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research on mine dustfall agents based on the mechanism of wetting and coagulation

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 205-209页

作者： Jing Yang Dan-dan Liu Bing-jie Liu Min-min He Ying-feng Wang College of Chemical and Environmental Engineering Shandong University of Science and Technology Key laboratories of Coal Mine Disaster Prevention and Control Shandong University of Science and Technology

Mine dust is classified as one of five natural coal mining disasters because it can harm the health of miners and poses a serious threat to the safety of the coal mine. Therefore, preparation of an effective dust suppression agent is highly desired. To improve the capture efficiency of fine dust, this study examines the dust suppression effects of various combinations of wetting agents, additives, and coagulation agents by using the optimum seeking method to reduce mine dust, particularly respirable particles. The optimal formula is shown to contain 10wt% fatty alcohol polyoxyethylene ether（JFC）, 4.96wt% cationic polyacrylamide, and 4wt% calcium chloride. The dust suppression effect can be achieved at 96.1% in 5 min by using the optimal formula.

关键词： mine dust dust abatement wetting coagulation surface tension contact angle

Development of highly active coated monolith SCR catalyst with strong abrasion resistance for low-temperature application

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Frontiers of Environmental Science & Engineering 2015年第6期9卷 979-987页

作者： Lina GAN Shan LEI Jian YU Hongtao MA Yo YAMAMOTO Yoshizo SUZUKI Guangwen XU Zhanguo ZHANG State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Materials research Department Materials Research Laboratories Research and Development Group Meidensha Corporation 8-1 Osaki 2-Chome Shinagawa-ku Tokyo 141-8565 Japan National Institute of advanced Industrial Science and technology (AIST) Onogawa 16-1 Tsukuba 305-8569 Japan

Monolith SCR catalysts coated with V2Os- WO3/TiO2 were prepared by varying binder and coating thickness. Comparing with a monolith extruded with 100% V2O5-WO3/TiO2 powder, a coated monolith with a catalyst-coating layer of 260 μm in thickness exhibited the similar initial NOx reduction activity at 250℃. After 4 h abrasion （attrition） in an air stream containing 300 g. m^-3 fine sands （50-100μm） at a superficial gas velocity of 10m·s^-1, the catalyst still has the activity as a 100% molded monolith does in a 24-h activity test and it retains about 92% of its initial activity at 250℃. Estimation of the equivalent durable hours at a fly ash concentration of 1.0 g.m^-3 in flue gas and a gas velocity of 5 m.s^-1 demonstrated that this coated monolith catalyst is capable of resisting abrasion for 13 months without losing more than 8% of its initial activity. The result suggests the great potential of the coated monolith for application to de-NOx of flue gases with low fly ash concentrations from, such as glass and ceramics manufacturing processes.

关键词： coated monolith low-temperature denitration,abrasion resistance attrition

Impact of uneven distribution of grain characteristics on yield strength and martensitic transformation of as-hot-rolled medium-entropy alloys

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Journal of Materials Science & technology 2024年第10期177卷 234-245页

作者： Jungwan Lee Hyojin Park Sujung Son Jae Wung Bae Jin You Kim Sung Kyu Kim Jae-il Jang Hyoung Seop Kim Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Department of Metallurgical Engineering Pukyong National UniversityBusan 48513Republic of Korea Technical research laboratories Energy and Shipbuilding Steel Research GroupPOSCOPohangRepublic of Korea Division of Materials Science and Engineering Hanyang UniversitySeoul 04763Republic of Korea Graduate Institute of Ferrous&Eco Materials technology(GIFT) Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Center for Heterogenic Metal Additive Manufacturing Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea advanced Institute for Materials research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan

As-hot-rolled medium-entropy alloys(MEAs)with unevenly distributed grain sizes of face-centered cubic grains exhibit better yield strength without uniform elongation loss compared to cold-rolled and an-nealed *** operation of dynamic recrystallization(DRX)during several hot rolling passes leads to a wide range of grain sizes from submicrons to tens of micrometers due to the grain growth after nucleation:early recrystallized grains are coarser than recently recrystallized *** only the grain size but internal dislocation density of the recently recrystallized grain is *** the tensile deformation of the hot-rolled MEAs at-196 ℃,dislocation pile-ups in the relatively soft and fine DRX grains enhance yield stress and hetero-deformation-induced strain *** to the enhanced yield stress of the as-hot-rolled MEAs,stress-induced martensitic transformation easily ***,partially DRXed MEAs hot-rolled at 800 ℃ have lower yield stress than fully DRXed ones,hot-rolled at 900 and 1000 ℃.This is attributed to the softening effect of the stress-induced body-centered cubic martensitic transformation in unrecrystallized coarse grains prior to the yielding,which lowers the yield stress of the partially DRXed *** yielding,the martensitic transformation facilitates strain hard-ening and early necking is *** study presents a fresh outlook on the uneven distribution of grain sizes by hot rolling beneficial to mechanical responses of uniform elongation of~45%despite the as-rolled states with an advantage of simplified thermo-mechanical processes.

关键词： Dynamic recrystallization Nucleation and growth Heterogeneity Grain size distribution Deformation-induced martensitic transformation

Influences of tool plunge speed and tool plunge depth on friction spot joining of AA5454-O aluminum alloy plates with different thicknesses

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中国有色金属学会会刊：英文版 2012年第S3期22卷 629-633页

作者： Sung-Ook YOON Myoung-Soo KANG Yong-Jai KWON Sung-Tae HONG Dong-Hwan PARK Kwang-Hak LEE Chang-Yong LIM Jong-Dock SEO School of Materials Science and Engineering University of Ulsan School of Mechanical Engineering University of Ulsan Institute of E-Vehicle technology University of Ulsan Technical research laboratories Shin Young Co.Ltd.

AA5454-O aluminum alloy plates with the thicknesses of 1.4 and 1.0 mm were friction-spot-joined (FSJed).The plunge speed of the joining tool was changed in a range of 100 500 mm/min under a constant rotation speed of 500 r/*** plunge depth was ranged from 1.6 mm to 2.2 *** tool plunge speed did not make a remarkable effect on the surface appearance and macro-structure of the FSJed *** average hardness of the FSJed zone was greater than or equal to that of the base ***,there was no remarkable tendency in the average hardness change of the FSJed zone in spite of the variation in the tool plunge speed and tool plunge *** increase of the tool plunge depth resulted in the increase of the tensile shear ***,the change of the tool plunge speed did not lead to the remarkable variation in the tensile shear load of the FSJed *** was noteworthy that the FSJed plate exhibited the highest tensile shear load of about 4.0 kN.

关键词： friction spot joining AA5454-O aluminum alloy plunge speed plunge depth mechanical property

Analysis of rolls deflection of Sendzimir mill by 3D FEM

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中国有色金属学会会刊：英文版 2007年第3期17卷 600-605页

作者：喻海良刘相华 LEE Gyoo Taek State Key Laboratory of Rolling and Automation Northeastern University POSCO Technical research laboratories Pohang 790-785 Korea

The deflection of rolls of Sendzimir mill with double AS-U-Roll was simulated by finite element method(FEM). The influences of rolling pressure, strip width and rolls-assignment on rolls deflection were analyzed. The results show that the work roll deflection increases with the increase of rolling pressure and the reduction of work roll radius, but the rigid displacement of work roll slightly changes; the work roll end might appear negative displacement for the narrow strip width and high rolling pressure that might cause the contact of work rolls. The research results are significant for guiding production and theoretical analysis of the rolls system of Sendzimir mill.

关键词：滚转偏度磨粉机有限元件 3D技术

Synthesis,Crystal Structure and Spectroscopic Properties of 1,2-Benzothiazine Derivatives:An Experimental and DFT Study

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Chinese Journal of Structural Chemistry 2015年第1期34卷 15-25页

作者： MUHAMMAD Nadeem Arshad TARIQ Mahmood ATHER Faroque Khan MUHAMMAD Zia-Ur-Rehman ABDULLAH M.Asiri ISLAM Ullah Khan RIFFAT-Un-Nisa KHURSHID Ayub AZAM Mukhtar MUHAMMAD Tariq Saeed Chemistry Department Faculty of ScienceKing Abdulaziz University Centre of Excellence for advanced Materials research (CEAMR) King Abdulaziz University Department of Chemistry COMSATS Institute of Information TechnologyAbbottabad IRCBM COMSATS Institute of Information Technology Applied Chemistry research Center PCSIR Laboratories ComplexFerozpur RoadLahore 54600Pakistan Materials Chemistry Laboratory Department of ChemistryGC University Department of Chemistry College of ScienceKing Faisal University Department of Chemistry University of EducationOkara CampusOkara-Pakistan

1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.

关键词： 1,2-benzothiazine B3LYP/6-31+G (d) density functional theory (DFT) HUMO-LUMO crystal structures

Antidiabetic and antidiarrhoeal effects on ethanolic extract of Psidium guajava(L.) *** in Wister rats

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Asian Pacific Journal of Tropical Biomedicine 2015年第1期5卷 10-14页

作者： Santosh Mazumdar Rashcda Akter Debashish Talukder Pharmacology research division Bangladesh Council of Scientific and Industrial Research Laboratories Chittagong Applied Zoology research Division Bangladesh Council of Scientific and Industrial Research Laboratories Rajshahi

Objective:To evaluate the antidiabetic and the antidiarrhoeal effects of ethanolic extracts of Psidium guajava leave(EEPGL) in Wisier rais to support its traditional ***:Oral glucose tolerance test model and alloxan induced diabetic test model were performed to evaluate antidiabetic activity of EEPGL at doses of 1.***.0.50 and 0.75 g/kg *** antidiarrhoeal effects of *** oil-induced diarrhoea model and gastrointestinal motility test with barium sulphate milk model were also assessed at doses of750.500 and 250 mg/***:Administration of EEPGL at doses 1.00 and 0.50 g/kg significantly(P<0.05)decreased blood glucose levels in oral glucose tolerance test model as well as 0.75 g/kg dose in alloxan induced diabetic test model in Wister rats(P<0.001).Application of EEPGL at doses of 750 and 500 mg/kg showed antidiarrhoeal effect in castor oil-induced diarrhoeal model(P<0.00 l and P<0.01,respectively),and 750 mg/kg(P<0.01),500 and 250 mg/kg(P<0.05)doses in barium sulphate milk model in aforesaid ***:These results exhibited the significant antidiabetic and antidiarrhoeal activities of ethanolic extracts of Psidium guajava leave in Wister rats.

关键词： Psidium guajava Leave extract Antidiabetic Antidiarrhoea Wister rats

A 24−30 GHz 8-element dual-polarized 5G FR2 phased-array transceiver IC with 20.8-dBm TX OP1dB and 4.1-dB RX NF in 65-nm CMOS

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Journal of Semiconductors 2024年第1期45卷 22-32页

作者： Yongran Yi Dixian Zhao Jiajun Zhang Peng Gu Chenyu Xu Yuan Chai Huiqi Liu Xiaohu You National Mobile Communication research Laboratory Southeast UniversityNanjing 211189China Purple Mountain laboratories Nanjing 211111China Chengdu Xphased technology Company Ltd. Chengdu 610041China

This article presents an 8-element dual-polarized phased-array transceiver(TRX)front-end IC for millimeter-wave(mm-Wave)5G new radio(NR).Power enhancement technologies for power amplifiers(PA)in mm-Wave 5G phased-array TRX are discussed.A four-stage wideband high-power class-AB PA with distributed-active-transformer(DAT)power combining and multi-stage second-harmonic traps is proposed,ensuring the mitigated amplitude-to-phase(AM-PM)distortions across wide carrier frequencies without degrading transmitting(TX)power,gain and *** and receiving(RX)switching is achieved by a matching network co-designed on-chip T/R *** each TRX element,6-bit 360°phase shifting and 6-bit 31.5-dB gain tuning are respectively achieved by the digital-controlled vector-modulated phase shifter(VMPS)and differential attenuator(ATT).Fabricated in 65-nm bulk complementary metal oxide semiconductor(CMOS),the proposed TRX demonstrates the measured peak TX/RX gains of 25.5/21.3 dB,covering the 24−29.5 GHz *** measured peak TX OP1dB and power-added efficiency(PAE)are 20.8 dBm and 21.1%,*** measured minimum RX NF is 4.1 *** TRX achieves an output power of 11.0−12.4 dBm and error vector magnitude(EVM)of 5%with 400-MHz 5G NR FR2 OFDM 64-QAM signals across 24−29.5 GHz,covering 3GPP 5G NR FR2 operating bands of n257,n258,and n261.

关键词： fifth-generation(5G) power amplifier millimeter-wave transceiver phased-array

NICT/ATR Chinese-Japanese-English Speech-to-Speech Translation System

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Tsinghua Science and technology 2008年第4期13卷 540-544页

作者： Tohru Shimizu Yutaka Ashikari Eiichiro Sumita 张劲松 Satoshi Nakamura Knowledge Creating Communication research Center National Institute of Information and Communications Technology ATR Spoken Language Translation Research Laboratories 2-2-2 Keihanna Science City Kyoto 619-0288 Japan

This paper describes the latest version of the Chinese-Japanese-English handheld speech-tospeech translation system developed by NICT/ATR, which is now ready to be deployed for travelers. With the entire speech-to-speech translation function being implemented into one terminal, it realizes real-time, location-free speech-to-speech translation. A new noise-suppression technique notably improves the speech recognition performance. Corpus-based approaches of speech recognition, machine translation, and speech synthesis enable coverage of a wide variety of topics and portability to other languages. Test results show that the character accuracy of speech recognition is 82%-94% for Chinese speech, with a bilingual evaluation understudy score of machine translation is 0.55-0.74 for Chinese-Japanese and Chinese-English

关键词： speech-to-speech translation speech recognition speech synthesis machine translation large-scale corpus