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Facile synthesis of monodispersed copper oxalate flaky particles in the presence of EDTA

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International Journal of Minerals,Metallurgy and Materials 2018年第7期25卷 762-769页

作者： xing Chert Kai huang Cheng-yan Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Lab of Green Recycling and Extraction of Metals University of Science and Technology BeijingBeijing 100083China

Monodispersed copper oxalate paxticles with flaky morphology were prepared via a simple one-pot synthesis method. Scanning electron microscope （SEM）, X-ray diffraction （XRD）, and fourier tza^sform infraJced （FTIR） spectra were used to characterize paxticle mor- phology, size, phase composition, and functional groups. It was found that the presence of ethylenediaminetetzaacetic acid （EDTA） and the solution pH value had strong influence on the morphological and size evolution of the precipitated particles. On the basis of controlled re- lease of copper ions from a Cu2＋-EDTA complex and Weimazn＇s law, a stzategy for the controlled synthesis of monodispersed copper oxa- late paxticles was designed by refemng to the basic mode of the St0ber method. The inherent nature of crystallization to form the flaky solid in the early stage of precipitation as well as the driving force of the long-lasting low supersaturation in the growth stage was proposed to ex- plain the size and morphological evolution of the copper oxalate precipitates. Thermodynamic equilibrium concentrations of copper（II） spe- cies in the Cu（II）-EDTA-oxalate-H20 solution system were calculated to help explain the possible formation mechaNsm of copper oxalate precipitates.

关键词： copper oxalate flaky morphology ethylenediaminetetzaacetic acid one-pot synthesis

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文档级神经机器翻译综述

软件学报 2025年第1期36卷 152-183页

作者：吕星林李军辉陶仕敏杨浩张民苏州大学计算机科学与技术学院华为翻译中心

机器翻译(machine translation, MT)研究旨在构建一个自动转换系统,将给定源语言序列自动地转换为具有相同语义的目标语言序列.由于机器翻译广阔的应用场景,使其成为自然语言理解领域乃至人工智能领域的一个重要的研究方向.近年来,端到... 详细信息

机器翻译(machine translation, MT)研究旨在构建一个自动转换系统,将给定源语言序列自动地转换为具有相同语义的目标语言序列.由于机器翻译广阔的应用场景,使其成为自然语言理解领域乃至人工智能领域的一个重要的研究方向.近年来,端到端的神经机器翻译(neural machine translation, NMT)方法显著超越了统计机器翻译(statistical machine translation, SMT)方法,成为目前机器翻译研究的主流方法.然而,神经机器翻译系统通常以句子为翻译单位,在面向文档的翻译场景中,将文档中每个句子独立地进行翻译,会因脱离文档的篇章语境引起一些篇章级的错误,如词语错翻、句子间不连贯等.因此将文档级的信息融入到翻译的过程中去解决跨句的篇章级错误是更加自然和合理的做法,文档级的神经机器翻译(document-level neural machine translation, DNMT)的目标正是如此,成为机器翻译研究的热门方向.调研了近年来在文档级神经机器翻译研究方向的主要工作,从篇章评测方法、使用的数据集和模型方法等方面系统地对当前研究工作进行了归纳与阐述,目的是帮助研究者们快速了解文档级神经机器翻译研究现状以及未来的发展和研究方向.同时在文中也阐述了在文档级神经机器翻译的一些展望、困难和挑战,希望能带给研究者们一些启发.

关键词：神经机器翻译 Transformer模型文档上下文篇章评测

An experimental study on the impact behavior of cavitation inside tip clearance of a hydrofoil

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Journal of Hydrodynamics 2023年第6期35卷 1208-1214页

作者： Yan-tao Cao Liang-hao Xu Xiao-xing Peng National Key Laboratory on Ship Vibration and Noise China Ship Scientific Research CenterWuxi214082China Taihu Laboratory of Deepsea Technological Science Wuxi214082China

Tip clearance cavitation is one of the most common cavitation phenomena exist on duct propellers,pumps and some hydraulic turbines,which may lead to erosion of the *** to the influence of the nearby wall,cavitation inside the tip clearance is more complicated than other cases without *** far,the understanding about the impact mechanism of tip clearance cavitation is still *** this paper,to obtain the impact behavior of tip clearance cavitation,a high-speed camera was used to capture the cavitation behavior inside the tip clearance of a hydrofoil,and surface paint coating peeling method was applied to show the impact *** indicated that cavitation around the tip of the hydrofoil was composed of a tip separation cavity and a tip leakage vortex cavity,and the one with contribution to impact was the tip separation *** the comprehensive analysis of the paint peeling region and dynamic behavior of tip separation cavity,the impact was found to be related to the local collapse and rebound of the cloud cavitation shed from the attached *** addition,the influence of tip clearance size on the behavior of tip clearance cavitation was also *** the tip clearance size increased,the tip separation cavity tended to transfer from sheet cavitation to vortex *** findings can provide a sound basis for evaluating the erosion risk arising from the tip clearance cavitation.

关键词： Tip clearance cavitation impact region impact behavior tip clearance size

Procyanidin B2 protects against diet-induced obesity and non-alcoholic fatty liver disease via the modulation of the gut microbiota in rabbits

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World Journal of Gastroenterology 2019年第8期25卷 955-966页

作者： Ya-Wei xing Guang-tao Lei Qing-Hua Wu Yu Jiang Man-Xiang huang Department of Gastroenterology The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Department of Cardiovascular Medicine The Second Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Procyanidins have beneficial effects on metabolic syndrome and antimicrobial activity,but the mechanisms underlying these effects are *** To investigate the effects of procyanidin B2(PB2)on non-alcoholic fatty liver disease and to explore the possible *** Thirty male New Zealand white rabbits were randomized into three *** of them were fed either a high-fat-cholesterol diet(HCD)or chow ***-fed rabbits were treated with vehicle or PB2 daily for 12 *** weight and food intake were evaluated once a *** biomarkers,such as total cholesterols,triglycerides,and aspartate transaminase,were *** rabbits were sacrificed and histological parameters of liver were assessed by hematoxylin and eosin-stained ***,several lipogenic genes and gut microbiota(by 16S rRNA sequencing)were investigated to explore the possible *** The HCD group had higher body weight,liver index,serum lipid profile,insulin resistance,serum glucose,and hepatic steatosis compared to the CHOW ***2 treatment prevented HCD-induced increases in body weight and hypertriglyceridemia in association with triglyceride accumulation in the ***2 also ameliorated low-grade inflammation,which was reflected by serum lipopolysaccharides and improved insulin *** rabbit liver,PB2 prevented the upregulation of steroid response element binding protein 1c and fatty acid synthase and the downregulation of carnitine palmitoyltransferase,compared to the HCD ***,HCD led to a decrease of Bacteroidetes in gut ***2 significantly improved the proportions of Bacteroidetes at the phylum level and Akkermansia at the genus *** Our results indicate the possible mechanism of PB2 to improve HCD-induced features of metabolic syndrome and provide a new dietary supplement.

关键词： Procyanidin Rabbit Non-alcoholic fatty liver disease Gut microbiota 16S rRNA

Optimization of reaction conditions for the electroleaching of manganese from low-grade pyrolusite

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1121-1130页

作者： xing-ran Zhang Zuo-hua Liu xing Fan Xin Lian Chang-yuan tao College of Chemistry and Chemical Engineering Chongqing University Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization

In the present study, a response surface methodology was used to optimize the electroleaching of Mn from low-grade pyrolusite. Ferrous sulfate heptahydrate was used in this reaction as a reducing agent in sulfuric acid solutions. The effect of six process variables, including the mass ratio of ferrous sulfate heptahydrate to pyrolusite, mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio, current density, leaching temperature, and leaching time, as well as their binary interactions, were modeled. The results revealed that the order of these factors with respect to their effects on the leaching efficiency were mass ratio of ferrous sulfate heptahydrate to pyrolusite 〉 leaching time 〉 mass ratio of sulfuric acid to pyrolusite 〉 liquid-to-solid ratio 〉 leaching temperature 〉 current density. The optimum conditions were as follows： 1.10：1 mass ratio of ferrous sulfate heptahydrate to pyrolusite, 0.9：1 mass ratio of sulfuric acid to pyrolusite, liquid-to-solid ratio of 0.7：1, current density of 947 A/m^2, leaching time of 180 min, and leaching temperature of 73°C. Under these conditions, the predicted leaching efficiency for Mn was 94.1%; the obtained experimental result was 95.7%, which confirmed the validity of the model.

关键词： pyrolusite manganese ore treatment electroleaching reaction conditions optimization

Carbon dioxide reforming of methane over Ni/Mo/SBA-15-La_2O_3 catalyst:Its characterization and catalytic performance

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Journal of Natural Gas Chemistry 2011年第5期20卷 465-470页

作者： Jian huang Renxiong Ma tao huang Anrong Zhang Wei huang Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 Shanxi China Institute of Engineering Thermophysics ＆ Chinese Academy of Sciences Beijing 100190 China Department of Applied Chemistry Yuncheng University Yuncheng 044000 Shanxi China

The Ni/Mo/SBA-15 catalyst was modified by La2O3 in order to improve its thermal stability and carbon deposition resistance during the CO2 reforming of methane to syngas. The catalytic performance, thermal stability, structure, dispersion of nickel and carbon deposition of the modified and unmodified catalysts were comparatively investigated by many characterization techniques such as N2 adsorption, H2-TPR, CO2-TPD, XRD, FT-IR and SEM. It was found that the major role of La2O3 additive was to improve the pore structure and inhibit carbon deposition on the catalyst surface. The La2O3 modified Ni/Mo/SBA-15 catalyst possessed a mesoporous structure and high surface area. The high surface area of the La2O3 modified catalysts resulted in strong interaction between Ni and Mo-La, which improved the dispersion of Ni, and retarded the sintering of Ni during the CO2 reforming process. The reaction evaluation results also showed that the La2O3 modified Ni/Mo/SBA-15 catalysts exhibited high stability.

关键词： CO2-reforming SBA-15 molecular sieve carbon deposition La-promoted

Convergence to the Rarefaction Wave for a Model of Radiating Gas in One-dimension

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 239-256页

作者： Fei-min huang xing LI Academy Mathematics and Systems Science the Chinese Academy of Sciences College of Mathematics and Statistics Shenzhen University

In this paper, a sequence of solutions to the one-dimensional motion of a radiating gas are con- structed. Furthermore, when the absorption coefficient a tends to oo, the above solutions converge to the rarefaction wa... 详细信息

关键词： rarefaction wave compressible euler system radiating gas, hyperbolic-elliptic system

An output-based distributed observer and its application to the cooperative linear output regulation problem

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Control Theory and Technology 2019年第1期17卷 62-72页

作者： tao LIU Jie huang Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Shatin N.T. Hong Kong China

In this paper, we first extend an existing stability result for a class of linear switched systems. This extended result will relax the existenceconditions of the output-based distributed observer for a leader system subject to jointly connected switching communication networks in the literature. As an application of this output-based distributed observer, we solve the cooperative output regulati on problem of a linear multi-age nt system subject to jointly connected switching communicatio n n etworks by composing a purely decentralized control law and the output-based distributed observer based on the certainty equivalence principle.

关键词： Output-based distributed observer switched systems cooperative output regulation

A micro-spectrometer with phase modulation array

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Frontiers of Optoelectronics 2014年第1期7卷 59-63页

作者： tao YANG Yuchao CHEN xing'ao LI Wei huang Yongyuan ZHU Key Laboratory for Organic Electronics & Information Displays Nanjing University of Posts and Telecommunications Nanjing 210023 China National Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China

A micro-spectrometer with phase modulation array is investigated in this paper. The vital component of this micro-spectrometer is a micro-interferometer array, which is built on a charge-coupled device （CCD） or a complementary metal oxide semiconductor （CMOS）. Each element of micro-interferometer array is formed by polymethyl methacrylate （PMMA） grooves with different depth. When we illuminate the surface of the interferom- eter array, different interference intensity distribution would be formed at the bottom of each micro-interferom- eter. Optical power of this by the pixels of CCD substituted into a linear interferometer can be measured or CMOS. The data can be system. By solving the linear system with Tikhonov regularization method, spectrum of the incident beam can be reconstructed. Simulation results prove that the detection range of the spectrometer is a wide wavelength range covering from 300 to 1100 nm. Furthermore, the wavelength resolution of the device reaches picometer level. In comparison with conventional spectrometers, the novel spectrometer has distinct advan- tages of small size, low cost, high resolution, wide spectral measurement range, real-time measurement, and so on.

关键词： micro-spectrometer spectrum reconstruction,Tikhonov regularization