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Configuring single-layer MXene nanosheet onto natural wood fiber via C-Ti-C covalent bonds for high-stability Li-S batteries
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作者 Yangyang Chen Yu Liao +5 位作者 Ying Wu Lei Li Zhen Zhang Sha Luo Yiqiang Wu Yan Qing 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期701-711,I0016,共12页
Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness.However,the low conductivity and ... Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness.However,the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of LSBs.Herein,in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber(MX/PCWF)composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas diffusion.The unique architecture,wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls,ensures rapid polysulfide conversion and continuous electron transfer for redox reactions.The C-Ti-C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides,effectively suppressing the shuttle effect.An impressive capacity of 1301.1 m A h g^(-1)at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host,as evidenced by the capacity maintenance of 722.6 m A h g^(-1)after 500 cycles.Notably,the MX/PCWF/S cathode can still deliver a high capacity of 886.8 m A h g^(-1)at a high S loading of 5.6 mg cm^(-2).The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries. 展开更多
关键词 Lithium-sulfur batteries s cathodes MXene nanosheets wood fiber C-Ti-C bonds
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Experimental study on full scale light frame wood house under repeated lateral load
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作者 陈松来 王焕定 +1 位作者 樊承谋 潘景龙 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第3期125-130,共6页
In order to obtain a deeper understanding of the behavior of the structure under high wind load,this paper conducted an experimental study on a full-scale L-shaped single story light frame wood house under the uniform... In order to obtain a deeper understanding of the behavior of the structure under high wind load,this paper conducted an experimental study on a full-scale L-shaped single story light frame wood house under the uniform lateral load simulated using a gasbag.The investigation involved the performance of light frame wood structure after it experienced the repeated cyclic lateral wind load as well as the performance of the structure under the ultimate lateral load.Then,the study verified that light frame wood structure can resist repeated cyclic wind loads without observable degradation in stiffness during the anticipated serve life,and recommended shear wall percent drift restriction for lateral wind load design of wood structure in serviceability limit states is 1/400 drift,and in ultimate limit states is 1/80 drift.The conclusions of this paper can be benefit for the engineering practice of the light frame wood structures in high wind load regions. 展开更多
关键词 light frame wood house simulated lateral wind load full scale test percent drift restriction
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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases
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作者 Lifang Zhao Mingkai Zhang +4 位作者 Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai 《Neural Regeneration Research》 SCIE CAS 2025年第8期2373-2381,共9页
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k... Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results. 展开更多
关键词 Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein NEURODEGENERATION neurofilament light chain plasma biomarkers single molecule array storage time tau
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Automobile light control system based on CAN bus and contactless switch 被引量:1
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作者 何立仁 王义 《Journal of Measurement Science and Instrumentation》 CAS 2014年第1期66-70,共5页
In order to solve the complex wiring and low reliability of conventional light control system,an automobile contactless switch light system is designed combined with Hall element and controller area network (CAN) bu... In order to solve the complex wiring and low reliability of conventional light control system,an automobile contactless switch light system is designed combined with Hall element and controller area network (CAN) bus technology.The processing system of electromagnetic compatibility controlled by CAN bus is improved to reduce the electromagnetic interference from the controller and other sources of interference.With Freescale's high-performance single-chip MC9S08DZ60 and CAN transceiver TJA1050,the overall circuit design and software design are presented.The test results show that the designed light control system is feasible. 展开更多
关键词 light control system CAN bus MC9s08DZ60 Hall element
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运用Light’s标准评定心力衰竭性胸腔积液性质结果分析
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作者 杜桂英 张维录 +2 位作者 周鹏 贾文静 王桂霞 《山东医药》 CAS 北大核心 2004年第13期45-46,共2页
关键词 light’s标准 评定 心力衰竭 胸腔积液
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Structure, photocatalytic and antibacterial activity study of Meso porous Ni and S co-doped TiO2 nano material under visible light irradiation 被引量:3
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作者 K.V.Divya Lakshmi T.Siva Rao +2 位作者 J.Swathi Padmaja I.Manga Raju M.Ravi Kumar 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第7期1630-1641,共12页
Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic an... Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical techniques.The characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and EDX.These results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation. 展开更多
关键词 sol–gel Ni–s CO-DOPED TIO2 Photocatalysis under visible light Degradation of Bismarck BROWN Red Antibacterial activity
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Correction Method of Light Hydrocarbons Losing and Heavy Hydrocarbon Handling for Residual Hydrocarbon (S_1) from Shale 被引量:6
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作者 WANG Min TIAN Shansi +3 位作者 CHEN Guohui XUE Haitao HUANG Aihua WANG Wenguang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1792-1797,共6页
In China, hot researches on shale oil were raised by the important breakthrough of shale oil in America. Obviously, the first important issue is the actual shale oil resource potential of China, and the selection of t... In China, hot researches on shale oil were raised by the important breakthrough of shale oil in America. Obviously, the first important issue is the actual shale oil resource potential of China, and the selection of the key appraisement parameter is vital to the shale oil resource amount. Among the appraisement parameters, the oil content parameter(S1) is the key one, but the evaluation result is generally lower because of light hydrocarbon losing and heavy hydrocarbon handling. And the more important thing is that the light hydrocarbon with small molecular weight is more recoverable, and therefore its amount is important to the total shale oil yields. Based on pyrolysis experiments and the kinetic model of hydrocarbon generation, correction factors and a model of light hydrocarbon losing and heavy hydrocarbon handling were established. The results show that the correction factor of heavy hydrocarbon handling is 3.2, and that of light hydrocarbon losing is controlled by kerogen type, maturity and hydrocarbon generation environment(closed or open). 展开更多
关键词 oil content s1 shale oil light hydrocarbons losing heavy hydrocarbon handling
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Synthesis of Ag/AgCl/Fe-S plasmonic catalyst for bisphenol A degradation in heterogeneous photo-Fenton system under visible light irradiation 被引量:11
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作者 Yun Liu Yanyan Mao +3 位作者 Xiaoxiao Tang Yin Xu Chengcheng Li Feng Li 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第10期1726-1735,共10页
A novel plasmonic photo‐Fenton catalyst of Ag/AgCl/Fe‐S was synthesized by ion exchange and photoreduction methods.The obtained catalyst was characterized by X‐ray diffraction,X‐ray photoelectron spectroscopy,scan... A novel plasmonic photo‐Fenton catalyst of Ag/AgCl/Fe‐S was synthesized by ion exchange and photoreduction methods.The obtained catalyst was characterized by X‐ray diffraction,X‐ray photoelectron spectroscopy,scanning electron microscope imaging,and Brunauer‐Emmett‐Teller measurements.Moreover,the photocatalytic activity of Ag/AgCl/Fe‐S was investigated for its degradation activity towards bisphenol A(BPA)as target pollutant under visible light irradiation.The effects of H2O2concentration,pH value,illumination intensity,and catalyst dosage on BPA degradation were examined.Our results indicated that the Ag/AgCl material was successfully loaded onto Fe‐sepiolite and showed a high photocatalytic activity under illumination by visible light.Furthermore,active species capture experiments were performed to explore the photocatalytic mechanism of the Ag/AgCl/Fe‐S in this heterogeneous photo‐Fenton process,where the major active species included hydroxyl radicals(?OH)and holes(h+). 展开更多
关键词 Visible light Photo‐Fenton Plasmonic catalyst Ag/AgCl/Fe‐s sEPIOLITE
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Preliminary research on myosin light chain kinase in rabbit liver 被引量:6
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作者 Bin Ren~1 Hua-Qing Zhu~2 Zhao-Feng Luo~1 Qing Zhou~2 Yuan Wang~2 Yu-Zhen Wang~1 1 Department of Biochemistry and Molecular Biology,University of Science and Technology of China,Hefei 230027,Anhui Province,China2 Laboratory of Molecular Biology,Anhui Medical University,Hefei 230032,Anhui Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期868-871,共4页
AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver. METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction(RT-PCR); the MLCK was obt... AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver. METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction(RT-PCR); the MLCK was obtained from rabbit liver, and its activity was analyzed by gamma-(32)P incorporation technique to detect the phosphorylation of myosin light chain. RESULTS: MLCK was expressed in rabbit liver, and the activity of the enzyme was similar to rabbit smooth muscle MLCK, and calmodulin-dependent. When the concentration was 0.65 mg x L(-1), the activity was at the highest level. CONCLUSION: MLCK expressed in rabbit liver may catalyze the phosphorylation of myosin light chain, which may play important roles in the regulation of hepatic cell functions. 展开更多
关键词 ANIMALs HEPATOCYTEs Liver Myosin light Chains Myosin-light-Chain Kinase PHOsPHORYLATION RABBITs Research support Non-U.s. Gov't
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A Novel Sr_2CuInO_3S p-type semiconductor photocatalyst for hydrogen production under visible light irradiation 被引量:3
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作者 Yushuai Jia Jingxiu Yang +2 位作者 Dan Zhao Hongxian Han Can Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第4期420-426,共7页
A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type sem... A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations (DFT) and electrochem ical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3S photocatalyst has appreciate conduction and valence band positions for hydrogen and oxygen evolution, respectively. Photocat alytic hydrogen production experiments under a visible light irradiation (A〉420 nm) were carried out by loading different metal and metal-like cocatalysts on Sr2CuInO3S and Rh was found to be the best one among the tested ones. 展开更多
关键词 hydrogen production PHOTOCATALYsT p-type semiconductor sr2CuIn03s oxysulfide visible light COCATALYsT
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Construction of 2D Zn‐MOF/BiVO_(4)S‐scheme heterojunction for efficient photocatalytic CO_(2) conversion under visible light irradiation 被引量:6
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作者 Zhenlong Zhao Ji Bian +6 位作者 Lina Zhao Hongjun Wu Shuai Xu Lei Sun Zhijun Li Ziqing Zhang Liqiang Jing 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1331-1340,共10页
The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to ... The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to efficient charge transfer,the abundance of catalytic sites,and extended light absorption.Herein,an S‐scheme heterojunction of 2D/2D zinc porphyrin‐based metal‐organic frameworks/BiVO_(4)nanosheets(Zn‐MOF/BVON)was fabricated for efficient photocatalytic CO_(2)conversion.The optimal one shows a 22‐fold photoactivity enhancement when compared to the previously reported BiVO4 nanoflake(ca.15 nm),and even exhibits~2‐time improvement than the traditional g‐C3N4/BiVO4 heterojunction.The excellent photoactivities are ascribed to the strengthened S‐scheme charge transfer and separation,promoted CO_(2)activation by the well‐dispersed metal nodes Zn_(2)(COO)_(4)in the Zn‐MOF,and extended visible light response range based on the results of the electrochemical reduction,electron paramagnetic resonance,and in‐situ diffuse reflectance infrared Fourier transform spectroscopy.The dimension‐matched Zn‐MOF/BVON S‐scheme heterojunction endowed with highly efficient charge separation and abundant catalytic active sites contributed to the superior CO2 conversion.This study offers a facile strategy for constructing S‐scheme heterojunctions involving porphyrin‐based MOFs for solar fuel production. 展开更多
关键词 BiVO4 nanosheet 2D zinc porphyrin‐based MOFs modification sscheme heterojunction Visible light catalysis CO_(2) conversion
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Preparation of 2D square-like Bi2S3-BiOCl heterostructures with enhanced visible light-driven photocatalytic performance for dye pollutant degradation 被引量:1
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作者 Jing-jing Xu Jing-wen Yang +6 位作者 Pu Zhang Quan Yuan Yan-hong Zhu Yu Wang Miao-miao Wu Zheng-mei Wang Min-dong Chen 《Water Science and Engineering》 EI CAS CSCD 2017年第4期334-339,共6页
A series of Bi2 S3-BiOCI composites with two-dimensional(2 D) square-like structures were prepared via a two-step anion exchange route.X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron m... A series of Bi2 S3-BiOCI composites with two-dimensional(2 D) square-like structures were prepared via a two-step anion exchange route.X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), and diffuse reflectance spectra(DRS)were used to investigate the properties of the as-prepared Bi_2 S_3-BiOCI heterostructures. The coupling of BiOCl and Bi_2 S_3 induced enhanced photoabsorption efficiency and bandgap narrowing. A reactive brilliant red X-3 B dye was used as a contaminant to test the photocatalytic activity of the obtained Bi_2 S_3-BiOCl samples under visible light irradiation. The sample Bi_2 S_3-BiOCl with a mass ratio of 8:4 exhibited the highest photodegradation efficiency, which was six times higher than that of pure BiOCl. In addition, a mechanism for the enhancement of photocatalytic activity is proposed. 展开更多
关键词 PHOTOCATALYsIs BI2s3 BiOCl VIsIBLE light HETEROsTRUCTURE
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The influence of nonparaxiality on the spectral behavior in Young's experiment illuminated by partially coherent light 被引量:1
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作者 赵光普 吕百达 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3466-3472,共7页
Starting from the Rayleigh-Sommerfeld diffraction integral, this paper studies the spectral behavior in Young's experiment illuminated by nonparaxial partially coherent light and compares with the paraxial case, wher... Starting from the Rayleigh-Sommerfeld diffraction integral, this paper studies the spectral behavior in Young's experiment illuminated by nonparaxial partially coherent light and compares with the paraxial case, where the influence of nonparaxiality of partially coherent light on the spectral shifts and spectral switches is stressed. It is shown that there is a spectral shift in the nonparaxial case relative to the paraxial one and the critical position changes, at which the spectral switch occurs. The ratio of the waist width to the central wavelength ω0/λ0 and relative spatial correlation length △ affect the spectral difference. The smaller ω0/λ0 is, the larger the difference between the nonparaxial and paraxial results appears. The effect of relative spatial correlation length △ is relatively small. 展开更多
关键词 nonparaxial beams Young's experiment spectral shift and spectral switch partially coherent light
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S vacancy modulated Zn_(x)Cd_(1-x)S/CoP quantum dots for efficient H_(2) evolution from water splitting under visible light 被引量:1
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作者 Qi Xie Min Wang +5 位作者 Yong Xu Xiaoke Li Xin Zhou Liang Hong Luhua Jiang Wen-Feng Lin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第10期210-218,I0007,共10页
Energy band structure and interfacial compatibility of heterojunctions are crucial for photocatalysts in promoting photogene rated charge separation and transfer.Here,a combined strategy of vacancy engineering and qua... Energy band structure and interfacial compatibility of heterojunctions are crucial for photocatalysts in promoting photogene rated charge separation and transfer.Here,a combined strategy of vacancy engineering and quantum effect via a facile phosphating process is reported,for the first time,to modulate the energy band structure and the interface of Zn_(x)Cd_(1-x)S/CoP quantum dots(ZCS_(v)/CoP QDs)heterojunction.The combined experimental and theoretical investigation revealed that phosphating process transformed CoO_(x) QDs to CoP QDs,and more importantly,generated considerable amount of sulfur vacancies in ZCS_(v).As a result,a TypeⅡZCS_(v)/CoP QDs heterojunction with compatible interfaces was constructed via in-situ generated P-Zn,P-Cd and S-Co bonds,which facilitated the separation and transfer of the photogenerated charge and thus resulted in a high ability towards hydrogen evolution under visible light(17.53 mmol g^(-1) h^(-1)).This work provides an effective and adaptable strategy to modulate band structure and interfacial compatibility of heterojunctions via vacancy engineering and quantum effect. 展开更多
关键词 Visible light excited photocatalyst Heterojunction Zn_(x)Cd_(1-x)s/CoP quantum dot s vacancy engineering Photocatalytic hydrogen evolution
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Why and how does light therapy offer neuroprotection in Parkinson's disease? 被引量:2
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作者 John Mitrofanis 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第4期574-575,共2页
Red and infrared light (X = 600-1,070 nm) therapy, known also as photobiomodulation, has been reported to offer neu-roprotection and to improve locomotor behaviour in animal models of Parkinson's disease, from rode... Red and infrared light (X = 600-1,070 nm) therapy, known also as photobiomodulation, has been reported to offer neu-roprotection and to improve locomotor behaviour in animal models of Parkinson's disease, from rodents to non-human primates (Rojas and Gonzalez-Lima, 2011; Hamblin, 2016; Johnstone et al., 2016). The neuroprotective aspect of this therapy is particularly relevant; the saving of neurons that would normally die as a result of the parkinsonian degeneration, is without doubt, 展开更多
关键词 Why and how does light therapy offer neuroprotection in Parkinson’s disease
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Rapid Microwave-assisted Hydrothermal Synthesis of Bi0.76Sb1.24S3 and Its Application in the Photocatalytic Degradation of Pollutants by Visible Light Irradiation 被引量:2
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作者 薛珲 丁男 +3 位作者 赖深伟 陈庆华 刘欣萍 钱庆荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期59-65,共7页
Bi(0.76)Sb(1.24)S3 nanocrystals were synthesized by a rapid microwave-assisted hydrothermal method using bismuth nitrate, antimony pentoxide and thioacetamide as starting materials and characterized by X-ray diffr... Bi(0.76)Sb(1.24)S3 nanocrystals were synthesized by a rapid microwave-assisted hydrothermal method using bismuth nitrate, antimony pentoxide and thioacetamide as starting materials and characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and UV-vis diffuse reflectance spectroscopy(DRS). The effects of the synthetic condition on the product composition were investigated. The photocatalytic activities of Bi(0.76)Sb(1.24)S3 nanocrystals for the degradation of methyl orange and p-hydroxyazobenzene under visible light irradiation were evaluated. Bi(0.76)Sb(1.24)S3 exhibited good and stable visible light photocatalytic activity. 展开更多
关键词 Bi0.76sb1.24s3 microwave-assisted hydrothermal photocatalytic visible light
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Spatio-temporal Dynamics of Urbanization in China Using DMSP/OLS Nighttime Light Data from 1992–2013 被引量:1
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作者 XU Pengfei LIN Muying JIN Pingbin 《Chinese Geographical Science》 SCIE CSCD 2021年第1期70-80,共11页
Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-maki... Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development. 展开更多
关键词 Defense Meteorological satellite Program’s Operational Linescan system(DMsP/OLs)nighttime light URBANIZATION pixel level detection spatio-temporal dynamics future trends
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Effect of Photostablizers on Surface Color and Mechanical Property of Wood-flour/HDPE Composites after Weathering
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作者 薛平 贾明印 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第4期621-627,共7页
The effects of photostabilizers of ultraviolet absorbers (UVA), hindered amine light stabilizer (HALS) and pigment on surface color change and mechanical properties of weathered wood-flour/ polyethylene (HDPE) c... The effects of photostabilizers of ultraviolet absorbers (UVA), hindered amine light stabilizer (HALS) and pigment on surface color change and mechanical properties of weathered wood-flour/ polyethylene (HDPE) composites were investigated. After being added UVA with high UV absorbance, the WPC exhibites better ability to resist color fading and mechanical property loss. High molecular weight HALS is found to be the most effective in controlling long term fading and yellowing changes. Pigments cover the composites for remaining the original color after weathering regardless of less contribution to mechanical property. Addition of photostabilizer and pigment together show great synergism in decreasing color fading and flexural property loss. 展开更多
关键词 wood fiber polyethylene WEATHERING ultraviolet absorbers (UVA) hindered amine light stabilizer (HALs PIGMENT
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Evidences for Varying Speed of Light with Time 被引量:1
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作者 Giuseppe Pipino 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第2期395-411,共17页
Aims: The paper explores the hypothesis that the speed of light c is decreasing over time at rate (dc/dt)=-H? c, H being the Hubble constant. This hypothesis differs from the so-called tired light, in which the veloci... Aims: The paper explores the hypothesis that the speed of light c is decreasing over time at rate (dc/dt)=-H? c, H being the Hubble constant. This hypothesis differs from the so-called tired light, in which the velocity c is supposed to vary during the journey of photons in the empty space for some frictional mechanism. In the hypothesis of the author the speed c, during this journey, is assumed constant. In this way the problems of the tired hypothesis are overcome. Methods: The paper links the variation dc/dt with the Hubble constant and infers a value of dc/dt from the difference between the value of the variation of the Earth-Moon distance measured by the Lunar Laser Ranging Experiment and the tidal effect. Results: Under the hypothesis c time varying, we explain: 1) The cosmological redshift. 2) The anomalous acceleration ap ≈ -8 × 10-10 m?sec-2, measured for some spacecrafts. 3) The high redshift of supernovae Ia, which seems to evidence an acceleration of the expansion of the universe. 4) The peripheral motion of stars in galaxies around their rotational centre. 5) The dilation of the light curves observed for supernovae Ia. 展开更多
关键词 Lunar Laser RANGING Experiment DILATION of light Curves of sUPERNOVAE Ia REDsHIFT Hubble’s Law Dark Matter Abnormal ACCELERATION ACCELERATION of Expansion of UNIVERsE
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Succession in <i>Quercus gambelii</i>(Gambel’s Oak) Woodlands
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作者 O. W. Van Auken J. K. Bush 《American Journal of Plant Sciences》 2017年第2期96-112,共17页
Quercus gambelii (Gambel’s oak) communities are found in the mountains of the western United States from Wyoming, Colorado, and Utah south into northern Mexico. Leaf gas exchange rates were measured for potential suc... Quercus gambelii (Gambel’s oak) communities are found in the mountains of the western United States from Wyoming, Colorado, and Utah south into northern Mexico. Leaf gas exchange rates were measured for potential successional species in Q. gambelii communities. Daily average light level below the canopy was 125 μmol/m2/sec. Light response curves indicated that Pinus ponderosa and Q. gambelii had high maximum photosynthetic rates (14.13 and 11.21 μmol/m2/sec) and were sun species. Abies concolor (white fir) is a shade species with the lowest photosynthetic rate (3.71 μmol/m2/sec). At low light levels few differences in photosynthetic rates were found between the species. Pinus ponderosa and Q. gambelii maximum photosynthetic rates were reduced 71% - 73% in shade and the shade species maximum photosynthetic rates were reduced by 50% - 57%. Comparing annual gas exchange rates for all species showed that A. concolor had higher gas exchange rates and could replace Q. gambelii. Growth in height of Q. gambelii was a second order quadratic function reaching a plateau of about ten meters between 80 and 95 years. Growth estimates of height of A. concolor in canopy shade were exponential, which would allow seedlings to reach the Q. gambelii canopy in approximately 35 years. Abies concolor wood specific gravity is 56% lower than Q. gambelii, which means more carbon is put into growth in height to reach the canopy at low light levels and low photosynthetic rates. The additional shading it causes would further reduce Q. gambelii photosynthesis rates and prevent self-replacement in these Q. gambelii communities, leading to an A. concolor dominated community. 展开更多
关键词 Gas Exchange Growth Rates light Levels OAK Replacement Photosynthetic Rates Population Dynamics White Fir wood specific Gravity
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