We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magne...We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion.展开更多
We present the synthesis of TaCoTe_(2) single crystals and a systematic investigation of the physical properties of bulk crystals and thin flakes.The crystal shows a semiconducting behavior with temperature decreasing...We present the synthesis of TaCoTe_(2) single crystals and a systematic investigation of the physical properties of bulk crystals and thin flakes.The crystal shows a semiconducting behavior with temperature decreasing from room temperature and turns to a metallic behavior below 38 K.When the magnetic field is applied,the temperature-dependent resistivity curves show an upturn below 10 K.Furthermore,we find that the TaCoTe_(2) single crystal can be easily exfoliated from the bulk crystal by the micromechanical exfoliation method.Our measurements suggest that the nanoflakes have properties similar to those of the bulk crystal when the thickness is lowered to 18 nm.展开更多
The compounds composed of transition metal cations and pnictide anions provide a rich platform for studying novel physical phenomena.Here we report on the observation of a phase transition at~70 K and 145 K in layered...The compounds composed of transition metal cations and pnictide anions provide a rich platform for studying novel physical phenomena.Here we report on the observation of a phase transition at~70 K and 145 K in layered compound EuCu_(4)As_(2)and SrCu_(4)As_(2),respectively.from both the transport and heat capacity.The thermal expansion measurements show that the variation of the lattice parameters(△L_(b)/L_(ab))around T_(P) is much less than that for a typical crystalline phase transition.Our experimental results reveal that the transition in EuCu_(4)As_(2)and SrCu_(4)As_(2)should be driven by subtle structural-distortion.展开更多
[Objectives]To determine the optimal reflux extraction process conditions for Compound Coptis Ointment.[Methods]The study employed the orthogonal experimental design method and drug-sensitive disc agar diffusion metho...[Objectives]To determine the optimal reflux extraction process conditions for Compound Coptis Ointment.[Methods]The study employed the orthogonal experimental design method and drug-sensitive disc agar diffusion method to evaluate the extraction rate,berberine hydrochloride content,and bacteriostatic ring diameter of the extract as comprehensive indices,and optimized the extraction process conditions of Compound Coptis Ointment using ethanol reflux.[Results]Based on the results of comprehensive indices,the optimal reflux extraction conditions for Compound Coptis Ointment were determined to be soaking in 1.5 times the amount of 70%ethanol for 2 h,followed by two extractions with 6 times the amount of 70%ethanol for 1 h each time.Three verification tests were conducted under the optimal process conditions.The yield of the extract was 28.32%±0.53%,the content of berberine hydrochloride was 4.68%±0.45%,and the diameter of the bacteriostatic ring was(2.5±0.2)cm.[Conclusions]The extract had higher drug content and exhibited better antibacterial effects.The optimized extraction process is simple,stable,and reliable,and can be effectively used to optimize the extraction process of Compound Coptis Ointment.展开更多
Optical gain enhancement of two-dimensional CsPbBr3 nanosheets was studied when the amplified spontaneous emission is guided by a patterned structure of polyurethane-acrylate.Given the uncertainties and pitfalls in re...Optical gain enhancement of two-dimensional CsPbBr3 nanosheets was studied when the amplified spontaneous emission is guided by a patterned structure of polyurethane-acrylate.Given the uncertainties and pitfalls in retrieving a gain coefficient from the variable stripe length method,a gain contour g((h))ω.x)was obtained in the plane of spectrum energy(hω)and stripe length(x),whereby an average gain was obtained,and gain saturation was analysed.Excitation and temperature dependence of the gain contour show that the waveguide enhances both gain and thermal stability due to the increased optical confinement and heat dissipation,and the gain origins were attributed to the two-dimensional excitons and the localized states.展开更多
基金Project supported by the National Key Research and Development Program of China (Grant Nos.2023YFA1607403,2021YFA1600201,and 2022YFA1602603)the Natural Science Foundation of China (Grant Nos.U19A2093,U2032214,and U2032163)+5 种基金the Collaborative Innovation Program of Hefei Science Center,CAS (Grant No.2019HSC-CIP 001)the Youth Innovation Promotion Association of CAS (Grant No.2021117)the Natural Science Foundation of Anhui Province (No.1908085QA15)the HFIPS Director’s Fund (Grant No.YZJJQY202304)the CASHIPS Director’s Fund (Grant No.YZJJ2022QN36)supported by the High Magnetic Field Laboratory of Anhui Province。
文摘We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion.
基金Project supported by the National Key Research and Development Program of China (Grant No.2021YFA1600201)the National Natural Science Foundation of China (Grant Nos.U19A2093,U2032214,and U2032163)+4 种基金Collaborative Innovation Program of Hefei Science Center,CAS (Grant No.2019HSC-CIP 001)Youth Innovation Promotion Association of CAS (Grant No.2021117)the HFIPS Director’s Fund (Grant No.YZJJQY202304)the CASHIPS Director’s Fund (Grant No.E26MMG71131)supported by the High Magnetic Field Laboratory of Anhui Province。
文摘We present the synthesis of TaCoTe_(2) single crystals and a systematic investigation of the physical properties of bulk crystals and thin flakes.The crystal shows a semiconducting behavior with temperature decreasing from room temperature and turns to a metallic behavior below 38 K.When the magnetic field is applied,the temperature-dependent resistivity curves show an upturn below 10 K.Furthermore,we find that the TaCoTe_(2) single crystal can be easily exfoliated from the bulk crystal by the micromechanical exfoliation method.Our measurements suggest that the nanoflakes have properties similar to those of the bulk crystal when the thickness is lowered to 18 nm.
基金Project supported by the National Key Research and Development Program of China(Grant No.2021YFA1600201)the National Natural Science Foundation of China(Grant Nos.U19A2093,U2032214,U2032163,U1732274,11904002,and 11874359)+5 种基金the Collaborative Innovation Program of Hefei Science Center,Chinese Academy of Sciences(CAS)(Grant No.2019HSC-CIP 001)the Youth Innovation Promotion Association of CAS(Grant No.2021117)the Natural Science Foundation of Anhui Province,China(Grant No.1908085QA15)the Director Fund from the Hefei Institutes of Physical Science(HFIPS)(Grant No.YZJJQY202304)the Director Fund from the the Chinese Academy of Sciences and Hefei Institutes of Physical Science(CASHIPS),China(Grant No.E26MMG71131)the High Magnetic Field Laboratory of Anhui Province,China。
文摘The compounds composed of transition metal cations and pnictide anions provide a rich platform for studying novel physical phenomena.Here we report on the observation of a phase transition at~70 K and 145 K in layered compound EuCu_(4)As_(2)and SrCu_(4)As_(2),respectively.from both the transport and heat capacity.The thermal expansion measurements show that the variation of the lattice parameters(△L_(b)/L_(ab))around T_(P) is much less than that for a typical crystalline phase transition.Our experimental results reveal that the transition in EuCu_(4)As_(2)and SrCu_(4)As_(2)should be driven by subtle structural-distortion.
基金Supported by Key Research Project of Wuhan Municipal Health Commission(WZ21A08).
文摘[Objectives]To determine the optimal reflux extraction process conditions for Compound Coptis Ointment.[Methods]The study employed the orthogonal experimental design method and drug-sensitive disc agar diffusion method to evaluate the extraction rate,berberine hydrochloride content,and bacteriostatic ring diameter of the extract as comprehensive indices,and optimized the extraction process conditions of Compound Coptis Ointment using ethanol reflux.[Results]Based on the results of comprehensive indices,the optimal reflux extraction conditions for Compound Coptis Ointment were determined to be soaking in 1.5 times the amount of 70%ethanol for 2 h,followed by two extractions with 6 times the amount of 70%ethanol for 1 h each time.Three verification tests were conducted under the optimal process conditions.The yield of the extract was 28.32%±0.53%,the content of berberine hydrochloride was 4.68%±0.45%,and the diameter of the bacteriostatic ring was(2.5±0.2)cm.[Conclusions]The extract had higher drug content and exhibited better antibacterial effects.The optimized extraction process is simple,stable,and reliable,and can be effectively used to optimize the extraction process of Compound Coptis Ointment.
基金supported by the NRF funded by the Ministry of Science,MSIT,and ICT(BrainLink RS-2023-00236798,RLRC 2022R1A5A8023404,NRF-2022R1I1A1A01064278,NRF-2021R1A5A1032937,RF-2021M3H4A6A02045432).
文摘Optical gain enhancement of two-dimensional CsPbBr3 nanosheets was studied when the amplified spontaneous emission is guided by a patterned structure of polyurethane-acrylate.Given the uncertainties and pitfalls in retrieving a gain coefficient from the variable stripe length method,a gain contour g((h))ω.x)was obtained in the plane of spectrum energy(hω)and stripe length(x),whereby an average gain was obtained,and gain saturation was analysed.Excitation and temperature dependence of the gain contour show that the waveguide enhances both gain and thermal stability due to the increased optical confinement and heat dissipation,and the gain origins were attributed to the two-dimensional excitons and the localized states.
