous processes for the extraction of oil-free protein isolates from full-fat, dehulled mustard
flour have been developed. The processes used hydrophilic MF membranes to separate oil and protein. The most successful processing
sequence consisted of alkaline extraction of oil and protein from the flour at pH 11, centrifugation to remove undissolved
solids, and an initial microfiltration step to separate oil and dissolved protein. This was followed by proteolytic enzyme
treatment of the retentate and a second-stage MF step to recover further protein. The proteolytic enzyme treatment was designed
to break aggregated proteins into smaller fractions to permit their passage through the MF membrane. The permeates from the
two microfiltration steps were ultrafiltered to concentrate the protein and remove antinutritional compounds and highly fragmented
peptides. With this process, 60% of the protein originally in the flour was separated from the oil phase. Approximately 40%
of the protein present in the flour was recovered in the form of two oil-free protein isolates—a soluble protein isolate containing
91% protein and a precipitated protein isolate containing 100% protein. The process proves the potential of MF as an effective
method of extracting oil-free protein isolates from oilseeds without the use of organic solvents.
Based on a presentation at the 16th Annual Meeting of the Canadian Section of AOCS held in Winnipeg, Manitoba, Canada, September
29–October 1, 2001. 相似文献
106.
An evaluation of supercritical fluid extraction as an analytical tool to determine fat in canola,flax, solin,and mustard 总被引:1,自引:0,他引:1
Véronique?J.?BarthetEmail author James?K.?Daun 《Journal of the American Oil Chemists' Society》2002,79(3):245-251
Supercritical fluid extraction (SFE) with carbon dioxide was used to extract oil from soft oilseeds (flax, solin, canola,
and mustard). Oil content determinations from the SFE method AOCS Am 3–96, with and without ethanol as a modifier, were compared
to results obtained with an exhaustive extraction using petroleum ether (FOSFA as in AOCS Am 2–93). Without the modifier,
oil recoveries using SFE were 10 to 15% lower than oil contents by the FOSFA method for the flax and canola samples. For mustard,
the oil recoveries by SFE were about 20 to 30% lower than oil contents by the FOSFA method. In the presence of the modifier,
oil recoveries for flax and canola were about 3% lower than the FOSFA recoveries. Varying the time, temperature, and amount
of modifier (ethanol) showed that recoveries increased with time, pressure, temperature, and amount of modifier independently
of the oilseeds tested. Kinetics of the SFE extraction showed that the oil recoveries increased with the extraction time and
reached a plateau after 60 min. Multiple extractions (2×30 min), however, gave better recoveries than a single extraction
for the same amount of time (60 min). The best results were obtained using multiple extractions without modifier or a combination
of multiple extractions first without and then with 15% modifier. Under these last two conditions, oil recoveries were close
to 100% for flax, solin, and canola, but mustard oil recoveries were still 10% lower than recoveries using the FOSFA method.
Mustard samples gave the lowest oil recovery from SFE when compared to FOSFA method recoveries whatever conditions were tested,
suggesting a matrix effect on the oil recovery. The acyl lipid content of the various extracts was studied using the sum of
all FA expressed as TAG as a measure of acyl lipid extraction. The acyl lipid contents of the extracts were close to 100%
when no modifier was used during the SFE. In the presence of modifier, the acyl lipid contents of the extracts were 10 to
15% lower than the results obtained without modifier. The amount of acyl lipid in the extract decreased as the quantity of
modifier increased. This suggests that increasing the ethanol modifier increased the amount of polar compounds extracted without
significantly increasing the total amount of lipids. The FA profiles were constant throughout the various extraction procedures. 相似文献
107.
Renwick JA Zhang W Haribal M Attygalle AB Lopez KD 《Journal of chemical ecology》2001,27(8):1575-1583
The host plants of the native American butterfly, Pieris napi oleracea, include most wild mustards. However, garlic mustard, Alliaria petiolata, a highly invasive weed that was introduced from Europe, appears to be protected from this insect. Although adults will oviposit on the plant, most larvae of P. n. oleracea do not survive on garlic mustard. We used feeding bioassays with different larval stages of the insect to monitor the isolation and identification of two bioactive constituents that could explain the natural resistance of this plant. A novel cyanopropenyl glycoside (1), alliarinoside, strongly inhibits feeding by first instars, while a flavone glycoside (2), isovitexin-6-D--glucopyranoside, deters later instars from feeding. Interestingly, the first instars are insensitive to 2, and the late instars are little affected by 1. Furthermore, differential effects of dietary experience on insect responses suggest that 1 acts through a mechanism of post-ingestive inhibition, whereas 2 involves gustatory deterrence of feeding. 相似文献
108.
Comparison of combustion and Kjeldahl methods for determination of nitrogen in oilseeds 总被引:1,自引:0,他引:1
James K. Daun Douglas R. DeClercq 《Journal of the American Oil Chemists' Society》1994,71(10):1069-1072
The recent development of combustion-type nitrogen analyzers capable of handling relatively large samples with semi automatic
operation offers a potential replacement for the Kjeldahl method for direct determination of nitrogen. Nitrogen analyses for
canola seed, flaxseed, sunflower seed, mustard seed and soybeans on a LECO (St. Joseph, MI) FP-428 Nitrogen Analyzer were
evaluated against results from the Grain Research Laboratory's (GRL) Kjeldahl system. The nitrogen analyzer gave significantly
higher values than the Kjeldahl method, resulting in a correction of low values in the GRL Kjeldahl, caused by the inability
to use mercury as catalyst. The standard error for results from the analyzer was comparable to that for the Kjeldahl method.
The nitrogen analyzer also was faster than the Kjeldahl method and had less environmental impact. The combustion method has
replaced the Kjeldahl method for routine nitrogen determinations in oilseed surveys conducted by the GRL.
Presented at the 84th AOCS Annual Meeting & Expo, April 27, 1993, Anaheim, California. 相似文献
109.
During commercial solvent extraction of oil from an oil-seed, it is necessary to determine oil content in the miscella, drawn
intermittently from the extractor, to obtain an overall extraction rate. We measured optical density, specific gravity, refractive
index and viscosity of miscella of different known oil concentrations. These four characteristics were measured by calculating
deviations from the actual values. The deviations were maximum for optical density, intermediate for specific gravity and
viscosity, and small for refractive index, suggesting the latter to be an appropriate rapid method of determining miscella
oil content. 相似文献
110.
P. E. A. Teal R. R. Heath B. D. Dueben J. A. Coffelt K. W. Vick 《Journal of chemical ecology》1995,21(6):787-799
Extracts of sex pheromone glands obtained from females ofPloida interpunctella contained detectable amounts of (Z,E,)-9,12-tetradecadien-1-ol acetate (Z9,E12–14:Ac) and (Z,E.)-9,12-tetradecadien-1-ol (Z9,E12–14:OH) 4 hr prior to the first scotophase after adult emergence. The amount of pheromone increased during the first 4 hr of the scotophase and then declined to low levels during the subsequent photophase. Decapitation of females immediately after emergence, prior to expansion of the wings, inhibited production of pheromone during the subsequent 48 hr. Injection of extracts of the heads of 1-day-old females ofP. interpunctella of partially purified extracts of the cephalic ganglia of females of the corn earworm moth into decapitated females stimulated production of bothZ9,E12–14:Ac andZ9,E12–14:OH as well as production of (Z,E)-9,12-tetradecadienal (Z9,E12–14:Al). This aldehyde was subsequently identified from extracts of pheromone glands obtained from naturally calling females as well as from volatiles emitted by calling females. Studies on the terminal steps in biosynthesis of the pheromone showed thatZ9,E12–14:OH was produced from the corresponding acetate and thatZ9,E12–14:Al was produced from the alcohol via the action of an oxidase(s). 相似文献