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101.
Bench-scale experiments investigated the effect of electrolyte mixing on the effectiveness of an electrochemical reactor for the reactivation of granular activated carbon (GAC). Two different GACs (F-400 and WV-B) were loaded with phenol via batch adsorption tests, then electrochemically reactivated and finally reloaded with phenol. Reactivation was conducted in a recirculating flow reactor with a 0.1?M NaCl solution as the electrolyte. Cathodic reactivation was more efficient than the anodic reactivation and increasing the degree of electrolyte mixing decreased the cathodic reactivation efficiencies, while there was no significant change in the anodic reactivation efficiencies. Higher degrees of electrolyte mixing decreased the local pH at the cathode and consequently reduced the desorption driving force and therefore reduced the reactivation efficiency. The electrolyte mixing lowered the cell voltage. However, this advantage was overshadowed by the increased energy consumption required for the electrolyte pumping, the reduction of the oxidation rate of phenol, and a 20% reduction in the reactivation efficiencies. Thus, electrolyte mixing of the electrolyte is not recommended in the electrochemical reactivation of GAC.  相似文献   
102.
    
As the COVID-19 pandemic swept the globe, social media platforms became an essential source of information and communication for many. International students, particularly, turned to Twitter to express their struggles and hardships during this difficult time. To better understand the sentiments and experiences of these international students, we developed the Situational Aspect-Based Annotation and Classification (SABAC) text mining framework. This framework uses a three-layer approach, combining baseline Deep Learning (DL) models with Machine Learning (ML) models as meta-classifiers to accurately predict the sentiments and aspects expressed in tweets from our collected Student-COVID-19 dataset. Using the proposed aspect2class annotation algorithm, we labeled bulk unlabeled tweets according to their contained aspect terms. However, we also recognized the challenges of reducing data’s high dimensionality and sparsity to improve performance and annotation on unlabeled datasets. To address this issue, we proposed the Volatile Stopwords Filtering (VSF) technique to reduce sparsity and enhance classifier performance. The resulting Student-COVID Twitter dataset achieved a sophisticated accuracy of 93.21% when using the random forest as a meta-classifier. Through testing on three benchmark datasets, we found that the SABAC ensemble framework performed exceptionally well. Our findings showed that international students during the pandemic faced various issues, including stress, uncertainty, health concerns, financial stress, and difficulties with online classes and returning to school. By analyzing and summarizing these annotated tweets, decision-makers can better understand and address the real-time problems international students face during the ongoing pandemic.  相似文献   
103.
104.
Multimedia Tools and Applications - Facial point detection gains an increasing importance in computer vision as it plays a vital role in several applications such as facial expression recognition...  相似文献   
105.
Telecommunication Systems - MPLS VPN is growing in front of the other network layer tunneling technologies of the OSI model. The trend related to this technology is justified mainly by the...  相似文献   
106.
This paper presents a new model for nonlinear analysis of reinforced concrete beam–columns with bond–slip. The model is derived from a two-field mixed formulation with independent approximation of forces and displacements. The state determination algorithm for the implementation of the model in a general purpose nonlinear finite-element analysis program is presented and its stability characteristics are discussed. Both, bond–slip and pull-out effects, are represented in the model. The paper concludes with a correlation study to investigate the validity of the model. The study confirmed the accuracy of the model in representing global and particularly local parameters.  相似文献   
107.
Transforming growth factor-beta 1 (TGF-beta 1) is an immuno-modulatory cytokine which has been shown to modulate the activity of T and B cells. We show here that human TGF-beta 1 inhibited stationary cultures of IL-2 dependent CD4+ bovine lymphoblastoid T cells (BLTC) by down-regulating their IL-2 receptor (IL-2R) expression, arresting cells in the G0/G1 compartment of the cell cycle, and inducing these cells to undergo apoptosis. These events were reversed by the addition of a minimal concentration of IL-2 (2U/ml). In the presence of exogenous IL-2, TGF-beta 1 was found to augment the proliferative response of BLTC through up-regulation of IL-2R expression, allow progression of normal cell cycle, and significantly prevent apoptosis. Our data clearly show that IL-2 and TGF-beta 1, when present alone, have contrasting effects on BLTC. TGF-beta 1 down regulates events that are associated with IL-2 mediated signal. But when present together, IL-2 and TGF-beta 1 upregulate activation signals and proliferation of rapidly dividing CD4+T cells.  相似文献   
108.
Wireless Networks - Using efficiently the wireless sensor networks based on IEEE 802.15.4/zigbee remains a real challenge for the forest fire detection and monitoring applications. The most...  相似文献   
109.
A review is provided of indices and methods for evaluating power system reliability performance using probability theory. Particular emphasis is placed on development since about 1960, when a stochastic process view of power systems was used for reliability evaluation. The present status of such evaluation is given, and desirable areas of further research are outlined.  相似文献   
110.
    
Equilibrium and kinetics of exchange of 60Co and 152+154Eu radionuclides on hydrous titanium oxide incorporated in polyacrylonitrile, TiO-OH-PAN, were studied. The capacities of TiO-OH-PAN for 60Co and 152+154Eu were found to be 2.35 and 2.69 meq/g respectively. Freundlich and Langmiur isotherms were investigated. The validity of the Langmuir isotherm over the specified concentration range indicates monolayer coverage of the surface of TiO-OH-PAN by cobalt and europium. Sorption data was treated with the Dubinin-Radushkevich equation. The results indicated that hydrous titanium oxide incorporated in polyacrylonitrile can be considered as a promising material for removal of cobalt and europium ions from aqueous solution.  相似文献   
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