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Classification of Positive Solutions to a Divergent Equation on the Upper Half Space

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Acta Mathematica Sinica,English Series 2022年第3期38卷 499-509页

作者： jin Ge yao jing Bo DOU School of Mathematics and Statistics Shaanxi Normal UniversityXi’an710119P.R.China

In this paper we classify the positive solutions of the divergent equation with Neumann boundary on the upper half space{-div(t^(α)∇u)=t^(β)f(u),(y,t)∈R^(n+1)_(+),lim t→0^(+)t^(α)■u/■t=0 by the method of moving spheres and Kelvin transformations,where n≥1,α>0,β>−1,n−1/n+1β≤α<β+2,and f:(0,∞)→(0,∞)is non-negative continuous function satisfying some *** equation arises from a weighed Sobolev inequality involving divergent operator div(t^(α)∇u)on the upper half space.

关键词： Divergent operator Liouville theorem Neumann boundary method of moving spheres Kelvin transformation

Advance of large-area achromatic flat lenses

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Light(Science & Applications) 2023年第3期12卷 318-320页

作者： Yubin Fan jin yao Din Ping Tsai Department of Electrical Engineering City University of Hong KongKowloonHong Kong 999077China Centre for Biosystems Neuroscienceand NanotechnologyCity University of Hong KongKowloonHong Kong 999077China The State Key Laboratory of Terahertz and Millimeter Waves City University of Hong KongKowloonHong Kong 999077China

A new framework of light coherence optimization is proposed to design non-ideal broadband achromatic lenses,enabling large-scale flat lenses'implementation and high *** strategy paves the way for practical planar opti... 详细信息

关键词： chromatic planar optimization

Preparation of calcium carbonate with microstructure and nanostructure from carbide slag for CO_(2) sequestration by using recyclable ammonium chloride

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Particuology 2024年第7期90卷 1-9页

作者： jin yao Qiuju Chen Li Zeng Wenjin Ding Key Laboratory of Ministry of Education for Solid Waste Treatment and Resource Recycle Southwest University of Science and TechnologyMianyang621010China Sichuan Engineering Lab of Non-metallic Mineral Powder Modification and High-value Utilization Mianyang621010China School of Architecture and Civil Engineering Chengdu UniversityChengdu610106China

Based on the composition characteristics of carbide slag and the application of polyvinyl chloride,a method of preparing calcium carbonate with microstructure and nanostructure by using carbide slag as a raw material and ammonium chloride as a leaching agent was *** factors for the preparation of calcium carbonate and the effects of different conditions on the crystal phase,grain size,and morphology of calcium carbonate were systematically *** results showed that the nanosized calcium carbonate was prepared at 60 mL/min,25°C,no additional ammonia,and 60 *** product of spherical vaterite was in accordance with the relevant standards for the industrial precipitation of calcium ***,the reuse of carbonation filtrate was *** crystal phase,grain size,and morphology of the carbonation product could be controlled by adjusting the reaction *** manuscript provided a new idea for resource utilization of carbide slag and preparing nanocalcium carbonate.

关键词： Carbide slag Ammonium chloride Cyclic utilization Micro and nano structure Product control

Microstructural characterization of Cu/Al composites and effect of cooling rate at the Cu/Al interfacial region

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 94-101页

作者： Yan-qiu Han Li-hua Ben jin-jin yao Chun-jing Wu School of Materials Science and Engineering University of Science and Technology Beijing

Cu/Al composites are of vital importance in industrial applications because of their numerous advantages. The influence of bond-ing temperature and cooling rate on the microstructure and morphology of Cu/Al composites was investigated in this paper. The interfacial morphology and constituent phases at the Cu/Al interface were analyzed by optical microscopy and field-emission scanning electron mi-croscopy equipped with energy-dispersive X-ray spectroscopy. The results indicate that effective Cu-Al bonding requires a higher bonding temperature to facilitate interdiffusion between the two metals. The microstructural characteristics are associated with various bonding tem-peratures, which impact the driving force of interdiffusion. It is observed that cooling rate exerts a significant influence on the morphology and amount of the intermetallic compounds at the interfacial region. Meanwhile, microhardness measurements show that hardness varies with the bonding temperature and rate of cooling.

关键词： composite materials copper aluminum temperature cooling rate interfaces diffusion bonding

Adsorption of Human Serum Albumin onto PVA-coated Affinity Microporous PTFE Capillary

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Chemical Research in Chinese Universities 2008年第2期24卷 154-161页

作者： jin Gu yao Qi-zhi ZHANG Lei Department of Chemistry University of Science and Technology of China Hefei 230026 P. R. China

Affinity dye-ligand Cibacron Blue F3GA（CB F3GA） was covalently coupled with poly（vinyl alcohol）（PVA） coated on the inner surface of microporous poly（tetra-fluoroethylene）（MPTFE） membranous capillary. The PVA-coated PTFE capillary surface was characterized by XPS and FESEM. The grafting degree of PVA and the amount of CB F3GA immobilized onto the membranous capillary were 23.5 mg/g and 89.6 pmol/g, respectively. These dyed membranous capillaries were chemically and mechanically stable, and could be reproducibly prepared. Human serum albumin（HSA） was selected as model protein. The saturation adsorbance of the dye attached membranous capillary was 85.3 mg HSA/g, while the capacity of non-specific adsorption for HSA was less than 0.3 mg/g.

关键词： Albumin adsorption Cibacron blue F3GA PVA PTFE Plasma

Intrinsic kinetics of methane aromatization under non-oxidative conditions over modified Mo/HZSM-5 catalysts

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Journal of Natural Gas Chemistry 2008年第1期17卷 64-68页

作者： Benzhen yao jin Chen Dianhua Liu Dingye Fang State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

The intrinsic reaction kinetics of methane aromatization under non-oxidative conditions over modified Mo/HZSM-5 catalysts was studied in the quartz pipe-reactor under ordinary pressure with the temperature ranging from 913.15 to 973.15 K and the space velocity from 700 to 2100 ml/（g·h）. The Langmuir-Hinshelwood model was chosen to describe the intrinsic kinetics while Levenberg-Marquardt method was selected to determine the parameters in the kinetic model. Statistical test and residual error distribution diagrams showed that experimental data were in good agreement with calculated data, and Langmuir-Hinshelwood model was suitable for the description of the intrinsic kinetics of methane aromatization under the reaction conditions discussed in this article.

关键词： methane aromatization intrinsic kinetics Mo/HZSM-5 non-oxidative

Pore Engineering for Covalent Organic Framework Membranes

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Chemical Research in Chinese Universities 2022年第2期38卷 364-372页

作者： yao jin LU Ya SUN Huihui ZHAO Xin Key Laboratory of Synthetic and Self-assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032P.R.China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024P.R.China College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234P.R.China

Membrane technology is of particular significance for the sustainable development of society owing to its potential capacity to tackle the energy shortage and environmental *** materials are the core part of membrane *** have always been pursuing predictable structures of advanced membrane materials,which provides a possibility to fully unlock the potential of *** organic frameworks(COFs),with the advantage of controllable pore microenvironment,are considered to be promising candidates to achieve this design *** customizable function of COF membranes through pore engineering does well in the enhancement of selective permeability performance,which offers COF membranes with great application potentials in separation and transportation *** this context,COF-based membranes have been developed rapidly in recent ***,we present a brief overview on the strategies developed for pore engineering of COF membranes in recent years,including skeleton engineering,pore surface engineering,host-guest chemistry and membrane ***,the features of transmission or separation of molecules/ions based on COF membranes and corresponding applications are also *** the last part,the challenges and prospects of the development of COF membranes are discussed.

关键词： Membrane technology Covalent organic framework(COF) Pore engineering Separation Ion transportation

Mapping Analysis of Solar Radio Burst at 17 GHz on 1992 October 27

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Chinese Physics Letters 2000年第8期17卷 621-622页

作者： YU Xing-Feng yao jin-Xing Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatory Chinese Academy of Sciences

The contour maps at 17 GHz on the 1992 October 27 solar burst are *** a nonthermal inhomogeneous model of the radio source,the variations of calculated source size with time are basically consistent with the observation of *** variations of calculated brightness temperature with a distanceρdisplaced from the project center are in better agreement with the observation of map at 01:45:29:889 *** calculation shows that the characterizing magnetic field gradientαB at the peak of 17 GHz is about 2,magnetic strength B is about 737G with the magnetic field Bm of the core being 2000 *** in order to measure the coronal magnetic field accurately,it is necessary to obtain radio-imaging data at more frequencies.

关键词： strength magnetic Solar

Numbers of Electrons in Solar Flares as Deduced from Microwave and X-Ray Bursts

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Chinese Physics Letters 2001年第3期18卷 455-457页

作者： YU Xing-Feng yao jin-Xing Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 tional Astronomical Observatory Chinese Academy of Sciences

We discuss Whether the numbers of x-ray and radio-produced electrons in solar flares are the *** number of the radio-produced electrons that is estimated with an inhomogeneous source increases by a factor of 10^(3)-10^(4) because of the inhomogeneity and the decreased magnetic field(B=120 G)of the radio *** number of the x-ray-produced electrons decreases by a factor of 10-30 due to the increase of the number density of ions(3 × 10^(10)cm^(-3)).These are the reasons why the number of radio-produced electrons is approximately equal to that of x-ray produced in the 1981 April 27 burst.

关键词： source Solar source