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排序方式: 共有538条查询结果,搜索用时 15 毫秒
51.
Water is a basic necessity of man. Economical and efficient production or recycling of water is very much needed in today's world. Solar still has emerged as a life-saving technology to distil brackish water and produce drinkable water using solar energy. The aim of this project was to improve the performance of solar still by adding an air blower which creates a bubbling effect in the still due to which the evaporation rate increases. The bubbling effect using the blower makes the raw water to circulate and to distribute heat energy equally. The evaporated raw water was collected in the glass plate as drop particles. The drop condenses due to ambient air and finally distillate output is collected in the jar, which is placed outside the still. The solar still with air blower arrangement gave higher difference in efficiency and higher distilled output when compared with solar still without an air blower. 相似文献
52.
Van Driessche B Tafforeau L Hentges P Carr AM Vandenhaute J 《Yeast (Chichester, England)》2005,22(13):1061-1068
The one-step PCR-mediated technique used for modification of chromosomal loci is a powerful tool for functional analysis in yeast. Both Saccharomyces cerevisiae and Schizosaccharomyces pombe are amenable to this technique. However, the scarce availability of selectable markers for Sz. pombe hampers the easy use of this technique in this species. Here, we describe the construction of new vectors deriving from the pFA6a family, which are suitable for tagging in both yeasts owing to the presence of a nourseothricin-resistance cassette. These plasmids allow various gene manipulations at chromosomal loci, viz. N- and C-terminal tagging with 3HA (haemagglutinin) or 13Myc epitopes, GST (glutathione S-transferase), 4TAP (tandem affinity purification) and several GFP (green fluorescent protein) isoforms. For N-terminal modifications, the use of different promoters allows constitutive (PADH1) or regulatable (PGAL1) promoters for S. cerevisiae and derivatives of Pnmt1 for Sz. pombe expression. 相似文献
53.
Cameron P. Brown Jennifer L. Boyd Antony J. Palmer Mick Phillips Charles‐Andre Couture Maxime Rivard Philippa A. Hulley Andrew J. Price Andreas Ruediger Francois Légaré Andrew J. Carr 《Advanced functional materials》2016,26(42):7662-7667
Piezoelectricity is a well‐established property of biological materials, yet its functional role has remained unclear. Here, a mechanical effect of piezoelectric domains resulting from collagen fibril organisation is demonstrated, and its role in tissue function and application to material design is described. Using a combination of scanning probe and nonlinear optical microscopy, a hierarchical structuring of piezoelectric domains in collagen‐rich tissues is observed, and their mechanical effects are explored in silico. Local electrostatic attraction and repulsion due to shear piezoelectricity in these domains modulate fibril interactions from the tens of nanometre (single fibril interactions) to the tens of micron (fibre interactions) level, analogous to modulated friction effects. The manipulation of domain size and organisation thus provides a capacity to tune energy storage, dissipation, stiffness, and damage resistance. 相似文献
54.
Wireless Personal Communications - Chronic kidney disease (CKD) is a gradual loss of kidney function over the period of time and it is irrevocable once functionality reaches the critical state.... 相似文献
55.
Antony Butcher Anna L. Stork James P. Verdon J-Michael Kendall Katrin Plenkers Finlay Booth Marcus Boneham Adrian Koe 《岩石力学与岩土工程学报(英文版)》2021,13(3):500-512
Understanding rock strength is essential when undertaking major excavation projects,as accurate assessments ensure both safe and cost-effective engineered slopes.Balancing the cost-safety trade-off becomes more imperative during the construction of critical infrastructure such as nuclear power stations,where key components are built within relatively deep excavations.Designing these engineered slopes is reliant on rock strength models,which are generally parameterised using estimates of rock properties(e.g.unconfined compressive strength,rock disturbance) measured prior to the commencement of works.However,the physical process of excavation weakens the remaining rock mass.Therefore,the model also requires an adjustment for the anticipated rock disturbance.In practice,this parameter is difficult to quantify and as a result it is often poorly constrained.This can have a significant impact on the final design and cost of excavation.We present results from passive and active seismic surveys,which image the extent and degree of disturbance within recently excavated slopes at the construction site of Hinkley Point C nuclear power station.Results from active seismic surveys indicate that the disturbance is primarily confined to 0.5 m from the excavated face.In conjunction,passive monitoring is used to detected seismic events corresponding to fracturing on the cm-scale and event locations are in agreement with 0.5 m of disturbance into the rock face.This suggests rock disturbance at this site is relatively low and occurred during and immediately after the excavation.A ratio of seismic velocities recorded before and after excavations are used to determine the disturbance parameter required for the Hoek-Brown rock failure criterion,and we assess that rock disturbance is low with the magnitude of the disturbance diminishing more quickly than expected into the excavated slope.Seismic methods provide a low-cost and quick method to assess excavation related rock mass disturbance,which can lead to cost reductions in large excavation projects. 相似文献
56.
Joseph Antony Eapen Merin K. Mampilly Maryann Ephraim Sajith V. 《Metallurgical and Materials Transactions A》2021,52(9):3689-3693
Metallurgical and Materials Transactions A - The present work compares the corrosion resistance properties of electrophoretically deposited MoS2 and WS2 nanosheets coatings on mild steel.... 相似文献
57.
Sathish Rajendran Antony George Zian Tang Christof Neumann Andrey Turchanin Leela Mohana Reddy Arava 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(44):2303625
Solid-state lithium metal batteries with garnet-type electrolyte provide several advantages over conventional lithium-ion batteries, especially for safety and energy density. However, a few grand challenges such as the propagation of Li dendrites, poor interfacial contact between the solid electrolyte and the electrodes, and formation of lithium carbonate during ambient exposure over the solid-state electrolyte prevent the viability of such batteries. Herein, an ultrathin sub-nanometer porous carbon nanomembrane (CNM) is employed on the surface of solid-state electrolyte (SSE) that increases the adhesion of SSE with electrodes, prevents lithium carbonate formation over the surface, regulates the flow of Li-ions, and blocks any electronic leakage. The sub-nanometer scale pores in CNM allow rapid permeation of Li-ions across the electrode–electrolyte interface without the presence of any liquid medium. Additionally, CNM suppresses the propagation of Li dendrites by over sevenfold up to a current density of 0.7 mA cm−2 and enables the cycling of all-solid-state batteries at low stack pressure of 2 MPa using LiFePO4 cathode and Li metal anode. The CNM provides chemical stability to the solid electrolyte for over 4 weeks of ambient exposure with less than a 4% increase in surface impurities. 相似文献
58.
Gabriel L. Szabo Benedykt R. Jany Helmut Muckenhuber Anna Niggas Markus Lehner Arkadiusz Janas Paul S. Szabo Ziyang Gan Antony George Andrey Turchanin Franciszek Krok Richard A. Wilhelm 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(26):2207263
Experimental results on the charge-state-dependent sputtering of metallic gold nanoislands are presented. Irradiations with slow highly charged ions of metallic targets were previously considered to show no charge state dependent effects on ion-induced material modification, since these materials possess enough free electrons to dissipate the deposited potential energy before electron-phonon coupling can set in. By reducing the size of the target material down to the nanometer regime and thus enabling a geometric energy confinement, a possibility is demonstrated to erode metallic surfaces by charge state related effects in contrast to regular kinetic sputtering. 相似文献
59.
60.
Harsha Mahadevan A.R. Nayana V. Viswadas Sibin Antony Vinu V. Dev Sandhya Sudhakaran Helan Priya Pious K. Anoop Krishnan 《Advanced Powder Technology》2019,30(1):98-110
In our laboratory, we synthesized a novel surface tailored activated charcoal in removing nitrite species from fertilizer industrial effluents. A customized high temperature carbonate-steam activation technique was adopted to develop the sodium carbonate impregnated activated charcoal (SCIAC). The surface properties of the material were determined using SEM, TG and X-RD techniques. Batch adsorption experiments were performed for optimizing various conditions such as solution pH, contact time, temperature and adsorbent dose for maximizing the nitrite adsorption onto SCIAC. Considerably, a very high nitrite adsorption percentage of 83.8 was obtained for an initial nitrite concentration of 5.0?mg/L at pH 3.0. Among the various equilibrium and kinetic models, Freundlich and pseudo-second-order expressions, respectively, were well enough to explain the adsorption processes. In general, it may conclude that the change in surface characteristics of the adsorbent material after the pyrolysis process is highly favorable for effective removal of nitrite ions from aqueous systems. Adsorption capacity of SCIAC was 27.03?mg/g and studies revealed that the material was feasible in removing nitrite from industrial effluents. 相似文献