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Using Raman Spectroscopy and ab initio Calculations to Investigate Intermolecular Hydrogen Bonds in Binary Mixture (Tetrahydrofuran+Water)

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Chemical Research in Chinese Universities 2011年第4期27卷 693-696页

作者： WU Nan-nan ouyang shun-li li Zuo-wei liU Jing-yao GAO Shu-qin State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 R R. China College of Physics Jilin University Changchun 130012 P. R. China

We analyzed the properties and structures of the hydrogen-bonded complexes of tetrahydrofuran（THF） and water by means of experimental Raman spectra and ab initio *** optimized geometries and vibrational frequencies of the neat THF molecule and its hydrogen-bonded complexes with water（THF/H2O） were calculated at the MP2/6-311＋G（d,p） level of *** found that the intermolecular hydrogen bonds which are formed from the binary mixtures of the neat THF and water with different molar ratios could explain the changes in wavenumber position and linewidth very *** combination of ab initio calculations and experimental Raman spectral data provides an insight into the hydrogen bonds leading to the concentration dependent changes in the spectral features.

关键词： Hydrogen bond Raman spectroscopy Ab initio calculation

Spectra of linear Polyene Molecule-canthaxanthin

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Chemical Research in Chinese Universities 2011年第4期27卷 661-663页

作者： ouyang shun-li li Zuo-wei CHEN Yuan-zheng MEN Zhi-wei WU Nan-nan SUN Cheng-lin State Key Laboratory of Superhard Materials College of Physics Jilin University Changehun 130012 P. R. China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changehun 130021 P. R. China

Raman spectra and ultraviolet-visible（UV-Vis） absorption spectra of linear polyene molecule-canthaxan-thin in n-hexane are measured and *** addition,the optimized structure of canthaxanthin was calculated via density functional theory（DFT） functional *** decreasing the concentration,Raman scattering cross section （RSCS） of fundamental frequency is extremely high,and the UV-Vis absorption bands become *** results of coherent weakly damped electron-Lattice vibration model were analyzed.

关键词： Raman spectroscopy Ultraviolet-visible absorption spectrum Canthaxanthin

RNA modifications in the progression of liver diseases:from fatty liver to cancer

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Science China(life Sciences) 2024年第10期67卷 2105-2119页

作者： Simiao li Wajahat Z Mehal Xinshou ouyang Department of Internal Medicine Section of Digestive DiseasesYale University School of MedicineNew Haven CT 06520USA

Non-alcoholic fatty liver disease(NAFLD)has emerged as a prominent global health concern associated with high risk of metabolic syndrome,and has impacted a substantial segment of the *** disease spectrum ranges from simple fatty liver to non-alcoholic steatohepatitis(NASH),which can progress to cirrhosis and hepatocellular carcinoma(HCC)and is increasingly becoming a prevalent indication for liver *** existing therapeutic options for NAFLD,NASH,and HCC are limited,underscoring the urgent need for innovative treatment *** into gene expression,particularly RNA modifications such as N6methyladenosine(m^(6)A),hold promising avenues for *** modifications play integral roles in RNA metabolism and cellular functions,encompassing the entire NAFLD-NASH-HCC *** review will encompass recent insights on diverse RNA modifications,including m^(6)A,pseudouridine(Ψ),N^(1)-methyladenosine(m^(1)A),and 5-methylcytidine(m^(5)C)across various RNA *** will uncover their significance in crucial aspects such as steatosis,inflammation,fibrosis,and ***,prospective research directions and therapeutic implications will be explored,advancing our comprehensive understanding of the intricate interconnected nature of these pathological conditions.

关键词： m^(6)A RNA modification NASH NAFLD HCC fatty liver

Ultrathin organic solvent nanofiltration membrane with polydopamine-HKUST-1 interlayer for organic solvent separation

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Journal of Environmental Sciences 2024年第7期141卷 182-193页

作者： Haike li Xindong li Guozai ouyang lijinhong Huang Lang li Wenhao li Wanfu Huang Duokun li Ganzhou Key Laboratory of Basin Pollution Simulation and Control Jiangxi University of Science and TechnologyGanzhou 341000China Innovation Center for Water Quality Security Technology at Ganjiang River Basin Jiangxi University of Science and TechnologyGanzhou 341000China School of Architecture and Design Jiangxi University of Science and TechnologyGanzhou 341000China WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityWA 6845Australia School of Materials Science and Engineering Tiangong UniversityTianjin 300387China

Polydopamine(PDA)and metal-organic skeleton HKUST-1 were co-deposited on the base membrane of hexamethylenediamine(HDA)-crosslinked polyetherimide(PEI)ultrafiltration membrane as the interlayer,and high-throughput organic solvent nanofiltration membrane(OSN)was prepared by interfacial polymerization and solvent activation *** polyamide(PA)layer surface roughness from 28.4 nm in PA/PEI to 78.3 nm in PA/PDA-HKUST-10.6/PEI membrane,reduced the thickness of the separation layer from 79 to 14 nm,and significantly improved the hydrophilic,thermal and mechanical *** flux of the PA/PDA-HKUST-10.6/PEI membrane in a 0.1 g/L Congo Red(CR)ethanol solution at 0.6 MPa test pressure reached 21.8 L/(m^(2)·hr)and the rejection of CR was 92.8%.Solvent adsorption test,N,N-dimethylformamide(DMF)immersion experiment,and long-term operation test in ethanol showed that the membranes had high solvent *** solvent flux test demonstrated that,under the test pressure of 0.6 MPa,the flux of different solvents ranked as follows:methanol(56.9 L/(m^(2)·hr))>DMF(39.6 L/(m^(2)·hr))>ethanol(31.2 L/(m^(2)·hr))>IPA(4.5 L/(m^(2)·hr))>N-hexane(1.9 L/(m^(2)·hr)).The ability of the membranes to retain dyes in IPA/water dyes solution was also *** flux of the membrane was 30.4 L/(m^(2)·hr)and the rejection of CR was 91.6%when the IPA concentration reached 50%.This OSN membrane-making strategy is economical,environment-friendly and efficient,and has a great application prospect in organic solvent separation systems.

关键词： Interfacial polymerization Organic solvent nanofiltration Interlayer Metal-organic frameworks Polydopamine

NHC-derived carbon-centered luminescent radicals with shortwavelength emission via suppression of Kasha's rule

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Science China Chemistry 2024年第8期67卷 2679-2685页

作者： Can Chen Xin li Xinhua ouyang Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China College of Material Engineering Fujian Agriculture and Forestry University Fuzhou 350108China

Luminescent organic radicals have garnered increasing attention owing to their versatile applications in sensing, imaging, and organic light-emitting diodes(OLEDs), attributed to their unique emission properties originating from the doublet spin ***, the natural narrow bandgap of organic free radicals typically limits their emission to the long-wavelength *** luminescent organic radicals with short-wavelength emission remains a significant challenge. Herein, a series of carbon-centered radicals with short-wavelength emission(383–476 nm) by combining N-heterocyclic carbenes with various polycyclic aromatic hydrocarbons(PAHs)(2-naphthyl, 2a~Ⅰ and 2b~Ⅰ;2-phenanthryl, 2a~Ⅱand 2b~Ⅱ;2-anthryl, 2a~Ⅲand 2b~Ⅲ;3-phenanthryl, 2a~Ⅳand 2b~Ⅳ). Theoretical calculations reveal that the introduction of PAHs significantly increases the ΔE_(D2-D1) in 2a^(Ⅰ–Ⅲ)and 2b^(Ⅰ–Ⅲ)compared to that in phenyl-derived radical congeners. Consequently, the internal transition from D2 to D1 is impeded, leading to a high yield of D2 emission and a suppressed Kasha's rule, thereby overcoming the limitations imposed by their narrow bandgap. For 2a~Ⅳ and 2b~Ⅳ, despite a moderately large ΔED2-D1value, the ΔED3-D1value exceeds 1 e V, indicating that their emission likely originates from the D3 state. Furthermore, we utilized 2a~Ⅲand 2b~Ⅲ as emissive materials in OLEDs,resulting in blue emissions with external quantum efficiencies of 7.5% and 6.5%, respectively.

关键词： N-heterocyclic carbenes luminescent organic molecules carbon-centered radicals short-wavelength emission

高压对β-胡萝卜素分子结构及π-电子离域影响的拉曼光谱研究

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光谱学与光谱分析 2013年第9期33卷 2429-2432页

作者：吴楠楠欧阳顺利里佐威吉林大学物理学院吉林长春130023 内蒙古科技大学稀土学院内蒙古包头014010 内蒙古科技大学内蒙古自治区白云鄂博矿多金属资源综合利用重点实验室内蒙古包头014010

利用金刚石对顶砧在常压至12.85GPa条件下对β-胡萝卜素进行了原位高压拉曼光谱测量,讨论了β-胡萝卜素分子特征峰频率随压力的变化规律及其π-电子离域受压力的影响。实验结果表明,β-胡萝卜素的各特征峰均向高波数移动,其主要的三个... 详细信息

利用金刚石对顶砧在常压至12.85GPa条件下对β-胡萝卜素进行了原位高压拉曼光谱测量,讨论了β-胡萝卜素分子特征峰频率随压力的变化规律及其π-电子离域受压力的影响。实验结果表明,β-胡萝卜素的各特征峰均向高波数移动,其主要的三个特征峰的拉曼频率与压力的关系为:ν1(C-C)=4.74P+1 511.4,ν2(C—C)=2.55P+1 157.6和ν3(CH3)=2.25P+1 011.3,β-胡萝卜素的ν1+ν2和频峰在5.38GPa的压力条件下发生劈裂。对实验结果进一步分析发现随压力增大β-胡萝卜素分子的β环扭转变化使其π-电子离域程度变弱,导致β-胡萝卜素分子主链上的碳碳双键比碳碳单键更容易压缩。

关键词：高压拉曼光谱 β-胡萝卜素 π-电子离域

Hierarchical porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy ceramics prepared by a self-foaming method for thermal insulation

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Journal of Advanced Ceramics 2024年第7期13卷 956-966页

作者： Cuiyan li Ruinan Gao Haibo ouyang Tianzhan Shen Zihao Chen Yanlei li Key Laboratory for Green Manufacturing&Functional Application of Inorganic Materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi’an 710021China

To meet the emerging demands for thermal protection materials for hypersonic aircraft,developing porous ultrahigh-temperature ceramics with both robust mechanical properties and superior thermal insulation performance is a critical ***,we report novel porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy carbide(PHEC)ceramics fabricated by a self-foaming method using commercially available metal chloride and furfuryl alcohol(FA)as *** PHEC ceramics are constructed of microspheres with a size of 2µm,leading to a high porosity of 91.3%and an interconnected *** microspheres consist of high-entropy carbide grains(20 nm),resulting in abundant interfaces and nanosized pores in the PHEC *** to its unique hierarchical structure,the prepared PHEC ceramics have outstanding compressive strength(28.1±2 MPa)and exceptionally low thermal conductivity(κ_(T),0.046 W·m^(-1)·K^(-1))at room *** makes it a promising thermal insulation materials for ultrahigh temperature *** work provides a cost-effective and facile strategy for producing porous ultrahigh-temperature ceramics.

关键词： porous ceramics high-entropy carbides hierarchical structure thermal insulation self-foaming

Charge collection narrowing mechanism in electronic-grade-diamond photodetectors

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Opto-Electronic Advances 2024年第6期7卷 1-3页

作者： Xiaoping ouyang State Key Laboratory of Intense Pulsed Radiation Simulation and Effect and Radiation Detection Research Center Northwest Institute of Nuclear TechnologyXi’an 710024China

Recently,an extreme narrowband spectral response of only 8 nm in electronic-grade diamond-based photodetectors has been observed by Zheng Wei and his colleagues from Sun Yat-sen University for the first time.A charge collection narrowing mechanism assisted by free exciton radiative recombination is proposed,which well reveals the characteristic spectral response of diamond.

关键词： mechanism electronic extreme

Flow Boiling Heat Transfer Characteristics and Delayed Dry-Out Ability of Non-Azeotropic Mixtures R245fa/R134a in Microchannels

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Journal of Thermal Science 2024年第3期33卷 1174-1188页

作者： LU Yongjie liNG Yongjun ZHUANG Yuan li Chenyang ouyang Hongsheng HAN Xiaohong Key Laboratory of Refrigeration and Cryogenic Technology of Zhejiang Province Institute of Refrigeration and CryogenicsZhejiang UniversityHangzhou310007China Zhejiang Zhongguang Electrical Co. Ltd.Lishui323000China State Key Lab for Fluorine Greenhouse Gases Replacement and Control Treatment Zhejiang Research Institute of Chemical IndustryHangzhou310014China

Microchannel flow boiling heat transfer has the advantages of strong heat dissipation capacity,good temperature uniformity,and compact *** is an excellent way to thermally manage electronic devices,but when the heat flux exceeds CHF(Critical Heat Flux),the heat transfer performance deteriorates as the working fluid dries ***-azeotropic mixtures have the potential to effectively delay or avoid dry-out during the boiling process due to their temperature slide characteristics which causes the mass transfer *** understand the influence of non-azeotropic mixtures on microchannel flow boiling,using the phase-change microchannel heat sink as the research object,the experiments on the flow boiling heat transfer performance of R245fa/R134a mixtures under different working conditions were carried out,and the characteristics of flow boiling heat transfer were obtained under the different working conditions,and comparison was developed with those of pure substance *** results demonstrated that a small amount of low-boiling-point components in the high-boiling-point working fluid inhibited boiling heat transfer to some extent,and lowered the average heat transfer coefficient under the non-dryout condition slightly lower than that of the pure substance;however,it also effectively delayed the onset of local dry-out and prevented significant deterioration in thermal transfer performance under the lower mass flow rate and higher heat flux,which could enhance the heat sink's stability.

关键词： microchannel flow boiling non-azeotropic mixture heat transfer characteristics dry-out