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Langmuir probe diagnostics in multi-Maxwellian EEDF plasmas
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作者 YIP Chi-shung JIN Chenyao +1 位作者 JIANG Di ZHANG Wei 《推进技术》 北大核心 2025年第6期254-274,共21页
This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwel... This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements. 展开更多
关键词 Plasma diagnostics Langmuir probes EEDFs I-V characteristics Electron temperature
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High performance streaked X-ray spectrometer for research of laser-produced plasmas
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作者 Guo Luting Wei Minxi +8 位作者 Hu Xin Deng Keli Chen Tao Deng Bo Zhang Lu Zhao Yang Li Jin Xiao Shaoqiu Liu Shenye 《强激光与粒子束》 EI CAS CSCD 北大核心 2016年第2期52-55,共4页
In order to mitigate the effect of the strong electromagnetic pulse, which produces laser-plasma interactions, we designed a new streaked X-ray spectrometer (SXS) enclosed within a well-sealed, electromag- netic int... In order to mitigate the effect of the strong electromagnetic pulse, which produces laser-plasma interactions, we designed a new streaked X-ray spectrometer (SXS) enclosed within a well-sealed, electromag- netic interference-free cavity. The SXS can cover a wide selection of spectral windows using interchangeable Bragg crystals and by appropriate adjustment of the Bragg angle. The SXS has been used to observe time-re- solved X-ray spectrum in the 2.5 keV to 3.5 keV photon-energy range, resulting in a demonstrated spectral res- olution of about 13 at 2960 eV with a time resolution of 10 ps. The observed time and spectral resolutions dem- onstrate the applicability of the SXS for studies of laser-produced plasmas. 展开更多
关键词 streaked X-RAY SPECTROMETER X-RAY SPECTRUM plasmas BRAGG CRYSTAL
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Piecewise linear recursive convolution FDTD method for magnetized plasmas 被引量:4
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作者 Liu Song Zhong Shuangying Liu Shaobin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期290-295,共6页
The piecewise linear recursive convolution (PLRC) finite-different time-domain (FDTD) method greatly improves accuracy over the original recursive convolution (RC) FDTD approach but retains its speed and efficie... The piecewise linear recursive convolution (PLRC) finite-different time-domain (FDTD) method greatly improves accuracy over the original recursive convolution (RC) FDTD approach but retains its speed and efficiency advantages. A PLRC-FDTD formulation for magnetized plasma which incorporates both anisotropy and frequency dispersion at the same time is presented, enabled the transient analysis of magnetized plasma media. The technique is illustrated by numerical simulations the reflection and transmission coefficients through a magnetized plasma layer. The results show that the PLRC-FDTD method has significantly improved the accuracy over the original RC method. 展开更多
关键词 electromagnetic wave FDTD methods piecewise linear recursive convolution magnetized plasma.
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Dust Acoustic Wave in Dusty Plasmas With Streaming Ions Under Ultraviolet Irradiation
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作者 REN Liwen WANG Chi 《空间科学学报》 CAS CSCD 北大核心 2012年第2期191-196,共6页
The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge va... The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge variation is taken into account.It is shown that the ultraviolet irradiation can significantly lower the magnitude of the dust negative charge,and ion streaming velocity firstly raise the magnitude of the dust negative charge and then lower it.With the growth of(Ultraviolet) UV photo flux or ion streaming velocity,the phase velocity and width of the solitary waves decrease, whereas its amplitude increases. 展开更多
关键词 Dusty plasma Solitary wave Ultraviolet irradiation Streaming ion
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ESCRT Mechanism-mediated Repair of Plasma Membrane Damage Induced by Regulatory Cell Death
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作者 FENG Tian-Yang DENG Le +2 位作者 XU Gou LI Li GUO Miao-Miao 《生物化学与生物物理进展》 北大核心 2025年第5期1099-1112,共14页
The plasma membrane(PM)plays an essential role in maintaining cell homeostasis,therefore,timely and effective repair of damage caused by factors such as mechanical rupture,pore-forming toxins,or pore-forming proteins ... The plasma membrane(PM)plays an essential role in maintaining cell homeostasis,therefore,timely and effective repair of damage caused by factors such as mechanical rupture,pore-forming toxins,or pore-forming proteins is crucial for cell survival.PM damage induces membrane rupture and stimulates an immune response.However,damage resulting from regulated cell death processes,including pyroptosis,ferroptosis,and necroptosis,cannot be repaired by simple sealing mechanisms and thus,requires specialized repair machinery.Recent research has identified a PM repair mechanism of regulated cell death-related injury,mediated by the endosomal sorting complexes required for transport(ESCRT)machinery.Here,we review recent progress in elucidating the ESCRT machinery-mediated repair mechanism of PM injury,with particular focus on processes related to regulated cell death.This overview,along with continued research in this field,may provide novel insights into therapeutic targets for diseases associated with dysregulation of regulated cell death pathways. 展开更多
关键词 ESCRT PYROPTOSIS ferroptosis NECROPTOSIS plasma membrane repair
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Cotton seed management:traditional and emerging treatment approaches for enhanced productivity
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作者 MYLSAMY Preethi TAMILMANI Eevera +2 位作者 VENUGOPAL Rajanbabu MURUGAIYAN Senthilkumar RANGANATHAN Umarani 《Journal of Cotton Research》 2025年第1期143-161,共19页
Cotton,a crucial commercial fibre crop,depends heavily on seed-associated characteristics like germination rate,vigour,and resistance to post-harvest deterioration for both production and lint quality.Serious cellular... Cotton,a crucial commercial fibre crop,depends heavily on seed-associated characteristics like germination rate,vigour,and resistance to post-harvest deterioration for both production and lint quality.Serious cellular damage dur-ing post-harvest processes such as delinting,prolonged seedling emergence periods,decreased viability,increased susceptibility to infections,and lipid peroxidation during storage pose serious problems to seed quality.The perfor-mance of seeds and total crop productivity are adversely affected by these problems.Traditional methods of seed improvement,like physical scarification and seed priming,have demonstrated promise in raising cotton seed vigour and germination rates.Furthermore,modern approaches including plasma therapies,magnetic water treatments,and nanotechnology-based treatments have shown promise in improving seed quality and reducing environmen-tal stresses.By offering sustainable substitutes for conventional approaches,these cutting-edge procedures lessen the need for fungicides and other agrochemicals that pollute the environment.This review explores various con-ventional and emerging strategies to address the detrimental factors impacting cotton seed quality.It emphasizes the importance of integrating classical and advanced approaches to enhance germination,ensure robust crop estab-lishment,and achieve higher yields.In addition to promoting sustainable cotton production,this kind of integration helps preserve the ecosystem and create resilient farming methods. 展开更多
关键词 Cotton Seed vigour Physical scarification Seed priming Plasma treatment Magnetic water treatments Nanotechnology-based treatments
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Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate 被引量:3
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作者 Haotian Jian Guoqiang Zheng +4 位作者 Lejian Chen Zheng Ning Guofu Yin Peng Zhu Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期222-231,共10页
Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig... Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success. 展开更多
关键词 Exploding foil initiator PDV Plasma spectrum Ignition mechanism Boron potassium nitrate
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Investigation on the exploding foil initiators ignition enhanced by explosion-electricity coupling 被引量:1
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作者 Songmao Zhao Haotian Jian +3 位作者 Ke Wang Zheng Ning Peng Zhu Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第12期1-11,共11页
Explosion-electricity coupling(EEC) is a technical method to induce electric energy into the plasma material produced by explosion to improve the output of explosion.Exploding foil initiator(EFI) which could produce p... Explosion-electricity coupling(EEC) is a technical method to induce electric energy into the plasma material produced by explosion to improve the output of explosion.Exploding foil initiator(EFI) which could produce plasma during electric explosion can serve as a good carrier for studying the EEC.To investigate the enhancement ability and mechanism of EEC in EFI ignition performance,a kind of EFI chips which could realize the EEC effect was designed and fabricated to observe the characteristics of current and voltage,flyer and plasma temperature during Boron Potassium Nitrate(BPN) ignition of the EFI.It was found that the EEC could enhance EFI ignition in terms of energy utilization,ignition contact surface,and high-temperature sustainability of plasma:firstly,the EEC prolonged the late time discharge(LTD) phase of the electric explosion,making the energy of capacitor effectively utilized;secondly,the EEC could create a larger area of ignition contact surface;last of all,the EEC effect enhanced its hightemperature sustainability by sustaining continuous energy input to plasma.It also was found that the ignition voltage of BPN could be reduced by nearly 600 V under the condition of 0.4 μF capacitance.The research has successfully combined EEC with EFI,revealing the behavioral characteristics of EEC and demonstrating its effective enhancement of EFI ignition.It introduces a new approach to improving EFI output,which is conducive to low-energy ignition of EFI,and expected to take the ignition technology of EFI to a new level. 展开更多
关键词 Exploding foil initiator Explosion-electricity coupling PLASMA Ignition mechanism Boron potassium nitrate
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Experimental investigation for temperature and emissivity by flame emission spectrum in a cavity of rocket based combined cycle combustor chamber
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作者 Weiguang Cai Shu Zheng +4 位作者 Yan Wang Bing Liu Shaohua Zhu Li Zhao Qiang Lu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期114-122,共9页
Flame temperature and spectral emissivity were the important parameters characterizing the sufficient degree of fuel combustion and the particle radiative characteristics in the Rocket Based Combined Cycle(RBCC)combus... Flame temperature and spectral emissivity were the important parameters characterizing the sufficient degree of fuel combustion and the particle radiative characteristics in the Rocket Based Combined Cycle(RBCC)combustor.To investigate the combustion characteristics of the complex supersonic flame in the RBCC combustor,a new radiation thermometry combined with Levenberg-Marquardt(LM)algorithm and the least squares method was proposed to measure the temperature,emissivity and spectral radiative properties based on the flame emission spectrum.In-situ measurements of the flame temperature,emissivity and spectral radiative properties were carried out in the RBCC direct-connected test bench with laser-induced plasma combustion enhancement(LIPCE)and without LIPCE.The flame average temperatures at fuel global equivalence ratio(a)of 1.0b and 0.6 with LIPCE were 4.51%and 2.08%higher than those without LIPCE.The flame combustion oscillation of kerosene tended to be stable in the recirculation zone of cavity with the thermal and chemical effects of laser induced plasma.The differences of flame temperature at a=1.0b and 0.6 were 503 K and 523 K with LIPCE,which were 20.07%and42.64%lower than those without LIPCE.The flame emissivity with methane assisted ignition was 80.46%lower than that without methane assisted ignition,due to the carbon-hydrogen ratio of kerosene was higher than that of methane.The spectral emissivities at 600 nm with LIPCE were 1.25%,22.2%,and 4.22%lower than those without LIPCE at a=1.0a(with methane assisted ignition),1.0b(without methane assisted ignition)and 0.6.The effect of concentration in the emissivity was removed by normalization to analyze the flame radiative properties in the RBCC combustor chamber.The maximum differences of flame normalized emissivity were 50.91%without LIPCE and 27.53%with LIPCE.The flame radiative properties were stabilized under the thermal and chemical effects of laser induced plasma at a=0.6. 展开更多
关键词 Rocket-based combined-cycle Supersonic combustion Flame temperature measurement EMISSIVITY Laser induced plasma combustion enhancement
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Effect of substrate temperature and oxygen plasma treatment on the properties of magnetron-sputtered CdS for solar cell applications
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作者 Runxuan Zang Haolin Wang +9 位作者 Xiaoqi Peng Ke Li Yuehao Gu Yizhe Dong Zhihao Yan Zhiyuan Cai Huihui Gao Shuwei Sheng Rongfeng Tang Tao Chen 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期22-33,I0010,共13页
Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films h... Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films have emerged,among which magnetron sputtering(MS)is one of the most commonly used vacuum techniques.For this type of technique,the substrate temperature is one of the key deposition parameters that affects the interfacial properties between the target film and substrate,determining the specific growth habits of the films.Herein,the effect of substrate temperature on the microstructure and electrical properties of magnetron-sputtered CdS(MS-CdS)films was studied and applied for the first time in hydrothermally deposited antimony selenosulfide(Sb_(2)(S,Se)_(3))solar cells.Adjusting the substrate temperature not only results in the design of the flat and dense film with enhanced crystallinity but also leads to the formation of an energy level arrangement with a Sb_(2)(S,Se)_(3)layer that is more favorable for electron transfer.In addition,we developed an oxygen plasma treatment for CdS,reducing the parasitic absorption of the device and resulting in an increase in the short-circuit current density of the solar cell.This study demonstrates the feasibility of MS-CdS in the fabrication of hydrothermal Sb_(2)(S,Se)_(3)solar cells and provides interface optimization strategies to improve device performance. 展开更多
关键词 magnetron sputtering CDS substrate heating plasma treatment Sb_(2)(S Se)_(3) thin film solar cell
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Unconditionally stable Crank-Nicolson algorithm with enhanced absorption for rotationally symmetric multi-scale problems in anisotropic magnetized plasma
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作者 WEN Yi WANG Junxiang XU Hongbing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期65-73,共9页
Large calculation error can be formed by directly employing the conventional Yee’s grid to curve surfaces.In order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is ... Large calculation error can be formed by directly employing the conventional Yee’s grid to curve surfaces.In order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is proposed for rotationally symmetric multi-scale problems in anisotropic magnetized plasma.Within the CNDG algorithm,an alternative scheme for the simulation of anisotropic plasma is proposed in body-of-revolution domains.Convolutional perfectly matched layer(CPML)formulation is proposed to efficiently solve the open region problems.Numerical example is carried out for the illustration of effectiveness including the efficiency,resources,and absorption.Through the results,it can be concluded that the proposed scheme shows considerable performance during the simulation. 展开更多
关键词 anisotropic magnetized plasma body-of-revolution(BOR) Crank-Nicolson Douglas-Gunn(CNDG) finite-difference time-domain(FDTD) perfectly matched layer(PML) rotationally symmetric multi-scale problems
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DC-Plasma-Jet表面冶金技术研究 被引量:18
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作者 李惠琪 李惠东 +3 位作者 李敏 孙玉宗 裴中爱 陈蕴博 《材料导报》 EI CAS CSCD 2004年第F10期194-197,共4页
分析了DC—Plasma—Jet直流放电压缩电孤等离子束表面冶金的技术内涵,研制了DC—Plasma—Jet表面冶金设备,对DC—Plasma—Jet表面冶金和目前的等离子堆焊技术进行了比较。DC—Plasma—Jet表面冶金是一种快速非平衡冶金反应过程,类似... 分析了DC—Plasma—Jet直流放电压缩电孤等离子束表面冶金的技术内涵,研制了DC—Plasma—Jet表面冶金设备,对DC—Plasma—Jet表面冶金和目前的等离子堆焊技术进行了比较。DC—Plasma—Jet表面冶金是一种快速非平衡冶金反应过程,类似粉末冶金,原则上可不受组成物的相溶性、熔点、密度等性质的限制,因此不需要预制合金雾化粉,可利用任意粉末的任意配比,获得通常冶金方法不能得到的组织与物相。DC—Plasma—Jet表面冶金方法效率高、操作简便、成本低、应用前景广阔。 展开更多
关键词 冶金技术 Plasma 表面冶金 JET 技术内涵 等离子束 直流放电 冶金设备 堆焊技术 反应过程 粉末冶金 前景广阔 DC 相溶性 组成物 成本低 雾化
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超细层状材料A_2La_2Ti_3O_(10)(A=Na,K)的低温合成及表征 被引量:5
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作者 张莉莉 刘冠鹏 +3 位作者 张维光 陆路德 杨绪杰 汪信 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第7期1093-1097,共5页
s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalli... s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalline phase of A2La2Ti3O10 can be obtained by thermal decomposition of citrate complex precursors at a relatively low temperature of 800 ℃ (600 ℃ for A=Na), about 300 ℃(500 ℃ for A=Na) lower than that of conventional solid state reaction process. The properties of the citrate precursors and the calcined powders were characterized by Infrared spectroscopy (IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal-gravimetric-differential thermal analysis (TG-DTA), inductively coupled plasma (ICP) and Brunauer-Emmett-Teller (BET) techniques. Results show that the average size of A2La2Ti3O10 powders obtained by citric acid sol-gel route was reduced to 200 nm×250 nm and the specific surface area was up to 19 m2·g-1. At the same time, the product was with more regular morphological characteristics. The synthesis process and the formation of A2La2Ti3O10 were also discussed. The obtained A2La2Ti3O10 was found to be transformed from A2La2Ti3O9.5 during the formation process. 展开更多
关键词 层状材料 低温合成 SOL-GEL La(NO3)3 Infrared analysis complex surface process 超细 表征 ACID plasma with the and phase solid The was SHOW area time MORE for can to be
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固相萃取高效液相色谱法测定人血浆中的巴洛沙星 被引量:5
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作者 邓金 肖正华 +2 位作者 张惠静 张梦军 汤建林 《色谱》 CAS CSCD 北大核心 2007年第6期942-943,共2页
建立了测定人血浆中巴洛沙星含量的固相萃取高效液相色谱紫外检测方法。采用pH4.5的磷酸盐缓冲液并经Waters Oasis HLB固相萃取小柱对血浆样品进行预处理。以环丙沙星作内标,以十二烷基磺酸钠溶液(取560mL水加入3.2g十二烷基磺酸钠... 建立了测定人血浆中巴洛沙星含量的固相萃取高效液相色谱紫外检测方法。采用pH4.5的磷酸盐缓冲液并经Waters Oasis HLB固相萃取小柱对血浆样品进行预处理。以环丙沙星作内标,以十二烷基磺酸钠溶液(取560mL水加入3.2g十二烷基磺酸钠)-乙腈(体积比为56:44,用磷酸调pH至3.0)为流动相,在Diamonsil C18色谱柱(150mm×4.6mm,5μm)上进行分离。方法的线性范围为25~3200μg/L,线性关系良好(r=0.9996);巴洛沙星的检出限(S/N≥3)为5μg/L;方法的准确度为100.3%-103.8%;平均提取回收率为57.5%~77.0%,相对标准偏差小于5.1%。方法准确、灵敏,可满足血药浓度监测和药代动力学参数测试的需求。 展开更多
关键词 固相萃取(SPE) 高效液相色谱法(HPLC) 巴洛沙星(balofloxacin) 血浆(plasma)
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GC-MS测定家犬血浆中银杏内酯A、B的含量 被引量:6
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作者 黄沛力 秦亚萍 +1 位作者 冯高谦 张磊 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期24-25,共2页
  银杏叶制剂作为治疗和预防动脉粥样硬化的有效药物,越来越为人们关注.银杏叶成分复杂,其中银杏黄酮具有扩张血管,降血脂,改善微循环的作用;银杏内酯是血小板活化因子强拮抗剂,对免疫系统,中枢神经系统,缺血损伤有保护作用,并有抗休...   银杏叶制剂作为治疗和预防动脉粥样硬化的有效药物,越来越为人们关注.银杏叶成分复杂,其中银杏黄酮具有扩张血管,降血脂,改善微循环的作用;银杏内酯是血小板活化因子强拮抗剂,对免疫系统,中枢神经系统,缺血损伤有保护作用,并有抗休克、抗过敏及抗炎作用.由于银杏内酯含量较低,对其进行的药动力学研究较少,且多采用的是非特异性的生物测定方法.…… 展开更多
关键词 Gas chromatography - mass spectrometry GINKGOLIDES Plasma
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高效液相色谱-离子阱质谱法测定人血浆中的头孢拉定和青霉素G 被引量:7
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作者 李晓东 尹利辉 冯玉飞 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期8-11,共4页
  目前,β-内酰胺类抗生素在临床抗感染药物中占有十分突出的地位[1],但在近年来的药品不良反应报告中,抗生素类药物引起的不良反应也占据了很高的比例,其中有我国生活环境影响、感染性疾病多的客观因素,但病人用药盲目性大、医生用...   目前,β-内酰胺类抗生素在临床抗感染药物中占有十分突出的地位[1],但在近年来的药品不良反应报告中,抗生素类药物引起的不良反应也占据了很高的比例,其中有我国生活环境影响、感染性疾病多的客观因素,但病人用药盲目性大、医生用药随意性多的问题也普遍存在.…… 展开更多
关键词 HPLC - Ion trap mass spectrometry Penicillin G CEFRADINE Drug concentration in plasma
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液相色谱-串联质谱法测定人血浆中的维拉帕米 被引量:5
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作者 张宏武 冯小龙 +1 位作者 张彦玲 杨汉煜 《色谱》 CAS CSCD 北大核心 2007年第1期113-114,共2页
关键词 液相色谱-串联质谱法(LC—MS/MS) 维拉帕米(verapamil) 血药浓度(plasma concentration)
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Plasma-MIG复合电弧焊接特性分析 被引量:3
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作者 杨涛 许可望 +2 位作者 刘永贞 高洪明 吴林 《焊接学报》 EI CAS CSCD 北大核心 2013年第5期62-66,116,共5页
采用Plasma-MIG复合电弧对Q235低碳钢进行堆焊试验,对焊接过程中复合电弧形态、电弧空间分布、焊缝成形及细晶原理进行了分析.结果表明,Plasma-MIG复合电弧焊接过程中,外层等离子电弧单独存在,内层MIG电弧在焊丝端部与外层等离子弧耦合... 采用Plasma-MIG复合电弧对Q235低碳钢进行堆焊试验,对焊接过程中复合电弧形态、电弧空间分布、焊缝成形及细晶原理进行了分析.结果表明,Plasma-MIG复合电弧焊接过程中,外层等离子电弧单独存在,内层MIG电弧在焊丝端部与外层等离子弧耦合.复合电弧空间温度分布均匀,高温停留时间短,冷却速度快.Plasma-MIG复合电弧在大的等离子电流下,促进填充金属润湿铺展,焊缝熔宽大,成形美观.相同热输入量条件下,等离子电流增大能够促进晶粒自发形核,原奥氏体晶粒及焊缝组织得到细化. 展开更多
关键词 Plasma—MIG复合电弧 电弧形态 空间温度分布 细化晶粒
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增量型PID恒流恒压控制的Plasma-MIG复合电弧焊接 被引量:3
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作者 杨涛 张生虎 +3 位作者 高洪明 吴林 许可望 刘永贞 《焊接学报》 EI CAS CSCD 北大核心 2013年第3期81-84,88,共5页
Plasma-MIG复合电弧焊接对电源的外特性输出及焊接过程控制有着很高的要求,以VC++软件开发工具为平台,推导了适合于Plasma-MIG复合电弧焊接的增量型PID控制算法,实现了对复合电弧焊接过程控制及电源外特性的要求.结果表明,增量型PID恒... Plasma-MIG复合电弧焊接对电源的外特性输出及焊接过程控制有着很高的要求,以VC++软件开发工具为平台,推导了适合于Plasma-MIG复合电弧焊接的增量型PID控制算法,实现了对复合电弧焊接过程控制及电源外特性的要求.结果表明,增量型PID恒流恒压控制能够满足Plasma-MIG对电源外特性的输出要求.Plasma电弧和MIG电弧并不是相互独立的,两者以共享的电磁空间、导电气氛和焊丝为媒介建立起耦合关系.Plasma-MIG复合电弧焊接过程中,增量型PID控制下的Plasma电弧能够自发的调节自身电参数,来稳定电弧空间的电流密度,使得焊接过程中无飞溅.采用控制后,Plasma-MIG复合电弧焊焊接过程焊缝铺展好,焊接过程稳定,焊缝成形好. 展开更多
关键词 Plasma—MIG复合电弧 增量型PID 焊接过程控制 外特性
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封闭酸溶-ICP-MS分析超细地质样品的条件优化 被引量:6
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作者 何红蓼 孙德忠 《质谱学报》 EI CAS CSCD 2005年第z1期23-24,72,共3页
Using ultra-fine sample for determination 42 elements by pressurized acid digestion -ICP-MS, the mass of test portion can be reduced to 2 mg yet maintain the representation. And acid used for digestion could be reduce... Using ultra-fine sample for determination 42 elements by pressurized acid digestion -ICP-MS, the mass of test portion can be reduced to 2 mg yet maintain the representation. And acid used for digestion could be reduced to less than 0.5 mL, reaction time also largely reduced. 展开更多
关键词 inductively plasma mass SPECTROMETRY (ICP-MS) ultra-fine sample pressurized acid DIGESTION
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