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Performance Test Of Zn-Astaxanthin Complex-Sensitized Solar Cell: Effect Of Light Intensity On Open-Circuit Voltage And Short-Circuit Current Values, Septiani Septiani, Winda Rahmalia, Thamrin Usman Apr 2024

Performance Test Of Zn-Astaxanthin Complex-Sensitized Solar Cell: Effect Of Light Intensity On Open-Circuit Voltage And Short-Circuit Current Values, Septiani Septiani, Winda Rahmalia, Thamrin Usman

Turkish Journal of Chemistry

The sensitizer is one of the most essential dye-sensitized solar cell (DSSC) components. In the present research, a Zn-astaxanthin complex was investigated as a sensitizer, compared to pure astaxanthin. The complex with a 1:1 mole ratio between astaxanthin and Zn2+ was synthesized in a reflux reactor at 37–60 °C. The product was analyzed using Proton Nuclear Resonance (1H-NMR), which indicates the presence of chelate formation between Zn2+ with two atoms of oxygen on the terminal cyclohexane ring of astaxanthin. The interaction of sensitizers (astaxanthin and Zn-astaxanthin) on the photoelectrode surface in this study was analyzed using a Fourier Transform Infra-Red …


Analisa Kestabilan Bebas Kecanduan Pada Penyebaran Penggunaan Media Sosial Berdasarkan Model Searqs, Ratna Widayati, Intrada Reviladi Dec 2023

Analisa Kestabilan Bebas Kecanduan Pada Penyebaran Penggunaan Media Sosial Berdasarkan Model Searqs, Ratna Widayati, Intrada Reviladi

PYTHAGORAS : Jurnal Matematika dan Pendidikan Matematika

Penelitian ini membahas mengenai model penyebaran penggunaan media sosial dan analisa kestabilan di sekitar titik ekuilibrium serta simulasi numeriknya dengan mengasumsikan populasi individu dibagi menjadi 5 kelas yaitu individu yang rentan terhadap kecanduan media sosial, individu yang menggunakan media sosial tetapi belum timbul kecanduan, individu kecanduan/adiktif media sosial, individu sembuh dari kecanduan media dan individu yang berhenti menggunakan media sosial. Model matematika yang digunakan adalah SEARQS dengan asumsi tidak ada kematian karena kecanduan media sosial. Selain itu, individu yang telah berhenti dari kecanduan media sosial, dapat kembali menjadi individu rentan. Permasalahan yang timbul dari penyebaran penggunaan media sosial yang berlebihan …


A Comprehensive Review Of Geometrical Thermodynamics: From Fluctuations To Black Holes, S. Mahmoudi, Kh. Jafarzade, Seyed Hossein Hendi Oct 2023

A Comprehensive Review Of Geometrical Thermodynamics: From Fluctuations To Black Holes, S. Mahmoudi, Kh. Jafarzade, Seyed Hossein Hendi

Turkish Journal of Physics

This paper presents a comprehensive review of geometrical thermodynamics, which employs geometric concepts to study the thermodynamic properties of physical systems. The review covers key topics such as thermodynamic fluctuation theory, proposed thermodynamic metrics in various coordinate systems, and thermodynamic curvature.Additionally, the paper discusses the geometrical approach to black hole thermodynamics and provides an overview of recent research in this field.


The Application Of Brzdek's Fixed Point Theorem In The Stability Problem Of The Drygas Functional Equation, Mehdi Dehghanian, Yamin Sayyari Sep 2023

The Application Of Brzdek's Fixed Point Theorem In The Stability Problem Of The Drygas Functional Equation, Mehdi Dehghanian, Yamin Sayyari

Turkish Journal of Mathematics

Using the Brzdek fixed point theorem, we establish the Hyers?Ulam stability problem of Drygas functional equations \begin{equation} \delta(x+y-z)+\delta(x-y)+\delta(-y-z)+\delta(y)=\delta(x-y-z)+\delta(y-z)+\delta(x+y)+\delta(-y)\nonumber \end{equation} for all $x,y,z\in A$.


(R1954) Fractional Order On Modeling The Transmission Of Devastative Covid-19 Infection: Efficacy Of Vaccination, Ashutosh Rajput, Tanvi ., Rajiv Aggarwal, Arpana Sharma, Shiv Kumar Sahdev, Manoj Kumar, Jaimala . Jun 2023

(R1954) Fractional Order On Modeling The Transmission Of Devastative Covid-19 Infection: Efficacy Of Vaccination, Ashutosh Rajput, Tanvi ., Rajiv Aggarwal, Arpana Sharma, Shiv Kumar Sahdev, Manoj Kumar, Jaimala .

Applications and Applied Mathematics: An International Journal (AAM)

The second wave of COVID-19 is an unprecedented condition in India and began in mid February 2021. Individuals who were already suffering from other comorbidities were found with lung infection, and hence, the number of disease induced deaths were rising faster during the second wave in relation to the first wave. This paper has proposed a mathematical model with fractional order derivatives by correlating the model based number of infectives with the real number of infectives in India. For the system of fractional differential equations, a disease-free state has been computed and proved to be locally asymptotically stable with certain …


(R2032) Modeling The Effect Of Sanitation Effort On The Spread Of Carrier-Dependent Infectious Diseases Due To Environmental Degradation, Ram Naresh, Sandhya Rani Verma, J. B. Shukla, Manju Agarwal Jun 2023

(R2032) Modeling The Effect Of Sanitation Effort On The Spread Of Carrier-Dependent Infectious Diseases Due To Environmental Degradation, Ram Naresh, Sandhya Rani Verma, J. B. Shukla, Manju Agarwal

Applications and Applied Mathematics: An International Journal (AAM)

In this present study, an SIS model is proposed and analyzed to study the effect of sanitation effort in controlling the spread of carrier-dependent infectious disease in a human habitat due to environmental degradation. The dynamics of the model consist of six dependent variables, the susceptible population density, infective population density, carrier population density, cumulative density of environmental degradation and the density of sanitation effort applied on carrier population and degraded environment. In the modeling process, the carrier population density and sanitation effort are modeled logistically and the degradation of the environment is assumed to be directly proportional to the …


Qualitative Study Of A Second Order Difference Equation, Messaoud Berkal, Juan Francisco Navarro Jan 2023

Qualitative Study Of A Second Order Difference Equation, Messaoud Berkal, Juan Francisco Navarro

Turkish Journal of Mathematics

In this paper, we study a second order rational difference equation. We analyze the stability of the unique positive equilibrium of the equation and prove the existence of a Neimark-Sacker bifurcation, validating our theoretical analysis via a numerical exploration of the system.


(R2020) Dynamical Study And Optimal Harvesting Of A Two-Species Amensalism Model Incorporating Nonlinear Harvesting, Manoj Kumar Singh, Poonam . Dec 2022

(R2020) Dynamical Study And Optimal Harvesting Of A Two-Species Amensalism Model Incorporating Nonlinear Harvesting, Manoj Kumar Singh, Poonam .

Applications and Applied Mathematics: An International Journal (AAM)

This study proposes a two-species amensalism model with a cover to protect the first species from the second species, with the assumption that the growth of the second species is governed by nonlinear harvesting. Analytical and numerical analyses have both been done on this suggested ecological model. Boundedness and positivity of the solutions of the model are examined. The existence of feasible equilibrium points and their local stability have been discussed. In addition, the parametric conditions under which the proposed system is globally stable have been determined. It has also been shown, using the Sotomayor theorem, that under certain parametric …


(Si10-056) Fear Effect In A Three Species Prey-Predator Food-Web System With Harvesting, R. P. Gupta, Dinesh K. Yadav Oct 2022

(Si10-056) Fear Effect In A Three Species Prey-Predator Food-Web System With Harvesting, R. P. Gupta, Dinesh K. Yadav

Applications and Applied Mathematics: An International Journal (AAM)

Some recent studies and field experiments show that predators affect their prey not only by direct capture; they also induce fear in prey species, which reduces their reproduction rate. Considering this fact, we propose a mathematical model to study the fear effect of a middle predator on its prey in a three-species food web system with harvesting. The ecological feasibility of solutions to the proposed system is guaranteed in terms of positivity and boundedness. The local stability of stationary points in the proposed system is derived. Multiple co-existing stationary points for the proposed system are observed, which makes the problem …


Investigating The Causes Of Stope Instability At Golden Valley Mine, Ashley Ruvimbo Sabao, Prosper Munemo, Peter Kolapo Aug 2022

Investigating The Causes Of Stope Instability At Golden Valley Mine, Ashley Ruvimbo Sabao, Prosper Munemo, Peter Kolapo

Journal of Sustainable Mining

The study is based on mining operations that are concentrated in a ground exposed to flooding with varying stope dimensions. Stope stability was assessed in the four stopes, which resembled the mine’s different ground conditions using the stability graph complemented by the equivalent linear over break slough (ELOS) stability approach. The stability graph showed that the stopes in rock masses exposed to flooding fell in the potentially unstable and caving zones whereas the ones that were not affected by flooding fell in the stable zones. The ELOS approach showed that mining the previously flooded rock masses resulted in high over-breaks …


Perovskite Solar Cells, Liqiu Zheng Dr., Tyler Hurst, Zhongrui Li Aug 2022

Perovskite Solar Cells, Liqiu Zheng Dr., Tyler Hurst, Zhongrui Li

Georgia Journal of Science

The semiconductor perovskite CsPbBr2I was doped with Mn2+ to modulate its optical and photovoltaic performance. The Mn2+-doped CsPb0.9Mn0.1Br2I exhibited improved crystalline quality. Ultraviolet and visible spectroscopy of Mn2+-doped CsPb0.9Mn0.1Br2I revealed enhanced absorption capacity. Although the efficiency was not as good as desired, the enhanced light absorption of CsPb0.9Mn0.1Br2I still boosted the photovoltaic performance when it was utilized as a light absorber in perovskite solar cells, along with a low-cost carbon electrode. Compared with its counterpart …


Optimization Design Of High Loess Slope Based On Combination Of Wide And Narrow Platform:A Case Study Of An Industrial Square In Zichang City, Nan Ning, Li Peng, Su Shengrui, Dong Fu, Ma Chi Jun 2022

Optimization Design Of High Loess Slope Based On Combination Of Wide And Narrow Platform:A Case Study Of An Industrial Square In Zichang City, Nan Ning, Li Peng, Su Shengrui, Dong Fu, Ma Chi

Coal Geology & Exploration

The construction of a coal mine industrial square in a mountainous area or hilly area will face the problem of high slopes. The unreasonable high slope design causes serious waste of land resources, environmental damage and an increase in investment, and also brings huge potential safety risks to the infrastructure. Based on this, with a high slope in a coal mine industrial square in Zichang City of Shaanxi Province as an example, the field investigation, theoretical analysis and numerical simulation were used to investigate the influence of different numbers, positions and widths of wide platforms on the stress, strain field …


(R1507) Mathematical Modeling And Analysis Of Seqiahr Model: Impact Of Quarantine And Isolation On Covid-19, Manoj Kumar Singh, . Anjali Jun 2022

(R1507) Mathematical Modeling And Analysis Of Seqiahr Model: Impact Of Quarantine And Isolation On Covid-19, Manoj Kumar Singh, . Anjali

Applications and Applied Mathematics: An International Journal (AAM)

At the moment in time, an outbreak of COVID-19 is transmitting on from human to human. Different parts have different quality of life (e.g., India compared to Russia), which implies the impact varies in each part of the world. Although clinical vaccines are available to cure, the question is how to minimize the spread without considering the vaccine. In this paper, via a mathematical model, the transmission dynamics of novel coronavirus with quarantine and isolation facilities have been proposed. The examination of the proposed model is set in motion with the boundedness and positivity of the solution, sole disease-free equilibrium, …


(R1882) Effects Of Viscosity, Oblateness, And Finite Straight Segment On The Stability Of The Equilibrium Points In The Rr3bp, Bhavneet Kaur, Sumit Kumar, Rajiv Aggarwal Jun 2022

(R1882) Effects Of Viscosity, Oblateness, And Finite Straight Segment On The Stability Of The Equilibrium Points In The Rr3bp, Bhavneet Kaur, Sumit Kumar, Rajiv Aggarwal

Applications and Applied Mathematics: An International Journal (AAM)

Associating the influences of viscosity and oblateness in the finite straight segment model of the Robe’s problem, the linear stability of the collinear and non-collinear equilibrium points for a small solid sphere m3 of density \rho3 are analyzed. This small solid sphere is moving inside the first primary m1 whose hydrostatic equilibrium figure is an oblate spheroid and it consists of an incompressible homogeneous fluid of density \rho1. The second primary m2 is a finite straight segment of length 2l. The existence of the equilibrium points is discussed after deriving the pertinent …


Electrochemical Degradation Of Oxytetracycline Catalyzed By Fe3O4 Magnetic Nanoparticles, Fang Ying, Shan-Shan Xu, Yan-Bing Xu, Miao-Miao Liang, Jian-Feng Li Apr 2022

Electrochemical Degradation Of Oxytetracycline Catalyzed By Fe3O4 Magnetic Nanoparticles, Fang Ying, Shan-Shan Xu, Yan-Bing Xu, Miao-Miao Liang, Jian-Feng Li

Journal of Electrochemistry

The purpose of this study is to optimize the electrochemical degradation of oxytetracycline (OTC) in water using a low cost and simple preparation method. In this paper, the Fe3O4 magnetic nanoparticles were used as catalysts to activate the electrochemical oxidation system of peroxydisulfates (PDS) which acted as electrolytes to provide active free radicals in order to improve the degradation of OTC under the condition of applying current. As one of the tetracycline antibiotics (TCs), OTC is one of the most used antibiotics in the world, therefore, it is necessary to study the effective degradation of OTC. By …


Improved Ant Colony Optimization Algorithm For Jamming Resource Allocation, Qingyun Wang, Dezhong Jiao, Shi Shuo, Genyan Peng, Junhua Sun, Yuxin Duan Jan 2022

Improved Ant Colony Optimization Algorithm For Jamming Resource Allocation, Qingyun Wang, Dezhong Jiao, Shi Shuo, Genyan Peng, Junhua Sun, Yuxin Duan

Journal of System Simulation

Abstract: Ant Colony Optimization (ACO) is a new intelligence optimization algorithm. When applied to jamming resource allocation, the velocity of convergence in optimization process is slow and the probability of obtaining the global optimal solution is low. In order to raise the efficiency of jamming resource allocation and the probability of getting global optimal solution, the attenuation factor is improved to a variable that changes according to the exponential function in optimization process. The attenuation factor is taken as a relatively small value in the initial search phase, and increases monotonically and exponentially as the number of iterations increases. Simulation …


Some Convergence, Stability, And Data Dependence Results For $K^{\Ast }$ Iterative Method Of Quasi-Strictly Contractive Mappings, Ruken Çeli̇k, Neci̇p Şi̇mşek Jan 2022

Some Convergence, Stability, And Data Dependence Results For $K^{\Ast }$ Iterative Method Of Quasi-Strictly Contractive Mappings, Ruken Çeli̇k, Neci̇p Şi̇mşek

Turkish Journal of Mathematics

In a recent paper, Yu et al. obtained convergence and stability results of the $K^{\ast }$ iterative method for quasi-strictly contractive mappings [An iteration process for a general class of contractive-like operators: Convergence, stability and polynomiography. AIMS Mathematics 2021; 6 (7): 6699-6714.]. To guarantee these convergence and stability results, the authors imposed some strong conditions on parametric control sequences which are used in the $K^{\ast }$ iterative method. The aim of the presented work is twofold: (a) to recapture the aforementioned results without any restrictions imposed on the mentioned parametric control sequences (b) to complete the work of Yu et …


Difference Schemes Of High Accuracy For Equation Of Spin Waves In Magnets, Mirsaid Aripov, Dauletbay Utebaev, Zhusipbay Nurullaev Dec 2021

Difference Schemes Of High Accuracy For Equation Of Spin Waves In Magnets, Mirsaid Aripov, Dauletbay Utebaev, Zhusipbay Nurullaev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

Three-parameter difference schemes of the finite element method with a high order of accuracy are considered in the article for a mathematical model of spin waves in magnets (Sobolev-type equations). Discretization of time and space variables is conducted on the basis of the finite element method. The parameters of the scheme allow choosing the best approximation and accuracy, and an economic algorithm for numerical implementation. Theorems on the stability and convergence of the considered difference schemes are obtained.


(R1493) Discussion On Stability And Hopf-Bifurcation Of An Infected Prey Under Refuge And Predator, Moulipriya Sarkar, Tapasi Das Dec 2021

(R1493) Discussion On Stability And Hopf-Bifurcation Of An Infected Prey Under Refuge And Predator, Moulipriya Sarkar, Tapasi Das

Applications and Applied Mathematics: An International Journal (AAM)

The paper deals with the case of non-selective predation in a partially infected prey-predator system, where both the susceptible prey and predator follow the law of logistic growth and some preys avoid predation by hiding. The disease-free preys get infected in due course of time by a certain rate. However, the carrying capacity of the predator population is considered proportional to the sum-total of the susceptible and infected prey. The positivity and boundedness of the solutions of the system are studied and the existence of the equilibrium points and stability of the system are analyzed at these points. The effect …


(R1412) Stability And Bifurcation Of A Cholera Epidemic Model With Saturated Recovery Rate, Huda Abdul-Satar, Raid K. Naji Dec 2021

(R1412) Stability And Bifurcation Of A Cholera Epidemic Model With Saturated Recovery Rate, Huda Abdul-Satar, Raid K. Naji

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a Cholera epidemic model is proposed and studied analytically as well as numerically. It is assumed that the disease is transmitted by contact with Vibrio cholerae and infected person according to dose-response function. However, the saturated treatment function is used to describe the recovery process. Moreover, the vaccine against the disease is assumed to be utterly ineffective. The existence, uniqueness and boundedness of the solution of the proposed model are discussed. All possible equilibrium points and the basic reproduction number are determined. The local stability and persistence conditions are established. Lyapunov method and the second additive compound …


(R1458) A New Finite Difference Scheme For High-Dimensional Heat Equation, Jafar Biazar, Roxana Asayesh Dec 2021

(R1458) A New Finite Difference Scheme For High-Dimensional Heat Equation, Jafar Biazar, Roxana Asayesh

Applications and Applied Mathematics: An International Journal (AAM)

In this research‎, ‎a new second-order finite difference scheme is proposed to solve two and three- dimensional heat equation‎. Finite difference equations are determined via a discretization approach in which spatial second order partial derivatives in x and y directions are approximated simultaneously‎ while in the classic method, each spatial partial derivative is replaced by a central finite difference approximation, separately. By this new discretization scheme and also using the forward difference to the first-order time derivative, a finite difference equation is obtained for the parabolic equation. This approach is explicit and similar to other explicit approaches, an interval for …


(R1464) Stability Of The Artificial Equilibrium Points In The Low-Thrust Restricted Three-Body Problem With Variable Mass, Amit Mittal, Krishan Pal, Pravata Kumar Behera, Deepak Mittal Dec 2021

(R1464) Stability Of The Artificial Equilibrium Points In The Low-Thrust Restricted Three-Body Problem With Variable Mass, Amit Mittal, Krishan Pal, Pravata Kumar Behera, Deepak Mittal

Applications and Applied Mathematics: An International Journal (AAM)

In this article, we have investigated the existence and stability of the artificial equilibrium points (AEPs) in the low-thrust restricted three-body problem with variable mass. In this model of the low-thrust restricted three-body problem, we have considered both the primaries as point masses. The mass of the spacecraft varies with time according to Jeans’ law (1928). We have introduced a new concept for creating the AEPs in the restricted three-body problem with variable mass using continuous constant acceleration. We have derived the equations of motion of the spacecraft after using the space-time transformations of Meshcherskii. The AEPs have been created …


Research On Flexible Job-Shop Dynamic Scheduling Based On Game Theory, Yichen You, Wang Yan, Zhicheng Ji Nov 2021

Research On Flexible Job-Shop Dynamic Scheduling Based On Game Theory, Yichen You, Wang Yan, Zhicheng Ji

Journal of System Simulation

Abstract: To quickly and effectively respond to the machine fault disturbance events in Flexible Job-shop Scheduling Problem (FJSP), a flexible job-shop dynamic scheduling based on game theory is established. A pre-scheduling scheme is generated under Non-Dominated Sort Genetic Algorithm-Ⅱ (NSGA-Ⅱ) algorithm which introduces self-adapted crossover operators to improve the population diversity. For FJSP dynamic scheduling with machine fault, a multi-stage complete information game model is built to better balance the stability and robustness indicators and respond quickly to the machine fault, in which the stability and robustness indicators are mapped to the game players, and a hybrid Nash Equilibrium which …


Stability-Delay Efficient Cluster-Based Routing Protocol For Vanet, Ahmed Jawad Kadhim Al-Shaibany Ph.D Aug 2021

Stability-Delay Efficient Cluster-Based Routing Protocol For Vanet, Ahmed Jawad Kadhim Al-Shaibany Ph.D

Karbala International Journal of Modern Science

Vehicular Ad hoc Network (VANET) can be used in safety applications to transfer information about some events (e.g. accidents) with minimum time. Sending this information is achieved by using a routing algorithm. A large number of cluster-based routing schemes were presented for VANET. Unfortunately, the mobility of vehicles in unexpected directions negatively affects the performance of these schemes, destroys the network links, and decreases the routes' stability. This problem leads to repeat route discovery and maintenance operations and, as a result increases the overhead and delay. Thus, they are not an optimal selection for safety applications. Moreover, the cluster-based policies …


Study On Universal Characteristics Of Insect Population Ecological Network, Guilan Luo, Hongjun Hao, Wang Xiao, Zhang Mei Jul 2021

Study On Universal Characteristics Of Insect Population Ecological Network, Guilan Luo, Hongjun Hao, Wang Xiao, Zhang Mei

Journal of System Simulation

Abstract: In order to evaluate the current state of insect ecological development in Erhai wetland, complex network theory is used to construct a topological structure model of insect ecological network with insect populations as network nodes and correlations as edges. By analyzing the characteristic parameters of the model, it is concluded that the insect ecological network conforms to the characteristics of small world and scale-free network, and the node degree distribution obeys the power law distribution. The method of destroying the topology is used to simulate the dynamic evolution of the network ecology. The study shows that the disappearance of …


Numerical Calculation Of Lyapunov Stable Solutions Of The Hyperbolic Systems, Dilfuza Ne'matova, Aziza Akbarova Jun 2021

Numerical Calculation Of Lyapunov Stable Solutions Of The Hyperbolic Systems, Dilfuza Ne'matova, Aziza Akbarova

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

We give numerical examples demonstrating and confirming the theoretical results obtained for systems of two linear hyperbolic equations.


Qualitative Analysis Of A Modified Leslie-Gower Predator-Prey Model With Weak Allee Effect Ii, Manoj K. Singh, B. S. Bhadauria Jun 2021

Qualitative Analysis Of A Modified Leslie-Gower Predator-Prey Model With Weak Allee Effect Ii, Manoj K. Singh, B. S. Bhadauria

Applications and Applied Mathematics: An International Journal (AAM)

The article aims to study a modified Leslie-Gower predator-prey model with Allee effect II, affecting the functional response with the assumption that the extent to which the environment provides protection to both predator and prey is the same. The model has been studied analytically as well as numerically, including stability and bifurcation analysis. Compared with the predator-prey model without Allee effect, it is found that the weak Allee effect II can bring rich and complicated dynamics, such as the model undergoes to a series of bifurcations (Homoclinic, Hopf, Saddle-node and Bogdanov-Takens). The existence of Hopf bifurcation has been shown for …


Covid-19 Modeling With Caution In Relaxing Control Measures And Possibilities Of Several Peaks In Cameroon, S. Y. Tchoumi, Y. T. Kouakep, D. J. Fotsa Mbogne, J. C. Kamgang, V. C. Kamla, D. Bekolle Jun 2021

Covid-19 Modeling With Caution In Relaxing Control Measures And Possibilities Of Several Peaks In Cameroon, S. Y. Tchoumi, Y. T. Kouakep, D. J. Fotsa Mbogne, J. C. Kamgang, V. C. Kamla, D. Bekolle

Applications and Applied Mathematics: An International Journal (AAM)

We construct a new model for the comprehension of the Covid-19 dynamics in Cameroon. We present the basic reproduction number and perform some numerical analysis on the possible outcomes of the epidemic. The major results are the possibilities to have several peaks before the end of the first outbreak for an uniform strategy, and the danger to have a severe peak after the adoption of a careless strategy of barrier anti-Covid-19 measures that follow a good containment period.


Aspect Ratio Dependent Air Stability Of Pbse Nanorods And Photovoltaic Applications, Demet Asi̇l, Tuğba Haciefendi̇oğlu Jan 2021

Aspect Ratio Dependent Air Stability Of Pbse Nanorods And Photovoltaic Applications, Demet Asi̇l, Tuğba Haciefendi̇oğlu

Turkish Journal of Chemistry

Development of unique strategies to overcome Shockley-Queisser (SQ) limit in solar cells has gained a great deal of interest. Multiple exciton generation (MEG) process has been considered as one of the best approaches to the SQ limitation. In this respect, PbSe quantum dots (QDs) and nanorods (NRs) have been regarded as promising solar energy harvesting materials owing to their noticeable MEG yields. Although air stability has been regarded as one of the main disadvantage of PbSe QDs, no study has pointed out to the air sensitivity of PbSe NRs yet. Here, we reveal the effect of aspect ratio on air …


Quercetin Enhances Vitamin D2 Stability And Mitigate The Degradation Influenced By Elevated Temperature And Ph Value, Sukkum Ngullie Chang, Jeong Jun Lee, Hyun Jin Kim, Sun Chul Kang Jan 2021

Quercetin Enhances Vitamin D2 Stability And Mitigate The Degradation Influenced By Elevated Temperature And Ph Value, Sukkum Ngullie Chang, Jeong Jun Lee, Hyun Jin Kim, Sun Chul Kang

Turkish Journal of Chemistry

Vitamin D2 (vit. D2) is a nutraceutical essentially needed for good health. However, it is susceptible to oxygen and high temperature. The use of natural products such as bioflavonoids possessing anti-degradative effect of vit. D2 degradation has not been described before. A combinational effect of vit. D2 with quercetin showed a positive effect and inhibited vit. D2 degradation when exposed to high temperature (50 oC and 75 oC) at different time points. The results obtained revealed vit. D2 degradation was drastically increased with longer incubation under thermal treatment. However, quercetin and vit. D2 groups were able to significantly inhibit the …