scholarly journals The Influence of the Configuration of Two Electrochemical Reactors on the Process of Removing Atrazine from Water

2021 ◽  
Vol 13 (9) ◽  
pp. 5267
Author(s):  
Juan Nápoles-Armenta ◽  
Juan Antonio Vidales-Contreras ◽  
Luis Alonso Leyva-Soto ◽  
Edna Rosalba Meza-Escalante ◽  
Lourdes Mariana Díaz-Tenorio ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Energy Consumption ◽  
Treatment Time ◽  
Lead Dioxide ◽  
Anode Current ◽  
Recirculation Flow ◽  
Significant Difference ◽  
Electro Oxidation ◽  
Oxidation Reactor ◽  
Ti Mesh

In Mexico, atrazine is widely used in agriculture to control broadleaf weeds. The objective of this research was to compare atrazine removal in water and energy consumption between an up-flow cylinder electro-oxidation reactor (UCER) and an up-flow rectangular electro-oxidation reactor (URER) using the response surface methodology. In each reactor, two titanium (Ti) mesh electrodes (cathodes) and one Titanium-Lead Dioxide (Ti-PbO2) mesh electrode (anode). Current intensity effects, electrolysis treatment time, and recirculation flow were evaluated. Synthetic water with 5 mg/L atrazine content was used. Optimum atrazine removal values were obtained at 2 A electric current, 180 min of treatment time, and 200 mL/min recirculation rate for both reactors: in these conditions an atrazine removal of 77.45% and 76.89% for URER and UCER respectively. However, energy consumption showed a significant difference of 137.45 kWh/m3 for URER and 73.63 kWh/m3 for UCER. Regarding energy efficiency, a 60% atrazine removal was reached in both reactors using less energy for UCER at (1.5 A–135 min–150 mL/min–25.8 kWh/m3) and for URER at (0.66 A–135 min–150 mL/min–20.12 kWh/m3).

P-Removal in Completely Mixed Systems

1985 ◽  
Vol 17 (11-12) ◽  
pp. 325-326 ◽  
Author(s):  
H J. G. W. Donker ◽  
P. Opic ◽  
H. P. de Vries
Keyword(s):  
Mixed System ◽  
Domestic Waste ◽  
Recirculation Flow ◽  
Start Up ◽  
Significant Difference ◽  
Aerobic Reactor ◽  
The Difference ◽  
Positive Effect ◽  
Mixed Systems ◽  
P Removal

Ca. 60 % of the Dutch activated sludge plants consist of completely mixed systems, experiments have been carried out in completely mixed pilot plants to study the biological P-removal. The research was carried out in two pilot plants. The pilot plants consisted of: anaerobic reactor, anoxic reactor, aerobic reactor and a clarifier. All the reactors were completely mixed. Both plants were fed with settled domestic waste water at a sludge loading of 400 and 250 g COD/kg sludge.day respectively. The results are given below:sludge loading (g COD/kg sludge.day)400400250ratio Anaerobic : Anoxic : Aerobic1: 1:2,71:1:4,11:1:2,7P-removal (%)802875N-removal (%)505065COD-removal (%)858585 It has been shown that there is no significant difference between the results at the two different sludge loadings. Remarkable is the difference between the ratio 1:1:2,7 in combination with the internal recirculation flow anoxic-anaerobic of 160 % and the ratio 1:1:4,1 with a recirculation flow of 30 %. During the start-up at a sludge loading of 250 g COD/kg sludge.day and an internal recirculation flow of 30 %, bulking sludge developed almost immediately. The Premoval was completely disturbed. Increasing the internal recirculation flow to 160% had a positive effect on settling properties and P-removal. This investigation has pointed out that a completely mixed system is suitable for biological P-removal, without negatively affecting the nitrification. Important factors in the process are the ratio anaerobic:anoxic:aerobic and the recirculation flows.

Production of grape pekmez by Ohmic heating-assisted vacuum evaporation

2021 ◽  
pp. 108201322199161
Author(s):  
Merve Tuçe Tunç ◽  
Arda Akdoğan ◽  
Cemalettin Baltacı ◽  
Zeliha Kaya ◽  
Halil İbrahim Odabaş
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Ohmic Heating ◽  
Vacuum Evaporation ◽  
Voltage Gradient ◽  
Evaporation Process ◽  
Significant Difference ◽  
Total Process ◽  
Energy Consumptions ◽  
Voltage Gradients

Pekmez is a concentrated syrup-like food conventionally produced by vacuum evaporation process from sugar-rich fruits. In this study, the applicability of grape pekmez production by ohmic heating assisted vacuum evaporation (ΩVE) method was investigated. Conventional vacuum evaporation (CVE) and ΩVE methods were compared in terms of physicochemical properties, HMF (5-hydroxymethylfurfural) contents, rheological properties, and energy consumptions. ΩVE was run at four different voltage gradients (17.5, 20, 22.5, and 25 V/cm). Total process times for grape pekmez production were determined as 57, 28.5, 32, 39, and 50 minutes for CVE, ΩVE (25 V/cm), ΩVE (22.5 V/cm), ΩVE (20 V/cm) and ΩVE (17.5 V/cm), respectively. Energy consumption of CVE method was higher than ΩVE method for all voltage gradients. Energy efficiency increased as the voltage gradient increased. There was no significant difference between CVE and ΩVE methods for HMF contents. The results show that the ΩVE method could be an alternative to the CVE process for grape pekmez production.

scholarly journals Comparative study to evaluate dosimetric differences in patients of locally advanced carcinoma cervix undergoing intracavitary brachytherapy under two different anaesthesia techniques: an audit from a tertiary cancer centre in India

2019 ◽  
Vol 31 (1) ◽  
Author(s):  
Divyesh Kumar ◽  
G. Y. Srinivasa ◽  
Ankita Gupta ◽  
Bhavana Rai ◽  
Arun S. Oinam ◽  
...  
Keyword(s):  
Day Care ◽  
Treatment Time ◽  
Locally Advanced ◽  
Effective Alternative ◽  
External Beam Radiation ◽  
Intracavitary Brachytherapy ◽  
High Dose ◽  
Carcinoma Cervix ◽  
Beam Radiation ◽  
Significant Difference

Abstract Background Carcinoma cervix is amongst the leading causes of mortality and morbidity in women population worldwide. High-dose-rate intracavitary brachytherapy (HDR-ICBT) post external beam radiation therapy (EBRT) is the standard of care in managing locally advanced stage cervical cancer patients. HDR-ICBT is generally performed under general anaesthesia (GA) in operation theatre (OT), but due to logistic reasons, sometimes, it becomes difficult to accommodate all patients under GA. Since prolonged overall treatment time (OTT) makes the results inferior, taking patients in day care setup under procedural sedation (PS) can be an effective alternative. In this audit, we tried to retrospectively analyse the dosimetric difference, if any, in patients who underwent ICBT at our centre, under either GA in OT or PS in day care. Results Thirty five patients were analysed 16/35 (45.71%) patients underwent HDR-ICBT under GA while 19/35 (54.28%) patients under PS. In both groups, a statistically significant difference was observed between the dose received by 0.1 cc as well as 2 cc of rectum (p < 0.05), while the bladder and sigmoid colon had comparable dosages. Conclusion Though our dosimetric analysis highlighted better rectal sparing in patients undergoing HDR-ICBT under GA when compared to patients under PS, PS can still be considered an effective alternative, especially in centres dealing with significant patient load. Further studies are required for firm conclusion.

Sulfide-oxidation-assisted electrochemical water splitting for H2 production on a bifunctional Cu2S/nickel foam catalyst

2021 ◽  
Author(s):  
Yuhou Pei ◽  
Jiong Cheng ◽  
Heng Zhong ◽  
Zhenfeng Pi ◽  
Zhao Yu ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Water Splitting ◽  
Hydrogen Evolution Reaction ◽  
Oxygen Evolution Reaction ◽  
Oxidation Reaction ◽  
Nickel Foam ◽  
Sulfide Oxidation ◽  
H2 Production ◽  
Electro Oxidation ◽  
Electrochemical Water Splitting

Replacing the sluggish oxygen evolution reaction (OER) by sulfide electro-oxidation reaction (SOR) could be a promising way to decrease the energy consumption for hydrogen evolution reaction (HER) and to treat...

Potency of Three Botanical Oils Against the Aphis Craccivora Koch (Homoptera: Aphididae) Nymphs Under Laboratory Conditions

2021 ◽  
Vol 19 (1) ◽  
pp. 139-154
Author(s):  
MA Hossain ◽  
MS Yasmin ◽  
MAA Bachchu ◽  
MA Alim
Keyword(s):  
Treatment Time ◽  
Probit Analysis ◽  
Aphis Craccivora ◽  
Tween 20 ◽  
Laboratory Conditions ◽  
Significant Difference ◽  
Aphis Craccivora Koch ◽  
Insect Mortality ◽  
Oil Repellent ◽  
Swietenia Mahagoni

Botanicals are promising and attractive alternatives for pest management. In the present study, three botanical oils namely neem (Azadirachta indica), karanja (Pongamia pinnata) and mehogony (Swietenia mahagoni) were tested against the nymphs of Aphis craccivora Koch to evaluate the toxic and repellent effects under laboratory conditions (25 ± 5oC, 65-75% RH). Four concentrations (0.5, 1.0, 1.5, and 2.0%) along with control were maintained with distilled water and tween-20 was used as emulsifier. Leaf dipped method were used for insect bioassay. Insect mortality was recorded at 24, 48 and 72 hours after intervals while repellency was carried out at 2 hours after intervals upto 10th hours and the collected data were analyzed through MSTAT-C program. Results indicated that all the tested oils had toxic and repellent effects against the A. craccivora nymphs. Among the tested botanical oils, no significant difference was observed in terms of mortality over treatment time. But significant difference was noticed over level of concentrations exerted by the botanical oils. The average highest mortality (28.62%) was recorded by the application of mehogony oil whereas neem oil showed the lowest mortality (27.21%) against the A. craccivora and the mortality was directly proportional to the level of concentrations and hour after treatment (HAT). Probit analysis showed the lowest LD50 values of mehogony oil which revealed the highest toxic effect against the nymph of bean aphid. The highest repellent effect (77.33%) was found in mehogony oil (repellent class IV) among all the botanical oils applied. On the contrary, neem (57.33%) and karanja (55.00%) oils belonged to the same repellent class that is repellent class II. Although all the tested botanical oils evaluated showed toxic and repellent effects but mehogony oil performed as the best potent oil against the nymphs. We therefore suggested using the mehogony oil for the management of bean aphid. SAARC J. Agric., 19(1): 139-154 (2021)

scholarly journals Treatment time, outcome, and anchorage loss comparisons of self-ligating and conventional brackets

2012 ◽  
Vol 83 (2) ◽  
pp. 280-285 ◽  
Author(s):  
Ferdinand M. Machibya ◽  
Xingfu Bao ◽  
Lihua Zhao ◽  
Min Hu
Keyword(s):  
Treatment Time ◽  
Peer Assessment ◽  
Steel Wire ◽  
Skeletal Changes ◽  
Lateral Cephalograms ◽  
Significant Difference ◽  
Conventional Brackets ◽  
Orthodontic Patients ◽  
Anchorage Loss ◽  
Mandibular Incisors

ABSTRACT Objective: To compare the treatment time, outcome, and anchorage loss among orthodontic patients treated by self-ligating brackets (SLBs) and conventional brackets (CBs). Materials and Methods: A retrospective cohort study compared 34 patients (SLB group) treated by SmartClip brackets (3M Unitek, Monrovia, Calif) to 35 patients (CB group) treated by conventional preadjusted Victory series brackets (3M Unitek) and ligated by stainless steel wire ligatures. Pretreatment (T1) and posttreatment (T2) lateral cephalograms were traced and analyzed using Pancherz sagittal-occlusion analysis to obtain skeletal and dental changes in the maxilla and the mandible. The dental cast models were assessed by the Peer Assessment Rating (PAR) Index for the treatment outcomes. Results: The mean treatment time for SLBs (19.19 months) did not show a statistically significant difference from 21.25 months of CBs; the treatment time and pretreatment PAR scores were strongly correlated. There was no difference in anchorage loss between the SLB and CB groups. There were significant dental and skeletal changes among adolescent orthodontic patients regardless of the bracket used. The lingual inclination of the mandibular incisors in the CB group was 3.62° more than in the SLB group (P &lt; .01). Conclusions: The treatment time and anchorage loss are not influenced by the type of bracket used. There are significant dental and skeletal changes among adolescent orthodontic patients regardless of the bracket used. There is significantly greater lingual inclination of mandibular incisors in the CB group than in the SLB group.

Laccase-catalyzed functionalization with 4-hydroxy-3-methoxybenzylurea significantly improves internal bond of particle boards

Holzforschung ◽  
2008 ◽  
Vol 62 (2) ◽  
pp. 223-229 ◽  
Author(s):  
Karin Fackler ◽  
Thomas Kuncinger ◽  
Thomas Ters ◽  
Ewald Srebotnik
Keyword(s):  
Internal Bond ◽  
Treatment Time ◽  
Urea Formaldehyde ◽  
Treated Wood ◽  
Untreated Wood ◽  
Strength Properties ◽  
Positive Interactions ◽  
Formaldehyde Resin ◽  
Significant Difference ◽  
Wood Particles

Abstract Enzymatic functionalization is an attractive tool to provide a reactive interface for further processing of lignocellulosic materials, such as wood particles and fibers. Here, spruce wood particles have been functionalized by fungal laccase combined with 4-hydroxy-3-methoxy-benzylamine (HMBA) or 4-hydroxy-3-methoxybenzylurea (HMBU). The expectation was crosslinking with resins in subsequent glueing processes, which should improve strength properties of particle boards. Essential process parameters, such as liquid to solid mass ratio and treatment time, were optimized on a laboratory scale resulting in HMBA and HMBU binding yields of 90% and above as determined by radiochemical mass balance analysis. We employed a multifactorial experimental design for board production from treated wood particles and urea/formaldehyde resin. Mechanical testing and multivariate data analysis revealed, for the first time, an increase of internal bond (IB) as a result of functionalization with HMBU. HMBA was not successful. Variance analysis of relevant parameters and their interactions demonstrated a highly significant difference (P>99.99%) between boards treated with laccase/HMBU versus untreated wood particles. Due to positive interactions, functionalization was most effective at high bulk density (750 kg m-3) and high resin content (10%) resulting in a calculated IB improvement of 0.12 N m-2 (21%).

scholarly journals Energy Monitoring System for Existing Buildings in Indonesia

2018 ◽  
Vol 42 ◽  
pp. 01003
Author(s):  
Sentagi Sesotya Utami ◽  
Faridah ◽  
Na’im A. Azizi ◽  
Erlin Kencanawati ◽  
M. Akbar Tanjung ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Monitoring System ◽  
Local Governments ◽  
Energy Savings ◽  
Performance Testing ◽  
Cost Effective ◽  
Existing Buildings ◽  
Energy Monitoring ◽  
Building Permit ◽  
Significant Difference

Current studies conducted by JICA, AMPRI and IFC-World Bank, reported that large commercial buildings in Indonesia are not energy and water efficient. One of the cause is the lack of regulation. Meanwhile, effective regulations to reduce energy and water consumption are the concern mostly in a new building to obtain a building permit. This strategy is understandable as retrofitting existing buildings are often more difficult to be implemented, and enforcement is still a major issue in Indonesia. Local governments are currently working on streamlining building permit process as well as developing an online monitoring system for existing buildings. By applying a Building Energy Management System (BEMS) enables to reduce energy consumption up to 15%. An energy monitoring system was designed and installed through this research for Department of Nuclear Engineering and Engineering Physics (DNEEP) building, Faculty of Engineering, Universitas Gadjah Mada. It is a 20 years old two-story building used for educational activities, which consist of classrooms, laboratories, offices and storage spaces. An audit energy was done recently in 2015 where an energy consumption of 261.299,636 kWh/year.m2 was reported. In the existing condition, a power meter is inaccessible and therefore, the only feedback of occupancy behavior in the energy consumption is through the electricity bill. The previous study has shown that building occupants would behave more efficiently if the amount of energy used is notified, and the amount of energy savings are recorded. However, these energy monitoring systems are considered expensive and uniquely tailored for every building. This research aims to design and install a cost effective BEMS based on occupant’s satisfactory assessment of the lighting, acoustics, and air conditioning quality. The data will be used as a decision supporting system (DSS) by building management through the use of a GUI. The design of the interface was based on a survey result from the prospective users. Installed energy monitoring system uses a current sensor with an accuracy of 98% and a precision of 0.04 A while the voltage sensor with an accuracy of 98% and a precision of 0.58 V. The performance testing shows that the number of web clients influences delay of data transmission. The result of the survey shows that GUI is categorized as fair in design without a significant difference between the perceptions of users with and without survey supervision.

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