[Objectives]This study aimed to establish a method for simultaneous determination of four ingredients in Guanxin Danshen tablets by RP-HPLC.[Methods]HPLC chromatography was adopted with column of Thermo Hypersil-Keyst...[Objectives]This study aimed to establish a method for simultaneous determination of four ingredients in Guanxin Danshen tablets by RP-HPLC.[Methods]HPLC chromatography was adopted with column of Thermo Hypersil-Keystone C 18 column(4.6 mm×250 mm,5μm),mobile phase of acetonitrile(A)-0.03 mol/L ammonium acetate(pH adjusted to 2.4 with formic acid)(B),gradient elution(0-5 min,5%A;5-10 min,5%A→19%A;10-40 min,19%A;40-68 min,19%A→36%A;68-90 min,36%A→95%A),flow rate of 1.0 mL/min and column temperature of 25℃.[Results]The content of salvianic acid A sodium,protocatechuic aldehyde,salvianolic acid B and tanshinone II A showed good linear relationship with chromatographic peak area in the range of 3.310-18.66,0.03950-0.2370,0.7500-4.500,0.05920-0.3550μg,respectively.The recovery rate(n=6)was 101.75%,96.86%,104.15%and 99.03%,respectively,and the RSD was 1.52%,2.81%,1.80%,and 1.37%respectively.The established method has good precision,reproducibility and stability.[Conclusions]This method can be used for the quality control of multiple ingredients of Guanxin Danshen tablets.展开更多
The quantum network makes use of quantum states to transmit data,which will revolutionize classical communication and allow for some breakthrough applications.Quantum key distribution(QKD)is one prominent application ...The quantum network makes use of quantum states to transmit data,which will revolutionize classical communication and allow for some breakthrough applications.Quantum key distribution(QKD)is one prominent application of quantum networks,and can protect data transmission through quantum mechanics.In this work,we propose an expandable and cost-effective quantum access network,in which the round-trip structure makes quantum states travel in a circle to carry information,and the multi-band technique is proposed to support multiuser access.Based on the round-trip multi-band quantum access network,we realize multi-user secure key sharing through the continuous-variable QKD(CV-QKD)protocol.Due to the encoding characteristics of CV-QKD,the quadrature components in different frequency bands can be used to transmit key information for different users.The feasibility of this scheme is confirmed by comprehensive noise analysis,and is verified by a proof-of-principle experiment.The results show that each user can achieve excess noise suppression and 600 bit/s level secure key generation under 30 km standard fiber transmission.Such networks have the ability of multi-user access theoretically and could be expanded by plugging in simple modules.Therefore,it paves the way for near-term largescale quantum secure networks.展开更多
Integrated quantum key distribution(QKD)systems based on photonic chips have high scalability and stability,and are promising for further construction of global quantum communications networks.On-chip quantum light so...Integrated quantum key distribution(QKD)systems based on photonic chips have high scalability and stability,and are promising for further construction of global quantum communications networks.On-chip quantum light sources are a critical component of a fully integrated QKD system;especially a continuous-variable QKD(CVQKD)system based on coherent detection,which has extremely high requirements for the light sources.Here,for what we believe is the first time,we designed and fabricated two on-chip tunable lasers for CV-QKD,and demonstrated a high-performance system based on these sources.Because of the high output power,fine tunability,and narrow linewidth,the involved on-chip lasers guarantee the accurate shot-noise-limited detection of quantum signals,center wavelength alignment of nonhomologous lasers,and suppression of untrusted excess noise.The system’s secret key rate can reach 0.75 Mb/s at a 50 km fiber distance,and the secure transmission distance can exceed 100 km.Our results mark a breakthrough toward building a fully integrated CV-QKD,and pave the way for a reliable and efficient terrestrial quantum-secure metropolitan area network.展开更多
Exploring high sensitivity on the measurement of angular rotations is an outstanding challenge in optics and metrology.In this work,we employ the mn-order Hermite-Gaussian(HG) beam in the weak measurement scheme with ...Exploring high sensitivity on the measurement of angular rotations is an outstanding challenge in optics and metrology.In this work,we employ the mn-order Hermite-Gaussian(HG) beam in the weak measurement scheme with an angular rotation interaction,where the rotation information is taken by another HG mode state completely after the post-selection.By taking a projective measurement on the final light beam,the precision of angular rotation is improved by a factor of 2mn+m+n.For verification,we perform an optical experiment where the minimum detectable angular rotation improves √15-fold with HG55 mode over that of HG11 mode,and achieves a sub-microradian scale of the measurement precision.Our theoretical framework and experimental results not only provide a more practical and convenient scheme for ultrasensitive measurement of angular rotations but also contribute to a wide range of applications in quantum metrology.展开更多
基金Supported by Science and Technology Research Project of Jiangxi Provincial Department of Education(GJJ181381)
文摘[Objectives]This study aimed to establish a method for simultaneous determination of four ingredients in Guanxin Danshen tablets by RP-HPLC.[Methods]HPLC chromatography was adopted with column of Thermo Hypersil-Keystone C 18 column(4.6 mm×250 mm,5μm),mobile phase of acetonitrile(A)-0.03 mol/L ammonium acetate(pH adjusted to 2.4 with formic acid)(B),gradient elution(0-5 min,5%A;5-10 min,5%A→19%A;10-40 min,19%A;40-68 min,19%A→36%A;68-90 min,36%A→95%A),flow rate of 1.0 mL/min and column temperature of 25℃.[Results]The content of salvianic acid A sodium,protocatechuic aldehyde,salvianolic acid B and tanshinone II A showed good linear relationship with chromatographic peak area in the range of 3.310-18.66,0.03950-0.2370,0.7500-4.500,0.05920-0.3550μg,respectively.The recovery rate(n=6)was 101.75%,96.86%,104.15%and 99.03%,respectively,and the RSD was 1.52%,2.81%,1.80%,and 1.37%respectively.The established method has good precision,reproducibility and stability.[Conclusions]This method can be used for the quality control of multiple ingredients of Guanxin Danshen tablets.
基金Key R&D Program of Guangdong Province(2020B030304002)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)+1 种基金National Natural Science Foundation of China(61671287,61971276,62101320)National Key Research and Development Program of China(2016YFA0302600)。
文摘The quantum network makes use of quantum states to transmit data,which will revolutionize classical communication and allow for some breakthrough applications.Quantum key distribution(QKD)is one prominent application of quantum networks,and can protect data transmission through quantum mechanics.In this work,we propose an expandable and cost-effective quantum access network,in which the round-trip structure makes quantum states travel in a circle to carry information,and the multi-band technique is proposed to support multiuser access.Based on the round-trip multi-band quantum access network,we realize multi-user secure key sharing through the continuous-variable QKD(CV-QKD)protocol.Due to the encoding characteristics of CV-QKD,the quadrature components in different frequency bands can be used to transmit key information for different users.The feasibility of this scheme is confirmed by comprehensive noise analysis,and is verified by a proof-of-principle experiment.The results show that each user can achieve excess noise suppression and 600 bit/s level secure key generation under 30 km standard fiber transmission.Such networks have the ability of multi-user access theoretically and could be expanded by plugging in simple modules.Therefore,it paves the way for near-term largescale quantum secure networks.
基金Special Project for Research and Development in Key areas of Guangdong Province(2020B030304002)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)+1 种基金National Natural Science Foundation of China(61671287,61971276,62101320)National Key Research and Development Program of China(2016YFA0302600)。
文摘Integrated quantum key distribution(QKD)systems based on photonic chips have high scalability and stability,and are promising for further construction of global quantum communications networks.On-chip quantum light sources are a critical component of a fully integrated QKD system;especially a continuous-variable QKD(CVQKD)system based on coherent detection,which has extremely high requirements for the light sources.Here,for what we believe is the first time,we designed and fabricated two on-chip tunable lasers for CV-QKD,and demonstrated a high-performance system based on these sources.Because of the high output power,fine tunability,and narrow linewidth,the involved on-chip lasers guarantee the accurate shot-noise-limited detection of quantum signals,center wavelength alignment of nonhomologous lasers,and suppression of untrusted excess noise.The system’s secret key rate can reach 0.75 Mb/s at a 50 km fiber distance,and the secure transmission distance can exceed 100 km.Our results mark a breakthrough toward building a fully integrated CV-QKD,and pave the way for a reliable and efficient terrestrial quantum-secure metropolitan area network.
基金National Natural Science Foundation of China(61631014,61671287,61901258,62071298)State Key Laboratory of Advanced Optical Communication Systems and Networks。
文摘Exploring high sensitivity on the measurement of angular rotations is an outstanding challenge in optics and metrology.In this work,we employ the mn-order Hermite-Gaussian(HG) beam in the weak measurement scheme with an angular rotation interaction,where the rotation information is taken by another HG mode state completely after the post-selection.By taking a projective measurement on the final light beam,the precision of angular rotation is improved by a factor of 2mn+m+n.For verification,we perform an optical experiment where the minimum detectable angular rotation improves √15-fold with HG55 mode over that of HG11 mode,and achieves a sub-microradian scale of the measurement precision.Our theoretical framework and experimental results not only provide a more practical and convenient scheme for ultrasensitive measurement of angular rotations but also contribute to a wide range of applications in quantum metrology.
