HPLC-ELSD同时测定腺梗豨莶草中6个二萜成分的含量

为了研究腺梗豨莶草中6个二萜成分(对映海松烯型二萜:奇任醇、Hythiemoside B和豨莶精醇;对映贝壳杉烷型二萜:对映-17,18-二羟基-贝壳杉烷-19-羧酸、对映-16β,17-二羟基-贝壳杉烷-19-羧酸和对映-16α氢-贝壳杉烷-17,19-二羧酸)的含量,本试验建立了高效液相色谱法-蒸发光散射检测器(HPLC-ELSD)同时测定二萜类化合物含量。样品粉碎过筛加甲醇和乙酸乙酯回流提取,蒸发减压除去溶剂,甲醇溶解,0.45μm滤膜滤过,取续滤液进行测定。色谱条件:色谱柱为Waters Symmetry Shield^(TM)RP18柱(250 mm×4.6 mm,5μm),流动相为0.3%甲酸水溶液-乙腈(v/v),梯度洗脱,流速为1.0 mL/min。蒸发光散射检测器漂移管温度为103℃,雾化气流速为3.0 L/min。应用该方法测定腺梗豨莶草样品不同部位中6个二萜类化合物的含量,同时比较叶、枝、茎中对映海松烯型二萜、对映贝壳杉型二萜和总二萜含量的差异。结果显示,6个二萜成分在其线性范围内线性关系良好(r≥0.9992);日内和日间精密度相对标准偏差(RSD)均小于3.5%;回收率介于96.5%~101.5%,RSD均小于2.3%;腺梗豨莶草不同部位(叶、枝、茎)的二萜类化合物含量差异较大。结果表明,本试验所建立的HPLC-ELSD方法简便、准确、重复性好,为腺梗豨莶草药材全面的质量评价和临床应用中最佳药用部位的选择提供了参考。

HPLC-ELSD法测定龙泽熊胆胶囊中牛磺熊去氧胆酸和牛磺鹅去氧胆酸的含量

目的:以牛磺熊去氧胆酸和牛磺鹅去氧胆酸为指标,建立龙泽熊胆胶囊中熊胆粉的含量测定方法。方法:采用高效液相色谱串联蒸发光检测器,色谱柱为ChromCore AQ C 18(4.6 mm×250 mm,5μm),乙腈(A)-5 mmol•L^(-1)醋酸铵溶液(B)为流动相,梯度洗脱(0~40 min,25%A;40~50 min,25%A→29%A;50~80 min,29%A;80~100 min,29%A→40%A),流速1.0 mL•min^(-1),柱温30℃,ELSD漂移管温度110℃,氮流量2.5L•min^(-1)。结果:牛磺熊去氧胆酸进样量在1.069~9.57μg内、牛磺鹅去氧胆酸进样量在0.74046~7.40464μg内,进样量的对数与峰面积的对数呈良好的线性关系;仪器精密度、重复性、稳定性试验的RSD<2.0%;经低、中、高3个浓度的准确度试验考察,牛磺熊去氧胆酸的回收率为95.2%~97.7%,牛磺鹅去氧胆酸的回收率为91.9%~95.9%。测定样品42批次,牛磺熊去氧胆酸和牛磺鹅去氧胆酸的含量分别为0.18~0.43、0.10~0.44 mg•粒^(-1)。结论:本法适用于龙泽熊胆胶囊中熊胆粉的质量控制,可为完善龙泽熊胆胶囊的质量标准提供科学的依据。

高效液相-蒸发光散射检测器(HPLC-ELSD)测定红参中的精氨酸单糖苷(AF)及精氨酸双糖苷(AFG)含量

目的建立一种同时测定人参加工品中精氨酸单糖苷(AF)和精氨酸双糖苷(AFG)含量的方法。[方法]用PrevailTMC18column(4.6 mm×250 mm,5μm)色谱柱进行检测。流动相A:色谱乙腈,流动相B:5.0mmol/L七氟丁酸的0.7%三氟醋酸溶液。色谱条件为[0%A(0 min);0%A(5 min);15%A(8 min);35%A(25 min)];流速0.8 mL/min;漂移管温度为115℃;气体流量3.2 L/min。[结果]AF和AFG的检测限分别为0.015和0.010 mg/mL;线性关系相关系数分别为,AF:0.9997,AFG:0.9999,表明线性关系良好。AF和AFG检测的精密度,重复性,稳定性以及回收率的相对标准偏差分别为0.43%&0.37%,0.43%&0.55%,0.43%&0.49%,0.45%&0.15%。AF和AFG检测的回收率分别为99.5%&100%,表明方法稳定。经检测,高丽红参,中国红参和生晒参中AF含量分别为0.74%,0.91%和1.14%,AFG含量分别为6.69%,5.12%和0.85%。[结论]这种方法成功用于高丽红参,中国红参及生晒参中AF及AFG的检测;且红参中AF和AFG含量明显高于生晒参。该方法测定结果可靠,缩短了测定时间,较少杂质干扰。但因为本研究考察氨基酸种类较少,当衍生物种类较多时,仍需进一步考察其分离度。

PTW Detector7293种剂量验证方法在调强放射治疗中的对比研究

目的 :对比PTW Detector729 3种验证方法在调强放射治疗(intensity modulated radiation therapy,IMRT)剂量验证中的差异。方法:回顾性选取2022年1—12月于某院完成放射治疗的鼻咽癌、肺癌、乳腺癌、宫颈癌和全脑放射治疗患者共50例,使用PTW Detector729二维电离室矩阵配合PTW RW3固体水与PTW Ocavius 4D旋转模体对50例患者的IMRT计划分别进行归零机架角2D剂量验证、实际机架角2D剂量验证和实际机架角3D剂量验证。将剂量评估阈值设为10%,统计3种验证方法在3%/1 mm、2%/2 mm、3%/2 mm和3%/3 mm 4种评估标准下的γ通过率。采用SPSS 22.0统计学软件进行数据分析。结果:在10%剂量评估阈值标准下,归零机架角2D剂量验证的γ通过率最高,差异有统计学意义(P<0.05);实际机架角2D剂量验证的γ通过率高于实际机架角3D剂量验证,差异有统计学意义(P<0.05)。3种验证方法的γ通过率在3%/1 mm、2%/2 mm、3%/2 mm和3%/3 mm 4种标准下逐渐升高,且在3%/2 mm标准下均超过90%,结果满足临床放射治疗要求。结论:3种验证方法的验证结果均能达到IMRT剂量验证实践指南要求,根据IMRT开展情况选择合适的验证方法,对确保治疗方案安全、有效实施具有重要意义。

High-speed performance self-powered short wave ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)

High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in detail.Theκ(ε)-Ga_(2)O_(3)layers were deposited by the halide vapor phase epitaxy on patterned GaN templates with sapphire substrates.The spectral dependencies of the photoelectric properties of struc-tures were analyzed in the wavelength interval 200-370 nm.The maximum photo to dark current ratio,responsivity,detectiv-ity and external quantum efficiency of structures were determined as:180.86 arb.un.,3.57 A/W,1.78×10^(12) Hz^(0.5)∙cm·W^(-1) and 2193.6%,respectively,at a wavelength of 200 nm and an applied voltage of 1 V.The enhancement of the photoresponse was caused by the decrease in the Schottky barrier at the Pt/κ(ε)-Ga_(2)O_(3)interface under ultraviolet exposure.The detectors demon-strated could functionalize in self-powered mode due to built-in electric field at the Pt/κ(ε)-Ga_(2)O_(3)interface.The responsivity and external quantum efficiency of the structures at a wavelength of 254 nm and zero applied voltage were 0.9 mA/W and 0.46%,respectively.The rise and decay times in self-powered mode did not exceed 100 ms.

Low-noise and low-power pixel sensor chip for gas pixel detectors

Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in 2021.The pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μm.The array is divided into 16 subarrays,with pixels of 400 rows×32 columns per subarray.Each pixel incorporates two charge sensors:a diode sensor and a Topmetal sensor.The in-pixel circuit primarily consists of a charge-sensitive amplifier for energy measurements,a discriminator with a peak-holding circuit,and a time-to-amplitude converter for time-of-arrival measurements.The pixel of Topmetal-M2 has a charge input range of~0-3 k e-,a voltage output range of~0-180 mV,and a charge-voltage conversion gain of~59.56μV∕e-.The average equivalent noise charge of Topmetal-M2,which includes the readout electronic system noise,is~43.45 e-.In the scanning mode,the time resolution of Topmetal-M2 is 1 LSB=1.25μs,and the precision is^()7.41μs.At an operating voltage of 1.5 V,Topmetal-M2 has a power consumption of~49 mW∕cm~2.In this article,we provide a comprehensive overview of the chip architecture,pixel working principles,and functional behavior of Topmetal-M2.Furthermore,we present the results of preliminary tests conducted on Topmetal-M2,namely,alpha-particle and soft X-ray tests.

HPLC-ELSD法测定硫酸庆大霉素碳酸铋胶囊中庆大霉素C组分及有关物质含量

目的为硫酸庆大霉素碳酸铋胶囊中庆大霉素C组分及有关物质建立质控方法。方法采用HPLC-ELSD方法,色谱柱:GRACEApollo C18柱(250 mm×4.6 mm,5μm);流动相:0.2 mol/L三氟乙酸溶液-甲醇(96:4,V/V),流速0.6 mL/min;柱温30℃;进样量20μL;Waters低温分流型蒸发光散射检测器,载气流量40 psi,漂移管温度55℃。结果所建方法通过方法学验证,庆大霉素C组分与各杂质间分离完全,庆大霉素、西索米星和小诺霉素分别在0.5~6 mg/mL、25~100μg/mL和25~100μg/mL的浓度范围内,各浓度的对数值与对应色谱峰面积的对数值呈现出良好的线性。采用所建方法对市售16家生产企业43批次硫酸庆大霉素碳酸铋胶囊样品进行测定,获得该制剂产品中各组分及有关物质的数据。结论所建方法是在中国药典方法基础上优化并验证适用于硫酸庆大霉素碳酸铋胶囊C组分及有关物质的含量测定,方法简便准确,专属性强,稳定性好。由获得的实验数据可知,该复方制剂中C组分及有关物质的含量在各厂家间或同厂家不同批次间差异显著,可能存在影响用药安全的潜在隐患,建议在该剂型质量标准中增加相关质控项。

CVTD: A Robust Car-Mounted Video Text Detector

Text perception is crucial for understanding the semantics of outdoor scenes,making it a key requirement for building intelligent systems for driver assistance or autonomous driving.Text information in car-mounted videos can assist drivers in making decisions.However,Car-mounted video text images pose challenges such as complex backgrounds,small fonts,and the need for real-time detection.We proposed a robust Car-mounted Video Text Detector(CVTD).It is a lightweight text detection model based on ResNet18 for feature extraction,capable of detecting text in arbitrary shapes.Our model efficiently extracted global text positions through the Coordinate Attention Threshold Activation(CATA)and enhanced the representation capability through stacking two Feature Pyramid Enhancement Fusion Modules(FPEFM),strengthening feature representation,and integrating text local features and global position information,reinforcing the representation capability of the CVTD model.The enhanced feature maps,when acted upon by Text Activation Maps(TAM),effectively distinguished text foreground from non-text regions.Additionally,we collected and annotated a dataset containing 2200 images of Car-mounted Video Text(CVT)under various road conditions for training and evaluating our model’s performance.We further tested our model on four other challenging public natural scene text detection benchmark datasets,demonstrating its strong generalization ability and real-time detection speed.This model holds potential for practical applications in real-world scenarios.

Flexibility potential of Cs_(2)BX_(6)(B=Hf,Sn,Pt,Zr,Ti;X=I,Br,Cl)with application in photovoltaic devices and radiation detectors

As interest in double perovskites is growing,especially in applications like photovoltaic devices,understanding their mechanical properties is vital for device durability.Despite extensive exploration of structure and optical properties,research on mechanical aspects is limited.This article builds a vacancyordered double perovskite model,employing first-principles calculations to analyze mechanical,bonding,electronic,and optical properties.Results show Cs_(2)Hfl_(6),Cs_(2)SnBr_(6),Cs_(2)SnI_(6),and Cs_(2)PtBr_(6)have Young's moduli below 13 GPa,indicating flexibility.Geometric parameters explain flexibility variations with the changes of B and X site composition.Bonding characteristic exploration reveals the influence of B and X site electronegativity on mechanical strength.Cs_(2)SnBr_(6)and Cs_(2)PtBr_(6)are suitable for solar cells,while Cs_(2)HfI_(6)and Cs_(2)TiCl_(6)show potential for semi-transparent solar cells.Optical property calculations highlight the high light absorption coefficients of up to 3.5×10^(5) cm^(-1)for Cs_(2)HfI_(6)and Cs_(2)TiCl_(6).Solar cell simulation shows Cs_(2)PtBr_(6)achieves 22.4%of conversion effciency.Cs_(2)ZrCl_(6)holds promise for ionizing radiation detection with its 3.68 eV bandgap and high absorption coefficient.Vacancy-ordered double perovskites offer superior flexibility,providing valuable insights for designing stable and flexible devices.This understanding enhances the development of functional devices based on these perovskites,especially for applications requiring high stability and flexibility.

Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a distance.In this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)detector.The imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded mask.An EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager performance.The difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position resolution.The position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 cm.The DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution images.The unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image denoising.This method can effectively reduce image noise caused by poor DOI detector position resolution.The vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

Method for detector description conversion from DD4hep to Filmbox

DD4hep serves as a generic detector description toolkit recommended for offline software development in next-generation high-energy physics(HEP)experiments.Conversely,Filmbox(FBX)stands out as a widely used 3D modeling file format within the 3D software industry.In this paper,we introduce a novel method that can automatically convert complex HEP detector geometries from DD4hep description into 3D models in the FBX format.The feasibility of this method was dem-onstrated by its application to the DD4hep description of the Compact Linear Collider detector and several sub-detectors of the super Tau-Charm facility and circular electron-positron collider experiments.The automatic DD4hep–FBX detector conversion interface provides convenience for further development of applications,such as detector design,simulation,visualization,data monitoring,and outreach,in HEP experiments.

Self-powered UVC detectors based on α-Ga_(2)O_(3) with enchanted speed performance

Detectors were developed for detecting irradiation in the short-wavelength ultraviolet(UVC)interval using high-quality single-crystallineα-Ga_(2)O_(3) films with Pt interdigital contacts.The films ofα-Ga_(2)O_(3) were grown on planar sapphire substrates with c-plane orientation using halide vapor phase epitaxy.The spectral dependencies of the photo to dark current ratio,responsivity,external quantum efficiency and detectivity of the structures were investigated in the wavelength interval of 200−370 nm.The maximum of photo to dark current ratio,responsivity,external quantum efficiency,and detectivity of the structures were 1.16×10^(4) arb.un.,30.6 A/W,1.65×10^(4)%,and 6.95×10^(15) Hz^(0.5)·cm/W at a wavelength of 230 nm and an applied voltage of 1 V.The high values of photoelectric properties were due to the internal enhancement of the photoresponse associated with strong hole trapping.Theα-Ga_(2)O_(3) film-based UVC detectors can function in self-powered operation mode due to the built-in electric field at the Pt/α-Ga_(2)O_(3) interfaces.At a wavelength of 254 nm and zero applied voltage,the structures exhibit a responsivity of 0.13 mA/W and an external quantum efficiency of 6.2×10^(−2)%.The UVC detectors based on theα-Ga_(2)O_(3) films demonstrate high-speed performance with a rise time of 18 ms in self-powered mode.

FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors

Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,China.The experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 ms.At count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV.

Gas microchannel plate-pixel detector for X-ray polarimetry

POLAR-2 is a gamma-ray burst(GRB)polarimeter that is designed to study the polarization in GRB radiation emissions,aiming to improve our knowledge of related mechanisms.POLAR-2 is expected to utilize an on-board polarimeter that is sensitive to soft X-rays(2-10 keV),called low-energy polarization detector.We have developed a new soft X-ray polari-zation detector prototype based on gas microchannel plates(GMCPs)and pixel chips(Topmetal).The GMCPs have bulk resistance,which prevents charging-up effects and ensures gain stability during operation.The detector is composed of low outgassing materials and is gas-sealed using a laser welding technique,ensuring long-term stability.A modulation factor of 41.28%±0.64% is obtained for a 4.5 keV polarized X-ray beam.A residual modulation of 1.96%±0.58% at 5.9 keV is observed for the entire sensitive area.

Construction and performance test of charged particle detector array for MATE

A charged particle array named MATE-PA,which serves as an auxiliary detector system for a Multi-purpose Active-target Time projection chamber used in nuclear astrophysical and exotic beam Experiments(MATE),was constructed.The array comprised of 20 single-sided strip-silicon detectors covering approximately 10%of the solid angle.The detectors facilitated the detection of reaction-induced charged particles that penetrate the active volume of the MATE.The performance of MATE-PA has been experimentally studied using an alpha source and a 36-MeV 14 N beam injected into the MATE chamber on the radioactive ion beam line in Lanzhou(RIBLL).The chamber was filled with a gas mixture of 95%4 He and 5%CO_(2) at a pressure of 500 mbar.The results indicated good separation of light-charged particles using the forward double-layer silicon detectors of MATE-PA.The energy resolution of the Si detectors was deduced to be approximately 1%(σ)for an energy loss of approximately 10 MeV caused by theαparticles.The inclusion of MATE-PA improves particle identification and increases the dynamic range of the kinetic energy of charged particles,particularly that of theαparticles,up to approximately 15 MeV.

Structural design of mid-infrared waveguide detectors based on InAs/GaAsSb superlattice

In the realm of near-infrared spectroscopy,the detection of molecules has been achieved using on-chip waveguides and resonators.In the mid-infrared band,the integration and sensitivity of chemical sensing chips are often constrained by the reliance on off-chip light sources and detectors.In this study,we demonstrate an InAs/GaAsSb superlattice mid-infrared waveguide integrated detector.The GaAsSb waveguide layer and the InAs/GaAsSb superlattice absorbing layer are connected through evanescent coupling,facilitating efficient and highquality detection of mid-infrared light with minimal loss.We conducted a simulation to analyze the photoelectric characteristics of the device.Additionally,we investigated the factors that affect the integration of the InAs/GaAs⁃Sb superlattice photodetector and the GaAsSb waveguide.Optimal thicknesses and lengths for the absorption lay⁃er are determined.When the absorption layer has a thickness of 0.3μm and a length of 50μm,the noise equiva⁃lent power reaches its minimum value,and the quantum efficiency can achieve a value of 68.9%.The utilization of waveguide detectors constructed with Ⅲ-Ⅴ materials offers a more convenient means of integrating mid-infra⁃red light sources and achieving photoelectric detection chips.

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance evaluation.When the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and detectors.This study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam energies.Simulations were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope layouts.The simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be ignored.Compared with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

Probability-Enhanced Anchor-Free Detector for Remote-Sensing Object Detection

Anchor-free object-detection methods achieve a significant advancement in field of computer vision,particularly in the realm of real-time inferences.However,in remote sensing object detection,anchor-free methods often lack of capability in separating the foreground and background.This paper proposes an anchor-free method named probability-enhanced anchor-free detector(ProEnDet)for remote sensing object detection.First,a weighted bidirectional feature pyramid is used for feature extraction.Second,we introduce probability enhancement to strengthen the classification of the object’s foreground and background.The detector uses the logarithm likelihood as the final score to improve the classification of the foreground and background of the object.ProEnDet is verified using the DIOR and NWPU-VHR-10 datasets.The experiment achieved mean average precisions of 61.4 and 69.0 on the DIOR dataset and NWPU-VHR-10 dataset,respectively.ProEnDet achieves a speed of 32.4 FPS on the DIOR dataset,which satisfies the real-time requirements for remote-sensing object detection.

A new calibration method for radon detector in seismic systems

Radon observation is an important measurement item of seismic precursor network observation.The radon detector calibration is a key technical link for ensuring radon observation accuracy.At present,the radon detector calibration in seismic systems in China is faced with a series of bottleneck problems,such as aging and scrap,acquisition difficulties,high supervision costs,and transportation limitations of radon sources.As a result,a large number of radon detectors cannot be accurately calibrated regularly,seriously affecting the accuracy and reliability of radon observation data in China.To solve this problem,a new calibration method for radon detectors was established.The advantage of this method is that the dangerous radioactive substance,i.e.,the radon source,can be avoided,but only“standard instruments”and water samples with certain dissolved radon concentrations can be used to realize radon detector calibration.This method avoids the risk of radioactive leakage and solves the current widespread difficulties and bottleneck of radon detector calibration in seismic systems in China.The comparison experiment with the traditional calibration method shows that the error of the calibration coefficient obtained by the new method is less than 5%compared with that by the traditional method,which meets the requirements of seismic observation systems,confirming the reliability of the new method.This new method can completely replace the traditional calibration method of using a radon source in seismic systems.

Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation

The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is proposed as the early stage of the GRAND project,consisting of a hybrid array of radio antennas and scintillator detectors.The latter,as a mature and traditional detector,is used to cross-check the nature of the candidate events selected from radio observations.In this study,we developed a simulation software called G4GRANDProto300,based on the Geant4 software package,to optimize the spacing of the scintillator detector array and to investigate its effective area.The analysis was conducted at various zenith angles under different detector spacings,including 300,500,600,700,and 900 m.Our results indicate that,for large zenith angles used to search for cosmic-ray in the GRAND project,the optimized effective area is with a detector spacing of 500 m.The G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work.