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
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
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
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
In order to quantify the effect of matrix shrinkage on reservoir permeability during coalbed methane production, coal samples from Huozhou, Changzhi and Jincheng areas in Shanxi province (classified as high-volatile ...In order to quantify the effect of matrix shrinkage on reservoir permeability during coalbed methane production, coal samples from Huozhou, Changzhi and Jincheng areas in Shanxi province (classified as high-volatile bituminous coal, low-volatile bituminous coal and anthracite, respectively) were collected, and adsorption-induced coal swelling in methane were determined by an optical method at 40 ℃ and pressure up to 12 MPa. All three coals showed similar behavior-that swelling increased as a function of pressure up to about 10 MPa but thereafter no further increase in swelling was observed. Swelling in the direction perpendicular to the bedding plane is greater than that parallel to the bedding plane, and the differences are about 7.77-8.33%. The maximum volumetric swelling ranges from 2.73% to 3.21 %-increasing with increasing coal rank. The swelling data can be described by a modified DR model. In addition, swelling increases with the amount of adsorption. However, the increase shows a relatively slower stage followed by a relatively faster stage instead of a linear increase. Based on the assumption that sorption-induced swelling/shrinkage of coal in methane is reversible, the permeability increases induced by coal shrinkage during methane desorption was analyzed, and the results indicate that the permeability change is larger for higher rank coal in the same unit of pressure depletion.展开更多
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
A new kinetic spectrophotometric method has been developed for the determination of trace Ni (Ⅱ in natural water. The method is based on the catalytic effect of Ni (Ⅱ) on the oxidation of weak acid brilliant blue...A new kinetic spectrophotometric method has been developed for the determination of trace Ni (Ⅱ in natural water. The method is based on the catalytic effect of Ni (Ⅱ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The concentration of nickel (Ⅱ) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ = 626 nm using the fix-time method. The influencing factors are investigated by the orthogonal experimental design. The obtained optimum analytical conditions are: pH = 2.00, CRAWL = 5.00×10^-5 mol·L^-1, c KlO4 = 2.00× 10^-5 mol·L^-1, the reaction time t= 10min and the temperature T = 25 ℃. Under the optimum conditions, the developed method allows the measurement of Ni (Ⅱ) in a range of 0 - 40.0ngmL1. The standard deviation of eleven independent measurements of blank reaction is S = 3.08× 10^-3 and the limit of detection is 2.20ng·mL^-1. The relative standard deviations (RSDs) in six replicate determinations of 5 ngmL-1 and 8 ngmL1 Ni (Ⅱ) are 2.87% and 1.11%, respectively. Moreover, the experiments show few cations and anions can interfere with the measurement of Ni (Ⅱ). The recovery efficiencies of this method are in a range of 97.0%-102.5% in freshwater samples. But there is a decreasing effect, which is about 0.2 times the added Ni (Ⅱ) in seawater medium. After reasonable calibration this processing method is used for the determination of Ni (Ⅱ) in seawater samples successfully. The results show this developed method has high accuracy and precision, high sensitivity, large range of linearity and high speed. The method can, therefore, be employed at room temperature.展开更多
A new kinetic spectrophotometric method has been developed for the determination of vanadium(V).The method is based on the catalytic effect of vanadium(V)on the oxidation of weak acid brilliant blue dye(RAWL)by ...A new kinetic spectrophotometric method has been developed for the determination of vanadium(V).The method is based on the catalytic effect of vanadium(V)on the oxidation of weak acid brilliant blue dye(RAWL)by KBrO3 using the citric acid as activation reagent.The obtained optimum conditions are:c(RAWL)= 1×10-4 molL-1,c(KBrO3)= 3×10-2 molL-1,c(citric acid)=9×10-3 molL-1,pH = 2.50,the reaction time being 7.0min and the temperature being 25.0℃.Under the optimum conditions,the proposed method allows the determination of vanadium(V)in the range of 0-70.0ng mL-1 and the detection limit is down to 0.407 ng mL-1.For standard vanadium(V)solution determination,the recovery efficiency is in the range of 98.5%-102% and the RSD ranges from 0.76%-1.25%.Moreover,it is demonstrated that most cations and anions do not interfere with the determination of vanadium(V)under the analytical condition.The new method was successfully applied in the determination of vanadium(V)in fresh water and seawater samples with satisfactory results.Vanadium(V)in the seawater samples from Qingdao offshore was determined using the method and the distribution of vanadium(V)was mapped.Compared with other instrumental analytical methods,the proposed method shows good selectivity,sensitivity,simplicity,lower cost and rapidity.It can be employed on shipboard easily.展开更多
文摘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.
基金Project(20235020) supported by the National Natural Science Foundation of China
文摘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.
基金Advanced Fund Item of Jiangsu University (07KJB610021)
文摘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.
基金supported by grants from the University Grants Commission and partially from UGC-SAP and DST-FIST,Government of India
文摘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.
基金funded by the National Key Technology Support Program of China (No. 2014BAC18B02)the National Natural Science Foundation of China (Nos. 41272176 and 41202116)
文摘In order to quantify the effect of matrix shrinkage on reservoir permeability during coalbed methane production, coal samples from Huozhou, Changzhi and Jincheng areas in Shanxi province (classified as high-volatile bituminous coal, low-volatile bituminous coal and anthracite, respectively) were collected, and adsorption-induced coal swelling in methane were determined by an optical method at 40 ℃ and pressure up to 12 MPa. All three coals showed similar behavior-that swelling increased as a function of pressure up to about 10 MPa but thereafter no further increase in swelling was observed. Swelling in the direction perpendicular to the bedding plane is greater than that parallel to the bedding plane, and the differences are about 7.77-8.33%. The maximum volumetric swelling ranges from 2.73% to 3.21 %-increasing with increasing coal rank. The swelling data can be described by a modified DR model. In addition, swelling increases with the amount of adsorption. However, the increase shows a relatively slower stage followed by a relatively faster stage instead of a linear increase. Based on the assumption that sorption-induced swelling/shrinkage of coal in methane is reversible, the permeability increases induced by coal shrinkage during methane desorption was analyzed, and the results indicate that the permeability change is larger for higher rank coal in the same unit of pressure depletion.
基金supported by the National Natural Science Foundation of China(Grant No.49976020).
文摘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.
文摘A new kinetic spectrophotometric method has been developed for the determination of trace Ni (Ⅱ in natural water. The method is based on the catalytic effect of Ni (Ⅱ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The concentration of nickel (Ⅱ) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ = 626 nm using the fix-time method. The influencing factors are investigated by the orthogonal experimental design. The obtained optimum analytical conditions are: pH = 2.00, CRAWL = 5.00×10^-5 mol·L^-1, c KlO4 = 2.00× 10^-5 mol·L^-1, the reaction time t= 10min and the temperature T = 25 ℃. Under the optimum conditions, the developed method allows the measurement of Ni (Ⅱ) in a range of 0 - 40.0ngmL1. The standard deviation of eleven independent measurements of blank reaction is S = 3.08× 10^-3 and the limit of detection is 2.20ng·mL^-1. The relative standard deviations (RSDs) in six replicate determinations of 5 ngmL-1 and 8 ngmL1 Ni (Ⅱ) are 2.87% and 1.11%, respectively. Moreover, the experiments show few cations and anions can interfere with the measurement of Ni (Ⅱ). The recovery efficiencies of this method are in a range of 97.0%-102.5% in freshwater samples. But there is a decreasing effect, which is about 0.2 times the added Ni (Ⅱ) in seawater medium. After reasonable calibration this processing method is used for the determination of Ni (Ⅱ) in seawater samples successfully. The results show this developed method has high accuracy and precision, high sensitivity, large range of linearity and high speed. The method can, therefore, be employed at room temperature.
文摘A new kinetic spectrophotometric method has been developed for the determination of vanadium(V).The method is based on the catalytic effect of vanadium(V)on the oxidation of weak acid brilliant blue dye(RAWL)by KBrO3 using the citric acid as activation reagent.The obtained optimum conditions are:c(RAWL)= 1×10-4 molL-1,c(KBrO3)= 3×10-2 molL-1,c(citric acid)=9×10-3 molL-1,pH = 2.50,the reaction time being 7.0min and the temperature being 25.0℃.Under the optimum conditions,the proposed method allows the determination of vanadium(V)in the range of 0-70.0ng mL-1 and the detection limit is down to 0.407 ng mL-1.For standard vanadium(V)solution determination,the recovery efficiency is in the range of 98.5%-102% and the RSD ranges from 0.76%-1.25%.Moreover,it is demonstrated that most cations and anions do not interfere with the determination of vanadium(V)under the analytical condition.The new method was successfully applied in the determination of vanadium(V)in fresh water and seawater samples with satisfactory results.Vanadium(V)in the seawater samples from Qingdao offshore was determined using the method and the distribution of vanadium(V)was mapped.Compared with other instrumental analytical methods,the proposed method shows good selectivity,sensitivity,simplicity,lower cost and rapidity.It can be employed on shipboard easily.