Carbon-based materials,such as graphene and carbon nanotubes,have emerged as a transformative class of building blocks for state-of-the-art metamaterial devices due to their excellent flexibility,light weight,and tuna...Carbon-based materials,such as graphene and carbon nanotubes,have emerged as a transformative class of building blocks for state-of-the-art metamaterial devices due to their excellent flexibility,light weight,and tunability.In this work,a tunable carbon-based metal-free terahertz(THz)metasurface with ultrabroadband absorption is proposed,composed of alternating graphite and graphene patterns,where the Fermi level of graphene is adjusted by varying the applied voltage bias to achieve the tunable ultrabroadband absorption characteristics.In particular,when the Fermi level of graphene is 1 eV,the absorption coefficient exceeds 90%from 7.24 through 16.23 THz,and importantly,the absorption bandwidth reaches as much as 8.99 THz.In addition,it is polarization-insensitive to incident waves and maintains a high absorption rate at an incident angle of up to 50 deg.This carbon-based device enjoys higher absorption bandwidth,rates,and performance compared to conventional absorbers in the THz regime and can be potentially applied in various fields,including THz wave sensing,modulation,as well as wearable health care devices,and biomedicine detection.展开更多
[Objectives] To establish the quality standard of barberry branches. [Methods] Microscopic identification and thin layer identification were used to qualitatively identify barberry branches. Berberine content was dete...[Objectives] To establish the quality standard of barberry branches. [Methods] Microscopic identification and thin layer identification were used to qualitatively identify barberry branches. Berberine content was determined by HPLC method, and the content of water, total ash, acid insoluble ash and extract was detected according to the method of the Chinese Pharmacopoeia (2020 edition). [Results] The microscopic identification showed that the features were obvious, and stone cells, cork cells, epidermal cells, stomata, fibers and catheter with reticulated pores could be found. Berberine was detected in barberry branches by thin layer chromatography, and the characteristic spots were separated clearly. Moisture, total ash, and acid insoluble ash content shall not exceed 13%, 6%, and 3%, respectively, and extract content shall not be less than 10%. Berberine hydrochloride (C_(20)H_(18)ClNO_(4)) should be calculated in the branches of Berberis wilsonae Hemsley and Berberis aggregata C. K. Schneid., and berberine (C_(20)H_(17)NO_(4)) content should not be less than 0.05%. The linear relationship was good in the range of 0.002-0.240 mg/mL ( R^(2)=0.999 5). The average recovery was 89.63%, and RSD was 5.28%. [Conclusions] The method was simple, accurate and reproducible, and can be used for the quality control of barberry branches.展开更多
[Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through n...[Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through network pharmacological analysis,molecular docking simulation experiments and in vitro experiments,the main components and corresponding targets of Viola were screened out,and their anti-tumor signaling pathways were confirmed.MTT colorimetric assay was used to investigate the inhibitory effect of different extraction layers of Viola on the growth of tumor cells.[Results]18 anti-tumor active components such as 2α,19α-Dihydroxyursolic acid,Corlumine,Madolin U,Trifolirhizin and etc.,and 52 action targets such as PTGS2,PTGS1,P2RX7,MMP1,and GABRB3,and anti-tumor signaling pathways were confirmed.The results of molecular docking showed that all the selected Viola compounds had good binding activity.The results of MTT colorimetric assay showed that the petroleum ether layer and n-butanol layer had a good inhibitory effect on the growth of tumor cell lines.[Conclusions]Viola medicinal materials have the potential of anti-tumor,triterpenoids and flavonoids may be the main active components,and the petroleum ether layer and n-butanol layer have better inhibitory effect on the growth of tumor cells.展开更多
Owing to superior comprehensive performance than conventional superalloys at high temperature,refractory high entropy alloy(RHEA)is becoming a promising candidate for the next generation high-temperature material.Here...Owing to superior comprehensive performance than conventional superalloys at high temperature,refractory high entropy alloy(RHEA)is becoming a promising candidate for the next generation high-temperature material.Herein,contemporary aspects of corresponding development of RHEAs are reviewed to discuss various factors affecting the organization structure and service performance.It mainly covers alloying system and strengthening mechanism,the preparation method,plastic deformation and the related mechanism,as well as microstructure control by heat treatment.Firstly,the alloy systems and strengthening mechanism are introduced.This is followed by different preparation methods and the comparison of strengths and shortcomings based on different RHEAs.Then,hot deformation behavior and plastic deformation under different loadings are analyzed.Based on this,the influence of heat treatment on microstructures prior to and after the deformation is further summarized.Finally,some important research areas to be carried out in future are pointed out.This review will give a deep understanding of the effects of different factors on the service performance and provide scientific guide in designing RHEAs with improved performance.展开更多
High repetition rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS) was first used to analyze trace elements in copper alloy samples. The 1064 nm output of an acoustooptically Q-switched Nd:YAG laser...High repetition rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS) was first used to analyze trace elements in copper alloy samples. The 1064 nm output of an acoustooptically Q-switched Nd:YAG laser operated at a pulse repetition rate of 1 kHz was utilized to ablate copper alloy and to form original plasma, spark-discharge was applied to further breakdown the ablated samples and enhance the emission of the laser-induced plasma. A compact multichannel fiber spectrometer was used to analyze the plasma emission under nongated operation mode. Under the assistance of high repetition rate spark discharge, the plasma emission was able to be improved significantly. The determined limits of the detection of lead and aluminum were 15.5 ppm and 1.9 ppm by HRR LA-SIBS, respectively, which were 11 and 6 folds better than that determined by HRR LIBS under the same laser-ablation condition. This work demonstrates the feasibility of using fiber spectrometer to analyze plasma emission under non-gated operation mode and the possibility of building a portable HRR LA-SIBS system for rapid elemental analysis of copper alloys and other solid samples.展开更多
With the application of strain engineering in microelectronics,complex stress states are introduced into advanced semiconductor devices.However,there is still a lack of effective metrology for the decoupling analysis ...With the application of strain engineering in microelectronics,complex stress states are introduced into advanced semiconductor devices.However,there is still a lack of effective metrology for the decoupling analysis of the complex stress states in semiconductor materials.This paper presents an investigation on the 2-axis stress component decoupling of{100}monocrystalline silicon(c-Si)by using oblique backscattering micro-Raman spectroscopy.A spectral-mechanical model was established,and two practicable methods for actual stress decoupling analyses were proposed.The verification experiments demonstrated the correctness and applicability of the methods proposed in this paper.展开更多
The tunable propagation properties of 3D Dirac semimetal(DSM)-supported dielectric-loaded surface plasmons structures have been investigated in the THz regime,including the influences of the Fermi level of 3D DSM laye...The tunable propagation properties of 3D Dirac semimetal(DSM)-supported dielectric-loaded surface plasmons structures have been investigated in the THz regime,including the influences of the Fermi level of 3D DSM layer,the fiber shape and operation frequencies.The results indicate that the shape of dielectric fiber affects the hybrid mode significantly,on the condition that if ax(the semi-minor axis length of the dielectric semi-ellipse)is relatively small,the fiber shows good mode confinement and low loss simultaneously,and the figure of merit reaches more than 200.The propagation property can be manipulated in a wide range by changing the Fermi level of 3D DSM,e.g.if the Fermi level varies in the range of 0.05 eV–0.15 eV,the propagation length changes in the range of 9.073×10^(3)–2.715×10^(4)μm,and the corresponding modulation depth is 66.5%.These results are very helpful to understand the tunable mechanisms of the 3D DSM plasmonic devices,such as switchers,modulators,and sensors.展开更多
What is already known about this topic?Previous studies indicate that an increase in physical activity can diminish the risk of mortality.However,the relationship between longitudinal changes in physical activity and ...What is already known about this topic?Previous studies indicate that an increase in physical activity can diminish the risk of mortality.However,the relationship between longitudinal changes in physical activity and health improvement among Chinese adults with or without hypertension has not been explored.What is added by this report?This study found that increasing or maintaining moderate to high physical activity levels reduced the risk of all-cause mortality,irrespective of the baseline physical activity level.In addition,the beneficial effects were particularly pronounced in people with hypertension.What are the implications for public health practice?It may be beneficial to encourage adults in China,especially those with hypertension,to actively increase physical activity and deter the issue of physical inactivity that accompanies aging.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.62205204 and 62375172)the Natural Science Foundation of Shanghai (Grant No.21ZR1446500)+1 种基金the Shanghai Local College Capacity Building Project (Grant No.21010503200)Shanghai Normal University (Grant No.SK202240).
文摘Carbon-based materials,such as graphene and carbon nanotubes,have emerged as a transformative class of building blocks for state-of-the-art metamaterial devices due to their excellent flexibility,light weight,and tunability.In this work,a tunable carbon-based metal-free terahertz(THz)metasurface with ultrabroadband absorption is proposed,composed of alternating graphite and graphene patterns,where the Fermi level of graphene is adjusted by varying the applied voltage bias to achieve the tunable ultrabroadband absorption characteristics.In particular,when the Fermi level of graphene is 1 eV,the absorption coefficient exceeds 90%from 7.24 through 16.23 THz,and importantly,the absorption bandwidth reaches as much as 8.99 THz.In addition,it is polarization-insensitive to incident waves and maintains a high absorption rate at an incident angle of up to 50 deg.This carbon-based device enjoys higher absorption bandwidth,rates,and performance compared to conventional absorbers in the THz regime and can be potentially applied in various fields,including THz wave sensing,modulation,as well as wearable health care devices,and biomedicine detection.
基金Supported by the National Key Research and Development Plan(2018YFC-06101)Sichuan Provincial Natural Science Foundation(2022NSFSC1605)+2 种基金Traditional Chinese Medicine(Ethnic Medicine)Standard Improvement of Sichuan Medical Products Administration(510201202102305)Leading Talents Support Plan of National Ethnic Affairs Commission in 2022Special Project for the University-Level Innovation Team in the Fundamental Research Funds for the Central Universities(ZYN2022067).
文摘[Objectives] To establish the quality standard of barberry branches. [Methods] Microscopic identification and thin layer identification were used to qualitatively identify barberry branches. Berberine content was determined by HPLC method, and the content of water, total ash, acid insoluble ash and extract was detected according to the method of the Chinese Pharmacopoeia (2020 edition). [Results] The microscopic identification showed that the features were obvious, and stone cells, cork cells, epidermal cells, stomata, fibers and catheter with reticulated pores could be found. Berberine was detected in barberry branches by thin layer chromatography, and the characteristic spots were separated clearly. Moisture, total ash, and acid insoluble ash content shall not exceed 13%, 6%, and 3%, respectively, and extract content shall not be less than 10%. Berberine hydrochloride (C_(20)H_(18)ClNO_(4)) should be calculated in the branches of Berberis wilsonae Hemsley and Berberis aggregata C. K. Schneid., and berberine (C_(20)H_(17)NO_(4)) content should not be less than 0.05%. The linear relationship was good in the range of 0.002-0.240 mg/mL ( R^(2)=0.999 5). The average recovery was 89.63%, and RSD was 5.28%. [Conclusions] The method was simple, accurate and reproducible, and can be used for the quality control of barberry branches.
基金Supported by the National Key Research and Development Plan (2018YFC1708005)Sichuan Provincial Natural Science Foundation (Young Scientist Fund Project-2022NSFSC1588)Leading Talent Support Plan of National Ethnic Affairs Commission in 2021,Double First-Class Initiative Project of Southwest Minzu University (CX2023054).
文摘[Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through network pharmacological analysis,molecular docking simulation experiments and in vitro experiments,the main components and corresponding targets of Viola were screened out,and their anti-tumor signaling pathways were confirmed.MTT colorimetric assay was used to investigate the inhibitory effect of different extraction layers of Viola on the growth of tumor cells.[Results]18 anti-tumor active components such as 2α,19α-Dihydroxyursolic acid,Corlumine,Madolin U,Trifolirhizin and etc.,and 52 action targets such as PTGS2,PTGS1,P2RX7,MMP1,and GABRB3,and anti-tumor signaling pathways were confirmed.The results of molecular docking showed that all the selected Viola compounds had good binding activity.The results of MTT colorimetric assay showed that the petroleum ether layer and n-butanol layer had a good inhibitory effect on the growth of tumor cell lines.[Conclusions]Viola medicinal materials have the potential of anti-tumor,triterpenoids and flavonoids may be the main active components,and the petroleum ether layer and n-butanol layer have better inhibitory effect on the growth of tumor cells.
基金National Natural Science Foundation of China(Grant Nos.U2141205,51775525,52175369,52005465,52025041 and 52174294)Fast Support Program(Grant No.80923020405)Beijing Nova Program from Beijing Municipal Science&Technology Commission(Grant No.Z201100006820094).
文摘Owing to superior comprehensive performance than conventional superalloys at high temperature,refractory high entropy alloy(RHEA)is becoming a promising candidate for the next generation high-temperature material.Herein,contemporary aspects of corresponding development of RHEAs are reviewed to discuss various factors affecting the organization structure and service performance.It mainly covers alloying system and strengthening mechanism,the preparation method,plastic deformation and the related mechanism,as well as microstructure control by heat treatment.Firstly,the alloy systems and strengthening mechanism are introduced.This is followed by different preparation methods and the comparison of strengths and shortcomings based on different RHEAs.Then,hot deformation behavior and plastic deformation under different loadings are analyzed.Based on this,the influence of heat treatment on microstructures prior to and after the deformation is further summarized.Finally,some important research areas to be carried out in future are pointed out.This review will give a deep understanding of the effects of different factors on the service performance and provide scientific guide in designing RHEAs with improved performance.
基金financially supported by National Basic Research Program (973 Program) of China under grant number 2012CB921900National Natural Science Foundation of China under grant numbers 11274123 and 11304100
文摘High repetition rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS) was first used to analyze trace elements in copper alloy samples. The 1064 nm output of an acoustooptically Q-switched Nd:YAG laser operated at a pulse repetition rate of 1 kHz was utilized to ablate copper alloy and to form original plasma, spark-discharge was applied to further breakdown the ablated samples and enhance the emission of the laser-induced plasma. A compact multichannel fiber spectrometer was used to analyze the plasma emission under nongated operation mode. Under the assistance of high repetition rate spark discharge, the plasma emission was able to be improved significantly. The determined limits of the detection of lead and aluminum were 15.5 ppm and 1.9 ppm by HRR LA-SIBS, respectively, which were 11 and 6 folds better than that determined by HRR LIBS under the same laser-ablation condition. This work demonstrates the feasibility of using fiber spectrometer to analyze plasma emission under non-gated operation mode and the possibility of building a portable HRR LA-SIBS system for rapid elemental analysis of copper alloys and other solid samples.
基金the National Key Research and Development Program of China(Grant No.2018YFB0703500)the National Natural Science Foundation of China(Grant Nos.11827802,11772223,11772227,11890680,and 61727810)。
文摘With the application of strain engineering in microelectronics,complex stress states are introduced into advanced semiconductor devices.However,there is still a lack of effective metrology for the decoupling analysis of the complex stress states in semiconductor materials.This paper presents an investigation on the 2-axis stress component decoupling of{100}monocrystalline silicon(c-Si)by using oblique backscattering micro-Raman spectroscopy.A spectral-mechanical model was established,and two practicable methods for actual stress decoupling analyses were proposed.The verification experiments demonstrated the correctness and applicability of the methods proposed in this paper.
基金the Natural Science Foundation of Shanghai under Grant Nos.21ZR1446500Shanghai Local College Capacity Building Project under Grant No.22010503300 and 21010503200+4 种基金the Research Funding of Shanghai Normal University under Grant No.SK202240National Natural Science Foundation of China under Grant Nos.61674106,12073018,U1931205the Funding of Shanghai Municipal Education Commission under Grant No 2019-01-07-00-02-E00032the Funding of Shanghai Municipality Science and Technology Commission under Grant No 19590746000,20070502400,YDZX20203100002498Student Research Project of Shanghai Normal University(undergraduate)under Grant No.22LKY022.
文摘The tunable propagation properties of 3D Dirac semimetal(DSM)-supported dielectric-loaded surface plasmons structures have been investigated in the THz regime,including the influences of the Fermi level of 3D DSM layer,the fiber shape and operation frequencies.The results indicate that the shape of dielectric fiber affects the hybrid mode significantly,on the condition that if ax(the semi-minor axis length of the dielectric semi-ellipse)is relatively small,the fiber shows good mode confinement and low loss simultaneously,and the figure of merit reaches more than 200.The propagation property can be manipulated in a wide range by changing the Fermi level of 3D DSM,e.g.if the Fermi level varies in the range of 0.05 eV–0.15 eV,the propagation length changes in the range of 9.073×10^(3)–2.715×10^(4)μm,and the corresponding modulation depth is 66.5%.These results are very helpful to understand the tunable mechanisms of the 3D DSM plasmonic devices,such as switchers,modulators,and sensors.
基金supported by the National Key Research and Development Program of China(2018YFC1313900,2018YFC1313904).
文摘What is already known about this topic?Previous studies indicate that an increase in physical activity can diminish the risk of mortality.However,the relationship between longitudinal changes in physical activity and health improvement among Chinese adults with or without hypertension has not been explored.What is added by this report?This study found that increasing or maintaining moderate to high physical activity levels reduced the risk of all-cause mortality,irrespective of the baseline physical activity level.In addition,the beneficial effects were particularly pronounced in people with hypertension.What are the implications for public health practice?It may be beneficial to encourage adults in China,especially those with hypertension,to actively increase physical activity and deter the issue of physical inactivity that accompanies aging.
