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121.
This paper presents the ability of electrostatic sprayed tin oxide (SnO2) and tin oxide doped with copper oxide (1, 2, and 4 at.% Cu) films to detect different pollutant gases, i.e., H2S, SO2, and NO2. The influence of a copper oxide dopant on the SnO2 morphology is studied using scanning electron microscopy (SEM) technique, which reveals a small decrease in the porosity and particle size when the amount of dopant is increased. The sensing properties of the SnO2 films are greatly improved by doping, i.e., the Cu-doped SnO2 films have large response to low concentration (10 ppm) of H2S at low operating temperature (100 °C). Furthermore, no cross-sensitivity to 1 ppm NO2 and 20 ppm SO2 is observed. Among the studied films, the 1 at.% Cu-doped SnO2 layer is the most sensitive in the detection of all the studied gases. 相似文献
122.
Beatrice-Cristina Ivan Stefania-Felicia Barbuceanu Camelia Mia Hotnog Adriana Iuliana Anghel Robert Viorel Ancuceanu Mirela Antonela Mihaila Lorelei Irina Brasoveanu Sergiu Shova Constantin Draghici Octavian Tudorel Olaru George Mihai Nitulescu Mihaela Dinu Florea Dumitrascu 《International journal of molecular sciences》2022,23(16)
The current study describes the synthesis, physicochemical characterization and cytotoxicity evaluation of a new series of pyrrole derivatives in order to identify new bioactive molecules. The new pyrroles were obtained by reaction of benzimidazolium bromide derivatives with asymmetrical acetylenes in 1,2-epoxybutane under reflux through the Huisgen [3 + 2] cycloaddition of several ylide intermediates to the corresponding dipolarophiles. The intermediates salts were obtained from corresponding benzimidazole with bromoacetonitrile. The structures of the newly synthesized compounds were confirmed by elemental analysis, spectral techniques (i.e., IR, 1H-NMR and 13C-NMR) and single-crystal X-ray analysis. The cytotoxicity of the synthesized compounds was evaluated on plant cells (i.e., Triticum aestivum L.) and animal cells using aquatic crustaceans (i.e., Artemia franciscana Kellogg and Daphnia magna Straus). The potential antitumor activity of several of the pyrrole derivatives was studied by performing in vitro cytotoxicity assays on human adenocarcinoma-derived cell lines (i.e., LoVo (colon), MCF-7 (breast), and SK-OV-3 (ovary)) and normal human umbilical vein endothelial cells (HUVECs). The obtained results of the cytotoxicity assessment indicated that the tested compounds had nontoxic activity on Triticum aestivum L., while on Artemia franciscana Kellogg nauplii, only compounds 2c and 4c had moderate toxicity. On Daphnia magna, 4b and 4c showed high toxicity; 2a, 2b, and 2c moderate to high toxicity; only 4a and 4d were nontoxic. The compound-mediated cytotoxicity assays showed that several pyrrole compounds demonstrated dose- and time-dependent cytotoxic activity against all tested tumor cell lines, the highest antitumor properties being achieved by 4a and its homologue 4d, especially against LoVo colon cells. 相似文献
123.
Anca Peter Leonard Mihaly Cozmuta Camelia Nicula Anca Mihaly Cozmuta Goran Drazic Antonio Peñas Franks Kamgang Nzekoue Xiaohui Huang Gianni Sagratini Stefania Silvi 《Packaging Technology and Science》2023,36(2):97-110
Chicken meat is well known for its high nutritional value. Its shelf life is short, due to the pronounced perishability, even under refrigeration. Paper bags are usually used as packaging materials, due to their biodegradability. The main negative aspect concerning paper is its high porosity and low moisture barrier. In this regard, it has to be coated/modified with efficient moisture barrier materials. The storage of chicken breast meat wrapped in four types of paper-based materials currently in use in Romania (RO), Italy (IT), Spain (SP) and Slovenia (SLO) is reported. RO and IT are paper coated with polyethylene (PE) film, SP is waxed paper, and SLO is paper modified with hydrophobized starch. The influence of the coating film on the organoleptical, biochemical and microbiological characteristics of the chicken breast meat stored at 4°C was the aim of the study. The mathematical modelling revealed two aspects: (1) the stability period in which the meat safe for consumption is in the range 1.92–2.18 days in the case of all paper types, and (2) cadaverine, the amine generated by protein degradation, is a less sensitive indicator of the meat alteration than microbial growth. The papers coated with PE (RO and IT samples) and with hydrophobized starch (SLO paper) were packaging materials more efficient that the waxed paper (SP sample). The polyethylene film reduced the conversion of putrescine into spermidine in a higher extent than wax. 相似文献