In the present study,a simple method for the preparation of a luminescent flexible gallium doped zinc oxide(GZO)/polystyrene nanocomposite film was developed.The prepared GZO powder was characterized through different...In the present study,a simple method for the preparation of a luminescent flexible gallium doped zinc oxide(GZO)/polystyrene nanocomposite film was developed.The prepared GZO powder was characterized through different optical and structural techniques.The XRD study revealed the existence of a wurtzite structure with no extra oxide peaks.Elemental-mapping,EDX,FTIR and XPS analyses were used to confirm the presence of elements and the several groups present in the structure.Under excitations of UV,the prepared hybrid nanocomposite showed a strong cyan emission with narrow full width at half the maximum value(20 nm)that has not been reported before.X-ray and laser-induced luminescence results of the hy-brid film revealed novel blue-green emission at room temperature.The prepared composite film showed a strong scintillation re-sponse to ionizing radiation.The strong emissions,very weak deep-level emissions,and low FWHM of composite indicate the de-sirable optical properties with low-density structural defects in the GZO composite structure.Therefore,the prepared hybrid film can be considered to be a suitable candidate for the fabrication of optoelectronic devices.展开更多
There are many strategies to maintain the excellent photoluminescence(PL) characteristics of perovskite quantum dots(QDs). Here, we proposed a facile and effective method to prepare cyan CsPb(Cl/Br)3/SiO2 nanospheres ...There are many strategies to maintain the excellent photoluminescence(PL) characteristics of perovskite quantum dots(QDs). Here, we proposed a facile and effective method to prepare cyan CsPb(Cl/Br)3/SiO2 nanospheres at room temperature. Cubic CsPb(Cl/Br)3 was obtained by adding a LiCl-H2O solution and anion exchange reaction. With(3-aminopropyl)triethoxysilane as an auxiliary agent, a QDs/SiO2 composite was extracted from a sol-gel solution by precipitate-encapsulation method. The transmission electron microscopy images and Fourier transform infrared spectra indicated the QDs were indeed embedded in silica substances.Besides, humidity stability and thermal stability show the composite possesses a great application value.Finally, cyan QDs@SiO2 powder has a high PL quantum yield of up to 84%;the stable cyan fluorescent powder does have great potential to play a key role in commercial full spectrum display.展开更多
The effect of freeze-thaw(F-T)cycles on the mechanical behaviors and internal mechanism of rock mass is a critical research topic.In permafrost or seasonally frozen regions,F-T cycles have adverse effects on the mecha...The effect of freeze-thaw(F-T)cycles on the mechanical behaviors and internal mechanism of rock mass is a critical research topic.In permafrost or seasonally frozen regions,F-T cycles have adverse effects on the mechanical properties of rock mass,leading to many serious disasters in mining and geotechnical operations.In this paper,uniaxial compression tests are carried out on cyan sandstone after different F-T cycles.The failure modes and damage evolution of cyan sandstone under F-T cycles are studied.In addition,from the perspective of fracture and pore volume,the calculation equations of rock strain under frost heaving pressure and F-T cycles are established and verified with the corresponding laboratory tests.Subsequently,based on the classical damage theory,the F-T damage variables of cyan sandstone under different F-T cycles are calculated,and the meso-damage calculation model of cyan sandstone under F-T-loading coupling conditions is derived.Furthermore,through the discrete element numerical simulation software(PFC^(3D)),the microscopic damage evolution process of cyan sandstone under uniaxial compression after F-T cycles is studied,including the change of microcracks number,distribution of microcracks,and the acoustic emission(AE)count.The goal of this study is to investigate the damage evolution mechanism of rock from the mesoscopic and microscopic aspects,which has certain guiding value for accurately understanding the damage characteristics of rock in cold regions.展开更多
Indigo naturalis(青黛)is also called“indigo flower,”“bright cyan,”and“cyan clam powder.”The alias“indigo flower”shows its complex progress about producing dyes.The alias“bright cyan”vividly displays the visu...Indigo naturalis(青黛)is also called“indigo flower,”“bright cyan,”and“cyan clam powder.”The alias“indigo flower”shows its complex progress about producing dyes.The alias“bright cyan”vividly displays the visual characteristics of indigo naturalis.Its another alias“cyan clam powder”implies its properties,flavors,and particular morphologic characteristics.The name of“indigo naturalis”emphasizes its wide use in ancient times to paint their eyebrows.Indigo naturalis,which comes from the Persian Kingdom,wins the favor and praise of customers in the respects of dye and cosmetics in both Eastern and Western Regions.It not only shows the infinite charm of dye culture in the Western Regions and provides a visual sensation for people,but also adds new color for Chinese medicine culture.展开更多
基金the Iranian National Elites Foundation for the financial support of this research
文摘In the present study,a simple method for the preparation of a luminescent flexible gallium doped zinc oxide(GZO)/polystyrene nanocomposite film was developed.The prepared GZO powder was characterized through different optical and structural techniques.The XRD study revealed the existence of a wurtzite structure with no extra oxide peaks.Elemental-mapping,EDX,FTIR and XPS analyses were used to confirm the presence of elements and the several groups present in the structure.Under excitations of UV,the prepared hybrid nanocomposite showed a strong cyan emission with narrow full width at half the maximum value(20 nm)that has not been reported before.X-ray and laser-induced luminescence results of the hy-brid film revealed novel blue-green emission at room temperature.The prepared composite film showed a strong scintillation re-sponse to ionizing radiation.The strong emissions,very weak deep-level emissions,and low FWHM of composite indicate the de-sirable optical properties with low-density structural defects in the GZO composite structure.Therefore,the prepared hybrid film can be considered to be a suitable candidate for the fabrication of optoelectronic devices.
基金supported by the Science and Technology Planning Project of Zhejiang Province(No.2018C01046)Enterprise-Funded Latitudinal Research Projects of China(Nos.J2016-141,J2017-171,J2017-293,and J2017-243)+1 种基金Shanghai Sailing Program(No.18YF1422500)Research Start-Up Project of Shanghai Institute of Technology(No.YJ2018-9)
文摘There are many strategies to maintain the excellent photoluminescence(PL) characteristics of perovskite quantum dots(QDs). Here, we proposed a facile and effective method to prepare cyan CsPb(Cl/Br)3/SiO2 nanospheres at room temperature. Cubic CsPb(Cl/Br)3 was obtained by adding a LiCl-H2O solution and anion exchange reaction. With(3-aminopropyl)triethoxysilane as an auxiliary agent, a QDs/SiO2 composite was extracted from a sol-gel solution by precipitate-encapsulation method. The transmission electron microscopy images and Fourier transform infrared spectra indicated the QDs were indeed embedded in silica substances.Besides, humidity stability and thermal stability show the composite possesses a great application value.Finally, cyan QDs@SiO2 powder has a high PL quantum yield of up to 84%;the stable cyan fluorescent powder does have great potential to play a key role in commercial full spectrum display.
基金Projects(52474167,52104109)supported by the National Natural Science Foundation of ChinaProject(2022JJ40602)supported by the Natural Science Foundation of Hunan Province,China。
文摘The effect of freeze-thaw(F-T)cycles on the mechanical behaviors and internal mechanism of rock mass is a critical research topic.In permafrost or seasonally frozen regions,F-T cycles have adverse effects on the mechanical properties of rock mass,leading to many serious disasters in mining and geotechnical operations.In this paper,uniaxial compression tests are carried out on cyan sandstone after different F-T cycles.The failure modes and damage evolution of cyan sandstone under F-T cycles are studied.In addition,from the perspective of fracture and pore volume,the calculation equations of rock strain under frost heaving pressure and F-T cycles are established and verified with the corresponding laboratory tests.Subsequently,based on the classical damage theory,the F-T damage variables of cyan sandstone under different F-T cycles are calculated,and the meso-damage calculation model of cyan sandstone under F-T-loading coupling conditions is derived.Furthermore,through the discrete element numerical simulation software(PFC^(3D)),the microscopic damage evolution process of cyan sandstone under uniaxial compression after F-T cycles is studied,including the change of microcracks number,distribution of microcracks,and the acoustic emission(AE)count.The goal of this study is to investigate the damage evolution mechanism of rock from the mesoscopic and microscopic aspects,which has certain guiding value for accurately understanding the damage characteristics of rock in cold regions.
文摘Indigo naturalis(青黛)is also called“indigo flower,”“bright cyan,”and“cyan clam powder.”The alias“indigo flower”shows its complex progress about producing dyes.The alias“bright cyan”vividly displays the visual characteristics of indigo naturalis.Its another alias“cyan clam powder”implies its properties,flavors,and particular morphologic characteristics.The name of“indigo naturalis”emphasizes its wide use in ancient times to paint their eyebrows.Indigo naturalis,which comes from the Persian Kingdom,wins the favor and praise of customers in the respects of dye and cosmetics in both Eastern and Western Regions.It not only shows the infinite charm of dye culture in the Western Regions and provides a visual sensation for people,but also adds new color for Chinese medicine culture.
