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Application of the annexation principle to the thermodynamic property study of ternary metallic melts In-Bi-Cu and In-Sb-Cu

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Journal of university of science and technology beijing 2002年第3期9卷 170-176页

作者： Man zhangmetallurgy school,{2., beijing 100083, China (Received 2.01-10-2.) Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the phase diagrams, measured activities and the annexationprinciple, calculating models of mass action concentrations for In-Bi-Cu and In-Sb-Cu melts havebeen formulated. Calculated results not only agree well with practical values, but also obey themass action law, showing that the deduced model can reflect the structural reality of given meltasand that the annexation principles is applicable to these tow ternary metallic melts. So long asthere is one from three binary systems constituting the ternary melts, in which the activities ofone component exhibit positive deviation relative to Raoultian behavior, heterogeous meltsinevitably would form, so heterogeneous calculating model should be used to calculate their massaction concentrations. On the contrary, if all the binary melts are homogeneous and their activitiesexhibit negative deviation with respect to the Raoult's law, then the ternary melts formed fromthem will certainly be homogeneous, hence single phase model should be applied.

关键词： activity mass action concentration coexistence theory annexationprinciple

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen jian-Jun He Key Laboratory of Beam technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2. H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Pd-catalyzed asymmetric carbonyl alkynylation:Synthesis of axial chiral ynones

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Chinese Chemical Letters 2024年第6期35卷 293-297页

作者： Long Jin jian Han Dongmei Fang Min Wang jian Liao Natural Products Research Center Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China College of Chemical Engineering Sichuan UniversityChengdu 610065China university of Chinese Academy of sciences Beijing 100049China

Ynones are important skeletons in bioactive molecules and valuable building blocks for organic synthesis,thus great efforts have been devoted to their ***,introducing prochiral substrates to construct ynones bearing a chiral framework is unrealized to ***,we reported the first example of Pd/SOP-catalyzed asymmetric carbonylative alkynylation via a non-classical carbonylative Sonogashiratype approach(acyl-Pd(Ⅱ)species generated from nucleophiles).By using cyclic diaryliodonium salts as prochiral substrates,various axial chiral ynones with good functional group tolerance(39 examples),satisfied yields(71%-96%)and excellent enantioselectivities(generally 94%-99%ee)were *** of bioactive compounds,scale-up experiment and useful transformations were also conducted to demonstrate the utility of this process.

关键词： Pd-catalyzed Axial chiral ynones Cyclic diaryliodonium High-valent palladium catalyzed Asymmetric carbonyl alkynylation

Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： jian Yu Zhong-Lin Wang Tianwei Ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life ***,because of limited performance,existing systems do not lend themselves to practical *** it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive ***,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the *** findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

Applicability of mass action law to sulphur distribution between slag melts and liquid iron

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Journal of university of science and technology beijing 2002年第2期9卷 90-98页

作者： jian Zhang Metallurgy school,{2., beijing 100083, China Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

According to the mass action law and the coexistence theory of slagstructure, the calculating models of mass action concentration for CaO-MgO-FeO-Fe_2._3-SiO_2.CaO-MgO-MnO-FeO-Fe_2._3-P_2._5-SiO_2.and CaO-MgO-MnO-FeO-Fe_2._3-Al_2._3-P_2._5-SiO_2.slag melts areformulated and sulphur distribution between the slag melts and liquid iron is treated. It is foundthat CaO, MnO and FeO promote desulphurization, while MgO is detrimental to desulphurization. Inaddition, the sulphur distribution coefficients between the slag melts and liquid iron andpresented.

关键词： mass action law coexistence theory of slag structure activity massaction concentration

Interface interaction between SiO_(2. and magnetite under high temperature:particle migration and inhibition mechanism

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Journal of Iron and Steel Research(International) 2024年第3期31卷 561-572页

作者： Yao-zu Wang jian-liang Zhang Qiang Cheng Hui-qing jiang Zheng-jian Liu Yu-bo Tan school of Intelligent science and {2. University of Science and Technology BeijingBeijing 100083China school of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China school of Advanced Engineering University of Science and Technology BeijingBeijing 100083China

Silicon is one of the main gangue components in iron ore,usually in the form of quartz and *** studies have shown that SiO_(2. has a two-sided effect on the consolidation of pellets during high-temperature oxidation roasting of ***,it is very difficult to capture the structural evolution and migration mechanisms during high-tem-perature roasting process by existing experimental ***,the influence of SiO_(2. on the consolidation behavior of magnetite was studied through a series of roasting experiments and molecular dynamic *** results show that the consolidation index and particle growth index decrease with the increase in SiO_(2. content in the *** 1573 K,the liquid phase promotes the recrystallization growth of hematite at high *** dynamic study shows that it is difficult for quartz SiO_(2. to form sintering neck with Fe_(2.O_(3).When the calcination temperature is higher than 1400 K,the Fe_(2.O_(3)-Fe_(2.SiO_(4) system produces a considerable sintering neck structure after *** atomic migration ability of Fe_(2.SiO_(4) is much higher than that of Fe_(2.O_(3).The higher atomic migration ability of Fe_(2.SiO_(4) is the main reason for the formation of the sintering neck.

关键词： Sintering neck Crystal growth Consolidation Molecular dynamics SiO_(2.

Calculating model of mass action concentrations for Ag-Au-Cu melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG jian Metallurgy school,{2., beijing 100083, China Metallurgy school University of Science and Technology Beijing 北京 100083

Based on phase diagrams and measured activities, the calculatingmodel of mass action concentrations for het- erogeneous meltsAg-Au-Cu was formulated. Calculated results agree with the improvedresults of recent research work, Showing that the model formulatedcan reflect the structural characteristics of these melts. In thismodel, without the help Of any empirical parameters, only threeequilibrium constants are used, hence it is simple, lear, andfavorable to the sim- Plification of calculation.

关键词： activity mass action concentration eutectic Solid solution

Persymmetric adaptive polarimetric detection of subspace range-spread targets in compound Gaussian sea clutter

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Journal of Systems Engineering and Electronics 2024年第1期35卷 31-42页

作者： XU Shuwen HAO Yifan WANG Zhuo XUE jian National Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China Xi’an Electronic Engineering Research Institute Xi’an 710100China beijing Institute of Radio Measurement Beijing 100039China school of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

This paper focuses on the adaptive detection of range and Doppler dual-spread targets in non-homogeneous and nonGaussian sea *** sea clutter from two polarimetric channels is modeled as a compound-Gaussian model with different parameters,and the target is modeled as a subspace rangespread target *** persymmetric structure is used to model the clutter covariance matrix,in order to reduce the reliance on secondary data of the designed *** adaptive polarimetric persymmetric detectors are designed based on the generalized likelihood ratio test(GLRT),Rao test,and Wald *** the proposed detectors have constant falsealarm rate property with respect to the clutter texture,the speckle covariance *** results on simulated and measured data show that three adaptive detectors outperform the competitors in different clutter environments,and the proposed GLRT detector has the best detection performance under different parameters.

关键词： sea clutter adaptive polarimetric detection compound Gaussian model subspace range-spread target persymmetric structure

Calculating Models of Mass Action Concentrations for Ni-Mn and Co-Mn Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 246-250页

作者： jian Zhang (Metallurgy school,{2., beijing 100083, China) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

According to phase diagrams, measured activities as well as the coexistence theory of motallic melts structure involving compound formation, the calculating models of mass action concentrations for Ni-Mn and Co-Mn melts are formulated and their thermodynamic parameters are optimized. As a result, the calculated mass action concentrations agree well with the corresponding measured activities, showing that these models can reflect the structural characteristics of both Ni-Mn and Co-Mn melts.

关键词： activity metallic melts coexistence theory mass action concentration