bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesization and optical characterization of photovoltaic materials for perovskite solar cell application
Authors: Dongre Y K , Roy P , Khare A , Tiwari S 
Published: April 2021

Abstract
The performance of Perovskite solar cells (PSCs) has rapidly increased over the last decade. The power conversion efficiency (PCE) of 25.2% has been reported. Drastic and rapid change in PCE of PSCs has attracted a lot of attention toward this alternative photovoltaic technology that can be manufactured using simple and low cost processing techniques, over the traditional silicon solar technology. Here in this work, we have synthesized Molybdenum trioxide (MoO3) and Titanium dioxide (TiO2) for charge transport materials application in PSC application. The analysis of materials has been carried out by photoluminescence and absorbance spectra. The results signify that MoO3 has absorbed at the visible region around (600-800) nm and the absorbance of TiO2 tuned at 400 nm. Due to high absorption range (600-800) at visible region MoO3 is suitable for Hole Transport Material (HTM). The widely used Electron Transport Material (ETM) TiO2 is also synthesized and characterized.
Impact of hole transport layer on the performance of all-inorganic tin (Sn) based perovskite solar cells
Authors: Roy P , Dongre Y K , Tiwari S , Chaturvedi D , Khare A 
Published: April 2021

Abstract
The power conversion efficiency (PCE) of perovskite solar cells (PSCs) has shown vast increment from 3.81% to 25.5% within a decade. Despite the fast progress and many advantages, these cells are facing an issue of toxicity and poor device stability. In this work, we deal with the issue of toxicity by using Tin (Sn) instead of Lead (Pb). The PSCs are simulated using Solar Simulator Capacitor (SCAPS-1D version 3.3.07) software. We used all-inorganic, lead free material, Cesium Tin–Germanium Tri-iodide (CsSn0.5Ge0.5I3) as an absorber material. We further investigate the influence of hole transport layer (HTL) on the performance of Sn based PSCs. Simulation and analysis of following CsSn0.5Ge0.5I3 based PSC devices have been done: using (i) HTL free configuration (ii) inorganic HTL and (iii) organic HTL. The simulated cells are in planar n-i-p architecture. This work depicts the fact that Sn based PSCs have a potential to serve as high performance solar cells. The results signifies the impact of HTL on the performance of PSCs, in this study, we also suggest alternatives to the widely used HTM (Spiro-OMeTAD) that not only produce comparable photovoltaic performance but also are cost effective. We also analyse the influence of using various metal cathodes on the simulated cell. The result suggests that presence and type of HTM is having an impact on the contact selection criteria. The influence of HTL thickness variation on the performance of the PSCs are also studied.
Simulation and analysis of schottky junction perovskite solar cells (SJPSCs)
Authors: Sinha Numeshwar Kumar , Roy Priyanka , Ghosh Dhriti Sundar , Khare Ayush 
Published: April 2021

AbstractThe Schottky junction solar cells are the simplest and single-layer structure of solar cells, offering low-cost and easy fabrication. In this study, we have simulated and analyzed the Schottky junction perovskite solar cells, having the device structure of FTO/MAPbI3/Au. The simulation has done by Solar Cell Capacitance Simulator (SCAPS-1D). In this simulation, we have studied the effect of an absorber layer thickness, doping density, defect density, and the cell’s temperature on the performance of the cells. We have further studied the effect of different back electrodes, like Au, Cu, Ag, Al, and Graphene in the performance of cells. The effect of series and shunt resistance has also been studied at optimized parameters. This simulation suggests that the SJPSCs show the highest optimized power conversion efficiency of greater than 14%, at actual series and shunt resistance of the cell. Simulating this simplest structure will help to further improvement in the performance of SJPSC. However, the use of lead makes the solar cells non-eco-friendly, but the proper encapsulation and disposal management can solve this problem.
Observation of coronal mass ejections in association with sun spot number and solar flares
Authors: Gour Preetam Singh , Singh Nitin P , Soni Shiva , Saini Sapan Mohan 
Published: April 2021

Abstract
The sun’s atmosphere is frequently disrupted by coronal mass ejections (CMEs) coupled with different solar happening like sun spot number (SSN), geomagnetic storms (GMS), solar energetic particle and solar flare. CMEs play the important role in the root cause of weather in earth’s space environment among all solar events. CMEs are considered as the major natural hazardous happening at the surface of sun because this event can cause several other phenomena like solar flare and many more. In this work, we report a statistical observation for the relationship of CMEs having linear speed >500 km/s with SSN and solar flares that were registered during the period 1997-2015. Test results of the annual correlation between SSN and CMEs is 0.77 and can be represented by a linear regression equation. We concluded that SSN and solar flares are well correlated with CMEs in most of the yearly compiled data for this time span.
DFT study of adsorption and diffusion of Mg, K, Ca over monolayer antimonene
Authors: Upadhyay S , Srivastava P 
Published: April 2021

Abstract
Density Functional theory (DFT) based calculations are carried out to investigate adsorption and diffusion properties of Magnesium (Mg), Potassium (K) and Calcium (Ca) over single layer antimony (Sb) i.e. antimonene. Ca has highest value of absolute adsorption energy followed by K and Mg respectively. Charge transfer is greater in case of K adsorbed antimonene as compared to both of the other metals. This affects the electronic properties such as bandstructure and density of states. Antimonene is semiconducting in its pristine form. The adsorption of K leads to a shift to metallic nature, whereas Mg and Ca adsorption still maintain the semiconducting nature after reducing the bandgap. Diffusion of these metals shows that K can easily diffuse through the antimonene surface as compared to the Mg and Ca. The value of diffusion barrier for Mg, K and Ca is 0.30, 0.12 and 0.43 eV respectively. The effective adsorption and charge transfer along with low values of diffusion barrier suggests that phosphorene can be explored further as potential candidate for metal-ion batteries.
Study of adsorption of methylene blue in aqueous solution onto activated carbon prepared using low cost domestic oven based heating system
Authors: Sahoo Sinmay , Devi Maya , Kumar Das Susanta 
Published: April 2021

Abstract
In this work activated carbon was prepared from teak wood charcoal using very low-cost oven based heating system. Firstly, charcoals were grinded with a domestic grinder and then activated with 25% CaCl2 solution and then heated with 250C for different times. And then experiment was carried out through 2.5 × 10-5 methylene blue aqueous solution by taking activated Charcoal into it and kept one hour for adsorption. Adsorption capacity was estimated by taking the different amount of activated carbon. The result indicates that prepared activated carbon be effectively used for water purification application through adsorption of the dye.
131I radioactive self-expandable metallic stents for the therapy of malignant biliary obstruction
Authors: Liu Meirong , Hou Mengfei , Wu Qinghe , Zhang Chunfu 
Published: April 2021

Abstract
Biliary stent implantation has become a standard approach for patients with unresectable malignant biliary obstruction. Unfortunately, in-stent restenosis after stent implantation still occurs because of tumor overgrowth. The majority of studies show that radioactive stents harbor both the obstructed biliary tract-dilating and tumor-suppressing functions. In this study, we designed a kind of novel 131I-labeled radioactive self-expandable metallic stent (SEMS) that combines the mechanical dilation forces induced by stent expansion and 131I intraluminal brachytherapy, which was prepared by first coating the SEMS with poly (diallyl acrylate) (PDA) and then labeling with iodine-131. The designed stents would not only have a longer patency time but also is able to inhibit biliary compression caused by tumor growth. The PDA coating was robust and flexible. The 131I labeling rate was about 60%, and after a 16-day test of radiochemical stability of 131I, the radioactive stability was around 80%. In addition, the radiochemical stability of 131I could be improved by PDA recoating post-131I labeling. In conclusion, we designed and fabricated a kind of novel 131I-labeled radioactive self-expandable metal stents by labeling 131I on the PDA-coated stent. We provide a new idea of radioactive stents design, which would extend the patency time of the stent while reducing the rate of stent restenosis after implantation.
Study on performance improvement of oil well cement slurry by poly ether ether ketone
Authors: You Fuchang , Tian Jin , Shu Man 
Published: April 2021

Abstract
After the oil well cement solidifies, the internal original void causes the inherent strength of the cement stone to be insufficient, and the structural integrity of the cement stone is damaged after the external load, which is not conducive to the subsequent oil and gas exploitation. In order to make up for the inherent deficiency of cement paste strength, the effect of PEEK with high strength and high elastic modulus on the properties of oil well cement was studied. The conventional properties and mechanical properties of PEEK cement paste with different contents were evaluated. The microstructure of PEEK cement paste was observed by scanning electron microscope. The experimental results show that compared with the cement paste without peek, the rheological properties of cement paste with 1% ∼ 6% peek are worse, the thickening time is shorter, and the water loss is reduced. After curing for 28 days, the compressive strength of 5% peek cement paste decreased by 15%, the flexural strength and impact strength increased by 21% and 11% respectively, and the elastic modulus decreased by 50%. Peek is uniformly dispersed and filled in the cement paste. When the cement paste is subjected to external load, peek will deform, absorb part of the energy and hinder the crack propagation, which improves the ability of the cement paste to resist external load.
Experimental research on four-point-bending loading of composite fuselage frame
Authors: Xiang Li , Xingfu Li 
Published: April 2021

Abstract
A four-point-bending loading test device was designed for the pure bending loading of the composite fuselage curved frame. The reinforcing subplates, reinforcing frames, wedge-shaped blocks and other parts were installed in the load segment of test pieces to enhance the local stiffness, strength and torsional stiffness. Four-point-bending loading tests and nonlinear finite element calculation of C-frame and Z-frame pieces under the condition of positive bending was carried out. The calculated buckling mode was in good agreement with the test result, which provides a certain theoretical basis for the instability mode analysis of curved frames. The test and analysis results show that under the condition of positive bending and the middle section of C-frame has lateral instability and the end inner edge of the frame has the local buckling and damage. While the middle section of inner edge of the Z-frame has only local buckling and damage. The test results of two kinds of frame show that the stability and structural strength of Z-frame are better than that of C-frame.
Effects of reuse on the properties of tantalum powders and tantalum parts additively manufactured by electron beam powder bed fusion
Authors: Guo Yu , Chen Chao , Wang Qiangbing , Liu Min 
Published: April 2021

Abstract
The cost of additively manufactured tantalum parts can be effectively lowered by reusing or recycling tantalum powder. To evaluate the effects of reuse of the tantalum powder on the properties of tantalum parts and scaffolds, this study investigated the characteristics of tantalum powder during cycling, including oxygen content, particle morphology, apparent density, tap density, and flowability. Besides, the influence of reuse time on the mechanical properties of electron beam powder bed fusion (EB-PBF) fabricated tantalum parts and scaffolds was studied with tantalum powder reused more than 30 cycles. The results indicated that particle size distribution of the tantalum powder was nearly unchanged with the increase of cycle number, accordingly apparent density, tap density, and fluidity. While the powder became less spherical with increasing reuse times and some particles showed noticeable distortion and rough surface after being reused 25 times. Moreover, the oxygen content of the tantalum powder increased progressively with increasing reuse times, leading to the decrease of plasticity of the dense tantalum after 15 reuse cycles, and some potential micro-defects appeared in the tantalum samples fabricated from EB-PBF process. However, the tensile strength of dense tantalum parts was not sensitive to the number of uses within the research range.
Thermostructural and fluorescence properties of enterolobium cyclocarpum extract embedded in a silica xerogel matrix
Authors: Martínez J R , Ortega-Zarzosa G , Nieto-Villena A , Velázquez Pérez S E , Montiel-Palma S , Herrera-González A M , Galván-García E , Guerrero A Lobo 
Published: April 2021

AbstractThis work deals with the fluorescence behavior exhibited by extracts of parota wood (enterolobium cyclocarpum) when are embedded in a silica matrix, and the effect of the temperature on the emission and structural properties. The organics were incorporated into a silica matrix using the sol-gel method, and the resulting hybrid composite was subjected to different heat treatments to study its thermal stability and the effect on their structural and fluorescence properties. The structural properties were studied using x-ray diffraction (XRD), and the organics were analyzed by infrared spectroscopy (FT-IR) and fluorescence spectroscopy. Results show that the silica matrix avoids the thermal decomposition of the organics, and the structural changes of the silica impact on the fluorescence properties. In this sense, the maximum emission obtained at 400 °C was three times higher than the RT. This behavior was attributable to the strong interactions between the cellulosic compounds and the silica. Also, the cellulosic compounds promote the formation of open Si-O arrangements.
Precision integration of grating-based polarizers onto focal plane arrays of near-infrared photovoltaic detectors for enhanced contrast polarimetric imaging
Authors: Feng Bo , Chen Yifang , Sun Duo , Yang Zongyao , Yang Bo , Li Xue , Li Tao 
Published: April 2021

Abstract
Polarimetric imaging enhances the ability to distinguish objects from a bright background by detecting their particular polarization status, which offers another degree of freedom in infrared remote sensing. However, to scale up by monolithically integrating grating-based polarizers onto a focal plane array (FPA) of infrared detectors, fundamental technical obstacles must be overcome, including reductions of the extinction ratio by the misalignment between the polarizer and the detector, grating line width fluctuations, the line edge roughness, etc. This paper reports the authors’ latest achievements in overcoming those problems by solving key technical issues regarding the integration of large-scale polarizers onto the chips of FPAs with individual indium gallium arsenide/indium phosphide (InGaAs/InP) sensors as the basic building blocks. Polarimetric and photovoltaic chips with divisions of the focal plane of 540 × 4 pixels and 320 × 256 superpixels have been successfully manufactured. Polarimetric imaging with enhanced contrast has been demonstrated. The progress made in this work has opened up a broad avenue toward industrialization of high quality polarimetric imaging in infrared wavelengths.
Research on the selection and layout of the cantilever sensor based on photoacoustic spectroscopy gas detection technology
Authors: Cheng Hongtu , Zhang Xiaoxing , Tang Ju , Xiao Song , Mao Shiyi , Wang Dibo , Zhuo Ran 
Published: April 2021

Abstract
Gas detection has become an indispensable part of the power equipment maintenance. Because of many advantages, cantilever enhanced photoacoustic(PA) spectroscopy was studied by many researchers. In this paper, with the help of Finite Element Method (FEM) simulations with the commercial software COMSOL, we have analyzed the distribution of the sound pressure inside the gas cell, in addition, we have analyzed the relationship between the Young’s modulus and size of the cantilever beam and its deformation, the relationship between the cantilever size and its eigen-frequencies were also obtained. Besides, we have performed the experiment of the deformation measurement. The results show that: for the gas cell, when it works at the first order resonance frequency, the maximum value of the sound pressure appears at the geometric center. For the main resonance cavity, with its length and radius increase, the first order resonance frequency of the gas cell decreases. Under the condition of ideal linear sound source, as the length and radius of the main resonance cavity changes, in the frequency domain, the sound pressure response curve changes, the maximum sound pressure corresponds the PA cell with 85 mm in length and 2 mm in radius. For the cantilever beam, with the increase of the Young’s modulus, the deformation decreases. The deformation is proportional to the fourth power of the length, whereas it is inversely proportional to the width and inversely proportional to the third power of the thickness. However, the experimental results showed that there may be a deviation in the vibration measurements by the vibration meter. As for the first order eigen-frequency, it is negatively correlated with the length and positively correlated with the thickness, but independent of the width. With the increase of the distance between the sound source and the cantilever beam, the deformation decreases.
Response of quantum spin networks to attacks
Authors: Sundar Bhuvanesh , Walschaers Mattia , Parigi Valentina , Carr Lincoln D 
Published: April 2021

Abstract
We investigate the ground states of spin models defined on networks that we imprint (e.g., non-complex random networks like Erdos–Renyi, or complex networks like Watts–Strogatz, and Barabasi–Albert), and their response to decohering processes which we model with network attacks. We quantify the complexity of these ground states, and their response to the attacks, by calculating distributions of network measures of an emergent network whose link weights are the pairwise mutual information between spins. We focus on attacks which projectively measure spins. We find that the emergent networks in the ground state do not satisfy the usual criteria for complexity, and their average properties are captured well by a single dimensionless parameter in the Hamiltonian. While the response of classical networks to attacks is well-studied, where classical complex networks are known to be more robust to random attacks than random networks, we find counter-intuitive results for our quantum networks. We find that the ground states for Hamiltonians defined on different classes of imprinted networks respond similarly to all our attacks, and the attacks rescale the average properties of the emergent network by a constant factor. Mean field theory explains these results for relatively dense networks, but we also find the simple rescaling behavior away from the regime of validity of mean field theory. Our calculations indicate that complex spin networks are not more robust to projective measurement attacks, and presumably also other quantum attacks, than non-complex spin networks, in contrast to the classical case. Understanding the response of the spin networks to decoherence and attacks will have applications in understanding the physics of open quantum systems, and in designing robust complex quantum systems—possibly even a robust quantum internet in the long run—that is maximally resistant to decoherence.
Application of candle soot CNPs-TiO2-PVP composite in the detection of volatile organic compounds with aldehyde, amine and ketone functional groups by resistance and impedance responses
Authors: Olifant G E , Kondiah K , Mamo M A 
Published: April 2021

Abstract
We have fabricated a solid-state gas sensor using a composite sensor layer made up of three different sensing materials namely; candle soot Carbon nanoparticles, Titanium dioxide and Poly (vinyl) pyrrolidone (PVP). The study was carried out to study the sensor’s response towards butyraldehyde, diethylamine and isobutyrophenone vapour at room temperature. The sensor was prepared by mixing candle soot CNPs, TiO2 and PVP in dimethylformamide using the ratio (2:1:3) respectively. The sensing materials were characterised using Brunauer–Emmett–Teller (BET), x-ray diffraction (XRD), Transmission and Scanning Electron Microscopy (TEM, SEM). The sensor’s response was measured by injecting a volume of 1 to 5 μl of each liquid analyte in a round-bottomed glass and an LCR metre was used to measure the ∆R and ∆Z responses. In both parameters, the sensor responded well to the different analytes, the response of the sensor linearly increases as the analyte vapour concentration increases. The sensors were discovered to exhibit more sensitivity of 0.07 Ω ppm−1 towards diethylamine in ∆R response and it was more sensitive towards isobutyrophenone in ∆Z response giving a sensitivity of 0.14 Ω ppm−1 while Butyraldehyde had the fastest response time of 145 s and Diethylamine had the fasted recovery time 130 s.