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41.
Various organosilane-treated SiO2 nanoparticles were dispersed in a 2-pack polyurethane coating. The influence of surface modification and silica content on the electrochemical behaviour of the resultant nanocoatings was investigated. Electrochemical impedance spectroscopy (EIS) and open circuit potential (OCP) variations were examined. The surface chemistry of nanoparticles and its effect on the resultant nanocoating morphology were also studied utilising FTIR, and TEM analyses. The results reveal that the presence of more hydrophobic groups and longer-lengthed hydrophobic chains on the surface of nanoparticles, greatly improves the interfacial interactions at the polymer/filler interfaces resulting in a better corrosion performance.  相似文献   
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Sinarundinaria alpina is a species of mountain bamboo which is a source of various conflicts between the managers of the Kahuzi-Biega National Park (KBNP) and surrounding communities. This mountainous species is threatened by these communities to meet their need for various uses. Six permanent plots of 3 hectares were set between 2000–3000 metres above sea level and floristic inventories were made. In addition, information related to anthropogenic threats related to bamboo exploitation was recorded. All data were analysed using quantitative statistical parameters. Results suggest the existence of 196 species in these six permanent plots of the group Bamboo. The position of this Sinarundinaria alpina vegetation in the dynamic rainforest recovery dynamics is confirmed by the presence of trees and tree-nurseries of these trees. Fifty-three species, 27% of the plants observed, including Sinarundinaria alpina seedlings, contribute to the daily feeding of great apes, mainly Grauer’s Gorilla (Gorilla beringei graueri). This forest appears to be one of their critical habitats. The decrease in the area covered by bamboos is due primarily to anthropogenic activities but also some natural hazards (expansion of Sericostachys scandens, natural fading of Bamboo and attacks by beetles). Following these findings, conservation strategies were proposed. Several strengths were noted, including multiplication of bamboo nurseries and distribution of seedlings to local communities. This can be seen as a strong development of this sector in the future. This study is a preliminary assessment for further investigation.  相似文献   
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International Journal of Coal Science & Technology - The modeling of hydrocarbon selectivity and CO conversion of the Fischer–Tropsch synthesis over Fe–Ni/Al2O3 catalyst by using...  相似文献   
46.
Rice crops are often subject to multiple abiotic stresses simultaneously in both natural and cultivated environments, resulting in yield reductions beyond those expected from single stress. We report physiological changes after a 4 day exposure to combined drought, salt and extreme temperature treatments, following a 2 day salinity pre-treatment in two rice genotypes—Nipponbare (a paddy rice) and IAC1131 (an upland landrace). Stomata closed after two days of combined stresses, causing intercellular CO2 concentrations and assimilation rates to diminish rapidly. Abscisic acid (ABA) levels increased at least five-fold but did not differ significantly between the genotypes. Tandem Mass Tag isotopic labelling quantitative proteomics revealed 6215 reproducibly identified proteins in mature leaves across the two genotypes and three time points (0, 2 and 4 days of stress). Of these, 987 were differentially expressed due to stress (cf. control plants), including 41 proteins that changed significantly in abundance in all stressed plants. Heat shock proteins, late embryogenesis abundant proteins and photosynthesis-related proteins were consistently responsive to stress in both Nipponbare and IAC1131. Remarkably, even after 2 days of stress there were almost six times fewer proteins differentially expressed in IAC1131 than Nipponbare. This contrast in the translational response to multiple stresses is consistent with the known tolerance of IAC1131 to dryland conditions.  相似文献   
47.
A novel coronavirus of zoonotic origin(SARSCoV-2)has recently been recognized in patients with acute respiratory disease.COVID-19 causative agent is structurally and genetically similar to SARS and bat SARS-like coronaviruses.The drastic increase in the number of coronavirus and its genome sequence have given us an unprecedented opportunity to perform bioinformatics and genomics analysis on this class of viruses.Clinical tests like PCR and ELISA for rapid detection of this virus are urgently needed for early identification of infected patients.However,these techniques are expensive and not readily available for point-of-care(POC)applications.Currently,lack of any rapid,available,and reliable POC detection method gives rise to the progression of COVID-19 as a horrible global problem.To solve the negative features of clinical investigation,we provide a brief introduction of the general features of coronaviruses and describe various amplification assays,sensing,biosensing,immunosensing,and aptasensing for the determination of various groups of coronaviruses applied as a template for the detection of SARS-CoV-2.All sensing and biosensing techniques developed for the determination of various classes of coronaviruses are useful to recognize the newly immerged coronavirus,i.e.,SARS-CoV-2.Also,the introduction of sensing and biosensing methods sheds light on the way of designing a proper screening system to detect the virus at the early stage of infection to tranquilize the speed and vastity of spreading.Among other approaches investigated among molecular approaches and PCR or recognition of viral diseases,LAMP-based methods and LFAs are of great importance for their numerous benefits,which can be helpful to design a universal platform for detection of future emerging pathogenic viruses.  相似文献   
48.
Shabani  Mohsen Ostad  Baghani  Amir  Khorram  Ali  Heydari  Fatemeh 《SILICON》2020,12(12):2977-2987
Silicon - Magnetic stirring is considered to be the most useful stirring method in semi-solid casting processes which doesn’t have the restrictions of the mechanical stirring. In this...  相似文献   
49.
Esmaeili  Akbar  Pourkhodabakhshi  Fatemeh 《SILICON》2020,12(3):521-534
Silicon - Metformin (MF) and L. albuman are used to treat type 2 diabetes. Diabetes causes problems such as blindness and albumin excretion. In this study, metformin, L. albuman and a composition...  相似文献   
50.
Shariati  Fatemeh  Poordeljoo  Tahereh  Zanjanchi  Pegah 《SILICON》2020,12(12):2941-2946
Silicon - SiO2 nano-particles are applied in different industries such as ceramic producing, glass making, cosmetic products, medicines, magnetic mixtures, heat and electric insulators and glazing...  相似文献   
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