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51.
Harbottle MJ Mantle MD Johns ML Van Herwijnen R Al-Tabbaa A Hutchings TR Moffat AJ Ouki SK 《Environmental science & technology》2007,41(10):3444-3448
The use of a zeolite (clinoptilolite) to protect poplar plants from lithium-contaminated soil has been studied using magnetic resonance imaging. Lithium was used as a model contaminant as it could be tracked directly using specific nuclear magnetic resonance probes, rather than relying on relaxation time effects on protons due to paramagnetic solutes. The sorption of lithium to the zeolite was investigated both in static and dynamic systems; lithium was found to sorb readily to the zeolite over time. Poplar plants were grown in soil microcosms consisting of either sand or sand and zeolite with nutrients provided through the use of Hoagland's solution as the pore fluid. Both one-dimensional profiles of lithium concentration along poplar stems and direct lithium imaging of stem cross-sections were employed to reveal the uptake of the contaminant into the plant structure, showing significantly less lithium present in plants grown in sand and zeolite than those grown in sand alone. Evidence of structural features involved in the uptake of lithium was also obtained. 相似文献
52.
Masood Ahmad Fasee Ullah Ishtiaq Wahid Atif Khan M. Irfan Uddin Abdullah Alharbi Wael Alosaimi 《计算机、材料和连续体(英文)》2021,67(1):321-336
Internet of Everything (IoE) indicates a fantastic vision of the future, where everything is connected to the internet, providing intelligent services and facilitating decision making. IoE is the collection of static and moving objects able to coordinate and communicate with each other. The moving objects may consist of ground segments and flying segments. The speed of flying segment e.g., Unmanned Ariel Vehicles (UAVs) may high as compared to ground segment objects. The topology changes occur very frequently due to high speed nature of objects in UAV-enabled IoE (Ue-IoE). The routing maintenance overhead may increase when scaling the Ue-IoE (number of objects increases). A single change in topology can force all the objects of the Ue-IoE to update their routing tables. Similarly, the frequent updating in routing table entries will result more energy dissipation and the lifetime of the Ue-IoE may decrease. The objects consume more energy on routing computations. To prevent the frequent updation of routing tables associated with each object, the computation of routes from source to destination may be limited to optimum number of objects in the Ue-IoE. In this article, we propose a routing scheme in which the responsibility of route computation (from neighbor objects to destination) is assigned to some IoE-objects in the Ue-IoE. The route computation objects (RCO) are selected on the basis of certain parameters like remaining energy and mobility. The RCO send the routing information of destination objects to their neighbors once they want to communicate with other objects. The proposed protocol is simulated and the results show that it outperform state-of-the-art protocols in terms of average energy consumption, messages overhead, throughput, delay etc. 相似文献
53.
Antoine Venault Chun-Wei Huang Jie Zheng Arunachalam Chinnathambi Sulaiman Ali Alharbi Yu Chang 《国际聚合物材料杂志》2016,65(2):65-74
Polyzwitterionic biomaterial with pH-responsive and hemocompatible dual functions is formulated by the copolymerization of 2-(N, N-dimethyl amino) ethyl methacrylate (DMAEMA) sequences and sulfobetaine methacrylate (SBMA) moieties. Hydrogels are salt responsive, due to the interplay between hydrogen bonds formation, ions solvation, and antipolyelectrolyte effect, while DMAEMA sequences provide pH-responsiveness. Their low-fouling nature is demonstrated using plasma proteins and bacteria. Improved hemocompatibility with SBMA content is unveiled by the resistance to platelet and erythrocyte attachment, as well as from delayed plasma clotting time. Overall, this study suggests that dual-functional zwitterionic hydrogels are promising pH-responsive and hemocompatible polymeric biomaterials. 相似文献
54.
55.
Ashita Sajad A. Loan Abdullah G. Alharbi Mohammad Rafat 《Journal of Computational Electronics》2018,17(3):977-985
In this paper, we propose and simulate two new structures of electron–hole bilayer tunnel field-effect transistors (EHBTFET). The proposed devices are n-heterogate with \(\hbox {M}_{1}\) as overlap gate, \(\hbox {M}_{2}\) as underlap gate and employs a high-k dielectric pocket in the drain underlap. Proposed structure 1 employs symmetric underlaps (Lgs = Lgd = Lu). The leakage analysis of this structure shows that the lateral ambipolar leakage between channel and drain is reduced by approximately three orders, the OFF-state leakage is reduced by one order, and the \(I_{\mathrm{ON}}/I_{\mathrm{OFF}}\) ratio is increased by more than one order at \(V_\mathrm{{GS}}=V_{\mathrm{DS}} =1.0\) V as compared to the conventional Si EHBTFET. The performance is improved further by employing asymmetric underlaps (\(\hbox {Lgs}\ne \hbox {Lgd}\)) with double dielectric pockets at source and drain, called as proposed structure 2. The pocket dimensions have been optimized, and an average subthreshold swing of 17.7 mV/dec (25.5% improved) over five decades of current is achieved with an ON current of \(0.23~\upmu \hbox {A}/\upmu \hbox {m}\) (11% improved) in proposed structure 2 in comparison with the conventional EHBTFET. Further, the parasitic leakage paths between overlap/underlap interfaces are blocked and the OFF-state leakage is reduced by more than two orders. A high \(I_{\mathrm{ON}}/I_{\mathrm{OFF}}\,\hbox {ratio}~>10^{9}\) (two orders higher) is achieved at \(V_{\mathrm{DS}} =V_{\mathrm{GS}} =1.0~\hbox {V}\) in the proposed structure 2 in comparison with the conventional one. 相似文献
56.
57.
Abir Arbel 《Nuclear Engineering and Design》1974,30(1)
Weights and outer volumes of cylindrical and spherical thick-walled pressure vessels which contain a given amount of gas are considered. Decrease of vessel weight demands an increase in inner diameter. The outer diameter of pressure vessels can be minimized when the internal pressure obtains an optimal value. 相似文献
58.
S. Swathi R. Yuvakkumar G. Ravi P. Kumar S.I. Hong Omaima Nasif Sulaiman Ali Alharbi Dhayalan Velauthapillai 《Ceramics International》2021,47(11):15253-15259
Water splitting is an important method for hydrogen production. Notably, tantalum oxide has the potential to employ extensive variety appliances because of its outstanding electrical and optical properties. Tantalum pentoxide (Ta2O5) nanopowders were produced using the sol–gel process. The effect of calcination time plays a main role on Ta2O5 crystal structure configuration. Transmission electron microscope images explored obtained Ta2O5 nanorod formation and investigated by electrochemical studies for its use in electrochemical water-splitting applications. The calculated specific capacitance values of Ta2O5 electrodes at different temperature conditions were 146.4, 191.7, and 221.7 F/g. Fabricated Ta2O5 electrodes showed overpotential of 304, 278, and 267 mV. Current densities of Ta2O5 electrodes at different calcinations times were 353, 419, and 461 mA/g. Ta2O5 powder calcined for 6 h revealed high specific capacitance and low overpotential, indicating better electrochemical reactivity suitable for water oxidation applications. 相似文献
59.
Silicon - In this article, the variable thermal conductivity which it depending on temperature gradient in context of the photothermal excitation process of a semiconductor elastic material is... 相似文献
60.