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101.
Dr. Stephanie M. Jensen Dr. Flora W. Kimani Dr. John C. Jewett 《Chembiochem : a European journal of chemical biology》2016,17(23):2216-2219
Chemical crosslinking is a versatile tool for the examination of biochemical interactions, in particular host–pathogen interactions. We report the critical first step toward the goal of probing these interactions by the synthesis and use of a new heterobifunctional crosslinker containing a triazabutadiene scaffold. The triazabutadiene is stable to protein conjugation and liberates a reactive aryl diazonium species upon irradiation with 350 nm light. We highlight the use of this technology by modifying the surface of several proteins, including the dengue virus envelope protein. 相似文献
102.
Effect of Soybean 7S Protein Fractions, Obtained from Germinated and Nongerminated Seeds, on Dough Rheological Properties and Bread Quality 总被引:1,自引:0,他引:1
Emigdio C. López-Guel Flora Lozano-Bautista Rosalva Mora-Escobedo Reynold R. Farrera-Rebollo Jorge Chanona-Pérez Gustavo F. Gutiérrez-López Georgina Calderón-Domínguez 《Food and Bioprocess Technology》2012,5(1):226-234
Germinated soybean flour has been proposed for use in bread making as a product to improve bread quality when small amounts
are added to wheat flour. However, it is not clear which soybean components promote this action, and how these components
may influence bread quality. The aim of this work was to evaluate the effect of the addition of soybean 7S protein fraction
obtained from germinated and nongerminated seeds in dough rheological properties (farinographic and extensographic) and bread
quality, including loaf volume, texture (firmness, compression force, resilience), colour (L*, a*, b*), crumb grain structure
(cell density, mean cell area, shape factor), and consumer acceptance (sensory analysis). Results showed that this protein
fraction just slightly affects bread quality, since no significant changes (P > 0.05) on bread volume and texture were obtained. Only crust and crumb colour were affected in a small amount, and a coarser
crumb structure was also observed when adding 7S protein obtained from germinated soybean at its highest concentration. As
the proportion of protein increased in the flour, both kinds of 7S fraction (germinated and nongerminated) were related to
the increment in water absorption, as well as to the increment in extensographic maximum resistance to extension, specifically
when adding 7S protein obtained from nongerminated soybean seeds. These results showed that the 7S soybean protein, as obtained
in this work, is not related to the reported loaf bread quality improving effect of this legume when it is added in small
quantities. 相似文献
103.
In the imminent future, scarcity of resources will require architects to be as engaged with the redesign of services and infrastructure as they are now with the specifying of new materials. This is a situation that will be made all the more urgent by the increasing gap in public spending at a local and national level. Clare Brass, Flora Bowden and Kate McGeevor describe SEED Foundation, an enterprise that advocates new design approaches for sustainability, and explain how FoodLoop, a food waste and food growing project in London, is helping residents of the Maiden Lane Estate in King's Cross to take over the running of a food waste collection scheme without the aid of council funding. 相似文献
104.
Paride Salvatore Occhipinti Nunziatina Russo Paola Foti Irene Maria Zingale Alessandra Pino Flora Valeria Romeo Cinzia L. Randazzo Cinzia Caggia 《Journal of the science of food and agriculture》2024,104(7):3823-3833
The intensified attention to health, the growth of an elderly population, the changing lifestyles, and the medical discoveries have increased demand for natural and nutrient-rich foods, shaping the popularity of microalgae products. Microalgae thanks to their metabolic versatility represent a promising solution for a ‘green’ economy, exploiting non-arable land, non-potable water, capturing carbon dioxide (CO2) and solar energy. The interest in microalgae is justified by their high content of bioactive molecules, such as amino acids, peptides, proteins, carbohydrates, polysaccharides, polyunsaturated fatty acids (as ω-3 fatty acids), pigments (as β-carotene, astaxanthin, fucoxanthin, phycocyanin, zeaxanthin and lutein), or mineral elements. Such molecules are of interest for human and animal nutrition, cosmetic and biofuel production, for which microalgae are potential renewable sources. Microalgae, also, represent effective biological systems for treating a variety of wastewaters and can be used as a CO2 mitigation approach, helping to combat greenhouse gases and global warming emergencies. Recently a growing interest has focused on extremophilic microalgae species, which are easier to cultivate axenically and represent good candidates for open pond cultivation. In some cases, the cultivation and/or harvesting systems are still immature, but novel techniques appear as promising solutions to overcome such barriers. This review provides an overview on the actual microalgae cultivation systems and the current state of their biotechnological applications to obtain high value compounds or ingredients. Moreover, potential and future research opportunities for environment, human and animal benefits are pointed out. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
105.
Aitana Tamayo Joanna Kyziol-Komosinska MªJesus Sánchez Pio Calejas Juan Rubio MªFlora Barba 《Journal of the European Ceramic Society》2012,32(11):2831-2841
Two natural smectite clays named BC and AC were thermal and chemically treated. Apart from smectite, quartz and kaolinite, BC clay also contains calcite, whereas illite and higher quartz content is found in AC. Treatment at 823 K leads to a collapse of the smectite structure. Treating with H2SO4 or NaOH also leads to the elimination of calcite and Al and Si ions. The higher swelling capacity of BC clay is in accordance with its higher cation exchange capacity. values for both smectites decreases with the applied treatments. The surface acid–base constants determined for BC clay are higher than those obtained for AC independently of the applied treatment. This result together with the higher nanorugosity index, has been attributed to the higher quartz of the AC clay. Moreover, it has been observed that the cationic exchange capacity increases in both clays with the acidity of the surface. 相似文献
106.
In Vitro and In Vivo Inhibition of Intestinal Glucose Transport by Guava (Psidium Guajava) Extracts
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Ulrike Müller Flora Stübl Bettina Schwarzinger Georg Sandner Marcus Iken Markus Himmelsbach Clemens Schwarzinger Nicole Ollinger Verena Stadlbauer Otmar Höglinger Tobias Kühne Peter Lanzerstorfer Julian Weghuber 《Molecular nutrition & food research》2018,62(11)
1 Scope
Known pharmacological activities of guava (Psidium guajava) include modulation of blood glucose levels. However, mechanistic details remain unclear in many cases.2 Methods and results
This study investigated the effects of different guava leaf and fruit extracts on intestinal glucose transport in vitro and on postprandial glucose levels in vivo. Substantial dose‐ and time‐dependent glucose transport inhibition (up to 80%) was observed for both guava fruit and leaf extracts, at conceivable physiological concentrations in Caco‐2 cells. Using sodium‐containing (both glucose transporters, sodium‐dependent glucose transporter 1 [SGLT1] and glucose transporter 2 [GLUT2], are active) and sodium‐free (only GLUT2 is active) conditions, we show that inhibition of GLUT2 was greater than that of SGLT1. Inhibitory properties of guava extracts also remained stable after digestive juice treatment, indicating a good chemical stability of the active substances. Furthermore, we could unequivocally show that guava extracts significantly reduced blood glucose levels (≈fourfold reduction) in a time‐dependent manner in vivo (C57BL/6N mice). Extracts were characterized with respect to their main putative bioactive compounds (polyphenols) using HPLC and LC‐MS.3 Conclusion
The data demonstrated that guava leaf and fruit extracts can potentially contribute to the regulation of blood glucose levels. 相似文献107.
Post-quake urban road network functionality assessment for seismic emergency management in historical centres 总被引:2,自引:0,他引:2
Mariano Angelo Zanini Flora Faleschini Paolo Zampieri Carlo Pellegrino Gregorio Gecchele Massimiliano Gastaldi 《Structure and Infrastructure Engineering》2017,13(9):1117-1129
In this paper, a procedure for the evaluation of the interaction between existing buildings and urban roadway networks after a seismic event is proposed. This question is relevant in historical urban centres, where urbanisation typology has evidenced, in the past, lack of road networks’ residual connectivity in post-earthquake conditions. The present study proposes a method for the evaluation of the residual functionality in urban context, moving from the execution of building surveys, the application of probabilistic concepts and fuzzy logic with the aim to define probable urban road network damage scenarios. The methodology is applied to the Municipality of Conegliano (northeastern Italy) evaluating the potential seismic damage scenario to the historical urban centre and highlighting criticisms in the post-earthquake rescue operations. 相似文献
108.
Screening of the anthocyanin profile and in vitro pancreatic lipase inhibition by anthocyanin‐containing extracts of fruits,vegetables, legumes and cereals
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109.
L Franco L Guida S Bruzzone E Zocchi C Usai A De Flora 《Canadian Metallurgical Quarterly》1998,12(14):1507-1520
CD38 is a type II transmembrane glycoprotein expressed in many vertebrate cells. It is a bifunctional ectoenzyme that catalyzes both the synthesis of Cyclic ADP-ribose (cADPR) from NAD+ and the degradation of cADPR to ADP-ribose by means of its ADP-ribosyl cyclase and cADPR-hydrolase activities, respectively. The cyclase also converts NGD+ to cyclic GDP-ribose (cGDPR), which is refractory to cADPR-hydrolase. cADPR, but not cGDPR, is a potent calcium mobilizer from intracellular stores. It has been demonstrated to be a new second messenger involved in the regulation of calcium homeostasis in many cell types, from plants to mammals. The number of physiological processes shown to be regulated by cADPR is steadily increasing. A topological paradox exists because ectocellularly generated cADPR acts intracellularly. Here we demonstrate that the catalytic functioning of CD38 is accompanied by a cADPR (cGDPR) -transporting activity across natural and artificial membranes. In resealed membranes from CD38(+) human erythrocytes, transport of catalytically generated cADPR or cGDPR was saturation dependent and occurred against a concentration gradient. Likewise, CD38-reconstituted proteoliposomes were active in concentrating NAD+ (NGD+) -derived cADPR (cGDPR) inside the vesicle compartment. Moreover, the cADPR-transporting activity in CD38 proteoliposomes prevented the hydrolase-catalyzed degradation to ADPR that occurs conversely with detergent-solubilized CD38, resulting in selective influx of cADPR. In the CD38 proteoliposomes, catalytically active CD38 exhibited monomeric, dimeric, and tetrameric structures. In CD38 sense- but not in antisense-transfected HeLa cells, externally added NAD+ resulted in significant, transient increases in cytosolic calcium. These data suggest that transmembrane juxtaposition of two or four CD38 monomers can generate a catalytically active channel for selective formation and influx of cADPR (cGDPR) to reach cADPR-responsive intracellular calcium stores. 相似文献
110.
A two-year study evaluated the Michigan checklane motor vehicle inspection system as a trial substitute for a periodic motor vehicle inspection program. Two counties served as test areas. One county had a checklane inspection of 15% of its cars per year; the other county had a simulated periodic motor vehicle inspection. Random checklanes were used in 1975 and 1976 to estimate the condition of the cars in each county, with minimum sample sizes of 2000 cars in each group. The rates of mechanical outages were found to depend strongly on the age of the cars. Cars involved in the simulated PMVI had to have the same owner over a two year period and proved to be a self-selected group. The PMVI vehicles were in somewhat better mechanical condition than the general population even before being subject to the PMVI. After adjusting for this and the age of the vehicle, no significant differences were found in the rates of vehicles passing the inspection, even though the design had a power of at least 90% of detecting a difference of 0.05 in the rate of passing the inspection. Estimates of repair for several components were also developed and are presented. 相似文献