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Background/Objectives: It is often challenging for patients to understand treatment options, their mechanisms of action, and the potential side effects of each treatment option for glomerular disorders. This study explored the ability of ChatGPT to simplify these treatment options to enhance patient understanding. Methods: GPT-4 was queried on sixty-seven glomerular disorders using two distinct queries for a general explanation and an explanation adjusted for an 8th grade level or lower. Accuracy was rated on a scale of 1 (incorrect) to 5 (correct and comprehensive). Readability was measured using the average of the Flesch–Kincaid Grade (FKG) and SMOG indices, along with the Flesch Reading Ease (FRE) score. The understandability score (%) was determined using the Patient Education Materials Assessment Tool for Printable Materials (PEMAT-P). Results: GPT-4's general explanations had an average readability level of 12.85 ± 0.93, corresponding to the upper end of high school. When tailored for patients at or below an 8th-grade level, the readability improved to a middle school level of 8.44 ± 0.72. The FRE and PEMAT-P scores also reflected improved readability and understandability, increasing from 25.73 ± 6.98 to 60.75 ± 4.56 and from 60.7% to 76.8% (p < 0.0001 for both), respectively. The accuracy of GPT-4's tailored explanations was significantly lower compared to the general explanations (3.99 ± 0.39 versus 4.56 ± 0.66, p < 0.0001). Conclusions: ChatGPT shows significant potential for enhancing the readability and understandability of glomerular disorder therapies for patients, but at a cost of reduced comprehensiveness. Further research is needed to refine the performance, evaluate the real-world impact, and ensure the ethical use of ChatGPT in healthcare settings. [ABSTRACT FROM AUTHOR]

The small molecule built around the benzene ring, diacetyl phenylenediamine (DAPA), has attracted much attention due to its synthesis accessibility, large Stokes shift, etc. However, its meta structure m-DAPA does not fluoresce. In a previous investigation, it was found that such a property is due to the fact that it undergoes an energy-reasonable double proton transfer conical intersection during the deactivation of the S1 excited-state, then returns to the ground state by a nonradiative relaxation process eventually. However, our static electronic structure calculations and non-adiabatic dynamics analysis results indicate that only one reasonable non-adiabatic deactivation channel exists: after being excited to the S1 state, m-DAPA undergoes an ultrafast and barrierless ESIPT process and reaches the single-proton-transfer conical intersection. Subsequently, the system either returns to the keto-form S0 state minimum with proton reversion or returns to the single-proton-transfer S0 minimum after undergoing a slight twist of the acetyl group. The dynamics results show that the S1 excited-state lifetime of m-DAPA is 139 fs. In other words, we propose an efficient single-proton-transfer non-adiabatic deactivation channel of m-DAPA that is different from previous work, which can provide important mechanistic information of similar fluorescent materials. [ABSTRACT FROM AUTHOR]

The objective of this study is to explore the influence of proteins type and antioxidants on the physicochemical properties, in vitro digestion, and bioaccessibility of β‐carotene laden emulsions. The combination of rutin and whey protein isolate provides optimal bioaccessibility while also stabilizing the emulsion system and effectively preventing β‐carotene degradation. This is due to the amphiphilic rutin adsorbed into the interface of the emulsion stabilized by whey protein, resulting in partially replacing and further improving the physical and oxidative stability of the β‐carotene emulsion. Meanwhile, the rutin emulsions remain stable and carotene content is still higher (22.38–32.07%) than others even after digestion. Hence, these emulsions show great potential to be applied for delivering β‐carotene based on oil‐in‐water emulsions. This study provides valuable information to build up stable excipient emulsions for functional foods and nutraceuticals. Practical applications: β‐carotene is being exploited for a range of biomedical applications. Concentrate on the blend of antioxidants and proteins displaying various properties in β‐carotene O/W emulsions that can more likely convey β‐carotene to the body and better keep up with natural movement. [ABSTRACT FROM AUTHOR]

Over the last few decades, conical intersections (CoIns) have grown from theoretical curiosities into common mechanistic features of photochemical reactions, whose function is to funnel electronically excited molecules back to their ground state in regions where the potential energy surfaces (PESs) of two electronic states become degenerate. Analogous to transition states in thermal chemistry, CoIns appear as transient structures providing a kinetic bottleneck along a reaction coordinate. However, such a bottleneck is not associated with the probability of crossing an energy barrier but rather with an excited state decay probability along a full "line" of transient structures connected by non-reactive modes, the intersection space (IS). This article will review our understanding of the factors controlling CoIn mediated ultrafast photochemical reactions, taking a physical organic chemist approach by discussing a number of case studies for small organic molecules and photoactive proteins. Such discussion will be carried out by first introducing the "standard" one-mode model based on Landau–Zener (LZ) theory to describe a reactive excited state decay event intercepting, locally, a single CoIn along a single direction, and then by providing a modern perspective based on the effects of the phase matching of multiple modes on the same local event, thus redefining and expanding the description of the excited state reaction coordinate. The direct proportionality between the slope (or velocity) along one mode and decay probability at a single CoIn is a widely applied fundamental principle that follows from the LZ model, yet it fails to provide a complete understanding of photochemical reactions whose local reaction coordinate changes along the IS. We show that in these situations, in particular by focussing on rhodopsin double bond photoisomerization, it is mandatory to consider additional molecular modes and their phase relationship approaching the IS, hence providing a key mechanistic principle of ultrafast photochemistry based on the phase matching of those modes. We anticipate that this qualitative mechanistic principle should be considered in the rational design of any ultrafast excited state process, impacting various fields of research ranging from photobiology to light-driven molecular devices. [ABSTRACT FROM AUTHOR]

We study the dynamics of flow over a flexible cantilever beam and explore the effect of the plasma actuators located at the upper and lower end edges of the beam to control the flow-induced vibration of the beam. For this purpose, three-dimensional simulations are performed at various Reynolds numbers for three cases including simple beam, beam without the plasma actuators, and beam with the plasma actuators. The results show that in comparison with the simple beam, the beam with the plasma actuators reduces the displacement of the tip by 33% and 18% at Reynolds numbers Re = 200 and 300, respectively. The plasma actuators cause a monotonic oscillation and a regular vortex street with reducing the strength of the formed vortex and increase the bending of the beam. The presence of the plasma actuators at the free end of the beam reduces the root mean square lift coefficient by 32.8% at Re = 200 and 5.6% at Re = 300. Although the parameters of the plasma actuators for the upper and lower actuators are constant, by changing the position of the free end of the beam, the velocity profiles will be different and depend on the structural flexibility and flow regime. [ABSTRACT FROM AUTHOR]

A valence bond (VB) block-diagonalization approach, named VBBDA, is proposed to construct the charge-localized diabatic state explicitly within the framework of ab initio VB theory. Since the VB structure built upon the localized orbitals represents the charge localized character of the diabatic state faithfully, we are able to obtain accurate electronic coupling between diabatic states by using a very compact VB wave function. Moreover, the potential energy curves of the diabatic states and hence the crossing points of them can be accurately evaluated. The pilot applications showed that the electronic couplings computed by the VB method are consistent with the complete active space self-consistent field method and may even be close to the results of other high-level ab initio methods such as full configuration interaction and multireference configuration interaction. In addition, the computed electronic couplings show the expected exponential attenuation for the donor-acceptor systems as the distance increases. Moreover, VBBDA has the capability for handling complicated systems based on either two-state or multi-state treatment. Finally, because of the outstanding performance of the Xiamen Valence Bond software package, which is an ab initio VB program, VBBDA is capable for systems consisting more than 1000 basis functions. [ABSTRACT FROM AUTHOR]

The photochemistry of numerous molecular systems is influenced by conical intersections (CIs). These omnipresent nonadiabatic phenomena provide ultra-fast radiationless relaxation channels by creating degeneracies between electronic states and decide over the final photoproducts. In their presence, the Born–Oppenheimer approximation breaks down, and the timescales of the electron and nuclear dynamics become comparable. Due to the ultra-fast dynamics and the complex interplay between nuclear and electronic degrees of freedom, the direct experimental observation of nonadiabatic processes close to CIs remains challenging. In this article, we give a theoretical perspective on novel spectroscopic techniques capable of observing clear signatures of CIs. We discuss methods that are based on ultra-short laser pulses in the extreme ultraviolet and X-ray regime, as their spectral and temporal resolution allow for resolving the ultra-fast dynamics near CIs. [ABSTRACT FROM AUTHOR]

Summary: The changes in gel characteristics, rheology and antioxidant properties, microstructure and water mobility were studied to investigate the potential use of flaxseed oil double emulsion to replace pork back‐fat (25%, 50%, 75% and 100%) in reduced‐fat pork batter. The flaxseed oil double emulsion (pH 6.0) was made of 20 mL 0.5% tea polyphenol solution (w/w), 20 mL flaxseed oil, 60 mL 4% whey protein (w/w) and 400 mL 2% Arabic gum solution. The result showed that the TBARS, L*, and a* values of pork batter significantly decreased (P < 0.05) when the flaxseed oil double emulsion replacing the pork back‐fat was ≤50%. Meanwhile, the pH, emulsification stability, hardness, springiness, gumminess, chewiness, cooking yield and G′ at 80 °C significantly increased (P < 0.05). In addition, the mobility of water in cooked batter first decreased and then increased (P < 0.05) with increasing flaxseed oil double emulsion. In addition, the microstructure of cooked pork batter with 50% flaxseed oil double emulsion has a continuous, tighter and regular structure, with the pores being smaller and more uniform. Overall, the replacement of pork back‐fat with flaxseed oil double emulsion at 50% reduced‐fat content could improve the quality of pork batter. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge plasma actuators (DBD-PAs) are deployed experimentally for the first time in a feed-forward proportional-derivative (PD) control system, where the fluctuating wall-pressure Pw is demonstrated to be an effective feed-forward signal, to manipulate a turbulent boundary layer for drag reduction. A floating-element force balance with an area of 50 mm (streamwise length) × 200 mm (spanwise length) is deployed to capture the spatially averaged drag variation behind the DBD-PAs. The DBD-PAs generate streamwise vortices, whose occurrence synchronizes with the output signal of the controller with a predominant frequency of 40 Hz under the optimally tuned PD control. The control system proves to be effective, achieving a spatially averaged drag reduction by 16%, and efficient, cutting down its energy consumption by 30% at a negligibly small expense of drag reduction compared with the open-loop control. It has been found that the optimally tuned PD control aptly increases the voltage applied to the DBD-PAs upon detecting large Pw fluctuations or coherent structures, accounting for the savings in input power, Pinput. The experimental data have been carefully analyzed, which cast light upon the underlying physical mechanism behind the drag reduction. The reason behind the efficient control is also clearly elaborated. [ABSTRACT FROM AUTHOR]

We analyze two approaches to the quantum-classical Liouville (QCL) formalism that differ in the order of two operations: Wigner transformation and projection onto adiabatic electronic states. The analysis is carried out on a two-dimensional linear vibronic model where geometric phase (GP) effects arising from a conical intersection profoundly affect nuclear dynamics.We find that theWignerthen- Adiabatic (WA) QCL approach captures GP effects, whereas the Adiabatic-then-Wigner (AW) QCL approach does not. Moreover, the Wigner transform in AW-QCL leads to an ill-defined Fourier transform of double-valued functions. The double-valued character of these functions stems from the nontrivial GP of adiabatic electronic states in the presence of a conical intersection. In contrast, WA-QCL avoids this issue by starting with the Wigner transform of single-valued quantities of the full problem. As a consequence, GP effects in WA-QCL can be associated with a dynamical term in the corresponding equation of motion. Since the WA-QCL approach uses solely the adiabatic potentials and non-adiabatic derivative couplings as an input, our results indicate that WA-QCL can capture GP effects in two-state crossing problems using first-principles electronic structure calculations without prior diabatization or introduction of explicit phase factors. [ABSTRACT FROM AUTHOR]

In molecular systems containing conical intersections (CIs), a nontrivial geometric phase (GP) appears in the nuclear and electronic wave functions in the adiabatic representation. We study GP effects in nuclear dynamics of an N-dimensional linear vibronic coupling (LVC) model. The main impact of GP on low-energy nuclear dynamics is reduction of population transfer between the local minima of the LVC lower energy surface. For the LVC model, we proposed an isometric coordinate transformation that confines non-adiabatic effects within a two-dimensional subsystem interacting with an N - 2 dimensional environment. Since environmental modes do not couple electronic states, all GP effects originate from nuclear dynamics within the subsystem. We explored when the GP affects nuclear dynamics of the isolated subsystem, and how the subsystem-environment interaction can interfere with GP effects. Comparing quantum dynamics with and without GP allowed us to devise simple rules to determine significance of the GP for nuclear dynamics in this model. [ABSTRACT FROM AUTHOR]

I present a new formulation of wave-packet spawning procedure based on a second order perturbation theory expression for population transfer between different diabatic electronic states. The employed perturbation theory (PT) expansion is based on an assumption that diabatic states can be represented locally with their Taylor series up to quadratic terms in nuclear coordinates (local harmonic approximation). The corresponding local harmonic basis of vibrational states makes infinite summation over excited states in PT expressions possible, and thus, it provides a complete basis set expression for the population transfer. This allows me to detect when a finite basis set expansion employed in variational wave packet propagation does not adequately describe the interstate population transfer. Also, it suggests a rigorous criterion for basis set expansion (spawning). The proposed procedure is illustrated for the variational multiconfigurational Gaussian wave packet method applied to 1D and 2D model examples, and it also can be extended to direct on-the-fly dynamics with any Gaussian wave packet propagation method. [ABSTRACT FROM AUTHOR]

This paper presents the results of numerical simulation of a dielectric barrier discharge (DBD) plasma actuator and shows its effectiveness to control air flow around the NACA(National Advisory Committee for Aeronautics)0015 airfoil. The actuator consists of two tape electrodes separated by a dielectric layer, and it is mounted on the suction side of the airfoil at 18% of the chord length. An alternating voltage with 20 kV magnitude and 10 kHz frequency is applied between both electrodes. The physical model of the DBD includes the drift of two ionic species, positive and negative, and the Poisson equation for the electric potential distribution. The spatio-temporal distribution of the electric field, the space charge density in the ambient air, and the surface charge density on the dielectric layer have been determined. The time average electric body force was entered into the air flow model, which was solved using the Spalart–Allmaras turbulence technique. The simulation of the air flow was performed for the free-stream velocities between 5 m/s and 20 m/s (Reynolds numbers 1.65 × 105–6.61 × 105 based on the chord length). The results of computations show the effect of the electrohydrodynamic actuation on the flow pattern, the lift and drag coefficients, the pressure coefficient, and the flow fluctuation near the airfoil. The ability of the DBD actuation to effectively control the aerodynamic airfoil characteristics has been confirmed, and its limitations for the discussed case have been determined. [ABSTRACT FROM AUTHOR]

Plasma actuator is a flow control device to improve the aerodynamic performance of wind turbine blades at low airspeeds. One of the most robust numerical models for simulation of plasma actuator interaction with the fluid flow is the electrostatic model. This model is improved recently and is extensively verified by the authors. Due to the high cost of performing experimental optimizations, the optimized geometrical dimensions and materials of a plasma actuator may be sought by this numerical model. The aim of the present study is the aerodynamic enhancement of a DU21 wind turbine blade airfoil in which the effect of geometric parameters and the dielectric material is examined separately. The examined parameters include the dielectric thickness and material, the electrode thickness, and the embedded electrode length. This study shows that for performance improvement, there is a certain limit for each parameter. The length of the embedded electrode and the dielectric permittivity have a maximum limit, after which increasing the values of these parameters does not significantly affect the performance of the actuator. The increase in both the electrode thickness and the dielectric thickness reduces the effect of the actuator, and after increasing to a certain extent, no significant extra effect on the actuator performance is seen. These results also show that the improved electrostatic model can be used as a powerful tool to model the effects of different parameters to find an optimum blade design. [ABSTRACT FROM AUTHOR]

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We consider photoinduced electronic transitions through conical intersections in large molecules. Starting from the linear vibronic model Hamiltonian and treating linear diabatic couplings within the second order cumulant expansion, we have developed a simple analytical expression for the time evolution of electronic populations at finite temperature. The derived expression can be seen as a nonequilibrium generalization of the Fermi golden rule due to a nonequilibrium character of the initial photoinduced nuclear distribution. All parameters in our model are obtained from electronic structure calculations followed by a diabatization procedure. The results of our model are found to agree well with those of quantum dynamics for a test set of systems: fulvene molecule, 2,6-bis(methylene) adamantyl cation, and its dimethyl derivative. [ABSTRACT FROM AUTHOR]

Charge transfer processes within stacked π-systems were examined for the stacked ethylene dimer radical cation with inclusion of a bridge containing up to three formaldehyde molecules. The electronic structure was treated at the complete active space self-consistent field and multireference configuration interaction levels. Nonadiabatic interactions between electronic and nuclear degrees of freedom were included through semiclassical surface hopping dynamics. The processes were analyzed according to fragment charge differences. Static calculations explored the dependence of the electronic coupling and on-site energies on varying geometric parameters and on the inclusion of a bridge. The dynamics simulations gave the possibility for directly observing complex charge transfer and diabatic trapping events. [ABSTRACT FROM AUTHOR]

Phtalocyanine compounds deserved a considerable interest in recent times, particularly because of their possible use in the field of nanoelectronics. In particular, the charge mobility (of both electrons and holes) in phtalocyanine stacked arrangements has been recently extensively investigated. The present work focuses on the study of the hole-transfer mechanism between two phtalocyanine monomers. For an interdisk distance larger than 4.5 bohrs, the eclipsed dimer exhibits a mixed-valence behavior, with a saddle point transition state separating two equivalent minima. This behavior, however, is strongly dependent on the relative angle between the disks. In particular, the mixed-valence character of the compound is strongly enhanced for arrangements that are far from the eclipsed geometry. Moreover, for values of the angle close to π/8 and 3π/8, the ground and excited transition states have exactly the same energy, thus implying the presence of a conical intersection. These results can have deep implication in the charge transfer along phtalocyanine chains. [ABSTRACT FROM AUTHOR]

The photophysics of the perylene radical cation (Pe•+) was studied using the molecular mechanics-valence bond (MMVB) hybrid force field. Potential energy surfaces of the first three electronic states were investigated. Geometry optimizations of critical points—including conical intersections between the relevant electronic states—were performed using the MMVB analytical energy gradient for cations. No accessible planar conical intersection between the D0 and D1 states of Pe•+ was found; this is consistent with the experimentally observed D1 lifetimes and the observation of D1 emission from this cation in the condensed phase. Benchmark RASSCF and TD-DFT calculations support the reliability of the MMVB results. [ABSTRACT FROM AUTHOR]

An iterative method based on the density matrix block diagonalization has recently been proposed. It includes part of the dynamical correlation in the orbital optimization process and provides either localized or delocalized symmetry adapted molecular orbitals. The present work compares the so-obtained orbitals with the orbitals given by the traditional energy minimization process. Both analytical derivations and numerical calculations on model systems show that the self-consistent field symmetry-breaking problem is avoided when using the density matrix-based procedure in the case of states presenting a left–right resonance, such as mixed valence compounds or bichromophoric molecules. Accurate calculations of excitation energies in a family of magnetic systems, which generally require highly correlated treatments, can also be obtained at a low computational cost when using these appropriate orbitals. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present a method that uses the one-particle density matrix to generate directly localized orbitals dedicated to multireference wave functions. On one hand, it is shown that the definition of local orbitals making possible physically justified truncations of the CAS (complete active space) is particularly adequate for the treatment of multireference problems. On the other hand, as it will be shown in the case of bond breaking, the control of the spatial location of the active orbitals may permit description of the desired physics with a smaller number of active orbitals than when starting from canonical molecular orbitals. The subsequent calculation of the dynamical correlation energy can be achieved with a lower computational effort either due to this reduction of the active space, or by truncation of the CAS to a shorter set of references. The ground- and excited-state energies are very close to the current complete active space self-consistent field ones and several examples of multireference singles and doubles calculations illustrate the interest of the procedure. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increase in the number of research papers on plasma and its use in active flow control applications. The main objective of this study is to assess the plasma actuator's position on a NACA0015 airfoil in terms of aerodynamic forces. In addition, optimization of the plasma actuator's position and its configuration are studied in order to identify the optimum configuration for improvement in lift coefficient. The experiments are conducted in an open‐suction‐type wind tunnel at Reynolds numbers of 48,000, 75,000, and 100,000. The plasma actuators are mounted on various positions (x/C) starting from the leading edge to trailing edge of the airfoil. The experimental results on aerodynamic force measurement are presented to illustrate the increasing lift effect of the generated plasma. It is also shown that the plasma actuators used as an active flow control device appears to shift the stall angle of the airfoil. The results of the experimental study suggest that the energy efficiency of airborne systems can be improved with the use of plasma actuators due to its increasing lift coefficient effect. This result becomes a vital finding considering that the same flight can be achieved with less fuel and less amount of environmental pollution for the same distance of journey. It is also worth mentioning that increasing lift effect would mean taking off from a shorter runway or allowing the airborne vehicle with the ability to fly with additional payload. [ABSTRACT FROM AUTHOR]

We conduct large-eddy simulations of separated airfoil flows with control by a dielectric-barrier-discharge plasma actuator over a wide range of Reynolds numbers. The Reynolds numbers based on the chord length (Re) are set at Re = 5.0 × 103, 1.0 × 104, 6.3 × 104, 2.6 × 105, and 1.6 × 106. These Reynolds numbers cover most of the conditions used in the previous studies on separation control by a plasma actuator. The burst frequency nondimensionalized by the chord length and freestream velocity (F+) is used as the computational parameter, and the effective burst actuation and control mechanisms at each Reynolds number condition are investigated. With regard to cases without the control, the flows separate near the leading edge in the laminar state at the Reynolds number range of 103–105, and a substantial turbulent separation occurs at the Reynolds number of 1.6 × 106. Separation control with a high burst frequency [F+ ≃ O(10)] can cause early flow reattachment through the promotion of turbulent transition of a separation shear-layer for Re = 6.3 × 104 and 2.6 × 105. Flow reattachment is mainly caused by momentum entrainment into the boundary layer by fine-scale turbulent vortices. On the other hand, the large-scale spanwise vortices play an important role at F+ = 1 for Re = 1.0 × 104 and 1.6 × 106. In these cases, the dynamics of the spanwise vortices show similar behavior and the pairing of these vortices significantly contributes to the separation control by increasing the momentum entrainment. The optimum value of F+ changes with a Reynolds number. In contrast, when a nondimensional burst frequency based on the characteristics of the separation shear-layer ( F θ s ) is considered, a high lift-to-drag ratio is found at F θ s ≃ O (1 0 − 2 ) for all Reynolds numbers. This demonstrates that one of the effective burst frequencies is closely related to the scale of the separation shear-layer, especially for the spanwise vortex shed from the separation shear-layer. [ABSTRACT FROM AUTHOR]

In the present study, a new method for extraction and preconcentration of amoxicillin and ceftriaxone was used in hospitalised sewage samples, called vortex-assisted liquid-phase microextraction based on the solidification of deep eutectic solvent. Samples were analysed by high-performance liquid chromatography-ultraviolet detection after preparation and extraction. In this method, the new deep eutectic solvent is used as the extraction solvent, which is obtained from the combination of 1-decyl-3-methylimidazolium chloride and n-butanoic acid. The important advantages of this novel extraction solvent include material stability, low density and good freezing point near room temperature. Under the optimum conditions, enrichment factors are in the range of 164-172. Repeatability and reproducibility of the method based on seven replicate measurements of 50.0 µg L−1 of the target analytes in analysed samples were in the range of 2.1-3.5% and 3.8-5.2%, respectively. The limit of detections and linearity are in the range of 0.005-0.10 and 3-600 µg L−1, respectively. The method was successfully applied for the determination of amoxicillin and ceftriaxone in the real sewage samples. The relative recoveries of sewage samples spiked with amoxicillin and ceftriaxone are 91-107%. [ABSTRACT FROM AUTHOR]

A topological or geometric phase (GP) blockade can be introduced in molecular electron transfer processes if a conical intersection (CI) occurs between two charge configurations. The origin of the blockade is in the destructive interference of two pathways around the CI that acquire opposite GPs. Electron transfer quantum dynamics including and excluding GP have been modelled for the bis(methylene) adamantyl carbocation. These calculations have shown unambiguously that the CI topology and the induced GP are responsible for the transport blockade. [ABSTRACT FROM AUTHOR]

With the aim of detecting glutaraldehyde (GA) in wastewater released from hospitals and other sites, fluorescent poly(phenyleneethynylene) with pendant protonated primary amino groups (PPE-NH3+) was synthesized and characterized. The fluorescence of the conjugated polyelectrolyte PPE-NH3+ in aqueous solution changed upon addition of aldehydes. Among many commonly encountered aldehydes including formaldehyde (FA) and glutaraldehyde (GA), GA displayed the strongest quenching of the fluorescence of PPE-NH3+. The quenching efficiency reached above 85% with 1 mM of GA and the limit of detection (LOD) was 0.49 μM. The fluorescence quenching mechanism was discussed. GA, as a dialdehyde, could react with amino groups on different polymer chains simultaneously, and thus might result in more efficient chain aggregation and quenching. Finally, this sensory system was demonstrated to be very effective in detecting GA in real water samples from a water tap in our lab, a pond on the campus, Dushu lake and a river nearby a hospital. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge microplasma actuator was used for flow modification. The actuator was energized at a relatively low discharge voltage of about 1 kV. The movement of incense particles was tracked by the high-speed camera. A modulated ac voltage was applied to electrodes. It was observed using a high-speed camera how the flow velocity and direction was changed at different duty ratios of the applied voltage. The numerical simulation of the flow was carried out using the fluid model, which considers the electric potential to be the combination of the potential due the external electric field and the charge density of plasma. Based on these potentials, the body force was calculated. Furthermore, the body force was implemented in the Navier–Stokes equations and the simulated flow was obtained. The numerical results matched the obtained results in experiments. [ABSTRACT FROM PUBLISHER]

We have simulated the coupled electron and nuclear dynamics using the Ehrenfest method upon valence ionisation of modified bismethylene-adamantane (BMA) molecules where there is an electron transfer between the two π bonds. We have shown that the nuclear motion significantly affects the electron dynamics after a few fs when the electronic states involved are close in energy. We have also demonstrated how the non-stationary electronic wave packet determines the nuclear motion, more precisely the asymmetric stretching of the two π bonds, illustrating “charge-directed reactivity”. Taking into account the nuclear wave packet width results in the dephasing of electron dynamics with a half-life of 8 fs; this eventually leads to the equal delocalisation of the hole density over the two methylene groups and thus symmetric bond lengths. [ABSTRACT FROM AUTHOR]

A new class of stabilized pentacene derivatives with externally fused five-membered rings are prepared by means of a key palladium-catalyzed cyclopentannulation step. The target compounds are synthesized by chemical manipulation of a partially saturated 6,13-dibromopentacene precursor that can be fully aromatized in a final step through a DDQ-mediated dehydrogenation reaction (DDQ=2,3-dichloro-5,6-dicyano-1,4-benzoquinone). The new 1,2,8,9-tetraaryldicyclopenta[fg,qr]pentacene derivatives have narrow energy gaps of circa 1.2 eV and behave as strong electron acceptors with lowest unoccupied molecular orbital energies between −3.81 and −3.90 eV. Photodegradation studies reveal the new compounds are more photostable than 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene). [ABSTRACT FROM AUTHOR]

In this paper, several planar dielectric barrier discharge fluid-dynamics actuators have been experimentally investigated. The actuator is made by an electrode pair separated by a dielectric. It is characterized by a planar geometry, and it induces a volume force on the gas above it which modifies the fluid dynamics within the aerodynamic boundary layer. Several actuator geometries, dielectric materials, ac supply voltages, and supply frequencies have been used. Rotational and vibrational temperatures have been determined by means of spectroscopic measurements. Vibrational temperatures have been found to be one order of magnitude higher than the rotational ones, confirming the nonthermal behavior of the discharge. The translational temperature has been evaluated by thermographic observations of the dielectric surface heated by the plasma. The values of the translational temperature are in a very good agreement with those of the rotational temperature. Electric measurements have been carried out to determine the average power delivered to the discharge and to estimate the average electron number density. In the plasma induced by the discharge above the actuator, an average electron density of 4 \div 15\ 10^17\ \m^-3 has been determined. The gas speed of the induced wall jet has been measured with a Pitot tube. The average power delivered to the electrodes increases with a power law of the applied voltage (\exponent \approx 3 \div 5) and linearly with the supply frequency. The induced speed increases with the increase of the average power until a plateau is reached. The efficiencies of the different actuators have been compared by evaluating the relation between average power and induced gas speed. [ABSTRACT FROM PUBLISHER]

This paper investigates the effects of duty cycle on improvement of pressure distribution above a NLF0414 airfoil using the plasma actuators. Three dielectric barrier discharges as the plasma actuators are flush mounted on airfoil surface in different positions in order to improve pressure at post-stall angle of attacks. The experiments were performed at ReC = 7.5 \times 10^5 and the post-stall angles of attacks. The main aim of the related experiments in this paper is to better understand how duty cycles must be applied in order to have the most effective conditions for different excitation frequencies and different angles of attack. Results show that the plasma actuators in unsteady excitations are more effective in lower duty cycles on low excitation frequencies, but the lower duty cycles loss their effectiveness on higher excitation frequencies. [ABSTRACT FROM PUBLISHER]

This paper is a study of a plasma actuator in the absence of external flow by means of particle image velocimetry measurements. The properties of the electric wind produced by the actuator are investigated by spatially resolved and phase-locked measurements. The use of a particle image velocimetry apparatus is of great interest to accurately examine the spatio-temporal history of the electric wind formation. The approach consists of evaluating the time required by the induced airflow to reach a stationary state and also in describing the different states of its formation. The electric wind is generated by a single dielectric barrier discharge excited by a sine waveform of 1 kHz, having an amplitude of 20 kV. Turbulent kinetic energy, swirl strength, pure shear flow and mass flow rate are also used to describe the formation process of the airflow. [ABSTRACT FROM AUTHOR]

Chemical transformations of the norbornadiene cation radical (NRB + • ) involving intramolecular electron transfer (IET) are analysed using a two-dimensional potential surface formed by reaction coordinates along two pathways. One leads to the quadricyclane cation radical, the other to the benzene cation radical plus a methylene biradical. Two separate conical intersections between the ground state and the first excited state of (NRB +• ) are located using the Longuet–Higgins sign-inverting theorem. The implications of this finding on the photodynamics of the system are discussed. [ABSTRACT FROM AUTHOR]

The genotoxic potential of influents and effluents of two different wastewater treatment plants (WTP-A and WTPB) located in the Rouen. France, area was evaluated by the SOS chromotest without metabolic activation (on E. scherichia coli PQ37) and the Ames fluctuation test (on Salmonella typhimurium strains TA 98. 100, TA 102) with and without metabolic activation. The wastewater samples were taken during two 1-week periods in January and April 2003. The simultaneous use of the SOS chromotest and Ames fluctuation test allowed us to evaluate the efficacy of the wastewater treatment plants at removing genotoxins. Genotoxins were detected with the Ames test but not with the SOS chromotest. Out of a total of 24 influents tested (14 for WTP-A and 10 for WTP-B), almost all were genotoxic in at least one Ames test strain (71% for WTPA and 100% for WTP-B). In contrast, all of the tested effluents were nongenotoxic. This work showed that the treatment process used in the 2 wastewater treatment plants studied (activated sludge) was able to remove the genotoxins detected in their influents. Nevertheless, studies could be undertaken to determine which step of the treatment process removes genotoxins and whether WTP sludge use could be a source of genotoxic contamination for humans and the environment. [ABSTRACT FROM AUTHOR]

Extensions of traditional molecular dynamics to excited electronic states and non-Born-Oppenheimer dynamics are reviewed focusing on applicability to chemical reactions of large molecules, possibly in condensed phases. The latter imposes restrictions on both the level of accuracy of the underlying electronic structure theory and the treatment of nonadiabaticity. This review, therefore, exclusively deals with ab initio "on the fly" molecular dynamics methods. For the same reason, mainly mixed quantum-classical approaches to nonadiabatic dynamics are considered. [ABSTRACT FROM AUTHOR]

The novel, commercially available, free-flowing spherically granulated dicalcium phosphate anhydrous (SGDCPA) Fujicalin for direct tableting was compared with directly compressible dicalcium phosphate dihydrate (DCPD), the properties of which are well known. The two excipients were investigated and compared with regard to their physical and powder properties, compressibility, and compactibility. As a consequence of the spherical shape of its particles, SGDCPA shows the same good flowability and even better compactibility. In contrast to DCPD, SGDCPA shows significant uptake of moisture when exposed to relative humidities (RHs) exceeding 70%. For both excipients, the main deformation mechanism is fragmentation, with SGDCPA yielding significantly stronger tablets. [ABSTRACT FROM AUTHOR]