Low Electrical Energy Research Articles

Molecular dynamics analysis for aggregation phenomenon of aged asphalt and depolymerisation mechanism of regenerants

ABSTRACT The depolymerisation mechanism of various regenerants, when applied to the aged asphalt aggregate structure, was investigated to provide insights for the design and development of regenerants. This study focused on the molecular aggregation of the regenerant-aged asphalt system using molecular dynamics simulation technology. Simulation showcased that the uneven charge distribution in asphaltene molecules and the absence of charge in the central region are prerequisites for the electrostatic attraction of asphaltene molecules, which significantly affects their aggregation, and asphaltene molecules in heavy-aged asphalt are prone to forming stable aggregation structures. Among the four components of aged asphalt, asphaltene molecules exhibited the most significant self-aggregation, followed by saturates, while resin and aromatic molecules showed relatively weaker self-aggregation. Low temperatures encouraged aggregation, whereas high temperatures discouraged it, and ageing elevated the molecular self-aggregation, intensifying with the progression of asphalt ageing. Regenerants improved the depolymerisation of asphaltene aggregates, and fatty acid glycerides presented the most effective depolymerisation, followed by aromatic hydrocarbons and alkanes, while glycerol’s performance was the least effective. To choose regenerant composition materials, those with low electrical potential energy, weak polarity, low polar functional group content or non-polarity should be selected to ensure superior depolymerisation, permeation fusion, and regeneration effects.

Synergistic effects of a sequential recirculation electrochemical system combined with low-cost UV-LEDs on the gram-negative bacteria inactivation

In this work, an electrochemical system combined with low-cost UV-LEDs was implemented for the inactivation of Escherichia coli and Pseudomonas aeruginosa. The individual elimination of these bacteria was followed by plate counting and flow cytometry, as complementary techniques to establish the cell inactivation and non-viability, respectively. The contribution of the different parts of the disinfection system (anode, cathode, and light) was determined. In addition, the efficiency of the UV-LEDs/GDE/DSA system in the disinfection of an irrigation water sample was studied. It was found that the combination of the electrochemical system with UV-LEDs was highly synergistic (φ > 7), having low electric energy consumptions per order of magnitude (EEO: 1.13 × 10–2 and 1.55 × 10–2 kWh/m3 order). Moreover, some differences in the inactivation kinetics and synergy between E. coli and P. aeruginosa were observed and linked to the structural/morphological characteristics of the two bacteria. Remarkably, the electrochemical system combined with low-cost UV-LEDs inactivated both target microorganisms after only 2 min of treatment. The flow cytometry analyses evidenced the damage to the cell membrane of the bacteria by the simultaneous and synergistic action of the electrogenerated H2O2 and active chlorine species (ACS), plus the attacks of photo-generated reactive oxygen species. This synergistic combination in the UV-LEDs/GDE/DSA system demonstrated remarkable efficiency in the disinfection of an irrigation water sample, achieving the elimination of culturable bacteria in 45 min of treatment. The results of this research demonstrated the capacity and great potential of an easy combination of electrochemistry with UV-LEDs as an alternative system for the elimination of gram-negative bacteria in water.

Efficient degradation of ciprofloxacin by innovative VUV/BN system: Kinetics, mechanism and toxicity assessment

Given the increasing emergence of widespread fluoroquinolones (FQs) in natural water environments and the limitations of traditional vacuum ultraviolet (VUV) systems for water decontamination, an innovative VUV/BN system was developed for the degradation and detoxification of ciprofloxacin (CIP) in this work. Unlike the VUV system, which primarily relies on hydroxyl radicals (·OH), the VUV/BN system significantly enhances the concentration of singlet molecular oxygen (1O2) to target the piperazine ring of CIP, achieving a defluorination efficiency of 98.88 % within 60 min. The degradation rate constant for CIP was found to be 2.76 times greater than that of the traditional VUV system. Additionally, varying concentrations of reactive species (RSs) in the VUV and VUV/BN systems resulted in distinct CIP degradation pathways. Due to the high selective oxidation capacity and environmental compatibility of 1O2, the VUV/BN system demonstrated excellent adaptability to environmental factors, maintaining stable operation in complex water matrices. Furthermore, the system exhibited high degradation capacity for CIP even in the fifth cycle, confirming its exceptional stability and reusability. The economic feasibility of the VUV/BN system was confirmed by its low electrical energy per order (EEO). This study underscores the potential of VUV/BN systems and enhances the understanding of CIP photodegradation.

Preparation of two–dimensional gradient fillers reinforced polymer nanocomposites for high–performance energy storage of dielectric capacitors

The serious interfacial issue between the inorganic filler and the organic matrix in the dielectric nanocomposite results in a low electric field breakdown strength (Eb) and low energy density (Ue). In this work, novel KxNa1–xNbO3@ZrO2 (KNN@ZO) nanosheets (NSs) were prepared by coating highly insulated ZO on the ferroelectric two–dimensional (2D) KNN NSs via a chemical precipitation method. As fillers, the KNN@ZO significantly improved the energy storage performances of poly (vinylidene fluoride) (PVDF)–polymethyl methacrylate (PMMA) blends. The highly insulated ZO shell restricts the carrier migration at the filler/polymer interface, thereby reducing the local electric field distortion. By sandwich structural design, a high Ue of 19.8 J/cm3, with a large difference of electrical displacement (8.5 μC/cm2), is measured in KNN@ZO/PVDF–PMMA with 5 % filler content at 528 MV/m. According to the finite element simulation, the 2D morphology and gradient structure can enhance the electric field distribution, and therefore effectively increase the Eb of nanocomposites. The results indicate that the 2D core–shell NSs fillers with gradient dielectric constant represent an effective approach to improve energy storage performance of the polymer–based nanocomposites.

In-situ fabrication of defect rich Cu2+1O on electrodeposited Cu cone arrays for promoting electrocatalytic anode hydrogen production

The low-potential formaldehyde oxidation reaction (FOR) is a significant replacement for oxygen evolution reaction, as FOR can couple with the cathode hydrogen evolution reaction (HER) to obtain a bipolar H2 production system with an extra low cell voltage. Cu-based electrocatalysts offer cost advantages in FOR but suffer from poor intrinsic activity and stability. Herein, a novel defect rich CF-Cu@Cu2+1O/Cu pinecone-shaped array electrocatalyst is fabricated by in-situ solution immersion of electrodeposited Cu cone arrays on foam for efficient and stable formaldehyde selective oxidation reaction to co-produce hydrogen and valuable formate. Benefitting from the partially mixed Cu2+1O in metallic copper and concomitant production of defect rich oxygen vacancies, only 0.04 VRHE is required for electrocatalytic FOR at 100 mA·cm−2 under alkaline conditions. FOR current density of CF-Cu@Cu2+1O/Cu electrode exhibits 2.35 times than that of CF-Cu (144 mA·cm−2) and 77 times than that of copper foam (4.4 mA·cm−2) at 0.5 VRHE. Moreover, the special pinecone-shaped structure is constructed to modify Cu-based catalysts with substantially enhanced stability. A FOR-HER co-electrolysis device of CF-Cu@Cu2+1O/Cu(+)||Pt/C(−) can achieve bipolar H2 production with an approaching 200 % Faradaic efficiency, requiring an extremely low electrical energy consumption of only ∼ 0.35 kWh per m3 of H2 and potential of 0.291 V at 100 mA·cm−2 at room temperature.

Phase‐Transition Photonic Brick for Reconfigurable Topological Pathways

AbstractTopological photonic insulators serve as highways for light propagation, enabling photons to be transported with topological protection and enriching the understanding of light‐matter interactions. However, the prohibitive fabrication and non‐reconfigurable functionality of current topological photonics seriously hinder its practical applications. Here, a revolutionary concept of phase‐transition photonic brick is theoretically proposed and experimentally demonstrated, which can be regarded as an ideal building block to develop reconfigurable highways for light propagations. The proposed modular photonic brick not only integrates the inherent benefits of both passive and active topological photonics, but also offers previously unattainable superiority, including flexible scalability, deformability, detachability, and recyclability. Leveraging these benefits, this work provides a groundbreaking topological platform that balances the reconfigurability, multifunctionality, low electrical energy consumption, and low device fabrication cost. By unlocking the potential of recyclable photonic bricks, the work represents a significant step toward realizing the extensive and sustainable practical applications of topological photonics in information processing, computing, communications, and beyond.

Enhancing electrochemical carbon dioxide capture with supercapacitors

Supercapacitors are emerging as energy-efficient and robust devices for electrochemical CO2 capture. However, the impacts of electrode structure and charging protocols on CO2 capture performance remain unclear. Therefore, this study develops structure-property-performance correlations for supercapacitor electrodes at different charging conditions. We find that electrodes with large surface areas and low oxygen functionalization generally perform best, while a combination of micro- and mesopores is important to achieve fast CO2 capture rates. With these structural features and tunable charging protocols, YP80F activated carbon electrodes show the best CO2 capture performance with a capture rate of 350 mmolCO2 kg–1 h–1 and a low electrical energy consumption of 18 kJ molCO2–1 at 300 mA g–1 under CO2, together with a long lifetime over 12000 cycles at 150 mA g–1 under CO2 and excellent CO2 selectivity over N2 and O2. Operated in a “positive charging mode”, the system achieves excellent electrochemical reversibility with Coulombic efficiencies over 99.8% in the presence of approximately 15% O2, alongside stable cycling performance over 1000 cycles. This study paves the way for improved supercapacitor electrodes and charging protocols for electrochemical CO2 capture.

Synergic treatment of domestic wastewater and food waste in an anaerobic membrane bioreactor demo plant: Process performance, energy consumption, and greenhouse gas emissions

Ambient operation and large-scale demonstration have limited the implementation and evaluation of anaerobic membrane bioreactors (AnMBRs) for low-strength wastewater treatment. Here, we studied these issues at an AnMBR demo plant that treats domestic wastewater and food waste together at ambient temperatures (7–28 °C). At varied hydraulic retention times (HRTs, 8–42 h), the AnMBR achieved a COD removal efficiency and biogas production of 80.4% ± 3.9% and 66.5 ± 9.4 NL/m3-Influent, respectively. Moreover, a stable high membrane flux of 14.4 L/m2/h was reached. The electric energy consumption for the AnMBR operation was 0.269–0.433 kW·h/m3, and 49.4%–91.3% could be compensated by the electric energy produced from methane production. At an HRT of 10 h, the AnMBR system demonstrated an impressively low net electric energy consumption of merely 0.05 kW·h/m3, resulting in a net greenhouse gas emission of 0.015 CO2-eq/m3, cutting 85% compared to the conventional activated sludge process. Achievements in this study provide key parameters for the ambient operation of AnMBR and demonstrate that AnMBR is an energy-saving and low-carbon solution for low-strength wastewater treatment.

Microwave-induced dual-responsive spinel (CoxMn1-xFe2O4) target-triggered non-radical pathways of peroxymonosulfate: Superexchange interaction and synergistic mechanism

The efficient activation of peroxymonosulfate (PMS) and the directional selection of oxidation pathways are crucial for achieving efficient pollutant removal in advanced oxidation processes (AOPs). A composite activation method of a microwave-induced dual-responsive catalyst (Co0.4Mn0.6Fe2O4) with both dielectric and catalytic properties is proposed to successfully trigger the non-radical pathway of PMS for 100 % removal of pharmaceutical pollutant (diatrizoate, DTZ) in 6 min, which shows good resistance to environmental interference and cyclic stability, and lower electrical energy requirement. 1O2 and surface-bound reactive oxygen species (ROS) are the main ROSs responsible for non-radical oxidation, with a total contribution of 98 %. The superexchange effect of Co-Mn (Mn3++Co3+→Mn4++Co2+) induces the electron delocalization of Mn site, which promotes the adsorption of PMS, interfacial charge transfer, and surface-bound ROS generation. The "thermal and non-thermal" effects of microwaves accelerate electron transfer and 1O2 generation to further trigger non-radical pathways. This work provides new strategies for bifunctional catalyst design and directional triggering of non-radical pathways of PMS-AOPs.

Dynamic-based artificial intelligence model for simulation and optimization of the single chamber anode brush microbial electrolysis cell

Microbial electrolysis cells (MECs) have become more attractive because they can produce hydrogen (H2) from various organic sources with a low input electrical energy requirement. In this study, a dynamic model for the single-chamber anode brush MEC with acetic acid as a carbon source was developed for the first time. The dynamic model was calibrated and validated using both experimental and literature data, with a high coefficient of determination (R2) of 0.87–0.99, a high Pearson correlation coefficient (PCC) of 0.93–0.99, and a low normalized root mean squared error (NRMSE) of 0.221–0.078. For rapid simulation and optimization, the validated dynamic model was reproduced using an artificial neural network (ANN), and particle swarm optimization (PSO) was then applied to optimize the fitness functions derived from this ANN model (i.e., hydrogen production yield, hydrogen production rate, hydrogen fraction in biogas, and total energy recovery). As a result, the proposed method took about 3 s with an absolute error of <3.5 %. The optimization results revealed that an optimal condition (including applied voltage, operating temperature, substrate concentration, and reactor working volume) cannot exist to obtain the maximum values of all performance parameters simultaneously. Under the same importance, the co-optimal condition was determined at an applied voltage of 0.9 V, temperature of 36.2 °C, substrate concentration of 0.87 g/L, and reactor working volume of 0.05 L. At such co-optimal conditions, MEC achieved an H2 yield of 1168.6 ± 13.3 mL/g with a production rate of 185.6 ± 2.7 mL/L/h, an H2 fraction of 63.6 ± 0.2 %, and a total energy recovery (including electrical, substrate, heat, and mixing input energies) of 16.7 ± 0.2 %. Although these performances increased 1.5–2.3 times compared to non-optimal conditions, the low energy efficiency indicates the need for further investigation into combining MEC with sustainable energy sources, such as solar, wind and osmosis.

Enhancement of Biogas (Methane) Production from Cow Dung Using a Microbial Electrochemical Cell and Molecular Characterization of Isolated Methanogenic Bacteria

Biogas has long been used as a household cooking fuel in many tropical counties, and it has the potential to be a significant energy source beyond household cooking fuel. In this study, we describe the use of low electrical energy input in an anaerobic digestion process using a microbial electrochemical cell (MEC) to promote methane content in biogas at 18, 28, and 37 °C. Although the maximum amount of biogas production was at 37 °C (25 cm3), biogas could be effectively produced at lower temperatures, i.e., 18 (13 cm3) and 28 °C (19 cm3), with an external 2 V power input. The biogas production of 13 cm3 obtained at 18 °C was ~65-fold higher than the biogas produced without an external power supply (0.2 cm3). This was further enhanced by 23% using carbon-nanotubes-treated (CNT) graphite electrodes. This suggests that the MEC can be operated at as low as 18 °C and still produce significant amounts of biogas. The share of CH4 in biogas produced in the controls was 30%, whereas the biogas produced in an MEC had 80% CH4. The MEC effectively reduced COD to 42%, whereas it consumed 98% of reducing sugars. Accordingly, it is a suitable method for waste/manure treatment. Molecular characterization using 16s rRNA sequencing confirmed the presence of methanogenic bacteria, viz., Serratia liquefaciens and Zoballella taiwanensis, in the inoculum used for the fermentation. Consistent with recent studies, we believe that electromethanogenesis will play a significant role in the production of value-added products and improve the management of waste by converting it to energy.

The Enhancement of Tumor Ablation Effect by the Combination of High-Frequency and Low-Voltage Bipolar Electroporation Pulses.

Recently, combining short high-voltage IRE monopolar pulses with long low-voltage IRE monopolar pulses was shown to enlarge the ablation region. This finding indicates that combining HFBPs with low-voltage bipolar pulses (LVBPs), which are called composited bipolar pulses (CBPs), may enhance the ablation effect. This study designed a pulse generator by modifying a full-bridge inverter. The cell suspension and 3D tumor mimic experiments (U251 cells) were performed to examine the enhancement of the ablation effect. The generator outputs HFBPs with 0-±2.5 kV and LVBPs with 0-±0.3 kV in one period. The pulse parameters are adjustable by programming on a human-computer interface. The cell suspension experiments showed that CBPs could enhance cytotoxicity, as compared to HFBPs with no cell-killing effect. Even at lower electric energy, the cell viability by CBPs was significantly lower than that of the HFBPs protocol. The ablation experiments on the 3D tumor mimic showed that the CBPs could create a larger connected ablation area. In contrast, the HFBPs protocol with a similar dose generated a nonconnected ablation area. Results indicate that the CBPs protocol can enhance the ablation effect of HFBPs protocol. This proposed generator that uses the CBPs principle may be a useful tool for tumor ablation.

Small-scale industrial hydrogen liquefaction and refrigeration

As the hydrogen economy expands, the need for point of use production with smaller liquid hydrogen (LH2) production capacities will increase. Examples of this are transportation hubs in remote locations and numerous other applications where the required LH2 production is less than 5 MT/day. In response to this need, a small-scale industrial 1,000 kg/day hydrogen liquefaction plant is being developed and is planned for operation in 2024. The plant will achieve localized, efficient production, on-demand, in remote locations or any location advantageous for use in transportation, where complicated logistics, with associated transportation costs and tanker evaporative losses are eliminated or minimized. The chief advantages of the design are small size/footprint, safety, reliability, low cost, lack of restrictions on site location, and ability to make practical use of renewable energy. The liquefaction plant utilizes a closed-loop helium reverse-Brayton cycle refrigerator where refrigerant temperatures significantly less than the hydrogen liquefaction temperature cause the hydrogen gas stream to be liquefied. The liquefied hydrogen is maintained in the liquid state via a helium side stream taken from the refrigeration loop routed through the LH2 storage tank. This optional system can maintain LH2 temperatures in the storage tank lower than 18 K to eliminate boiloff and facilitate zero loss transload from tanker trucks and eliminate losses in transfer/dispensing. The hydrogen liquefaction plant does not require liquid nitrogen (LN2) pre-cooling and so can be located in remote areas wherever there is 480 V electricity and hydrogen production capacity available. A slightly modified reverse-Brayton cycle is also used in the refrigeration/storage plants. These plants can facilitate zero loss tanker transload and zero boiloff for LH2 storage plants of virtually any capacity. The smallest of these reverse-Brayton cycle refrigerators, currently in detailed design, refrigeration system RS1500 (1000 W heat lift @ 20K) will be capable of eliminating boiloff losses of the largest storage tanks currently in operation with very low electrical energy consumption.

Analysis of the Operating Energy Variables Involved in Mechanized Khoa Production

Significant portion of the total milk production of India has been utilized for the manufacture of the Traditional Indian Dairy Products (TIDP). Khoa based products were traditionally produced in the Indian sub-continent since ancient times. Khoa produced by the mechanized methods can overcome the demerits of traditional manufacturing methods like insufficient use of energy, poor hygiene and sanitation, non-uniform product quality, etc. In the present study, steam jacketed open type hemispherical kettle equipped with spring loaded Teflon edged scraper blade assembly was utilized for the mechanized production of khoa. A standardized mixed milk having (6.0±0.1%) fat and (9.0±0.2%) SNF, was evaporated to the different level of concentration using a batch type vacuum pan. The performance of the mechanized manufacture of khoa was evaluated at different steam pressures (P1= 98.06 kPa, P2=147.1 kPa, P3=171.61 kPa), scraper speed (R1=0.67rps), and different level of milk concentration (C1=35 %TS, C2=40 %TS, C3=45 %TS) for first stage. During the second stage, effect of operating variables on process mechanization were evaluated at different steam pressures (S1= 49.03 kPa and S2= 78.45 kPa) and scraper speed (R2=0.33rps). The primary objective of present study is to carry out thermal and electrical energy analysis associated with mechanized khoa production, which has a significant role in process optimization, scale-up of the operation and to design and fabricate the mechanized system. The overall heat transfer coefficients (U-values) of the mechanized system obtained at various processing parameters ranged from 156.87 to 234.16 W/m2K during khoa manufacturing. The treatment C1 P1 S2 gave the highest U-values for sensible and latent heating. The mean U-values of sensible heating and latent heating were increased with an increase in steam pressure during khoa making in the mechanized system. The mean value of specific steam consumption (kg steam/kg water evaporated) for the optimized operating conditions was 1.950 (kg steam/kg water evaporated) for manufacture of khoa in mechanized system. The total heat losses of mechanized system during manufacture of khoa was 17.15 to 28.02 % at different operating conditions studied. The mean values of electrical power consumption ranged from 141 to 203 Wh under different operating conditions. Considering the energy consumption data, we can narrate that existing system is energy efficient with lower electrical energy consumption and can reduce the labour cost due to mechanization.

Rapid inactivation of antibiotic resistance genes and virulence genes in the building ventilation duct by UV185+254 irradiation

The energy-efficient inactivation of airborne antibiotic resistance genes (ARGs) and virulence genes was seldom investigated in full-scale ventilation systems. This study examined the potential of UV disinfection to inactivate two types of chromosome- or plasmid-encoded ARGs (mecA and amp) and one chromosomal virulence gene (tst1) within two host bacterial species: Staphylococcus aureus and Escherichia coli. UV185+254 disinfection exhibited dual damages (i.e., physical by 254 nm UV and oxidative by the produced ozone) on those target genes, resulting in relatively strong adaptability to temperature and low electrical energy per order in specific gene removal (down to 1 kJ m−3). It was found that the disinfection efficiency of target genes was up to 2 orders of magnitude lower than that of the host bacteria. The target genes with more bases and higher weighted bipyrimidine content were more susceptible to UV185+254 treatment. Thicker cell walls and plasmid carriers prominently hindered UV185+254 deactivation, requiring larger radiation power to enhance the gene removal efficiency in bioaerosols.

Superior electric displacement and energy storage density in dielectric polymer via inserting thermoplastic polyurethane

Dielectric polymers have been broadly applied in film energy storage capacitors owing to their excellent insulating characteristics. However, low electric displacement (D) and available energy densities (Ue) of existing polymer systems restrict them for miniaturized and integration applications. Herein, thermoplastic polyurethane (TPU) is utilized as the central layer to provide high D, and poly (methyl methacrylate) (PMMA) is used as the coating layer to maintain insulating characteristics. The electric displacement difference (Dmax-Dr) value and Ue values of the all-organic composites were optimized by modifying the relative ratios of the intermediate layer TPU. Notably, the all-organic composites with optimized relative ratio (26.13 vol%) of the TPU layer exhibits the largest Dmax-Dr of 8.27 μC/cm2 at highest breakdown strength of 450 MV/m, which is 89 % higher than that of PMMA at 4.37 μC/cm2, and thus a maximum Ue of 16.23 J/cm3 is obtained, far exceeding the values for advanced polymer and their composites. This strategy provides an effective approach for the development of dielectric polymer with high energy storage capabilities.

Surface and quantum chemical parameters of nickel oxide nanostructures suited for ultraviolet-assisted cationic dye degradation

Nickel oxide (NiO) nanostructures were synthesized through chemical precipitation and subsequently analyzed using a scanning electron microscopy (SEM) and X-ray diffraction (XRD). Rietveld refinement of XRD data revealed a cubic structure with lattice parameters of a = b = c = 4.173 Å. Fourier transform infrared spectroscopy and energy dispersive X-ray were employed to analyze the functional group and elemental composition of NiO NPs. The ultraviolet diffuse reflectance spectra indicated an optical band gap of 3.08 eV for synthesized NiO nanoparticles. Surface characteristics were evaluated using the Gwyddion open-source application, and parameters including Ra (mean roughness), Rq (mean square roughness), Rsk (surface skewness), and Rku (kurtosis coefficient) were calculated. The chemical properties of NiO were investigated through density functional theory calculations, and the results aligned well with experimental data. Furthermore, a comparative analysis of the photodegradation of methylene blue (MB) and rhodamine B (RhB) in the presence of UV light was examined, and it followed pseudo-first-order rate kinetics with degradation efficiencies of 82.62% (MB) and 71.31% (RhB), respectively. The electric energy per order for the photodegradation process was calculated to be 9.4 × 102 kWh/m3/order (MB) and 11.7 × 102 kWh/m3/order (RhB). Notably, the low electric energy consumption per order indicated a cost advantage for the reactor setup.

Controllable Pyridine N-Oxidation-Nucleophilic Dechlorination Process for Enhanced Dechlorination of Chloropyridines: The Cooperation of HCO4- and HO2.

Dechlorination of chloropyridines can eliminate their detrimental environmental effects. However, traditional dechlorination technology cannot efficiently break the C-Cl bond of chloropyridines, which is restricted by the uncontrollable nonselective species. Hence, we propose the carbonate species-activated hydrogen peroxide (carbonate species/H2O2) process wherein the selective oxidant (peroxymonocarbonate ion, HCO4-) and selective reductant (hydroperoxide anion, HO2-) controllably coexist by manipulation of reaction pH. Taking 2-chloropyridine (Cl-Py) as an example, HCO4- first induces Cl-Py into pyridine N-oxidation intermediates, which then suffer from the nucleophilic dechlorination by HO2-. The obtained dechlorination efficiencies in the carbonate species/H2O2 process (32.5-84.5%) based on the cooperation of HCO4- and HO2- are significantly higher than those in the HO2--mediated sodium hydroxide/hydrogen peroxide process (0-43.8%). Theoretical calculations confirm that pyridine N-oxidation of Cl-Py can effectively lower the energy barrier of the dechlorination process. Moreover, the carbonate species/H2O2 process exhibits superior anti-interference performance and low electric energy consumption. Furthermore, Cl-Py is completely detoxified via the carbonate species/H2O2 process. More importantly, the carbonate species/H2O2 process is applicable for efficient dehalogenation of halogenated pyridines and pyrazines. This work offers a simple and useful strategy to enhance the dehalogenation efficiency of halogenated organics and sheds new insights into the application of the carbonate species/H2O2 process in practical environmental remediation.

Analysis PM2.5 Removal Efficiency and Electrical Energy Consumption in The Use of Air Purifier and Air Conditioner in a Room

Indoor air quality is important for an individual's quality of life because humans often spend 90% of their time indoors. Indoor air quality impacts human comfort, health, and performance. This research aims to identify the effect of variations in AC temperature control systems and air purifier fan speed on PM2.5 concentrations, as well as indoor thermal comfort and recommendations for AC and AP settings to remove PM2.5 with high efficiency and lower electrical energy with statistical tests. The highest percentage of PM2.5 removal when the AC was set to a temperature of 22°C with the AP turned on automatically, namely 89.7% in removing PM2.5. The lowest percentage of removal of PM2.5 concentrations when the AC temperature was set to be turned on at 25°C with the AP set turned off, namely 40.57%. The first recommendation is to set the AC to be turned on at 25°C and the AP to be turned on automatically, which has a percentage of 84.72% with a monthly price of 17,400 IDR. The second condition that can be recommended is setting the AP to be turned on automatically, but the AC set turned off, which has a percentage of 88.34% for 1,800 IDR.

Analysis of Aerosol Removal Efficiency and Electrical Energy Consumption in the Use of Air Conditioner and Air Purifier in a Room

Analysis of Aerosol Removal Efficiency and Electrical Energy Consumption in the Use of Air Conditioner and Air Purifier in a Room