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A novel optical emission spectroscopy method for diagnostics of contribution of different ionization mechanisms and flux of ions in different valences in discharge channel of a Hall thruster

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Chinese Journal of Aeronautics 2024年第4期37卷 294-307页

作者： Yanfei WANG Ximing ZHU Renqiu ZOU Shilin YAN junwei jia Zhongxi NING Daren YU School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Aerospace Plasma Propulsion Ministry of Industry and Information TechnologyHarbin 150001China Beijing Orient Institute of Measurement and Test Beijing 100094China Beijing Aerospace Long March Aircraft Research Institute Beijing 100076China

The mass application of Hall thrusters poses the need for a diagnostic method of ionization mechanism in the discharge channel to boost the iteration and optimization of thruster *** work presents an Optical Emission Spectroscopy (OES) method for diagnostics of the contribution of different ionization mechanisms and the flux of ions in different valences in the discharge channel of a Hall *** emission spectra in the discharge channel are analyzed by jointly utilizing a collisional-radiative model,an ionization-excitation model,and a flux-conservation *** is found that the intensities of some spectral lines can be converted into the reaction rates of collision processes,e.g.,electron-induced excitation and ionization *** latter can further be used to determine the evolutions of particle fluxes by utilizing the conservation law of *** novel method is demonstrated on a kilo-watt Hall *** evolutions of several parameters are determined using this method along the discharge channel,including the ionization rates of different mechanisms,particle fluxes,particle densities,and particle *** novel method can be further developed by being jointly utilized with spectral imaging and tomography techniques,enabling diagnostics of multi-dimensional distributions of the above-mentioned parameters in the discharge channel and near-field plume.

关键词： Hall thruster Optical emission spectroscopy Ionization mechanism Particle flux Divalent ion

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Detection of Al, Mg, Ca, and Zn in copper slag by LIBS combined with calibration curve and PLSR methods

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Plasma Science and Technology 2024年第2期26卷 132-138页

作者：贾军伟刘志峰潘从元薛骅骎 School of Mechanical Engineering Hefei University of TechnologyHefei 230009People's Republic of China Hefei GStar Intelligent Control Technical Co.Ltd. Hefei 230088People's Republic of China Anhui Industrial Combustion Monitoring Technology and Equipment Engineering Laboratory Hefei 230088People's Republic of China

The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was utilized for the spectral analysis of copper slag samples at a distance of 2.5 m. The composition of copper slag was then analyzed using both the calibration curve(CC) method and the partial least squares regression(PLSR) analysis method based on the characteristic spectral intensity ratio. The performance of the two analysis methods was gauged through the determination coefficient(R^(2)), average relative error(ARE), root mean square error of calibration(RMSEC), and root mean square error of prediction(RMSEP). The results demonstrate that the PLSR method significantly improved both R^(2) for the calibration and test sets while reducing ARE, RMSEC, and RMSEP by 50% compared to the CC method. The results suggest that the combination of LIBS and PLSR is a viable approach for effectively detecting the elemental concentration in copper slag and holds potential for online detection of the elemental composition of high-temperature molten copper slag.

关键词： copper slag element remote LIBS PLSR

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响应面法优化超声辅助提取荆芥中维生素C工艺

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食品工业 2024年第4期45卷 13-16页

作者：陈姗姗贾俊伟黄河水利职业技术学院开封475004

采用响应面法对超声波辅助提取荆芥中维生素C的工艺进行研究。根据单因素试验结果,利用Central Composite Design原理进行响应面设计并进行优化。结果显示:当乙醇体积分数为70%,液料比为30:1(mL/g),超声温度为60℃,超声时间为30 min时,... 详细信息

采用响应面法对超声波辅助提取荆芥中维生素C的工艺进行研究。根据单因素试验结果,利用Central Composite Design原理进行响应面设计并进行优化。结果显示:当乙醇体积分数为70%,液料比为30:1(mL/g),超声温度为60℃,超声时间为30 min时,维生素C提取率24.39 mg/g,为最佳提取条件,而模型预测维生素C提取率为24.46mg/g,理论预测值与试验结果接近,说明该响应面模型有效可靠,为进一步开发利用香菜资源提供技术依据。

关键词：荆芥茎超声辅助提取维生素C 响应面法(RSM)

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Accuracy improvement of calibration-free laser-induced breakdown spectroscopy

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Plasma Science and Technology 2019年第3期21卷 6-15页

作者： Hongbo FU Zhibo NI Huadong WANG junwei jia Fengzhong DONG Anhui Provincial Key Laboratory of Photonics Devices and Materials Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Key Laboratory of Environmental Optics & Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences University of Science and Technology of China

Calibration-free laser-induced breakdown spectroscopy can overcome the matrix effect and the huge application prospects of in situ and on-line measurement, so it has been studied and applied to many analytical samples by numerous researchers since it was first proposed in ***, its accuracy is always lower than other analytical techniques and traditional quantitative analysis methods of laser-induced breakdown spectroscopy. The goal of this paper is to review the improvement of accuracy in the experimental setup and spectral analysis,especially after 2010, but not limited to it. The main contents include the accurate measurement of spectral intensity, the spatial and temporal window of local thermodynamic equilibrium and the accurate calculation of temperature and electron density. Due to the requirement of one or more standard samples, the combination of standard samples and CF-LIBS is discussed as a separate section. Finally, a simple conclusion is offered to relevant researchers who want to use CF-LIBS for quantitative analysis.

关键词： CF-LIBS quantitative analysis accuracy self-absorption local thermodynamic equilibrium

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转基因抗除草剂大豆ZH10-6转化体特异性定量检测体系的建立

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上海农业学报 2024年第3期40卷 1-7页

作者：白蓝贾军伟陈一帆章寅潘爱虎吴潇上海市农业科学院生物技术研究所上海201106 上海市农业遗传育种重点实验室农业农村部农作物生态环境安全检验测试中心(上海)上海201106 上海市农业生物安全评价与检测专业技术服务平台上海201106 上海市农业科学院畜牧兽医研究所上海201106 农业农村部农业转基因生物安全评价(环境)重点实验室上海201106

以新型转基因抗除草剂大豆ZH10-6外源插入片段的旁侧序列为靶标,建立了转化体特异性实时荧光PCR和单通道微滴式数字PCR精准定量检测体系,并邀请8家农业农村部检测中心对检测方法的准确性进行验证。结果表明:该转化体特异性实时荧光定量... 详细信息

以新型转基因抗除草剂大豆ZH10-6外源插入片段的旁侧序列为靶标,建立了转化体特异性实时荧光PCR和单通道微滴式数字PCR精准定量检测体系,并邀请8家农业农村部检测中心对检测方法的准确性进行验证。结果表明:该转化体特异性实时荧光定量检测方法具有良好的特异性、重复性及广泛的适用性,定量极限达到50 copies∕μL,检测极限达到5 copies∕μL。该检测方法有望作为检测标准用于转基因抗除草剂大豆ZH10-6的定量检测,为该大豆品系的商业化应用及转基因标识等监管提供技术支撑。

关键词：抗除草剂大豆ZH10-6 转化体特异性定量检测实时荧光PCR 微滴式数字PCR

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双层片剂的研究进展

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中国医药工业杂志 2024年第4期55卷 494-500页

作者：王楠时晓燕潘增玉贾俊伟冯中无山东中医药大学药学院山东济南250355 鲁南制药集团股份有限公司山东省药物国际化工程实验室山东临沂273400 鲁南贝特制药有限公司药物新制剂研发山东省工程研究中心山东临沂276006

双层片剂是一种广受关注的新型制剂,具有双层结构,可通过联合用药或调整释药速率来增强药效、减轻药物不良反应、提高患者依从性。该综述总结了近年来双层片剂的研究进展,汇总了双层片剂的特点、制备方法和分类情况,并结合案例介绍了双... 详细信息

双层片剂是一种广受关注的新型制剂,具有双层结构,可通过联合用药或调整释药速率来增强药效、减轻药物不良反应、提高患者依从性。该综述总结了近年来双层片剂的研究进展,汇总了双层片剂的特点、制备方法和分类情况,并结合案例介绍了双层片剂的临床应用情况,以期为双层片剂的研究与开发提供参考。

关键词：双层片速释层缓释层药效固体制剂

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Calibration curve and support vector regression methods applied for quantification of cement raw meal using laser-induced breakdown spectroscopy

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Plasma Science and Technology 2019年第3期21卷 23-30页

作者： junwei jia Hongbo FU Zongyu HOU Huadong WANG Zhibo NI Fengzhong DONG Anhui Provincial Key Laboratory of Photonic Devices and Materials Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences University of Science and Technology of China State Key Lab of Power Systems Department of Thermal Engineering Tsinghua-BP Clean Energy Center Tsinghua University

Laser-induced breakdown spectroscopy(LIBS) is a qualitative and quantitative analytical technique with great potential in the cement industrial analysis. Calibration curve(CC) and support vector regression(SVR) methods coupled with LIBS technology were applied for the quantification of three types of cement raw meal samples to compare their analytical concentration range and the ability to reduce matrix effects, respectively. To reduce the effects of fluctuations of the pulse-to-pulse, the unstable ablation and improve the reproducibility, all of the analysis line intensities were normalized on a per-detector basis. The prediction results of the elements of interest in the three types of samples, Ca, Si, Fe, Al, Mg, Na, K and Ti, were compared with the results of the wet chemical analysis. The average relative error(ARE),relative standard deviation(RSD) and root mean squared error of prediction(RMSEP) were employed to investigate and evaluate the prediction accuracy and stability of the two prediction methods. The maximum average ARE of the CC and SVR methods is 34.62% instead of 6.13%,RSD is 40.89% instead of 7.60% and RMSEP is 1.34% instead of 0.43%. The results show that SVR method can accurately analyze samples within a wider concentration range and reduce the matrix effects, and LIBS coupled with it for a rapid, stable and accurate quantification of different types of cement raw meal samples is promising.

关键词： cement raw meal calibration curves SVR LIBS

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一种等离子体溯源测量装置设计及性能测试

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航天器环境工程 2024年第2期41卷 181-189页

作者：李耀贾军伟王青青武宇婧常猛董学江郝剑昆郎昊李绍飞张韧北京东方计量测试研究所北京100086

文章设计了一套等离子体溯源测量装置为验证感应耦合等离子体(ICP)源作为校准源的性能,找出满足朗缪尔探针溯源校准的最佳等离子体测试条件,提升测试准确性,采用控制变量法对不同工况下ICP源等离子体电子密度和电子温度的稳定性和均匀性... 详细信息

文章设计了一套等离子体溯源测量装置为验证感应耦合等离子体(ICP)源作为校准源的性能,找出满足朗缪尔探针溯源校准的最佳等离子体测试条件,提升测试准确性,采用控制变量法对不同工况下ICP源等离子体电子密度和电子温度的稳定性和均匀性,以及电子密度的重复性进行测试。结果表明:在放电开始5~20 min内,等离子体电子密度和电子温度的稳定性分别优于99.4%和98.9%;在探针伸入真空腔体内440~480 mm的范围内,等离子体电子密度和电子温度的均匀性分别优于97.2%和93.6%;在等离子体源放电功率100~900 W范围时,等离子体电子密度的重复性优于86.6%,并且多数在92%以上。本研究可为后续等离子体诊断手段的优化提供参考。

关键词：等离子体源朗缪尔探针控制变量法结构设计电子密度电子温度

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噁拉戈利钠片的制备及体内外评价

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中国医药工业杂志 2024年第2期55卷 253-260页

作者：贾俊伟朱志祥李正照庞余江张丽萍冯中中国海洋大学山东青岛266003 鲁南制药集团股份有限公司山东省药物国际化工程实验室山东临沂273400

该研究制备了噁拉戈利钠自研片,并以溶出相似因子f_(2)为判断指标,优化了活性药物成分(API)粒径、干法制粒过筛筛网孔径以及片剂硬度等3个关键制剂工艺参数。结果显示,当API的粒径[d(0.9)]为250μm、干法制粒过筛筛网的孔径为1.4 mm、... 详细信息

该研究制备了噁拉戈利钠自研片,并以溶出相似因子f_(2)为判断指标,优化了活性药物成分(API)粒径、干法制粒过筛筛网孔径以及片剂硬度等3个关键制剂工艺参数。结果显示,当API的粒径[d(0.9)]为250μm、干法制粒过筛筛网的孔径为1.4 mm、片剂硬度为80 N时,自研片与参比制剂的体外释放行为一致。随后,该研究采用平行人工膜渗透分析(PAMPA)法中相关的渗透参数和在Beagle犬体内的药物动力学特征来研究自研片的生物等效性。结果表明,自研片和参比制剂的渗速率分别为8.6988和8.1616μg·mL^(-1)·min^(-1),膜渗透性分别为2.24×10^(-4)和2.10×10^(-4)cm/s,自研片的置信区间为100.82%~104.54%;两者的药动学参数均无统计学差异(P>0.05),自研片的相对生物利用度为(95.4±8.69)%,与参比制剂生物等效。

关键词：噁拉戈利钠工艺参数平行人工膜渗透分析生物等效性

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Comparison of Model Checking Tools

Comparison of Model Checking Tools

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2012 2nd International Conference on Advanced Materials and Computer Science(ICAMCS 2012)

作者： Wei Gong junwei jia School of Control and Mechanical Engineering Tianjin Institute of Urban Construction School of Computer and Information Engineering Tianjin Institute of Urban Construction

Model Checking is a method for verification. The model will be checked until the specification of it is proved or disproved. With the rising complexity of big models, there are non-checkable cases, in which cases the problem can be analyzed by some models, for example, bounded Model Checking means to analyze the model until a defined time or depth. The verification happens automatically. The programs for doing this are called Model Checking Tools or Model Checker. Model Checking are used in both software and hardware verification. It is an inherent part of hardware verification, whereas it is less used in the software verification.

关键词： Model checking Mocha Prism NuSMV

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