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Analysis of highly efficient perovskite solar cells with inorganic hole transport material

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Chinese Physics B 2019年第12期28卷 393-399页

作者： i Kabir S A Mahmood Department of Electrical and Electronics Engineering Bangladesh University of Engineering and Technology

Organo-halide perovskites in planar heterojunction architecture have shown considerable promise as efficient light harvesters in solar cells. We carry out a numerical modeling of a planar lead based perovskite solar cell(PSC) with Cu2ZnSnS4(CZTS) as the hole transporting material(HTM) using the one-dimensional solar cell capacitance simulator(SCAPS-1 D). The effects of numerous parameters such as defect density, thickness, and doping density of the absorber layer on the device performance are investigated. The doping densities and electron affinities of the electron transporting material(ETM) and the HTM are also varied to optimize the PSC performance. it has been observed that a thinner absorber layer of220 nm with a defect density of 1014 cm-3 compared to the reference structure improves the device performance. When doping density of the absorber layer increases beyond 2×1016 cm-3, the power conversion efficiency(PCE) reduces due to enhanced recombination rate. The defect density at the absorber/ETM interface reduces the PCE as well. Considering a series resistance of 5 ?·cm2 and all the optimum parameters of absorber, ETM and HTM layers simultaneously, the overall PCE of the device increases significantly. in comparison with the reference structure, the PCE of the optimized device has been increased from 12.76% to 22.7%, and hence the optimized CZTS based PSC is highly efficient.

关键词： CH3NH3Pbi3 Cu2ZnSnS4(CZTS) SCAPS-1D absorption coefficient

Susceptibility to Hot Cracking and Weldment Heat Treatment of Haynes 230 Superalloy

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Journal of Materials Science & Technology 2006年第5期22卷 685-690页

作者： i.K.Lee Department of Mechatronic Technology National Taiwan Normal University TaipeiTaiwanChina

This study investigates the susceptibility of hot cracking and weldment heat treatment of Haynes 230 superalloy. The Varestriant test was conducted to evaluate this susceptibility. Welding was performed by gas tungsten arc welding （GTAW） and plasma arc welding （PAW） with stress relief heat treatment and solid solution heat treatment. A tensile test is then performed to measure the changes in the mechanical properties of the heattreated material. The results indicate that the number of thermal cycles does not affect the susceptibility of Haynes 230 superalloy to hot cracking. However, it does increase the strain. in weldment of heat treatment, stress relief annealing increases the yield strength and tensile strength of the welded parts. The section of the tensile specimens shows fibrous fractures on the welded parts, regardless of whether they are heat-treated.

关键词： Haynes 230 super alloy Varestriant test Hot cracking Susceptibility Stress relief annealing

Electrical and dielectric characterization of Au/ZnO/n-Si device depending frequency and voltage

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Chinese Physics B 2017年第2期26卷 477-483页

作者： i Orak A Kocyigit S Ahndal Bingol University Vocational School of Health Services 12000 Bingol Turkey Bingol University Faculty of Sciences and Arts Department of Physics 12000 Bingol Turkey igdir University Engineering Faculty Department of Electrical Electronic Engineering 76000 Igdir Turkey Gazi Universty Faculty of Sciences Department of Physics 06500 Ankara Turkey

Au/Zn O/n-type Si device is obtained using atomic layer deposition（ALD） for Zn O layer, and some main electrical parameters are investigated, such as surface/interface state（Nss）, barrier height（Φb）, series resistance（Rs）, donor concentration（Nd）, and dielectric characterization depending on frequency or voltage. These parameters are acquired by use of impedance spectroscopy measurements at frequencies ranging from 10 k Hz to 1 MHz and the direct current（DC） bias voltages in a range from-2 V to ＋2 V at room temperature are used. The main electrical parameters and dielectric parameters,such as dielectric constant（ε＂）, dielectric loss（ε＂）, loss tangent（tan δ）, the real and imaginary parts of electric modulus（M and M）, and alternating current（AC） electrical conductivity（σ） are affected by changing voltage and frequency. The characterizations show that some main electrical parameters usually decrease with increasing frequency because charge carriers at surface states have not enough time to fallow an external AC signal at high frequencies, and all dielectric parameters strongly depend on the voltage and frequency especially in the depletion and accumulation regions. Consequently, it can be concluded that interfacial polarization and interface charges can easily follow AC signal at low frequencies.

关键词： Au/ZnO/n–Si device dielectric properties polarization process frequency and voltage dependence

Experimental nuclear charge density and theoretical description of theabove-barrier light heavy-ion fusion process

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Chinese Physics C 2023年第8期47卷 64-74页

作者： i.i.Gontchar M.V.Chushnyakova Physics and Chemistry Department Omsk State Transport UniversityOmskRussia Physics Department Omsk State Technical UniversityOmskRussia

Theoretical modeling of nucleus-nucleus collisions is often based on the nucleus-nucleus *** of the advanced methods for constructing this potential is the semi-microscopical double-folding model with M3 YParis *** and neutron densities are significant components of this *** correct nucleon density(ND) must reproduce the experimental nuclear charge density(NCD).However,those who deal with modeling the fusion process typically disregard this *** aim to achieve a good description of both the nuclear charge density and above-barrier fusion cross sections of even-even light nuclei with Z=*** consider several versions of NDs available in literature and construct our own approximation for the ND of the even-even spherical nuclei^(12)C,^(16)O,and^(40)Ca,abbreviated as FE-density(Fermi+exponential).We carefully compare the NCDs resulting from different versions of NDs with the experimental *** finding the nucleus-nucleus potential using the double-folding model with the density dependent M3 Y-Paris NN-forces and FE densities,we evaluate the abovebarrier fusion cross sections for five reactions,^(12)C+^(12)C,^(12)C+^(16)O,^(16)O+^(16)O,^(16)O+^(40)Ca,and^(40)Ca+^(40)Ca,and40Ca+40Ca,for which experimental data are *** cross sections are calculated using two approaches:a) the barrier penetration model and b) the trajectory model with surface friction(TM).To find the transmission coefficients for the TM,the Langevin equations are *** all considered reactions,our TM typically reproduces the above-barrier experimental cross sections within 10-15%.The only adjustable parameter of the model,the optimal friction strength KRm,is found to be approximately 90 zs·GeV-1for the light reactions12C+12C,12C+16O,and16O+16O and approximately 15zs·GeV-1for the heavy reactions16O+40Ca and40Ca+*** latter findings are in reasonable agreement with the systematics found ***,the FE-recipe allows highly accurate and s

关键词： nuclear charge densities nucleon densities heavy-ion fusion surface friction double-fold-ing model

Hybrid Clustering Algorithms with GRASP to Construct an initial Solution for the MVPPDP

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Computers, Materials & Continua 2020年第3期62卷 1025-1051页

作者： Abeer i.Alhujaylan Manar i.Hosny Computer Science Department College of Computer and Information SciencesKing Saud UniversityRiyadhSaudi Arabia College of Computer Qassim UniversityBuraydahSaudi Arabia

Mobile commerce(m-commerce)contributes to increasing the popularity of electronic commerce(e-commerce),allowing anybody to sell or buy goods using a mobile device or tablet anywhere and at any *** demand for e-commerce increases tremendously,the pressure on delivery companies increases to organise their transportation plans to achieve profits and customer *** important planning problem in this domain is the multi-vehicle profitable pickup and delivery problem(MVPPDP),where a selected set of pickup and delivery customers need to be served within certain allowed trip *** this paper,we proposed hybrid clustering algorithms with the greedy randomised adaptive search procedure(GRASP)to construct an initial solution for the *** approaches first cluster the search space in order to reduce its dimensionality,then use GRASP to build routes for each *** compared our results with state-of-the-art construction heuristics that have been used to construct initial solutions to this *** results show that our proposed algorithms contribute to achieving excellent performance in terms of both quality of solutions and processing time.

关键词： Multi-vehicle profitable pickup and delivery problem K-means clustering algorithm ant colony optimisation greedy randomised adaptive search procedure metaheuristic algorithms

CP asymmetries in Strange Baryon Decays

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Chinese Physics C 2018年第1期42卷 16-22页

作者： i.i.Bigi 康现伟李海波 Department of Physics University of Notre Dame du Lac College of Nuclear Science and Technology Beijing Normal University institute of Physics Academia Sinica institute of High Energy Physics University of Chinese Academy of Science

While indirect and direct C P violation（CPV） has been established in the decays of strange and beauty mesons, no CPV has yet been found for baryons. There are different paths to finding C P asymmetry in the decays of strange baryons; they are all highly non-trivial. The Hyper CP Collaboration has probed CPV in the decays of singleΞ and Λ [1]. We discuss future lessons from e~＋e^-collisions at BESⅢ/BEPCⅡ： probing decays of pairs of strange baryons, namely Λ, Σ and . Realistic goals are to learn about non-perturbative QCD. One can hope to find CPV in the decays of strange baryons; one can also dream of finding the impact of New Dynamics. We point out that an important new era will start with the BESiii/BEPCii data accumulated by the end of 2018. This also supports new ideas to trigger J/ψ→■Λ at the LHCb collaboration.

关键词： CP asymmetry J/ψ decay hyperon decay BESⅢ/BEPCⅡ

Vertical seismic absorber utilizing inertance and negative stiffness implemented with gas springs

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Earthquake Engineering and Engineering Vibration 2023年第1期22卷 225-241页

作者： Kalogerakou M Paradeisiotis A Antoniadis i Dynamics and Structures Laboratory School of Mechanical EngineeringNational Technical University of Athens15780 AthensGreece

A novel implementation of negative stiffness elements(NSEs)is proposed,utilizing industrial grade nitrogen gas springs as pre-stressed stiffness elements in a configuration with lever *** NSE is combined with an inerter to form a stiff dynamic absorber(SDA)for vertical seismic protection of structures with base *** SDA is optimized to minimize vertical accelerations while ensuring static structural integrity,excellent damping performance and containment of relative *** introduction of gas springs in place of conventional linear springs addresses important practical limitations through features of non-linearity and industrial grade *** proposed implementation is dimensioned for a 50-ton structure and evaluated numerically for 25 actual earthquake records,in comparison with a linear SDA model and an equivalent conventional damper(CD).individual and averaged results of acceleration and displacement time histories demonstrate vastly superior response compared to CD regarding induced accelerations for similar *** equivalency with the linear SDA model indicates the stability of the gas spring implementation while guaranteeing predictability,tested endurance,proper tolerances,and off-axis motion resistance without requiring additional guiding components,as opposed to conventional *** features render the proposed implementation a promising solution for the realization of NSEs in seismic protection.

关键词： negative stiffness gas springs vertical seismic protection KDamper inerter

Applications and theoretical perspectives of artificial intelligence in the rate of penetration

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Petroleum 2022年第2期8卷 237-251页

作者： Chinedu i.Ossai Ugochukwu i.Duru Faculty of Health Arts and DesignSwinburne UniversityJohn Street HawthornVictoria3122Australia Federal University of Technology Owerri Nigeria

Artificial intelligence(Ai)is becoming popular for the Rate of Penetration(ROP)estimation,hence,the need to study the best techniques and their advantages over empirical *** literatures were analysed to determine the prevalence of Ai in ROP computation and compare the computation accuracies with empirical *** Neural Network(ANN)accounted for over 92%of the Ai techniques used for ROP computation and Weight on Bit(WOB)mostly influenced the computation *** accuracy of Ai algorithms is better than the empirical models thus,will improve the drilling efficiency,reduce cost and enhance the development of pad wells.

关键词： Artificial intelligence Drilling operations Rate of penetration optimization Artificial neural network Weight on bit

Effects of a structurally related substance on the crystallization of paracetamol

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 79-87页

作者： Ali SALEEMi i.i. ONYEMELUKWE Zoltan NAGY Department of Chemical Engineering Loughborough University Loughborough LE11 3TU UK School of Chemical Engineering Purdue University West Lafayette Ind. 47907 USA

Paracetamol （PCM） was crystallized from an isopropanol （iPA） solution containing various small amounts of metacetamol as an additive. The effect on the nucleation kinetics was studied by measuring the induction time to nucleation and the metastable zone width using focused beam reflectance measurements （FBRM） and attenuated total reflectance （ATR-UV/Vis） spectroscopy. Both the induction time and the metastable zone width were expressed as functions of the additive concentration. Small amounts ofmetacetamol （1-4 tool-%） were found to cause significant inhibition to the nucleation by extending both the induction time and the metastable zone width. A progressive change in the morphology of the paracetamol crystals from tabular to columnar habit was observed with increasing metacetamol concentration. The solvent also had a significant effect on the size of the paracetamol crystals as smaller crystals were obtained in iPA than in aqueous solution. The dissolution rate of paracetamol was improved by the incorporation of metacetamol with 4 tool-% having the most effect. A supersaturation control （SSC） approach was implemented for the PCM-iPA system with and without metacetamol in an attempt to control and obtain larger metacetamol-doped paraeetamol crystals.

关键词： acetaminophen metacetamol crystallization metastable zone width induction time supersaturation control