Air nanobubbles(A-NBs)were used to inhibit the brass corrosion in circulating cooling water for the first time in the study.The results of mass loss method and electrochemical method showed that A-NBs had the obvious ...Air nanobubbles(A-NBs)were used to inhibit the brass corrosion in circulating cooling water for the first time in the study.The results of mass loss method and electrochemical method showed that A-NBs had the obvious corrosion inhibition effect.The inhibition rate reached 52%at 35℃.The impedance and surface characterization results of corrosion samples indicated that the corrosion inhibition mechanisms of A-NBs mainly included adsorption of corrosion ions,promoting the formation of the passivation film on metal surface and the formation of the bubble layer and scale film on metal surface.A-NBs are potential excellent corrosion inhibitors.展开更多
Lithium cobalt oxide(LiCoO_(2))is proverbially employed as cathode materials of lithium-ion batteries attributed to the high theoretical capacity,and currently,it is developing towards higher cut-off voltages in the p...Lithium cobalt oxide(LiCoO_(2))is proverbially employed as cathode materials of lithium-ion batteries attributed to the high theoretical capacity,and currently,it is developing towards higher cut-off voltages in the pursuit of higher energy density.However,it suffers from serious structural degradation and surface side reactions,in particular,at the voltage above 4.60 V,leading to rapid decay of the battery life.Taking into account the desirable oxygen buffering property and the fast ion mobility characteristic of cerium oxide fluoride,in this work,we prepared Ce&F co-modified LiCoO_(2)by using the precursors of Ce(NO_(3))_(3)·6H_(2)O and NH_(4)F,and evaluated the electrochemical performance under voltages exceeding 4.60 V.The results indicated that the modified samples have multiphase heterostructure of surface CeO_(2-x)and unique Ce-O-F solid solution phase.At 3.0–4.60 V and 25℃,the preferred sample LCO-0.5Ce-0.3F has a high initial discharge specific capacity of 221.9 mA h g^(-1)at 0.1 C,with the retention of 80.3%and 89.6%after 300 cycles at 1 and 5 C,comparing with the pristine LCO(56.4%and 22.6%).And at 3.0–4.65 V,its retention is 64.0%after 300 cycles at 1 C,versus 8.5%of the pristine LCO.Through structural characterizations and DFT calculations,it suggests that Ce^(4+)&F^(-)co-doping suppresses the H3 to H1/3 irreversible phase transition,stabilizes the lattice structure,and reduces the redox activity of the lattice oxygen by modulating the Co 3d–O 2p energy band,consequently improving the electrochemical performance of LiCoO_(2)at high voltages.展开更多
Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects o...Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects of LF.Fingerprints of ten batches of LF were established by UPLC-PDA.The inhibitory levels of AST and ALT were used as pharmacological indexes,and secoxyloganin,isochlorogenic acid A and isochlorogenic acid C were screened as hepatoprotective active compounds by grey relational analysis(GRA)and partial least squares regression analysis(PLSR).Caspase-3 was obtained by network pharmacology as a key target of hepatoprotective active compounds.Molecular docking is used to explore the interaction between small molecules and proteins.This work provided a general model of the combination of UPLC-PDA and hepatoprotective effect to study the spectrum-effect relationship of LF,which can be used to considerable methods and insight for the fundamental research of the material basis of similar healthcare food.展开更多
Vanadium-titanium-based catalysts are the most widely used industrial materials for NO_x removal from coal-fired power plants. Owing to their relatively poor low-temperature deNO_x activity, low thermal stability, ins...Vanadium-titanium-based catalysts are the most widely used industrial materials for NO_x removal from coal-fired power plants. Owing to their relatively poor low-temperature deNO_x activity, low thermal stability, insufficient Hg^0 oxidation activity, SO_2 oxidation, ammonia slip, and other disadvantages,modifications to traditional vanadium-titanium-based selective catalytic reduction(SCR)catalysts have been attempted by many researchers to promote their relevant performance. This article reviewed the research progress of modified vanadium-titanium-based SCR catalysts from seven aspects, namely,(1) improving low-temperature deNO_x efficiency,(2) enhancing thermal stability,(3) improving Hg^0 oxidation efficiency,(4) oxidizing slip ammonia,(5) reducing SO_2 oxidation,(6) increasing alkali resistance, and(7) others. Their catalytic performance and the influence mechanisms have been discussed in detail. These catalysts were also divided into different categories according to their modified components such as noble metals(e.g., silver, ruthenium), transition metals(e.g., manganese, iron, copper, zirconium, etc.), rare earth metals(e.g., cerium, praseodymium),and other metal chlorides(e.g., calcium chloride, copper chloride) and non-metals(fluorine,sulfur, silicon, nitrogen, etc.). The advantages and disadvantages of these catalysts were summarized.Based on previous studies and the author's point of view, doping the appropriate modified components is beneficial to further improve the overall performance of vanadium-titanium-based SCR catalysts. This has enormous development potential and is a promising way to realize the control of multiple pollutants on the basis of the existing flue gas treatment system.展开更多
In the methods of image thresholding segmentation, such methods based on two-dimensional (2D) histogram and optimal objective functions are important. However, when they are used for infrared image segmentation, the...In the methods of image thresholding segmentation, such methods based on two-dimensional (2D) histogram and optimal objective functions are important. However, when they are used for infrared image segmentation, they are weak in suppressing background noises and worse in segmenting targets with non-uniform gray level. The concept of 2D histogram shape modification is proposed, which is realized by target information prior restraint after enhancing target information using plateau histogram equalization. The formula of 2D minimum Renyi entropy is deduced for image segmentation, then the shape-modified 2D histogram is combined wfth four optimal objective functions (i.e., maximum between-class variance, maximum entropy, maximum correlation and minimum Renyi entropy) respectively for the appli- cation of infrared image segmentation. Simultaneously, F-measure is introduced to evaluate the segmentation effects objectively. The experimental results show that F-measure is an effective evaluation index for image segmentation since its value is fully consistent with the subjective evaluation, and after 2D histogram shape modification, the methods of optimal objective functions can overcome their original forms' deficiency and their segmentation effects are more or less improvements, where the best one is the maximum entropy method based on 2D histogram shape modification.展开更多
Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully...Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward.Several approaches have been proposed and demonstrated to address this issue.In this paper,a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented.Representative device demonstrations,including ultra-narrow linewidthⅢ-Ⅴ/Si lasers,fully integratedⅢ-Ⅴ/Si/Si3N4 lasers,high-channel count mode locked quantum dot(QD)lasers,and high gain QD amplifiers will be covered.展开更多
Firstly,this paper discussed differences between traditional urbanization and new urbanization. Then,from current situations of financial support for new urbanization,it analyzed existing problems in financial support...Firstly,this paper discussed differences between traditional urbanization and new urbanization. Then,from current situations of financial support for new urbanization,it analyzed existing problems in financial support for new urbanization. The problems include difficulty in infrastructure financing,shortage of funds for small and medium sized enterprises,narrow scope of financial services,and uneven industries of financial support. Finally,it came up with pertinent recommendations,including implementing diversified infrastructure financing modes,solving financing difficulty of small and medium sized enterprises through many channels,strengthening service level and expanding service scope of financial institutions,and changing the situation of uneven industry of financial support,in the hope of providing helpful references.展开更多
Pasteurella multocida is a leading cause of respiratory disorders in pigs.This study was designed to understand the genotypical and antimicrobial resistant characteristics of P.multocida from pigs in China.To achieve ...Pasteurella multocida is a leading cause of respiratory disorders in pigs.This study was designed to understand the genotypical and antimicrobial resistant characteristics of P.multocida from pigs in China.To achieve this,we briefly investigated 158 P.multocida isolates from pigs with respiratory disorders in China between 2019 and 2020.Genotyping through multiplex PCR assays assigned these 158 isolates into capsular genotypes A(60.13%,95/158),D(35.44%,56/158),F(4.43%,7/158),and/or lipopolysaccharide(LPS)genotypes L3(28.48%,45/158)and L6(66.46%,105/158).In addition,eight isolates(5.06%,8/158)were found to be nontypable using the LPS genotyping method.When combining the capsular genotypes and the LPS genotypes,D:L6(34.81%,55/158)and A:L6(31.65%,50/158)were the predominant genotypes,followed by A:L3(24.05%,38/158).PCR detection of virulence factor-encoding genes showed that over 80%of the isolates were positive for exbB,tonB,exbD,ompH,ptfA,fimA,sodA,sodC,fur,ompA,oma87,plpB,hsf-2,nanH and hgbB,suggesting the presence of these genes were broad characteristics of P.multocida.We also found approximately 63.92%(101/158),51.27%(81/158),8.86%(14/158),7.59%(12/158),3.16%(5/158),0.63%(1/158),and 0.63%(1/158)of the isolates grew well in media with the presence of colistin(4μg/mL),tetracycline(16μg/mL),tigecycline(1μg/mL),ampicillin(32μg/mL),chloramphenicol(32μg/mL),cefepime(16μg/mL),and ciprofloxacin(1μg/mL),respectively.This study contributes to the understanding of genotypes and antimicrobial resistance profile of P.multocida currently circulation in pigs of China.展开更多
Although solid-state lithium electrolytes have the potential to reduce the safety issues associated with organic liquid electrolytes,disadvantages such as low total conductivity,large interface impedance,and delaminat...Although solid-state lithium electrolytes have the potential to reduce the safety issues associated with organic liquid electrolytes,disadvantages such as low total conductivity,large interface impedance,and delamination of the interface due to cyclic stress still need to be addressed.The solid-state lithium-ion conductor Li_(0.33)La_(0.56)TiO_(3)(LLTO) was prepared via a hydrothermal route by using CTAB as templates in this paper.Perovskite LLTO with micro-porous channels was obtained and the total conductivity is comparable to the non-porous LLTO.Porous LLTO pellets are infiltrated with the non-porous LLTO precursor solution,and the total conductivities of the infiltrated porous LLTO are all higher than those without infiltration.After infiltration,the porous LLTO calcined at 600℃ achieves the highest total conductivity,7.88×10^(-5) S/cm.The fracture toughness of the infiltrated LLTO is higher than that of the non-porous LLTO.The results demonstrate a new way to prepare solid-state lithium-ion conductors with high ionic conductivity and great tolerance to cyclic stress.展开更多
Perovs kite-type Li_(0.33)La_(0.56)TiO_(3)(LLTO)shows greate r advantages than organic liquid electrolytes to be used in all-so lid-state lithium-ion batteries with high energy densities.Ionic liquid[BMIM][BF4]was use...Perovs kite-type Li_(0.33)La_(0.56)TiO_(3)(LLTO)shows greate r advantages than organic liquid electrolytes to be used in all-so lid-state lithium-ion batteries with high energy densities.Ionic liquid[BMIM][BF4]was used to improve the properties of Li_(0.33)La_(0.56)TiO_(3)by attrition milling in this study.The microstructure,crystallinity and lithium-ion conductivity of the samples were measured by scanning electron microscopy(SEM),X-ray diffraction(XRD),and impedance spectroscopy(IS).The total ionic conductivities of the samples LLTO+x wt%[BMIM][BF4]increase upon adding[BMIM][BF4]and the maximum conductivity reaches4.71×10^(-4)S/cm when x=12.5 wt%.The enhancement of the total conductivity is ascribed to the bridging role of the ionic liquid among grains,as evidenced by the low activation energy of 0.17-0.25 eV and the SEM observation.The Li+transference numbers of the hybrid samples are all lower than that of the pure LLTO,indicating the existence of electronic conductions.The hybrid mate rial with a mixed conductivity and good stability in the atmosphere can find uses in all-solid-state lithium-ion batteries to improve the interface contact between electrolytes and electrodes.展开更多
Tri-post insulators in gas-insulated transmission line(GIL)are usually fabricated with high mass fraction of micron aluminum oxide(Al_(2)O_(3)),which will unavoidably settle under the action of gravity during the prep...Tri-post insulators in gas-insulated transmission line(GIL)are usually fabricated with high mass fraction of micron aluminum oxide(Al_(2)O_(3)),which will unavoidably settle under the action of gravity during the preparation process and seriously affect the uniformity.A model of filler sedimentation in epoxy resin composite materials was proposed based on the particle size analysis and Stokes'Law.Some scaled tri-post insulators were prepared and tested by slicing.It is determined that the position of density concentration is the lower side of the two lower posts and the upper interface between the insulator and the conductor.The density ranges from 2.144 to 2.346 g/cm^(3).The dynamic fracture simulation model of insulator was established and it is found that the insulator fracture occurs at the interface of upper post/insert under radial load,which is verified by experiments.By comparing the influence of sprue position on the density distribution,it is found that the uniformity of insulators is increased by 13.7% by forward pouring compared with reverse pouring.This research develops an accurate method for simulating the filler sedimentation and the fracture process in epoxy-based insulators,which is helpful for the improvement of mechanical reliability of GIL.展开更多
In this paper,an angular position sensor(APS)designed for a resonant miniaturized scanning mirror(M-SM)is presented.The APS operates based on the principle of differential variable capacitance,significantly expanding ...In this paper,an angular position sensor(APS)designed for a resonant miniaturized scanning mirror(M-SM)is presented.The APS operates based on the principle of differential variable capacitance,significantly expanding the detectable bandwidth from a few hertz to several kilohertz.By modeling the motion characteristics,the sampling rates of the biaxial scanning angles are 1473.6 times and 539.4 times higher than those of conventional sensors.Initially,the motion characteristics model is presented as a simple harmonic motion,converting sampled capacitance into continuous capacitance.Subsequently,the nonparallel state of the M-SM and sensor is transformed into a parallel state through the space coordinate system transformation.Furthermore,a 2D nonlinear angle transfer function is developed to convert the differential capacitance into an angle,thereby mitigating the nonlinear errors resulting from large angles.Achieving an accuracy better than 0.014°,the measuring range expands from±0.5729°(±10 mrad)to±5.026°(±87 mrad).Additionally,the capturing mode and tracking mode are proposed to monitor real-time angular changes of the M-SM with an accuracy of 0.017°.High-precision APSs have enhanced beam pointing accuracy and resolution and can thereby be used to advance the development of laser components,including light detection and ranging(LiDAR).展开更多
Near-monodisperse NaYF4:Yb/Er nanoparticles(NPs) with controlled size, phases(α,β) and shapes(sphere, and hexagonal plate) were synthesized by adjusting the NaF to RE(RE = Y, Yb, Er) ratios, the reaction te...Near-monodisperse NaYF4:Yb/Er nanoparticles(NPs) with controlled size, phases(α,β) and shapes(sphere, and hexagonal plate) were synthesized by adjusting the NaF to RE(RE = Y, Yb, Er) ratios, the reaction temperature and time in the hot surfactant solutions(oleic acid, 1-octadecene) from the improved one-pot thermal decomposition metal trifluoroacetate, and the precursors were prepared via hydrothermal route. The growth kinetics of β-NaYF4 NPs includes several stages: nucleation, growth of aNaYF4, Ostwald ripening, size shrinkage and growth. The results prove that the temperatures are preferred to the phase transformation compared with the NaF content when other experimental conditions are unchanged. Our work will further facilitate the comprehension of the nucleation and growth mechanisms of the NPs, and provide guidance for their controlled synthesis.展开更多
The mode-locked laser diode has emerged as a promising candidate as a signal source for photonic radar systems,wireless data transmission, and frequency comb spectroscopy. They have the advantages of small size, low c...The mode-locked laser diode has emerged as a promising candidate as a signal source for photonic radar systems,wireless data transmission, and frequency comb spectroscopy. They have the advantages of small size, low cost,high reliability, and low power consumption, thanks to semiconductor technology. Mode-locked lasers based on silicon photonics advance these qualities by the use of highly advanced silicon manufacturing technology. This paper will begin by giving an overview of mode-locked laser diode literature, and then focus on mode-locked lasers on silicon. The dependence of mode-locked laser performance on design details is presented.展开更多
Quantum dot lasers are excellent on-chip light sources,offering high defect tolerance,low threshold,low temperature variation,and high feedback insensitivity.Yet a monolithic integration technique combining epitaxial ...Quantum dot lasers are excellent on-chip light sources,offering high defect tolerance,low threshold,low temperature variation,and high feedback insensitivity.Yet a monolithic integration technique combining epitaxial quantum dot lasers with passive waveguides has not been demonstrated and is needed for complex photonic integrated circuits.We present here,for the first time to our knowledge,a monolithc offset quantum dot integration platform that permits formation of a laser cavity utilizing both the robust quantum dot active region and the versatility of passive GaAs waveguide structures.This platform is substrate agnostic and therefore compatible with the quantum dot lasers directly grown on Si.As an illustration of the potential of this platform,we designed and fabricated a 20 GHz mode-locked laser with a dispersion-engineered on-chip waveguide mirror.Due to the dispersion compensation effect of the waveguide mirror,the pulse width of the mode-locked laser is reduced by a factor of 2.8.展开更多
The absorption behavior of Hg0 was studied experimentally by using sodium chlorite solution(NaClO2) as the absorbent in a bubble reactor.Primary influencing factors on removal efficiency of Hg0 such as NaClO2 concentr...The absorption behavior of Hg0 was studied experimentally by using sodium chlorite solution(NaClO2) as the absorbent in a bubble reactor.Primary influencing factors on removal efficiency of Hg0 such as NaClO2 concentration,pH,reaction temperature and the concentration of Hg0 were investigated.The results indicated that 72.91% of Hg0 removal efficiency could be achieved in acidic NaClO2 solution.The removal mechanism of Hg0 was proposed by analyzing of Hg2+ concentration in ab-sorption solution after reaction and comparing the electrode potentials between NaClO2 species and Hg2+/Hg0.The experimental results of mass transfer-reaction kinetics on oxidation of Hg0 by NaClO2 solution showed that with the increase of NaClO2 concentration and the decrease of pH value,the enhancement factor(E) and ratio of KG(Hg0)/kG(Hg0) increased and the liquid phase mass transfer resistance decreased,which is benefit to the mass transfer adsorption reaction.Although the increase of reaction temperature could improve the enhancement factor(E),but the ratio of KG(Hg0)/kG(Hg0) decreased;as a result,the liquid phase mass transfer resistance increased,therefore,the reaction rate for removal of Hg0 decreased.展开更多
In cirrhosis with ascites,hepatorenal syndrome(HRS)is a specific prerenal dysfunction unresponsive to fluid volume expansion.Acute-on-chronic liver failure(ACLF)comprises a group of clinical syndromes with multiple or...In cirrhosis with ascites,hepatorenal syndrome(HRS)is a specific prerenal dysfunction unresponsive to fluid volume expansion.Acute-on-chronic liver failure(ACLF)comprises a group of clinical syndromes with multiple organ failure and early high mortality.There are differences in the characterization of ACLF between the Eastern and Western medical communities.Patients with ACLF and acute kidney injury(AKI)have more structural injuries,contributing to confusion in diagnosing HRS-AKI.In this review,we discuss progress in the pathogenesis,diagnosis,and management of HRS-AKI,especially in patients with ACLF.Controversy regarding HRS-AKI in ACLF and acute liver failure,hepatic carcinoma,shock,sepsis,and chronic kidney disease is also discussed.Research on the treatment of HRS-AKI with ACLF needs to be more actively pursued to improve disease prognosis.展开更多
This work compares the four-wave mixing(FWM)effect in epitaxial quantum dot(QD)lasers grown on silicon with quantum well(QW)lasers.A comparison of theory and experiment results shows that the measured FWM coefficient ...This work compares the four-wave mixing(FWM)effect in epitaxial quantum dot(QD)lasers grown on silicon with quantum well(QW)lasers.A comparison of theory and experiment results shows that the measured FWM coefficient is in good agreement with theoretical predictions.The gain in signal power is higher for p-doped QD lasers than for undoped lasers,despite the same FWM coefficient.Owing to the near-zero linewidth enhancement factor,QD lasers exhibit FWM coefficients and conversion efficiency that are more than one order of magnitude higher than those of QW lasers.Thus,this leads to self-mode locking in QD lasers.These findings are useful for developing on-chip sources for photonic integrated circuits on silicon.展开更多
基金supported by National Natural Science Foundation of China(52170074).
文摘Air nanobubbles(A-NBs)were used to inhibit the brass corrosion in circulating cooling water for the first time in the study.The results of mass loss method and electrochemical method showed that A-NBs had the obvious corrosion inhibition effect.The inhibition rate reached 52%at 35℃.The impedance and surface characterization results of corrosion samples indicated that the corrosion inhibition mechanisms of A-NBs mainly included adsorption of corrosion ions,promoting the formation of the passivation film on metal surface and the formation of the bubble layer and scale film on metal surface.A-NBs are potential excellent corrosion inhibitors.
基金partially supported by the Major Program of the National Natural Science Foundation of China(No.22090034)the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Lithium cobalt oxide(LiCoO_(2))is proverbially employed as cathode materials of lithium-ion batteries attributed to the high theoretical capacity,and currently,it is developing towards higher cut-off voltages in the pursuit of higher energy density.However,it suffers from serious structural degradation and surface side reactions,in particular,at the voltage above 4.60 V,leading to rapid decay of the battery life.Taking into account the desirable oxygen buffering property and the fast ion mobility characteristic of cerium oxide fluoride,in this work,we prepared Ce&F co-modified LiCoO_(2)by using the precursors of Ce(NO_(3))_(3)·6H_(2)O and NH_(4)F,and evaluated the electrochemical performance under voltages exceeding 4.60 V.The results indicated that the modified samples have multiphase heterostructure of surface CeO_(2-x)and unique Ce-O-F solid solution phase.At 3.0–4.60 V and 25℃,the preferred sample LCO-0.5Ce-0.3F has a high initial discharge specific capacity of 221.9 mA h g^(-1)at 0.1 C,with the retention of 80.3%and 89.6%after 300 cycles at 1 and 5 C,comparing with the pristine LCO(56.4%and 22.6%).And at 3.0–4.65 V,its retention is 64.0%after 300 cycles at 1 C,versus 8.5%of the pristine LCO.Through structural characterizations and DFT calculations,it suggests that Ce^(4+)&F^(-)co-doping suppresses the H3 to H1/3 irreversible phase transition,stabilizes the lattice structure,and reduces the redox activity of the lattice oxygen by modulating the Co 3d–O 2p energy band,consequently improving the electrochemical performance of LiCoO_(2)at high voltages.
基金financially supported by the National Natural Science Foundation of China (81973604, 81803690 and 81703684)Special Funds from the Central Finance to Support the Development of Local Universities+12 种基金the National Natural Science Foundation Matching Project (2018PT02)the Innovative Talents Funding of Heilongjiang University of Chinese Medicine (2018RCD25)the Postdoctoral Initial Fund of Heilongjiang Province (UNPYSCT 2017219)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (UNPYSCT-2017215)the National Natural Science Foundation Matching Project (2017PT01)the Natural Science Foundation of Heilongjiang Province (H2015037)the Heilongjiang University of Chinese Medicine Doctoral Innovation Foundation (2014bs05)the Application Technology Research and Development Projects of Harbin Technology Bureau (2014RFQXJ149)the Heilongjiang Postdoctoral Scientific Research Developmental Fund (LBH-Q16210 and LBH-Q17161)the Heilongjiang University of Chinese Medicine Doctoral Innovation Foundation (2013bs04)the scientific research project of Heilongjiang Provincial Health Commission (20211313050171)Heilongjiang Touyan Innovation Team ProgramNational Famous Old Traditional Chinese Medecine Experts Inheritance Studio Construction Program of National Administration of TCM ([2022]No.75)
文摘Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects of LF.Fingerprints of ten batches of LF were established by UPLC-PDA.The inhibitory levels of AST and ALT were used as pharmacological indexes,and secoxyloganin,isochlorogenic acid A and isochlorogenic acid C were screened as hepatoprotective active compounds by grey relational analysis(GRA)and partial least squares regression analysis(PLSR).Caspase-3 was obtained by network pharmacology as a key target of hepatoprotective active compounds.Molecular docking is used to explore the interaction between small molecules and proteins.This work provided a general model of the combination of UPLC-PDA and hepatoprotective effect to study the spectrum-effect relationship of LF,which can be used to considerable methods and insight for the fundamental research of the material basis of similar healthcare food.
基金supported by the Science and Technology Plan Project of Hebei Province of China(16273703D)the Fundamental Research Funds for the Central Universities(2015ZD24,2017XS123)~~
文摘Vanadium-titanium-based catalysts are the most widely used industrial materials for NO_x removal from coal-fired power plants. Owing to their relatively poor low-temperature deNO_x activity, low thermal stability, insufficient Hg^0 oxidation activity, SO_2 oxidation, ammonia slip, and other disadvantages,modifications to traditional vanadium-titanium-based selective catalytic reduction(SCR)catalysts have been attempted by many researchers to promote their relevant performance. This article reviewed the research progress of modified vanadium-titanium-based SCR catalysts from seven aspects, namely,(1) improving low-temperature deNO_x efficiency,(2) enhancing thermal stability,(3) improving Hg^0 oxidation efficiency,(4) oxidizing slip ammonia,(5) reducing SO_2 oxidation,(6) increasing alkali resistance, and(7) others. Their catalytic performance and the influence mechanisms have been discussed in detail. These catalysts were also divided into different categories according to their modified components such as noble metals(e.g., silver, ruthenium), transition metals(e.g., manganese, iron, copper, zirconium, etc.), rare earth metals(e.g., cerium, praseodymium),and other metal chlorides(e.g., calcium chloride, copper chloride) and non-metals(fluorine,sulfur, silicon, nitrogen, etc.). The advantages and disadvantages of these catalysts were summarized.Based on previous studies and the author's point of view, doping the appropriate modified components is beneficial to further improve the overall performance of vanadium-titanium-based SCR catalysts. This has enormous development potential and is a promising way to realize the control of multiple pollutants on the basis of the existing flue gas treatment system.
基金supported by the China Postdoctoral Science Foundation(20100471451)the Science and Technology Foundation of State Key Laboratory of Underwater Measurement&Control Technology(9140C2603051003)
文摘In the methods of image thresholding segmentation, such methods based on two-dimensional (2D) histogram and optimal objective functions are important. However, when they are used for infrared image segmentation, they are weak in suppressing background noises and worse in segmenting targets with non-uniform gray level. The concept of 2D histogram shape modification is proposed, which is realized by target information prior restraint after enhancing target information using plateau histogram equalization. The formula of 2D minimum Renyi entropy is deduced for image segmentation, then the shape-modified 2D histogram is combined wfth four optimal objective functions (i.e., maximum between-class variance, maximum entropy, maximum correlation and minimum Renyi entropy) respectively for the appli- cation of infrared image segmentation. Simultaneously, F-measure is introduced to evaluate the segmentation effects objectively. The experimental results show that F-measure is an effective evaluation index for image segmentation since its value is fully consistent with the subjective evaluation, and after 2D histogram shape modification, the methods of optimal objective functions can overcome their original forms' deficiency and their segmentation effects are more or less improvements, where the best one is the maximum entropy method based on 2D histogram shape modification.
文摘Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward.Several approaches have been proposed and demonstrated to address this issue.In this paper,a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented.Representative device demonstrations,including ultra-narrow linewidthⅢ-Ⅴ/Si lasers,fully integratedⅢ-Ⅴ/Si/Si3N4 lasers,high-channel count mode locked quantum dot(QD)lasers,and high gain QD amplifiers will be covered.
基金Supported by Special Project of Fujian Provincial Department of Financ(K81MLV05A)
文摘Firstly,this paper discussed differences between traditional urbanization and new urbanization. Then,from current situations of financial support for new urbanization,it analyzed existing problems in financial support for new urbanization. The problems include difficulty in infrastructure financing,shortage of funds for small and medium sized enterprises,narrow scope of financial services,and uneven industries of financial support. Finally,it came up with pertinent recommendations,including implementing diversified infrastructure financing modes,solving financing difficulty of small and medium sized enterprises through many channels,strengthening service level and expanding service scope of financial institutions,and changing the situation of uneven industry of financial support,in the hope of providing helpful references.
基金This work was supported in part by the China Postdoctoral Foundation(grant 2020 T130232)the Key Laboratory of Livestock Disease Prevention of Guangdong Province and the Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province,Ministry of Agriculture and Rural Affairs,China(grant YDWS1901)Hubei Provincial Key R&D program.The funder had no role in the study design,data collection,data analysis,data interpretation,or writing of the manuscript.
文摘Pasteurella multocida is a leading cause of respiratory disorders in pigs.This study was designed to understand the genotypical and antimicrobial resistant characteristics of P.multocida from pigs in China.To achieve this,we briefly investigated 158 P.multocida isolates from pigs with respiratory disorders in China between 2019 and 2020.Genotyping through multiplex PCR assays assigned these 158 isolates into capsular genotypes A(60.13%,95/158),D(35.44%,56/158),F(4.43%,7/158),and/or lipopolysaccharide(LPS)genotypes L3(28.48%,45/158)and L6(66.46%,105/158).In addition,eight isolates(5.06%,8/158)were found to be nontypable using the LPS genotyping method.When combining the capsular genotypes and the LPS genotypes,D:L6(34.81%,55/158)and A:L6(31.65%,50/158)were the predominant genotypes,followed by A:L3(24.05%,38/158).PCR detection of virulence factor-encoding genes showed that over 80%of the isolates were positive for exbB,tonB,exbD,ompH,ptfA,fimA,sodA,sodC,fur,ompA,oma87,plpB,hsf-2,nanH and hgbB,suggesting the presence of these genes were broad characteristics of P.multocida.We also found approximately 63.92%(101/158),51.27%(81/158),8.86%(14/158),7.59%(12/158),3.16%(5/158),0.63%(1/158),and 0.63%(1/158)of the isolates grew well in media with the presence of colistin(4μg/mL),tetracycline(16μg/mL),tigecycline(1μg/mL),ampicillin(32μg/mL),chloramphenicol(32μg/mL),cefepime(16μg/mL),and ciprofloxacin(1μg/mL),respectively.This study contributes to the understanding of genotypes and antimicrobial resistance profile of P.multocida currently circulation in pigs of China.
基金Project supported by the Natural Science Foundation of Hebei Province,China(E2021502013)Key Research and Development Projects of Hebei Province.China(21373805D)。
文摘Although solid-state lithium electrolytes have the potential to reduce the safety issues associated with organic liquid electrolytes,disadvantages such as low total conductivity,large interface impedance,and delamination of the interface due to cyclic stress still need to be addressed.The solid-state lithium-ion conductor Li_(0.33)La_(0.56)TiO_(3)(LLTO) was prepared via a hydrothermal route by using CTAB as templates in this paper.Perovskite LLTO with micro-porous channels was obtained and the total conductivity is comparable to the non-porous LLTO.Porous LLTO pellets are infiltrated with the non-porous LLTO precursor solution,and the total conductivities of the infiltrated porous LLTO are all higher than those without infiltration.After infiltration,the porous LLTO calcined at 600℃ achieves the highest total conductivity,7.88×10^(-5) S/cm.The fracture toughness of the infiltrated LLTO is higher than that of the non-porous LLTO.The results demonstrate a new way to prepare solid-state lithium-ion conductors with high ionic conductivity and great tolerance to cyclic stress.
基金supported by the Natural Science Foundation of Hebei Province(E2021502013)Key Research and Development Projects of Hebei Province(21373805D)。
文摘Perovs kite-type Li_(0.33)La_(0.56)TiO_(3)(LLTO)shows greate r advantages than organic liquid electrolytes to be used in all-so lid-state lithium-ion batteries with high energy densities.Ionic liquid[BMIM][BF4]was used to improve the properties of Li_(0.33)La_(0.56)TiO_(3)by attrition milling in this study.The microstructure,crystallinity and lithium-ion conductivity of the samples were measured by scanning electron microscopy(SEM),X-ray diffraction(XRD),and impedance spectroscopy(IS).The total ionic conductivities of the samples LLTO+x wt%[BMIM][BF4]increase upon adding[BMIM][BF4]and the maximum conductivity reaches4.71×10^(-4)S/cm when x=12.5 wt%.The enhancement of the total conductivity is ascribed to the bridging role of the ionic liquid among grains,as evidenced by the low activation energy of 0.17-0.25 eV and the SEM observation.The Li+transference numbers of the hybrid samples are all lower than that of the pure LLTO,indicating the existence of electronic conductions.The hybrid mate rial with a mixed conductivity and good stability in the atmosphere can find uses in all-solid-state lithium-ion batteries to improve the interface contact between electrolytes and electrodes.
基金Science and Technology Project of SGCC,Grant/Award Number:SGSDJX00YJJS2100206。
文摘Tri-post insulators in gas-insulated transmission line(GIL)are usually fabricated with high mass fraction of micron aluminum oxide(Al_(2)O_(3)),which will unavoidably settle under the action of gravity during the preparation process and seriously affect the uniformity.A model of filler sedimentation in epoxy resin composite materials was proposed based on the particle size analysis and Stokes'Law.Some scaled tri-post insulators were prepared and tested by slicing.It is determined that the position of density concentration is the lower side of the two lower posts and the upper interface between the insulator and the conductor.The density ranges from 2.144 to 2.346 g/cm^(3).The dynamic fracture simulation model of insulator was established and it is found that the insulator fracture occurs at the interface of upper post/insert under radial load,which is verified by experiments.By comparing the influence of sprue position on the density distribution,it is found that the uniformity of insulators is increased by 13.7% by forward pouring compared with reverse pouring.This research develops an accurate method for simulating the filler sedimentation and the fracture process in epoxy-based insulators,which is helpful for the improvement of mechanical reliability of GIL.
基金financially supported by Beijing Advanced Innovation Center for Integrated Circuitsthe National Engineering Research Center for Offshore Windpower(HSFD22009).
文摘In this paper,an angular position sensor(APS)designed for a resonant miniaturized scanning mirror(M-SM)is presented.The APS operates based on the principle of differential variable capacitance,significantly expanding the detectable bandwidth from a few hertz to several kilohertz.By modeling the motion characteristics,the sampling rates of the biaxial scanning angles are 1473.6 times and 539.4 times higher than those of conventional sensors.Initially,the motion characteristics model is presented as a simple harmonic motion,converting sampled capacitance into continuous capacitance.Subsequently,the nonparallel state of the M-SM and sensor is transformed into a parallel state through the space coordinate system transformation.Furthermore,a 2D nonlinear angle transfer function is developed to convert the differential capacitance into an angle,thereby mitigating the nonlinear errors resulting from large angles.Achieving an accuracy better than 0.014°,the measuring range expands from±0.5729°(±10 mrad)to±5.026°(±87 mrad).Additionally,the capturing mode and tracking mode are proposed to monitor real-time angular changes of the M-SM with an accuracy of 0.017°.High-precision APSs have enhanced beam pointing accuracy and resolution and can thereby be used to advance the development of laser components,including light detection and ranging(LiDAR).
基金Project supported by the National Natural Science Foundation of China(2126016)the Science and Technology Innovation Guidance Project,Inner Mongolia,China(000-21090179)+2 种基金the Talents Project Inner Mongolia(CYYC:5026)the Opened Fund of the State Key Laboratory on integrated Optoelectronics(China IOSKL2013KF08)the Graduate Student Scientific Research Foundation of Inner Mongolia(S20161013505)
文摘Near-monodisperse NaYF4:Yb/Er nanoparticles(NPs) with controlled size, phases(α,β) and shapes(sphere, and hexagonal plate) were synthesized by adjusting the NaF to RE(RE = Y, Yb, Er) ratios, the reaction temperature and time in the hot surfactant solutions(oleic acid, 1-octadecene) from the improved one-pot thermal decomposition metal trifluoroacetate, and the precursors were prepared via hydrothermal route. The growth kinetics of β-NaYF4 NPs includes several stages: nucleation, growth of aNaYF4, Ostwald ripening, size shrinkage and growth. The results prove that the temperatures are preferred to the phase transformation compared with the NaF content when other experimental conditions are unchanged. Our work will further facilitate the comprehension of the nucleation and growth mechanisms of the NPs, and provide guidance for their controlled synthesis.
基金Defense Advanced Research Projects Agency(DARPA)EPHI and DODOS contracts
文摘The mode-locked laser diode has emerged as a promising candidate as a signal source for photonic radar systems,wireless data transmission, and frequency comb spectroscopy. They have the advantages of small size, low cost,high reliability, and low power consumption, thanks to semiconductor technology. Mode-locked lasers based on silicon photonics advance these qualities by the use of highly advanced silicon manufacturing technology. This paper will begin by giving an overview of mode-locked laser diode literature, and then focus on mode-locked lasers on silicon. The dependence of mode-locked laser performance on design details is presented.
基金Advanced Research Projects Agency-Energy(DE-AR0001039)。
文摘Quantum dot lasers are excellent on-chip light sources,offering high defect tolerance,low threshold,low temperature variation,and high feedback insensitivity.Yet a monolithic integration technique combining epitaxial quantum dot lasers with passive waveguides has not been demonstrated and is needed for complex photonic integrated circuits.We present here,for the first time to our knowledge,a monolithc offset quantum dot integration platform that permits formation of a laser cavity utilizing both the robust quantum dot active region and the versatility of passive GaAs waveguide structures.This platform is substrate agnostic and therefore compatible with the quantum dot lasers directly grown on Si.As an illustration of the potential of this platform,we designed and fabricated a 20 GHz mode-locked laser with a dispersion-engineered on-chip waveguide mirror.Due to the dispersion compensation effect of the waveguide mirror,the pulse width of the mode-locked laser is reduced by a factor of 2.8.
文摘The absorption behavior of Hg0 was studied experimentally by using sodium chlorite solution(NaClO2) as the absorbent in a bubble reactor.Primary influencing factors on removal efficiency of Hg0 such as NaClO2 concentration,pH,reaction temperature and the concentration of Hg0 were investigated.The results indicated that 72.91% of Hg0 removal efficiency could be achieved in acidic NaClO2 solution.The removal mechanism of Hg0 was proposed by analyzing of Hg2+ concentration in ab-sorption solution after reaction and comparing the electrode potentials between NaClO2 species and Hg2+/Hg0.The experimental results of mass transfer-reaction kinetics on oxidation of Hg0 by NaClO2 solution showed that with the increase of NaClO2 concentration and the decrease of pH value,the enhancement factor(E) and ratio of KG(Hg0)/kG(Hg0) increased and the liquid phase mass transfer resistance decreased,which is benefit to the mass transfer adsorption reaction.Although the increase of reaction temperature could improve the enhancement factor(E),but the ratio of KG(Hg0)/kG(Hg0) decreased;as a result,the liquid phase mass transfer resistance increased,therefore,the reaction rate for removal of Hg0 decreased.
基金supported by the Scientific Research Project of Beijing You’an Hospital[CCMU 2019]the China Primary Health Care Foundation–Youan Foundation of Liver Disease and AIDS[BJYAYY-GG2019-01].
文摘In cirrhosis with ascites,hepatorenal syndrome(HRS)is a specific prerenal dysfunction unresponsive to fluid volume expansion.Acute-on-chronic liver failure(ACLF)comprises a group of clinical syndromes with multiple organ failure and early high mortality.There are differences in the characterization of ACLF between the Eastern and Western medical communities.Patients with ACLF and acute kidney injury(AKI)have more structural injuries,contributing to confusion in diagnosing HRS-AKI.In this review,we discuss progress in the pathogenesis,diagnosis,and management of HRS-AKI,especially in patients with ACLF.Controversy regarding HRS-AKI in ACLF and acute liver failure,hepatic carcinoma,shock,sepsis,and chronic kidney disease is also discussed.Research on the treatment of HRS-AKI with ACLF needs to be more actively pursued to improve disease prognosis.
基金Basic and Applied Basic Research Foundation of Guangdong Province(2021A1515110076)Center for Integrated Nanotechnologies,an Office of Science User Facility operated for the U.S.Department of Energy(DOE)Office of Science by Los Alamos National Laboratory(2021BC0057)DARPA PIPES(HR0011-19-C-0083).
文摘This work compares the four-wave mixing(FWM)effect in epitaxial quantum dot(QD)lasers grown on silicon with quantum well(QW)lasers.A comparison of theory and experiment results shows that the measured FWM coefficient is in good agreement with theoretical predictions.The gain in signal power is higher for p-doped QD lasers than for undoped lasers,despite the same FWM coefficient.Owing to the near-zero linewidth enhancement factor,QD lasers exhibit FWM coefficients and conversion efficiency that are more than one order of magnitude higher than those of QW lasers.Thus,this leads to self-mode locking in QD lasers.These findings are useful for developing on-chip sources for photonic integrated circuits on silicon.