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All‐solid‐state batteries (ASSBs) are emerging as promising candidates for next‐generation energy storage systems. However, their practical implementation faces significant challenges, particularly their requirement for an impractically high stack pressure. This issue is especially critical in high‐energy density systems with limited negative‐to‐positive electrode capacity ratios (N/P ratios), where uneven lithium (Li) stripping induces the formation of interfacial voids. This study addresses these challenges by introducing an anode with a novel structural design that operates effectively under practically viable conditions while significantly reducing the N/P ratio to less than one. The approach entails the integration of a lithiophilic magnesium (Mg) film beneath a thin layer of the silicon‐graphite (SiGr) active materials. This structure facilitates the deposition of excess Li beneath the SiGr layer during overcharging, which enables stable cycling even at room temperature and at a low stack pressure of 3 MPa. By mitigating the poor contact that is characteristic of ASSBs with a low stack pressure, and simultaneously increasing the energy density by lowering the N/P ratio, the design significantly advances the key electrochemical properties of ASSBs. [ABSTRACT FROM AUTHOR]

Lithium‐ion capacitors (LICs), as the next generation of supercapacitors, combine the high power density and long cycle life of supercapacitors with the high energy density of lithium‐ion batteries, presenting broad prospects for applications and becoming a focal point of research in academia and industry. Safety concerns regarding LICs, particularly the crucial issue of thermal safety, have garnered widespread attention. This study investigates the thermal abuse, electrical abuse, and mechanical abuse of 1100 F LICs, including overheating, overcharging, overdischarging, needling, extrusion, and short circuit tests, with real‐time monitoring of temperature, gas emissions, and voltage to explore thermal runaway mechanisms. The results demonstrate that LICs remain safe under abusive conditions, with no occurrences of fire or explosion hazards. [ABSTRACT FROM AUTHOR]

In this study, a flower-like Au/CeO2 supported catalyst composite anode was prepared to explore its impact on thermal runaway triggered by overcharging and flame. Through structural and performance characterization, it was found that the catalyst has a high specific surface area and good CO catalytic oxidation capability, with a CO removal rate higher than 99.97% at room temperature. Through electrical performance testing, it was discovered that, compared to batteries without the catalyst, batteries using the composite anode did not exhibit significant capacity degradation. In overcharge testing, the catalyst prolonged the voltage rise time and peak voltage occurrence time of the battery. In thermal runaway testing, the addition of the catalyst delayed the detection time of CO and significantly reduced the concentration of thermal runaway products, especially the peak concentration and integrated concentration of CO, demonstrating its effectiveness in reducing thermal runaway products. Therefore, this study provides a new approach for improving the safety of lithium-ion batteries. The catalyst exhibits good performance in reducing toxic gases generated after thermal runaway and delaying the occurrence of thermal runaway, providing strong support for the safe application of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

O artigo busca discutir desafios metodológicos relacionados ao estudo comparado da overcharging norte-americana. Sem discrepar do que ocorre em relação à análise comparada do sistema jurídico estadunidense, o estudo comparado da overcharging possui limitações e demanda cuidados específicos. No entanto, o emprego de métodos que diminuam o risco de equívocos e que permitam uma melhor compreensão dos institutos jurídicos norte-americanos pode contribuir decisivamente para o alcance das finalidades do estudo comparativo.

An open-end winding arrangement is fed with two typical 2-level voltage source inverters (VSIs) on either side to accomplish multilevel inversion. Two voltage source modules (VSIs) DC-link voltages are kept at a 2:1 ratio to realize the open-end winding induction motor (OEW-IM) power circuit's four-level configuration. However, the higher DC-link voltage capacitor overcharges its lower DC-link voltage counterpart in the 4-level power circuit configuration. This article proposes a new hybrid-clamping space vector PWM (SVPWM) approach to prevent overcharging. Based on the sample moment, the suggested SVPWM technique clamps one inverter and switches to another inverter. Additionally, it clamps one of the inverter's switching phases. The proposed PWM method has been found to reduce switching power loss in contrast to earlier SVPWM methods. The proposed SVPWM scheme for the 4-level OEW-IM drive is tested and verified using an experimental laboratory setup. [ABSTRACT FROM AUTHOR]

This research aims to understand the impact of overcharging on precycled Lithium-Nickel Manganese Cobalt (Li-NMC) batteries through continuous charge and discharge cycles. These Li-NMC cells underwent standard charging and discharging, maintaining their state of health (SOH) above 90% even after 200 cycles. Continuous overcharging of these precycled Li-NMC cells caused their SOH to degrade below 20% within the next 180 cycles. To investigate the underlying reasons for such significant differences in SOH degradation, scanning electron microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) analyses were performed on both pristine and overcharged batteries. The structural changes in the batteries due to overcharging provide valuable insights into the degradation mechanisms. In addition, to predict the health degradation of precycled batteries by utilizing a gradient boost (GB) and support vector machine (SVM) regressor with hyperparameters optimized through Bayesian optimization, tuning of these hyperparameters increases accuracy, where mean squared error (MSE) and root mean squared error (RMSE) decrease more than 65% of the conventional algorithm. The GB and SVM regressors were trained using data acquired during the charge and discharge cycles of the batteries. The trained model demonstrated promising performance in predicting SOH degradation, providing valuable guidance for developing control algorithms for battery management strategies. [ABSTRACT FROM AUTHOR]

Copyright of Legacy: Jurnal Hukum dan Perundang-Undangan is the property of UIN Sayyid Ali Rahmatullah Tulungagung, Department of Constitutional Law and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modeling of electrokinetic flows is crucial to understand numerous phenomena associated with electrochemistry, biophysics, and colloidal science. Here, we incorporate the modified Gaussian renormalized fluctuation theory into transport equations for electrolyte solutions to study the ion‐correlation‐induced inversion of electrokinetic flows, also known as charge inversion. We are able to capture the non‐monotonic dependence of inverted streaming current and reversed electrophoretic mobility on salt concentration. By analyzing the double‐layer structure, we elucidate that this non‐monotonicity is a consequence of the competition between spatially varying ion correlations and the translational entropy of the ions. We find that for practical values of surface charge densities, the excluded volume effect does not play any significant role. In a significant improvement over existing theories, our theoretical predictions are in quantitative agreement with experimental measurements for charge inversion in trivalent salts. [ABSTRACT FROM AUTHOR]

In this study, a flower-like Au/CeO2 supported catalyst composite anode was prepared to explore its impact on thermal runaway triggered by overcharging and flame. Through structural and performance characterization, it was found that the catalyst has a high specific surface area and good CO catalytic oxidation capability, with a CO removal rate higher than 99.97% at room temperature. Through electrical performance testing, it was discovered that, compared to batteries without the catalyst, batteries using the composite anode did not exhibit significant capacity degradation. In overcharge testing, the catalyst prolonged the voltage rise time and peak voltage occurrence time of the battery. In thermal runaway testing, the addition of the catalyst delayed the detection time of CO and significantly reduced the concentration of thermal runaway products, especially the peak concentration and integrated concentration of CO, demonstrating its effectiveness in reducing thermal runaway products. Therefore, this study provides a new approach for improving the safety of lithium-ion batteries. The catalyst exhibits good performance in reducing toxic gases generated after thermal runaway and delaying the occurrence of thermal runaway, providing strong support for the safe application of lithium-ion batteries.

O presente trabalho visa a avaliar se existe um risco relevante de ocorrência do overcharging nas práticas negociais do Direito Penal brasileiro, tomando como base a definição desse conceito no Direito norte-americano e as condições que favorecem sua existência nos Estados Unidos. Ao final, verifica-se em que medida essas condições se reproduzem no Direito brasileiro, especificamente em relação aos institutos da transação penal e do acordo de não persecução penal.

This section explores the decision of the New South Wales Professional Standards Committee, in Re Teo [2023] NSWMPSC 2. The case provides insights into how the Health Practitioner Regulation National Law Act 2009 (Qld) regulates practitioners who practise outside of conventional practice. The section compares the decision to similar cases and then concludes with a proposal that an express policy on unconventional practice is needed in Australia. [ABSTRACT FROM AUTHOR]

Polyanionic material, specifically the NASICON‐type material, is considered a promising cathode material for Na‐ion batteries (SIBs) because of its stable structure and high operating voltage. Further, it improves the energy density correlated with the well utilization of all Na in the compound. For Na3V2(PO4)2F3 (NVPF), the extraction of the third Na, reported as the electrochemical inactivated, can be realized at a high voltage region while forming an irreversible tetragonal phase. In this study, we introduce Ti doping to the Na2VTi(PO4)2F3 (NVTPF) material; we reveal that the Ti‐doped NVTPF could effectively suppress the irreversible phase transformation, thus successfully harnessing Na in a wide voltage range. Experimental study discloses that the Ti‐substituted Na2VTi(PO4)2F3 could take up the Na+ from Amam phase to Cmc21 phase between 1.0 V and 4.8 V reversibly accounting for the 2 Na+ transportation that shows favorable Na+ kinetics and structural stability. Our research provides the strategy to stabilize the polyanion structure upon charging at a high voltage range and inspires the utilization of full sodium in the polyanionic materials, which could be considered as a material design for future conventional applications. [ABSTRACT FROM AUTHOR]

Overcharging is one of the most serious safety problems in large-scale application of lithium ion battery (LIB). An in-depth understanding of the failure mechanism of battery overcharge is necessary to guide the safe design of battery system. In this paper, the electrochemical performance of commercial 18650-type cylindrical battery with Li(Ni0.5Co0.2Mn0.3)O2 cathode and graphite anode as the background is evaluated with different state of charge (SOC). The dynamic thermal behavior of overcharge in adiabatic conditions is studied, and the cathode materials, separator and anode materials after long-term overcharge cycle are characterized to identify the side reactions in battery. The results show that the battery impedance increases with the increase of SOC, and thereby greatly accelerating the attenuation of battery capacity. When LIB is charged and discharged in adiabatic conditions, the battery surface temperature of 116% SOC is about 10.03 °C higher than that of 100% SOC. Therefore, the battery with higher SOC has higher heating and is easy to induce the thermal runaway reactions. During the overcharge cycle, electrolyte decomposition, transition metal dissolution and phase transformation occur at the cathode, and serious lithium plating occur at the anode, as a result, increasing battery impedance, accelerating aging and increasing heat production. These results provide feasible support for understanding the overcharge mechanism and battery management system.

Charged biopolymers able to adsorb solubilized metal cations instead of precipitating them as inorganic waste provide a sustainable option for conventional lime treatment of acidic metal-bearing effluents. We investigated the adsorption of trivalent iron (Fe3+) and lanthanum (La3+) on anionic TEMPO (2,2,6,6-tetramethyl-piperidine-1-oxyl)-oxidized nanofibrillated cellulose (TONFC) from concentrated solutions at increasing ionic strengths (I). In the adsorption experiments, solutions containing 25–150 mM FeCl3 or LaCl3 as such (I0), or with I adjusted to 1 (I1) or 4 (I4) with NaCl, were treated with TONFC. Following filtration, the solutions were subjected to pH measurement and analysis for the TONFC-induced changes in Fe and La concentrations. The susceptibility of the retained metals to desorption was elucidated by back extraction. Adsorption of Fe3+ and La3+ significantly exceeded the negative charge density of TONFC, which led to positive overcharging of cellulose fibrils. The consequent Coulomb repulsion between the fibrils prevented their aggregation and enabled metal retention even under highly acidic conditions. At high I, Na + ions derived from the NaCl background were unable to compete with Fe3+ or La3+ for the sorption sites. Excess of Cl- ions, in turn, produced chloride complexes, particularly with Fe3+. They abated overcharging, which induced TONFC condensation and reduced Fe sorption within a critical concentration range. Above this range, Fe sorption recovered presumably due to partial redispersion of cellulose fibrils. Analogous condensation and redispersion of TONFC was not detected in the reaction with La3+. In conclusion, its overcharging tendency renders TONFC a superior agent for the treatment of highly concentrated metal-bearing effluents of very low pH. Successful utilization of the material as a water purification agent, however, requires understanding of the re-entrant behavior of TONFC with solutions of high I.

Lithium ion batteries (LIBs) have become the dominate power sources for various electronic devices. However, thermal runaway (TR) and fire behaviors in LIBs are significant issues during usage, and the fire risks are increasing owing to the widespread application of large-scale LIBs. In order to investigate the TR and its consequences, two kinds of TR tests were conducted triggered by overheating and overcharging ways. The cells are 228 Ah with LiFePO4 as cathode. The TR and fire behaviors were studied comprehensively from the aspect of experimental photographs, temperature characteristics, heat release rate (HRR), total heat release (THR), voltage and mass loss variation. The effects of different triggers were investigated. Under the two trigger conditions, the LIBs did not self-ignite and instead only release a large amount of gases or aerosols. With external ignition sources, the combustion process can be classified into four stages. The relationship between TR and fire behaviors related to the two conditions are discussed, respectively. Compared with overheating, the batteries burn more violently and have higher fire risks during overcharging tests. The work is supposed to provide valuable fundamental data and theory guidance for early warning technology and fire protection. [ABSTRACT FROM AUTHOR]

Battery overcharging can occur due to capacity and internal resistance variations among cells or battery management system failure that both accelerate battery degradation, which is more likely at low temperatures because of the large polarization effect. This study experimentally investigated the battery degradation characteristics during charging of LiFePO4 (LFP)/Graphite batteries at voltages of 3.65–4.8 V and Li(Ni0.5Co0.2Mn0.3)O2 (NCM)/Graphite batteries at 4.2–4.8 V at −10 °C with currents of 0.2–1 C. The results showed that the LFP cell capacities decreased linearly with an increasing number of cycles, while the NCM cell capacities faded in three trends with an increasing number of cycles under different conditions with linear fading, accelerated fading, and decelerated fading. The incremental capacity curves and differential voltage curves showed that the LFP cell degradation was mainly caused by the loss of lithium inventory (LLI), with some effect from the loss of active material (LAM). In the NCM cells, both the LLI and LAM significantly contributed to the degradation. Combined with internal battery morphology observations, the LAM mainly occurred at the anode, and the main side reactions leading to the LLI with lithium plating and solid electrolyte interface growth also occurred at the anode. [ABSTRACT FROM AUTHOR]

Asymmetric behaviors of capacitance and charging dynamics in the cathode and anode are general for nanoporous supercapacitors. Understanding this behavior is essential for the optimal design of supercapacitors. Herein, we perform constant-potential molecular dynamics simulations to reveal asymmetric features of porous supercapacitors and their effects on capacitance and charging dynamics. Our simulations show that, counterintuitively, charging dynamics can be fast in pores providing slow ion diffusion and vice versa. Unlike electrodes with single-size pores, multi-pore electrodes show overcharging and accelerated co-ion desorption, which can be attributed to the subtle interplay between the dynamics and charging mechanisms. We find that capacitance and charging dynamics correlate with how the ions respond to an applied cell voltage in the cathode and anode. We demonstrate that symmetrizing this response can help boost power density, which may find practical applications in supercapacitor optimization.

Battery safety tests are defined by several international standards in different ways and with heterogenous termination and failure criteria. In this work, lithium-ion cells were examined regarding their behavior in the event of overcharging and also in the event of an external short circuit with varied parameters specified by standards. The voltage, current, and temperature curves were evaluated. In addition, the changes in the cells were analyzed using electrochemical impedance spectroscopy (EIS). It is shown that the cells exhibit reproducible behavior in a clamped state. Further, it could be determined that the position of the cell opening during an overcharge has an influence on the further behavior of the cell. EIS data showed that the cells have a significantly higher internal resistance after an overcharge. The short-circuit tests at different ambient temperatures indicated that the internal resistance of the cell decreases with increasing temperature. However, no reproducible effects in impedance spectra were present after the short-circuit test. This work illustrates that the choice of test parameters and termination criteria undoubtedly influence the test results and thus may change the classification of cells as either safe or unsafe. Thus, cells may be classified as safe regarding a certain standard but unsafe regarding another. [ABSTRACT FROM AUTHOR]

As negatively charged polyelectrolytes, alginate conformation is greatly influenced by ionic environment, which is of critical importance for solution properties and practical applications. To advance our understanding of alginate conformation in the presence of non-specific ions (NaCl, KCl, MgCl 2), high resolution atomic force microscopy, together with statistical analysis, is employed to provide direct structural information. Alginate chains undergo a collapse-reexpansion transition with increasing salt concentration, which is quantitatively evidenced by a nonmonotonic evolution of persistence length (L p). At low salt concentrations, a decrease in L p is caused dominantly by electrostatic screening effect as electrostatic persistence length (L p e ) shows a strong dependence on Debye screening length (κ −1) with a scaling relation of L p e ∼ κ −2, which is in agreement with Odijk-Skolnick-Fixman theory described for semiflexible polyelectrolytes. Above a certain salt concentration, there is a rise in L p , which can be explained by overcharging and ion-ion correlations. The type of salt also affects the change degree of persistence length, with divalent ions (Mg2+) showing the greatest collapse and reexpansion level. Since alginate chains containing higher α-L-guluronate (G) content are more influenced by salts, it can be inferred that non-specific ions have a higher affinity for G units. [Display omitted] • Upon addition of non-specific ions, alginate undergoes a collapse-reexpansion transition. • Corresponding to the conformational transition, the persistence length shows a nonmonotonic evolution. • The chain collapse is caused dominantly by electrostatic screening effect. • Overcharging and ion-ion correlations could account for chain reexpansion. • Non-specific ion types and alginate composition affect the chain conformation. [ABSTRACT FROM AUTHOR]

Summary: The comprehensive study of the cascaded latent heat thermal energy storage (LHTES) systems and usage of phase change materials (PCM) are of great interest in the literature. Experimental and numerical measurements have been performed to analyze the performance of LHTES systems employing different PCMs. Overcharging is a known obstacle in the way of deploying a cascaded energy storage system that reduces the stored energy quality and amount. Furthermore, the complicated character of the phase transition of materials conjures up the importance of an accurate model. In the current study, the effects of overcharging a three‐stage cascaded cold LHTES through a concentric dispersion model had been analyzed. Three nanoparticles, Al2O3, CuO, and Fe3O4, in the ethylene glycol and water (EG/W) mixture selected as the heat transfer fluid. Also, three eutectic and hydrated salt solutions were chosen as three PCM materials, encapsulated in spherical high density polyethylene shells, and arranged in three stages, namely, PCM‐1, PCM‐2, and PCM‐3, storing high grade, medium grade, and low grade thermal energy, respectively. To overcome the overcharging issue of the system, two different scenarios were introduced. Results indicate that Al2O3, CuO, and Fe3O4 nanoparticles in the EG/W mixture reach their highest charging efficiency at 74.8%, 69.1%, and 75.1%, respectively. Results also revealed that to reach a shorter overcharging time utilizing Al2O3 and CuO nanoparticles, the optimized ratio of the PCM‐2 to PCM‐1 and PCM‐3 to PCM‐1 capacity were both 0.55. The optimized ratio of the PCM‐2 to PCM‐1 and PCM‐3 to PCM‐1 capacity utilizing Fe3O4 nanoparticles were 0.68 and 0.61, respectively. To maintain the highest charging thermal efficiency, the optimized ratio of the PCM‐2 to PCM‐1 and PCM‐3 to PCM‐1 heat capacity was 0.55 for all the three nanofluids. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of monitoring institutions on market outcomes in health care. Healthcare markets are characterized by asymmetric information. Physicians have an information advantage over patients with respect to appropriate treatments, which they may exploit through over- or under-provision or by overcharging. We introduce two types of costly monitoring: endogenous and exogenous monitoring. When monitoring detects misbehavior, physicians have to pay a fine. Endogenous monitoring can be requested by patients, while exogenous monitoring is performed randomly by a third party. We present a toy model that enables us to derive hypotheses and test them in a laboratory experiment. Our results show that introducing endogenous monitoring reduces the level of undertreatment and overcharging. Even under high monitoring costs, the threat of patient monitoring is sufficient to discipline physicians. Exogenous monitoring also reduces undertreatment and overcharging when performed sufficiently frequently. Market efficiency increases when endogenous monitoring is introduced and when exogenous monitoring is implemented with sufficient frequency. Our results suggest that monitoring may be a feasible instrument to improve outcomes in healthcare markets. [ABSTRACT FROM AUTHOR]

In a credence goods market, a consumer (he) is unaware of his true need, which can be either intense or minor. An expert (she) designs a menu that either charges a uniform price to both services, termed pooling pricing, or varies charges according to service types, termed differential pricing. Learning the menu offered by the expert and anticipating her behavior in serving consumers, a consumer weighs the expected utility of service provision against the cost incurred in transportation to decide whether to visit the expert, termed entry decision. Upon arrival of a consumer, the expert discerns his true need and recommends a service along with the associated charge. Under the liability assumption, the expert provides a service to satisfy the consumer's need. However, the consumer is unable to discern the nature of the service actually provided. This can induce the expert who adopts differential pricing to recommend intense service to a consumer with minor need, termed overcharging. We investigate the effects of consumers' entry decision on the expert's optimal pricing strategy and the occurrence of overcharging, and study the robustness of the main results to practical features. [ABSTRACT FROM AUTHOR]

The stability of colloidal dispersions in the presence of multivalent ions depends strongly on the electrostatic interactions between the suspended particles. Of particular interest are colloidal particles having dimensions in the nanometric range and with an anisotropic shape due to its high surface area per unit mass, for example clay, which has the key characteristic of a negatively charged surface, surrounded by an oppositely charged rim. In this study, we investigate the interactions in nanoplatelet dispersions for the model system of Laponite® clay with addition of mono- and multivalent salt. Molecular dynamics simulations with enhanced umbrella sampling have been utilised in combination with the experimental techniques of zeta-potential measurements, dynamic light scattering, and transmission electron microscopy. It was observed that tactoid formation and tactoidal dissolution due to overcharging occur upon the addition of trivalent salt. The overcharging effect was captured from calculated potential of mean force and confirmed from the zeta-potential, which changed sign from negative to positive when increasing the stoichiometric charge-ratio between the positive salt ions and the clay. Consequently, the gained information could provide useful physical insight of nanoplatelet interactions in the presence of multivalent ions. [ABSTRACT FROM AUTHOR]

The popularity and development of alternative energy vehicles have drawn critical attention to thermal safety concerns. The occurrence of fire and explosion due to thermal runaway propagation (TRP) has become a hurdle in developing new energy vehicles. Therefore, to study the TRP behavior of modules subjected to overcharged electrical abuse, we built a 1 × 5 pouch Li-ion battery module TRP model that combines a P2D electrochemical model and a 3D thermal runaway model. We present a complete analysis of TRP characteristics by examining TRP behavior under various design parameters such as thermal runaway trigger temperature (T TR), cell spacing (L), thermal conductivity (K), and heat dissipation coefficient (h). Increasing T TR can delay TR in each cell, effectively slowing the propagation speed, and TRP is prevented at T TR = 583 K. As L increases, the TRP is considerably extended, but TR in the overcharged cell is shortened. The higher K has a delaying impact on the TR of the overcharged cell but leads to a noticeably shorter TRP time. Higher h slows TRP and prolongs TR trigger time of the overcharged cell. We also investigated the intrinsic mechanism of TRP suppression by performing a heat flux analysis and screening several critical cases for TRP suppression. TRP's actual condition is delineated along a criticality line, distinguishing between propagation and non-propagation phases, and confirmed by experimental validation of typical TRP, critical TRP, and non-TRP cases. Furthermore, we studied the parameters requirement for battery module thermal management in the non-TRP region. These findings provide valuable insights for enhancing the safety design of battery systems and mitigating heat-related hazards. [Display omitted] • Develop a TRP model with P2D electrochemical and 3D thermal models. • Detailed analysis of thermal runaway propagation characteristics and behavior. • Screen several critical cases of TRP suppression. • Criticality boundary divides the TRP situation into safe and dangerous regions. • Obtain the non-TRP battery module design parameters requirements. [ABSTRACT FROM AUTHOR]

The role of hydrolyzable metal ions in the adsorption of anionic surfactants on a negatively charge surface is studied by electrophoresis and phase transfer experiments. The notion that the presence of such hydrolyzable species (activators) can promote flotation is not new, but a detailed mechanistic explanation is lacking. We relate the role of activators to the phenomenon of overcharging, which has been studied rather extensively within colloid and interface science. The experiments conducted in this article show that overcharging is a necessary condition for the adsorption of an anionic surfactant on a negatively charged surface and that the hydrophobization of the studied particles is most effective when overcharging is most pronounced.

The spontaneous encapsulation of genomic and non-genomic polyanions by coat proteins of simple icosahedral viruses is driven, in the first instance, by electrostatic interactions with polycationic RNA binding domains on these proteins. The efficiency with which the polyanions can be encapsulated in vitro, and presumably also in vivo, must in addition be governed by the loss of translational and mixing entropy associated with co-assembly, at least if this co-assembly constitutes a reversible process. These forms of entropy counteract the impact of attractive interactions between the constituents and hence they counteract complexation. By invoking mass action-type arguments and a simple model describing electrostatic interactions, we show how these forms of entropy might settle the competition between negatively charged polymers of different molecular weights for co-assembly with the coat proteins. In direct competition, mass action turns out to strongly work against the encapsulation of RNAs that are significantly shorter, which is typically the case for non-viral (host) RNAs. We also find that coat proteins favor forming virus particles over nonspecific binding to other proteins in the cytosol even if these are present in vast excess. Our results rationalize a number of recent in vitro co-assembly experiments showing that short polyanions are less effective at attracting virus coat proteins to form virus-like particles than long ones do, even if both are present at equal weight concentrations in the assembly mixture. [ABSTRACT FROM AUTHOR]

Using the hypernetted-chain/mean spherical approximation (HNC/MSA) integral equations we study the electrical double layer inside and outside a model charged cylindrical vesicle (nanopore) immersed into a primitive model macroions solution, so that the macroions are only present outside the nanopore, i.e., the vesicle wall is impermeable only to the external macroions. We calculate the ionic and local linear charge density profiles inside and outside the vesicle, and find that the correlation between the inside and outside ionic distributions causes the phenomena of overcharging (also referred to as surface charge amplification) and/or charge reversal. This is the first time overcharging is predicted in an electrical double layer of cylindrical geometry. We also report the new phenomenon of double overcharging. The present results can be of consequence for relevant systems in physical-chemistry, energy storage and biology, e.g., nanofilters, capacitors and cell membranes. [ABSTRACT FROM AUTHOR]

In credence goods markets, experts have better information about the appropriate quality of treatment than their customers. Because experts provide both the diagnosis and the treatment, there is opportunity for fraud. We experimentally investigate how the intensity of price competition and the level of customer information about past expert behavior influence experts' incentives to defraud their customers when experts can build up reputation. We show that the level of fraud is significantly higher under price competition than when prices are fixed, as the price decline under a competitive-price regime inhibits quality competition. More customer information does not necessarily reduce the level of fraud. [ABSTRACT FROM AUTHOR]

• A new solution to overcharging problem of cascaded latent heat storage system. • Overcharging time and overcharging time ratio reduce by up to 89.66% and 91.93% • Mean total heat storage rate increases by 67.69% during the melting process. • Tuned porosity arrangement prolongs discharging time and increases discharged heat. • Optimal tuned porosity arrangement is 0.90–0.95–0.97 for a three stage system. Cascaded latent heat storage (CLHS) has been used for building heating to balance renewable energy supply–demand mismatch and improve thermodynamic performance. In a cascaded latent heat storage system, the asynchronous phase transformation process of phase change materials (PCMs) at each stage leads to an overcharging problem, which reduces the heat storage rate and increases the heat loss. This study proposes a new solution to overcome this problem by embedding porous media with tuned porosity arrangement in cascaded PCMs. A 3-D transient numerical model is established to investigate the effects of tuned porosity arrangement on the charging and discharging performance of a CLHS system. The results show that this solution improves the synchronization of the phase transformation process of the PCMs to increase the latent heat storage rate and eventually the total heat storage rate of the system. Compared with a uniform porosity arrangement, the overcharging time and the overcharging time ratio of the system with tuned porosity arrangement decrease up to 89.66% and 91.93%, while the mean total heat storage rate increases by 73.21% during the melting process. In addition, the tuned porosity arrangement is beneficial to prolong heat supply time and increase the accumulated discharged heat. In all cases, the optimal tuned porosity arrangement is 0.90–0.95–0.97. The CLHS system with tuned porosity arrangement has the general good performance under different charging and discharging conditions. The proposed solution provides guidance for performance enhancement and optimization of CLHS systems for building heating. [ABSTRACT FROM AUTHOR]

• The overcharging behaviors of lithium-ion batteries are investigated. • The influence of overcharge depth and number of cycles are examined. • The EIS and IC-DV analysis are used to diagnose cells degradation. • Degradation modes during overcharging are identified and quantified. • Non-destructive fault diagnosis method is put forward. This paper explores the major degradation characteristics of commercial lithium-ion battery cells with nickel–cobalt-aluminum-oxide (NCA) electrode during cyclic overcharging, and proposes non-destructive methods for detecting overcharging degradation failure. The experimental results show that battery capacity drops significantly with increasing overcharge depth and number of cycles especially during the first three cycles and when the charging termination voltage is set to 5 V. At the same time, the cell overcharge tolerance decreases with the cyclic overcharging. The combination of the electrochemical impedance spectroscopy and the incremental capacity and differential voltage analysis is used to diagnose cell degradation during cyclic overcharging. Three main degradation modes are identified and quantified by extracting characteristic parameters such as internal resistance and peak, valley, and curve position changes of incremental capacity curves. It is concluded that loss of lithium inventory and loss of active materials are the most dominant degradation modes during cyclic overcharging. Besides, the sharp increase of the third peak on incremental capacity curves has been identified as a unique feature of overcharging degradation, which can be used for diagnosing cyclic overcharging-induced degradation for batteries with NCA cathode. [ABSTRACT FROM AUTHOR]

The structure and dynamics of negatively charged nucleic acids strongly correlate with the concentration and charge of the oppositely charged counterions. It is well known that the structural collapse of DNA is favoured in the presence of additional salt, a source of excess oppositely charged ions. Under such conditions single stranded DNA adopts a collapsed coil like conformation, typically characterized by stacking base pairs. Using atomistic molecular dynamics simulation, we demonstrate that in the presence of additional divalent salt (MgCl 2 ) single stranded DNA with base sequence 5′-CGCGAATTCGCG-3′ (Dickerson Drew dodecamer) initially collapses and then expands with increasing salt concentration. This is due to the overcharging induced DNA chain swelling, a dominant factor at a higher divalent salt concentration. In a nutshell, our simulations show how in the presence of divalent salt, non-sequential base stacking and overcharging competes and affect single stranded DNA dynamics unlike a monovalent salt. [ABSTRACT FROM AUTHOR]

Useful lessons can be learned from a 2013 Singapore case on overcharging in the medical profession. This article examines the ethical obligations for medical practitioners related to overcharging, the reasons given, and the implementation issues of these obligations. The case provides useful rules and guidelines for medical practitioners and other professionals, such as lawyers and engineers, especially those in common law jurisdictions, where no such rules exist. [ABSTRACT FROM AUTHOR]

Abstract: The adsorption of different organic acids and their influence on the pH-dependent charging, salt tolerance and so the colloidal stability of magnetite nanoparticles are compared. Adsorption isotherms of citric acid – CA, gallic acid – GA, poly(acrylic acid) – PAA, poly(acrylic-co-maleic acid) – PAM and humic acid – HA were measured. The pH-dependent charge state of MNPs was characterized by electrophoretic mobility and their aggregation by dynamic light scattering. The salt tolerance was tested in coagulation kinetic experiments. Although the adsorption capacities, the type of bonding (either H-bonds or metal ion-carboxylate complexes) and so the bond strengths are significantly different, the following general trends have been found. Small amount of organic acids at pH<∼8 (the pH of PZC of magnetite) – relevant condition in natural waters – only neutralizes the positive charges, and so promotes the aggregation and sedimentation of nanoparticles. Greater amounts of organic acid, above the charge neutralization, cause the sign reversal of particle charge, and at high overcharging promote stabilization and dispersing. The thicker layer of PAA, PAM and HA provides better electrosteric stability than CA and GA. GA undergoes surface polymerization, thereby improving stabilization. The organic acids studied here eliminate completely the pH sensitivity of amphoteric magnetite, but only the polyanionic coverage provides significant increase in resistance against coagulating effects of salts at neutral pH commonly prevailing in natural waters. [Copyright &y& Elsevier]

Nucleic acids are negatively charged macromolecules and their structure properties are strongly coupled to metal ions in solutions. In this article, the salt effects on the flexibility of single-stranded (ss) nucleic acid chain ranging from 12 to 120 nucleotides are investigated systematically by the coarse-grained Monte Carlo simulations where the salt ions are considered explicitly and the ss chain is modeled with the virtual-bond structural model. Our calculations show that, the increase of ion concentration causes the structural collapse of ss chain and multivalent ions are much more efficient in causing such collapse, and both trivalent/small divalent ions can induce more compact state than a random relaxation state. We found that monovalent, divalent, and trivalent ions can all overcharge ss chain, and the dominating source for such overcharging changes from ion-exclusion-volume effect to ion Coulomb correlations. In addition, the predicted Na+ and Mg2+-dependent persistence length lp's of ss nucleic acid are in accordance with the available experimental data, and through systematic calculations, we obtained the empirical formulas for lp as a function of [Na+], [Mg2+] and chain length. © 2012 Wiley Periodicals, Inc. Biopolymers 99: 370-381, 2013. [ABSTRACT FROM AUTHOR]

Abstract: Charging and aggregation of negatively charged carboxyl latex particles in the presence of positively charged linear oligoamines containing 1–6 amine groups were investigated by electrophoretic mobility and dynamic light scattering. The oligoamines of low valence resemble simple inert salts and destabilize the suspensions by screening their charge. The oligoamines of higher valence induce overcharging at low concentrations, whereby destabilization is triggered by charge neutralization. At higher concentrations, destabilization is also induced by screening. The onset of first fast aggregation regime scales with the inverse six power of the valence in agreement with the Schulze–Hardy rule. The aggregation rates can be relatively well described by the DLVO theory which indicates that the interactions are governed by van der Waals and electrostatic double layer forces. [Copyright &y& Elsevier]

We study the effective interactions between a test charge Q and a one-component plasma, i.e. a complex made up of mobile point particles with charge q, and a uniform oppositely charged background. The background has the form of a flat disk, in which the mobile charges can move. The test particle is approached perpendicularly to the disk, along its axis of symmetry. All particles interact by a logarithmic potential. The long and short distance features of the effective potential-the free energy of the system for a given distance between Q and the disk-are worked out analytically in detail. They crucially depend on the sign of Q/ q, and on the global charge borne by the discotic complex, that can vanish. While most results are obtained at the intermediate coupling Γ≡ βq=2 ( β being the inverse temperature), we have also investigated situations with stronger couplings: Γ=4 and 6. We have found that at large distances, the sign of the effective force reflects subtle details of the charge distribution on the disk, whereas at short distances, polarization effects invariably lead to effective attractions. [ABSTRACT FROM AUTHOR]

Abstract: Charging properties and colloidal stability of negatively charged polystyrene latex particles were investigated in the presence of linear poly(ethylene imine) (LPEI) of different molecular masses by electrophoresis and dynamic light scattering (DLS). Electrophoretic mobility measurements illustrate that LPEI strongly adsorbs on these particles leading to charge neutralization at isoelectric point (IEP) and charge reversal. Time-resolved DLS experiments indicate that the aggregation of the latex particles is rapid near the IEP and slows down away from this point. Surprisingly, the colloidal stability does not depend on the molecular mass, which indicates that the adsorbed LPEI layer is rather homogeneous. [Copyright &y& Elsevier]

Abstract: Surface charges and electrokinetic charges are very different double layer characteristics. It is mandatory to discriminate between them. If for a given system both of them are known, much relevant double layer information becomes accessible. The present state of this juxtapositioning is reviewed on the basis of real physical measurements with well-defined systems. The added information includes counterion adsorption and stagnant layer conduction. Special attention will be paid to overcharging, including an option for distinguishing between interpretation in terms of specific adsorption and ion correlations. [Copyright &y& Elsevier]

Abstract: Further progress has taken place in the theory of surface forces beyond the conventional DLVO theory. The major recent advances are related to more accurate accounting for the ionic nature of liquid interlayer in the calculations of van der Waals forces and for the impact of dispersion interaction of ions with other ions or confining phases on the peculiarities of ion-electrostatic interactions in liquid films. [ABSTRACT FROM AUTHOR]

Abstract: Sulfate-terminated latex particles were investigated in the presence of poly(diallyldimethyl ammonium chloride) (PDADMAC) at pH 4.0 in aqueous KCl electrolyte solutions by dynamic light scattering and electrophoresis, in particular, at high ionic strengths. The polyelectrolyte adsorbs to the latex particles quantitatively until the adsorption plateau is reached. The adsorbed amount at this plateau and the corresponding layer thickness increase with increasing ionic strength. The resulting layers have a thickness of several nanometers. Colloidal stability is qualitatively consistent with electrostatic double layer forces, especially since the system can be fully destabilized at high ionic strengths even at high polyelectrolyte doses. Additional attractive forces due to lateral charge heterogeneities seem to contribute to the destabilization of the system, even for the adsorbed layers in the saturated state. However, this layer does not provide any additional stabilization mechanism due to steric repulsion forces, since the adsorbed polyelectrolyte layers are thin and laterally heterogeneous even in their saturated state. [Copyright &y& Elsevier]

Slight overcharging cycling occurs due to the malfunction of charge control, inconsistency of lithium-ion batteries and inappropriate battery management. It is important to find whether it causes heat accumulate, increases the temperature of battery and triggers thermal runaway. The results of thermal stability test of slightly overcharged batteries indicate that the thermal stability of slightly overcharged battery decreases due to the cathode structure change when the voltage is less than 4.6 V. When it is greater than 4.6 V, lithium plating also makes battery thermal stability decrease. The results of heat generation and thermal runaway tests of batteries with and without current interruption device indicate that the internal resistance increase after slight overcharging is why the heat generation of battery increases. The heat generation induced by side reaction increases when the temperature reaches the threshold. The temperature threshold of exothermic reactions decreases during charging compared to that during rest with the same state of charge (SOC). Although the cycling is interrupted, thermal runaway still occurs. The battery with lower temperature and higher SOC is more dangerous than that with higher temperature and lower SOC in some cases. It is important to control SOC and temperature during charging. • Lithium plating and cathode structure affect thermal stability of the overcharged battery. • Ohmic heat dominates the heat generation during slight overcharging cycling. • Thermal stability of battery decreases during charging compared to rest. • Both high temperature and SOC influence thermal stability of battery. • Abnormal heat generation during CV mode can be used as fault diagnosis parameter. [ABSTRACT FROM AUTHOR]

Abstract: A discussion is given of the experimental evidence for overcharging, also known as charge reversal. The phenomenon is very common. The most general explanation is specific chemical adsorption. However, overcharging can also be explained on the basis of ion-ion correlations, which is rather a physical type of interpretation, and which can also be specific. Several theories have been developed for that. So, there is the luxury problem that two alternative explanations are available for the same observation. The purpose of this paper is to consider the various approaches critically and try to devise experimental options to discriminate between the two interpretations. [Copyright &y& Elsevier]

Previous studies on the surface charge and electrokinetic charge on silver iodide as a function of the pAg in the presence of some monovalent and trivalent cations as the counterions were extended to include the influence of pH. The main reason for this study was to investigate the possible propensity of overcharging by adsorption of hydrolyzed counterions. It was found that for K+ as the counterion the double layer properties could be well represented in terms of a simple Gouy-Stern model, without accounting for hydrolysis. However, with Al3+ or La3+ as the counterions, adsorption of hydrolyzed species takes place when the pH is high enough, leading to electrokinetic charge reversal. [ABSTRACT FROM AUTHOR]