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法律法规要提供坚实保障——访国家质检总局法规司副司长刘兆彬
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作者 李滨 《中国质量技术监督》 2001年第12期20-20,共1页
作为行使着行政执法职能的国家质检总局,法规司可称得上是它的"心脏".法规司承担的一项重要任务是质量监督检验检疫方面的法律法规草案的起草,以及拟定有关规章,承办发布部门规章的工作,并管理着与质量监督检验检疫有关的技... 作为行使着行政执法职能的国家质检总局,法规司可称得上是它的"心脏".法规司承担的一项重要任务是质量监督检验检疫方面的法律法规草案的起草,以及拟定有关规章,承办发布部门规章的工作,并管理着与质量监督检验检疫有关的技术法规工作. 展开更多
关键词 中国 质量监督检验检疫 技术 标准经 产品质量 高检法 计量
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Simultaneous Determination of Baicalin, Berberine and Rhein by HPLC in Traditional Chinese Patent Medicine Sanhuang Tablets 被引量:5
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作者 李奕 高建平 许旭 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期110-114,共5页
Aim To establish a reversed phase liquid chromatographic method forsimultaneous determination of three main medicinal constituents, baicalin, berberine and rhein, inSanhuang tablets. Methods The separation was perform... Aim To establish a reversed phase liquid chromatographic method forsimultaneous determination of three main medicinal constituents, baicalin, berberine and rhein, inSanhuang tablets. Methods The separation was performed on a Kromasil C_(18) column with TEA-adjusted0.02 mol·L^(-1) H_3PO_4 (pH 6.78)-acetonitrile-methanol (40 : 9 : 7) as mobile phase at aflow-rate of 1.0 mL·min^(-1), with detection at 254 ran. Considering interaction between acidic andalkaline compounds, three standard markers were added respectively and the volume of samplesolution was doubled in recovery experiments. Results Three regression equations revealed excellentlinear relationship between the peak areas and concentrations and the correlation coefficients allsurpassed 0.999 8. The average recovery was 96.1% (RSD = 2.1%) baicalin, 98.5% (RSD = 2.4%) forberberine, and 101.5% (RSD =1.3%) for rhein. Conclusion The method developed can be used to controlthe quality of Sanhuang tablets comprehensively. 展开更多
关键词 sanhuang tablets BAICALIN RHEIN BERBERINE HPLC
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Optimization of Chromatographic Conditions for Detecting Ellagic Acid in Pomegranate Peels Using HPLC Method 被引量:3
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作者 夏小龙 彭蓉 +3 位作者 李树垠 李端阳 干霞 白琦 《Agricultural Science & Technology》 CAS 2012年第11期2400-2403,共4页
[Objective] This study aimed to optimize the chromatographic conditions for detecting ellagic acid in pomegranate peels using HPLC method. [Method] By using 0.2 mg/ml ellagic acid standard solution, on the basis of si... [Objective] This study aimed to optimize the chromatographic conditions for detecting ellagic acid in pomegranate peels using HPLC method. [Method] By using 0.2 mg/ml ellagic acid standard solution, on the basis of single-factor experiment and orthogonal experiment, chromatographic conditions (mobile phase ratio, flow rate, col- umn temperature) for detecting ellagic acid using HPLC were optimized. Based on the optimal chromatographic conditions, the ellagic acid content in experimental pomegranate peels was determined. [Resull] The optimal chromatographic conditions for detecting ellagic acid in pomegranate peels using HPLC method are: 1.2% phos- phoric acid:acetonitrile=85:15, column temperature of 35 ℃, and flow rate of 1.0 ml/min. The linear regression equation of ellagic acid is: y=2.9e+0.6x+4.4e+5 (FF=9 999). Ac- cording to the standard addition recovery test, the average recovery rate of ellagic acid is 98.20%, and RSD is 0.60%. Under above optimized chromatographic condi- tions, ellagic acid can be well separated from other interfering components in pomegranate peels, with shorter peak time and ideal effect, which is convenient for the detection in production practices. [Conclusion] This study laid the foundation for detecting ellagic acid in pomegranate peels using HPLC method. 展开更多
关键词 Pomegranate peel Etlagic acid DETECTION HPLC
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Determination of Candicidin/FR-008 and Related Components in Fermentation Broth by RP-HPLC
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作者 毛相朝 沈亚领 +2 位作者 魏东芝 陈实 邓子新 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期115-118,共4页
Aim A liquid chromatographic method for the determination ofcandicidin/FR-008 and related components in fermentation broth has been developed. Methods Therewere four major components in the candicidin/FR-008 complex, ... Aim A liquid chromatographic method for the determination ofcandicidin/FR-008 and related components in fermentation broth has been developed. Methods Therewere four major components in the candicidin/FR-008 complex, which were separated by HPLC under thefollowing conditions: SB-C8 column (4.6 mm x 250 mm, 5 μm) was used, the mobile phase consisted ofacetonitrileam-monium acteate (20 mmol·L^(-1) , pH 4.0) (40:60, V/V) , with a flow rate of 1 .0mL·min^(-1) , the UV detection wavelength was 380 nm, and the whole process was performed at 25℃ .Results The linearity was obtained in the range of 6.25 - 500 μg· mL^(-1) candicidin/FR-008 withthe regression equation of Y = 20 461 x + 30 748 and the correlation coefficient of 0.999 1. Theinstrument precision was 1.84% and the method precision was 3.8%. Conclusion This method isaccurate, rapid and simple; it can be used for determination of candicidin/FR-008 and relatedcomponents in fermentation broth. 展开更多
关键词 candicidin/FR-008 HPLC fermentation broth METABOLITES
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Quick valence analysis method of vanadium toward accurate toxicity assessment of vanadium-containing hazardous wastes 被引量:2
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作者 Hong-yi LI Xin-mian CHEN +3 位作者 Dan-qing LI Yun GUO Jiang DIAO Bing XIE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3602-3613,共12页
In order to develop a quick, efficient and sensitive valence analysis method of vanadium(Ⅴ), the highperformance liquid chromatography(HPLC) was utilized to separate and quantify EDTA-complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(... In order to develop a quick, efficient and sensitive valence analysis method of vanadium(Ⅴ), the highperformance liquid chromatography(HPLC) was utilized to separate and quantify EDTA-complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(Ⅴ) ions. The influence of EDTA, TBAOH, solution pH and organic modifier on retention behavior of V-EDTA complexes was investigated. Complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(Ⅴ) ions can be separated and quantified in 5 min, with detection limits of 0.04 mg/L Ⅴ(Ⅲ), 0.07 mg/L Ⅴ(Ⅳ), and 0.06 mg/L Ⅴ(Ⅴ), respecti vely. The established method is applied to analyzing the hazardous waste of V-Cr-bearing reducing slag and results demonstrate 49.94% of its Ⅴ element to be toxic Ⅴ(Ⅴ). This work opens a new avenue for quick and accurate toxicity assessment of hazardous wastes containing multivalent heavy metals. 展开更多
关键词 VANADIUM VALENCE HPLC-UV mass spectrometry EDTA
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Review of Shadow Detection and De-shadowing Methods in Remote Sensing 被引量:10
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作者 AmirReza SHAHTAHMASSEBI YANG Ning +2 位作者 WANG Ke Nathan MOORE SHEN Zhangquan 《Chinese Geographical Science》 SCIE CSCD 2013年第4期403-420,共18页
Shadow is one of the major problems in remotely sensed imagery which hampers the accuracy of information extraction and change detection.In these images,shadow is generally produced by different objects,namely,cloud,m... Shadow is one of the major problems in remotely sensed imagery which hampers the accuracy of information extraction and change detection.In these images,shadow is generally produced by different objects,namely,cloud,mountain and urban materials.The shadow correction process consists of two steps:detection and de-shadowing.This paper reviews a range of techniques for both steps,focusing on urban regions(urban shadows),mountainous areas(topographic shadow),cloud shadows and composite shadows.Several issues including the problems and the advantages of those algorithms are discussed.In recent years,thresholding and recovery techniques have become important for shadow detection and de-shadowing,respectively.Research on shadow correction is still an important topic,particularly for urban regions(in high spatial resolution data) and mountainous forest(in high and medium spatial resolution data).Moreover,new algorithms are needed for shadow correction,especially given the advent of new satellite images. 展开更多
关键词 SHADOW detection de-shadowing URBAN FOREST
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Ultrasonography in differentiation between chronic viral hepatitis and compensated early stage cirrhosis
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作者 Panagiotis Iliopoulos Marianna Vlychou +4 位作者 Chrisoula Karatza Spyros D Yarmenitis Maria Repanti Ioannis Tsamis Kostantinos Tepetes 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第13期2072-2079,共8页
AIM: To assess the value of gray scale (GS) and colour Doppler ultrasonography (CDU) in differentiating the progression of chronic viral hepatitis (CVH) and compensated liver cirrhosis (CIR). METHODS: Seventy-two pati... AIM: To assess the value of gray scale (GS) and colour Doppler ultrasonography (CDU) in differentiating the progression of chronic viral hepatitis (CVH) and compensated liver cirrhosis (CIR). METHODS: Seventy-two patients and 32 normal individuals who were used as controls were studied. Forty-four patients suffered from CVH and 28 from CIR. All patients were underwent to liver biopsy. Multiple qualitative and quantitative variables were studied in liver, portal vein (PV), hepatic artery (HA) and spleen with GS and CDU. On the basis of the obtained CDU data, several known indexes were calculated. In addition, alternative indices [PV diameter (D)/time average mean velocity (VTAM), HA/PV VTAM ratio] were calculated and studied. RESULTS: ROC analysis showed that PV congestion index, PV D/VTAM and HA/PV VTAM indices had the best sensitivity and specificity in discriminating CVH from CIR. Stepwise discriminant analysis showed that 88.9% of the originally grouped cases could be correctly classified by the three qualitative and four quantitative variables selected as statistically significant predictors. Among the CVH patients who underwent to biopsy, statistically significant changes were found in those at fibrosis stage 5 compared to fibrosis stages 1-4. CONCLUSION: Simple GS and CDU parameters discri-minate CVH from CIR. The alternative Doppler indexes can accurately differentiate chronic virus hepatitis from cirrhosis. These indexes can be used in monitoring chronic virus hepatitis and avoiding unnecessary biopsies. 展开更多
关键词 Liver cirrhosis Virus hepatitis Portal hypertension Doppler ultrasonography
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High-flow nasal oxygen availability for sedation decreases the use of general anesthesia during endoscopic retrograde cholangiopancreatography and endoscopic ultrasound 被引量:10
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作者 Roman Schumann Nikola S Natov +4 位作者 Klifford A Rocuts-Martinez Matthew D Finkelman Tom V Phan Sanjay R Hegde Robert M Knapp 《World Journal of Gastroenterology》 SCIE CAS 2016年第47期10398-10405,共8页
AIM To examine whether high-flow nasal oxygen(HFNO) availability influences the use of general anesthesia(GA) in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic ultrasound(EUS) ... AIM To examine whether high-flow nasal oxygen(HFNO) availability influences the use of general anesthesia(GA) in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic ultrasound(EUS) and associated outcomes.METHODS In this retrospective study, patients were stratified into 3 eras between October 1, 2013 and June 30, 2014 based on HFNO availability for deep sedation at the time of their endoscopy. During the first and last 3-mo eras(era 1 and 3), no HFNO was available, whereas it was an option during the second 3-mo era(era 2). The primary outcome was the percent utilization of GA vs deep sedation in each period. Secondary outcomes included oxygen saturation nadir during sedation between periods, as well as procedure duration, and anesthesia-only time between periods and for GA vs sedation cases respectively.RESULTS During the study period 238 ERCP or EUS cases were identified for analysis. Statistical testing was employed and a P < 0.050 was significant unless the Bonferroni correction for multiple comparisons was used. General anesthesia use was significantly lower in era 2 compared to era 1 with the same trend between era 2 and 3(P = 0.012 and 0.045 respectively). The oxygen saturation nadir during sedation was significantly higher in era 2 compared to era 3(P < 0.001) but not between eras 1 and 2(P = 0.028) or 1 and 3(P = 0.069). The procedure time within each era was significantly longer under GA compared to deep sedation(P ≤ 0.007) as was the anesthesia-only time(P ≤ 0.001).CONCLUSION High-flow nasal oxygen availability was associated with decreased GA utilization and improved oxygenation for ERCP and EUS during sedation. 展开更多
关键词 Endoscopic ultrasound Endoscopic retrograde cholangiopancreatography ENDOSCOPY SEDATION ANESTHESIA OXYGENATION High flow nasal oxygen
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Determination of Sulphonamide Antibiotics and Trimethoprim in Wastewater and Sludge Using Liquid Chromatography with Diode-Array Detection 被引量:1
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作者 Petra Zenatova Milada Vavrova Ludmila Mravcova Hana Lisa 《Journal of Environmental Science and Engineering(A)》 2012年第2期175-180,共6页
This paper investigates the occurrence of sulphonamide and diaminopyrimidine antibiotics in wastewater and sludge from wastewater treatment plants. In our experiment, they were isolated from wastewater using the solid... This paper investigates the occurrence of sulphonamide and diaminopyrimidine antibiotics in wastewater and sludge from wastewater treatment plants. In our experiment, they were isolated from wastewater using the solid phase extraction method. In the case of sludge, pressurized solvent extraction techniques were used followed by solid phase extraction. The solid phase extraction method was used for purification and concentration. Sulphonamide and diaminopyrimidine antibiotics were determined using high performance liquid chromatography with diode-array detection. The selected antibiotics were determined in real sludge samples collected from the wastewater treatment plant in Brno-Mod^ice and in real wastewater samples collected from the wastewater treatment plant located on the grounds of the University of Veterinary and Pharmaceutical Sciences in Brno, using the developed and optimized method. Analyses showed that real samples of wastewater contained sulphathiazole 11.82μg/L at the inflow (7.1 μg/L at the outflow), sulphapyridine 18.57 I.tg/L (12.2 μg/L), sulphamethazine 13.52 μg/L (8.44 μg/L), sulphamethoxazole 14.06 lag/L (9.34 Ixg/L) and trimethoprim 521.4 lag/L (422.29 μg/L). Here it is demonstrated that drugs are removed through the wastewater treatment procedure only partially. 展开更多
关键词 Drug residues ANTIBIOTICS SLUDGE WASTEWATER pressurized solvent extraction liquid chromatography.
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Indices of Sulfur-Supplying Capacities of Upland Soils in North China
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作者 LIN BAO ZHOU WEI LI SHUTIAN and WANG HONG (Institute of Soil and Fertilized, Chinese Academy of Agricultural Sciences, SO Baishiqiao Road, Beijing 100081, China) 《Pedosphere》 SCIE CAS CSCD 1999年第1期25-34,共10页
Fifteen upland soils collected from the major arable areas in North China were used to assess the availability of soil sulfur (S) to plants in a pot experiment. Soils were extracted with various reagents and the extra... Fifteen upland soils collected from the major arable areas in North China were used to assess the availability of soil sulfur (S) to plants in a pot experiment. Soils were extracted with various reagents and the extractable S was determined using turbidimetric method or inductively coupled plasma atomic emission spectrometry (ICP-AES), respectively. In addition, mineralizable organic S, organic S, N/S ratio, sulfur availability index (SAI) and available sulfur correction value (ASC) in soils were also determined. The S amount extracted by 1.5 g L-1 CaCl2 was nearly equivalent to that by 0.25 mol L-1 KCl (40 ℃), and both of them were slightly smaller than that by 0.01 mol L-1 Ca(H2PO4)2 solution, as measured by turbidimetric method or ICP-AES. The extractable S measured by turbidimetric method was consistently smaller than that by ICP-AES. All methods tested except that for organic S and N/S ratio produced satisfactory results in the regression analyses of the relationships between the amounts of S extracted and plant dry matter weight and S uptake in the pot experiment. In general, 0.01 mol L-1 Ca (H2PO4) 2-extracted S determined by ICP-AES or turbidimetric method and 0.25 mol L-1 KCl(40℃)-extracted S determined by ICP-AES appeared to be the best indicators for evaluation of soil available S. 展开更多
关键词 soil available sulfur testing methods upland soils
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Fault detection of large-scale process control system with higher-order statistical and interpretative structural model 被引量:1
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作者 耿志强 杨科 +1 位作者 韩永明 顾祥柏 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期146-153,共8页
Nonlinear characteristic fault detection and diagnosis method based on higher-order statistical(HOS) is an effective data-driven method, but the calculation costs much for a large-scale process control system. An HOS-... Nonlinear characteristic fault detection and diagnosis method based on higher-order statistical(HOS) is an effective data-driven method, but the calculation costs much for a large-scale process control system. An HOS-ISM fault diagnosis framework combining interpretative structural model(ISM) and HOS is proposed:(1) the adjacency matrix is determined by partial correlation coefficient;(2) the modified adjacency matrix is defined by directed graph with prior knowledge of process piping and instrument diagram;(3) interpretative structural for large-scale process control system is built by this ISM method; and(4) non-Gaussianity index, nonlinearity index, and total nonlinearity index are calculated dynamically based on interpretative structural to effectively eliminate uncertainty of the nonlinear characteristic diagnostic method with reasonable sampling period and data window. The proposed HOS-ISM fault diagnosis framework is verified by the Tennessee Eastman process and presents improvement for highly non-linear characteristic for selected fault cases. 展开更多
关键词 High order statistics Nonlinear characteristics diagnosis Interpretative structural model TE process
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Visual positioning of rectangular lead components based on Harris corners and Zernike moments 被引量:5
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作者 王祖进 黄筱调 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2586-2595,共10页
With the increasing necessities for reliable printed circuit board(PCB) product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component... With the increasing necessities for reliable printed circuit board(PCB) product, there has been a considerable demand for high speed and high precision vision positioning system. To locate a rectangular lead component with high accuracy and reliability, a new visual positioning method was introduced. Considering the limitations of Ghosal sub-pixel edge detection algorithm, an improved algorithm was proposed, in which Harris corner features were used to coarsely detect the edge points and Zernike moments were adopted to accurately detect the edge points. Besides, two formulas were developed to determine the edge intersections whose sub-pixel coordinates were calculated with bilinear interpolation and conjugate gradient method. The last experimental results show that the proposed method can detect the deflection and offset, and the detection errors are less than 0.04° and 0.02 pixels. 展开更多
关键词 visual positioning Harris corners Zernike moments edge detection sub-pixel image registration
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A Physics-Based Dual-Frequency Approach for Altimeter Wind Speed Retrieval
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作者 LI Shuiqing ZHOU Liangming +3 位作者 LI Zhanbin MIAO Qingsheng MOU Lin WANG Aifang 《Journal of Ocean University of China》 SCIE CAS 2014年第4期579-583,共5页
The altimeter normalized radar cross section(NRCS) has been used to retrieve the sea surface wind speed for decades, and more than a dozen of wind speed retrieval algorithms have been proposed. Despite the continuing ... The altimeter normalized radar cross section(NRCS) has been used to retrieve the sea surface wind speed for decades, and more than a dozen of wind speed retrieval algorithms have been proposed. Despite the continuing efforts to improve the wind speed measurements, a bias dependence on wave state persists in all wind algorithms. On the basis of recent evidence that short waves are essentially modulated by local winds and much less affected by wave state, we proposed a physics-based approach to retrieve the wind speed from the dual-frequency difference in terms of the mean square slope of short waves. A collocated dataset of coincident altimeter/buoy measurements were used to develop and validate the approach. Validation against buoy measurements indicates that the approach is almost unbiased and has an overall root mean square error of 1.24 m s-1, which is 5.3% lower than the single-parameter algorithm in operational use(Witter and Chelton, 1991) and 2.4% lower than another dual-frequency approach(Chen et al., 2002). Furthermore, the results indicate that the new approach significantly improves the wave-dependent bias compared to the single-parameter algorithm. The capacity of altimeter to retrieve sea surface wind speed appears to be limited for the case of winds below 3 m s-1. The validity of the approach at high winds needs to be further examined in the future study. 展开更多
关键词 ALTIMETER mean square slope DUAL-FREQUENCY wind speed retrieval
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Application of Compactness Detection to Complicated Concrete-Filled Steel Tube by Ultrasonic Method 被引量:1
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作者 杨建江 王飞 +1 位作者 陆苏亮 王川 《Transactions of Tianjin University》 EI CAS 2014年第2期126-132,共7页
An example of using ultrasonic method to detect the compactness of complicated concrete-filled steel tube in certain high-rise building was discussed in this study.Because of the particularity of the complicated concr... An example of using ultrasonic method to detect the compactness of complicated concrete-filled steel tube in certain high-rise building was discussed in this study.Because of the particularity of the complicated concrete-filled steel tubular column,the plane detection method and embedded sounding pipe method were adopted in the process of effectively detecting the column.According to the results of the plane detection method and embedded sounding pipe method,the cementing status of steel tube and concrete can be concluded,which cannot be judged by the hammering method in the rectangular steel tube-reinforced concrete. 展开更多
关键词 ultrasonic method concrete-filled steel tube plane detection method embedded sounding pipe method COMPACTNESS
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Scattering-absorbing method for the detection of 16.7 MeV high-energy pulse gamma
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作者 Tan Xinjian Ouyang Xiaoping Wang Qunshu 《Engineering Sciences》 EI 2009年第3期55-58,共4页
Based on theoretical calculation and Monte Carlo simulation,this paper proposes a new method for the diagnosing of 16.7 MeV high-energy pulse gamma,named "scattering absorption method". The ratio of the sens... Based on theoretical calculation and Monte Carlo simulation,this paper proposes a new method for the diagnosing of 16.7 MeV high-energy pulse gamma,named "scattering absorption method". The ratio of the sensitivity of high-energy gamma to that of the low-energy background gamma can reach 106 to 108 by this new method. The sensitivity of 16.7 MeV high-energy gamma ranges from 10-21 to 10-16 C·cm2. It's better than the traditional method which is based on the magnetic analyzer and Cherenkov detector on some aspects. 展开更多
关键词 high-energy gamma Cherenkov detector scattering absorption method
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Application of high density resistivity method in accuracy of goaf detection
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作者 LIU Huiming LI Guangjie DU Lizhi 《Global Geology》 2011年第2期110-114,共5页
Based on the relationship between the diameter and buried depth of goal, the authors establish the forward modeling by Res2dmod and inverse the model by Res2dinv. Thus, three kinds of models are obtained : the model ... Based on the relationship between the diameter and buried depth of goal, the authors establish the forward modeling by Res2dmod and inverse the model by Res2dinv. Thus, three kinds of models are obtained : the model of single resistivity anomalous body, model of double different distance resistivity anomalous body, and model of layered resistivity anomalous body. Using forward and inversion, the image of detection is simulated, and the reliability is proved by comparing with the engineering examples. 展开更多
关键词 high density resistivity method INVERSION GOAF
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Cloud Top Height Retrieval Using Polarizing Remote Sensing Data of POLDER
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作者 HE Xianqiang BAI Yan PAN Delu ZHU Qiankun GONG Fang 《Atmospheric and Oceanic Science Letters》 2009年第2期73-78,共6页
A retrieval method of cloud top heights using polarizing remote sensing is proposed in this paper. Using the vector radiative transfer model in a coupled atmosphere-ocean system, the factors influencing the upwelling ... A retrieval method of cloud top heights using polarizing remote sensing is proposed in this paper. Using the vector radiative transfer model in a coupled atmosphere-ocean system, the factors influencing the upwelling linear polarizing radiance at top-of-atmosphere are analyzed, which show that the upwelling linear polarizing radiance varies remarkably with the cloud top height, but has negligible sensitivity with cloud albedo and aerosol scattering above the cloud layer. Based on this property, a cloud top height retrieval algorithm using polarizing remote sensing was developed. The algorithm has been applied to the polarizing remote sensing data of Polarization and Directionality of the Earth's Reflectances-2 (POLDER-2). The retrieved cloud top height from POLDER-2 compares well with the Moderate Resolution Imaging Spectroradiometer (MODIS) operational product with a bias of 0.83 km and standard deviation of 1.56 km. 展开更多
关键词 cloud top height polarizing remote sensing Polarization and Directionality of the Earth's Reflectances
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Variations of DON Content in Grain during Wheat Tempering at Different Temperatures
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作者 Zhiming GENG Dan YANG +5 位作者 Pingping ZHANG Miaoping ZHOU Daoying WANG Fang LIU Muhan ZHANG Yongzhi ZHU 《Agricultural Science & Technology》 CAS 2014年第4期546-549,共4页
[Objective] The aim of this study was to observe variations of DON content in grain of two wheat cultivars during tempering at different temperatures, and explore the possible causes of the variations. [Method] Two na... [Objective] The aim of this study was to observe variations of DON content in grain of two wheat cultivars during tempering at different temperatures, and explore the possible causes of the variations. [Method] Two naturally Fusarium-infested wheat samples Youmai 3 and Yangmai 14 were selected as experimental materials. Tempering was carried out at different temperature (15, 25 and 35 ℃) for 48 h. During tempering, wheat grain samples were collected every 8 h. DON contents in tempered grain were measured by HPLC coupled with UV detector. [Result] For Youmai 3, DON contents were in the ranges of 3.94-12.49, 4.26-6.11 and 3.41- 7.91 μg/g during tempering at 15, 25 and 35 ℃, respectively. The highest DON contents were observed at the 32^nd hour at 15 ℃, the 8^th hour at 25 ℃ and the 32^rd hour at 35 ℃, respectively. After tempering for 48 h, DON contents in grain were increased by 175.1%, 27.5% and 7.2%, respectively. For Yangmai 14, DON contents were in the ranges of 0.55-1.56, 0.39-0.77 and 0.57-3.17 μg/g during tempering at 15, 25 and 35 ℃, respectively. The highest DON contents were ob- served at the 24^th hour at 15 ℃, the 40^th hour at 25 ℃ and the 48^th hour at 35 ℃, respectively. After tempering for 48 h, DON contents in grain were increased by 94.5% at 15 ℃ and 456.1% at 35 ℃, respectively, whereas it was decreased by 35.0% at 25 ℃. From the point of view of reducing DON level, 15 ℃ was not rea- sonable for the tempering of both wheat cultivars, and tempering at 35 ℃ for 16 h and tempering at 25 ℃ for 24 h appeared to be desirable for Youmai 3 and Yang- mai 14, respectively. [Conclusion] The results suggested controlling the tempering temperature and time would be helpful to reduce DON level in grain. 展开更多
关键词 FUSARIUM DEOXYNIVALENOL CEREALS Wheat tempering
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Determination of amino acid neurotransmitters in mouse brain tissue using high-performance liquid chromatography with fluorescence detection 被引量:3
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作者 王萌萌 杜望春 +3 位作者 沈杰 董毅 魏文石 宋钟娟 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第3期239-243,共5页
Amino acid neurotransmitters facilitate the transmission of nerve messages across the synapses and play essential roles in the control and regulation of a variety of functions in the central and peripheral nervous sys... Amino acid neurotransmitters facilitate the transmission of nerve messages across the synapses and play essential roles in the control and regulation of a variety of functions in the central and peripheral nervous system. In this study, we developed a sensitive and efficient method using high-performance liquid chromatography (HPLC) with fluorescence detection for the assay of five important amino acid n After derivatization with o-phthaldialdehyde (OPA), aspartate (Asp), glutamic acid (Glu), glycine (Gly), taurine (Tau) and ),-aminobutyric acid (GABA) were simultaneously detected in the presence of the internal standard homoserine (Hse). Precise separation of these five amino acids was achieved using isocratic elution within 24 min. Good linearity was found over the concentration range with correlation coefficients (r2) not less than 0.9998. The limit of detection (LOD) values were no more than 10 nmol/L. The intra- and inter-day reproducibility was adequate with the relative standard deviation (RSD) of 10.5% or below. This method has also been applied to the analysis of amino acids in the substantia nigra and striatum samples obtained from C57BL/6 mice. 展开更多
关键词 HPLC Fluorescence detection O-PHTHALDIALDEHYDE Amino acids
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Quantitative determination of ilexgenin A in rat plasma by liquid chromatography coupled with mass spectrometry and its pharmacokinetics 被引量:2
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作者 柳文媛 李萍 +2 位作者 冯锋 余成霞 丁黎 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第1期38-42,共5页
A sensitive and selective high performance liquid chromatography coupled with electrospray ionization mass spectrometry (LC-MS) was developed for the quantitative determination of ilexgenin A (IA),a major componen... A sensitive and selective high performance liquid chromatography coupled with electrospray ionization mass spectrometry (LC-MS) was developed for the quantitative determination of ilexgenin A (IA),a major component in Radix Ilicis Pubescentis,in rat plasma.Chromatographic separation was performed on a C 18 column,with methanol-5 mM ammonium acetate (80:20,v/v) as the mobile phase.Mass spectrometer was set in negative mode with target ions at m/z 501.1→501.1 for IA and m/z 779.4→779.4 for digoxin (internal standard,IS).Rat plasma was extracted with ethyl acetate after addition of phosphoric solution and the organic layer was evaporated and reconstituted with mobile phase for LC-MS analysis.The proposed method was validated with a linear range of 1.05-525.5 ng/mL for IA with limit of quantitation (LOQ) at 1.05 ng/mL.Intra-and inter-day precision expressed as relative standard deviation (RSD) were less than 10% at LOQ level and overall recovery was over 80%.This validated method was used successfully for the pharmacokinetic study of IA in rats after oral dosing of IA (100 mg/kg) and some main pharmacokinetic parameters of IA in rats were obtained. 展开更多
关键词 High performance liquid chromatography Electrospray ionization mass spectrometry Ilexgenin A Radix Ilicis Pubescentis Pharmacokinetic study
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