Evaluation of Caffeine Degradation by Sequential Coupling of TiO2/O3/H2O2/UV Processes

2020 ◽  
Vol 63 (11-14) ◽  
pp. 1361-1373 ◽  
Author(s):  
Jose A. Lara-Ramos ◽  
Gilmer D. Llanos-Diaz ◽  
Jennyfer Diaz-Angulo ◽  
Fiderman Machuca-Martínez
2018 ◽  
Author(s):  
Richard Kong ◽  
Mark Crimmin

<i>The formation of carbon chains by the coupling of COx (X = 1 or 2) units on transition metals is a fundamental step relevant to Fischer-Tropsch catalysis. Fischer-Tropsch catalysis produces energy dense liquid hydrocarbons from synthesis gas (CO and H2) and has been a mainstay of the energy economy since its discovery nearly a century ago. Despite detailed studies aimed at elucidating the steps of catalysis, experimental evidence for chain growth (Cn to Cn+1 ; n > 2) from the reaction of CO with metal complexes is unprecedented. In this paper, we show that carbon chains can be grown from sequential reactions of CO or CO2 with a transition metal carbonyl complex. By exploiting the cooperative effect of transition and main group metals, we document the first example of chain propagation from sequential coupling of CO units (C1 to C3 to C4), along with the first example of incorporation of CO2 into the growing carbon chain.</i><br>


2015 ◽  
Vol 9 (1) ◽  
pp. 58-64 ◽  
Author(s):  
Kuiyang Wang ◽  
Jinhua Tang ◽  
Guoqing Li

In order to optimize the design method and improve the performance of hydraulic retarder, the numerical simulation of multi-field coupling of heat, fluid and solid is carried out to hydraulic retarder, based on the numerical computation and algorithm of heat-fluid coupling and fluid-solid coupling. The computation models of heat-fluid coupling and fluid-solid coupling of hydraulic retarder are created. The three dimensional model of hydraulic retarder is established based on CATIA software, and the whole flow passage model of hydraulic retarder is extracted on the basis of the three dimensional model established. Based on the CFD calculation and the finite element numerical simulation, the temperature field, stress field, deformation and stress state are analysised to hydraulic retarder in the state of whole filling when the rotate speed is 1600 r/min. In consideration of rotating centrifugal force, thermal stress and air exciting vibration force of blade surface, by using the sequential coupling method, the flow field characteristics of hydraulic retarder and dynamic characteristics of blade structure are analysised and researched based on multi-field coupling of heat, fluid and solid. These provide the theoretical foundation and references for parametric design of hydraulic retarder.


LWT ◽  
2019 ◽  
Vol 109 ◽  
pp. 387-394
Author(s):  
Yali Jiang ◽  
Yu Lu ◽  
Youyi Huang ◽  
Shouwen Chen ◽  
Zhixia Ji

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 964
Author(s):  
Rattana Muangmora ◽  
Patiya Kemacheevakul ◽  
Patiparn Punyapalakul ◽  
Surawut Chuangchote

This work presents the development of titanium dioxide (TiO2) film immobilized on circular glass sheets for photocatalytic degradation of caffeine under ultraviolet C (UVC) irradiation. TiO2 was synthesized through the ultrasonic-assisted sol–gel method and immobilized on circular glass sheets by the doctor blade technique. Polyvinylpyrrolidone (PVP) was used to mix with the TiO2 precursor solution to enhance film adhesion on the glass surface. TiO2 film was mainly composed of anatase phase with a small amount of rutile phase. Caffeine removal was found to increase with increasing irradiation time. Caffeine (20 mg/L) in the synthetic wastewater could not be detected after 3 h of UVC irradiation. The reaction rate of caffeine degradation followed the pseudo-first-order model. The concentrated caffeine solutions required a longer irradiation time for degradation. The used TiO2-coated glass sheets could be easily separated from the treated wastewater and reusable. The caffeine removal efficiency of TiO2-coated glass sheets in each cycle maintained a high level (~100%) during fifteen consecutive cycles.


2020 ◽  
Vol 104 (7) ◽  
pp. 3025-3036 ◽  
Author(s):  
Di Sun ◽  
Xueying Yang ◽  
Chao Zeng ◽  
Bo Li ◽  
Yi Wang ◽  
...  

Ocean Science ◽  
2007 ◽  
Vol 3 (3) ◽  
pp. 345-362 ◽  
Author(s):  
G. Jordà ◽  
R. Bolaños ◽  
M. Espino ◽  
A. Sánchez-Arcilla

Abstract. The effects of wave-current interactions on shelf ocean forecasts is investigated in the framework of the MFSTEP (Mediterranean Forecasting System Project Towards Enviromental Predictions) project. A one way sequential coupling approach is adopted to link the wave model (WAM) to the circulation model (SYMPHONIE). The coupling of waves and currents has been done considering four main processes: wave refraction due to currents, surface wind drag and bottom drag modifications due to waves, and the wave induced mass flux. The coupled modelling system is implemented in the southern Catalan shelf (NW Mediterranean), a region with characteristics similar to most of the Mediterranean shelves. The sensitivity experiments are run in a typical operational configuration. The wave refraction by currents seems to be not very relevant in a microtidal context such as the western Mediterranean. The main effect of waves on current forecasts is through the modification of the wind drag. The Stokes drift also plays a significant role due to its spatial and temporal characteristics. Finally, the enhanced bottom friction is just noticeable in the inner shelf.


2019 ◽  
Vol 9 (22) ◽  
pp. 6471-6481 ◽  
Author(s):  
Narasimha Swamy Thirukovela ◽  
Ramesh Balaboina ◽  
Vinayak Botla ◽  
Ravinder Vadde ◽  
Sreekantha Babu Jonnalagadda ◽  
...  

Catalyst efficacy of in situ generated Pd-nanoparticles in the regioselective one-pot synthesis of substituted pyrazoles and isoxazoles via sequential coupling-cyclization methodology in environmentally benign medium is described.


Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 658
Author(s):  
Wenjie Tong ◽  
Wanming Li ◽  
Ximin Zang ◽  
Huabing Li ◽  
Zhouhua Jiang ◽  
...  

A comprehensive mathematical model of electroslag remelting with two series-connected electrodes (TSCE-ESR) was constructed based on sequential coupling method. The influence of droplet effect on electroslag remelting process (ESR) was considered in this model. Compared with one-electrode electroslag remelting (OE-ESR), the multi-physics field, droplet formation and dripping behavior, and molten metal pool structure of TSCE-ESR process were studied. The results show that during the process of TSCE-ESR, the proximity effect of the electrodes suppresses the skin effect, and Joule heat is concentrated in the area between the two electrodes of slag pool, making the temperature distribution of the slag pool more uniform. The heat used to melt the electrode in the process of TSCE-ESR accounts for about 34% of the total Joule heat, which is lower than the OE-ESR (17%). Therefore, it makes a higher melting rate and a smaller droplet size in the process of TSCE-ESR. Compared with OE-ESR, TSCE-ESR process can realize the unification of higher melting rate and shallow flat molten metal pool. Compared with the results without droplet effect, it is found that in the simulation results with droplet effect, the depth and the cylindrical section of molten metal pool increased, and the width of the mushy zone is significantly reduced, which is more consistent with the actual electroslag remelting process.


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