Electric Intensity Research Articles

Aerosol Impacts on Storm Electrification and Lightning Discharges Under Different Thermodynamic Environments

AbstractThe impacts of aerosol and thermodynamics on electrification and lightning activities have been investigated in detail using the Weather Research and Forecasting Model coupled with a double‐moment microphysics parameterization and an explicit electrification lightning scheme. To obtain a varied combination of convective available potential energy (CAPE) values and aerosol concentrations, a sounding was modified consistently and initiated with five sets of aerosol concentrations that served as cloud condensation nuclei. The simulated electric processes respond to the varying dynamical and microphysical characteristics associated with the different CAPE and aerosol conditions. Under high CAPE circumstances, the augmentation of ice‐phase particle leads to the enhancement of non‐inductive charging primarily through the dynamic processes. Increased aerosol content further invigorates the electrification through microphysical processes. Elevated aerosol loading under low CAPE conditions increases cloud droplet and ice crystal numbers. Larger graupel particle size further leads to the enhanced electric intensity and lightning discharges.

Characterization and synthesis mechanism of Co3O4 nanoparticles synthesized by the emulsion detonation method

Tricobalt tetraoxide (Co3O4) nanoparticles have excellent applications in the fields of electricity, photocatalysis, and ceramics, whereas conventional synthesis methods require sophisticated equipment, strictly controlled conditions, and long duration. Herein, a new method for the synthesis of Co3O4 nanoparticles was proposed. In this emulsion detonation method, the precursor cobalt nitrate hexahydrate (Co(NO3)2·6H2O) was added during the production of the explosives and was therefore more uniformly dispersed than in other detonation methods. The preparation and detonation durations of the explosives were on the scale of minutes and microseconds, respectively, which are much shorter than those in other nanomaterial synthesis methods. The collected products were briefly purified and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometer, field emission scanning electron microscopy, and field emission transmission electron microscopy. Cyclic voltammetry and galvanostatic charge–discharge measurements were performed. The results show that the synthesized products were of high purity and consisted mainly of sphere-like particles with a dimensional distribution of approximately 50 nm. The electrochemical properties of these Co3O4 nanoparticles were similar to those synthesized by conventional methods. Combined with the detonation theory and the initial composition of the products, the analysis showed that the synthesis mechanism is mainly divided into two stages: formation and polymerization. Therefore, this approach could provide a new and effective synthesis method for the low-cost production of Co3O4 nanoparticles.

ІНСТИТУЦІЙНЕ СЕРЕДОВИЩЕ ФІНАНСОВОГО ЗАБЕЗПЕЧЕННЯ СТАЛОГО РОЗВИТКУ ЕЛЕКТРОЕНЕРГЕТИЧНИХ КОМПАНІЙ

The article is devoted to the disclosure of issues, conditions, structures and directions for improving the institutional environment of financial support for the development of the energy sector. The aim of the research: is to determine directions for improving the institutional environment of financial support for the sustainable development of electric power companies under the conditions of implementing financial decisions regarding the attraction and effective use of financial resources and state financial support within the framework of the implementation of national priorities for the development of the electric power industry. The subject of the research: institutional environment and its impact on financial support for the sustainable development of electric power companies. The methods of the research: of scientific knowledge, method of generalization, comparison, logical – meaningful, methods of induction and deduction. The main hypothesis of the study is the assumption that the influence of the institutional environment on the financing of the sustainable development of electric power companies is manifested through legal support, state support (regulation, control, audit of restoration processes) of projects, the development of risk insurance mechanisms, the implementation of methods of optimal allocation of resources according to the priority of restoration programs , deepening the interaction of state institutions with electric power companies on the basis of public-private partnership. The statement of basic materials. On the basis of the analysis of the institutional environment and regulatory and legal support for the activity of energy enterprises, the problematic field of institutional issues in the field of state regulation of the activities of the subjects of the electric energy market and directions for their solution have been determined. The essence of the institutional environment is determined and its influence on financial support for the sustainable development of energy enterprises is demonstrated. The role of financial institutions in ensuring the sustainable development of public companies is shown. Based on the analysis of the state of financial support for the development of the energy sector of Ukraine, it was established that financial and credit institutions have a limited influence on the formation of financial resources of enterprises in the energy sector. Attention is focused on the need to implement international experience in financing the sustainable development of energy enterprises. The institutional conditions for financial support for the development of electric power companies are disclosed and restraining factors regarding the attraction of investment resources are identified. The characteristics of financing tools for the sustainable development of energy sector enterprises are given. It is proved that the institutional environment of market relations is directly a lever of influence on the reproductive processes of capital formation of energy enterprises. The directions for improving regulatory legislation, the state policy of financing the development of the energy sector in the context of the selection of mechanisms for stimulating the development of the electric power sector, including RES, and supporting the development of new technologies are substantiated; use of world experience. The originality and practical significance of the research: have proposals regarding the use of financing tools for the sustainable development of energy sector enterprises and the determination of directions for improving the state financing policy in the context of choosing mechanisms for stimulating the development of the electricity sector. Conclusions and perspectives of further research: The institutional influence on financial support for the development of the energy sector is manifested through: improvement of regulatory legislation in the context of creating favorable conditions for supporting the decarbonization of the Ukrainian economy and the post-war recovery of energy enterprises; state financial support for stimulating the participation of banks in the post-war restoration of ecological technologies, increasing the share of RES generation in the Ukrainian energy system; the development of mechanisms for the removal of tax restrictions (in particular, regarding gas rent and the ban on imports) and the creation of mechanisms for guaranteeing military risks; implementation of methods of optimal distribution of resources according to post-war reconstruction programs, taking into account their priority and strengthening of financial control, transparency regarding targeted use; creation of favorable conditions for lending, taking into account world practices. In order to achieve ecologically safe, socially oriented economic development, it is expedient to apply world experience and effective methods and forms of mobilization of financial resources in the field of electricity.

Financial, Economic, and Environmental Analyses of Upgrading Reverse Osmosis Plant Fed with Treated Wastewater

One of the most effective strategies to mitigate water shortages worldwide is to reuse treated wastewater for freshwater production employing reverse osmosis (RO) technology. This strategy is appropriate in urban areas of arid or semi-arid regions as it can provide a sustainable and reliable water source close to the consumers. One of the drawbacks of RO is the high variability of production costs due to the electricity intensity. In addition, depending on the electricity source, it can also result in substantial environmental costs. This study showed that upgrading pumping and RO membrane systems of a wastewater reuse plant in Cyprus can significantly alleviate these drawbacks in terms cost, water recovery rate, and air pollution. The water-recovery rate of the upgraded RO plant increased from 43.2 to 75 percent, which resulted in a substantial net financial benefit due to the reduction in the quantity of wastewater purchased and the increase in potable water produced. The upgraded system also reduced the electricity requirement from 3.63 kWh/m3 to 1.92 kWh/m3. Pollution emissions decreased substantially because of the reduction in electricity requirements. The beneficiaries of these lower emission costs are the residents of Cyprus and global society. Overall, the benefit of upgrading the plant is highly attractive with more than 65 percent annual real internal rates of return in financial and economic terms. Positive net present values are realized for all the scenarios considered.

Unsteady electrorotation of a viscous drop in a uniform electric field

A dielectric drop suspended in an immiscible dielectric fluid of higher conductivity can spontaneously generate the so-called Quincke rotation (a rotating activity that a weakly conducting drop/solid particle displays in an electric field) subjected to sufficiently strong electric field strength. The steady tilt has been extensively studied and is well elucidated now. However, the unsteady electrorotation of drop remains a largely unclear, complex issue. Motivated by this, we examine the unsteady drop electrorotation in this work with the required integrated convective bulk charge transport effect. First, for the steady rotation, the transient evolution to a steady droplet tilt from the symmetric Taylor state is analyzed in-depth. Here we discover several new phenomena, including the evolving equatorial charge jets. For unsteady rotation, based on a drop's interfacial charge variation, deformation, and tilt angle, the study reports the growth of three distinct rotating patterns in the viscosity ratio range 0.2≤λ=μi/μo≤20.0 and electric field strength E0≤25 kv/cm at a fixed conductivity ratio Q ( = σi/σo) = 0.026 and permittivity ratio S (= ϵi/ϵo) = 0.566. A low-viscosity drop ( λ≤2.5) exhibits only the periodic rotation. For the viscosity ratio 2.5<λ<7.0, the increased electric intensity creates two new unsteady rotation modes: the pseudo-periodic tumbling and the irregular one. For λ≥7, the periodic mode remains absent; instead, the drop displays the electric intensity-dependent tumbling and irregular rotation patterns. Our study shows that the rotation reduces a drop's transitory interfacial charge. At this stage, the drop rotation behavior is controlled by competing charge convection due to fluid flow and charge supply by conduction. The resulting varying electric Reynolds number ReE (the time ratio of charge relaxation and charge convection) explains the created different rotation mechanisms. For ReE>1, owing to lacking enough interfacial charge to sustain rotation, the drop's transition to a temporary non-rotating Taylor state occurs until the interface recharges. The resultant mechanism supports the periodic batch-type rotation for a low-viscosity drop and the irregular rotation for a high-viscosity drop in a higher electric field. In contrast, for ReE<1, the drop timely acquires sufficient charge to support continuous tumbling electrorotation.

The partial electrical breakdown mechanism by high voltage electric pulses in multi-fractured granite

High-voltage electric pulse (HVEP) technology has currently become a new efficient rock breaking method. In order to reveal the influence of internal fracture characteristics of heterogeneous granite on electric pulse rock breaking, the two-dimensional numerical model of multi-physical field coupling electrical breakdown of fractured rock is established, which the high-voltage electric pulse plasma generation in multi-fractured heterogeneous granite is realized from the coupling of circuit field, current field, breakdown field, heat transfer field and solid mechanics. This paper analyzes the influence of fracture porosity, fracture types and granite heterogeneity on the electrical breakdown of rock (i.e. the formation of plasma channel inside the rock). At the same time, the two-dimensional numerical model of electrical breakdown parameters, which considers the circuit structure parameters of the pulsed tool, the initiation and development of the electrical breakdown, the dependence between electrical breakdown intensity and time, and rock heterogeneity, are analyzed. The simulation results indicate that with the heterogeneity H of granite changing, the plasma channel inside the rock samples are different, while the time required for breakdown t and rock breaking volume Vrock of rock samples with different heterogeneous H will show obvious fluctuations; among the rock samples with different heterogeneity H, existing a single crack requires a longer breakdown time and the extreme value of the internal conductivity is also significantly larger. And then, the formation of plasma channel is directional selective, extending towards fractures and the weak electrical breakdown intensity. With the dip angle of the fracture increasing, the required breakdown time increases accordingly, and conversely, the broken volume decreases accordingly. The larger porosity of fracture is, the larger broken volume and the shorter required break down time of the rock sample. Furthermore, with the continuous action of electric pulses, multi-fractured rock form interpenetrating plasma channels to improve the rock breaking efficiency. The research results can provide help and theoretical support for optimization of electric pulse rock breaking parameters and the development of electric pulse drilling technology.

Elucidating the alkene hydrogenation reaction based on cotton textile reduced graphene oxide under the influence of external electric field: Illustration of new noble method

The hydrogenation reaction of alkene is one of the most used industrial chemical process for various materials of daily life and energy consumption. This is a heterogeneous reaction and traditionally carried out by metallic catalysis. However, these conventional catalytic hydrogenations of alkene suffer from various setbacks such as catalyst poisoning, less recyclability and are environmentally unfriendly. Therefore, in recent years, researchers have been trying to develop the alternatives to metal catalysis hydrogenation of alkene. Heterogeneous catalysis under the external electric field is considered the future of green catalysis. In this paper, we report a comprehensive investigation dealing with the theoretical basis for simulating the phenomenon of heterogeneous catalysis, on a molecular level, under an external electric field. The illustration of the prospect as well as the effects of the mostly used catalytic systems, reduced graphene oxide, under the influence of external electric fields is provided. Moreover, a noble method of alkene hydrogenation reaction based on cotton textile reduced graphene oxide (CT-RGO) under the influence of an external electric field is introduced. The corresponding theoretical investigation was carried out within the framework of the density functional theory (DFT) method using first-principles calculations. The study has been carried out by elucidating DFT calculations for three different proposed catalytic systems, namely without electricity, with electricity and with an external electric field of 2 milli-Atomic unit. The obtained results indicate that adsorption energy of H2 on the CT-RGO surface is significantly higher when the electric field is applied along the bond axis, suggesting thereby that hydrogenation of alkene can be induced with CT-RGO catalyst support under external electric fields. The obtained results shed light on the effect of the external electricity field on the graphene-hydrogen complex, the activation energy of graphene radicals to achieve the transition states as well as the adsorption of the hydrogen atoms over the graphene surface. Altogether, the theoretical results presented herein suggested that the proposed catalytic system holds promise for facilitating the alkene hydrogenation under external electric fields.

Nonlinear characteristics of the oil-paper insulation system during the polarization and depolarization process

The oil-immersed transformer plays a pivotal role in the power network. Its insulation stability is essential. At present, the application of time-domain dielectric response technology in insulation detection of oil-immersed equipment is relatively mature. However, there is a contradiction between increasing the test excitation amplitude to improve the test accuracy and the nonlinear response characteristics of the test dielectric at high-voltage excitation. The assessment theories all depend on the laboratory test results, and inaccurate test results will affect the assessment results. Therefore, this paper prepared several groups of insulation-scaled aging models in the laboratory and studied the effects of temperature and test excitation amplitude on the polarization and depolarization characteristics of the models. During the polarization process, the electric intensity variation was calculated. Meanwhile, at the time-varying electric field, the influence mechanism of electric intensity on the response current caused by the charge escaping from the trap during the polarization process was obtained. This paper quantified the relationship between the aging state and the height of the interfacial polarization barrier. The study of nonlinear dielectric response in the time domain will help to improve the accuracy of test results when diagnosing the insulation performance of oil-immersed transformers.

Does China's low-carbon city pilot intervention limit electricity consumption? An analysis of industrial energy efficiency using time-varying DID model

Emissions depletion through pro-environmental interventions by top emitters like China has profound significance in improving the atmosphere's cumulative carbon efficiency. China's electricity sector is accountable for almost 40% of its total aggregated emissions, indicating that China's electricity sector does not yet follow the energy conservation and energy efficiency theories, which require urgent attention if China aspires to achieve carbon emissions peak and neutrality by 2030 and 2050, respectively. Chinese lawmakers have adopted pro-environmental interventions to limit emissions, like constructing low-carbon city pilots (LCCP). LCCP intervention has successfully curbed emissions in China's major cities, which earlier studies have validated. However, no study assesses whether the LCCP intervention supports enterprises in reducing their electric energy consumption intensity (EECI) by upgrading their energy conservation attitude and improving power efficiency. To address this fundamental question, we construct a time-varying difference-in-difference (DID) model to comprehensively investigate the consequences of LCCP intervention on EECI, using matched data from the Chinese Enterprise Pollution Emissions Database and the Chinese Industrial Enterprise Database from 2007 to 2014. The findings unfold as follows: 1) The LCCP intervention significantly reduces the firm's electricity consumption intensity (i.e., a one percentage point increase in LCCP curbs EECI by 3.14%). 2) We observe significant heterogeneity in the effect of LCCP on EECI based on the ownership, location, and input characteristics of the intervened firms (i.e., LCCP has an insignificant effect on EECI for firms that are state-owned, labor-driven, and located in western zones. However, it has a more substantial inhibitory effect on EECI for firms that are: located in non-resource-based cities, foreign and private-owned, capital and technology-driven, and non-western). 3) The LCCP intervention promotes enterprises' power consumption via the energy-saving and green innovation effects, which boosts enterprises' energy conservation attitude and energy efficiency in the long term. The conclusion remains untapped after mitigating sequence-related issues, limiting the influence of alternative policies, employing lagged terms, and deploying different estimation strategies (i.e., PSM-DID). Several policies have been advocated in line with the findings in the ultimate section.

Interaction of Pulsed Electric Modified Elephant Foot Yam (Amorphophallus paeoniifolius) Starch and Polyvinyl Alcohol to Enhance the Mechanical and Barrier Properties of Film

AbstractElephant foot yam starch (EFYS) is modified by the pulsed electric field (PEF, 4–16 kV cm−1) and used for the development of the biodegradable film. The increase in PEF intensity increases the oil (1.66–2.22 g g−1) and water absorption capacity (1.79–2.08 g g−1) and reduces the gelatinization temperature (Tg) and enthalpy (ΔΗ). Storage modulus (G') is found to be higher than loss modulus (G"), indicating strong gel characteristics of EFYS. Electrical intensity affects the degree of crystallinity and disrupts the granule's surface. Film prepared with PEF‐modified EFYS and different concentrations of polyvinyl alcohol (PVA, 25%, 50%, and 90%) shows that the increase in the concentration of PVA results in increased thickness, tensile strength, % elongation, water vapor permeability, water vapor transmission rate, seal strength, and solubility. PEF modification increases the film's mechanical and moisture barrier properties. The study proves that PEF changes the physico‐functional and structural characteristics of EFYS, making it suitable to be used in the biodegradable film.

A Domain-Independent Interaction Integral for Dynamic Fracture in Nonhomogeneous Magneto-Electro-Elastic Materials

In practice, magneto-electro-elastic (MEE) equipment are inevitably subjected to impact loading during service, resulting in fracture failure of the devices. This paper proposes a dynamic domain-independence interaction integral (DII-integral) to solve the dynamic intensity factors (IFs) at the crack tip of MEE materials. Here, this is a new expression of the interaction integral (I-integral) for dynamic crack study of nonhomogeneous MEE media, and we further extend it to MEE materials containing complex interfaces. Domain-independent property of the I-integral is theoretically demonstrated and excellent numerical results (relative deviation<1%) obtained from the various integration domains again verify the domain-independence for nonhomogeneous and multi-interface material properties without considering the material continuity requirements. Through the combination of the DII-integral and extended finite element method (XFEM), a good agreement is observed by comparing with the published data subjected to different MEE impact loadings. Typical examples reveal that the magnitude of dynamic mode-I stress intensity factor (SIF), dynamic electric displacement intensity factor (EDIF) and dynamic magnetic induction intensity factor (MIIF) decrease with the increase of the poling angle of the MEE material, while the dynamic mode-II SIF shows the opposite change. The peaks of dynamic EDIF and MIIF are more sensitive to the distance between the parallel cracks than the SIF, and all IFs are smaller than single crack due to the shielding effect. Finally, the significant difference on the dynamic IFs is observed with various material discontinuities.

Fracture analysis of circular hole edge arbitrary position crack with surface effects in magnetoelectroelastic materials

The mechanical properties of magnetoelectroelastic (MEE) materials are brittle, which is easy to produce nano-defects (hole or crack). The micro-fields of nanoscale cracks and holes are size dependent significantly. Nanoscale cracks and holes interact with each other, and the interference effect is very obvious. In this paper, the Model III fracture behavior of nanoscale circular hole edge arbitrary position radial crack is studied under anti-plane mechanical load, in-plane electric displacement load and in-plane magnetic induction load. Based on the surface elasticity theory, the conformal mapping technique and the MEE elasticity theory, the MEE fields expressions of the nano-hole and nano-crack are obtained, and the analytical solution of generalized intensity factors (stress intensity factor, electric displacement intensity factor and magnetic induction intensity factor) at crack tip is given. The comparison between the present results and the existing research shows the correctness of the present method in this paper. The influences of the microstructure and coupling loads on the generalized intensity factors are discussed.

The anti-cariogenic effect of fluoride iontophoresis on sound enamel under different working conditions: an in vitro study

Objective. This study investigated the anti-cariogenic effect of fluoride iontophoresis on sound human enamel under different working conditions. Methods. One hundred and five enamel blocks were prepared and randomly assigned to seven different groups: Fluoride iontophoresis under different working conditions, including: different electric current intensities (0.2, 0.4, 0.6 mA) and durations of current application (3, 6, 9 min); No fluoride treatment (negative control); Fluoride immersion without iontophoresis (positive control). After 7 days of pH-cycling, morphology changes on enamel surfaces were examined by scanning electron microscopy (SEM), and Vickers surface microhardness (VH) values of enamel blocks before and after treatments were assessed using a Vickers microhardness tester. KOH-soluble fluoride (KOH-F) uptakes were measured by a fluoride ion-selective electrode. Results. Distinctly roughened enamel surfaces were showed in all treatment groups, with the greatest extent damaged surface in negative control group and the least in all the fluoride intophoresis groups. All the fluoride iontophoresis groups (except for the group under 0.2 mA) showed smaller reduction of VH values (p < 0.05) and greater KOH-F (p < 0.05) when compared with the negative and positive control groups. There was an increasing trend in the loss of VH and in fluoride uptakes with an increasing current intensity. Meanwhile, the reduction of VH values and KOH-F in Group I3 ( 0.6 mA) were significantly greater (p < 0.05) than those in Group I1 ( 0.2 mA). No significant differences of reduction of VH and KOH-F presented among the three groups applied with fluoride iontophoresis under different current durations. Conclusions. Fluoride iontophoresis resulted in a significantly increased KOH-F and a reduced loss of VH after the 7 days pH-cycling procedure, and its effectiveness was influenced by different electric current intensities but not influenced by different current durations.

Carbon Reduction Countermeasure from a System Perspective for the Electricity Sector of Yangtze River Delta (China) by an Extended Logarithmic Mean Divisia Index (LMDI)

The electricity sector is a complex system, especially in the Yangtze River Delta (YRD) of China. Thus, the carbon dioxide (CO2) emission of YRD’s electricity sector during 2000–2020 was first calculated and then evaluated from two systematical dimensions of cross-region and the whole process (production, trade, transmission, and consumption) by an extended logarithmic mean Divisia index (LMDI). (1) During 2000–2020, the CO2 emission of YRD’s electricity sector increased from 228.12 Mt to 807.55 Mt, with an average annual growth rate of 6.52%. Compared to other regions, the YRD’s electricity mix effect had the strongest mitigation impact on CO2 growth. Therefore, it is important for YRD to build a low-carbon electricity system itself, including the de-carbonization of electricity production and the carbon reduction of the electricity-use process. (2) Nationally, electricity trade had an overall mitigating impact on emission growth during 2000–2020. This result means that cross-regional cooperation or trade in the electricity sector is beneficial to emission reduction. So, it is important to improve the national power grids to promote trade. (3) Jiangsu had the largest CO2 emissions, while Anhui had the fastest average annual growth rate (9.71%). Moreover, the economic activity effect was the most significant driver in all provinces, especially in Jiangsu and Anhui. Thus, Jiangsu and Anhui should strive to improve the quality of economic growth while vigorously cutting carbon emissions. (4) Electricity transmission loss had an overall driving impact on emission growth in each YRD province, especially in Zhejiang and Anhui. Meanwhile, electricity structure, electricity trade, and electricity intensity were the inhibiting factors. Particularly, the inhibiting effect of Shanghai’s electricity structure was notably weak (−2.17 Mt). So, Shanghai should try hard to increase the proportion of renewable energy, while Zhejiang and Anhui should upgrade their electricity transmission equipment.

The influence of pore characteristics on rock fragmentation mechanism by high-voltage electric pulse

High-voltage electric pulse (HVEP) is an innovative low-energy and high-efficiency technique. However, the underlying physics of the electrical breakdown within the rock, and the coupling mechanism between the various physical fields involved in HVEP still need to be further understood. In this study, we establish a 2D numerical model of multi-physical field coupling of the electrical breakdown of porous rock with randomly distributed pores to investigate the effect of pore characteristics (porosity, pore media composition) on the partial electrical breakdown of rock (i.e. the generation of a plasma channel inside the rock). Our findings indicate that the generation of a plasma channel is directionally selective and extends in the direction of a weak electrical breakdown intensity. As the porosity of the rock increases, so does the intensity of the electric field in the ‘electrical damage’ region—the greater the porosity, the greater the effectiveness of rock-breaking. As the fraction of pore fluid (S water/S air) gradually declines, the generation time of the plasma channel decreases, and the efficacy of rock-breaking by HVEP increases. In addition, in this study, we conducted an indoor experiment utilizing an electric pulse drill to break down the rock in order to recreate the growth mode of the plasma channel in the rock. Moreover, the experimental results are consistent with the simulation results. In addition, the development of this type of partial electrical breakdown is confirmed to be related to electrode polarity and pore characteristics via the experiment of the symmetrical needle-needle electrode arrangement, which further demonstrates the mechanism of partial electrical breakdown. This research is significant for comprehending the process of electric impulse rock-breaking and gives theoretical guidance and technological support for advancing electric impulse drilling technology.

Effect of composition of geopolymer composites containing fly ash and waste glass powder on their durability and resistivity demonstrated in presence of a nanocarbon additive in a form of graphene

The objective of this study was to obtain a geopolymer composite with semi-conductive or conductive properties for self-control of abnormal symptoms caused by damages to its microstructure. For that purpose effects of different content of fly ash, waste glass powder, as well as two types of graphene and hydrophilic and hydrophobic nanosilica on electrical, physical and mechanical properties were tested. Measurements of resistivity showed the capacity for electrical charge flow in composites, which depended on their composition and products of the geopolymer hardening process. Based on results of the electrical charge flow intensity and observations of geopolymer composite microstructure by means of XRD and scanning microscopy, a possible course of the electrical conductivity mechanism in geopolymer materials was indicated. It was found that geopolymer composites containing fly ash, as well as addition of graphene and hydrophobic nanosilica, showed the most favourable electrical charge conductivity parameters and the highest strength gain.

Future hotter summer greatly increases residential electricity consumption in Beijing: A study based on different house layouts and shared socioeconomic pathways

Emerging studies illustrated that climate change has great impacts on residential electricity consumption, but only a few studies focused on impacts of daily weather and extreme hot days, not to mention considering house layouts. Here, we establish U-shaped response functions between daily outdoor air average temperature and residential electricity intensity (electricity consumption per unit house construction area), based on four house layouts; then we examine how climate change challenges residential electricity consumption in Beijing during the non-heating period under four shared socioeconomic pathways. Small houses are characterized with higher residential electricity intensity, while large houses present stronger marginal effects at high temperature. With present population, housing vacancy rate and house traits, climate change will increase 5%∼7% of residential electricity consumption in near future (2021–2050) and up to 29% in far future (2051–2100) during the non-heating period. Three hot summer months (June, July and August) contribute to more than 1/2 of total consumption and 76∼84% of the increase in future due to more hot days (≥ 20 °C). Residential electricity consumption in Beijing was much lower under the low-warming scenario of SSP1–2.6 than other scenarios, as well as the grid system pressure at peak consumption. Our findings also highlighted the awareness of huge challenges to vulnerable groups, considering climate change, higher electricity price and aging society in future.

Effect of local administration of eicosapentaenoic acid on the jaw-opening reflex in rats.

Although eicosapentaenoic acid (EPA) application in vitro inhibits voltage-gated Na+ (Nav) channels in excitable tissues, the acute local effect of EPA on the jaw-opening reflex in vivo remains unknown. The aim of the present study was to determine whether local administration of EPA to adult male Wistar rats could attenuate the excitability of the jaw-opening reflex in vivo, including nociception. The jaw-opening reflex evoked by electrical stimulation of the tongue was recorded by a digastric muscle electromyogram (dEMG) in pentobarbital-anesthetized rats. The amplitude of the dEMG response was significantly increased in proportion to the electrical stimulation intensity (1×-5× threshold). At 3×, local administration of EPA dose-dependently inhibited the dEMG response, lasting 60min, with maximum inhibition observed within approximately 10min. The mean magnitude of dEMG signal inhibition by EPA was almost equal to that observed with a local anesthetic, 1% lidocaine, and with a half dose of lidocaine plus a half dose of EPA. These findings suggest that EPA attenuates the jaw-opening reflex, possibly by blocking Nav channels of primary nerve terminals, and strongly support the idea that EPA is a potential therapeutic agent and complementary alternative medicine for the prevention of acute trigeminal nociception.

Estimating the Dominant Life Phase Concerning the Effects of Battery Degradation on CO2 Emissions by Repetitive Cycle Applications: Case Study of an Industrial Battery System Installed in an Electric Bus

Many studies have evaluated CO2 emission from batteries. However, the impact of Li-ion battery (LiB) degradation on the CO2 emissions from the material through operation phases has not been sufficiently examined. This study aims to clarify the dominant CO2 emission phase and the impact of the degradation of general industrial LiBs from repetitive cycle applications. We developed a model common to general LiB composition and calculated CO2 emissions by the LCA method using the IDEA database. Our model simplifies the degradation process, including capacity decrease and internal resistance increase. We used it in a sensitivity analysis of the carbon intensity of electricity charged to a LiB. The loss mechanism was determined by experimental data for an electric bus with an industrial LiB. The results illustrate that the carbon intensity of electricity affects CO2 emissions dominance, the operation phase for mix (71.3%), and the material phase for renewables (70.9%), and that battery degradation over six years increases the total amount of CO2 emissions by 11.8% for mix and 3.9% for renewables equivalent. Although there are limitations regarding the assumed conditions, the present results will contribute to building a method for monitoring emissions and to standardizing degradation calculations.

Influence of ambient temperature in the city of Portoviejo, Ecuador on the energy performance of photovoltaic modules

&lt;span lang="EN-US"&gt;The research analyzes the influence of the average temperature on the performance of specific photovoltaic solar modules under the environmental conditions of the city of Portoviejo, province of Manabí, Ecuador. The research is carried out using the qualitative methodology. Its main objective is to determine the influence of temperature on the energy performance of photovoltaic modules under the region's environmental conditions. Two electrical diagrams with different configurations were designed, which were analyzed and simulated using the MATLAB Simulink software. The results obtained show the direct relationship between the electrical parameters of voltage, current intensity, and power with the temperature value on the surface of the modules. It is concluded that the modules generate a higher value of voltage, electric current intensity, and electric power at a lower temperature, regardless of the level of solar irradiation they receive.&lt;/span&gt;