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The presented study focuses on a numerical simulation of the transport phenomena inside a solid oxide fuel cell anode. The classical mathematical model leads to a notable discrepancy between measured and predicted overpotentials. One of the possible reasons is the assumption of the constant values of electrochemical reaction charge transfer coefficients. A modified formulation of the problem includes data-driven correction of reaction charge transfer coefficients in the electrochemical reaction model. Here we show a dedicated computational scheme in which an artificial neural network updates the charge transfer coefficients depending on the operational conditions and the available datasets. The neural network was trained on twelve experimental data points of an anode's polarization curve obtained from the literature. The training set contained data for the anode operating in two different temperatures - 800 °C and 900 °C. The test set contained additional six data points for an anode operating at 1000 °C. Charge transfer coefficients were proposed by the Artificial Neural Network as a functional relation of the temperature and withdrawn current. The results of the predictions are juxtaposed with the experimental data from the literature. It was shown that an Artificial Neural Network could improve an electrochemical reaction model in Solid Oxide Fuel Cell modeling.

Charge transport at the molecular scale builds the cornerstone of molecularelectronics (ME), a novel paradigm aiming at the realization of nanoscaleelectronics via tailored molecular functionalities. Biomolecular electronics,lying at the borderline between physics, chemistry and biology, can be con-sidered as a sub-field of ME. In particular, the potential applications of DNAoligomers either as template or as active device element in ME have stronglydrawn the attention of both experimentalist and theoreticians in the past years.While exploiting the self-assembling and self-recognition properties of DNAbased molecular systems is meanwhile a well-established field, the poten-tial of such biomolecules as active devices is much less clear mainly due tothe poorly understood charge conduction mechanisms. One key componentin any theoretical description of charge migration in biomolecular systems,and hence in DNA oligomers, is the inclusion of conformational fluctuationsand their coupling to the transport process. The treatment of such a problemaffords to consider dynamical effects in a non-perturbative way in contrastto, e.g., conventional bulk materials. Here we present an overview of recentwork aiming at combining molecular dynamic simulations and electronicstructure calculations with charge transport in coarse-grained effective model Hamiltonians. This hybrid methodology provides a common theoretical start-ing point to treat charge transfer/transport in strongly structurally fluctuatingmolecular-scale physical systems.

The research of LEFP (linear explosive forming projectile) is of great value to the development of new warhead due to its excellent performance. To further improve the damage ability of the shaped charge warhead, a special shell overhanging structure was designed to increase the charge based on the traditional spherical charge, in which case the crushing energy of LEFP could be guaranteed. LS-DYNA was used to simulate different charge structures obtained by changing the number of detonation points, the length of shell platform, the radius of curvature and the thickness of liner. The RSM (response surface model) between the molding parameters of LEFP and the structural parameters of charge was established. Based on RSM model, the structure of shaped charge was optimized by using multi-objective genetic algorithm. Meanwhile, the formation process of jet was analyzed by pulsed X-ray photography. The results show that the velocity, length-diameter ratio and specific kinetic energy of the LEFP were closely related to the structural parameters of the shaped charge. After the optimization of charge structure, the forming effect and penetration ability of LEPP had been significantly improved. The experimental data of jet velocity and length were consistent with the numerical results, which verifies the reliability of the numerical results.

This paper obtains fundamental limits on the computational precision of in-memory computing architectures (IMCs). An IMC noise model and associated SNR metrics are defined and their interrelationships analyzed to show that the accuracy of IMCs is fundamentally limited by the compute SNR ($\text{SNR}_{\text{a}}$) of its analog core, and that activation, weight and output precision needs to be assigned appropriately for the final output SNR $\text{SNR}_{\text{T}} \rightarrow \text{SNR}_{\text{a}}$. The minimum precision criterion (MPC) is proposed to minimize the ADC precision. Three in-memory compute models - charge summing (QS), current summing (IS) and charge redistribution (QR) - are shown to underlie most known IMCs. Noise, energy and delay expressions for the compute models are developed and employed to derive expressions for the SNR, ADC precision, energy, and latency of IMCs. The compute SNR expressions are validated via Monte Carlo simulations in a 65 nm CMOS process. For a 512 row SRAM array, it is shown that: 1) IMCs have an upper bound on their maximum achievable $\text{SNR}_{\text{a}}$ due to constraints on energy, area and voltage swing, and this upper bound reduces with technology scaling for QS-based architectures; 2) MPC enables $\text{SNR}_{\text{T}} \rightarrow \text{SNR}_{\text{a}}$ to be realized with minimal ADC precision; 3) QS-based (QR-based) architectures are preferred for low (high) compute SNR scenarios., Comment: 14 pages, 13 figures

U.S. banks countercyclically vary the ratio of charge-offs to defaulted loans (COD) and the standard deviation of COD is roughly 15 times that of GDP. We show that canonical financial accelerator models cannot explain these facts, but introducing stochastic default costs and stochastic risk can potentially resolve the discrepancy. Estimating the augmented model and including both surprise and news shocks reveals that default cost news shocks account for most of the variance of COD. Also, in the many model specifications we work with, default cost news shocks always account for at least 20 percent of the variance of investment, while risk news shocks account for a significant portion of the variation in the credit spread, and around 10 percent of the variation in investment growth. Both news shocks also account for a material amount of the variance of hours and output growth.

In this study, we focused on the effect of the underwater explosion parameters of multi-point array explosion. The shock wave and bubble parameters of aggregate charge, two charges, and four charges were measured through an underwater explosion test, and their influence on the explosion power field of charge quantity and array distance was analyzed. Results show that the multi-shock wave collision of array explosion can be approximated to a linear superposition, and the interaction of delayed shock wave can be deemed as the increase of the shock wave baseline. Shock wave focusing and delayed superposition increase the shock wave peak pressure. Compared with the aggregate charge, the greater the number of array explosion points is, the higher the impulse and the gain of the bubble peak pressure are. At the same array distance, the smaller the charge quantity is, the higher the bubble impulse will be. At the same charge quantity, the smaller the array distance is, the higher the bubble impulse will be. The bubble period decreases gradually with the increase of the charge quantity, but the test orientation has little effect on the bubble period.

Aggregation plays a critical role in modulating the photophysical process of organic molecules. However, the rational control of the construction of a function-oriented stacking mode for efficient ...

The engineering of switchable molecules with dramatic magnetic change is currently among the most active areas in chemical research. Here, two cyanide-bridged mixed-valence {FeIII4FeII4} cubes were...

In this paper, we propose two decentralized Electric Vehicle (EV) charge scheduling schemes for shaping the load curve of residential communities connected to the electric grid. The first scheme is designed for Coordinated Valley-Filling (C-VF) of the load curve via only EV charging. The second scheme is designed for Coordinated Valley-Filling and Peak-Shaving (C-VF-PS) of the load curve via both EV charging and discharging. In both schemes, a set of grid-connected EVs referred to as an `EV Group' (EVG) coordinates their charge (and discharge) schedules by means of an iterative routine. Specifically, at each iteration of the respective routine, each EV in the EVG updates its charge (and discharge) schedule using a water-filling based algorithm that is specifically tailored for load curve shaping. To accommodate heterogeneous EV arrival times, which are often non-deterministic, each of C-VF and C-VF-PS is implemented in two methods, which differ in the way the EVG is formed. The first method requires all the grid-connected EVs to reschedule at designated time intervals, whereas the second method requires each EV to schedule only once, yielding lower computation and communication overheads. Numerical simulation results confirm that, compared to uncoordinated EV charging, C-VF and C-VF-PS reduce the load variance (flattens the load curve) by 47% and 65%, respectively. Furthermore, Method 2 is shown to be more effective than Method 1, in terms of computation and communication overheads.

A molecular spintronics device is considered as a highly promising candidate for the quantum hardware in the field of practical quantum information applications. Within this field, local objects always obey the Coulomb blockade effect, where electrons occupy molecular orbitals monotonically in a step-like manner as the gate voltage sweeps. Herein, based on a single-molecule transistor in an external magnetic field, we predict that the charge occupation of both spin channels may show nonmonotonic filling, characterized by a spin-sensitive charge oscillation, contravening the standard Coulomb blockade behavior. We attribute this nonmonotonicity to the competition among the Zeeman effect, the many-body effect, and the symmetry of the quantum states. To obtain significant oscillations, strong electron–electron interaction and low temperature are prerequisites. We demonstrate that the oscillation goes against the spin-polarized transport, and for appropriate parameters, the transistor may act as a perfect electronically-manipulable bidirectional molecular spintronics device. To implement such an ideal, the state-of-the-art numerical renormalization group method is adopted, and an experimental proposal to test these predictions is suggested.

The nuclear charge pickup cross sections of 40Ar on polyethylene(CH2), carbon, aluminum, copper and lead targets at the highest energy of 495 MeV/n were measured using CR-39 nuclear track detector. The cross sections for H were calculated from those measured on C and CH2 targets. The dependence of charge pickup cross section on target mass was studied, it was found that the nuclear charge pickup cross section exhibits a linear dependence on the target mass.

In this paper, effects of pectin varying in overall charge (OCH) and local charge density (LCD) on the structure and thermal stability of Lysozyme (lys) are studied. The secondary and local tertiary structures of lys undergo at pH 5.1 a two-step change upon binding with increasing amounts of pectin, in which the peak of fluorescence first increases and shows a blue shift and the amount of helix conformation drops at a pectin/lys mass ratio (q) below or equal to that corresponding to maximal complexation qmax. With increasing amount of pectin, the native like state is recovered at q > qmax. The decrease in helix content depends mainly on the OCH of pectin. Analysis of the thermodenaturation behavior of lys reveals that affinity of pectin with denatured lys is higher than for the native state of lys. At the same OCH of pectin, unfolding of lys is more significant in case of a high LCD (blockwise distribution of charges) of the former. At q = qmax (first stage of binding) the key factors stabilizing lys within its complexes with pectin against thermo-aggregation are a high LCH of pectin and, to a lesser degree, a low OCH. At q > > qmax (second stage of binding), a high LCH of pectin is a key factor inhibiting thermo-aggregation of lys.

This paper proposes a time-domain method of characteristics to simulate the impulse corona with background space charge, and derives the ordinary differential equations of the space charge generated by the impulse corona along the electric field line. The corresponding boundary conditions, the selection of time step and space step, and the update strategy of space charge are given. The calculation result of the impulse corona onset voltage is consistent with the test result, proving that the background space charge has almost no effect on the impulse corona onset electric field which is obtained by Kaptzov's assumption. The q-u curve obtained by simulation is compared with the test results to verify the effectiveness of the simulation method. The simulation method is used to obtain the development process of space charge during the application of the opposite polarity impulse voltage. By analyzing the space charge distribution during the process of impulse corona, and the corresponding microscopic charge distribution and macroscopic charge amount at different corona states, the characteristics of impulse corona are explained.

The random mobility of charge carriers is a main factor causing the low photocatalytic efficiency of g-C3N4. Thus, the controllable migration of charge carriers is a rational strategy to suppress the charge recombination and facilitate charge separation. Herein, an ethylenediamine modified g-C3N4 displays improved photocatalytic activity. The excellent charge separation efficiency is confirmed to be a key factor for the enhancement. The observation from TEM image after photo-deposited Pt nanoparticles and DFT calculations verify the accumulation of electrons on some area of surface. The increased -NH2 groups significantly tune the electronic structure of g-C3N4 after modification. The generation of midgap state also affect the charge separation. Our reports provide a simple method to manage the migration of charge carriers and enables electrons directional transfer, which suppress the recombination and improve the photocatalytic activity.

Quantum chromodynamics (QCD) describes how mass is created at the quark level. This mechanism is special because the binding of quarks does not result in a mass loss or a release of energy, as in the case of the nuclear mass defect. Rather, mass is created by the binding of quarks. To achieve this binding, energy must be expended. At the same time, however, quarks are firmly bound to each other. Several authors have shown that the masses of the elementary particles as determined by means of QCD agree quite well with the experimentally determined values. In the following, superfine adjustment of the masses of the charged elementary particles is shown to be possible by considering the mass defect in terms of the mass-charge binding energy. &nbsp

When an extreme internal loading is applied to prestressed concrete (PSC) structures, serious property damage and human casualties may occur. However, the existing designs for PSC structures such as prestressed concrete containment vessels (PCCVs) do not include features to protect the structure from forces such as explosive blasts. Therefore, we evaluated the internal blast-resistance of PSC structures using blast tests on bi-directionally prestressed tubular concrete members. The goal of the study was to examine structural behavior data after an internal detonation. Explosive charges (ammonium nitrate – fuel oil; ANFO) were detonated at the center of the mid-span of the concrete tube with a standoff distance of 1000 mm. The data acquired included blast pressure, deflection, strain, crack pattern, and prestressing loss. The data were used to calculate the internal blast charge weight required to cause a PCCV to fail and to calibrate a simulation program to be used commercially for internal blast simulations at real scale structure.

Dominant frequency attenuation is a significant concern for frequency-based criteria of blasting vibration control. It is necessary to develop a concise and practical prediction equation describing dominant frequency attenuation. In this paper, a prediction equation of dominant frequency that accounts for primary parameters influencing the dominant frequency was proposed based on theoretical and dimensional analyses. Three blasting experiments were carried out in the Chiwan parking lot for collecting blasting vibration data used to conduct regression analysis of the proposed prediction equation. The fitting equations were further adopted to compare the reliability of three different types of dominant frequencies in the proposed equation and to explore the effects of different charge structures on the dominant frequency attenuation. The apparent frequency proved to be more reliable to express the attenuation law of the dominant frequency. The reliability and superiority of the proposed equation employing the apparent frequency were verified by comparison with the other five prediction equations. The smaller blasthole diameter or decoupling ratio leads to the higher initial value and corresponding faster attenuation of the dominant frequency. The blasthole diameter has a greater influence on the dominant frequency attenuation than the decoupling ratio does. Among the charge structures applied in the experiments, the charge structure with decoupling ratio of 1.5 and blasthole diameter of 48 mm results in the greatest initial value and corresponding fastest attenuation of the dominant frequency.

Hybridized local and charge-transfer (HLCT) excited-state fluorophores, which enable full exciton utilization through a reverse intersystem crossing from high-lying triplet states to singlet state,...

Quasi-two-dimensional (quasi-2D) perovskites with high stability usually suffers from poor device efficiency. Chemical tuning of the spacer cations has been an effective strategy to achieve efficient and stable quasi-2D perovskite solar cells. Here, we demonstrate that 3-halogon-substituted benzylammonium iodide (3X-BAI, X = F, Cl, Br, I) can significantly affect the orientation of low-dimensional perovskites and charge transport from perovskite to hole extraction layer, as well as device performance. With 3Br-BAI, we achieve the highest device efficiency of 13.21% for quasi-2D perovskites with a nominal n = 3 average composition. Our work provides a facile approach to regulate vertical crystal orientation and charge transport via tuning the molecular structure of organic spacer toward high performance quasi-2D perovskite solar cells.

The paper studies the radiation effects on the junction leakage random telegraph signal (JL-RTS). Using arrays of transistors, a statistical study of the phenomenon in MOSFETs source p-n junctions is performed and the impact of the electric field, the type of irradiation, and the source design is investigated. It appears that although JL-RTS originate both from the DDD- and TID-induced defects, the latter is the dominant contribution in MOSFETs sources due to an electric field enhancement. The paper then completes the study with ab initio molecular simulations to investigate the origin of the JL-RTS. The results advocate for the adoption of the structural fluctuation model over the state charge fluctuation model to describe the origin of the phenomenon.

Oxygen evolution cocatalysts (OECs) play important roles in improving the efficiency of photocatalysts in solar water splitting. Inorganic–organic hybrid polymers (IOHPs), which have good electroly...

Chemical corrosion and gamma‐ray irradiation appeared with the loss of coolant accident may seriously threaten the safe operation of a nuclear power plant, where epoxy resin (ER)‐based materials are widely used. It is urgent to study the effects of the corrosion and the irradiation on the electrical performance in an ER‐based nanocomposite. In this work, ER/Al2O3 nanocomposite samples with 0, 1, 3, 5‐wt% nano Al2O3 filler content were prepared at the thickness of 2 mm, and the total gamma irradiation dose was 0, 500, and 1000 kGy. The samples were chemically corroded in a boric acid solution (pH = 4.7) and a trisodium phosphate alkaline solution (pH = 11) at 60°C and 100°C for 48 h. Charge transport behaviour in the samples was derived from the surface potential decay method. In addition, the sample structures were characterised to analyse the corrosion mechanism in the solutions. The results indicated that the depth and the density of the trap showed a temperature‐dependent manner associated with the corrosion. With the addition of appropriate content of the filler, the trap centre was deepened and the carrier mobility was limited even after the corrosion. It is found that the appearance of hydroxyl and carboxyl groups during corrosion, the interaction between the nanoparticle and the matrix and the crosslinking reaction caused by the irradiation are responsible for the variation in charge transport behaviour.

In this paper, we consider the self-dual O ( 3 ) Maxwell-Chern-Simons-Higgs equations on a two-dimensional flat torus arising from the O ( 3 ) sigma gauge field model. Our main goal is to obtain the existence and uniqueness of topological solutions with vortices and antivortices. In order to achieve this goal, we show that the nondegeneracy of linearized operator for entire solution holds even when the symmetry is broken. Moreover, we also obtain the uniform bound of L 1 norm of nonlinearities with respect to large charge of electron. We expect that these results would play an significant role to get the asymptotic behavior of all possible solutions and count the total number of solutions.

The recombination of charge carriers arriving from the random charge movement in semiconductor photocatalysts greatly limits the practical application of solar-driven H2 evolution. The design of photocatalytic systems with spatially oriented charge-transfer is a promising route to achieve high charge-separation efficiency for photocatalysts. Herein, novel sea-urchin-like ReS2 nanosheet/TiO2 nanoparticle heterojunctions (SURTHs) are constructed. The unique sea-urchin-like structure endows the ReS2 cocatalyst with an unusual charge edge-collection effect, which leads to a significant acceleration of charge separation and transfer, as evidenced by the well-designed selective photodeposition of Pt quantum dots in SURTHs. The markedly improved charge transfer capacity contributes to a high photocatalytic H2 evolution rate of 3.71 mmol h−1 g−1 for SURTHs (an apparent quantum efficiency (AQE) of 16.09%), up to 231.9 times by contrast with that of P25 TiO2. This work would provide a new platform for designing the high-efficiency cocatalyst/photocatalyst system with excellent charge transfer capacity. This work was funded by the China Postdoctoral Science Foundation (pre-station, No. 2019TQ0050), Applied Basic Research Program of Sichuan Province (No. 2020YJ0068), the China Postdoctoral Science Foundation (No. 2020M673186), National Natural Science Foundation of China (No. 22002014), the Applied Basic Research Program of Sichuan Province (No. 2020ZYD014). Thanks for the technical help from Sichuan Province Key Laboratory of Display Science and Technology, State Key Laboratory of Electronic Thin Films and Integrated Devices. Dr. Xiao Luo acknowledges financial support from the National Natural Science Foundation of China (No. 21903084) and Applied Basic Research Program of Sichuan Province (No. 2021YJ0408). Dr. Qing Liu acknowledges financial support from the National Natural Science Foundation of China (No. 52002051) and the Fundamental Research Funds for the Central Universities, SCUT (No. ZYGX2020J009).

The process of cylinder charge – air sucked into the cylinder – transformation during engine start-up phase is characterized. Heat exchange and air flow through piston-cylinder group leakage processes are described as factors influencing the gas thermodynamic parameters. The Woschni formula based on similarity theory was finally used as equation describing heat transfer in combustion engines cylinder. The computational model for cylinder charge parameters in the whole engine cycle during its starting at low temperature is presented. Some taken assumptions and characteristics of partial processes resulting from the computations are shown. There are indicated the possibilities of using the model at internal combustion engine diagnostic process.

Electronic coupling between individual building blocks plays an essential role in charge transport through molecular materials and devices. However, the investigation of the transmission mechanism ...

The separation, transfer and recombination of charge often affect the rate of photocatalytic reduction of CO2. Schottky junctions can promote the rapid separation of space charge. Therefore, in this paper, Pd nanosheets were grown on the surface of DUT-67 by a hydrothermal method, and a Schottky junction was constructed between DUT-67 and Pd. Under the action of the Schottky junction, the CO yield of 0.3-Pd/DUT-67 reached 12.15 μmol/g/h, which was 17 times higher than that of DUT-67. Efficient charge transfer was demonstrated in photochemical experiments. The large specific surface area and the increased light utilization rate also contributed to the increase in the CO2 reduction efficiency. In addition, the mechanism of Pd/DUT-67 photocatalytic reduction of CO2 was proposed.

Three-body $AAB$ model for the $NN{\bar K}(s_{NN}=0)$ kaonic cluster is considered based on the configuration space Faddeev equations. Within a single-channel approach, the difference between masses of nucleons and kaons and the charge independence breaking of nucleon-nucleon interaction are taken into consideration. We definite the particle configurations in the system according to the particle masses and pair potentials. There are two sets of the particle configurations, $ ppK^-$, $np \bar{K^0}$ and $nn {\bar K}^0$, $npK^-$, charged and neutral. The three-body calculations are performed by applying $NN$ and $N\bar K$ phenomenological isospin-dependent potentials. The mass and energy spectra related to the particle configurations are presented. We evaluate the mass and energy uncertainties for the $NN\bar K$ model. An analogy to $NNN$ model for the $^3$H and $^3$He nuclei is proposed.

The space charge dynamic behavior and accumulation are important contributions to the formation of electrical trees, as recognized by crosslinked polyethylene (XLPE) cable insulation under alternating current electric stress. In this paper, in order to investigate the reasons for the charge accumulation phenomenon revealed by experiments under ac stress, a bipolar space charge transport model with symmetrical and asymmetrical parameters is built under AC stress. The charge accumulation mechanism is analyzed based on the variation of space charge density with different voltage application time and voltage phase. The effects of each major physical parameter are simulated and analyzed, respectively. The results show that there is no obvious space charge accumulation with the transport model under symmetrical physical parameters. However, asymmetrical parameters in the transport model result in different motions between positive and negative charges, which greatly enhances the charge accumulation. Each main parameter has an influence on charge accumulation in different perspectives and extents. The applicability of the simulation model with asymmetrical parameters is evaluated by comparing experiment and simulation results. This study contributes to the understanding of space charge generation mechanism under AC voltage and serves as a basis for improving the stability of XLPE electric power cables.

There is an urgent need to develop a robust capacitor charge power supply (CCPS) system to meet the requirement of pulsed load in all‐weather mobile occasions such as vehicle, ship and aircraft. Brushless doubly fed alternator (BDFA) works through the rotor's pole pairs' transformation to get excitation indirectly, without magnets, brushes and slip rings. Both DC and AC excitation can be used. Therefore, it has high reliability and a good application prospect in the CCPS system. However, the existing research studies lack analysis of the parameters that affect charging performance, and have no experimental analysis of the prototype. To solve this problem, a comprehensive design method and experimental procedure of the pulsed BDFA are proposed and investigated. First, the operation principle of the pulsed BDFA is illustrated. Then, the charging performances under different design schemes are comparatively analysed through the finite element analysis (FEA). Finally, a prototype of the pulsed BDFA is manufactured, and the related experiments are carried out. The results verify the feasibility of the experimental procedure and the accuracy of FEA. The comprehensive design method and experimental procedure in this work provide a straightforward reference for the subsequent applications in the CCPS system.

We investigate the nonlinear dynamics of a DNA molecule system by using the Peyrard-Bishop model. The PB model brings out the charge transport in DNA with the influence of twisting and we detect the regions of instability through the linear stability analysis. There are two regimes where the modulated charge patterns can occur under twisted and also the over twisted conformations. Numerical simulations confirm our analytical predictions. We conclude that, when the DNA molecule is over twisted and in the absence of twisting, the system may lead to the breaking of the hydrogen bond between base pairs.

Monolayer molybdenum di-selenide (1L-MoSe2) stands out in the transition metal dichalcogenide family of materials as an outlier where optical generation of valley polarization is inefficient. Here we show that using charge doping in conjunction with an external magnetic field, the valley polarization of 1L-MoSe2 can be controlled effectively. Most remarkably, the valley polarization can be tuned to negative values, where the higher energy Zeeman mode emission is more intense than the lower energy one. Our experimental observations are interpreted with valley-selective exciton-charge dressing that manifests when gate induced doping populates predominantly one valley in the presence of Zeeman splitting.

Several approaches have recently been investigated with the aim of enhancing the specific capacitance of polyaniline (PANI). We herein report a novel pathway to boost the specific capacitance of PANI, which is highly tunable and versatile, based on wet chemistry techniques. In this approach, utilization of a specific metal-organic framework (MOF), UiO-66-NH2, as a nanopore generator (Nanogen) is demonstrated. This systematic study demonstrates a tight interplay between the enhanced electrolyte accessibility to the PANI chains, through the incorporation of MOF nanogens, and the optimal relative amount of the conductive PANI, necessary to attain a charge percolation threshold in the binary system (MOF@PANI). Satisfying the charge percolation while maintaining porosity is necessary to arrive at a maximized specific capacitance of the PANI as the active phase. The enhancement in the specific capacitance of the PANI was fully exploited through a systematic investigation that helped to pinpoint the saddle point at which the two orthogonal properties, namely porosity (electrolyte diffusivity) and charge mobility (PANI inter-chain electronic conductivity) can be fine-tuned via controlling the materials composition. Of the different compositions investigated, the composite containing 23 wt% PANI of the total weight, doped with MOF nanogens, resulted in an enhanced specific capacitance of 872 F g-1 for the PANI, in comparison to only 469 F g-1 for the pristine PANI investigated under identical conditions.

The charge distributions and elastic electron form factors for 18O, 42,44Ca, 58Ni, and 118Sn nuclei were considered using the cluster expansion of the 1- and 2-body terms. Inelastic electron form factors to 2+ states with core-polarization effects were studied, where the nuclear collective modes were considered alongside the shell model transition density. The influence of short-range correlations (SRCs) was calculated by the parameter β, which was introduced into the ground-state charge distribution and concluded the Jastrow-type function. It is found that the inclusion of 2-body correlations is necessary to describe the observed data of elastic and inelastic form factors at high momentum transfer q > 3 fm–1.

The advancement in synthesis techniques provide the opportunity to synthesis the sample with uniform size, desired morphology and enhanced property for specific application. The role of semiconductor in various optoelectronic, spintronics and memory device has been approved by available literature. The emergence of semiconductor quantum dot opens new possibility to improve the performance of semiconductor-based device as well as new application due to quantum confinement phenomenon. The confinement of charge carries leads toward the tuning of electrical conductivity, band gap and magnetic nature of semiconductor. This work is focused on study of CdSe and CdTe semiconductor quantum dot and corresponding change in their properties by quantum confinement. The applications along with different dopant ion have been summarised through table and supported by literature.

In Part I, an electrification scheme was described and a simulation of an observed cold-based storm from the U.S. Great Plains was validated with electrical observations. Most charge in the storm was separated by rebounding collisions of secondary ice originating from prior graupel–snow collisions. In this Part II, sensitivity tests are performed with the control simulation (Part I) and influences from environmental factors (aerosols, temperature, moisture, and shear) on lightning are elucidated. Environmental factors [e.g., convective available potential energy (CAPE)] controlling updraft speed are salient. When ascent is reduced by 30% and 70%, flashes become 70% fewer and disappear, respectively; faster ascent promotes positive cloud-to-ground (+CGs) flashes. Since cloud base is too cold (1°C) for coalescence, cloud condensation nucleus aerosol concentrations do not influence the lightning appreciably. The electrical response to varying concentrations of active ice nuclei is limited by most ice particles being secondary and less sensitive—a natural “buffer.” Imposing a maritime sounding suggests that the land–sea contrast in lightning for such storms is due to the vertical structure of environmental temperature and humidity. Weak CAPE, and both entrainment and condensate weight from a low cloud base, suppress ascent and charging. Maritime thermodynamic conditions reduce simulated flash rates by two orders of magnitude. Reducing aerosol loadings from continental to maritime only slightly reinforces this suppression. Last, a conceptual model is provided for how any simulated storm is either normal because graupel/hail is mostly positively charged or else is inverted/anomalous because graupel/hail is mostly negatively charged, with environmental factors controlling the charging. Impacts from microphysical processes, including three processes of secondary ice production, on lightning are analyzed.

Understanding the structure–property relationships in antiaromatic molecules is crucial for controlling their electronic properties and designing new organic optoelectronic materials. Here we report the design, synthesis, and characterization of three new antiaromatic molecules (Pn, n = 1–4) based on the pentalene (P) antiaromatic core, to investigate how electron-donating and electron-accepting substituents affect P1–P4 properties. As expected, the optical, HOMO and LUMO energy levels and electronic structure are greatly modulated by core substitution. Compared to the unsubstituted compound (P1), P3 and P4 containing strong electron-withdrawing units reduced antiaromaticity as assessed by nucleus-independent chemical shift (NICS) calculations compared with P2, which is functionalized with strong electron-donating units, showing that substitution strongly tunes local antiaromaticity. Organic field-effect transistors (OFETs) fabricated using these materials indicate that P2 has an average hole mobility of ∼10−4 cm2 V−1 s−1 while P3 has an average electron mobility of up to 0.03 cm2 V−1 s−1, versus FET-inactive P1. Therefore, introduction of strong π-extended electron-withdrawing or electron-donating substituents onto an antiaromatic core is an effective strategy to switch-on charge transport capacity.

5,15-Bis(triisopropylsilyl)ethynyltetrabenzoporphyrin (TIPS-H2BP) gave a one-dimensionally extended columnar packing motif. The single crystal field-effect transistor of TIPS-H2BP exhibited clearly better hole mobility (2.16 cm2 V−1 s−1) than its metal complexes (ca. 0.1 cm2 V−1 s−1), with efficient charge transport through π–π stacking along the tetrabenzoporphyrin units.

This work addresses the issue of dark states formation in QDs by cooperative excitonic and intrinsic defect-assisted radiative transitions. Here we refer to the observed blinking as D-type to distinguish it from purely excitonic types. It is shown experimentally that defect-assisted radiative relaxations in a single I-III-VI QD result in atypical blinking characteristics that cannot be explained on the basis of charged exciton models. In addition to the excitonic channel, it has been proposed that defect-assisted kinetics can also form blinking patterns. Two conditions for the formation of dark states have been identified which are related to correlation and competition when considering photons emitted from bright defects. Two transition schemes have therefore been proposed. The first transition scheme includes time-correlated trapping of more than one electron at a single trap centre. This is used to simulate variations in the defect's charge state and switching between radiative/nonradiative transitions. The latter scheme, on the other hand, involves uncorrelated trapping and radiative relaxations from two different types of defects (competition). Both schemes are seen to play an equal role in radiative processes in I-III-VI QDs. Considered together, the proposed models can reflect the experimental data with very good accuracy, providing a better understanding of the underlying physics. An important implication of these schemes is that dark states formation doesn't have to be limited to mechanisms that involve charged excitons, and it may also be observed for independent defect assisted kinetics. This is especially valid for highly defected or multinary QDs.

The interfacial charge transfer (CT) that plays an important role in enhancing the photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs) has not always been fully explored. Here, TiO2@N719@Ag DSSCs system was constructed, and the CT processes have been monitored by surface-enhanced Raman scattering (SERS) spectra. Meanwhile, it is well known that as one of the most common external stimulis, high pressure can increase the free carrier density of TiO2 NPs and cause the band gap to narrow. In the high pressure SERS experiment, we observed a significant enhancement of N719 dye in the TiO2@N719@Ag system up to 2.48 GPa, which is consistent with the variation trend of charge transfer degree (ρCT). It is indicated that band gap changes will strongly affect the CT process, further influence the SERS signal intensity (or ρCT), and thus increase the CT probability of DSSCs. Futhermore, the decoration of Ag NPs in the TiO2@N719@Ag DSSCs system can introduce localized surface plasmon resonance (LSPR), enhance the light trapping ability and offer additional CT pathways. Importantly, it is possible to improve the photoelectric conversion performance of DSSCs via high pressure method and the introducing of Ag NPs. Finally, in order to observe the CT process of DSSCs more clearly, the models describing the CT mechanism have been proposed. SERS spectroscopy is expected to be a promising technique for the exploration of the interfacial CT behavior in DSSCs devices, which may further broaden the thoughts of improvement of efficiency of cells.

Simply adding ITIC derivatives, which can form a cascade energy alignment between the host donor and acceptor LUMO levels, as a small amount (5 wt%) of A2 acceptor molecules in TOSCs improved the PCE by up to 10% more than that of the BOSC system.