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Meson Effects on the Chiral Condensate at Finite Density

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Communications in Theoretical Physics 2002年第8期38卷 181-184页

作者： HUANG mei ZHUANG peng-Fei ZHAO Wei-Qin Physics Department Tsinghua University Beijing 100084 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China Physics Department Tsinghua University Beijing 100084 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100039 China

Meson corrections on the chiral condensate up to next-to-leading order in a 1/Nc expansion at finite densityare investigated in the NJL model with explicit chiral symmetry breaking. Compared with mean-field results, the chiralphase transition is still of the first order while the properties near the critical density for chiral phase transition are foundto change significantly.

关键词： meson corrections, chiral condensate

Microporous Hypercross-linked Conjugated Quinonoid Chromophores of Anthracene: Novel Polymers for CO_2 Adsorption

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Chinese Journal of Polymer Science 2015年第2期33卷 224-235页

作者： Rajangam Vinodh Mani Ganesh mei mei peng Aziz Abidov Muthiahpillai Palanichamy Wang Seog Cha Hyun-Tae Jang Department of Chemical Engineering Hanseo University Korea Carbon Capture and Sequestration R and D Centre School of Civil and Environmental Engineering Kunsan National University

Microporous hypercross-linked conjugated quinonoid chromophores represent a novel class of amorphous polymers, synthesized by the reaction of anthracene with dimethoxy methane in the presence of FeCl3 catalyst. Their N2 adsorption isotherms confirm their microporous nature. Diffuse reflectance UV-Visible（DRS UV-Vis） spectroscopy confirms their matrix built with the conjugated quinonoids by their broad light absorption characteristics extending from 1000 nm to 200 nm with the absorbance maximum close to 400 nm. The catalyst cross-linked anthracene with ―CH2― bridges and subsequently dehydrogenating them to form quinonoids. Their Fourier transform infrared（FTIR） spectra showed their characteristic quinonoid vibrations between 1600 and 1700 cm-1. The synthesis of polymers was carried out at 30, 40, 50, 60, 70 and 80 ℃, but the quinonoid content of the polymer obtained at 80 ℃ was higher than that of the others. Their scanning electron microscopy（SEM） images showed microspheres of 1 to 5 μm size built with tiny particles. Their surfaces were not smooth. The polymer synthesized at 80 ℃ showed 5.1 wt% CO2 sorption at 25 ℃ and 0.1 MPa, but when it was recross-linked, the CO2 sorption increased to 8 wt%. Hence, hypercross-linked conjugated quinonoid chromophores of anthracene are good for sorption of CO2.

关键词： Anthracene Hypercross-linked polymers CO2 adsorption Friedel-Crafts reaction Quinonoid chromophores

A polarized^(3)He system based on metastability-exchange optical pumping

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 72-81页

作者： Yuting Wang Liangyong Wu Kaiyuan Zhang mei peng Siyu Chen Haiyang Yan State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Key Laboratory of Neutron Physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang 621900China

Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and *** this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)*** employed a Merritt coil system consisting of four square coils to furnish a uniform holding *** deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical *** the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the *** applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)*** have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and *** a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 ***,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 ***,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关键词： metastability exchange optical pumping polarized^(3)He magnetic resonance

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Coumarin-derived azolyl ethanols:synthesis,antimicrobial evaluation and preliminary action mechanism

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Science China Chemistry 2016年第7期59卷 878-894页

作者： Xin-mei peng Kannekanti Vijaya Kumar Guri L.V. Damu Cheng-He Zhou Institute of Bioorganic & Medicinal Chemistry Key Laboratory of Applied chemistry of Chongqing MunicipalitySchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

A series of coumarin-derived azolyl ethanols including imidazolyl,triazolyl,tetrazolyl,benzotriazolyl,thiol-imidazolyl and thiol-triazolyl ones were conveniently synthesized and characterized by IR,~1H NMR,^(13)C NMR and high-resolution mass spectra(HRMS) *** of the prepared compounds showed appropriate logP_(ow) values and effective antibacterial and antifungal ***,compound 14 with bis-triazolyl ethanol group exhibited low minimal inhibitory concentration(MIC)value of 8 μg/mL against MRSA,which was comparable or even superior to reference drugs Norfloxacin(MIC=8μg/mL)and Chloramphenicol(MIC=16μg/mL).It could also effectively inhibit the growth of the tested fungal strains compared to *** binding studies of coumarin 14 with calf thymus DNA were investigated by UV-Vis absorption and fluorescence *** was found that compound 14 could interact with calf thymus DNA by groove binding to form14-DNA complex via both hydrogen bonds and van der Waals force,which might be the factor to exert the powerful antimicrobial activity.

关键词： coumarin imidazole triazole tetrazole antibacterial antifungal calf thymus DNA

Pharmacodynamic Mechanism of Kuanxiong Aerosol for Vasodilation and Improvement of Myocardial Ischemia

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Chinese Journal of Integrative Medicine 2022年第4期28卷 319-329页

作者： LU Yan YANG mei-ling SHEN A-ling LIN Shan peng mei-zhong WANG Tian-yi LU Zhu-qing WANG Yi-lian peng Jun CHU Jian-feng Academy of Integrative Medicine Fujian University of Traditional Chinese MedicineFuzhou350122China Chen Keji Academic Thought Inheritance Studio Fujian University of Traditional Chinese MedicineFuzhou350122China Fujian Key Laboratory of Integrative Medicine on Geriatrics Fujian University of Traditional Chinese MedicineFuzhou350122China Department of Acupuncture and Moxibustion Third People’s Hospital Affiliated to Fujian University of Traditional Chinese MedicineFuzhou350122China

Objective: To explore the effect of Kuanxiong Aerosol(KXA)on isoproterenol(ISO)-induced myocardial injury in rat ***: Totally 24 rats were radomly divided into control,ISO,KXA low-dose and high-dose groups according to the randomized block design method,and were administered by intragastric administration for 10 consecutive days,and on the 9th and 10th days,rats were injected with ISO for 2 consecutive days to construct an acute myocardial ischemia model to evaluate the improvement of myocardial ischemia by *** addition,the diastolic effect of KXA on rat thoracic aorta and its regulation of ion channels were tested by in vitro vascular tension *** influence of KXA on the expression of calcium-CaM-dependent protein kinase Ⅱ(CaMK Ⅱ)/extracellular regulated protein kinases(ERK)signaling pathway has also been ***: KXA significantly reduced the ISO-induced increase in ST-segment,interventricular septal thickness,cardiac mass index and cardiac tissue pathological changes in ***,the relaxation of isolated thoracic arterial rings that had been precontracted using norepinephrine(NE)or potassium chloride(KCl)was increased after KXA treatment in an endothelium-independent manner,and was attenuated by preincubation with verapamil,but not with tetraethylammonium chloride,4-aminopyridine,glibenclamide,or barium *** pretreatment attenuated vasoconstriction induced by CaCl_(2)in Ca^(2+)-free solutions containing K^(+) or *** addition,KXA pretreatment inhibited accumulation of Ca^(2+)in A7r5 cells mediated by KCl and NE and significantly decreased p-CaMK Ⅱ and p-ERK ***: KXA may inhibit influx and release of calcium and activate the CaMK Ⅱ/ERK signaling pathway to produce vasodilatory effects,thereby improving myocardial injury.

关键词： Kuanxiong Aerosol myocardial ischemia vasodilation Ca^(2+) CaMKⅡ/ERK pathway

Glucose,cellobiose,lactose and raffinose used as chiral stationary phases in HPLC

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Chinese Chemical Letters 2008年第10期19卷 1248-1251页

作者： Jian Yu Wang Feng Zhao mei Zhang Ya peng Li Ming Yuan Department of Chemistry Yunnan Normal University Kunming 650092 China

This paper presents the enantioseparation using glucose, cellobiose, lactose and raffinose as chiral selector bonded to silica gel via an arm in HPLC. Surprisingly, they also possess high enantioseparation selectivity, may be used in normal-phase and reversed- phase mode, and there is a big chiral discriminating complementary. This work indicates that oligosaccharides could soon become very attractive as a new class of chiral stationary phase for HPLC.

关键词： Oligosaccharides Chiral stationary phase HPLC

Design,synthesis and biological evaluation of amino organophosphorus imidazoles as a new type of potential antimicrobial agents

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Science China Chemistry 2017年第6期60卷 769-785页

作者： Wei-Wei Gao Syed Rasheed VijaiKumarReddy Tangadanchu Yi Sun Xin-mei peng Yu Cheng Feng-Xiu Zhang Jian-mei Lin Cheng-He Zhou Institute of Bioorganic&Medicinal Chemistry Key Laboratory of Applied Chemistry of Chongqing MunicipalitySchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Medicine University of Electronic Science and Technology of China Chengdu 610072China

A series of amino organophosphorus imidazoles were designed and synthesized as a novel structural type of antimicrobial *** evaluation in vitro showed that compound 3f exhibited equipotent or superior anti-methicillin-resistant Staphylococcus aureus(anti-MRSA) and anti-S. cerevisiae efficiencies(minimal inhibitory concentration(MIC)=2 μg/mL) to clinical drugs,and the combinations with antibacterial or antifungal drugs enhanced the antimicrobial efficiency. Highly active molecule 3f showed low propensity for bacteria to develop resistance, and the preliminary action mechanism studies demonstrated that 3f was membrane-active, but had no significant intercalation towards MRSA DNA. The computational study on 3f reasonably explained its high antimicrobial activity. Experimental data revealed that ground-state 3f-HSA complexes were formed mainly through hydrophobic interactions and hydrogen bonds with a spontaneous process, and the non-radioactive energy transfer from HSA to 3f occurred beyond F鰎ster resonance energy transfer theory. The participation of metal ions in 3f-HSA supramolucular system could increase the concentration of free compound 3f, and shorten its storage time and half-life in the blood to improve the maximum antimicrobial efficacy.

关键词： organophosphorus imidazole antibacterial antifungal HSA

亚临界萃取和膜技术精制元宝枫籽油的工艺优化

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食品工业科技 2025年第1期46卷 208-217页

作者：冉娴婷王瑜李立郎张朝举罗忠圣彭梅杨娟贵州大学酿酒与食品工程学院贵州贵阳550025 贵州医科大学省部共建药用植物功效与利用国家重点实验室贵州贵阳550014 贵州省天然产物研究中心贵州贵阳550014

为了提高元宝枫籽油(ASO)的质量特性和储藏稳定性,对亚临界萃取得到的元宝枫籽油进行精制,以去除磷脂、过氧化物和游离脂肪酸。本文对亚临界萃取ASO的提取工艺进行优化,并对得到的原油利用膜分离技术进行脱胶精制,以膜通量,脱胶率、碘... 详细信息

为了提高元宝枫籽油(ASO)的质量特性和储藏稳定性,对亚临界萃取得到的元宝枫籽油进行精制,以去除磷脂、过氧化物和游离脂肪酸。本文对亚临界萃取ASO的提取工艺进行优化,并对得到的原油利用膜分离技术进行脱胶精制,以膜通量,脱胶率、碘值、过氧化值、酸价为指标,对不同孔径的陶瓷膜和不同截留分子量的聚醚砜膜进行筛选。考察膜截留分子量、温度和压力对膜通量的影响;通过响应面法,确定ASO精制的最佳工艺参数。同时采用气相色谱-质谱法比较精制前后脂肪酸的含量。结果表明,当粒径为30目、萃取温度50℃,固液比为1:4 g/mL,聚醚砜膜分子量为100 kD,温度44℃,压力1.9 MPa,ASO得油率均值为35.92%,脱胶率为86.73%,通量为12.51 L/m2·h,碘值为116.93 g/100 g,过氧化值为0.06 g/100 g,酸价为3.66 g/100 g,与原油相比脂肪酸含量无明显损失。研究结果显示,用膜分离法脱胶是一种提高油脂品质的有效手段,本研究可为优质元宝枫籽油的生产提供技术支持。

关键词：元宝枫籽油(ASO) 亚临界萃取膜分离聚醚砜有机膜脱胶脂肪酸

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Controlled Synthesis and Electrochemical Behavior of Single-crystal MoO_2 Nanowhiskers by a Facile Precursor-reduction Route

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Chinese Chemical Letters 2006年第6期17卷 825-828页

作者： Yu mei KONG Jun peng Feng Shan SHEN Bao Xia DONG Li Ll Key Laboratory of Polyoxometalate Science of Ministry of Education Faculty of Chemistry Northeast Normal University Changchun 130024

A novel method for controlled synthesis of crystalline molybdenum dioxides nanowhiskers （whisker-MoO2） by using moderate reductive and precursor ion under hydrothermal conditions is reported. The result shows that the as-obtained samples have a monoclinic structure, and the whisker-MoO2 is composed of nanowires with diameters of ca. 20 nm. Formation of whisker-MoO2 was through a typical precursor-reduction process, in which cetyltrimethylammonium bromide （CTAB） served as a cationic surfactant and acetone as a reductant. The electrochemical behavior of whisker-MoO2 was studied.

关键词： Synthetic methods characterization MoO2 nanowhiskers electrochemical behavior.