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271.
272.
273.
Animal models of psychopathology have been extremely valuable in conceptualizing various human disorders. The human condition known as trichotillomania (compulsive hair pulling) has considerable similarities with an avian disorder called feather picking, with respect to analogous behavior, proposed etiologies, evoking cues, response to behavior therapy, and response to pharmacological treatments based on serotonin re-uptake inhibitors. We suggest that feather picking disorder has the potential to be a useful animal model of trichotillomania, and lends itself to studies on the experimental psychopathology of compulsive hair pulling. 相似文献
274.
To determine the impact of α-tomatine at the third trophic level, the following model was developed:Nomuraea rileyi (Farlow) Samson, the secondary consumer, acting onHeliothis zea (Boddie), the primary consumer, fed an artificial diet modified with α-tomatine. In vitro, the allelochemical inhibited colony formation and growth of the fungus. The in vivo test revealed that larval growth and developmental time were affected by α-tomatine andN. rileyi. Detrimental effects on pupal development were observed in larvae fed diet containing α-tomatine and also treated withN. rileyi (LC90). The fungus was detected in the hemolymph and tissue of larvae treated with two lethal concentrations (LC50 and LC90) ofN. rileyi, including those fed α-tomatine. At the LC50, α-tomatine protected larvae againstN. rileyi and increased survivorship; at the LC90, it inhibited the development ofN. rileyi, thereby reducing production of conidia. Thus, the allelochemical α-tomatine retains its antifungal qualities beyond the second trophic level, inhibiting the development ofN. rileyi inH. zea. 相似文献
275.
There are two essential ingredients in order for any telecommunications system to be able to provide Quality-of-Service (QoS)
guarantees: connection admission control (CAC) and service differentiation. In wireless local area networks (WLANs), it is
essential to carry out these functions at the MAC level. The original version of IEEE 802.11 medium access control (MAC) protocol
for WLANs does not include either function. The IEEE 802.11e draft standard includes new features to facilitate and promote
the provision of QoS guarantees, but no specific mechanisms are defined in the protocol to avoid over saturating the medium
(via CAC) or to decide how to assign the available resources (via service differentiation through scheduling). This paper
introduces specific mechanisms for both admission control and service differentiation into the IEEE 802.11 MAC protocol. The
main contributions of this work are a novel CAC algorithm for leaky-bucket constrained traffic streams, an original frame
scheduling mechanism referred to as DM-SCFQ, and a simulation study of the performance of a WLAN including these features.
This work has been partly funded by the Mexican Science and Technology Council (CONACYT) through grant 38833-A.
José R. Gallardo received the B.Sc. degree in Physics and Mathematics from the National Polytechnic Institute in Mexico City, the M.Sc. degree
in Electrical Engineering from CICESE Research and Graduate Education Center in Ensenada, Mexico, and the D.Sc. degree in
Electrical Engineering from the George Washington University, Washington, DC. From 1997 to 2000 he worked as a Research Associate
at the Advanced Communications Engineering Centre of the University of Western Ontario, London, Ontario, Canada. From May
to December 2000, he worked as a Postdoctoral Fellow at the Broadband Wireless and Internetworking Research Laboratory of
the University of Ottawa. Since December 2000, Dr. Gallardo has been with the Electronics and Telecommunications Department
of CICESE Research Center, where he is a full professor. His main areas of interest are traffic modeling, traffic control,
as well as simulation and performance evaluation of broadband communications networks, with recent emphasis on wireless local
area networks (WLANs) and wireless sensor networks (WSNs).
Paúl Medina received the B.Eng. degree from the Sonora Institute of Technology, Obregon, Mexico, and the M.Sc. degree from CICESE Research
and Graduate Education Center, Ensenada, Mexico, both in Electrical Engineering. From July to September 2005, he worked as
a Research Associate at the Broadband Wireless and Internetworking Research Laboratory of the University of Ottawa, Canada.
Mr. Medina is currently with CENI2T, Ensenada, Mexico, working as a lead engineer in projects related to routing and access control in wireless sensor networks,
as well as IP telephony over wireless LANs.
Weihua Zhuang received the B.Eng. and M.Eng. degrees from Dalian Maritime University, Liaoning, China, and the Ph.D. degree from the University
of New Brunswick, Canada, all in electrical engineering. Since October 1993, she has been with the Department of Electrical
and Computer Engineering, University of Waterloo, ON, Canada, where she is a full professor. She is a co-author of the textbook
Wireless Communications and Networking (Prentice Hall, 2003). Dr. Zhuang received the Outstanding Performance Award in 2005 from the University of Waterloo, and
the Premier’s Research Excellence Award in 2001 from the Ontario Government. She is an Editor/Associate Editor of IEEE Transactions on Wireless Communications, IEEE Transactions on Vehicular Technology, EURASIP Journal on Wireless Communications
and Networking, and International
Journal
of
Sensor
Networks. Her current research interests include multimedia wireless communications, wireless networks, and radio positioning. 相似文献
276.
Borzacchiello A Ambrosio L Netti PA Nicolais L Peniche C Gallardo A San Roman J 《Journal of materials science. Materials in medicine》2001,12(10-12):861-864
Chitosan (CHI) is a polysaccharide of beta-1,4-linked 2-amino-2-deoxy-D-glucopyranose derived by N-deacetylation of chitin in aqueous alkaline medium. The shells of crustaceans such as crabs, shrimp, and lobster are the current source of chitosan. It is known to be non-toxic, odourless, biocompatible in animal tissues and enzymatically biodegradable. For these reasons much research interest has been paid to its biomedical, ecological, and industrial applications over the past decade. However, its rigid crystalline structure, poor solubility in organic solvents and poor processability have limited its use. To broadening its range of applications, a growth research effort has been devoted to explore ways of modifying Chitosan. Here it has been reported on the synthesis of new hydrogels, obtained by self-curing chitosan with acrylic acid (AA) and methyl acrylate (MA). The hydrogels were characterized by FTIR, swelling and rheological analysis. The results of this study showed that the swelling and mechanical properties of chitosan are highly improved by the presence of poly acrylate. The swelling degree of these materials does not depend upon the ratio MA/AA. It is possible to improve and modulate the mechanical properties of the hydrogels by changing the relative MA/AA ratio. 相似文献
277.
Alvin Kier R. Gallardo Lorna S. Relleve Bin Jeremiah D. Barba Patrick Jay E. Cabalar John Andrew A. Luna Charito Tranquilan-Aranilla Jordan F. Madrid Lucille V. Abad 《应用聚合物科学杂志》2022,139(1):51451
Super water absorbent (SWA) for agricultural applications must be optimized to withstand diminishing consequences in real soil system. A 33 × 12 full factorial design and soil water retention experiments were explored to optimize agricultural SWA made from acrylic acid (AA) and cassava starch. Four synthesis parameters such as degree of neutralization (DN), AA concentration, cassava starch concentration, and absorbed dose affecting the gel properties of SWA were investigated in the experimental design. The results showed that AA concentration and DN has strong interaction effects toward the degree of swelling (DS), gel fraction (GF), and gel strength (GS) of SWA. The soil water retention of SWA reduces with time due to microbial degradation and multivalent cations present in the soil. The optimum formulation is 20% AA 10% Starch 30% DN 10 kGy has predicted values (176 ± 68 g/g DS, 93 ± 5% GF, and 137 ± 23 kPa GS) close to the experimental values (132 ± 0.2 g/g DS, 91 ± 0.2% GF, and 141 ± 88 kPa GS). The chosen optimized formulation is 20% AA 7.5% starch 30% DN 20 kGy with 46% biodegradability after 218 days and stable soil water retention compared to commercial SWAs. 相似文献
278.
Benner Peter Dufrechou Ernesto Ezzatti Pablo Gallardo Rodrigo Quintana-Ortí Enrique S. 《The Journal of supercomputing》2021,77(9):10152-10164
The Journal of Supercomputing - We investigate the factorized solution of generalized stable Sylvester equations such as those arising in model reduction, image restoration, and observer design.... 相似文献
279.
Effect of previous slurry ice treatment on the quality of cooked sardine (Sardina pilchardus) 总被引:1,自引:0,他引:1
Vanesa Losada Jorge Barros-Velázquez José M. Gallardo Santiago P. Aubourg 《European Food Research and Technology》2006,224(2):193-198
The use of slurry ice was evaluated as a technological treatment prior to cooking processing of fish. Thus, sardine (Sardina pilchardus) was stored in slurry ice for 2, 5 and 8 days. At such times, sardine specimens were taken and subjected to steam cooking, and the results were compared with those from a parallel control batch previously stored in flake ice. Quality assessment of lipid damage in cooked fish was performed by measuring the formation of free fatty acids, peroxides, thiobarbituric acid-reactive substances and interaction compounds. The volatile amines–total and trimethylamine–assessment was also carried out. A significant (p<0.05) inhibition of lipid damage–peroxides and fluorescent compounds assessment–and trimethylamine formation was observed in cooked sardine as a consequence of the preliminary treatment in slurry ice. This work opens the way to the use of slurry ice as a preliminary treatment of fish material prior to its thermal processing. 相似文献
280.
Brine freezing was applied to two small pelagic underutilised fish species (mackerel, Scomber scombrus; horse mackerel Trachurus trachurus). Rancidity development was studied during their frozen (–18 °C) storage up to 9 months, and quality change results were compared to common freezing conditions (control treatment). Fish samples treated under brine freezing conditions showed a higher lipid oxidation development (peroxide value and thiobarbituric acid index) and worse marks on some sensory attributes (general aspect, odour and colour) than control fish. However, samples treated under brine freezing conditions provided a lower lipid hydrolysis development (free fatty acid formation) and better scores for consistency. Comparison between both fish species led to a higher secondary lipid oxidation formation (thiobarbituric acid index) for mackerel, while horse mackerel showed to be more prone to interaction compound formation (fluorescence detection); however, both fish species showed the same shelf-life times (3 and 5 months for brine and control freezing conditions, respectively). As a result of the brine freezing conditions, an increase in NaCl content in white muscle of both species was observed. According to the results obtained in the present work, the brine freezing treatment is not recommended for these two small pelagic fish species. 相似文献