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Production of aryl oxygen-containing compounds from catalytic pyrolysis of bagasse lignin over LaTixFe1xO3 被引量:5
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作者 Haiying Wang Hongjing Han +5 位作者 Enhao Sun Yanan Zhang Jinxin Li Yanguang Chen Hua Song Hongzhi Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1939-1944,共6页
A new approach,named production of aryl oxygen-containing compounds from the catalytic pyrolysis of bagasse lignin(BL) over perovskite oxide,was proposed,A series of LaTixFe1-xO3(LTF-x) samples were prepared by the so... A new approach,named production of aryl oxygen-containing compounds from the catalytic pyrolysis of bagasse lignin(BL) over perovskite oxide,was proposed,A series of LaTixFe1-xO3(LTF-x) samples were prepared by the solid state reaction method.The crystal phase and morphology of LTF-x were characterized by XRD and SEM respectively.Catalytic pyrolysis performance of LTF-x was performed by TG-DTG and the distribution patterns of gaseous,liquid and solid products from BL was investigated using a fixed-bed micro-reactor.The optimal reaction conditions were determined:the pyrolysis temperature was 600℃,the mass ratio of mBL:mLTF-0.2 was 3:1,the veloeity of earrier gas was 100 ml·min-1.The gaseous produets were mainly eomposed of CO2,CO,CH4 and CnHm(n=2-4,m=2 n+2 or m=2 n),The main aryl oxygen-containing compounds in liquid products were phenolics,guaiacols,syringols and phenylates,the rest were benzenes,furans,esters and carboxylic acid.The total contents of aryl oxygencontaining compounds were from 62% up to more than 72% under the action of the perovskite.Moreover,the LTF-0.2 sample had nice regenerability. 展开更多
关键词 BAGASSE LIGNIN Perovskite Catalytic pyrolysis ARYL oxygen-containing COMPOUNDS
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Production of aryl oxygen-containing compounds by catalytic pyrolysis of bagasse lignin over LaTi0.2Fe0.8O3 prepared by different methods 被引量:6
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作者 Haiying Wang Hongjing Han +6 位作者 Enhao Sun Yanan Zhang Jinxin Li Yanguang Chen Hua Song Hongzhi Zhao Yue Kang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第1期76-83,共8页
To realize the resource and high-value utilization,a new approach,named bagasse lignin(BL) used to produce aryl oxygen-containing compounds by catalytic pyrolysis over perovskite,was proposed,LaTi0.2Fe0.8O3(LTF) sampl... To realize the resource and high-value utilization,a new approach,named bagasse lignin(BL) used to produce aryl oxygen-containing compounds by catalytic pyrolysis over perovskite,was proposed,LaTi0.2Fe0.8O3(LTF) samples prepared by the sol-gel method(SG) and the solid-state reaction method(SS)were characterized.The catalytic action on BL pyrolysis was performed by the test of TG-DTG and the evaluation of the fixed bed micro-reactor,the components and contents of the products were determined.The results show that LTF samples have cubic perovskite phase,LTF prepared by SG(LTF-SG) is porous with larger specific surface area than LTF prepared by SS(LTF-SS).During the pyrolysis of BL,the addition of LTF lowers the pyrolysis temperature and the activation energy,the contents of CO2 and CO in gaseous products reduce by 4.6%-8.0% and 30.7%-34.3%,respectively,the total content of aryl oxygencontaining compounds(including phenolics,guaiacols,syringols and phenylates) in liquid products increases from 62 wt% to more than 72 wt%,and LTF-SG shows better catalytic performance.LTF samples have nice phase and catalytic stabilities for BL pyrolysis after five successive redox cycles. 展开更多
关键词 Bagasse lignin Perovskite Catalytic pyrolysis Aryl oxygen-containing compounds Titanium-substituted lanthanum ferrite Rare earths
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Adsorption of cadmium ions from aqueous solutions by activated carbon with oxygen-containing functional groups 被引量:5
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作者 边宇 卞兆勇 +4 位作者 张俊宵 丁爱中 刘少蕾 郑蕾 王辉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第10期1705-1711,共7页
The adsorption of aqueous cadmium ions(Cd(Ⅱ)) have been investigated for modified activated carbon(AC-T)with oxygen-containing functional groups.The oxygen-containing groups of AC-T play an important role in Cd(Ⅱ) i... The adsorption of aqueous cadmium ions(Cd(Ⅱ)) have been investigated for modified activated carbon(AC-T)with oxygen-containing functional groups.The oxygen-containing groups of AC-T play an important role in Cd(Ⅱ) ion adsorption onto AC-T.The modified activated carbon is characterized by scanning electron microscopy,Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS).The results of batch experiments indicate that the maximal adsorption could be achieved over the broad pH range of 4.5 to 6.5.Adsorption isotherms and kinetic study suggest that the sorption of Cd(Ⅱ) onto AC-T produces monolayer coverage and that adsorption is controlled by chemical adsorption.And the adsorbent has a good reusability.According to the FT-IR and XPS analyses,electrostatic attraction and cation exchange between Cd(Ⅱ) and oxygen-containing functional groups on AC-T are dominant mechanisms for Cd(Ⅱ) adsorption. 展开更多
关键词 Activated carbon oxygen-containing functional groups Cd(II) Adsorption mechanism
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Structural Characterization and Octanol/water Partition Coefficients(LogP) Prediction for Oxygen-containing Organic Compounds 被引量:8
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作者 廖立敏 黄茜 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1243-1250,共8页
New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed t... New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed to build two relationship models between the structures and octanol/water partition coefficients(LogP) of the compounds. The modeling correlation coefficients(R) were 0.976 and 0.922, and the "leave one out" cross validation correlation coefficients(R(CV)) were 0.973 and 0.909, respectively. The results showed that the structural descriptors could well characterize the molecular structures of the compounds; the stability and predictive power of the models were good. 展开更多
关键词 oxygen-containing organic compounds octanol/water partition coefficients(LogP) structural descriptors relationship between structures and properties
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Predominating stable adsorption and direct electrochemistry of glucose oxidase on carbon nanotubes by oxygen-containing groups 被引量:1
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作者 Chun Hai Yang Cheng Guo Hu Sheng Shui Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第3期313-315,共3页
Stable adsorption and direct electrochemistry of glucose oxidase (COx) occurred on nitric acid (HNO3)-treated multi-walled carbon nanotubcs (MWNTs) instead of as-received MWNTs, demonstrating the critical roles ... Stable adsorption and direct electrochemistry of glucose oxidase (COx) occurred on nitric acid (HNO3)-treated multi-walled carbon nanotubcs (MWNTs) instead of as-received MWNTs, demonstrating the critical roles of oxygen-containing groups in stable adsorption and direct electrochemistry of GOx on carbon nanotubcs (CNTs). 展开更多
关键词 Glucose oxidase ADSORPTION Direct electrochemistry Carbon nanotubes oxygen-containing groups
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Modeling Gas Chromatographic Retention Indices of Oxygen-containing Compounds by Novel Atom-type Topological Indices 被引量:1
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作者 Xiao-fang Hu Chun-hui Lu Chun-sheng Yin 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第3期243-247,共5页
Quantitative structure-retention relationship (QSRR) model for the estimation of retention indices (RIs) of 39 oxygen-containing compounds containing ketones and esters was established by our newly introduced dist... Quantitative structure-retention relationship (QSRR) model for the estimation of retention indices (RIs) of 39 oxygen-containing compounds containing ketones and esters was established by our newly introduced distance-based atom-type indices DAI. The useful application of the novel DAI indices has been demonstrated by developing accurate predictive equations for gas chromatographic retention indices. The statistical results of the multiple linear regression for the final model are τ=0.9973 and s=8.23. Furthermore, an external test set of 10 oxo-containing compounds can be accurately predicted with the final equation giving the following statistical results: τpred:0.9966 and spred=8.56. 展开更多
关键词 Topological indices Retention indices oxygen-containing compounds
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Oxygen-Containing Functional Groups Regulating the Carbon/Electrolyte Interfacial Properties Toward Enhanced K^(+)Storage 被引量:2
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作者 Yufan Peng Zhen Chen +7 位作者 Rui Zhang Wang Zhou Peng Gao Jianfang Wu Hui Liu Jilei Liu Aiping Hu Xiaohua Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第12期29-43,共15页
Oxygen-containing functional groups were found to e ectively boost the K^(+)storage performance of carbonaceous materials,however,the mechanism behind the performance enhancement remains unclear.Herein,we report highe... Oxygen-containing functional groups were found to e ectively boost the K^(+)storage performance of carbonaceous materials,however,the mechanism behind the performance enhancement remains unclear.Herein,we report higher rate capability and better long-term cycle performance employing oxygen-doped graphite oxide(GO)as the anode material for potassium ion batteries(PIBs),compared to the raw graphite.The in situ Raman spectroscopy elucidates the adsorption-intercalation hybrid K^(+)storage mechanism,assigning the capacity enhancement to be mainly correlated with reversible K^(+)adsorption/desorption at the newly introduced oxygen sites.It is unraveled that the C=O and COOH rather than C-O-C and OH groups contribute to the capacity enhancement.Based on in situ Fourier transform infrared(FT-IR)spectra and in situ electrochemical impedance spectroscopy(EIS),it is found that the oxygen-containing functional groups regulate the components of solid electrolyte interphase(SEI),leading to the formation of highly conductive,intact and robust SEI.Through the systematic investigations,we hereby uncover the K^(+)storage mechanism of GO-based PIB,and establish a clear relationship between the types/contents of oxygen functional groups and the regulated composition of SEI. 展开更多
关键词 oxygen-containing functional groups Solid electrolyte interphase In situ spectroscopic characterization Potassium ion batteries
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A REVIEW OF OXYGEN-CONTAINING SURFACE GROUPS AND SURFACE MODIFICATION OF ACTIVATED CARBON 被引量:1
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作者 WUYongwen LIZhong +1 位作者 XIHongxia XIAQibin 《Chinese Journal of Reactive Polymers》 2004年第1期89-96,共8页
This review focused on the recent reports related to the function, characterization and modification of oxygen-containing surface groups of activated carbon (AC). The Oxygen-containing surface groups were briefly desc... This review focused on the recent reports related to the function, characterization and modification of oxygen-containing surface groups of activated carbon (AC). The Oxygen-containing surface groups were briefly described, and the most frequently used techniques for characterization of the oxygen-containing surface groups on ACs were also briefly stated. A detailed discussion of the effects of the oxygen-containing surface groups on the adsorptive capacity of AC was given. The recent progresses in modification of the oxygen-containing surface groups of AC were also reviewed. 展开更多
关键词 oxygen-containing group Activated carbon Surface chemistry Modification.
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Study on the Formation Mechanism of Oxygen-containing Groups on the Surfaces of Hypercrosslinked Polystyrenes
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作者 Guan Hua MENG Ai Min LI +2 位作者 Lin WU Fu Qiang LIU Quan Xing ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期121-124,共4页
The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to charact... The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to characterize the surface chemistry of the synthesized polymers. The GC-MS was applied to analyze nitrobenzene which was the solvent in the reaction. The functionalities such as carbonyls and phenols were formed through the oxidation of residual chloromethyl groups by nitrobenzene and the carboxylic groups were formed through further oxidation by oxygen. The nitrobenzene was deoxidized to nitrosobenzene and further to aniline. 展开更多
关键词 SYNTHESIS oxygen-containing groups mechanism.
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A novel approach to synthesize porous graphene by the transformation and deoxidation of oxygen-containing functional groups
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作者 Da Zhang Luming Chen +6 位作者 Yaochun Yao Feng Liang Tao Qu Wenhui Ma Bing Yang Yongnian Dai Yong Lei 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第12期2313-2317,共5页
In this study,impurity-free porous graphene(PG) with intrinsic pore structure was synthesized through a facile acid-alkali etching-assisted sonication approach.The pore structure appears on the surface of graphene she... In this study,impurity-free porous graphene(PG) with intrinsic pore structure was synthesized through a facile acid-alkali etching-assisted sonication approach.The pore structure appears on the surface of graphene sheets due to intrinsic defects of graphene.The PG possessed an extremely high specific surface area of 2184 m^2/g,the size of^5 μm and layer numbers of 3-8.Additionally,PG contained micropores and mesopores simultaneously,with an average pore diameter of approximately 3 nm.The effects of acid,alkali,and ultrasound treatment on PG preparation were elucidated by transmission electron microscopy and fourier transform infrared spectroscopy.First,in an acidic solution,oxygen-containing functional groups(hydroxyls,carboxyl,and epoxides) were formed due to the hydrolysis of sulfate and continuous transformations of these functional groups on graphene oxide.Second,under the synergistic effects of alkali and ultrasound treatment,PG was obtained due to the loss of carboxyl and epoxide groups.A new route for preparing PG was provided by the proposed method. 展开更多
关键词 HYDROLYSIS DEOXIDATION Ultrasound oxygen-containing functional group Porous graphene
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PHASES评分预测颅内动脉瘤破裂出血研究进展
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作者 白春杰 李淑芝 +2 位作者 张晓梅 焦娇 刘文辉 《中国医药指南》 2025年第28期41-44,共4页
颅内动脉瘤(IA)是一种常见的脑血管疾病,临床多采取介入治疗、显微外科手术夹闭治疗和联合治疗。据统计,颅内动脉瘤在全球成年人中的总体发病率为3.20%,破裂率在1%~2%。颅内动脉瘤破裂后果极其严重,具有极高的致残、致死率。研究报道PHA... 颅内动脉瘤(IA)是一种常见的脑血管疾病,临床多采取介入治疗、显微外科手术夹闭治疗和联合治疗。据统计,颅内动脉瘤在全球成年人中的总体发病率为3.20%,破裂率在1%~2%。颅内动脉瘤破裂后果极其严重,具有极高的致残、致死率。研究报道PHASES评分有助于临床颅内动脉瘤患者风险分层和未破裂颅内动脉瘤(UIA)管理,本文介绍了PHASES评分的构建,梳理了PHASES评分应用于颅内动脉瘤患者风险评估的国内外现状。风险预测可帮助临床医师识别高风险个体,进而实现精准预防,提高医疗质量和治疗效率,减少医疗资源的消耗,减轻财政负担等。故本研究旨在对PHASES评分进行综述,为医疗工作者早期识别颅内动脉瘤患者破裂风险、临床患者治疗方案的制订及管理、开展精准个性化干预措施等提供借鉴与参考。 展开更多
关键词 颅内动脉瘤 风险预测 phaseS评分
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Pharmacological intervention for chronic phase of spinal cord injury 被引量:1
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作者 Chihiro Tohda 《Neural Regeneration Research》 SCIE CAS 2025年第5期1377-1389,共13页
Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challengin... Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challenging issues in spinal cord injury. As spinal cord injury progresses to the chronic phase, lost motor and sensory functions are not recovered. Several reasons may be attributed to the failure of recovery from chronic spinal cord injury. These include factors that inhibit axonal growth such as activated astrocytes, chondroitin sulfate proteoglycan, myelin-associated proteins, inflammatory microglia, and fibroblasts that accumulate at lesion sites. Skeletal muscle atrophy due to denervation is another chronic and detrimental spinal cord injury–specific condition. Although several intervention strategies based on multiple outlooks have been attempted for treating spinal cord injury, few approaches have been successful. To treat chronic spinal cord injury, neural cells or tissue substitutes may need to be supplied in the cavity area to enable possible axonal growth. Additionally, stimulating axonal growth activity by extrinsic factors is extremely important and essential for maintaining the remaining host neurons and transplanted neurons. This review focuses on pharmacotherapeutic approaches using small compounds and proteins to enable axonal growth in chronic spinal cord injury. This review presents some of these candidates that have shown promising outcomes in basic research(in vivo animal studies) and clinical trials: AA-NgR(310)ecto-Fc(AXER-204), fasudil, phosphatase and tensin homolog protein antagonist peptide 4, chondroitinase ABC, intracellular sigma peptide,(-)-epigallocatechin gallate, matrine, acteoside, pyrvate kinase M2, diosgenin, granulocyte-colony stimulating factor, and fampridine-sustained release. Although the current situation suggests that drug-based therapies to recover function in chronic spinal cord injury are limited, potential candidates have been identified through basic research, and these candidates may be subjects of clinical studies in the future. Moreover, cocktail therapy comprising drugs with varied underlying mechanisms may be effective in treating the refractory status of chronic spinal cord injury. 展开更多
关键词 axonal growth chronic phase clinical study PHARMACOTHERAPY spinal cord injury
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Phase distortion correction of fringe patterns in spaceborne Doppler asymmetric spatial heterodyne interferometry 被引量:1
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作者 PEI Hui-yi JIANG Lun +4 位作者 WANG Jin-jiang CUI Yong FANG Yuan-xiang ZHANG Jia-ming CHEN Ci 《中国光学(中英文)》 北大核心 2025年第2期382-392,共11页
As an advanced device for observing atmospheric winds,the spaceborne Doppler Asymmetric Spatial Heterodyne(DASH)interferometer also encounters challenges associated with phase distortion,par-ticularly in limb sounding... As an advanced device for observing atmospheric winds,the spaceborne Doppler Asymmetric Spatial Heterodyne(DASH)interferometer also encounters challenges associated with phase distortion,par-ticularly in limb sounding scenarios.This paper discusses interferogram modeling and phase distortion cor-rection techniques for spaceborne DASH interferometers.The modeling of phase distortion interferograms with and without Doppler shift for limb observation was conducted,and the effectiveness of the analytical expression was verified through numerical simulation.The simulation results indicate that errors propagate layer by layer while using the onion-peeling inversion algorithm to handle phase-distorted interferograms.In contrast,the phase distortion correction algorithm can achieve effective correction.This phase correction method can be successfully applied to correct phase distortions in the interferograms of the spaceborne DASH interferometer,providing a feasible solution to enhance its measurement accuracy. 展开更多
关键词 Doppler asymmetric spatial heterodyne spectroscopy phase distortion phase inversion atmospheric wind measurement
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption 被引量:1
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
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Spin-dependent amplitude and phase modulation with multifold interferences via single-layer diatomic all-silicon metasurfaces 被引量:2
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作者 Hui Li Chenhui Zhao +6 位作者 Jie Li Hang Xu Wenhui Xu Qi Tan Chunyu Song Yun Shen Jianquan Yao 《Opto-Electronic Science》 2025年第3期2-15,共14页
Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarizat... Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection. 展开更多
关键词 diatomic metasurface geometric phase complex amplitude modulation spin-selective
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Interaction between dynamic recrystallization and phase transformation of Ti-43Al-4Nb-1Mo-0.2B alloy during hot deformation 被引量:2
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作者 Xiaofei Chen Bin Tang +5 位作者 Beibei Wei Wenxin Xu Biao Ma Jinhua Dai Guoming Zheng Jinshan Li 《Journal of Materials Science & Technology》 2025年第11期130-142,共13页
Theβsolidifiedγ-TiAl alloy holds important application value in the aerospace industry,while its com-plex phase compositions and geometric structures pose challenges to its microstructure control during the thermal-... Theβsolidifiedγ-TiAl alloy holds important application value in the aerospace industry,while its com-plex phase compositions and geometric structures pose challenges to its microstructure control during the thermal-mechanical process.The microstructure evolution of Ti-43Al-4Nb-1Mo-0.2B alloy at 1200℃/0.01 s−1 was investigated to clarify the coupling role of dynamic recrystallization(DRX)and phase transformation.The results revealed that the rate of DRX inα2+γlamellar colonies was comparatively slower than that inβo+γmixed structure,instead being accompanied by intense lamellar kinking and rotation.The initiation and development rates of DRX inα2,βo,andγphases decreased sequentially.The asynchronous DRX of the various geometric structures and phase compositions resulted in the un-even deformed microstructure,and the dynamic softening induced by lamellar kinking and rotation was replaced by strengthened DRX as strain increased.Additionally,the blockyα2 phase and the terminals ofα2 lamellae were the preferential DRX sites owing to the abundant activated slip systems.Theα2→βo transformation within lamellar colonies facilitated DRX and fragment ofα2 lamellae,while theα2→γtransformation promoted the decomposition ofα2 lamellae and DRX ofγlamellae.Moreover,the var-iedβo+γmixed structures underwent complicated evolution:(1)Theγ→βo transformation occurred at boundaries of lamellar colonies,followed by simultaneous DRX ofγlamellar terminals and neighboringβo phase;(2)DRX occurred earlier within the band-likeβo phase,with the delayed DRX in enclosedγphase;(3)DRX within theβo synapses and neighboringγphase was accelerated owing to generation of elastic stress field;(4)Dispersedβo particles triggered particle stimulated nucleation(PSN)ofγphase.Eventually,atomic diffusion along crystal defects inβo andγphases caused fracture of band-likeβo phase and formation of massiveβo particles,impeding grain boundary migration and hindering DRXed grain growth ofγphase. 展开更多
关键词 TiAl alloy Hot deformation Dynamic recrystallization phase transformation
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High-burn-up structure evolution in polycrystalline UO_(2):Phase-field modeling investigation 被引量:2
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作者 Dan Sun Yanbo Jiang +4 位作者 Chuanbao Tang Yong Xin Zhipeng Sun Wenbo Liu Yuanming Li 《Chinese Physics B》 2025年第2期378-386,共9页
Understanding the evolution of microstructures in nuclear fuels under high-burn-up conditions is critical for extending fuel refueling cycles and enhancing nuclear reactor safety.In this study,a phase-field model is p... Understanding the evolution of microstructures in nuclear fuels under high-burn-up conditions is critical for extending fuel refueling cycles and enhancing nuclear reactor safety.In this study,a phase-field model is proposed to examine the evolution of high-burn-up structures in polycrystalline UO_(2).The formation and growth of recrystallized grains were initially investigated.It was demonstrated that recrystallization kinetics adhere to the Kolmogorov–Johnson–Mehl–Avrami(KJMA)equation,and that recrystallization represents a process of free-energy reduction.Subsequently,the microstructural evolution in UO_(2) was analyzed as the burn up increased.Gas bubbles acted as additional nucleation sites,thereby augmenting the recrystallization kinetics,whereas the presence of recrystallized grains accelerated bubble growth by increasing the number of grain boundaries.The observed variations in the recrystallization kinetics and porosity with burn-up closely align with experimental findings.Furthermore,the influence of grain size on microstructure evolution was investigated.Larger grain sizes were found to decrease porosity and the occurrence of high-burn-up structures. 展开更多
关键词 high-burn-up structure phase field uranium dioxide gas bubble RECRYSTALLIZATION
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Exploring the Scientific Connotation of Gypsum in Baihu Decoction Compatibility with Heat-clearing Effect Based on Phase Composition 被引量:2
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作者 Yunyun Wang Zhengxian Zhang +2 位作者 Haotian Peng Huahui Zeng Xiangxiang Wu 《Chinese Medicine and Natural Products》 2025年第1期35-46,共12页
Objective This study aimed to study the effects of different crystalline states of Sheng Shigao(raw gypsum,RG)and its inorganic elements on the antipyretic efficacy of Baihu Decoction(BHT).Methods RG samples calcined ... Objective This study aimed to study the effects of different crystalline states of Sheng Shigao(raw gypsum,RG)and its inorganic elements on the antipyretic efficacy of Baihu Decoction(BHT).Methods RG samples calcined at different temperatures were prepared.The phase composition of RG and Duan Shigao(calcination of gypsum,CG)as well as the changes in phase composition before and after adding water to RG calcined at specific temperatures,were determined using X-ray diffraction(XRD).A fever model was established by subcutaneously injecting 20%yeast suspension(10 mL·kg~(-1))into the backs of rats.The effects of BHT containing RG in different crystalline states on rat body temperature were measured.Serum levels of IL-1β,IL-6,and hypothalamic prostaglandin E2(PGE_2)were detected using ELISA.Serum Ca~(2+)levels were measured using a microplate method.The content of trace elements in RG and CG and the corresponding freeze-dried BHT powder was determined using inductively coupled plasma mass spectrometry(ICP-MS).The complexation of representative inorganic elements with mangiferin,a major active component in BHT,was investigated using UV-Vis spectroscopy and fluorescence spectroscopy.A validation model was established using RAW264.7 mouse macrophages.Drug-containing serum of BHT with different inorganic elements was prepared,and the nitric oxide(NO)levels in the cell supernatant of different treatment groups were measured using the Griess method.The mRNA levels of IL-6,TNF-α,and PGE2in each group were detected using qPCR(real-time fluorescent quantitative PCR).Results After calcination,the phase composition of RG changed,and the content of inorganic elements in RG,CG170(RG calcined at 170°C),and CG350(RG calcined at 350°C)showed similar trends.Compared with RG,the content of Ca,Sr,Al,and Na in CG changed significantly.Compared with BHT,the content of Ca,Sr,Si,and Na in CG changed significantly when incorporated into the formula.Intermolecular interactions confirmed strong binding between mangiferin and Cu~(2+)and Al~(3+).Cu~(2+)and Fe~(3+)exhibited fluorescence quenching effects on mangiferin solution,while Al~(3+)and Zn~(2+)showed strong fluorescence enhancement,with fluorescence intensity increasing by 120-fold and 30-fold,respectively.In vitro evaluation of synergistic anti-inflammatory effects confirmed that Ca,Fe,Cr,Al,and Si exhibited synergistic anti-inflammatory effects.Conclusion The crystalline state of RG has little effect on its antipyretic properties,while Ca,Sr,Na,Fe,and Al are likely the key material bases influencing its efficacy. 展开更多
关键词 GYPSUM Baihu Decoction heat-clearing compatibility of medicines phase composition
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Carbon-based porous materials for performance-enhanced composite phase change materials in thermal energy storage:Materials,fabrication and applications 被引量:5
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作者 Lei Hu Li Zhang +4 位作者 Wei Cui Qinyou An Ting Ma Qiuwang Wang Liqiang Mai 《Journal of Materials Science & Technology》 2025年第7期204-226,共23页
Latent heat thermal energy storage(TES)effectively reduces the mismatch between energy supply and demand of renewable energy sources by the utilization of phase change materials(PCMs).However,the low thermal conductiv... Latent heat thermal energy storage(TES)effectively reduces the mismatch between energy supply and demand of renewable energy sources by the utilization of phase change materials(PCMs).However,the low thermal conductivity and poor shape stability are the main drawbacks in realizing the large-scale application of PCMs.Promisingly,developing composite PCM(CPCM)based on porous supporting mate-rial provides a desirable solution to obtain performance-enhanced PCMs with improved effective thermal conductivity and shape stability.Among all the porous matrixes as supports for PCM,three-dimensional carbon-based porous supporting material has attracted considerable attention ascribing to its high ther-mal conductivity,desirable loading capacity of PCMs,and excellent chemical compatibility with various PCMs.Therefore,this work systemically reviews the CPCMs with three-dimensional carbon-based porous supporting materials.First,a concise rule for the fabrication of CPCMs is illustrated in detail.Next,the experimental and computational research of carbon nanotube-based support,graphene-based support,graphite-based support and amorphous carbon-based support are reviewed.Then,the applications of the shape-stabilized CPCMs including thermal management and thermal conversion are illustrated.Last but not least,the challenges and prospects of the CPCMs are discussed.To conclude,introducing carbon-based porous materials can solve the liquid leakage issue and essentially improve the thermal conductivity of PCMs.However,there is still a long way to further develop a desirable CPCM with higher latent heat capacity,higher thermal conductivity,and more excellent shape stability. 展开更多
关键词 Thermal energy storage phase change material Supporting material Carbon-based material Thermal conductivity Shape-stabilized composite
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Accurate prediction of magnetocaloric effect in NiMn-based Heusler alloys by prioritizing phase transitions through explainable machine learning 被引量:2
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作者 Yi-Chuan Tang Kai-Yan Cao +7 位作者 Ruo-Nan Ma Jia-Bin Wang Yin Zhang Dong-Yan Zhang Chao Zhou Fang-Hua Tian Min-Xia Fang Sen Yang 《Rare Metals》 2025年第1期639-651,共13页
With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase t... With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase transitions into account,and as a result,the predictions are usually not accurate enough.In this context,we have established an explicable relationship between alloy compositions and phase transition by feature imputation.A facile machine learning is proposed to screen candidate NiMn-based Heusler alloys with desired magnetic entropy change and magnetic transition temperature with a high accuracy R^(2)≈0.98.As expected,the measured properties of prepared NiMn-based alloys,including phase transition type,magnetic entropy changes and transition temperature,are all in good agreement with the ML predictions.As well as being the first to demonstrate an explicable relationship between alloy compositions,phase transitions and magnetocaloric properties,our proposed ML model is highly predictive and interpretable,which can provide a strong theoretical foundation for identifying high-performance magnetocaloric materials in the future. 展开更多
关键词 NiMn-based Heusler materials phase transition-type Machine learning Magnetocaloric effect Composition design
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