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41.
Sangeetha Jayakumar T. Nandakumar M. Vadivel C. Thinaharan Rani P. George 《Journal of Adhesion Science and Technology》2020,34(7):713-743
AbstractWe report, here, the corrosion inhibition of mild steel specimen in 1?M HCl by tamarind fruit pulp aqueous (TFPA) extract. The inhibition property in the presence of TFPA extract is studied using weight loss, polarization measurement and electrochemical impedance spectroscopy (EIS). The inhibitor efficiency is found to vary from 74% to 88% (weight loss method) with TFPA concentration of 100–600?ppm. The reduction in Tafel slopes shows that TFPA acts as a mixed-type inhibitor. The adsorption of the inhibitor on the metal surface follows Langmuir isotherm. The standard Gibbs free energy of adsorption value of –40?kJ/mol suggests the chemisorption of inhibitor molecules via coordinate bond. AFM results exhibit a decrease in the surface roughness of mild steel, exposed to 1?M HCl from 299?±?12 to 154?±?6.6?nm, with increasing concentration of inhibitor from 0 to 600?ppm due to the uniform coverage of inhibitor molecules on the metal surface. X-ray photoelectron spectroscopy de-convoluted high resolution profiles of C 1?s (carbon) for mild steel exposed to 1?M HCl with 600?ppm inhibitor show major peaks corresponding to sp3 C–C/C–H (284.9?eV) and oxygen bondings in C–OH, C=O, COOH with a binding energy of 285.9, 286.9, 288.5?eV, respectively, thereby confirming the adsorption of organic moieties on mild steel surface. Fourier transform infrared spectroscopy further confirms the adsorption of inhibitor molecules on the metal surface. Therefore, tamarind fruit pulp extract is a potential corrosion inhibitor for mild steel, which is cost-effective, green and non-toxic. 相似文献
42.
主动声呐信号处理中一般采用匹配滤波和背景均衡等算法检测回波信号,为提高信号的检测性能,还需利用信号与混响和环境噪声在时间、空间上的统计特征差异。文章在对信号的时、空特征算法进行简单描述的基础上,提出了频率能量统计特征和方位能量统计特征,将两种特征检测器的输出进行融合处理构成时、空联合检测器。仿真和试验数据处理结果证明,此方法可有效提高机动小目标在混响及环境噪声中的检测性能。 相似文献
43.
CFTR氯离子通道是目前国际上新兴的治疗分泌型腹泻的分子药靶,CFTR抑制剂通过阻断离子通道的过度分泌来治疗腹泻症状。由于其抑制剂极为稀少,因此CFTR抑制剂的筛选工作是相关领域中最基础、最关键的环节。天然产物兼具结构和生物活性的多样性,在新药和先导化合物的发现中起着重要作用,是药物开发的主要来源,而食品药品来源的天然产物更因为对人体安全无毒副作用而倍受青睐。食品药品来源的CFTR氯离子通道抑制剂对于CFTR相关的腹泻等疾病的机理研究和治疗具有重要价值,同时也为天然产物资源用于现代药物发现提供了依据。 相似文献
44.
Flood hazard mapping is a topic of increasing interest involving several aspects in which a series of progress steps have occurred in recent years. Among these, a valuable advance has been performed in solving 2-D shallow water equations in complex topographies and in the use of high resolution topographic data. However, reliable predictions of flood-prone areas are not simply related to these two important aspects. A key element is the accurate set up of the river model. This is primarily related to the representation of the topography but also requires particular attention to the insertion of man-made structures and hydrological data within the computational domain. There is the need to use procedures able to 1) obtain a reliable computational domain, characterized by a total number of elements feasible for a common computing machine, starting from the huge amount of data provided by a LIDAR survey, 2) deal with river reach that receives significant lateral inflows, 3) insert bridges, buildings, weirs and all the structures that can interact with the flow dynamics. All these issues have large effects on the modelled water levels and flow velocities but there are very few papers in the literature on these topics in the framework of the 2-D modelling. So, in this work, attention is focused on the techniques to deal with the above-mentioned issues, showing their importance in flood mapping using two actual case studies in Southern Italy. In particular, the simulations showed in this paper highlight the presence of backwater effects, sudden and numerous changes in the flow regime, induced by the detailed river model, that underline the importance of using 2-D fully dynamic unsteady flow equations for flood mapping. 相似文献
45.
《International Journal of Hydrogen Energy》2020,45(30):15358-15365
Among the different coatings developed for proton exchange membrane fuel cell steel bipolar plate, nitride-based coatings present several advantages compared to gold or polymeric coating: high chemical stability, low interfacial contact resistance and reasonable cost. In this work, 50 nm thick chromium nitride coatings are deposited by reactive magnetron sputtering on 316L stainless steel foil. They are optimized to fulfill the Department of Energy targets in terms of interfacial contact resistance (ICR) and corrosion resistance, with values of 8.4 mΩ cm−2 (at 100 N cm−2) and 0.10 μA cm−2 (in 0.6 M H2SO4 solution at 0.48 Vvs. SCE potential) respectively. Moreover, they retain their excellent properties after high deformation (biaxial deformation of 20% in x-axis and 5% in y-axis), giving the possibility to achieve, in line, the stamping of a bipolar plate from a coated foil. The etching of the substrate, prior to the coating deposition, appears to be determinant to obtain low and stable corrosion current and ICR. The removing of interfacial oxyde leads to better coating adhesion and improves the corrosion resistance and electrical conductivity. The enhancement of the properties (low ICR and high corrosion resistance) is durable, with no signicant change of the ICR value up to 200 days after deposition. 相似文献
46.
《International Journal of Hydrogen Energy》2020,45(1):401-411
Cupric chloride is used as oxidant to synthesize polypyrrole doped with inorganic mineral (ImDPpy). The formation of ImDPpy was confirmed by 1HNMR, BET, SEM, HRTEM, DSC, FTIR, Raman, XRD, UV–vis and XPS studies. The surface area calculated for ImDPpy is 36.671 m2/g. Surface area of IMDPpy is 4.671 m2/g higher than the reported value of Ppy in the literature. In DSC, ImDPpy display a peak at 88.07 °C (endothermic glass transition temperature, Tg), Tg of ImDPpy is almost identical to that of Ppy-MWCNT composite and is higher than Tg of undoped Ppy. Electrochemical analysis of ImDPpy in 0.01 M NaOH indicated the maximum charge stored in ImDPpy in the form of protons as 8090 mF/g. The maximum hydrogen storage capacity of ImDPpy is found to be 18mAh/g at an applied current density of 1 mA/cm2. The mineral doped in Ppy during polymerization is identified as [Cu2(OH)3Cl] from XPS and Raman analysis. 相似文献
47.
48.
JONG HWAN SUNG 《Biocell》2022,46(5):1177-1180
Organ-on-a-chip technology aims to reproduce the key physiological features of human organs and tissues, even complex actions of multi-organ interaction. While organ-on-a-chips at single-organ level has made notable achievement during the last decade, multi-organ-on-a-chips, which manifests unique advantages, has started gathering attention only recently. In this viewpoint, we discuss the current status of organ-on-a-chip technology, with a specific emphasis on multi-organ-on-a-chip. Key technological advances contributing to the maturation of the field, and challenges that need to be addressed before wider adoption in relevant fields are discussed. We will share our perspectives on how the multi-organ-on-a-chip can improve the drug development process. 相似文献
49.
FRANCESCO PADUANO EMANUELA ALTOMARE BENEDETTA MARRELLI VINCENZO DATTILO HAIZAL MOHD HUSSAINI PAUL ROY COOPER MARCO TATULLO 《Biocell》2022,46(8):1827-1835
Oral Cancer (OC) is one of the most recurrent cancers in the head and neck squamous cancer (SCCHN)
category. Recently, the genome-wide association studies (GWAS) have gained growing interest in the scientific
community. GWAS have identified several pathways involved in the interactions among general risk factors and
genomic variants affecting SCCHN. This systematic overview aims to critically evaluate the latest data reported within
the scientific literature. The aim was to investigate the impact of genetic aspects on SCCHN onset and prognosis,
involving other clinical and systemic co-factors. PubMed, Google Scholar, and Cancer Genetics Web databases have
been systematically investigated for original articles published in the last two years, reporting studies on the main
queries addressed in this work. This review also comparatively describes the impact of environmental and
pathological co-factors in different types of cancers, clarifying and updating the role of genetic factors in SCCHN
onset and development. The main outcomes reported may be helpful to drive clinicians towards their clinical
evaluations for the most appropriate therapeutic approach in SCCHN. 相似文献
50.
We investigated the diversity and composition of microflora in feces of Lycopus lucidus Turcz.-fed mice. In
addition, we evaluated the production of major cytokines (Interleukin-6 and -10) which are related to inflammation
and fatty acid composition of several tissues. 16S ribosomal DNA sequencing-based microbiome taxonomic profiling
analysis was performed utilizing the EzBioCloud data base. Male mice fed on L. lucidus showed a significantly
reduced number of lactic acid bacteria and coliform in the feces compared with the control group (p < 0.05). 16S
rDNA sequencing analysis of fecal samples showed that L. lucidus supplementation decreased the community of
harmful microflora (Enterobacteriaceae including Escherichia coli and Bacteroides sp.) in feces compared with the
control group (p < 0.05). There were no significant differences in mRNA expression of cytokine IL-6 and IL-10
between the control and L. lucidus fed groups. The fecal fatty acid composition in the L. lucidus group had
percentages of 4:0, 6:0, 8:0 and 10:0 in the intestine but those short chain fatty acids were not detected in the control
group. Our results showed that L. lucidus supplementation influenced gut environment by decreasing harmful
microflora and increased the percentages of several short fatty acids. 相似文献