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Effect of matrix thermal properties on laser-induced plasma
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作者 Yuheng Shan An Li +4 位作者 Xinyu Zhang Wen Yi Ying Zhang Xiaodong Liu Ruibin Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期331-336,共6页
The matrix thermal properties have an important impact on laser-induced plasma,as the thermal effect dominates the interaction between ns-pulsed laser and matter,especially in metals.We used a series of pure metals an... The matrix thermal properties have an important impact on laser-induced plasma,as the thermal effect dominates the interaction between ns-pulsed laser and matter,especially in metals.We used a series of pure metals and aluminum alloys to measure plasma temperature and electron density through laser-induced breakdown spectroscopy,in order to investigate the effect of matrix thermal properties on laser-induced plasma.In pure metals,a significant negative linear correlation was observed between the matrix thermal storage coefficient and plasma temperature,while a weak correlation was observed with electron density.The results indicate that metals with low thermal conductivity or specific heat capacity require less laser energy for thermal diffusion or melting and evaporation,resulting in higher ablation rates and higher plasma temperatures.However,considering ionization energy,thermal effects may be a secondary factor affecting electron density.The experiment of aluminum alloy further confirms the influence of thermal conductivity on plasma temperature and its mechanism explanation. 展开更多
关键词 laser-induced plasma thermal properties matrix effect thermal storage coefficient plasma temperature
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A data selection method for matrix effects and uncertainty reduction for laser-induced breakdown spectroscopy 被引量:1
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作者 龙杰 宋惟然 +1 位作者 侯宗余 王哲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第7期82-89,共8页
Severe matrix effects and high signal uncertainty are two key bottlenecks for the quantitative performance and wide applications of laser-induced breakdown spectroscopy(LIBS).Based on the understanding that the superp... Severe matrix effects and high signal uncertainty are two key bottlenecks for the quantitative performance and wide applications of laser-induced breakdown spectroscopy(LIBS).Based on the understanding that the superposition of both matrix effects and signal uncertainty directly affects plasma parameters and further influences spectral intensity and LIBS quantification performance,a data selection method based on plasma temperature matching(DSPTM)was proposed to reduce both matrix effects and signal uncertainty.By selecting spectra with smaller plasma temperature differences for all samples,the proposed method was able to build up the quantification model to rely more on spectra with smaller matrix effects and signal uncertainty,therefore improving final quantification performance.When applied to quantitative analysis of the zinc content in brass alloys,it was found that both accuracy and precision were improved using either a univariate model or multiple linear regression(MLR).More specifically,for the univariate model,the root-mean-square error of prediction(RMSEP),the determination coefficients(R^(2))and relative standard derivation(RSD)were improved from 3.30%,0.864 and 18.8%to 1.06%,0.986 and 13.5%,respectively;while for MLR,RMSEP,R^(2)and RSD were improved from 3.22%,0.871 and 26.2%to 1.07%,0.986 and 17.4%,respectively.These results prove that DSPTM can be used as an effective method to reduce matrix effects and improve repeatability by selecting reliable data. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) quantification UNCERTAINTY univariate/multivariate analysis matrix effects temperature matching
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Matrix effect suppressing in the element analysis of soils by laser-induced breakdown spectroscopy with acoustic correction
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作者 何智权 刘莉 +6 位作者 郝中骐 徐智帅 王奇 卢颖 赵梓屹 史久林 何兴道 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第12期97-104,共8页
Laser-induced breakdown spectroscopy(LIBS)has been used for soil analysis,but its measurement accuracy is often influenced by matrix effects of different kinds of soils.In this work,a method for matrix effect suppress... Laser-induced breakdown spectroscopy(LIBS)has been used for soil analysis,but its measurement accuracy is often influenced by matrix effects of different kinds of soils.In this work,a method for matrix effect suppressing was developed using laser-induced plasma acoustic signals to correct the original spectrum,thereby improving the analysis accuracy of the soil elements.A good linear relationship was investigated firstly between the original spectral intensity and the acoustic signals.The relative standard deviations(RSDs)of Mg,Ca,Sr,and Ba elements were then calculated for both the original spectrum and the spectrum with the acoustic correction,and the RSDs were significantly reduced with the acoustic correction.Finally,calibration curves of MgⅠ285.213 nm,CaⅠ422.673 nm,SrⅠ460.733 nm and BaⅡ455.403 nm were established to assess the analytical performance of the proposed acoustic correction method.The values of the determination coefficient(R~2)of the calibration curves for Mg,Ca,Sr,and Ba elements,corrected by the acoustic amplitude,are improved from 0.9845,0.9588,0.6165,and 0.6490 to 0.9876,0.9677,0.8768,and 0.8209,respectively.The values of R~2 of the calibration curves corrected by the acoustic energy are further improved to 0.9917,0.9827,0.8835,and 0.8694,respectively.These results suggest that the matrix effect of LIBS on soils can be clearly improved by using acoustic correction,and acoustic energy correction works more efficiently than acoustic amplitude correction.This work provides a simple and efficient method for correcting matrix effects in the element analysis of soils by acoustic signals. 展开更多
关键词 laser-induced breakdown spectroscopy acoustic correction matrix effect calibration curve relative standard deviation
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Flatness Control Based on Dynamic Effective Matrix for Cold Strip Mills 被引量:24
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作者 LIU Hongmin HE Haitao +1 位作者 SHAN Xiuying JIANG Guangbiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第2期287-296,共10页
Steel strips are the main of steel products and flatness is an important quality indicator of steel strips. Flatness control is the key and highly difficult technique of strip mills. The bottle-neck restricting the im... Steel strips are the main of steel products and flatness is an important quality indicator of steel strips. Flatness control is the key and highly difficult technique of strip mills. The bottle-neck restricting the improvement of flatness control techniques is that the research on flatness theories and control mathematic models is not in accordance with the requirement of technique developments. To build a simple, rapid and accurate explicit formulation control model has become an urgent need for the development of flatness control technique. This paper puts forward the conception of dynamic effective matrix based on the effective matrix method for flatness control proposed by the authors under the consideration of the influence of the change of parameters in roiling processes on the effective matrix, and the concept is validated by industrial productions. Three methods of the effective matrix generation are induced: the calculation method based on the flatness prediction model; the calculation method based on the data excavation in rolling processes and the direct calculation method based on the network model. A fuzzy neural network effective matrix model is built based on the clusters, and then the network structure is optimized and the high-speed-calculation problem of the dynamic effective matrix is solved. The flatness control scheme for cold strip mills is proposed based on the dynamic effective matrix. On stand 5 of the 1 220 mm five-stand 4-high cold strip tandem mill, the industrial experiment with the control methods of tilting roll and bending roll is done by the control scheme of the static effective matrix and the dynamic effective matrix, respectively. The experiment result proves that the control effect of the dynamic effective matrix is much better than that of the static effective matrix. This paper proposes a new idea and method for the dynamic flatness control in the rolling processes of cold strip mills and develops the theory and model of the flatness control effective matrix method. 展开更多
关键词 cold strip mill flatness control dynamic effective matrix CLUSTER fuzzy neural network
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Thermal resistance matrix representation of thermal effects and thermal design of microwave power HBTs with two-dimensional array layout 被引量:2
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作者 Rui Chen Dong-Yue Jin +5 位作者 Wan-Rong Zhang Li-Fan Wang Bin Guo Hu Chen Ling-Han Yin Xiao-Xue Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第9期373-380,共8页
Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resist... Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resistance to describe the self-heating and thermal coupling effects, respectively.For HBT cells along the emitter length direction, the thermal coupling resistance is far smaller than the self-heating thermal resistance, and the peak junction temperature is mainly determined by the self-heating thermal resistance.However, the thermal coupling resistance is in the same order with the self-heating thermal resistance for HBT cells along the emitter width direction.Furthermore, the dependence of the thermal resistance matrix on cell spacing along the emitter length direction and cell spacing along the emitter width direction is also investigated, respectively.It is shown that the moderate increase of cell spacings along the emitter length direction and the emitter width direction could effectively lower the self-heating thermal resistance and thermal coupling resistance,and hence the peak junction temperature is decreased, which sheds light on adopting a two-dimensional non-uniform cell spacing layout to improve the uneven temperature distribution.By taking a 2 × 6 HBTs array for example, a twodimensional non-uniform cell spacing layout is designed, which can effectively lower the peak junction temperature and reduce the non-uniformity of the dissipated power.For the HBTs array with optimized layout, the high power-handling capability and thermal dissipation capability are kept when the bias voltage increases. 展开更多
关键词 HETEROJUNCTION BIPOLAR transistors(HBTs) array THERMAL effects THERMAL resistance matrix THERMAL design
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The effect of the fibre orientation of electrospun scaffolds on the matrix production of rabbit annulus fibrosus-derived stem cells 被引量:16
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作者 Chen Liu Caihong Zhu +4 位作者 Jun Li Pinghui Zhou Min Chen Huilin Yang Bin Li 《Bone Research》 SCIE CAS CSCD 2015年第2期112-120,共9页
Annulus fibrosus (AF) tissue engineering has recently received increasing attention as a treatment for intervertebral disc 0VD) degeneration; however, such engineering remains challenging because of the remarkable ... Annulus fibrosus (AF) tissue engineering has recently received increasing attention as a treatment for intervertebral disc 0VD) degeneration; however, such engineering remains challenging because of the remarkable complexity of AF tissue. In order to engineer a functional AF replacement, the fabrication of cell-scaffold constructs that mimic the cellular, biochemical and structural features of native AF tissue is critical. In this study, we fabricated aligned fibroua polyurethane scaffolds using an electrospinning technique and used them for culturing AF-derived-stem/progenitor cells (AFSCs). Random fibrous scaffolds, also prepared via electrospinningy were used as a control. We compared the morphology, proliferation, gene expression and matrix production of AFSCs on aligned scaffolds and random scaffolds. There was no apparent difference in the attachment or proliferation of cells cultured on aligned scaffolds and random scaffolds. However, compared to cells on random scaffolds, the AFSCs on aligned scaffolds were more elongated and better aligned, and they exhibited higher gene expression and matrix production of coUagen-I and aggrecan. The gene expression and protein production of coUagen-II did not appear to differ between the two groups. Together, these findings indicate that aligned fibrous scaffolds may provide a favourable microenvironment for the differentiation of AFSCs into cells similar to outer AF cells, which predominantly produce collagen-I matrix. 展开更多
关键词 The effect of the fibre orientation of electrospun scaffolds on the matrix production of rabbit annulus fibrosus-derived stem cells FIGURE STEM
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Elimination of matrix effects during analysis of perfluorinated acids in solid samples by liquid chromatography tandem mass spectrometry 被引量:2
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作者 李飞 赵志领 +2 位作者 沈春花 曾庆玲 刘淑坡 《Journal of Central South University》 SCIE EI CAS 2012年第10期2886-2894,共9页
Matrix effects can significantly hamper the accuracy and precision of the analysis results of perfluorinated acids (PFAs) in environmental solid samples. Several methods, such as standard addition, isotopically labe... Matrix effects can significantly hamper the accuracy and precision of the analysis results of perfluorinated acids (PFAs) in environmental solid samples. Several methods, such as standard addition, isotopically labeled internal standards, clean-up of SPE (solid phase extraction) eluents by dispersive graphitized carbon sorbent and substitution of eletrospray ionization (ESI) source by atmosphere pressure photoionization (APPI) source, were demonstrated for elimination of matrix effects in quantitative analysis of PFAs in solid samples. The resuRs indicate that matrix effects can be effectively eliminated by standard addition, but instrumental analysis time will be multiplied. Isotopically labeled internal standards can effectively negate matrix effects of PFAs with the same perfluorocarbon chain length, but is not valid for the other analytes. Although APPI can eliminate matrix effects for all analytes, it is only suitable for analysis of high pollution levels samples. Clean-up of SPE eluents by dispersive graphitized carbon sorbent not only effectively negate the impact of matrix effect, but also avoid frequent clean of the ESI in order to maintain instrumental sensitivity. Therefore, the best method for elimination of matrix effects is the usage of dispersive graphitized carbon sorbent for clean-up of SPE elution. 展开更多
关键词 matrix effects perfluorinated acids solid samples hydrophobic organic contaminants
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Effect of parameter setting and spectral normalization approach on study of matrix effect by laser induced breakdown spectroscopy of Ag–Zn binary composites 被引量:1
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作者 Harse SATTAR Liying SUN +3 位作者 Muhammad IMRAN Ran HAI Ding WU Hongbin DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期155-166,共12页
The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical perfo... The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical performance of three different normalization methods, namely normalization with background, internal normalization and three point smoothing techniques at different parameter settings is studied for quantification of Ag and Zn by Laser induced breakdown spectroscopy(LIBS).The LIBS spectra of five known concentration of silver zinc binary composites have been investigated at various laser irradiances(LIs). Calibration curves for both Ag(I) line(4d^(10)5s^2S_(1/2)→4d^(10)5p^2P_(1/2) at 338.28 nm) and Zn(I) line(4s5s^3S_1→4s4p^3P_2 at 481.053 nm) have been determined at LI of 5.86?×?10^(10)W cm^(-2). Slopes of these calibration curves provide the valuation of matrix effect in the Ag–Zn composites. With careful sample preparation and normalization after smoothing at optimum parameter setting(OPS), the minimization of sample matrix effect has been successfully achieved. A good linearity has been obtained in Ag and Zn calibration curve at OPS when normalized the whole area of spectrum after smoothing and the obtained coefficients of determination values were R^2?=?0.995 and 0.998 closer to 1. The results of matrix effect have been further verified by analysis of plasma parameters. Both plasma parameters showed no change with varying concentration at OPS. However, at high concentration of Ag, the observed significant changes in both plasma parameters at common parameter setting PS-1 and PS-2 were the gesture of matrix effect. In our case, the better analytical results were obtained at smoothing function with optimized parameter setting that indicates it is more efficient than normalization with background and internal normalization method. 展开更多
关键词 Ag–Zn COMPOSITES laser induced BREAKDOWN spectroscopy optimum parameter setting SELF-ABSORPTION matrix effect
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Matrix Effects of Fourteen Organophosphorus Pesticides Residues in Nine Kinds of Vegetable Matrices 被引量:1
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作者 Zhao Jianbo Li Deyu +2 位作者 Yu Qiaolan Du Fengshan Luo Junxia 《Plant Diseases and Pests》 CAS 2014年第1期39-44,共6页
The matrix effects of 14 organophosphorus pesticides in 9 kinds of vegetables matrices were preliminarily studied by gas chromatography/flame photomet- ric detection(FPD) in the paper. The matrix effects of 14 organ... The matrix effects of 14 organophosphorus pesticides in 9 kinds of vegetables matrices were preliminarily studied by gas chromatography/flame photomet- ric detection(FPD) in the paper. The matrix effects of 14 organophosphoms pesticides in 9 kinds of vegetable matrices at 0.05, 0.1 and 0.2 mg/L were compared, respectively. The results showed that matrix enhancement effect and matrix attenuation effect existed in all cases, while matrix effects did not have strong correlation with concentrations of pesticides, but were related to species of vegetables and structure and polarity of pesticides. 展开更多
关键词 Gas chromatography VEGETABLE Pesticide residue matrix effects CONCENTRATION
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Types and Correction Methods of Matrix Effect during Zircon LA-ICP-MS U-Pb Dating 被引量:1
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作者 WANG Jiasong PENG Lina +2 位作者 XU Yawen ZHANG Nan LI Guozhan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期2099-2100,共2页
Matrix effect primarily impacts the accuracy and precision of zircon LA-ICP-MS U-Pb data.This paper describes three types of matrix effect in zircon LA-ICPMS U-Pb dating,i.e.,the element matrix effect,high Ddpa or ura... Matrix effect primarily impacts the accuracy and precision of zircon LA-ICP-MS U-Pb data.This paper describes three types of matrix effect in zircon LA-ICPMS U-Pb dating,i.e.,the element matrix effect,high Ddpa or uranium matrix effect and alpha dose matrix effect,and illustrates the correction of these three effects.In addition,we point out the limitation and possible problems of the existing correction methods. 展开更多
关键词 PB Types and Correction Methods of matrix effect during Zircon LA-ICP-MS U-Pb Dating ICP MS
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Advance in Matrix Effect Study of LA-MC-ICPMS U-Pb Dating on U-Bearing Oxide Minerals 被引量:1
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作者 CUI Yurong TU Jiarun +3 位作者 GENG Jianzhen YE Lijuan ZHOU Hongying LI Huimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第4期1680-1681,共2页
Objective With the development of analytic technologies, in-situ dating on U-bearing oxide minerals (e.g., cassiterite, rutile and baddeleyite) has been widely used in geological chronological researches and has at... Objective With the development of analytic technologies, in-situ dating on U-bearing oxide minerals (e.g., cassiterite, rutile and baddeleyite) has been widely used in geological chronological researches and has attracted remarkable attention to explore evolution of the earth and obtain age information of various geological processes. Matrix effect related studies are especially important during in-situ U- Pb dating based on Laser Ablation Multiple Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC- ICPMS). However, to our knowledge, only few thorough and systematical matrix effect study of U-bearing oxide minerals has been reported. In this study, we systematically analyzed the matrix effect of U-bearing oxide minerals in order to take place the standards which are difficult to prepare with available standards. 展开更多
关键词 ICPMS ID Pb Advance in matrix effect Study of LA-MC-ICPMS U-Pb Dating on U-Bearing Oxide Minerals MC
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PARTICULATE SIZE EFFECTS IN THE PARTICLE-REINFORCED METAL-MATRIX COMPOSITES 被引量:13
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作者 魏悦广 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2001年第1期45-58,共14页
The influences of I,article size on the mechanical properties of the particulate metal matrix composite;are obviously displayed in the experimental observations. However, the phenomenon can not be predicted directly u... The influences of I,article size on the mechanical properties of the particulate metal matrix composite;are obviously displayed in the experimental observations. However, the phenomenon can not be predicted directly using the conventional elastic-plastic theory. It is because that no length scale parameters are involved in the conventional theory. In the present research, using the strain gradient plasticity theory, a systematic research of the particle size effect in the particulate metal matrix composite is carried out. The roles of many composite factors, such as: the particle size, the Young's modulus of the particle, the particle aspect ratio and volume fraction, as well as the plastic strain hardening exponent of the matrix material, are studied in detail. In order to obtain a general understanding for the composite behavior, two kinds of particle shapes, ellipsoid and cylinder, are considered to check the strength dependence of the smooth or non-smooth particle surface. Finally, the prediction results will be applied to the several experiments about the ceramic particle-reinforced metal-matrix composites. The material length scale parameter is predicted. 展开更多
关键词 size effect strain gradient plasticity the particle-reinforced metal-matrix composite
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Investigation of matrix effects in the MC-ICP-MS induced by Nb, W, and Cu: Isotopic case studies of iron and copper 被引量:5
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作者 SUN Jian ZHU Xiangkun +1 位作者 TANG Suohan CHEN Yuelong 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2013年第1期1-6,共6页
Some elements normally occur at trace levels while the majority of natural geological materials may be exceedingly enriched in some special cases, such as the Bayan Obo ore deposit where REE and Nb are extremely enric... Some elements normally occur at trace levels while the majority of natural geological materials may be exceedingly enriched in some special cases, such as the Bayan Obo ore deposit where REE and Nb are extremely enriched. These elements may not be removed completely during purification. Therefore, matrix effects will be caused during stable isotope ratio measurement in the MC-ICP-MS. Experiments have shown that the established methods of chromatographic separation of Cu, Fe, and Zn using AG MP-1 Anion Exchange Resin cannot make ef-fective separation of Nb, W, and Cu from Fe using 20 mL 6 M HCl. It is also observed that the elution curves of W and Cu overlap at working conditions and thus W is present in measurable amounts in some sample solutions. Matrix effects in the MC-ICP-MS induced by Nb, W, and Cu during Fe isotope ratio measurements and by W during Cu isotope ratio measurements were thus investigated by examining their changes in delta values between doped and undoped standards. The results show that the effects of the matrix elements Nb, W, or Cu on Fe isotope ratio measurements are minimal in the case of m(Nb)/m(Fe)<0.005, m(W)/m(Fe)<0.01, or m(Cu)/m(Fe)<0.6. This finding, combined with the extremely low levels of W and Cu, and the fact that nearly 90% of Nb can be removed during purification, demonstrates that the methods of chromatographic separation of Fe established before are suitable for Bayan Obo ore samples and that the methods can be simplified when Cu elution is unnecessary. The effects of the matrix element W on Cu isotope determinations are minimal in the case of m(W)/m(Cu)<0.7. Therefore, W exerts no significant effect on the measurements of Cu isotopes for the majority of natural geological materials. 展开更多
关键词 同位素比值 基体效应 CU NB 诱导 阴离子交换树脂 比率测量
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Neural network-based matrix effect correction in EDXRF analysis 被引量:4
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作者 TUO Xianguo CHENG Bo MU Keliang LI Zhe 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第5期278-281,共4页
In this paper we discuss neural network-based matrix effect correction in energy dispersive X-ray fluorescence (EDXRF) analysis,with detailed algorithm to classify the samples.The method can correct the matrix effect ... In this paper we discuss neural network-based matrix effect correction in energy dispersive X-ray fluorescence (EDXRF) analysis,with detailed algorithm to classify the samples.The method can correct the matrix effect effectively through classifying the samples automatically,and influence of X-ray absorption and enhancement by major elements of the samples is reduced.Experiments for the complex matrix effect correction in EDXRF analysis of samples in Pangang showed improved accuracy of the elemental analysis result. 展开更多
关键词 能量耗散X射线荧光分析 神经网络 聚类分析 基体效应 烧结矿物
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Preparation and Compressive Stress Effect of Polymer Matrix RE-Fe Giant Magnetostrictive Composite
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作者 Jiang Minhong Gu Zhengfei Cheng Gang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期723-723,共1页
Polymer matrix RE-Fe giant magnetostrictire composite (GMPC) was prepared using bonding and magnetic field forming technique, and magnetostriction of samples was measured for different compressive stress. The experi... Polymer matrix RE-Fe giant magnetostrictire composite (GMPC) was prepared using bonding and magnetic field forming technique, and magnetostriction of samples was measured for different compressive stress. The experimental results show thai there is certain compressive effect in GMPC. And the influence of compressive stress on magnetostriction of sample was investigated. It offers essential reference for application and device design of GMPC. 展开更多
关键词 MAGNETOSTRICTION polymer matrix COMPOSITES GMPC compressive stress effect rare earths
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A preliminary study of isopropyl alcohol matrix effect and correction in ICP-MS
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作者 Zhao Chu Hu Shan Gao +2 位作者 Sheng Hong Hu Yong Sheng Liu Hai Hong Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第10期1297-1300,共4页
Isopropyl alcohol matrix effect was found to be element specific by using the defined matrix effect factor in ICP-MS, which could not be corrected by using the conventional internal reference method. Unlike the conven... Isopropyl alcohol matrix effect was found to be element specific by using the defined matrix effect factor in ICP-MS, which could not be corrected by using the conventional internal reference method. Unlike the conventional internal reference method, the presented method allows for the analyte to behave differently from the internal reference under the influence of the matrix. 展开更多
关键词 ICP-MS Isopropyl alcohol matrix effect
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Effects of Activating Blood Circulation to Resolve Blood Stasis and Glucosamine Capsules Therapy on the Expression of Matrix Metalloproteinase in Post-traumatic Knee Osteoarthritis
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作者 Mingguang CHEN Shiqiang CHEN +5 位作者 Ning YANG Jin YANG Yingang LI Xiaoxia CAO Chunfeng CHANG Xuelan WU 《Medicinal Plant》 CAS 2019年第3期77-81,86,共6页
[Objectives] To observe the clinical effects of activating blood circulation to resolve blood stasis and glucosamine hydrochloride capsules therapy on post-traumatic knee osteoarthritis treatment,to measure the expres... [Objectives] To observe the clinical effects of activating blood circulation to resolve blood stasis and glucosamine hydrochloride capsules therapy on post-traumatic knee osteoarthritis treatment,to measure the expression of matrix metalloproteinase in post-traumatic knee osteoarthritis patients before and after treatment,and to explore its relevant molecular mechanisms. [Methods]A total of 60 patients with posttraumatic knee osteoarthritis in early stage in Affiliated Hospital of Shannxi University of Chinese Medicine from January 2015 to December2017 were selected and randomly divided into the control group( n = 30) and the observation group( n = 30). The control group was given oral administration of glucosamine hydrochloride capsules for 6 courses of the treatment. The observation group was using the activating blood circulation to resolve blood stasis therapy for 6 courses of treatment. The recovery of traumatic knee osteoarthritis and the symptom of traditional Chinese medicine( TCM) in 2 groups was compared before and after treatment. The symptoms and the quantitative assessment rating scale of knee osteoarthritis,the pain index of knee and the TCM symptom scores were recorded in both groups. And the synovial fluid and serum of patients were collected to detect the expression of matrix metalloproteinase. [Results]The symptoms and the quantitative assessment rating scale of knee osteoarthritis,the pain index of knee and TCM symptom scores of the 2 groups in the 1 st week,the 12 th week and the 24 th week after the treatment were significantly lower than those before the treatment,and the difference was statistically significant( P < 0. 05). Two therapeutic methods had certain therapeutic effects on the recovery from traumatic knee osteoarthritis,and could significantly improve the TCM syndrome. There were better therapeutic effects on oral decoction of traditional Chinese medicine than oral glycosaminoglycans hydrochloride capsules on treating traumatic knee osteogenesis( P < 0. 05). The expression level of MMP3 was decreased significantly in both groups( P <0. 001),while the expression level of MMP13 had no significant change in both groups( P >0. 05). The expression level of MMP1 was decreased significantly in the observation group( P < 0. 001),but there was no significant change in the control group after treatment( P >0. 05). [Conclusions]Two treatment methods have been effective in this clinical study. We found that the expression level of MMP3 was decreased significantly after treatment in 2 therapies,which can be clinically applied. 展开更多
关键词 Activating BLOOD CIRCULATION to RESOLVE BLOOD stasis GLUCOSAMINE hydrochloride Osteoarthritis Knee joint matrix metalloproteinases-1 matrix metalloproteinases-3 matrix metalloproteinases-13 Therapeutic effects
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Three-dimensional aspects of formulation excipients in drug discovery:a critical assessment on orphan excipients,matrix effects and drug interactions
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作者 Vijayabhaskar Veeravalli Hanumanth Srikanth Cheruvu +1 位作者 Pratima Srivastava Lakshmi Mohan Vamsi Madgula 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期522-531,共10页
Formulation/pharmaceutical excipients play a major role in formulating drug candidates,with the objectives of ease of administration,targeted delivery and complete availability.Many excipients used in pharmaceutical f... Formulation/pharmaceutical excipients play a major role in formulating drug candidates,with the objectives of ease of administration,targeted delivery and complete availability.Many excipients used in pharmaceutical formulations are orphanized in preclinical drug discovery.These orphan excipients could enhance formulatability of highly lipophilic compounds.Additionally,they are safe in preclinical species when used below the LD50 values.However,when the excipients are used in formulating compounds with diverse physico-chemical properties,they pose challenges by modulating study results through their bioanalytical matrix effects.Excipients invariably present in study samples and not in the calibration curve standards cause over-/under-estimation of exposures.Thus,the mechanism by which excipients cause matrix effects and strategies to nullify these effects needs to be revisited.Furthermore,formulation excipients cause drug interactions by moderating the pathways of drug metabolizing enzymes and drug transport proteins.Although it is not possible to get rid of excipient driven interactions,it is always advised to be aware of these interactions and apply the knowledge to draw meaningful conclusions from study results.In this review,we will comprehensively discuss a)orphan excipients that have wider applications in preclinical formulations,b)bioanalytical matrix effects and possible approaches to mitigating these effects,and c)excipient driven drug interactions and strategies to alleviate the impacts of drug interactions. 展开更多
关键词 Formulation excipients PRECLINICAL Drug discovery matrix effects Drug interactions BIOANALYSIS PHARMACOKINETICS Formulation development
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Effect of Sample Matrix on Radial and Axial Profiles of Ion Abundance in Inductively Coupled Plasma Mass Spectrometry
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作者 Clarisse Mariet Francine Carrot Mélanie Moskura 《American Journal of Analytical Chemistry》 2011年第7期739-751,共13页
In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis... In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis, other alternatives must be employed. Traditionally, the method of standard additions is used to correct the matrix effect but it is a time consuming method. Others methods involves separation techniques. Another way to overcome matrix interferences is to understand the mechanism involved and adjust plasma viewing conditions to reduce or eliminate the effect. In this study, the effect of various concomitant elements in ICP-MS was assessed by measuring the distribution of selected singly charged analyte ions (Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, In, Ba, La, Ce, Pb), doubly charged ions (La, Ce, Ba and Pb) and oxides ions (BaO) in the presence of concomitant elements spanning a mass range from 23 (Na) to 133 (Cs) u.m.a. and different ionization energies. Concomitant elements are alkali metals, alkaline earth metals and Si. Analyte ion suppression was observed while moving the ICP across and away from the sampling interface with or without a single concomitant element. Matrix effect measures were realised, firstly, to highlight the relation between the signal extinction of an analyte and the masse of the concomitant element, and secondly to highlight the relation between the removal of the analyte signal and the first ionization energy of the element of matrix. A dependence upon both the mass of the matrix element and the mass of the analyte was observed. The suppression seems increased with increasing matrix element mass and decreased with increasing analyte mass. The effect of the mass of the matrix element was the more significant of the two factors. If space-charge effects were found to be significant for matrix elements of much lower mass, it seems diffusion also played an active part for heavier matrix elements. Finally, some evidence was found for a shift in ion-atom equilibrium for dications and for energy demand regarding oxides. 展开更多
关键词 matrix effects Easily Ionized Elements Inductively Coupled Plasma Mass SPECTROMETRY Spatial PROFILING
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The neurotoxic effect of isoflurane on age-defined neurons generated from tertiary dentate matrix of dentate gyrus in mice
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作者 Xiao Xinli Yang Pengbo Liu Jianxin 《解剖学杂志》 CAS 2021年第S01期106-106,共1页
Recent animal studies showed that isoflurane exposure may lead to the disturbance of hippocampal neurogenesis and later cognitive impairment.However,much less is known about the effect of isoflurane exposure on the ne... Recent animal studies showed that isoflurane exposure may lead to the disturbance of hippocampal neurogenesis and later cognitive impairment.However,much less is known about the effect of isoflurane exposure on the neurons generated form tertiary dentate matrix of dentate gyrus,even though a great increase in granule cell population during the infantile period is principally derived from this site.To label the nascent cells from the tertiary dentate matrix of dentate gyrus,the mice were injected with bromodeoxyuridine(BrdU)on postnatal day 6(P6)and were exposed to isoflurane for 4 hat 1,8,21 day(s)and 42 day(s)after BrdU injection and the brains were collected 24 h later.The loss of different developmental stage nascent cells was assessed with BrdU,BrdU+DCX,BrdU+NeuN or BrdU+Prox-1 staining respectively.We found that the isoflurane significantly decreased the newly born(1-day old)cells and mature cells(42-day old),but not maturing cells(8-and 21-day old),suggesting isoflurane exposure exerts a neurotoxic effects on tertiary dentate matrix-originated nascent cells with an age defined pattern in mice. 展开更多
关键词 TERTIARY matrix effect
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