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A NEURAL NETWORK FOR WELD PENETRATION CONTROL IN GAS TUNGSTEN ARC WELDING

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 27-33页

作者： C.S. Wu J. Q. Gao Y.h. zhao Institute of Materials Joining Shandong University Jinan 250061 China

Realizing of weld penetration control in gas tungsten arc welding requires establishment of a model describing the relationship between the front-side geometrical parameters of weld pool and the back-side weld width with sufficient accuracy. A neural network model is developed to attain this aim. Welding experiments are conducted to obtain the training data set （including 973 groups of geometrical parameters of the weld pool and back-side weld width） and the verifying data set （108 groups）. Two data sets are used for training and verifying the neural network, respectively. The testing results show that the model has sufficient accuracy and can meet the requirements of weld penetration control.

关键词： neural network weld penetration control back-side weld width,gas tungsten arc welding

Enantioselective hydrolysis of naproxen ethyl ester catalyzed by polyclonal antibodies

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Chinese Science Bulletin 1997年第9期42卷 741-744页

作者： hu, YJ Yang, Bh zhao, h Wu, YL Ji, YY Ye, M State Key Laboratory of Bicorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai China

BASED on the hypothesis of Pauling on enzyme action that free energy difference between theground and transition state is reduced by the specific binding of active center of enzyme to theintermediate,a large number of... 详细信息

关键词： enantioselectivity hydrolysis of naproxen ethyl ester polyclonal antibody catalytic antibody.

ELECTROPOLYMERIZATION OF ANILINE ON ZINC-ELECTROPLATED STEEL FROM NEUTRAL AQUEOUS MEDIUM BY SINGLE-STEP PROCESS

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 849-855页

作者： Y.P.zhao R.h.Yin W.M.Cao A.B.Yuan Dept.ofChem. CollegeofScienceShanghaiUniv.Shanghai200436China

Polyaniline films were successfully synthesized on zinc-electroplated steel sheets in sodium salicylate (1mol·dm-3) aqueous medium. This one-step aniline electropolymerization process has been studied in this paper using different electrochemical techniques. And scanning electron microscopy (SEM) showed that the polymer coatings rapidly formed by either galvanostatic or potentiostatic mode performed compact and uniform in morphology. Potentiodynamic polarization was used to test the anticorrosion properties of this polymer.

关键词： anticorrosion electropolymerization polyaniline salicylate zinc

Coherent Acoustic Phonon and Its Chirping in Dirac Semimetal Cd_3As_2

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Chinese Physics Letters 2018年第11期35卷 56-60页

作者： Fei Sun M.Yang M W Yang Q.Wu h.zhao X.Ye Youguo Shi Jimin zhao Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049

Ultrafast optical spectroscopy of a single crystal of a Dirac semimetal Cd_3As_（2 ）is carried *** acoustic phonon（AP）mode with central frequency f=0.037 Thz（i.e.,1.23 cm^（-1）or 0.153 meV）is unambiguously generated and detected,which we attribute to laser-induced thermal *** AP chirping（i.e.,variation of the phonon frequency）is clearly detected,which is ascribed to heat capacity variation with *** comparing our experimental results and the theoretical model,we obtain a chirping time constant,which is 31.2 ps at 6 K and 19.8 ps at 300 K,***,we identify an asymmetry in the AP frequency domain peak and find that it is caused by the chirping,instead of a Fano ***,we experimentally demonstrate that the central frequency of AP is extremely stable with varying laser fluence,as well as temperature,which endows Cd_3As_2application potentials in thermoelectric devices.

关键词： As Cd AP Coherent Acoustic Phonon and Its Chirping in Dirac Semimetal Cd3As2

Reconstruction of Conceptual Prediction Model for the Three Rainfall Patterns in the summer of eastern China under global warming

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Science China Earth Sciences 2014年第4期57卷 3047-3061页

作者： zhao Junhu FENG GuoLin National Climate Center China Meteorological Administration College of Atmospheric Sciences Lanzhou University

With the influence of global warming,the global climate has undergone significant inter-decadal variation since the late *** El Nio-Southern Oscillation(ENSO)has been the strongest signal for predicting global climate inter-annual variability,its relation with the summer rainfall in China has significantly changed,and its indicative function on the summer rainfall in China has *** has led to a significant decrease in the accuracy rate of early conceptual prediction models for the Three Rainfall Patterns in the summer of eastern *** the basis of the difference analysis of atmospheric circulation system configuration in summer,as well as the interaction of ocean and atmospheric in previous winter between two phases,*** and after the significant global warming(1951 to 1978 and 1979 to 2012,respectively),we concluded that(1)Under different inter-decadal backgrounds,the atmospheric circulations that impacted the Three Rainfall Patterns in the summer of eastern China showed consistency,but in the latter phase of the global warming,the Western Pacific Subtropical high(WPSh)was on the strong side,the position of which was in the south,and the blocking high in the Eurasia mid-high latitudes was active,while the polar vortex extended to the south,and meridional circulation *** circulation background may have been conducive to the increase of the circulation frequency of Patterns II and III,and the decrease of the circulation frequency of Pattern I,thus leading to more Patterns II and III and fewer Pattern I in the summer rainfall of eastern China.(2)In the former phase,the corresponding previous winter SST fields of different rainfall patterns showed visible *** impact of ENSO on North Pacific Oscillation(NPO)was great,and the identification ability of which on Patterns I and II of summer rainfall was *** the latter phase,this identification ability decreased,while the impact of ENSO on the Pacific/North Amer

关键词： global warming climate change Three Rainfall Patterns ENSO NPO PNA prediction model

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Variations of the Magnetosphere Resonance Frequencies During Magnetic Storm of July 15-16,2000

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空间科学学报 2005年第5期25卷 387-392页

作者： A. Potapov A. Polyakov T. Polyushkina h. zhao Institute of Solar-Terrestrial Physics Siberia Branch Russian Academy of Sciences Irkutsk 664033 Russia National Microwave Remote Sensing Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences

ULF observations at two mid-latitude sites during the large geomagnetic storm of July 15-16,2000 were used to trace variations of resonance frequencies of the field line resonators. A brief description of the geomagnetic disturbance as it was observed on the ground, at the geostationary orbit, and before the Earth's bow shock is given. Then a detailed study of ULF dynamic spectra from Borok and Mondy is performed for8 succesive 6-hour intervals of July 15 and 16. In conclusion some tasks for the future work are listed.

关键词：等离子体磁场磁气圈空间气候

EVOLUTION OF AS-CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

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Acta Metallurgica Sinica(English Letters) 2003年第1期16卷 60-64页

作者： J.Dong G.M.Lu J.Z.Cui Z.h.zhao The Key Lab of Electromagnetic Processing of Materials Ministry of Education Northeastern UniversityShenyang 110004 China

A new method (liquidus casting) was used for 356 Al alloy semi-solid slurry making. The structures of 356 Al alloy cast by a Fe mould and semi-continuous casting machine at different temperatures were investigated. how the globular grains form was also discussed. The results show that either being cast by single Fe mould or semi-continuous machine, the micro structures are not conventional dendrites but fine and net-globular grains. The average gram size is smaller than 30μm and suitable enough for thixoforming, meanwhile it can improve the mechanical properties of following products. Under the suitable casting velocity and cooling intensity, most of global grains prolong their global growth and collide with each other before dendritic growth because of the large amount of the nucleation sites.

关键词： liqwdus casting microstructure 356 Al alloy

The correlationship between the metabolizable energy content,chemical composition and color score in different sources of corn DDGS

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Journal of Animal Science and Biotechnology 2014年第3期5卷 340-347页

作者： Yong-Z Jie Jian-Y Zhang Li-h zhao Qiu-G Ma Cheng Ji State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University

Background： This study was conducted to evaluate the apparent metabolizable energy （AME） and true metabolizable energy （TME） contents in 30 sources of corn distillers dried grains with solubles （DDGS） in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score. Methods： Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy （ME） contents, measured for color score and chemical composition （crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber）, to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed （50 g） to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses. Results： Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content （-0.64, P 〈 0.0]） and between ME and yellowness score （0.39, P 〈 0.05） of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 ＋ 0.5]475 GE - 0.10003 NDF ＋ 0.1 3380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R^2 = 0.70）. The best-fit regression equation for TME content of DDGS was TME = 7.92283 ＋ 0.51475 GE - 0.10003 NDF ＋ 0.13380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R2 = 0.70）. Conclusions： This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.

关键词： Metabolizable energy Distillers dried grains with solubles Rooster Predictive equation

Phase transition and dynamics of iron under ramp wave compression

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Acta Mechanica Sinica 2018年第5期34卷 902-909页

作者： T.Chong Z.P.Tang F.L.Tan G.J.Wang J.h.zhao Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621999China

The ramp wave compression experiments of iron with different thicknesses were performed on the magnetically driven ramp loading device *** simulations of this process were done with hayes multi-phase equation of state (h-MEOS) and dynamic equations of phase *** calculated results of h-MEOS are in good agreement with those of shock phase transition,but are different from those under ramp wave *** reason for this is that the bulk modulus of the material in the hayes model and the wave velocity are considered *** compression is a jump from the initial state to the final state,and the sound speed is related to the slope of the Rayleigh ***,ramp compression is a continuous process,and the bulk modulus is no longer a constant but a function of pressure and *** on Mumaghan equation of state,the first-order correction of the bulk modulus on pressure in the hayes model was carried *** numerical results of the corrected h-MEOS agree well with those of pure iron in both ramp and shock compression phase transition *** calculated results show that the relaxation time of iron is about 30 ns and the phase transition pressure is about 13 *** are obvious differences between the isentropic and adiabatic process in terms of pressure-specific volume and *** fluctuation of the sound speed after 13 GPa is caused by the phase transition.

关键词： Ramp wave compression Polymorphic phase transition Multiphase equation of state Sound speed