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Simulation and Design Implementation of Low-Cost and High-Efficiency Perovskite Solar Cells
Get PDFThe generation of low-cost electricity using renewable energy sources such as photovoltaic and wind power to replace fossil-fuel electrical power generation has grown to be an extensive and crucial area of research because of global warming. Recent research efforts range from the use of organic and inorganic materials to the incorporation of hybrid organic-inorganic materials in the fabrications of perovskite solar cells.
A perovskite photovoltaic is a kind of solar cell that incorporates a compound with a structure, usually a hybrid organic-inorganic tin halide or lead material base, as the light-collecting active layer. Photovoltaic devices using perovskites, for example, methylammonium lead iodide (CH3NH3PBI3) based materials, are generally easy to fabricate compared to silicon-based devices. Because of their characteristics, such as long diffusion lengths of holes and electrons, high carrier mobility, broad absorption range of the light spectrum, and long carrier lifetime, perovskites have had a significant impact in the solid-state solar cell research industry.
The goal of this study is to determine the proper selection of the perovskite-based solar cell\u27s ohmic electrode material (Au (Gold), Ag (Silver), Al (Aluminum), Cu (Copper), Cr (Chromium), Pt (Platinum), and Cu-graphite alloy), and the electron transport layer (TiO2, ZnO) while keeping the type of perovskite material the same. Photovoltaic devices are then fabricated using the chosen materials. The SCAPS 1-D simulation technology is used to study the thickness used in the methylammonium cations, a usual photovoltaic layer that may separate into a metastable plane of methyl iodide or iodomethane- lead ion (CH3l-Pb2) defects and trapped ammonia (NH3). Other metastable designs of the organic parts in (CH3NH3) PbI3-xClx are also included in the study. A fresh perspective in the comprehension of the auxiliary degradation, ionic transport, and charge trapping components in these materials are also studied. Additionally, the study considers the dynamics involved in the pulsed laser deposition (PLD) method, referred to as the MBMT-MAPLE/PLD technique for deposition. A variant of the MAPLE/PLD technique known as the concurrent multi-beam multi-target PLD forms a part of this work.
Each device is investigated through simulations using SCAPS ID and MATLAB software to determine the effects that the electrode and the electron transport layer (ETL) layer materials have on the efficiency of the device. Efficiencies of 27.2%, 26.47%, 18.86%, 25.61%, 22.73%, 27.2%, and 27.2% were obtained from the electrode materials Au (Gold), Ag (Silver), Al (Aluminum), Cu (Copper), Cr (Chromium), Pt (Platinum), and Cu-graphite alloy, respectively. The simulation results compared satisfactorily with fabricated devices results and other literature results which indicates that the simulation program is very accurate in predicting the device output parameters for other contact materials. Furthermore, the study demonstrates that as the work functions increased of the selected ohmic contacts, it will increase the solar cell output electrical parameters such as increased voltage and current and, thus, the efficiency and the filling factor (FF) of the devices
Synthesis, physicochemical investigations, DNA cleavage activity of biogenic zinc oxide nanoparticles and their interaction with Calf-Thymus DNA
No full textZinc oxide nanoparticles (ZnONps) have been broadly investigated for different biological applications because of their characteristic biocompatibility and antimicrobial action. Green synthesis approach was adopted to synthesize ZnONps utilizing Syzygium aromaticum bud extract. ZnONps showed a sharp band around 300 nm in UV–Vis spectrum, affirming their formation. The size of synthesized ZnONps was inspected by TEM which was found in 20–30 nm range. Average particle size was determined by Debye-Scherrer equation using PXRD spectrum. Interaction study of ZnONps with Calf-Thymus DNA have been investigated which has given significant results. The ZnONps have also shown 55% DNA cleavage activity against E.coli DNA
Generalized Hermite-based Apostol-Euler Polynomials and Their Properties
Get PDFThe aim of this paper is to study certain properties of generalized Apostol-Hermite-Euler polynomials with three parameters. We have shown that there is an intimate connection between these polynomials and established their elementary properties. We also established some identities by applying the generating functions and deduce their special cases and applications
Statistics of Branched Populations Split into Different Types
Get PDFSome population is made of n individuals that can be of P possible species (or types) at equilibrium. How are individuals scattered among types? We study two random scenarios of such species abundance distributions. In the first one, each species grows from independent founders according to a Galton-Watson branching process. When the number of founders P is either fixed or random (either Poisson or geometrically-distributed), a question raised is: given a population of n individuals as a whole, how does it split into the species types? This model is one pertaining to forests of Galton-Watson trees. A second scenario that we will address in a similar way deals with forests of increasing trees. Underlying this setup, the creation/annihilation of clusters (trees) is shown to result from a recursive nucleation/aggregation process as one additional individual is added to the total population
Classification of Some First Order Functional Differential Equations With Constant Coefficients to Solvable Lie Algebras
Get PDFIn this paper, we shall apply symmetry analysis to some first order functional differential equations with constant coefficients. The approach used in this paper accounts for obtaining the inverse of the classification. We define the standard Lie bracket and make a complete classification of some first order linear functional differential equations with constant coefficients to solvable Lie algebras.We also classify some nonlinear functional differential equations with constant coefficients to solvable Lie algebras
Image Encryption using Gingerbreadman Map And RC4A Stream Cipher
Get PDFDay to day increasing flow of sensitive or confidential information, such as images, audio, video, etc., over unsecured medium (like Internet) has motivated more concentration for concrete crypto algorithms. In this paper, an image encryption algorithm based on a permutation and substitution cipher has been proposed. In permutation stage, image pixels are shuffled using gingerbreadman map while in substitution stage, pixels are bit-wise XOR-ed with the keystream generated using RC4A (Rivest Cipher 4A) stream cipher algorithm. For the proposed scheme, statistical analyses, like histogram, adjacent pixels correlation coefficient, and information entropy are given. Security analyses, like key sensitivity, occlusion analysis are also given in this paper. The occlusion analysis shows that the proposed method is resistant to the occlusion attack. These statistical and security analyses support the concreteness of the proposed method
Vertical Motion of the Variable Infinitesimal Mass In the Circular Sitnikov Problem
Get PDFThe circular case of Sitnikov problem is studied here when the infinitesimal body varies its mass according to Jeans law and it is moving along the z-axis which is perpendicular to the orbital plane of the two equal spherical primaries. The two primaries are moving in xy-plane on the same circular path. These two primaries are imposing the Newtonian forces on the third variable mass body but not influenced by it. Stability of equilibrium points is examined followed by the derived equations of motion. The time-series solutions of the equation of motion are performed by using the Lindstedt-Poincaré method which is used to remove the secular term. We have numerically performed the time-series which shows that variation parameters have great impact on it
Soil CO2 emission in response to organic amendments, temperature, and rainfall
No full textVegetated land surfaces play an important role in determining the fate of carbon in the global carbon cycle. However, our understanding of the terrestrial biosphere on a global scale is subject to considerable uncertainty, especially concerning the impacts of climatic variables on the carbon cycle. Soil is a source and also a sink of CO2 exchange and helps in carbon sequestration. Agricultural management practices influence soil water dynamics, as well as carbon cycling by changing soil CO2 emission and uptake rates. The rate of soil CO2 emission varies for different crops and different organic amendments. The major goal of this study was to assess the impacts of the type and rate of organic amendment on soil CO2 emission in a collard greens crop grown in the southeast Texas environment. Thirty-six plots were developed to grow collard greens on Prairie View A&M University’s Research Farm. Three types of organic amendments (Chicken manure, Dairy manure, and Milorganite), at four levels of application (0, 168, 336, and 672 kg N/ha) were used and replicated three times. Each organic amendment type was applied to nine randomly selected plots. Three random plots were used as a control in each row. We measured daily soil CO2 emission for the first two weeks and every other day in a week during the experiment. We evaluated the effects of organic amendments and the application rates on soil CO2 emission for collard greens during two growing seasons. The results showed higher the application rates for each organic amendment, higher the CO2 emissions from the soil. The results also showed higher cumulative CO2 emissions for the soils amended with chicken manure and milorganite, but lowest for the soils amended with dairy manure. This field experiment and analyses help better understand the temporal and spatial variations of soil CO2 emission, and also help to develop best management practices to maximize carbon sequestration and to minimize soil CO2 emissions during the growth periods of collard greens under changing temperatures using different organic amendments, and application rates
Implementing And Electronic Provider Tool To Indentify Post- Partum Patients With Unintentional Dural Punctures: A Quality Improvement Project
No full textOne of the most frequent complications of regional anesthesia during labor is an unintentional dural puncture (UDP). While most patients that experience UDP do not develop complications and have an uneventful post-partum recovery, some women develop complications, such as a post-dural puncture headache (PDPH). The complications of a UDP can affect a new mother\u27s health, ability to care for her infant, and feelings regarding her post-partum recovery; therefore, it is essential for anesthesia providers to follow-up on patients with known UDP.
The objective of this quality improvement project was to change current practice for anesthesia providers regarding the identification of patients who had experienced UDP from regional anesthesia for labor at the practice site. The project supported the framework for the development and implementation of an electronic provider tool to appropriately identify patients.
This quality improvement project employed a pre-/post-study design to assess change in the documentation of UDPs by anesthesia providers following the implementation of an electronic health record (EHR) tool compared to paper logbooks.The study design also allowed for accurate measurement of UDP rates postimplementation of the electronic provider identification tool.
The overall findings confirrned a significant difference in the total number of identified UDP patients after the implementation of an electronic provider tool. In addition, a statistically significant difference between methods was observed (12 — 12.842, df= 1, p = \u3c .001). The proportion of patients identified with UDP in 2019 (n=36) was more than double that in 2019 (n=36) compared to 2017 (n=16) and 2018 (n=15) over the 6-month implementation period. Also, the percentage of UDPs recorded in the electronic provider tool was 3.4%, which was notably higher than the UDP rates in other current research studies.
The outcome of this quality improvement project was improved identification and documentation of UDP patients via the use of the electronic provider tool within the hospital\u27s EHR. This finding was consistent with improvements reported by other research studies that evaluated both the conversion from paper health records to EHR along with the evaluation of assessment tools used in EHR