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81.
Ihebrodike M. Mejeha Michael C. Nwandu Kelechukwu B. Okeoma Lebe A. Nnanna Maduabuchi A. Chidiebere Francis C. Eze Emeka E. Oguzie 《Journal of Materials Science》2012,47(6):2559-2572
The adsorption of Aspilia africana extract and subsequent corrosion inhibition of aluminium alloy AA3003 in hydrochloric acid solutions have been investigated
using gravimetric and electrochemical techniques. Inhibition efficiency increased with extract concentration and temperature
rise. Polarization studies revealed that the extract essentially inhibited the cathodic reaction. An adsorption mechanism
involving physisorption and chemisorption of extract constituents at low and high temperatures, respectively, has been proposed
from the trend of adsorption-free energies. Quantum chemical computations and molecular dynamics simulations described the
individual contributions of some extract constituents to the observed inhibiting effect. 相似文献
82.
Francis T. S. Yu 《Optical Memory & Neural Networks》2017,26(2):150-156
Gravitation is one of the most intriguing forces in space that govern all the interstellar spectacles motion in this universe. In this article we have shown there is a profound relationship between gravitational fields with respect to its converted energy. Since time is an inevitable element in every aspect of science; we have developed a partial differential equation from Einstein’s energy equation in which we show that gravitational field can be coupling with its diverging energy radiation. We have also shown that energy to mass conversion in principle is conceivable by means of energy convergent operation (i.e., in-flow) into a unit space. In fact this could have been happen by the eventuality of a black hole explosion, as remains to be observed. 相似文献
83.
James Eberwine Ditte Lovatt Peter Buckley Hannah Dueck Chantal Francis Tae Kyung Kim Jaehee Lee Miler Lee Kevin Miyashiro Jacqueline Morris Tiina Peritz Terri Schochet Jennifer Spaethling Jai-Yoon Sul Junhyong Kim 《Journal of the Royal Society Interface》2012,9(77):3165-3183
The building blocks of complex biological systems are single cells. Fundamental insights gained from single-cell analysis promise to provide the framework for understanding normal biological systems development as well as the limits on systems/cellular ability to respond to disease. The interplay of cells to create functional systems is not well understood. Until recently, the study of single cells has concentrated primarily on morphological and physiological characterization. With the application of new highly sensitive molecular and genomic technologies, the quantitative biochemistry of single cells is now accessible. 相似文献
84.
This study presents a methodology for making bricks, in a cost-effective and environmentally friendly manner, using the tailings produced from iron ore mines in Western Australia (WA). The study was based on the geopolymerisation process, which is known to conserve energy by reducing the emission of greenhouse gases. The reduction is accomplished by avoiding the processes of high temperature kiln firing, traditionally utilised when making bricks from sandy soils with high clay content. In this study, the sodium silicate was added to the mine tailings in powder form, as an activator for the formulation of the geopolymer bricks. The effects of the initial setting time, curing temperature, curing time and activator content on the unconfined compressive strength (UCS), water absorption and other durability properties of the bricks were investigated. X-ray diffraction analysis was performed to investigate the phase composition of the geopolymer bricks. The bricks achieved an UCS as high as 50.53 MPa for the optimum values of the parameters. Technically, the geopolymer bricks that were produced met both the American Society of Testing and Materials and the Australian Standards (AS) requirements for bricks. A cost analysis of the geopolymer bricks is also presented, and this shows that the cost of geopolymer bricks is lower than that of the commercial, fired clay bricks. 相似文献
85.
Hao-Wu Lin Hao-Wei Kang Zheng-Yu Huang Chang-Wen Chen Yi-Hong Chen Li-Yen Lin Francis Lin Ken-Tsung Wong 《Organic Electronics》2012,13(10):1925-1929
Novel organic/ultrathin low work function metal bilayer cathode buffers for small molecule organic solar cells are proposed. Ultrathin low work function metal layers possess a high built-in electric field for effective carrier extraction and a high cathode reflectivity for maximum absorption in the photoactive layers. This leads to a significant increase of short circuit current density and fill factor of cells. By integrating this bilayer cathode buffer with DTDCTB:C60 small molecular heterojunction, the device exhibits a high power conversion efficiency of up to 5.28%, which is an improvement of 22% compared to a device with a traditional single organic layer buffer. 相似文献
86.
87.
Jacky Lu Kathryn P. Haley Jamisha D. Francis Miriam A. Guevara Ryan S. Doster Kelly M. Craft Rebecca E. Moore Schuyler A. Chambers Alberto G. Delgado Maria Blanca Piazuelo Steven M. Damo Dr. Steven D. Townsend Dr. Jennifer A. Gaddy 《Chembiochem : a European journal of chemical biology》2021,22(18):2783-2790
Chronic infection with Helicobacter pylori increases risk of gastric diseases including gastric cancer. Despite development of a robust immune response, H. pylori persists in the gastric niche. Progression of gastric inflammation to serious disease outcomes is associated with infection with H. pylori strains which encode the cag Type IV Secretion System (cag T4SS). The cag T4SS is responsible for translocating the oncogenic protein CagA into host cells and inducing pro-inflammatory and carcinogenic signaling cascades. Our previous work demonstrated that nutrient iron modulates the activity of the T4SS and biogenesis of T4SS pili. In response to H. pylori infection, the host produces a variety of antimicrobial molecules, including the iron-binding glycoprotein, lactoferrin. Our work shows that apo-lactoferrin exerts antimicrobial activity against H. pylori under iron-limited conditions, while holo-lactoferrin enhances bacterial growth. Culturing H. pylori in the presence of holo-lactoferrin prior to co-culture with gastric epithelial cells, results in repression of the cag T4SS activity. Concomitantly, a decrease in biogenesis of cag T4SS pili at the host-pathogen interface was observed under these culture conditions by high-resolution electron microscopy analyses. Taken together, these results indicate that acquisition of alternate sources of nutrient iron plays a role in regulating the pro-inflammatory activity of a bacterial secretion system and present novel therapeutic targets for the treatment of H. pylori-related disease. 相似文献
88.
Belmonte Beatriz A. Aviso Kathleen B. Benjamin Michael Francis D. Tan Raymond R. 《Clean Technologies and Environmental Policy》2022,24(1):289-301
Clean Technologies and Environmental Policy - Biochar application and enhanced weathering are negative emission technologies (NETs) with the potential for large-scale deployment for the removal of... 相似文献
89.
Francis Njoka Shinichi Ookawara Mahmoud Ahmed 《International Journal of Hydrogen Energy》2018,43(3):1285-1302
Solar-driven photoelectrochemical water splitting technology is a promising avenue for a sustainable hydrogen production. In this work, a comprehensive 2-dimensional model is developed and numerically simulated with hematite (α-Fe2O3) as the principal photoelectrode. The model evaluates light absorption, charge transport and electrochemical reactions to elucidate the effects of light transmitting materials, electrolyte height and electrolyte velocity on hydrogen and oxygen gas production. Results indicated that major losses in photocurrents are attributed to the transparent conducting oxide while losses due to the electrolyte increase with its height. Gas concentrations increase with increasing photocurrent densities and also in the direction of the flow. Gas bubbles however decrease with increasing electrolyte velocity. From these results, light reception in the reactor is uneven and poses a bigger challenge due to the bias in gas bubble distribution. Prospects of upscaling tandem schemes hence not only lie in the semiconductor material combinations but rather in the proper integration of system components and operating conditions. 相似文献
90.
Guo Liang Goh Jiaheng Ma Kwee Lim Francis Chua Agarwala Shweta Yue Ping Zhang 《Virtual and Physical Prototyping》2016,11(4):289-294
This research focuses on exploring low-cost and rapid production solutions for fabricating emitters for patch antennas for wireless communication applications. Additive manufacturing technique is employed to fabricate two patch antennas using silver nanoparticle ink on FR4 substrate. Finite-element simulation software, HFSS is used to analyse and predict the theoretical performance of the antenna designs for 2.4?GHz MIMO and 6?GHz wireless data transmission. The fabricated antennas have resonant frequencies closely matching the design values. The work provides a viable solution for fabricating emitters and finally antennas commercially using inkjet printing platform, thus overall reducing the cost and simplifying the process. 相似文献