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Application of Crown-Flatness Vector Analysis in Plate Rolling Schedule

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Journal of Iron and Steel Research International 2004年第5期11卷 22-26页

作者： HU Xian-lei WANG zhao-dong JIAO Zhi-jie zhao zhong LIU Xiang-hua WANG Guo-dong Northeastern University

A simple plate crown model was introduced,and the crown-flatness vector analysis method was *** on the plate rolling technology,the rolling schedule design of elongation phase is divided into three *** step is to calculate the reductions of first pass of elongation making full use of the mill capability to decrease the total pass *** second step is to calculate the pass reduction for the last three or four passes to control crown and flatness by crown-flatness vector analysis *** the third step,the maximum rolling force limit and the total pass number are adjusted to make the plate gauge at exit equal to target gauge with satisfactory *** on-line application shows that this method is effective.

关键词： crown flatness,plate rolling schedule steepness

CaY-zeolite Catalyzed Etherification and Alkylation of Substituted Benzyl Alcohols

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Chinese Chemical Letters 2006年第1期17卷 15-18页

作者： Wei YU Miao WEN Guang Yu zhao Li YANG zhong Li LIU National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

The reaction of p- and/ α-subtituted benzyl alcohols in CaY-zeolite produced the corresponding dibenzyl ethers and/or benzyl toluenes as the principal products.

关键词： Benzyl alcohols CaY-zeolite etherification alkylation.

AMORPHOUS PHASE FORMATION OF Mo_(1-x)Ge_(x),Mo_(1-x)Si_(x),FILMS AND THEIR SUPERCONDUCTING PROPERTIES

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Chinese Physics Letters 1984年第1期1卷 23-26页

作者： zhao zhong-xian MENG Ru-ling ZHOU Ping LI Lin The Institute of Physics Academia Sinica

Mo_(1-x)Ge_(x),Mo_(1-x)Si_(x),films were prepared by getter sputtering onto liquid nitrogen cooled *** amorphous phase formations were Ge>22 at.%,Si>18 at.%*** the increase of Ge,Si content,Tc decreased from 6 to 3K in the amorphous *** measured results of(dBc2/dT)T_(c),Jc andρ(300K)/ρ(8K)indicated that the four chosen Mo_(1-x)Si_(x)films exhibit fundamental characteristics of amorphous superconductors.

关键词： amorphous (x)

Study on typical hole defects in AZ91D magnesium alloy prepared by low pressure lost foam casting

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China Foundry 2013年第4期10卷 232-236页

作者： Li Jiqiang zhao zhong Fan Zitian Dong Xuanpu Shi Hualiang School of Mechanical and Energy Ningbo Institute of TechnologyZhejiang University Ningbo University of Technology State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science and Technology

The hole defects can easily occur in magnesium alloy castings that are prepared by low pressure lost foam casting(LP-LFC)process when the process parameters such as vacuum,pouring temperature and f illing velocity are not properly *** this study,the forming mechanism of the hole defects in AZ91D magnesium castings by LP-LFC process was *** shape,location and surface appearance of the hole defects were observed using optical microscopy and scanning electron microscopy,and the chemical composition on the surface of the holes was analyzed using energy *** result indicates that there are two types of hole defects,i.e.,the pyrolysis products related hole defects,including concentrative hole and blow hole defects,and slag related hole *** concentrative hole and the blow-hole defects were formed either by the liquidEPS degradation products entrapped in the molten metal under the condition that the pouring temperature is equal to or lower than 730℃,or by the hindered transport of EPS pyrolysis *** irregular shape hole defects were caused by slag or by coating slough entrapment when the pouring temperature is equal to 750℃and the f illing velocity is equal to or greater than 100 mm·*** reduce or eliminate the hole defects,the vacuum and f illing velocity must be properly chosen to ensure that the metal front prof ile exhibits convex shape and in laminar current state,and the pouring temperature should be just high enough to ensure that the molten melt has adequate heat energy to complete the foam pyrolysis and to fully occupy the *** AZ91D magnesium castings in this study,the parameters should be 730℃pouring temperature,0.02-0.03 MPa vacuum and 80mm·s-1f illing velocity.

关键词： magnesium alloy low-pressure lost foam casting hole defects

Numerical and experimental studies on solidification of AZ80 magnesium alloy under out-of-phase pulsed magnetic field

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Journal of Magnesium and Alloys 2021年第1期9卷 166-182页

作者： Wenchao Duan Siqi Yin Wenhong Liu zhong zhao Kun Hu Ping Wang Jianzhong Cui Zhiqiang Zhang Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819LiaoningPR China College of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningPR China College of Information Science and Engineering Northeastern UniversityShenyang 110819LiaoningPR China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningPR China

For obtaining the finer grains of magnesium alloy,a novel combined pulsed magnetic field with different initial phases,also called out-ofphase pulsed magnetic field(OPPMF),was applied to study the solidification structure of AZ80 magnesium *** numerical simulation was simultaneously conducted to investigate the refinement *** experimental results showed that the macrostructure could be effectively refined by applying external magnetic ***,finer grains were obtained with the higher current ***,the increase of current intensity could only refine the grains to about 0.5 ***,compared to a single pulsed magnetic field(PMF)and alternating series of OPPMF(Connection II),a finer structure was observed when the consecutive series of OPPMF(Connection I)was *** contrast with a single PMF and Connection II,the numerical results showed that the greater axial Lorentz force was obtained under the Connection I,generating the stronger forced flow in the *** is believed that abundant nuclei could detach from the mold wall and move faster into the interior melt due to the stronger forced flow;besides,the lower superheat and greater temperature uniformity in bulk melt were realized,accounting for the finest structures under the Connection I.

关键词： Out-of-phase pulsed magnetic field Magnesium alloy Grain refinement Numerical simulation Forced flow

THREE-DIMENSIONAL REGULARITIES OF DISTRIBUTION OF AIR-INLET CHARACTERISTIC VELOCITY IN NATURAL-DRAFT WET COOLING TOWER

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Journal of Hydrodynamics 2008年第3期20卷 323-330页

作者： WANG Kai SUN Feng-zhong zhao Yuan-bin GAO Ming SHI Yue-tao School of Energy and Power Engineering Shandong University Jinan 250061 China

A model for heat and mass transfer in a natural-draft wet cooling tower was established. Numerical simulation with the κ-ε turbulent model was conducted. Distribution rules of air inlet aerodynamic field were studied. Field experiments were done in a cooling tower in power plant, and the test data was compared with the related results. The definition of characteristic air velocity was proposed and its influencing factors, such as the cross-wind velocity and circumferential angle, were quantitatively studied. It can be used to evaluate the performance of cooling tower and to calculate the ventilation quantity and resistance of air inlet. It is also a theoretical basis for cooling tower design and performance optimization.

关键词： cooling tower flow field numerical simulation air inlet

The decomposition rates of dead plant materials of two species of Spartina and the changes in their nutritive components

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Acta Oceanologica Sinica 1988年第1期7卷 119-125页

作者： Jiang Fuxing, Wang Weizhong, zhao Ming and zhong Chongxin China

-The detritus from the decomposition of dead plant materials of Spartina with great biomass provides abundant food for the heterotrophs in estuarine and nearshore coastal waters. It is for this reason that the decomposition rates of S. anglica and S. alterniflora near the estuary of obsolete Huanghe River were studied. The changes in nutritive components during decomposition are also *** showed that the decomposition rate of dead leaves of S. anglica on ultra-low marsh was about 90% for the first year. In the eighth month, it was 80% and 76 % respectively for S. anglica and S. alterniflora on low marsh. Protein content of the two species of Spartina increased in the course of decomposition, with a maximum increment of 100% or more. The energy value also increased, whereas cellulose content decreased markedly. The percentage content of ash and lipid varied significantly with zonal differences.

关键词： rate The decomposition rates of dead plant materials of two species of Spartina and the changes in their nutritive components

Research and application of the angular rolling technology for plate mill

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Advances in Manufacturing 2023年第3期11卷 462-476页

作者： Zhi-Jie Jiao Jun-Yi Luo Zhi-Qiang Wang Zhi-Peng Xu Chun-Yu He zhong zhao State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819People's Republic of China

Angular rolling technology can overcome the size limitation of plate mill equipment and product heavy steel plate with large unit weight or improve the production efficiency of small width spreading ratio *** the DEFORM software,the numerical simulation study of the angular rolling process was carried out,and the relation laws of the width,rolling force and strain of the rolled piece under different angular rolling process conditions were *** simulation results show that with the rotation angle increasing,the width of the rolled piece *** with the conventional rolling process,the rolling force changes gradually during the biting and throwing stage of the angular rolling *** the rotation angle increasing,both the equivalent strains in the thickness direction and in the width direction gradually *** to the pattern and dimension's changing formula in the double-pass angular rolling process,the prediction model of angle,reduction and width spreading is *** opening value of side guide is set for the rotation angle *** one 5000 mm heavy plate mill,the automation control system was modified,and the angular rolling technology was applied *** absolute deviation of target width does not exceed±20 mm and the relative deviation does not exceed 1%.The large unit weight plate that cannot be rolled with traditional process,can be produced now,and the annual output increases by 10000 t.

关键词： Plate mill Angular rolling Numerical simulation Width spreading Prediction model Online application

Wide-range tracking technique for process-variation-robust clock and data recovery applications

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 729-737页

作者： Jun-sheng LV You LI Yu-mei ZHOU Jian-zhong zhao Hai-hua SHEN Feng ZHANG Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China

A wide-range tracking technique for clock and data recovery(CDR) circuit is presented. Compared to the traditional technique, a digital CDR controller with calibration is adopted to extend the tracking range. Because of the use of digital circuits in the design, CDR is not sensitive to process and power supply variations. To verify the technique, the whole CDR circuit is implemented using 65-nm CMOS technology. Measurements show that the tracking range of CDR is greater than ±6×10-3 at 5 Gb/s. The receiver has good jitter tolerance performance and achieves a bit error rate of <10–12. The re-timed and re-multiplexed serial data has a root-mean-square jitter of 6.7 ps.

关键词： Clock and data recovery Digital loop filter Phase interpolator