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有机无机肥配施黑土胡敏酸结构光谱学特征 被引量:3
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作者 张久明 周宝库 +4 位作者 魏丹 迟凤琴 郝小雨 金梁 匡恩俊 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第3期845-850,共6页
土壤有机质是土壤的重要组成部分,在土壤肥力、环境保护、农业可持续发展等方面都具有重要作用。腐殖质作为土壤有机质的主体,对土壤的一系列性质和形态产生影响,其数量、组成和性质可以反映一定的成土条件和过程,是土壤肥力的重要指标... 土壤有机质是土壤的重要组成部分,在土壤肥力、环境保护、农业可持续发展等方面都具有重要作用。腐殖质作为土壤有机质的主体,对土壤的一系列性质和形态产生影响,其数量、组成和性质可以反映一定的成土条件和过程,是土壤肥力的重要指标。由于腐殖质分子组成的不确定性,各种方法均存在一定的局限性,优化寻求更为准确可靠的腐殖酸表征方法已成为当前研究的热点。施肥方式改变土壤中胡敏酸的组成与结构,但短期的影响程度难以用常规的测定技术检测出来。利用38年的黑土长期定位试验,通过腐殖质组分HA的分离和纯化,多种光谱分析方法的联合应用,从物质结构的角度分析土壤中单施有机肥和有机无机肥配施对黑土HA有机化合物的分子结构变化的影响。分析显示, M和MNPK施肥处理较CK处理均可提高土壤有机碳和HA含量,增加土壤中HA的总反应热、中温放热值、 2920/1720值、脂族C含量、 f450/500值,表明单施有机肥和有机无机肥配施后土壤HA芳构化程度降低,脂族含量增加,结合简单化,但M施肥处理增加幅度小于MNPK施肥处理。分析结果表明:多种光谱技术的联合应用,可以相互认证其结果的准确性。同时试验结果也证明有机无机肥配施较单施有机肥,更能提高土壤有机碳和土壤HA的脂族C含量,增加作物产量,培肥地力。 展开更多
关键词 黑土 土壤腐殖质 光谱学测定 变化特征
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Determination of constituents of essential oil from Angelica sinensis by gas chromatographymass spectrometry 被引量:13
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作者 吴名剑 孙贤军 +3 位作者 戴云辉 郭方遒 黄兰芳 梁逸曾 《Journal of Central South University of Technology》 EI 2005年第4期430-436,共7页
Gas chromatographymass spectrometry (GC-MS) coupled with chemometric resolution upon two- dimensional data was employed to analyze the constituents of essential oils of Angelica sinensis. Constituents in essential oil... Gas chromatographymass spectrometry (GC-MS) coupled with chemometric resolution upon two- dimensional data was employed to analyze the constituents of essential oils of Angelica sinensis. Constituents in essential oils of Angelica sinensis root were identified by GC-MS with the help of subwindow factor analysis (SFA) method resolving two-dimensional original data into mass spectra and chromatograms. 76 of 97 separated constituents in essential oil of Angelica sinensis root were identified and quantified, and they account for about 91.36% of the total content. The results show that ligustilide, butylene phthalide, 2-methoxy-4-vinylphenol, carvacrol, allo-ocimene,2,6,6-trimethylbicyclo-[3,1,1]hept-2-ene are the main constituents in essential oil of Angelica sinensis root. 展开更多
关键词 Angelica sinensis CHEMOMETRICS gas chromatography- mass spectrometry subwindow factor analysis
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Analysis of volatile chemical components of Radix Paeoniae Rubra by gas chromatography-mass spectrometry and chemometric resolution 被引量:11
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作者 李晓如 兰正刚 梁逸曾 《Journal of Central South University of Technology》 2007年第1期57-61,共5页
The volatile chemical components of Radix Paeoniae Rubra (RPR) were analyzed by gas chromatography-mass spectrometry with the method of heuristic evolving latent projections and overall volume integration. The results... The volatile chemical components of Radix Paeoniae Rubra (RPR) were analyzed by gas chromatography-mass spectrometry with the method of heuristic evolving latent projections and overall volume integration. The results show that 38 volatile chemical components of RPR are determined, accounting for 95.21% of total contents of volatile chemical components of RPR. The main volatile chemical components of RPR are (Z, Z)-9,12-octadecadienoic acid, n-hexadecanoic acid, 2-hydroxy- benzaldehyde, 1-(2-hydroxy-4-methoxyphenyl)-ethanone, 6,6-dimethyl-bicyclo[3.1.1] heptane-2-methanol, 4,7-dimethyl-benzofuran, 4-(1-methylethenyl)-1-cyclohexene-1-carboxaldehyde, and cyclohexadecane. 展开更多
关键词 Radix Paeoniae Rubra volatile chemical components gas chromatography-mass spectrometry heuristic evolving latent projections
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FLAME ATOMIC ABSORPTION DETERMINATION OF COPPER IN CEREALS FOOD SAMPLES WITH THE PRECONCENTRATION OF POTASSIUM TETRATITANATE WHISKER 被引量:1
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作者 XU Wanzhen ZHANG Xinghua +2 位作者 YAN Yongsheng LIU Aiqin JING Junjie 《Chinese Journal of Reactive Polymers》 2007年第1期22-30,共9页
A simple and reliable method has been developed for separation and preconcentration of trace amounts of copper ions in cereals food for subsequent measurement by flame atomic absorption spectrometry (FAAS). The Cu^2... A simple and reliable method has been developed for separation and preconcentration of trace amounts of copper ions in cereals food for subsequent measurement by flame atomic absorption spectrometry (FAAS). The Cu^2+ ions are adsorbed selectively and quantitatively during the passage. The retained copper ions were desorbed from the potassium tetratitanate whisker with 10.0mL of 2mol/L sulphuric acid solutions as eluent and were determined by FAAS. The linear range was 0.05μg/mL-0.20μg/mL in the original solution with a correlation coefficient of 0.9998. The detection limit of the proposed method is 2. lng/mL in the original solution (3σ, n=9). Determination of copper in standard ions showed that the proposed method has good accuracy (recovery was more than 95%). The method was successfully applied for recovery and determination of copper in cereals food samples 展开更多
关键词 Flame atomic absorption spectrometry COPPER Cereals food Potassium tetratitanate whisker.
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Detection of α_(2u)-globulin in rat pup preputial gland by MALDI-TOF mass spectrometry
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作者 Ponnirul PONMANICKAM Gnanasekaran JEBAMERCY +1 位作者 Govindaraju ARCHUNAN Soundrapandian KANNAN 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第4期296-300,共5页
The α_ 2u-globulin,a soluble protein identified in the urine and preputial gland of adult male rat is reported to be pheromone carrier.The pup preputial gland plays a significant role in chemical communication for mo... The α_ 2u-globulin,a soluble protein identified in the urine and preputial gland of adult male rat is reported to be pheromone carrier.The pup preputial gland plays a significant role in chemical communication for mother-young interaction;however,the presence of a pheromone-carrying protein in the pup preputial gland has not been confirmed.Therefore,the present study was carried out to identify the α_ 2u-globulin in the pup preputial gland by Matrix Assisted Laser Desorption Ionization Time of Flight mass spectrometry(MALDI-TOF).The preputial glands of prepubertal rats were subjected to one-dimensional SDS-PAGE.In-gel trypsin digestion of a 18 kDa band was carried out and analyzed by MALDI-TOF.The results of a MASCOT search showed the presence of α_ 2u-globulin in the 18 kDa band.In contrast to the report of the synthesis of this protein only in adult rats,the identification of this protein in pup preputial gland is significant.The results suggest that synthesis of α_ 2u-globulin in the rat preputial gland starts in the prepubertal stage itself.In prepubertal rats,the preputial gland is a source of pheromone for performing anogenital licking behaviour by the mother rat.Since α_ 2u-globulin belongs to the lipocalin(ligand carrier)family,it might carry the volatile for processing pheromonal communication in mother-pup bonding in rat. 展开更多
关键词 α2u-globulin MALDI-TOF Pheromone carrying protein Pup preputial gland RAT
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STUDY ON THE DETERMINATION OF TRACE Fe(Ⅲ) BY THIN LAYER RESIN PHASE SPECTROPHOTOMETRY
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作者 HOU Yanmin YANG Yongsheng +1 位作者 XIE Jimin HUANG Weihong 《Chinese Journal of Reactive Polymers》 2007年第1期80-84,共5页
A method to determine Fe(Ⅲ) by thin layer resin phase spectrophotometry has been developed in this paper. The colored complex formed by Fe(Ⅲ) and 1,2-benzendiol is concentrated on the 717^# resin, then Fe(Ⅲ) ... A method to determine Fe(Ⅲ) by thin layer resin phase spectrophotometry has been developed in this paper. The colored complex formed by Fe(Ⅲ) and 1,2-benzendiol is concentrated on the 717^# resin, then Fe(Ⅲ) can be determined directly by making thin layer. The method is sensitive with a apparent molar absorption of 4.8×10^4L/mol.cm, which is 16 times higher than that of liquid phase spectrophotornetry, most coexisting ions do not influence the determination. The detection limit for Fe(Ⅲ) is 1.47μg/L with the precision of 3.3% [n=6, 7μg/50mL Fe(Ⅲ)]. The calibration curve is linear in the range of 0-25μg/50mL. The preposed method was applied to the determination of Fe(Ⅲ) in water sample with satisfactory results. 展开更多
关键词 1 2-benzendiol Thin layer resin phase spectrophotometry Fe(Ⅲ).
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Concentrations and Distribution of Trace Metals of PM10 and TSP Particles Collected in the Qingdao Area 被引量:1
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作者 LI Xianguo, FENG Lijuan, QI Jianhua, CHEN Xingmao, ZHANG ManpingCollege of Chemistry & Chemical Engineering, Ocean University of China, Qingdao 266003, P.R.China 《Journal of Ocean University of Qingdao》 2003年第2期189-194,共6页
Aerosol samples of PM10 (particulate matter with aerodynamic diameters less than 10μm) and TSP (total suspended particles) were simultaneously collected from April 2001 to March 2002 at the top of Mount Baguan on the... Aerosol samples of PM10 (particulate matter with aerodynamic diameters less than 10μm) and TSP (total suspended particles) were simultaneously collected from April 2001 to March 2002 at the top of Mount Baguan on the downtown campus of Ocean University of China, Qingdao, China. The concentrations of Al, Fe, Mn, Cu, Pb and Zn were determined by means of inductively coupled plasma atomic emission spectrometry (ICP-AES). The monthly variability of the mass concentrations of aerosol particles and the concentrations of trace metals are presented and discussed. The distribution pattern of these metals in PM10 and TSP is also discussed. During the observation period, the mass concentration of PM10 at this site ranged from 13.80 to 306.42μgm-3 , while that of TSP ranged from 31.02 to 568.82μgm-3. Both PM10 and TSP reached their highest concentrations in springtime, while the lowest values occurred in summertime. The concentrations of crustal metals followed the same variation pattern, while those of anthropogenic metals did not. A closer examination led to the conclusion that anthropogenic metals are mainly from local sources. The average concentration ratios of anthropogenic metals in PM10 to TSP were higher than the average mass ratio of PM10 to TSP, suggesting that there was a higher proportion of anthropogenic metals on smaller particles although there were a few exceptions. For crustal metals, however, the metal concentration ratios were close to the particle mass ratio, indicating that the distribution of crustal metals was much more homogeneous on aerosol particles with different sizes. The correlation analysis indicated that Al, Fe and Mn were originated from similar sources and were mainly controlled by the particle mass, while Cu, Pb and Zn were predominated by local anthropogenic sources, with Pb and Zn having similar origins. 展开更多
关键词 PM_(10) TSP trace metal concentration DISTRIBUTION Qingdao
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Modified Fisheye Optical System
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作者 Suha Mousa Khorsheed Al-Awsi Nour Mohammed Hasan Yaseen 《Journal of Physical Science and Application》 2016年第1期56-60,共5页
A design for a fisheye optical system is modified in order to enable IR vision in addition to the visible and UV lighting. The proposed modification goes to replace the optical material of the movable lens by another ... A design for a fisheye optical system is modified in order to enable IR vision in addition to the visible and UV lighting. The proposed modification goes to replace the optical material of the movable lens by another with less thermal dispersion. The choice of appropriate materials lead to a good focus appeared on the retina for a wide spectral range includes UV, visible, and near IR lighting. Then, the performance of the modified design is verified through some optical measures for imaging quality determinations. These optical measures are determined with the aid of Zemax software, which also used for testing performance of the modified fisheye optical system. The analysis mainly focuses on the energy distribution in the light spot on the focal surface. The results show that the modified design of the fisheye is acceptable. 展开更多
关键词 FISHEYE optical system IR-vision.
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Chemometrics-assisted excitation-emission fluorescence spectroscopy for simultaneous determination of ethoxyquin and tert-butylhydroquinone in biological fluid samples 被引量:2
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作者 CHEN Yao WU HaiLong +4 位作者 WANG JianYao ZHANG XiaoHua LI Yong ZHANG ShuRong YU Ru-Qin 《Science China Chemistry》 SCIE EI CAS 2013年第5期664-671,共8页
A novel method applying simple, rapid, effective and inexpensive excitation-emission matrix (EEM) fluorescence spectroscopy coupled with second-order calibration method for simultaneous determination of ethoxyquin ... A novel method applying simple, rapid, effective and inexpensive excitation-emission matrix (EEM) fluorescence spectroscopy coupled with second-order calibration method for simultaneous determination of ethoxyquin (EQ) and tert-butylhydroquinone (TBHQ) contents in biological fluid samples was developed. After a simple data preprocessing that was to insert zeros below the first-order Rayleigh scattering, the second-order calibration method based on the alternating normalization-weighed error (ANWE) algorithm was used to deal with EEM data. Via the introduced "second-order advantage", the individual con- centrations of the analytes of interest could be obtained even in the presence of uncalibrated interferences. The experimental concentration ranges for the analytes were as follows: EQ, from 4.58 to 20.6 p.g mL-1 in plasma and from 6.87 to 20.6 gg mL-1 in urine; TBHQ, from 4.49 to 20.2 ~tg mL-1 in plasma and from 6.73 to 22.4 I.tg mL-l in urine. The recoveries from spiked bi- ological fluid samples were in the ranges of 92.8%-106.2% for EQ and 94.6%-107.2% for TBHQ. These results demonstrate that the three-dimensional EEM fluorescence with second-order calibration method is a powerful tool for obtaining both EQ and TBHQ quantitative results in plasma and urine samples, and could be applied to more complex matrices. 展开更多
关键词 ethoxyquin TERT-BUTYLHYDROQUINONE biological fluid samples fluorescence alternating normalization-weighed error
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