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Alina A. Tomchuk Nadezhda N. Shershakova Sergey M. Andreev Evgeniy A. Turetskiy Oleksandr I. Ivankov Olena A. Kyzyma 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(4):245-249
AbstractSmall-angle X-ray and neutron scattering was applied for the structural characterization of aggregates in water dispersions of fullerene C60 prepared by dialysis method and its conjugate with amino acid arginine. Two compounds are also compared with respect to their toxic properties. Experiments on the cytotoxicity of these systems on the A549, HepG2 and HeLa cells showed no toxic effects of the dispersions. 相似文献
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In the first critical assessment of knowledge economy dynamic paths in Africa and the Middle East, but for a few exceptions, we find overwhelming support for diminishing cross-country disparities in knowledge-based economy dimensions. The paper employs all the four components of the World Bank's Knowledge Economy Index (KEI): economic incentives, innovation, education, and information infrastructure. The main finding suggests that sub-Saharan African (SSA) and the Middle East and North African (MENA) countries with low levels of KE dynamics and catching-up their counterparts of higher KE levels. We provide the speeds of integration and time necessary to achieve full (100%) integration. Policy implications are also discussed. 相似文献
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This article investigates nexuses between innovations in mobile money and financial inclusion. Demand and supply factors that affect the diffusion of mobile services as well as macro-level institutional and economic factors are taken in account. The focus is on 148 countries with data mostly consisting of 2010–2014 averages. The empirical evidence is based on Tobit regressions. The study finds that when the empirical analysis is robust to multicollinearity, two main tendencies are apparent: the significant findings of Lashitew et al. (2019) [1] are confirmed and many new significant estimated coefficients emerge. While this study confirms the findings of the underlying research, it also goes further to improve the harmony in narratives between the predictors and the outcome variables. Accordingly, by accounting for multicollinearity, the earlier findings are now more consistent across the set of predictors (i.e. demand and supply factors) and the attendant financial inclusion outcomes (i.e. mobile money accounts, mobile used to send money and mobile used to receive money). 相似文献
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《Egyptian Journal of Petroleum》2022,31(3):37-45
Corrosion is recognized as a notable problem in oil sector where API5LX60 steel transmission pipelines are in frequent use. In this report, three oxazolone derivatives as potential corrosion inhibitors were investigated on API5LX60 graded carbon steel in 1N H2SO4 solution in stagnant conditions at concentrations 50–200 ppm. Gravimetric weight loss coupons and electrical resistance corrosion monitoring techniques performed on test samples showed inhibitory properties with best at 200 ppm inhibitor concentration. The results further revealed that the degree of inhibition was concentration dependent. Inhibitor I exhibited the highest inhibition efficiency of 90.70% at 200 ppm concentration. Statistical analysis using multiple linear regression model procreated high R2 value of 0.998 and p-value < 0.0001 asserting a smooth linear dependence of inhibitor efficiency on oxazolone concentration and weight loss of the steel. Again, surface analysis affirmed the formation of protective coating of inhibitor on steel surface. Furthermore, the oxazolone inhibitor adsorbed physically on the steel surface and obeyed the Langmuir isotherm which is evident from the linear correlation coefficient value of 0.9992. 相似文献
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针对应用领域中判断水平面及水平面夹角的问题,设计一种倾斜姿态角传感器。把MEMS加速度计SCA103T-D04与C8051F47单片机组合在一起,对MEMS加速度计输出信号进行调理和AD采集,单片机C8051F047完成数据分析和温度补偿,并通过CAN总线通讯接口和RS232通讯接口输出倾斜角度值,输出周期为200 ms。该倾斜姿态角传感器测量精度为0.03°,测量范围为–6°~6°,具有体积小、重量轻、精度高、温度适应范围宽的特性,可广泛应用于建筑、道路、桥梁及军用设备等领域。 相似文献
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Fish inhabiting fecally polluted bodies of water are often used for human consumption. Such fish can be contaminated by enteric human pathogens and may pose a potential risk to public health. Controlled experiments with 132 fish of 100 g average weight were conducted to evaluate the rate of contamination of various tissues of fish (tilapia hybrids). The fish were exposed to E. coli introduced into the ambient water at concentrations of up to 106 cfu/ml. Additional experiments were conducted with diluted wastewater containing Aeromonas, enterococci, fecal coliform and F+ coliphages. In another experiment poliovirus I was also added. The highest bacterial concentrations were recovered from the digestive tract (DT), some 5–24 h following exposure, with DT levels essentially similar to those in the inoculated water. In the E. coli experiments, geometric mean levels of about 102 cfu/cm2 were recovered from the skin, 26 cfu/g in the spleen and 102 cfu/g in the liver. Most of the muscle samples were not contaminated. Greater contamination was not found under conditions of stress such as high organic load, a water temperature of 37°C or low levels of dissolved oxygen. 相似文献
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Trade relationships connect developed and developing countries. The former produces a consumption good, using labor, capital, and an intermediate “natural” good which is produced in the developing countries using labor and natural species. A finite horizon differential game is settled out. The North decides about either the saving rate or the portion of its disposable income to transfer to the South or both variables jointly. The South selects the range of species used in the production of the intermediate “natural” good required in the North’s productive process. This is a measure of biodiversity loss. The aim of the paper is to study how transfers from North to South affect capital growth and biodiversity conservation.
相似文献
Guiomar Martín-Herrán (Corresponding author)Email: Fax: +34-983-423299 |