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This study examines the pace at which solutions to a Bresse system in combination with the Cattaneo law of heat conduction and the dispersed delay term degradation. We establish our major finding utilizing the energy approach in the Fourier space.

In this work, we deal with a one-dimensional Cauchy problem in Timoshenko system with thermal effect and damping term. The heat conduction is given by the theory of Lord-Shulman. We prove that the dissipation induced by the coupling of the Timoshenko system with the heat conduction of Lord-Shulman's theory alone is strong enough to stabilize the system, but with slow decay rate. To show our result, we transform our system into a first order system and, applying the energy method in the Fourier space, we establish some pointwise estimates of the Fourier image of the solution. Using those pointwise estimates, we prove the decay estimates of the solution and show that those decay estimates are very slow.

In this work, we consider a nonlinear transmission problem in the bounded domain with a delay term in the first equation. Under conditions on the weight of the damping and the weight of the delay, we prove general stability estimates by introducing a suitable Lyapunov functional and using the properties of convex functions.

We consider the linear field-road system, a model for fast diffusion channels in population dynamics and ecology. This system takes the form of a system of PDEs set on domains of different dimensions, with exchange boundary conditions. Despite the intricate geometry of the problem, we provide an explicit expression for its fundamental solution and for the solution to the associated Cauchy problem. The main tool is a Fourier (on the road variable)/Laplace (on time) transform. In addition, we derive estimates for the decay rate of the L ∞ norm of these solutions. [ABSTRACT FROM AUTHOR]

Twin jets are encountered in many engineering and industrial applications, such as aircraft propulsion systems and combustors. Twin jets create a flow field that is more complex than a single jet due to its interaction with the individual jets. This paper investigates the effects of spacing to diameter (S / D e ) ratio and orientation on the mixing properties of circular and elliptical twin jets at four different S / D e ratios of 1.25, 1.50, 1.75, and 2.0, respectively. The numerical simulations of twin jets are carried out with a jet Mach number of 0.8 using the Shear Stress Transport (SST) K- ω turbulence model. The results show that near the orifice exit, the twin jets are issuing into ambient conditions separately and resemble a free jet, leading to a potential core length independent of S / D e . The merging and combined point locations change linearly from the exit with an increasing S / D e ratio. The decay rate is higher for Twin Ellipse Minor than those in Twin Circle and Twin Ellipse Major, verified by a shorter converging region. In addition, near the jet exit, the spread rate is higher for Twin Ellipse Minor, which is consistent with the closer merging point location. The jet mixing is superior for twin minor elliptical configuration compared to twin circle and twin major elliptical jets at all S / D e ratios. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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.)

This paper is concerned with two dimensional Boussinesq equations involving the horizontal dissipation in the first component of the velocity and horizontal temperature diffusion. Due to the lack of so much dissipation, the stability issue becomes more challenging than that in [10]. When the spatial domain is $ \Omega = T\times R $ with $ T = [0,1] $ being a 1D periodic box, we establish the stability and build the precise large-time behavior of perturbations near the hydrostatic equilibrium. We further prove that the oscillation parts of the velocity and the temperature only share the decay rate as $ (1+t)^{-\frac12} $, which is a different phenomenon from the corresponding results in [10]. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the stability issue and large time behavior of three dimensional magnetohydrodynamic equations with velocity damping and magnetic diffusion only in the $ x_1 $-direction near a background magnetic field. Due to the lack of the magnetic diffusion in two direction, this problem becomes more challenging. The classical anisotropic Sobolev techniques to deal with MHD equations with mixed dissipation fail here. Fortunately, combining anisotropic Sobolev techniques and some interpolation methods, we can establish the asymptotic stability and explicit decay rates of the solutions to the three dimensional MHD equations mentioned above. The most difficult is to obtain the $ L^1 $-norm of $ \|\nabla_h u\|_{L^\infty} $ in time. [ABSTRACT FROM AUTHOR]

This study examines the pace at which solutions to a Bresse system in combination with the Cattaneo law of heat conduction and the dispersed delay term degradation. We establish our major finding utilizing the energy approach in the Fourier space. [ABSTRACT FROM AUTHOR]

The Cu fraction in wine associated with Cu(II)-organic acid complexes can suppress detrimental aromas attributed to hydrogen sulfide and methanethiol. However, the long-term stability of this Cu fraction (known as Cu fraction I) during bottle aging of red wine is not well understood. This study utilised Pinot Noir and Shiraz wines containing 0.43 ± 0.01 and 0.56 ± 0.02 mg/L respectively of total Cu, to which 0, 0.3 or 0.6 mg/L Cu(II) was further added immediately before bottling. The bottles were then stored at 14 °C for 1 yr. Cu fraction I concentrations were measured using two independent methods: i) stripping potentiometry, and ii) ICP-OES analysis of filtrate after diatomaceous earth depth filtration. Within the first 6 months of storage, Cu fraction I was found to decrease in all wines. Using stripping potentiometry, the first-order decay rates were found to be 0.012 ± 0.001 day-1 and 0.010 ± 0.001 day-1 for Pinot Noir and Shiraz respectively, corresponding to half-lives of 55 ± 4 and 67 ± 9 days. The decay rates for Shiraz versus Pinot Noir were similar for wines with different Cu addition rates, or when rates were determined using the different analysis techniques. Both wines had a high capacity for conversion of Cu fraction I to Cu fraction III during the 1-yr storage period, with 0.4-0.8 mg/L Cu forming Cu fraction III in the Pinot Noir, and 0.3-0.6 mg/L in the Shiraz. These conversion capacity ranges are higher than the typical Cu(II) additions made to wine during production. Overall, the results show that red wine has a large capacity for enabling the sulfide-binding of Cu-organic acid complexes during bottle aging and the conversion occurs at a relatively uniform rate with the concentration halving approximately every 2 months.

The decay rate of solutions to a Bresse system in thermoelasticity of type III with respect to the distributed delay term is the subject of this study. We demonstrate our major finding utilising the energy approach in the Fourier space. [ABSTRACT FROM AUTHOR]

In this work, we deal with a one-dimensional Cauchy problem in Timoshenko system with thermal effect and damping term. The heat conduction is given by the theory of Lord-Shulman. We prove that the dissipation induced by the coupling of the Timoshenko system with the heat conduction of Lord-Shulman's theory alone is strong enough to stabilize the system, but with slow decay rate. To show our result, we transform our system into a first order system and, applying the energy method in the Fourier space, we establish some pointwise estimates of the Fourier image of the solution. Using those pointwise estimates, we prove the decay estimates of the solution and show that those decay estimates are very slow. [ABSTRACT FROM AUTHOR]

The studies considered here are concerend with a linear thermoelastic Bresse system with delay term in the feedback. The heat conduction is also given by Cattaneo’s law. Under an appropriate assumption between the weight of the delay and the weight of the damping, we prove the well-posedness of the problem using the semigroup method. Furthermore, based on the energy method, we establish an exponential stability result depending of a condition on the constants of the system that was first considered by A. Keddi, T. Apalara, S. A. Messaoudi in 2018. [ABSTRACT FROM AUTHOR]

In the CMS detector, the branching fractions of Higgs boson to J/ψ(1S) and cc pairs have been measured equal to 1.8×10-3 and 2.89 × 10-2, respectively. Theoretically, one possible scenario for direct production J/ψ(1S) is that the Higgs boson initially decays into the pair of cc . Then, in the next step, each of the c and c directly fragments into J/ψ(1S) a meson. Based on this scenario, in this paper, the direct branching fractions of the standard model Higgs boson to J/ψ(1S) is calculated by direct fragmentation of c and c using of perturbative Quantum-Chromodynamics(pQCD) and also taking account the longitudinal and transverse polarization states J/ψ(1S). The results of our calculations for the direct branching fraction of the Higgs boson to a pair J/ψ(1S) equal to 1.562×10-3, agree well with the measured value in the CMS detector. Therefore, it can be concluded that the predominant contribution in the decay of the Higgs boson into the J/ψ(1S) meson is the direct fragment of c quark and antiquark c.

Abstract In this paper we study the von Karman plate model with long range memory. By using the assumptions on the relaxation function due to Tatar (J. Math. Phys. 52:013502, 2011), we show an arbitrary rate of decay, which is not necessarily of an exponential or polynomial decay. Our result is obtained without imposing the usual relation between the relaxation function h and its derivative.

This paper aims to examine the effects of orientation and asymmetry on the mixing characteristics of circular and elliptical twin jets produced from sharp orifices. The twin jets that emerged from two similar orifices are termed as symmetrical twin jets, and the twin jets issued from two different orifices are referred to as asymmetrical twin jets. The twin jets are separated by the spacing ratio of 2, and numerical simulations are performed at a Mach number of 0.8 and a Reynolds number based on an equivalent exit diameter of 3.46×105. RANS-based two-equation turbulence model, namely SST k-ω model was used to carry out the simulations. It was observed that the core length is not affected by the orifice orientation. However, the spread rates and velocity decay are sensitive to orifice orientation, and among the tested twin jet configurations, the circular-elliptical major asymmetrical jet experienced the highest decay and spread rates. In addition, the turbulent intensity peak values of asymmetrical twin jets decreased by 8 % compared to symmetrical twin jets. [ABSTRACT FROM AUTHOR]

In this work, we consider a nonlinear transmission problem in the bounded domain with a delay term in the first equation. Under conditions on the weight of the damping and the weight of the delay, we prove general stability estimates by introducing a suitable Lyapunov functional and using the properties of convex functions. [ABSTRACT FROM AUTHOR]

This work is concerned with a multi-dimensional viscoelastic pseudo-parabolic equation with critical Sobolev exponent. First, with some suitable conditions, we prove that the weak solution exists globally. Next, we show that the stability of the system holds for a much larger class of kernels than the ones considered in previous literature. More precisely, we consider the kernel g:[0,∞)⟶(0,∞)g:{[}0,\infty )\hspace{0.33em}\longrightarrow \hspace{0.33em}(0,\infty ) satisfying g′(t)⩽−ξ(t)G(g(t)){g}^{^{\prime} }(t)\leqslant -\xi (t)G(g(t)), where ξ\xi and GG are functions satisfying some specific properties.

Abstract We consider the global well-posedness and large time behavior of solutions for epitaxy thin film growth model in R d $\mathbb{R}^{d}$ with the dimensional d ≥ 3 $d\geq 3$ . First, using the pure energy method and a standard continuity argument, we prove that there exists a unique global strong solution under the condition that the initial data is sufficiently small. Moreover, we also establish the suitable negative Sobolev norm estimates and obtain the optimal decay rates of the higher-order spatial derivatives of the strong solution.

This paper is concerned with the stability analysis and stabilization of periodic piecewise positive systems. By constructing a time‐scheduled copositive Lyapunov function with a time segmentation approach, an equivalent stability condition, determined via linear programming, for periodic piecewise positive systems is established. Based on the asymptotic stability condition, the spectral radius characterization of the state transition matrix is proposed. The relation between the spectral radius of the state transition matrix and the convergent rate of the system is also revealed. An iterative algorithm is developed to stabilize the system by decreasing the spectral radius of the state transition matrix. Finally, numerical examples are given to illustrate the results. [ABSTRACT FROM AUTHOR]

We revisit rescaling methods for nonlinear elliptic and parabolic problems and show that, by suitable modifications, they may be used for nonlinearities that are not scale-invariant even asymptotically and whose behavior can be quite far from power like.In this enlarged framework, by adapting the doubling-rescaling method from [37, 38], we show that the equivalence found there between universal estimates and Liouville theorems remains valid. In the parabolic case we also prove a Liouville type theorem for a rather large class of non scale-invariant nonlinearities. This leads to a number of new results for non scale-invariant elliptic and parabolic problems, concerning space or space-time singularity estimates, initial and final blow-up rates, universal and a priori bounds for global solutions, and decay rates in space and/or time.We illustrate our approach by a number of examples, which in turn give indication about the optimality of the estimates and of the assumptions. [ABSTRACT FROM AUTHOR]

In this paper we study the von Karman plate model with long range memory. By using the assumptions on the relaxation function due to Tatar (J. Math. Phys. 52:013502, 2011), we show an arbitrary rate of decay, which is not necessarily of an exponential or polynomial decay. Our result is obtained without imposing the usual relation between the relaxation function h and its derivative. [ABSTRACT FROM AUTHOR]

In order to study the effects of different storage temperatures and preservatives on the preservation effects of Qiuyang pear fruits, the effects of 0.5 μL/L 1 -methylcyclopropene (1 -MCP) fumigation for 12 h and ethylene adsorbent treatments on the storage qualities of Qiuyang pears were investigated under different storage temperatures (-1 °C and 0 °C). The results showed that after 120 days of storage, the decay rates of fruits stored at 0°C was lower than that stored at -1°C under the same treatment conditions. At 270 days, the decay rates of fruits stored at 0 °C and -1°C in the two preservatives treatment groups were lower than those in CK group. The fruits peels brightness of CK group and ethylene sorbent treatment group at 0°C was higher than that stored at -1 °C. After 240 days of storage, the fruits hardness of 1-MCP treatment group was remarkably higher than that of other treatments groups (P<0.05), and the fruits hardness of 1-MCP treatment group stored at 0°C was significantly higher than that stored at -1°C at 270 days (P<0.05). The titratable acid contents of fruits in the two preservatives treatment groups were higher than that in CK group at 270 days of storage. The soluble solids contents of fruits in each group presented no significant changes during storage. In conclusion, Qiuyang pears presented low decay rates and well maintained peels brightness when stored at 0°C. The two preservatives treatments could both reduce the decay rates and delay the decline of titratable acid contents of Qiuyang pears, and the 1-MCP treatment showed better effects that could effectively maintain peel brightness and fruit firmness. [ABSTRACT FROM AUTHOR]

In this paper, we study the full parabolic attraction–repulsion Keller–Segel model with a fractional diffusion in ℝn$$ {\mathbb{R}}^n $$ for n=2$$ n=2 $$ or 3. We are more interested in the question that whether the solutions exist globally or blow up in finite time, which was studied in the classical attraction‐repulsion Keller‐Segel model by Jin and Wang (J. Differential Equations, 2016) through constructing a suitable energy functional. However, for the fractional attraction–repulsion Keller–Segel model, it is challenging to find a similar energy functional to study the existence of the solutions. In the present paper, under the condition of ξγ=χα$$ \xi \gamma =\chi \alpha $$, we introduce the Lp$$ {L}_p $$‐ Lq$$ {L}_q $$ estimates of the fractional derivative modulus of the solution to carry out the first step of the problem. Armed with a priori estimate, it is sufficient for us to obtain the global existence of the solutions by the Moser–Alikakos iterative method and finally arrive at the decay estimates of the solutions. [ABSTRACT FROM AUTHOR]

Hawkes processes with exponential kernels are a ubiquitous tool for modeling and predicting event times. However, estimating their decay parameter is challenging, and there is a remarkable variability among decay parameter estimates. Moreover, this variability increases substantially in cases of a small number of realizations of the process or due to sudden changes to a system under study, for example, in the presence of exogenous shocks. In this work, we demonstrate that these estimation difficulties relate to the noisy, non-convex shape of the Hawkes process' log-likelihood as a function of the decay. To address uncertainty in the estimates, we propose to use a Bayesian approach to learn more about likely decay values. We show that our approach alleviates the decay estimation problem across a range of experiments with synthetic and real-world data. With our work, we support researchers and practitioners in their applications of Hawkes processes in general and in their interpretation of Hawkes process parameters in particular. [ABSTRACT FROM AUTHOR]

We give an overview of some recent results on operator-valued (L p , L q) Fourier multipliers and stability theory for evolution equations. The aim is to provide a relatively nontechnical introduction to the underlying ideas, emphasizing the connection between the two areas. We also indicate how operator-valued (L p , L q) Fourier multipliers can be applied to functional calculus theory. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a Bresse-type system of thermoelasticity of type III in the presence of a distributed delay. We prove the well-posedness of the problem. Further- more, an exponential stability result will be shown without the usual assumption on the wave speeds. To achieve our goals, we make use of the semigroup method and the energy method. [ABSTRACT FROM AUTHOR]

Winged beans accumulate abundant field heat following harvest, and their shelf life is shortened if precooling is not performed promptly. In the present study, top-suction forced-air precooling (FC) was employed to rapidly remove field heat from pods, and its effects on winged bean pod storage quality and shelf life were assessed. After postharvest FC to remove field heat from winged bean pods, the mean 1/2 precooling time was 5.8 min and 7/8 precooling time was 14.7 min, which was 9.6 times and 11.7 times faster than room cooling (RC), respectively. Moreover, after FC was applied to remove field heat, the weight loss rate at 7/8 precooling time was 0.92%, significantly lower than that after RC was applied (1.98%). FC could delay decay, and the decay rate was only 18% on day 14 storage, which was lower than 52% of RC. During 12 °C and 85% relative humidity (RH) storage, the shelf life of winged bean pods in the FC group was 14.8 days, which was significantly longer than that of the pods in the RC group (10.6 days). In conclusion, FC is an effective precooling method to rapidly remove field heat postharvest and maintain the storage quality of winged beans. [ABSTRACT FROM AUTHOR]

We consider equations describing the thermoelastic behavior of plates modeled in the Green-Lindsay sense. This is done with two different type of couplings of the fourth-order plate Kirchhoff-type plate equation to a second-order heat equation of Cattaneo type, once of second, and once of first order. We investigate both systems for bounded domains and for the Cauchy problem, asking for exponential stability in bounded domains resp. polynomial decay rates for the Cauchy problem. It turns out that one system is exponentially stable, while the other is not, and that, in correspondence, one does not have and the other one has regularity loss in the Cauchy problem. This provides a new interesting example where the different couplings lead to qualitatively different behavior, as known before for classical thermoelastic plates, for Timoshenko systems, for porous elasticity or for plates with two temperatures, with Fourier resp. Cattaneo heat conduction. The optimality of the decay rates obtained is also proved. [ABSTRACT FROM AUTHOR]

Thinning is widely employed in forest management to improve productivity, protect forest biodiversity and maintain ecosystem functions. Here a thinning experiment with four treatments (unthinned, CK; 30% tree removal from below, MB; 50% tree removal by interlaced thinning, HI; and 50% tree removal from below, HB) was set up in the poplar plantation, while a followed decomposition experiment with four litter types was conducted under the poplar plantations of undergoing four thinning treatments using the litterbag technique. Thinning affected the microclimate, but only the heavy thinning (HI and HB) significantly enhanced photosynthetic photon flux density (PPFD) and soil moisture in the plantations during the growing season. Thinning promoted understory vegetation biomass and vegetation diversity via modifying the microclimate parameters. Pearson correlation analysis showed that PPFD and understory herbaceous biomass were significantly correlated to Shannon-Weiner diversity index. Both thinning intensity and litter type significantly affected the litter remaining mass over times. Overall, increasing thinning intensity and litter complexity enhanced decay rate, while reduced half live (t0.5) and t0.95 values. Correlation analysis showed that air relative humidity, soil temperature, air temperature and soil moisture significantly influenced the litter mass loss rates. Nonadditive (synergistic) effects were observed when different litters were mixed, but the nonadditive effect was most pronounced when more herbaceous species litter were mixed with poplar leaves and 50% thinning intensity was applied. Dynamics of nutrient release from different litter types were similar to those on the litter mass lose, depending on the litter quality and microclimatic conditions. Our results suggest that a thinning operation with 50% tree removal from below (HB) would maintain the structural and functional features of the poplar plantations at the similar sites. [ABSTRACT FROM AUTHOR]

One of the dominant modes of decay of the standard model Higgs boson is its decay into b pair. Subsequently, either b or can fragment directly into the upsilon meson. In this paper, the direct branching fractions of the standard model Higgs boson to the upsilon meson are calculated via direct fragmentation b and quarks. The results obtained from our calculations show that, the decay ratio of the Higgs boson to the upsilon pair is equal to , which is a very good agreement with the value reported by CMS Collaboration which is equal to . In addition, the direct decay branching fraction of the Higgs boson to the pair upsilon with longitudinal polarization from our calculations, compare to its decay to the unpolarization upsilon pair, it shows a 13% reduction, which is comparable to the 22% decrease is reported by the CMS Collaboration. Therefore, it can be concluded that the dominant contribution in the decay of the Higgs boson to the upsilon, is the direct fragmentation of the quark b and antiquark .

Consider the non-stationary Navier-Stokes equation in the upper half space of R n. We prove the decay estimates of the strong solution and its derivatives in the setting of Besov and Triebel–Lizorkin spaces. This is the first time that the decay estimates of solutions to the non-stationary Navier-Stokes equations on Besov and Triebel-Lizorkin spaces are established. Our results not only extend the known results from Hardy spaces to Besov and Triebel-Lizorkin spaces but also imply new estimates on Sobolev spaces and give better decay estimates on Hardy spaces. [ABSTRACT FROM AUTHOR]

In this paper, we consider the following Kirchhoff-type equation: - a + b ∫ R N | ∇ u | 2 d x Δ u + λ V (x) u + μ ϕ | u | p - 2 u = | u | q - 2 u , in R N , (- Δ) α 2 ϕ = | u | p , in R N , where a , b > 0 , 0 < α < N , N ≥ 3 , 2 ≤ p < N + α N - 2 , 2 < q < min { 4 , 2 ∗ } , 2 ∗ = 2 N / (N - 2) and λ , μ > 0 are parameters. Using the truncation technique and the parameter-dependent compactness lemma, we prove the existence of positive solutions for the above problem when b , μ are sufficiently small, and λ is large enough. Furthermore, the decay rate and the asymptotic behavior of the positive solutions are also explored. [ABSTRACT FROM AUTHOR]

In this work, we investigate the global well-posedness and asymptotic behavior of a mathematical model of ultrasound-induced heating based on a coupled system of Westervelt's nonlinear acoustic wave equation and Pennes bioheat equation. To this end, under Dirichlet–Dirichlet boundary conditions, we prove global existence for sufficiently small and smooth solutions of the nonlinear model using an energy method. In addition, we show that the energy norm of the resulting pressure and temperature decays to the steady state exponentially fast. [ABSTRACT FROM AUTHOR]

Stability estimates are obtained for delayed linear periodic discrete-time systems. Bounds on the decay of the solution are derived via a suitable Lyapunov–Krasovskii-type functional and the solvability of some periodic discrete-time Lyapunov equations. [ABSTRACT FROM AUTHOR]

We consider the global well-posedness and large time behavior of solutions for epitaxy thin film growth model in R d with the dimensional d ≥ 3 . First, using the pure energy method and a standard continuity argument, we prove that there exists a unique global strong solution under the condition that the initial data is sufficiently small. Moreover, we also establish the suitable negative Sobolev norm estimates and obtain the optimal decay rates of the higher-order spatial derivatives of the strong solution. [ABSTRACT FROM AUTHOR]

A method for the determination of neotame in tobacco sweet tipping paper was established by high performance liquid chromatography with diode array detector (HPLC-DAD). Based on this method, the effects of different storage environments ( low temperature and normal humidity, normal temperature and normal humidity, normal temperature and dry) on the content of neotame were analyzed, and the decay behavior of different brands of tipping paper in various environments was fitted by reaction kinetics model. The results showed that the established analytical method exhibited good linearity in the concentration range of 1. 00 ~ 800. 00 µg/mL. The method had high recovery rate and precision, which could be applied for the detection and analysis of neotame in sweet tipping paper. Under different environments, the decay rate of neotame in all brands of tipping paper increased with the prolonged storage time. The low temperature and normal humidity environment was more conducive to the stable storage of sweet tipping paper, while the normal temperature and dry environment could promote the decay of neota-me. The decay behavior of neotame in different brand tipping papers conformed to different reaction kinetic models. The decay kinetic process of different tipping paper was affected by the environment, which may be related to the microstructure of the tipping paper or the interaction between neotame and the carrier. [ABSTRACT FROM AUTHOR]

In the US Virgin Islands (USVI), roof-harvested rainwater is a primary source of domestic water and is collected in large cisterns and pumped throughout the household premise plumbing system. However, previous literature suggests that roof-harvest rainwater is prone to microbial contamination. A common local water treatment practice is direct batch chlorination of this water (>20,000 L). Provided this local habit, Love City Strong (LCS) established a pilot program to evaluate if direct batch chlorination of water in cisterns was effective and economically feasible to produce consistently adequate levels of free chlorine residual (FCR) at the kitchen tap. A trained field team utilized nine actively used cisterns to conduct a series of chlorine dosing trials where the cistern water was dosed, and, subsequently, monitored every three days. Water quality data were collected throughout, and new trials were initiated once FCR values reached ≤0.05 ppm. Evaluation criteria included: (1) the variability in duration between a dosing event and an FCR measurement <0.2 ppm , (2) the variability of achieving a target FCR level of 1.5 ppm, (3) the variability in the first-order chlorine decay rate, and (4) the costs of the method. Results suggested that the variability in duration, achieving a target FCR, and the decay rate were prohibitively high for consistent use of the method. The duration ranged from 3 to 33 days (mean: 11.5; n=34). This large range may have been influenced by the low probability (18%) of achieving an initial target FCR between 1.25 and 1.75 ppm. In addition, the chlorine decay rate ranged from 0.095 to 0.482 d−1 (mean: 0.251 d−1), resulting in an estimated duration ranging between 5 and 22 days. Finally, the first-year cost was $622 ($244 excluding person-time costs), while annual costs thereafter were $567 ($204 excluding person-time costs). Given these data, we do not recommend the use of direct batch chlorination for treating cistern water for microbial contamination in USVI households. [ABSTRACT FROM AUTHOR]

In this paper, the decay of the meson into two vector mesons and is investigated.The first observation of the decay was reported in 2017 by LHCb collaboration, they have obtained the value of B () = (5. 01 ± 053 ± 0.27 ± 0.06)×10-4. In this study, the Feynman diagram of decay is drawn based on the standard model. In particular this diagram shows that the decay consists of tree-exchange internal w-emission graph and penguin- suppressed graph. The coefficients of a2, a3, a5 and a7 are calculated in the NLO scale. The branching ratio is calculated using the QCD factorization method, numerical values in the NLO (at mb scale) scheme is 5.33×10-4, for which are in good agreement with the experimental results. The more calculations accuracy increases, the b quark mass scales come down corresponding to that. The best answer close to the experimental value is in NLO scheme at mb scale of QCDF approach.‎

Deadwood decomposition modulates habitat structure and enhances resource availability within forest ecosystems. Deadwood decomposition is influenced by a combination of abiotic and biotic factors, wherein climatic variables, tree species, and wood characteristics play fundamental roles. However, the scarcity of studies conducted in dry and semiarid regions restricts our understanding of deadwood decomposition dynamics. Here, we studied the decomposition of logs in four plots across an elevation gradient spanning approximately 1000 m (from 1477 to 2317 m a.s.l.). The site was a burnt reforestation of different pine species in a Mediterranean mountain (Sierra Nevada, SE Spain). Logs of a range of diameters were cut to a similar length (75 cm), and their density loss was monitored over 15 years. We fitted three different types of functions (linear, negative exponential and negative sigmoidal) to evaluate the temporal trajectory of decomposition across the elevation gradient. Average wood density loss through the 15-year period ranged from 30.4 % to 63.3 % depending on the elevation plot, and it was highest at an intermediate elevation. The negative sigmoidal equation showed the best fit, but all functions rendered similar half-life values, which ranged between 12.8 and 29.4 years depending on the elevation plot. Contrary to most studies, larger-diameter logs experienced a quicker decomposition process, which could be linked to increased moisture retention and greater activity of large invertebrates in the larger-diameter logs. The variations observed across the elevation gradient are consistent with expectations on how the interaction between precipitation and temperature influences decomposition rates. The observed decomposition patterns in these mountain forests indicate a relatively rapid process, and underline the vital contribution of deadwood biological legacies to the preservation of soil fertility in the Mediterranean region. • We studied wood decomposition for 15 y in a Mediterranean mountain at 1477 – 2317 m elevation. • Trunks lost 30.4 % – 63.3 % of density, peaking at intermediate elevation. • A negative sigmoidal curve explained the process better than a linear or negative exponential. • Modelled half-life of wood ranged from 12.8 to 29.4 y across elevations. • Thicker logs decomposed faster, challenging findings from other regions. [ABSTRACT FROM AUTHOR]

This article discusses the extent of the spread of contamination in water distribution networks which may enter through a pipe leak, and the decay rate of chlorine for a specified design duration. A comprehensive water quality analysis is performed using EPANet 2.2 for the spread of contamination and chlorine decay. The results show that a contaminant entering at the highest point of the network would pollute the whole network whereas the effect of such a contaminant would be limited if it enters at the lowest location. Also, the initial chlorine concentration is found to be more for such critical nodes which are higher in elevation, although the decay rate remains the same. The research proves to be beneficial for the management of water distribution through pipe networks against contaminants for maintaining public health.

The long time behavior of a class of degenerate parabolic equations in a bounded domain will be considered in the sense that the nonnegative diffusion coefficient a(x)is allowed to vanish in a set of positive measure in the interior of the domain. We prove decay rates for a class of semilinear reaction diffusion equations and a nonlinear equation governed by the p-Laplacian, for p>2.

Temperature plays an important role in vegetable and fruit storage. In this study, the Cucumis melo var. reticulatus Chuanmicuiyu planted in Chengdu plain were stored at different temperatures by comparing the quality of muskmelon during storage. The results showed that cold storage (5, 8, 12 °C) significantly reduced breathing rate, decay rate, and decay index of muskmelon, delayed the increase of malondialdehyde content and the loss of hardness, and maintained a higher brightness (L* value). Besides, there was no serious cold injury of the muskmelon observed during storage. Among the three low temperatures, 5 °C was the best one, which demonstrated storing at this temperature could effectively extends the storage time of Cucumis melo var. reticulatus, and maintained its good appearance even after 28 days storage. [ABSTRACT FROM AUTHOR]

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Samples of α-glycine (α-GLY; 230–350 nm) were irradiated in laboratory as a function of electron beam energies (0.25, 0.50, and 1.00 keV) at room temperature (293–295 K). The evolution of α-glycine irradiation process was monitored in real time by infrared spectroscopy (Fourier transform infrared - FTIR), through specific spectral bands: 2610, 2124, 1410, and 1333 cm−1. A phenomenological model is proposed to describe the column density decay when thick organic samples are processed by ionizing beams. The α-glycine radiolysis has exhibited transient and stationary modes in such thickness films. The first stage is mainly described by one exponential decay, whereas the latter foremost decays linearly; compaction processes have been neglected; glycine dissociation and sputtering processes are assumed to be responsible for the damage caused by the electron beam impact through the solid film. The second (stationary) stage is due to equilibrium between a partially shielded bulk radiolysis and sputtering of protective layers. The decay rates are measured for the transient and stationary modes and allow determining the processing velocity of the samples as a function of the electron beam energy. Finally, the model is applied to space weathering to find out the typical sputtering rate of organic compounds on the surface of astrophysical analogs with no protection layers attacked by solar wind (SW) electrons at ≈1 AU. Although the velocity of processing materials in SW has natural competing effects, such as regolith overturn by impacts of micro- and macrometeorites and downslope motion of material that is unstable due to changes in the geopotential of the airless bodies (e.g., asteroid 101955 Bennu), these competing processes are not included in the simulations presented here. [ABSTRACT FROM AUTHOR]

Stability analysis of switched DC-DC converters is necessary because instability enhances current ripple and causes converter operation at unwanted voltage/current level. In the present study, stability analysis of switched converters using Lie Algebra has been performed considering the switched linear model of DC-DC converters. The switched linear system is asymptotically stable if the Lie bracket formed by the state matrices of the system is commutative. The Lie Algebra is generated and its derived series is also computed. The Lie Algebra is found to be solvable, consequently the switched system is exponentially stable under arbitrary switching. The effect of duty cycle variation and load resistance of DC-DC converters, working in continuous conduction mode (CCM) on the decay constant and decay coefficient, has also been studied. The decay coefficient and decay rate of this exponentially stable system are observed to increase with an increase in the duty cycle for a specific load resistance. [ABSTRACT FROM AUTHOR]