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Vasilica Alisa Arus Saadia Nousir Radia Sennour Tze Chieh Shiao Ileana Denisa Nistor René Roy Abdelkrim Azzouz 《International Journal of Hydrogen Energy》2018,43(16):7964-7972
The effect of acid activation on bentonite affinity toward carbon dioxide (CO2) and hydrogen (H2) was investigated at ambient conditions. Characterization through X-ray diffraction and fluorescence, thermal gravimetric analysis, nitrogen adsorption-desorption isotherms, Fourier Transform Infrared spectroscopy and differential scanning calorimetry allowed correlating newly induced textural and structural features with adsorptive properties. Optimum acid treatment improved the specific surface area and porosity. The resulting decrease in dehydration temperature indicates decay in hydrophilic character. The affinity improvement towards hydrogen was due to Brønsted acidity suppression and surface basicity attenuation, which are essential requirements for adsorption on aluminosilicates (AS) via weak Lewis Acid-Base interactions, but excessive acid attack was detrimental. Low Si/Al surfaces should be suitable for CO2 capture, while moderately acid-treated clays should be interesting candidates as hydrogen adsorbents. This allows envisaging promising prospects for low-cost AS-based materials intended for selective CO2-free capture and storage of hydrogen without energy and safety constraints. 相似文献
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Nonsteroidal anti-inflammatory drugs are commonly administered parenterally in addition to antimicrobial mastitis therapy to increase the well-being of the diseased animal. As mastitis is usually a localized infection of mammary tissue, we tested the hypothesis that a local administration of nonsteroidal anti-inflammatory drugs through the teat canal could have anti-inflammatory effects on the affected area. We investigated the effects of intramammarily administered ketoprofen (KET) during an LPS-induced immune response on somatic cell count (SCC) and blood–milk barrier integrity. In addition, we investigated the effects of KET on the mRNA abundance of immune factors and their prostaglandin E2 secretion in primary bovine mammary epithelial cells in vitro. Six cows received 0.2 µg of LPS (serotype O26:B6) together with 50 mg of KET into one quarter and LPS only in the opposing quarter. The increase of SCC and of serum albumin (SA) and IgG concentrations and the increase of lactate dehydrogenase (LDH) activity in milk induced by LPS were lower in quarters that received KET in addition. In 3 cows, intramammary KET (50 mg) without additional LPS did not affect SCC, SA, IgG, and LDH in milk. Effects of KET on the immune response of mammary epithelial cells in vitro were investigated in cells from 3 cows challenged with or without LPS (0.2 µg/mL) and with or without additional KET in 2 concentrations (1.25 or 2.5 mg/mL). Ketoprofen reduced the LPS-induced increase of mRNA abundance of tumor necrosis factor α, IL-8, serum amyloid A, and cyclooxygenase-2. The mRNA abundance of cyclooxygenase-1 and prostaglandin E synthase was reduced in cells without LPS challenge by addition of KET at 2.5 mg/mL. Furthermore, the LPS-induced secretion of prostaglandin E2 of mammary epithelial cells into the supernatant could not be detected if KET was added. The results demonstrate that intramammary KET diminishes the increase of SCC and reduces the impairment of the blood–milk barrier (based on SA and LDH in milk), leading to a reduced IgG concentration in milk during LPS-induced mastitis. In mammary epithelial cells, KET limits the expression of several immune factors that are increased during an immune response. In summary, intramammary administration of KET reduces the inflammatory response in the mammary gland. However, it remains unclear whether the inhibited transfer of immune cells and IgG from blood into milk after KET administration would reduce the success of the immune defense in infectious mastitis. 相似文献
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Liliana Marinescu Denisa Ficai Anton Ficai Ovidiu Oprea Adrian Ionut Nicoara Bogdan Stefan Vasile Laura Boanta Alexandru Marin Ecaterina Andronescu Alina-Maria Holban 《International journal of molecular sciences》2022,23(11)
The synthesis of nanoparticles from noble metals has received high attention from researchers due to their unique properties and their wide range of applications. Silver nanoparticles (AgNPs), in particular, show a remarkable inhibitory effect against microorganisms and viruses. Various methods have been developed to obtain AgNPs, however the stability of such nanostructures over time is still challenging. Researchers attempt to obtain particular shapes and sizes in order to tailor AgNPs properties for specific areas, such as biochemistry, biology, agriculture, electronics, medicine, and industry. The aim of this study was to design AgNPs with improved antimicrobial characteristics and stability. Two different wet chemical routes were considered: synthesis being performed (i) reduction method at room temperatures and (ii) solvothermal method at high temperature. Here, we show that the antimicrobial properties of the obtained AgNPs, are influenced by their synthesis route, which impact on the size and shape of the structures. This work analyses and compares the antimicrobial properties of the obtained AgNPs, based on their structure, sizes and morphologies which are influenced, in turn, not only by the type or quantities of precursors used but also by the temperature of the reaction. Generally, AgNPs obtained by solvothermal, at raised temperature, registered better antimicrobial activity as compared to NPs obtained by reduction method at room temperature. 相似文献
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Alina Culetu Anicuta Stoica-Guzun Denisa Eglantina Duta 《International Journal of Food Science & Technology》2021,56(1):126-137
This study investigated the effect of six fats (margarine, butter, lard-LAR, refined palm oil-RPO, refined palm oil with stearin-RPOS, hydrogenated palm oil-HPO) with different solid fat content (SFC) on gluten-free oat dough and cookie properties. RPOS and HPO had the highest SFC. RPO dough was the softest, whereas HPO was the hardest one. Dough hardness was correlated with SFC (r = 0.87). Dough stickiness was positively correlated with dough hardness (r = 0.92). Dough hardness influenced the breaking force of the cookies (r = 0.79). HPO were the hardest cookies. Oscillatory test revealed that HPO dough was the stiffest as well as presented a higher rigidity compared to the other samples as showed by the creep tests. LAR cookies were the darkest, while HPO were the lightest. SFC of fats is the most important composition parameter which influences thermal, textural and rheological properties of the oat dough. 相似文献
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Anton Ficai Ecaterina Andronescu Georgeta Voicu Cristina Ghitulica Denisa Ficai 《Materials Characterization》2010,61(4):402-407
The purpose of this investigation is to study the influence of collagenous supports and ionic species on the precipitation of hydroxyapatite (HA) from aqueous solutions. To this end, we obtained hydroxyapatite by co-precipitation from a solution of calcium hydroxide and sodium dihydrogenophosphate. The formation of HA was studied by energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The results of this study indicate that the morphology of hydroxyapatite is highly influenced by the support material and the ionic species present. The obtained materials were studied by scanning electron microscopy (SEM). 相似文献
16.
Development of a set of simple bacterial biosensors for quantitative and rapid measurements of arsenite and arsenate in potable water 总被引:1,自引:0,他引:1
Stocker J Balluch D Gsell M Harms H Feliciano J Daunert S Malik KA van der Meer JR 《Environmental science & technology》2003,37(20):4743-4750
Testing for arsenic pollution is commonly performed with chemical test kits of unsatisfying accuracy. Bacterial biosensors are an interesting alternative as they are easily produced, simple, and highly accurate devices. Here, we describe the development of a set of bacterial biosensors based on a nonpathogenic laboratory strain of Escherichia coli, the natural resistance mechanism of E. coli against arsenite and arsenate, and three reporter proteins: bacterial luciferase, beta-galactosidase and Green Fluorescent Protein (GFP). The biosensors were genetically optimized to reduce background expression in the absence of arsenic. In calibration experiments with the biosensors and arsenite-amended potable water, arsenite concentrations at 4 microg of As/L (0.05 microM) were routinely and accurately measured. The currently most quantitative system expressed the bacterial luciferase as reporter protein, responding proportional with a concentration range between 8 and 80 microg of As/L. Sensor cells could be stored as frozen batches, resuspended in plain media, and exposed to the aqueous test sample, and light emission was measured after 30-min incubation. Field testing for arsenite was achieved with a system that contained beta-galactosidase, producing a visible blue color at arsenite concentrations above 8 microg/L. For this sensor, a protocol was developed in which the sensor cells were dried on a paper strip and placed in the aqueous test solution for 30 min after which time color development was allowed to take place. The GFP sensor showed good potential for continuous rather than end point measurements. In all cases, growth of the biosensors and production of the strip test was achieved by very simple means with common growth media, and quality control of the sensors was performed by isolating the respective plasmids with the genetic constructs according to simple standard genetic technologies. Therefore, the biosensor cells and protocols may offer a realistic alternative for measuring arsenic contamination in potable water. 相似文献
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Gabriela Petrisor Ludmila Motelica Luminita Narcisa Craciun Ovidiu Cristian Oprea Denisa Ficai Anton Ficai 《International journal of molecular sciences》2022,23(7)
Melissa officinalis is a medicinal plant rich in biologically active compounds which is used worldwide for its therapeutic effects. Chemical studies on its composition have shown that it contains mainly flavonoids, terpenoids, phenolic acids, tannins, and essential oil. The main active constituents of Melissa officinalis are volatile compounds (geranial, neral, citronellal and geraniol), triterpenes (ursolic acid and oleanolic acid), phenolic acids (rosmarinic acid, caffeic acid and chlorogenic acid), and flavonoids (quercetin, rhamnocitrin, and luteolin). According to the biological studies, the essential oil and extracts of Melissa officinalis have active compounds that determine many pharmacological effects with potential medical uses. A new field of research has led to the development of controlled release systems with active substances from plants. Therefore, the essential oil or extract of Melissa officinalis has become a major target to be incorporated into various controlled release systems which allow a sustained delivery. 相似文献
18.
In 2 picture-naming and 2 grammaticality judgment experiments, the authors explored how the phonological form of a word, especially its termination, affects gender processing by monolinguals and unbalanced bilinguals speaking German. The results of the 2 experiments with native German speakers yielded no significant differences: The reaction times were statistically identical for items from gender typical, ambiguous, and gender atypical groups. The 2 experiments with English bilinguals who had learned German as a second language (L2), however, provided evidence that the L2 word's termination plays a role in L2 gender processing. Participants were fastest when producing gender-marked noun phrases containing a noun with a gender typical termination and slowest when the noun had a gender atypical termination. Analogous results were obtained in the grammaticality judgment experiment. These findings support the assumption that there is interaction between the levels of phonological encoding and grammatical encoding at least in bilingual processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Maria Snmez Mihai Georgescu Mihaela Vlsan Marius Radulescu Denisa Ficai Georgeta Voicu Anton Ficai Laurentia Alexandrescu 《应用聚合物科学杂志》2015,132(26)
In this article, polymer composites based on polypropylene (PP) matrix reinforced with short glass fibers type E (GF‐type E) were obtained. However, to ensure good interfacial adhesion and stress transfer across the interface, the influence of the chemical functionalization of the phases was analyzed. The better interfacial adhesion is assured by the use of maleic anhydride grafted PP and amino‐functionalized GF. The obtained composite materials were tested from the point of view of composition, morphology, and mechanical properties. It can conclude that the chemical functionalization of the two phases is beneficial from the point of view of compatibility of the phases and consequently higher mechanical properties are obtained. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42163. 相似文献
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