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Prediction verification of solar cycles 18–24 and a preliminary prediction of the maximum amplitude of solar cycle 25 based on the Precursor Method

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Research in Astronomy and Astrophysics 2020年第1期20卷 27-34页

作者： juan miao Xin Wang Ting-Ling Ren Zhi-Tao Li National Space Science Center Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Predictions of the strength of solar cycles are important and are necessary for planning long-term missions.A new solar cycle 25 is coming soon,and the amplitude is needed for space weather *** predictions have been made using different methods and the values are drastically ***,since 2015 July 1,the original sunspot number data have been entirely replaced by the Version 2.0 data series,and the sunspot number values have changed *** this paper,using Version 2 smoothed sunspot numbers and aa indices,we verify the predictions for cycles 18-24 based on Ohl’s Precursor *** a similar-cycles method is used to evaluate the aa minimum of 9.7(±1.1)near the start of cycle 25 and based on the linear regression relationship between sunspot maxima and aa minima,our predicted Version 2maximum sunspot number for cycle 25 is 121.5(±32.9).

关键词： solar cycle sunspot geomagnetic aa indices

Hydrophobic surface modification of chitosan gels by stearyl for improving the activity of immobilized lipase

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Chinese Chemical Letters 2009年第8期20卷 995-999页

作者： Hong Tao Deng juan juan Wang miao Ma Zhong Yang Liu Fei Zheng College of Chemistry Central China Normal University Wuhan 430079 China

The hydrophobic surface modification of chitosan gels was carried out using the amidating reaction of amido groups on a gel surface with stearic acid activated by 1-ethyl-3-（3-dimethylaminopropyl）-carbodiimide hydrochloride （EDC） and N-hydroxysuccinimide （NHS）. Lipases from Candida rugosa were adsorbed on the nascent chitosan gels （CS） and stearyl-modified gels （SCS） with different degrees of amidation. The increased surface hydrophobicity of chitosan gels improved the adsorption capacity and activity of the immobilized lipase. SCS with 31.46% amidation showed the maximum activity retention （83.43%）. The experimental results suggest that the moderate surface hydrophilicity/hydrophobicity of chitosan gels is necessary for the improvement of the activity of immobilized lipase. ？2009 Hong Tao Deng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Lipase Chitosan Surface modification Adsorption

Prediction of the smoothed monthly mean sunspot numbers for solar cycle 24

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Science China(Physics,Mechanics & Astronomy) 2008年第12期51卷 1938-1946页

作者： WANG JiaLong miao juan LIU SiQing GONG JianCun ZHU CuiLian National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100080China

The prediction for the smoothed monthly mean sunspot numbers (hereafter SMSNs) of solar cycle 23, which was given with a similar cycle method proposed by us at the beginning time of cycle 23, is analyzed and verified in this paper. Using our predicted maximum SMSN and the ascending length for solar cycle 24, and as- suming their relative errors to be respectively 20% and ± 7 months, solar cycles 2, 4, 8, 11, 17, 20 and 23 are selected to be the similar cycles to cycle 24. The selected solar cycles are divided into two groups. The first group consists of all the selected cycles; while the second group consists of only cycles 11, 17, 20 and 23. Two SMSN time profiles then may be obtained, respectively, for the two similar cycle groups. No significant difference is found between the two predicted time profiles. Consid- ering the latest observed sunspot number so far available for cycle 23 and the pre- dictions for the minimum SMSN of cycle 24, a date calibration is done for the ob- tained time profiles, and thus, SMSNs for 127 months of cycle 24, from October 2007 to April 2018, are predicted.

关键词： solar cycle sunspot numbers prediction of cycle 24

High-temperature nodal ring semimetal in two-dimensional honeycomb-kagome Mn_(2)N_(3) lattice

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Chinese Physics B 2022年第12期31卷 477-483页

作者： Xin-Ke Liu Xin-Yang Li miao-juan Ren Pei-Ji Wang Chang-Wen Zhang School of Physics and Technology University of JinanJinan 250022China

The search for two-dimensional(2D)nodal ring semimetallic materials is a current research hotspot in spintronics,and designing a 2D nodal ring(NR)material with high Curie temperature(TC)and strong robustness to spin-orbit coupling(SOC)is an even greater ***,based on the first-principles calculations and symmetry analysis,we predict that 2D Mn_(2)N_(3)is a nodal ring semimetal(NRSM)with three energy bands near the Fermi energy level consisting of electrons in the same spin *** electron-like energy band and two hole-like energy bands near the Fermi plane cross to form two NRs centered at the pointΓ.Symmetry analysis shows that the spin-polarized NR semimetal is robust to SOC due to the conservation of horizontal mirror ***-Carlo simulations further demonstrate that the TCof the 2D Mn_(2)N_(3)reaches 530 K,well above the room ***,the 2D Mn_(2)N_(3)remains an NRSM on h-BN *** results not only reveal a general framework for designing 2D NR materials,but also promote further research in the direction of multifunctional quantum devices for spintronics.

关键词： first-principles calculation semi-metal nodal ring Curie temperature

Huangqi Decoction,a compound Chinese herbal medicine,inhibits the proliferation and activation of hepatic stellate cells by regulating the long noncoding RNA-C18orf26-1/microRNA-663a/transforming growth factor-βaxis

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Journal of Integrative Medicine 2023年第1期21卷 47-61页

作者： Ben-sheng Dong Fu-qun Liu Wen-na Yang Xiao-dong Li miao-juan Shi Mao-rong Li Xiu-li Yan Hui Zhang Traditional Chinese Medicine Epigenomics Research Center Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghai 201203China Department of Rheumatology and Immunology Nanjing Lishui District Hospital of Traditional Chinese MedicineNanjing 211299Jiangsu ProvinceChina Department of Rheumatology and Immunology Yangzhou University Medical CollegeYangzhou 225000Jiangsu ProvinceChina Department of Cardiovascular Physiology Faculty of MedicineKagawa UniversityKita-gunKagawa 761-0793Japan Department of Gastroenterology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China

Objective Huangqi Decoction(HQD),a classical traditional Chinese medicine formula,has been used as a valid treatment for alleviating liver fibrosis;however,the underlying molecular mechanism is still *** our previous studies showed that microRNA-663a(miR-663a)suppresses the proliferation and activation of hepatic stellate cells(HSCs)and the transforming growth factor-β/small mothers against decapentaplegic(TGF-β/Smad)pathway,whether long noncoding RNAs(lncRNAs)are involved in HSC activation via the miR-663a/TGF-β/Smad signaling pathway has not yet *** present study aimed to investigate the roles of lncRNA lnc-C18orf26-1 in the activation of HSCs and the mechanism by which HQD inhibits hepatic *** The expression levels of lnc-C18orf26-1,miR-663a and related genes were measured by quantitative reverse transcription-polymerase chain *** were transfected with the miR-663a mimic or inhibitor and lnc-C18orf26-1 small interfering *** water-soluble tetrazolium salt-1 assay was used to assess the proliferation rate of *** in lncRNA expression were evaluated in miR-663a-overexpressing HSCs by using microarray to identify miR-663a-regulated *** hybrid was used to predict the potential miR-663a binding sites on *** reporter assays further confirmed the interaction between miR-663a and the *** expression levels of collagen α-2(I)chain(COL1A2),α-smooth muscle actin(α-SMA)and TGF-β/Smad signaling pathway-related proteins were determined using Western *** Lnc-C18orf26-1 was upregulated in TGF-β1-activated HSCs and competitively bound to *** of lnc-C18orf26-1 inhibited HSC proliferation and activation,downregulated TGF-β1-stimulatedα-SMA and COL1A2 expression,and inhibited the TGF-β1/Smad signaling *** suppressed the proliferation and activation of *** increased miR-663a expression and decreased lnc-C18orf26-1 expression in *** studies showed tha

关键词： Longnoncoding RNA-C18orf26-1 MicroRNA-663a Transforming growth factor-β Hepatic stellate cells Huangqi Decoction

黏弹性问题的改进的复变量无单元Galerkin方法

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物理学报 2014年第18期63卷 40-48页

作者：彭妙娟刘茜上海大学土木工程系上海200072

基于改进的复变量移动最小二乘法,提出了二维黏弹性问题的改进的复变量无单元Galerkin方法.采用改进的复变量移动最小二乘法建立形函数,根据Galerkin积分弱形式建立求解方程,并用罚函数法施加本质边界条件,推导了二维黏弹性问题的改进... 详细信息

基于改进的复变量移动最小二乘法,提出了二维黏弹性问题的改进的复变量无单元Galerkin方法.采用改进的复变量移动最小二乘法建立形函数,根据Galerkin积分弱形式建立求解方程,并用罚函数法施加本质边界条件,推导了二维黏弹性问题的改进的复变量无单元Galerkin方法的计算公式.最后,通过实际算例,将计算结果与复变量无单元Galerkin方法及有限元法的结果进行了对比,说明了本文方法具有更高的计算精度和计算效率.

关键词：无网格方法复变量移动最小二乘法改进的复变量无单元Galerkin方法黏弹性问题

Extraction of quinine and gramine from the water using ionic liquids

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Extraction of quinine and gramine from the water using ionic...

Enhanced extraction of antioxidants from aqueous solutions by ionic liquids

河南省化学会2016年学术年会

作者： Xiaojing Li Yunchang Fan juan miao College of Chemistry and Chemical Engineering Henan Polytechnic University

Ionic liquids(ILs), as "green solvents" alternatives to conventional volatile organic solvents due to their negligible vapour pressures preventing the further emissions to the atmosphere, high specific solvent ability, chemical and thermal stability, have been used in various applications, such as organic synthesis, catalysis, separation and extraction science. In recent years, imidazolium-based ILs used in extraction of organic compounds have achieved huge developments. In this work, a series of new structure ILs were synthesized. The extraction abilities of these ILs were investigated, and based on the studies of these parameters affected the extraction efficiency including p H values, phase ratio,temperature and extraction time were optimized systematically. ILs, including [CCim]ClO,[CCim]PF, [CCim]BF, [CCim]CFSO and [CCim]NTf(n = 6, ,10), were used in extraction of quinine and gramine. The results show that the extraction abilities of ILs follow the order[CCim]PF ≈ [CCim]PF ≈ [CCim]PF_ < [CCim]NTf ≈ [CCim]NTf2 ≈ [CCim]NTf2 <[CCim]ClO ≈ [CCim]Cl O ≈ [CCim]Cl O ≈ [CCim]BF ≈ [CCim]BF ≈ [CCim]BF <[CCim]CFSO ≈ [CCim]CFSO ≈ [CCim]CFSO, indicating that the hydrogen-bond interaction is one of the most important driving forces. In a summary, 1) The extraction efficiencies of alkaloids quinine and gramine depend on the p H values of water and phase volume ratio;2) The extraction efficiencies of alkaloids are not affected by the concentration of alkaloids;3) Thermodynamic analysis suggests that hydrophobic interactions are the main driven forces of the extraction processes transferring the alkaloids from water to IL phase.

关键词： ionic liquids extraction quinine gramine

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Enhanced extraction of antioxidants from aqueous solutions b...

Kinetics of medium-temperature α-amylase hydrolyzed <i>Huai yam</i>powder

河南省化学会2016年学术年会

作者： Xin Wang Yunchang Fan juan miao College of Chemistry and Chemical Engineering Henan Polytechnic University

In this work, the extraction behavior of the three antioxidants, gallic acid(GA), vanillic acid(VA)and syringic acid(SA) by a series of hydrophobic ionic liquids(ILs) was investigated. The experimental results indicated that the extraction ability of the ILs highly depended on their chemical structures and the hydrophobicity of the three acids. For the ILs with perchlorate(ClO) as anion, the introduction of hydroxyl group on the cation improved significantly the extraction ability of ILs for GA. For the extraction of VA and SA, the hydrophobic interaction of ILs and VA or SA should also be *** analysis confirmed that hydrogen bonding was the main driving force underlying the transfer of the three acids from water to the IL phase. The three acids and ILs could be recovered and recycled, respectively by taking the advantage of p H dependence of the extraction efficiencies. These results suggested the hydroxyl ILs containing perchlorate anion exhibited potential applications in extraction of the three antioxidants from aqueous phase.

关键词： ionic liquids(ILs) extraction antioxidants hydrogen bonding hydrophobic interaction

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Agricultural Sciences 2013年第9期4卷 5-11页

作者： juan miao Yunchang Fan Jingjing Li Dexue Fu Department of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China Jiaozuo University Jiaozuo 454000 China

In order to learn the enzymatic characteristics of Huai yam powder with medium-temperatureα-amylase, effects of substrate concentration,enzyme concentration, pH and temperature wereinvestigated. The Michealis-Menten equationwas used to fit the kinetics of the hydrolysis reaction. Experimental results indicate that maximum rate (Vm) is 3.1588 mg/mL·min under the condition of 70°C, pH 7.0 and 0.0200 mg/mL of enzyme concentration. The Michealis constant (Km) is 6.6641 mg/mL. The kinetic model, including the factors such as substrate concentration, enzyme concentration and temperature, was established for the hydrolysis reaction under the temperature range from 40°C - 70°C.

关键词： Huai Yam Medium-Temperature α-Amylase Hydrolysis Kinetics