scholarly journals Photocatalytic Degradation of Pharmaceuticals Carbamazepine, Diclofenac, and Sulfamethoxazole by Semiconductor and Carbon Materials: A Review

Molecules ◽  
2019 ◽  
Vol 24 (20) ◽  
pp. 3702 ◽  
Author(s):  
Ana S. Mestre ◽  
Ana P. Carvalho
Keyword(s):  
Large Scale ◽  
Carbon Materials ◽  
High Energy ◽  
Carbon Quantum Dots ◽  
Solar Irradiation ◽  
Nanoporous Carbons ◽  
Promising Strategy ◽  
Photocatalytic Removal ◽  
Treatment Technologies

The presence of pharmaceutical compounds in the environment is a reality that calls for more efficient water treatment technologies. Photocatalysis is a powerful technology available but the high energy costs associated with the use of UV irradiation hinder its large scale implementation. More sustainable and cheaper photocatalytic processes can be achieved by improving the sunlight harvesting and the synthesis of semiconductor/carbon composites has proved to be a promising strategy. Carbamazepine, diclofenac, and sulfamethoxazole were selected as target pharmaceuticals due to their recalcitrant behavior during conventional wastewater treatment and persistence in the environment, as properly reviewed. The literature data on the photocatalytic removal of carbamazepine, diclofenac, and sulfamethoxazole by semiconductor/carbon materials was critically revised to highlight the role of the carbon in the enhanced semiconductor performance under solar irradiation. Generally it was demonstrated that carbon materials induce red-shift absorption and they contribute to more effective charge separation, thus improving the composite photoactivity. Carbon was added as a dopant (C-doping) or as support or doping materials (i.e., nanoporous carbons, carbon nanotubes (CNTs), graphene, and derived materials, carbon quantum dots (CQDs), and biochars) and in the large majority of the cases, TiO2 was the semiconductor tested. The specific role of carbon materials is dependent on their properties but even the more amorphous forms, like nanoporous carbons or biochars, allow to prepare composites with improved properties compared to the bare semiconductor. The self-photocatalytic activity of the carbon materials was also reported and should be further explored. The removal and mineralization rates, as well as degradation pathways and toxicity of the treated solutions were also critically analyzed.

FEATURES OF PHOTOCONDUCTIVITY OF Ge AND Si WITH DISORDERED REGIONS

2010 ◽  
Vol 24 (31) ◽  
pp. 2985-2996 ◽  
Author(s):  
V. YEVSEYEV
Keyword(s):  
Large Scale ◽  
High Energy ◽  
Fast Neutrons ◽  
Potential Relief ◽  
Photoelectrical Properties ◽  
Recombination Centers ◽  
First Time ◽  
High Energy Particles ◽  
Disordered Regions

Influence of large radiation defects — disordered regions on photoconductivity of semiconductors Ge and Si , compensated as a result of an irradiation with fast neutrons and 1 GeV protons, is investigated. For the first time, the combined role of disordered regions and a large-scale potential relief in photoelectrical properties of Ge and Si , irradiated by high energy particles is defined. The model of photoconductivity that takes into consideration disordered regions as specific sensitizing recombination centers and allows formation of the spatial potential relief is developed.

A carbon-based material with hierarchical structure and intrinsic heteroatom for sodium-ion storage with ultrahigh rate and capacity

Nanoscale ◽  
2021 ◽  
Author(s):  
Xue-Yang Cui ◽  
Xiao-Dong Lin ◽  
Yajing Wang ◽  
Pan Xu ◽  
Xiaoxiang Fan ◽  
...  
Keyword(s):  
Power Density ◽  
High Power ◽  
Large Scale ◽  
Carbon Materials ◽  
High Energy ◽  
Sodium Ion ◽  
High Power Density ◽  
Sodium Ions ◽  
Ion Storage ◽  
Sodium Ion Storage

The storage of sodium ions with carbon materials has huge potential for large-scale application due to its resourceful and environmental advantage. However, how to realize high power density, high energy...

Ground-based measurements of turbulence in electrified clouds

2020 ◽  
Author(s):  
Evgeny Mareev ◽  
Vladimir Klimenko ◽  
Lev Lubyako ◽  
Mariya Shatalina ◽  
Svetlana Dementyeva ◽  
...  
Keyword(s):  
Electric Field ◽  
Brightness Temperature ◽  
Large Scale ◽  
High Energy ◽  
Passive Microwave ◽  
Theoretical Studies ◽  
Turbulence Characteristics ◽  
Electrical Structure ◽  
Convective Clouds

<p>A problem of the electric field dynamics in turbulent electro-active clouds (Cumulus, Stratus, Cumulonimbus) is one of the most relevant and complex problems of dynamical meteorology and atmospheric electricity. This problem is important for the study of intense large-scale electric field and its fluctuations that may lead to high-energy particle flows and lightning discharges, for electric current parameterization. Direct field measurements in convective clouds with a developed electrical structure are very difficult; so one of urgent tasks is the development of remote sensing methods for turbulence characteristics in electro-active clouds.</p><p>The growth of a large-scale electric field in a turbulent atmosphere is caused by the generation of an electric charge on colliding particles (hydrometeors and dust). Meanwhile, observations (including preliminary observations of the authors) and theoretical studies (Mareev and Dementyeva, 2017) show that intensification of thunderstorm activity can be associated with increased turbulence in the cloud. This paper presents new ideas and results of experimental and theoretical studies of the role of turbulence in electro-active clouds.</p><p>The main attention is paid to complex remote observations of different types of clouds with an experimental set-up including the microwave radiometers of 3 cm and 8 mm wavelengths (with a time resolution of order of one second), the network of electrostatic fluxmeters spaced by several kilometers each from another, and the meteorological radar. The data of recent several years were used for analysis. Note that recently space-borne passive microwave radiometry of intense convective clouds (see, for example, Peterson et al., 2017) attracted more attention compared to ground-based microwave observations. A principal idea of our approach is to use the wave-length channels allowing us to reveal both optically thick and optically transparent cloud events from the data on fluctuations in the brightness temperature of the atmosphere.</p><p>A special attention was paid to comparative analysis of the turbulence characteristics in thunderclouds and in clouds that do not have a developed electrical structure. The spectral characteristics of electric field and brightness fluctuations were found to be associated with atmospheric air turbulence and mostly are quantitatively described by Kolmogorov-type spectra. Compared with ordinary Cumulus and Stratus clouds, a limited band near a frequency of ~ 0.01 Hz with a higher level of fluctuations is distinguished in the spectral density of fluctuations in the brightness temperature of thunderclouds. The spectra of fluctuations of the electric field caused by thunderclouds, as well as turbulence interior thundercloud, are significantly different from the spectra caused by ordinary Cumulus and layered clouds.</p><p>The work was supported by the Russian Foundation for Basic Research (projects no. 19-05-00975 and 18-45-520010).</p><p>References</p><p>Mareev E.A., Dementyeva S.O. (2017), The role of turbulence in thunderstorm, snowstorm, and dust storm electrification. Journal of Geophysical Research: Atmospheres, V. 122, No. 13, P. 6976-6988. doi: 10.1002/2016JD026150.</p><p>Peterson M., Liu C., Mach D., Deierling W., Kalb C. (2015), A method of estimating electric fields above electrifi_ed clouds from passive microwave observations. J. Atmos. Ocean. Tech., V.32 (8), P.1429-1446. doi: 10.1175/ JTECH-D-14-00119.1.</p>

scholarly journals Synthesized Cluster Head Selection and Routing for Two Tier Wireless Sensor Network

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Keyur Rana ◽  
Mukesh Zaveri
Keyword(s):  
Wireless Sensor Network ◽  
Sensor Network ◽  
Large Scale ◽  
Cluster Head ◽  
Integrated Approach ◽  
High Energy ◽  
Wireless Sensor ◽  
Cluster Head Selection ◽  
Cluster Heads

Large scale sensor networks can be efficiently managed by dividing them into several clusters. With the help of cluster heads, each cluster communicates using some routing schedule. It is essential to rotate the role of cluster heads in a cluster to distribute energy consumption if we do not have dedicated high energy cluster heads. Usually routing and cluster head selection for such networks have been separately solved. If cluster heads are selected with the consideration of routing and routing schedule is prepared with the consideration of selected cluster heads, it can help each other. We have proposed an integrated approach of cluster head selection and routing in two tier wireless sensor network (WSN) using Genetic Algorithm based cluster head selection with A-Star algorithm based routing method to extend life of WSN. This approach can lead to significant improvements in the network lifetime over other techniques.

Laser interstitial thermal therapy for treatment of post-radiosurgery tumor recurrence and radiation necrosis

2014 ◽  
Vol 3 (2) ◽  
Author(s):  
Toral R. Patel ◽  
Veronica L.S. Chiang
Keyword(s):  
Large Scale ◽  
Thermal Therapy ◽  
Single Institution ◽  
Laser Interstitial Thermal Therapy ◽  
Metastatic Lesions ◽  
Promising Strategy ◽  
Intracranial Metastases ◽  
Traditional Approaches

AbstractBackground and objective:Approximately one-third of all intracranial metastatic lesions treated with stereotactic radiosurgery (SRS) will regrow at some point during follow-up. A fraction of these lesions will require further therapy. Traditional approaches will work in a majority of, but not all, cases. Laser interstitial thermal therapy (LITT) represents a promising strategy for treatment of regrowing lesions post-SRS that are refractory to standard therapies.Materials and methods:Published literature to evaluate the role of LITT for treatment of regrowing metastatic lesions post-SRS is reviewed; own single institution experience treating these pathologies with two different commercially available LITT systems is included.Results:Early clinical studies have established that LITT can be used to successfully treat post-SRS regrowing lesions. Patients treated with LITT demonstrate both clinical and radiographic improvements following treatment, with minimal side effects.Conclusions:LITT is a promising new therapy for the management of post-SRS regrowing intracranial metastases. Large-scale clinical trials demonstrating therapeutic efficacy must be completed prior to widespread adoption of this technique.

scholarly journals Importance of Carbon Porosity for Energy-Related Applications

2019 ◽  
Vol 21 (3) ◽  
pp. 183
Author(s):  
T.J. Bandosz
Keyword(s):  
Carbon Materials ◽  
High Surface ◽  
High Surface Area ◽  
Carbon Matrix ◽  
Nanoporous Carbons ◽  
Metal Free ◽  
Reduction Processes ◽  
Target Molecules ◽  
Positive Effect

Nanoporous carbons have many advantages over other adsorbents. This includes their high surface area, pore volume and also conductivity of a carbon matrix. The latter is very important for electrocatalysis. In recent years carbon materials have gained a lot of attention as metal-free catalysts. Their catalytic centers have been linked mainly to nitrogen and sulfur heteroatoms incorporated to the carbon matrix. So far, the research efforts have focused mainly on nanoforms of carbons such a graphene and carbon nanotube (CNT). Inspired by those results, we have performed CO2 and O2 electroreduction on nanoporous carbons assuming that small pores, similar in sizes to target molecules, can enhance the efficiency of these catalytic processes. Indeed, the results suggested that even though the N- and S- based catalytic centers are important, adsorption of O2 or CO2/CO2-/CO/H2 in pores has a positive effect on these overall reduction processes. This minireview summarizes our recent results on the role of porosity in electrocatalysis on porous carbons.

scholarly journals Treatment Technologies for Cooling Water Blowdown: A Critical Review

2021 ◽  
Vol 14 (1) ◽  
pp. 376
Author(s):  
Mariam Soliman ◽  
Fadwa Eljack ◽  
Monzure-Khoda Kazi ◽  
Fares Almomani ◽  
Elalim Ahmed ◽  
...  
Keyword(s):  
Energy Demand ◽  
Large Scale ◽  
Wastewater Treatment Plants ◽  
Water Discharge ◽  
Cooling Water ◽  
High Energy ◽  
Membrane Distillation ◽  
Gulf States ◽  
Treatment Technologies ◽  
High Concentrations

Cooling water blowdown (CWBD) generated from different industries and district cooling facilities contains high concentrations of various chemicals (e.g., scale and corrosion inhibitors) and pollutants. These contaminants in CWBD streams deem them unsuitable for discharge into surface water and some wastewater treatment plants. The pollutants present in CWBD, their sources, and the corresponding impacts on the ecosystem are discussed. The international and regional (Gulf states) policies and regulations related to contaminated water discharge standards into water bodies are examined. This paper presents a comprehensive review of the existing and emerging water treatment technologies for the treatment of CWBD. The study presents a comparison between the membrane (membrane distillation (MD), reverse osmosis (RO), nanofiltration (NF), and vibratory shear enhanced membrane process (VSEP)) and nonmembrane-based (electrocoagulation (EC), ballasted sand flocculation (BSF), and electrodialysis (ED)) technologies on the basis of performance, cost, and limitations, along with other factors. Results from the literature revealed that EC and VSEP technologies generate high treatment performance (EC~99.54% reduction in terms of silica ions) compared to other processes (membrane UF with reduction of 65% of colloidal silica). However, the high energy demand of these processes (EC~0.18–3.05 kWh/m3 and VSEP~2.1 kWh/m3) limit their large-scale applications unless connected with renewable sources of energy.

The Role of Sense of Direction and Other Factors During Navigation in a Large-Scale, Unconstrained Environment

2013 ◽  
Author(s):  
Elisabeth J. Ploran ◽  
Ericka Rovira ◽  
James C. Thompson ◽  
Raja Parasuraman
Keyword(s):  
Large Scale ◽  
Sense Of Direction

Magnetic Properties of xCeO2•(50 − x) PbO•50B2O3 Glasses and Glass Ceramics

2017 ◽  
Vol 13 (1) ◽  
pp. 4486-4494 ◽  
Author(s):  
G.El Damrawi ◽  
F. Gharghar
Keyword(s):  
Magnetic Properties ◽  
Large Scale ◽  
Glass Ceramics ◽  
Magnetic Behavior ◽  
Crystal Formation ◽  
Dual Roles ◽  
Effective Agent ◽  
Ordered Structures ◽  
Essential Change

Cerium oxide in borate glasses of composition xCeO2·(50 − x)PbO·50B2O3 plays an important role in changing both microstructure and magnetic behaviors of the system. The structural role of CeO2 as an effective agent for cluster and crystal formation in borate network is clearly evidenced by XRD technique. Both structure and size of well-formed cerium separated clusters have an effective influence on the structural properties. The cluster aggregations are documented to be found in different range ordered structures, intermediate and long range orders are the most structures in which cerium phases are involved. The nano-sized crystallized cerium species in lead borate phase are evidenced to have magnetic behavior.  The criteria of building new specific borate phase enriched with cerium as ferrimagnetism has been found to keep the magnetization in large scale even at extremely high temperature. Treating the glass thermally or exposing it to an effective dose of ionized radiation is evidenced to have an essential change in magnetic properties. Thermal heat treatment for some of investigated materials is observed to play dual roles in the glass matrix. It can not only enhance alignment processes of the magnetic moment but also increases the capacity of the crystallite species in the magnetic phases. On the other hand, reverse processes are remarked under the effect of irradiation. The magnetization was found to be lowered, since several types of the trap centers which are regarded as defective states can be produced by effect of ionized radiation. 

The Impact of Quantitative Easing on Emerging Markets – Literature Review

e-Finanse ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 67-76
Author(s):  
Piotr Bartkiewicz
Keyword(s):  
Emerging Markets ◽  
Large Scale ◽  
Empirical Literature ◽  
Quantitative Easing ◽  
Methodological Choices ◽  
The Subject ◽  
Methodological Approaches ◽  
The Impact ◽  
Sufficient Precision

AbstractThe article presents the results of the review of the empirical literature regarding the impact of quantitative easing (QE) on emerging markets (EMs). The subject is of interest to policymakers and researchers due to the increasingly larger role of EMs in the world economy and the large-scale capital flows occurring after 2009. The review is conducted in a systematic manner and takes into consideration different methodological choices, samples and measurement issues. The paper puts the summarized results in the context of transmission channels identified in the literature. There are few distinct methodological approaches present in the literature. While there is a consensus regarding the direction of the impact of QE on EMs, its size and durability have not yet been assessed with sufficient precision. In addition, there are clear gaps in the empirical findings, not least related to relative underrepresentation of the CEE region (in particular, Poland).

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