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Analysis of the effect of bore centerline on projectile exit conditions in small arms

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Defence Technology（防务技术） 2022年第12期18卷 2160-2169页

作者： David Leonhardt Mark Garnich Miljenko Lucic College of engineering University of CanterburyPrivate Bag 4800Christchurch8140New Zealand Novacam Technologies Inc. 277 Lakeshore Road Suite#4Pointe-ClaireQuebecH9S 4L2Canada

Most finite element models of small arms focus on an idealized barrel,typically one with a perfectly straight bore *** five different experimentally measured bore centerlines,this investigation analyzes the effect centerline nonlinearity has on projectile exit *** includes the effect of rotating a centerline through several *** using Abaqus/Explicit,this dynamic analysis simulates a single firing cycle for each *** jump is calculated for each model as a measure of the effects of warped *** warped centerlines have a small effect on barrel dynamics.

关键词： Finite element analysis Small arms Barrel dynamics Bore centerline

Gas Line Pressure Fluctuation Analysis of a Gas-Liquid Reactor

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Journal of Thermal Science 2005年第3期14卷 267-271页

作者： J.J.J. CHEN J.C. ZHAO Chemical & Materials engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand ProfessorChemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

关键词：气体液体反应堆泡沫分配信号分析波动分析气液模型

Modeling of a Sn-Based HTM-Free Perovskite Solar Cell Using a One-Dimensional Solar Cell Capacitance Simulator Tool

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Transactions of Tianjin University 2023年第1期29卷 62-72页

作者： Eli Danladi Muhammad Kashif Andrew Ichoja Bikimi Bitrus Ayiya Department of Physics Federal University of Health SciencesPMB 145OtukpoBenue StateNigeria School of Electrical Automation and Information engineering Tianjin UniversityTianjin 300072China Faculty of engineering and Applied Technology Universal College of LearningPrivate Bag 11022Palmerston NorthNew Zealand

Tin(Sn)-based perovskite solar cells(PSCs)have received increasing attention in the domain of photovoltaics due to their environmentally friendly *** this paper,numerical modeling and simulation of hole transport material(HTM)-free PSC based on methyl ammonium tin triiodide(CH_(3) NH_(3) SnI_(3))was performed using a one-dimensional solar cell capacitance simulator(SCAPS-1D)*** eff ect of perovskite thickness,interface defect density,temperature,and electron transport material(ETM)on the photovoltaic performance of the device was *** to optimization,the device demonstrated a power conversion effi ciency(PCE)of 8.35%,fi ll factor(FF)of 51.93%,short-circuit current density(J_(sc))of 26.36 mA/cm 2,and open circuit voltage(V_(oc))of 0.610 *** the above parameters individually while keeping others constant,the obtained optimal absorber thickness was 1.0μm,the interface defect density was 1010 cm-2,the temperature was 290 K,and the TiO 2 thickness was 0.01μ*** simulating with the optimized data,the fi nal device gave a PCE of 11.03%,FF of 50.78%,J_(sc) of 29.93 mA/cm 2,and V_(oc) of 0.726 *** the optimized and unoptimized metric parameters,an improvement of~32.10%in PCE,~13.41%in J_(sc),and~19.02%in V_(oc) were ***,the results of this study are encouraging and can pave the path for developing highly effi cient PSCs that are cost-eff ective,eco-friendly,and comparable to state-of-the-art.

关键词： Perovskite solar cells Sn-based perovskite absorber TiO_(2) Defect density Temperature HTM-free

Pectin fractions extracted sequentially from Cerasus humilis:Their compositions,structures,functional properties and antioxidant activities

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Food Science and Human Wellness 2023年第2期12卷 564-574页

作者： Shikai Zhang Geoffrey INWaterhouse Tingting Cui Dongxiao Sun-Waterhouse Peng Wu College of Food Science and engineering Shandong Agricultural UniversityTaian 271018China School of Chemical Sciences The University of AucklandPrivate Bag 92019New Zealand Biology Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250103China

Three pectin fractions(water-soluble fraction(WSF),chelator-soluble fraction(CSF),and sodium carbonatesoluble fraction(NSF))were obtained from Chinese dwarf cherry(Cerasus humilis)*** of them were branched low methoxylated pectins with an amorphous or partially nanocrystalline nature and eight neutral monosaccharides(arabinose and galactose were most abundant).WSF,CSF and NSF had a degree of methylation(DM)of 35.82%,14.85%and 7.13%,uronic acid(UA)content of 76.02%,83.71%and 69.01%,and total protein content of 2.4%,2.1%and 8.8%,*** molecular weights were 340.31,330.16 and 141.31 kg/mol,respectively(analyzed by gel permeation chromatography(GPC)).WSF,CSF and NSF exhibited good rheological,thermal,emulsifying,emulsion-stabilizing,water-adsorbing,oil-binding,cholesterol-binding and antioxidant *** had the highest emulsifying,emulsion stabilizing,water-/oil-/cholesterol-binding and antioxidant capacities,followed by *** had the highest viscosity(406.77 m Pa·s),flowability,and resistance to heat-induced changes/damage,which may be related to its lowest polydispersity index,DM and UA content and highest protein *** three pectin fractions with desirable characteristics can be used as food additives/ingredients and dietary supplements.

关键词： Cerasus humilis fruits Pectin fractions Structural characteristics Processing-related functional properties

Residue behaviors and dietary risk of cyazofamid in turnip,onion and romaine lettuce assessed by a QuEChERS-LC-MS/MS methods

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Food Science and Human Wellness 2023年第5期12卷 1538-1544页

作者： Ruijuan Li Xue Men Rumei Li Tongjin Liu Hui Liang Feng Fang Dongxiao Sun-Waterhouse Yongli Wang Institute of Plant Protection Shandong Academy of Agricultural SciencesJinan 250100China College of Food Science and engineering Shandong Agricultural UniversityTaian 271018China School of Chemical Sciences The University of AucklandPrivate Bag 92019Auckland 1142New Zealand

In this study, the dissipation, terminal residues and dietary risk of the cyazofamid residue in three globally consumed minor crops, turnip(Brassica rapa L.), onion(Allium cepa L.)and romaine lettuce(Lactuca sativa L.)were assessed by supervised field trials at 6 locations of China in 2020. A reliable QuEChERS-LC-MS/MS method was developed for simultaneous analysis of cyazofamid and its primary metabolite, 4-chloro-5-p-tolylimidazole-2-carbonitrile(CCIM). The average recoveries of cyazofamid and CCIM in turnip, onion and romaine lettuce were 79%–97% and 77%–99%, respectively. The half-lives of cyazofamid in these crops were 5.7–6.5, 5.3–8.7 and 5.8–6.5 days in turnip, onion and romaine lettuce, respectively, with the final cyazofamid residues at harvest all lower than limit of quantitation(LOQ, 0.01 mg/kg). The turnip roots, onion bulbs and romaine lettuce leaves grown in China under Good Agricultural Practices conditions and harvested 10, 14 and 5 days, respectively, after the cyazofamid SC(100 g/L)application, would be reasonably safe for consumption by the general population. The maximum residue limit(MRL)values of cyazofamid could be tentatively set as 10 mg/kg for turnip leaves, 0.3 mg/kg for turnip roots, 0.05 mg/kg for onion bulbs, and 10 mg/kg for romaine lettuce leaves.

关键词： Cyazofamid residue Minor crops Maximum residue limit Dissipation Dietary risk assessment

Ultrafine Pt nanoparticles supported on double-shelled C/TiO2 hollow spheres material as highly efficient methanol oxidation catalysts

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Journal of Energy Chemistry 2020年第10期29卷 275-282页

作者： Xiaoyu Yue Yuguang Pu Wen Zhang Ting Zhang Wei Gao Department of Chemical and Materials engineering the University of AucklandPrivate Bag 92019Auckland 1142New Zealand

Catalyst support is extremely important for future fuel cell *** this work,we developed doubleshelled C/TiO2(DSCT)hollow spheres as an excellent catalyst support via a template-directed *** combination of hollow structure,TiO2 shell and carbon layer results in excellent electron conductivity,electrocatalytic activity,and chemical *** uniformed DSCT hollow spheres are used as catalyst support to synthesize Pt/DSCT hollow spheres *** resulting Pt/DSCT hollow spheres exhibited high catalytic performance with a current density of 462 mA mg^-1 for methanol oxidation reaction,which is 2.52 times higher than that of the commercial Pt/***,the increased tolerance to carbonaceous poisoning with a higher If/Ibratio and a better long-term stability in acid media suggests that the DSCT hollow sphere is a promising C/TiO2-based catalyst support for direct methanol fuel cells applications.

关键词： Catalyst support C/TiO2 hollow sphere Metal-support interactions Methanol oxidation reaction

Effects of Mechanical Milling and Sintering Temperature on the Densification, Microstructure and Tensile Properties of the Fe–Mn–Si Powder Compacts

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Journal of Materials Science & Technology 2016年第11期32卷 1161-1170页

作者： Zhigang Xu Michael A.Hodgson Peng Cao Department of Chemical and Materials engineering University of Auckland Private Bag 92019 Auckland 1142 New Zealand

This work reported on the effects of mechanical milling and sintering temperature on the densification,microstructure and mechanical properties of the Fe–28Mn–3Si（wt%） alloy. Elemental Fe, Mn and Si powders were used as the starting materials, and two batches of powder mixture were prepared： one was blended elemental（BE） powder mixture; the other was mechanically milled（MM） powder mixture milled for5 h using planetary ball milling. Both powder mixtures were pressed under a uniaxial pressure of 400 MPa,and subsequently sintered in a high vacuum furnace for 3 h at 1000, 1100, 1200 and 1300 °C. It was found that Mn depletion region（MDR） was formed on the surface of all the sintered samples. The sintered BE compacts had a low density（〈68.2%） at all temperatures, while the density of the sintered MM compacts increased drastically from ~65% at 1000 °C to ~91% at 1300 °C. All the sintered MM compacts were composed of a predominant γ-austenite and minor ε-martensite. In comparison, additional（Fe, Mn）3Si phase was observed in the BE alloys sintered at 1000 °C, and a single α-Fe phase was identified in the BE compact sintered at 1300 °C. The tensile properties of the sintered MM compacts increased significantly with the temperature and were significantly higher than those of their BE counterparts.

关键词： Fe–Mn–Si alloys Vacuum sintering Density Microstructure Tensile properties

Application of Machine Learning for Online Reputation Systems

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International Journal of Automation and computing 2021年第3期18卷 492-502页

作者： Ahmad Alqwadri Mohammad Azzeh Fadi Almasalha Department of Computer Science Applied Science Private UniversityAmman 11931Jordan Department of Software engineering Applied Science Private UniversityAmman 11931Jordan

Users on the Internet usually require venues to provide better purchasing *** can be provided by a reputation system that processes ratings to provide *** rating aggregation process is a main part of reputation systems to produce global opinions about the product *** methods that are frequently used do not consider consumer profiles in their calculations and cannot discover unfair ratings and trends emerging in new *** sophisticated rating aggregation methods that use a weighted average technique focus on one or a few aspects of consumers′profile *** paper proposes a new reputation system using machine learning to predict reliability of consumers from their *** particular,we construct a new consumer profile dataset by extracting a set of factors that have a great impact on consumer reliability,which serve as an input to machine learning *** predicted weight is then integrated with a weighted average method to compute product reputation *** proposed model has been evaluated over three Movie Lens benchmarking datasets,using 10-folds cross ***,the performance of the proposed model has been compared to previous published rating aggregation *** obtained results were promising which suggest that the proposed approach could be a potential solution for reputation *** results of the comparison demonstrated the accuracy of our ***,the proposed approach can be integrated with online recommendation systems to provide better purchasing recommendations and facilitate user experience on online shopping markets.

关键词： Reputation system rating aggregation machine learning consumer reliability user trust

Research e-infrastructures for open science: The national example of CSTCloud in China

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Data Intelligence 2023年第2期5卷 355-369页

作者： Lili Zhang Jianhui Li Paul F.Uhlir Liangming Wen Kaichao Wu Ze Luo Yude Liu Computer Network Information Center Chinese Academy of Sciences100190China consultant Information Policy and ManagementCallicoonNY12723USA

This paper focuses on research e-infrastructures in the open science *** analyze some of the challenges and opportunities of cloud-based science and introduce an example of a national solution in the China Science and Technology Cloud(CSTCloud).We selected three CSTCloud use cases in deploying open science modules,including scalable engineering in astronomical data management,integrated Earth-science resources for SDG-13 decision making,and the coupling of citizen science and artificial intelligence(AI)techniques in *** conclude with a forecast on the future development of research e-infrastructures and introduce the idea of the Global Open Science Cloud(GOSC).We hope this analysis can provide some insights into the future development of research e-infrastructures in support of open science.

关键词： Open science Open science cloud Research e-infrastructure Open science infrastructures Global Open Science Cloud Initiative