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1.
Malatesta M Frigato E Baldelli B Battistelli S Foà A Bertolucci C 《Microscopy research and technique》2007,70(7):578-584
Reptiles represent an interesting animal model to investigate the influence of temperature on molecular circadian clocks. The ruin lizard Podarcis sicula lives in a continental climate and it is subjected to wide range of environmental temperatures during the course of the year. As consequence, ruin lizard daily activity pattern includes either the hibernation or periods of inactivity determined by hypothermia. Here we showed the rhythmic expression of two clock genes, lPer2 and lClock, in the liver of active lizards exposed to summer photo-thermoperiodic conditions. Interestingly, the exposition of lizards to hypothermic conditions, typical of winter season, induced a strong dampening of clock genes mRNA rhythmicity with a coincident decrease of levels. We also examined the qualitative and quantitative distribution of lPER2 and lCLOCK protein in different cellular compartments during the 24-h cycle. In the liver of active lizards both proteins showed a rhythmic expression profile in all cellular compartments. After 3 days at 6 degrees C, some temporal fluctuations of the lCLOCK and lPER2 are still detectable, although, with some marked modifications in respect to the values detected in the liver of active lizards. Besides demonstrating the influence of low temperature on the lizard liver circadian oscillators, present results could provide new essential information for comparative studies on the influence of temperature on the circadian system across vertebrate classes. 相似文献
2.
Serena Bianchi Sara Bernardi Antonella Mattei Loredana Cristiano Leonardo Mancini Diana Torge Giuseppe Varvara Guido Macchiarelli Enrico Marchetti 《International journal of molecular sciences》2022,23(9)
Several types of deproteinised bovine bone mineral (DBBM) are available on the market, and each one is obtained with a thermic and chemical process that can differ, achieving different results. Currently, several protocols using low temperature are suggested to reduce the possible particle crystallisation during the production process. This study aimed to evaluate the biomorphological reaction of periodontal fibroblast cultures in contact with different DBBM particles treated with a low-temperature protocol (Thermagen®) and without exposure to sodium hydroxide (NaOH). Morphological evaluation was performed using light, confocal laser, and scanning electron microscopy, and the biological reaction in terms of proliferation was performed using an XTT proliferation assay at 24 h (T1), 72 h (T2), and 7 days (T3). The morphological analysis highlighted how the presence of the materials stimulated a change in the morphology of the cells into a polygonal shape, surface reactions with the thickening of the membrane, and expression of actin. In particular, the morphological changes were appreciable from T1, with a progressive increase in the considered morphological characteristics at T2 and T3 follow-ups. The proliferation assay showed a statistical significance between the different experimental materials and the negative control in T2 and T3 follow-ups. The post hoc analysis did not reveal any differences between the materials. In conclusion, the grafts obtained with the low-temperature extractions protocol and not exposed to NaOH solution showed positive morphological reactions with no differences in the sizes of particles. 相似文献
3.
4.
Cristiano Araujo Millena Gomes Edna Barros Sandro Rigo Rodolfo Azevedo Guido Araujo 《Design Automation for Embedded Systems》2005,10(4):253-283
This paper[3.5pc] presents the Platform Designer (PD) framework, a set of SystemC based tools that provide support for modeling,
simulation and analysis of multiprocessor SoC platforms (MPSoC), at different abstraction levels. PD provides mechanisms for
interconnection specification, process synchronization and communication, thus allowing the modeling of a complete platform,
in a unified environment. To do that it uses an extension of the ArchC ADL and acsys, a tool that enables the automatic generation
of a SystemC simulator of the platform. The main advantages of this approach are twofold. First, designers have more flexibility
since they can integrate and configure different processors to the platform, using a single environment. Second, it enables
a faster design space exploration, given that it automatically generates SystemC simulators of whole platforms at distinct
abstraction levels. A number of platform variations can be tried out with minor design changes, thus reducing design time.
Experimental results show the suitability of the platform simulator for design space exploration. Real applications (with
medium complexity) run in the platform in few minutes. Combined with the facility to generate platforms with minor changes,
this feature allows an improvement of the design space exploration. 相似文献
5.
Cristiano J.J. White C.C. Jr. Liker J.K. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2001,31(3):366-382
In the product design and development process, quality function deployment (QFD) provides a comprehensive, systematic approach to support the design of new products intended to meet or exceed customer expectations. The authors use multiattribute value theory to support new product design and hence to augment a design team's experience and judgment. We introduce the concept of a target set, the set of all value score vectors that are at least as preferred as the value score vectors of any of the given design alternatives. Assuming mutually preferential independence, we characterize the target set and indicate how it can be used to support selecting targets: 1) for the level of customer satisfaction to be attained by the new product, for each customer requirement and 2) for design requirements, presumably based in part on information from engineering competitive assessments. We then use the target set concept to augment the product planning phase of QFD. The concepts are illustrated and evaluated through the retrospective application of the methodology to an actual surgical product (universal converter). Although the analysis was performed retrospectively, without knowledge of the market success of the product and its competitors, the results were consistent with product acceptance and provided valuable insights to the lead engineer 相似文献
6.
Maria?Da?Gloria Flores Marcelo?Negreiros Luigi?CarroEmail author Altamiro?A.?Susin Felipe?R.?Clayton Cristiano?Benevento 《Journal of Electronic Testing》2005,21(3):283-290
This paper presents a low cost test method for the static and dynamic characterization of analog-to-digital converters. The method is suitable for implementation in a SoC environment, as a built-in self test (BIST) solution. In the proposed approach, noise is used as the test signal. Theory of operation and practical results demonstrating the effectiveness of the method for INL, DNL, THD and SINAD characterization are presented. The BIST surface overhead caused by the noise generator is only 7.4% of the ADC total area. The reduced number of data samples required allows a reduction of about 7.5× in test time, in comparison to the histogram method.Maria da Gloria Cataldi Flores was born in Santa Maria, Brazil, in 1978. She received the electrical engineering degree in 2000 from Universidade Federal de Santa Maria (UFSM) and the M.S. degree engineering in 2003 from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil. Since then, she has been working as a design engineer in an EAS Supply brazilian company. Her main research interests include mixed-signal and analog testing and digital signal processing.Marcelo Negreiros was born in Porto Alegre, Brazil, in 1969. He received the electrical engineering degree in 1992 and the M.S. degree engineering in 1994, both from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil. Since then he was been working as an associate researcher in the Signal Processing Lab. (LaPSI) of the Electrical Engineering Department at UFRGS. Since 2000 he also works toward a Ph.D. in Computer Science from UFRGS. His main research interests include mixed-signal and analog testing and digital signal processing.Luigi Carro was born in Porto Alegre, Brazil, in 1962. He received the Electrical Engineering and the M.Sc. degrees from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil, in 1985 and 1989, respectively. From 1989 to 1991 he worked at ST-Microelectronics, Agrate, Italy, in the R&D group. In 1996 he received the Ph.D. degree in the area of Computer Science from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil. He is presently a lecturer at the Electrical Engineering Department of UFRGS, in charge of Digital Systems Design and Digital Signal processing disciplines at the graduate and undergraduate level. He is also a member of the Graduation Program in Computer Science of UFRGS, where he is responsible for courses in Embedded Systems, Digital Signal Processing, and VLSI Design. His primary research interests include mixed-signal design, digital signal processing, mixed-signal and analog testing, and fast system prototyping. He has published more than 90 technical papers in those topics and is the author of the book Digital Systems Design and Prototyping (in portuguese).Altamiro A Susin was born in Vacaria-RS, Brazil, in 1945. He received the Electrical Engineering and the MSc. degrees from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil, in 1972 and 1977, respectively. Since 1968 he worked in the start up of Computer Centers of two local Universities. In 1981 he got his Dr. Eng degree from Institut National Polytechnique de Grenoble-France. He is presently a lecturer at the Electrical Engineering Department of UFRGS, in charge of Digital Systems Design disciplines at the graduate and undergraduate level. He is also a member of the Graduation Program in Computer Science of UFRGS, where he is responsible by courses in VLSI Architecture and is also thesis director. His main research interests are Integrated Circuit Architecture, Embedded Systems, Signal Processing with more than 50 technical papers published in those domains. He is/was responsible for several R&D projects either funded with public and/or industry resources.Felipe Ricardo Clayton received the B.S. degree in Electrical Engineering from State University of Campinas (UNICAMP), Brazil, in 1986. He worked at CPqD (Brazilian PTT R&D Center) till 1996 designing analog and mixed signal circuits for telecom and automotive applications. From 1997 to the second half of 1998, he worked at Instituto Superior Técnico (IST), Lisbon, Portugal, under the guidance of Prof. Carlos Azeredo Leme on development of CMOS RF circuits. Since October 1998 he had worked for Motorola SPS. Now he is head of the Power Managment Group at Freescale.Cristiano Benevento received his B.S. degree in Electrical Engineering from Universidade Estadual de Campinas (Unicamp), Brazil, in 1997. He worked at Motorola Cellular Infrastructure Group until August 2000 as a Systems Engineer. He joined Motorola Semiconductor Product Sector in August 2000 as IC Designer for Power Management Group and is now at Freescale. 相似文献
7.
Cristiano Silva do Nascimento Brenda N. Santos Sueli Rodrigues 《International Journal of Food Science & Technology》2022,57(8):5186-5194
In the present study, a prebiotic acerola juice containing gluco-oligosaccharides and dextran was produced and processed by high-intensity ultrasound (HIUS). After a simulated in vitro digestion, the gluco-oligosaccharides and dextran maintained 90% and 80% of their initial concentration in all prebiotic’s juices. At the same time, Vitamin C and phenolic compounds concentration increased significantly by 19% and 7% (P < 0.05). After the in vitro digestion, the prebiotic juice HIUS processed by 10 min showed the highest increase in gluco-oligosaccharides and bioactive compound concentrations. The HIUS processing imparted some dextran hydrolysis and improved its fermentability by Lacticaseibacillus casei. Gluco-oligosaccharides were extensively consumed as substrate in simulated intestinal conditions, promoting the L. casei NRRL B-442 growth and production of organic acids and short-chain organic acids. The prebiotic juice HIUS processed for 6 min showed the best responses regarding the metabolism of L. casei NRRL B-442. The results showed high-intensity ultrasound processed acerola juices containing gluco-oligosaccharides and dextran as a prebiotic food. 相似文献
8.
Determination of Toxic Elements in Nuts by Inductively Coupled Plasma Mass Spectrometry after Microwave-Induced Combustion 总被引:2,自引:0,他引:2
Aline L. H. Muller Cristiano C. Muller Fernanda Lyra Paola A. Mello Marcia F. Mesko Edson I. Muller Erico M. M. Flores 《Food Analytical Methods》2013,6(1):258-264
Microwave-induced combustion (MIC) of nuts in closed vessels was evaluated as a sample preparation method for further determination of As, Cd, and Pb by inductively coupled plasma mass spectrometry (ICP-MS) and Hg by flow injection cold vapor generation coupled to ICP-MS (FI-CVG–ICP-MS). Conventional microwave-assisted acid digestion (MW-AD) in pressurized vessels was also used for results comparison. Samples were wrapped in polyethylene films and combusted using 20 bar of oxygen and 50 μl of 6 mol l?1 ammonium nitrate as aid for ignition. Sample masses up to 500 mg of hazelnuts, almonds, cashew nuts, Brazil nuts, and walnuts were combusted using 7 mol l?1 HNO3 as absorbing solution. Accuracy was evaluated using certified reference materials and an agreement better than 96% was obtained for all analytes. Using MIC, it was possible to obtain lower limits of detection (LODs) in comparison with those obtained by MW-AD. The LOD obtained using MIC was 3, 2, and 6 ng g?1 for As, Cd, and Pb, respectively. The LOD for Hg by FI-CVG–ICP-MS was 7 ng g?1. Residual carbon content obtained after decomposition by MW-AD and MIC was 20% and lower than 1.5%, respectively, showing the high efficiency of MIC and allowing the determination of toxic elements in samples with high fat content. With the use of MIC up to eight samples could be processed simultaneously and only diluted nitric acid was required minimizing physical interferences, reagent consumption, and waste generation. 相似文献
9.
10.
Extrusion of Rice,Bean and Corn Starches: Extrudate Structure and Molecular Changes in Amylose and Amylopectin 总被引:1,自引:0,他引:1 下载免费PDF全文
Nathan Levien Vanier Varatharajan Vamadevan Graziella Pinheiro Bruni Cristiano Dietrich Ferreira Vânia Zanella Pinto Koushik Seetharaman Elessandra da Rosa Zavareze Moacir Cardoso Elias Jose De J. Berrios 《Journal of food science》2016,81(12):E2932-E2938
The objective of this study was to evaluate the effects of starch source and amylose content on the expansion ratio, density, and texture of expanded extrudates, as well as to investigate the structural and molecular changes that occur in starch granules as a function of extrusion. The starches employed were rice starches (8%, 20%, and 32% amylose), carioca bean starch (35% amylose), and Hylon V® corn starch (55% amylose). The extrudates from rice starches containing 20% and 32% amylose exhibited the highest expansion ratio, while, extrudates from Hylon V® corn starch containing 55% amylose exhibited the lowest expansion ratio. The hardness values of the extrudates with 55% amylose were twice those of the extrudates with 20%, 32%, and 35% amylose. An additional finding was that although the amylopectin promoted the expansion of the gelatinized starch matrix, it failed to strengthen and sustain the walls of the extrudate bubbles during expansion. 相似文献