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considerations for semi-quantification of total naphthenic acids in oil sands process affected water by massspectrometry: A review

Kevin A. Kovalchik, Matthew S. MacLennan, Kerry M. Peru, John V. Headley, David D.Y. Chen

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 497-507 doi: 10.1007/s11705-017-1652-0

摘要: Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semi-quantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi-quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada (ECCC) led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. Matters considered are: extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.

关键词: total naphthenic acids     environmental samples     oil sands process affected water     polar organics     mass spectrometry    

Peroxyacetyl nitrate measurements by thermal dissociation–chemical ionization mass spectrometry in an

Xinfeng Wang, Tao Wang, Likun Xue, Wei Nie, Zheng Xu, Steven C. N. Poon, Wenxing Wang

《环境科学与工程前沿(英文)》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0925-7

摘要: Peroxyacetyl nitrate (PAN) is an important indicator of photochemical smog and has adverse effects on human health and vegetation growth. A rapid and highly selective technique of thermal dissociation–chemical ionization mass spectrometry (TD-CIMS) was recently developed to measure the abundance of PAN in real time; however, it may be subject to artifact in the presence of nitric oxide (NO). In this study, we tested the interference of the PAN signal induced by NO, evaluated the performance of TD-CIMS in an urban environment, and investigated the concentration and formation of PAN in urban Hong Kong. NO caused a significant underestimation of the PAN signal in TD-CIMS, with the underestimation increasing sharply with NO concentration and decreasing slightly with PAN abundance. A formula was derived to link the loss of PAN signal with the concentrations of NO and PAN, which can be used for data correction in PAN measurements. The corrected PAN data from TD-CIMS were consistent with those from the commonly used gas chromatography with electron capture detection, which confirms the utility of TD-CIMS in an urban environment in which NO is abundant. In autumn of 2010, the hourly average PAN mixing ratio varied from 0.06 ppbv to 5.17 ppbv, indicating the occurrence of photochemical pollution in urban Hong Kong. The formation efficiency of PAN during pollution episodes was as high as 3.9 to 5.9 ppbv per 100 ppbv ozone. PAN levels showed a near-linear increase with NO concentration, suggesting a control policy of NO reduction for PAN pollution.

关键词: TD-CIMS     Peroxyacetyl nitrate     Interference     Photochemical pollution     Formation efficiency    

Metabolomics in human type 2 diabetes research

null

《医学前沿(英文)》 2013年 第7卷 第1期   页码 4-13 doi: 10.1007/s11684-013-0248-4

摘要:

The high prevalence of diabetes and diabetic complications has caused a huge burden on the modern society. Although scientific advances have led to effective strategies for preventing and treating diabetes over the past several decades, little progress has been made toward curing the disease or even getting it under control, from a public health and overall societal standpoint. There is still a lack of reliable biomarkers indicative of metabolic alterations associated with diabetes and different drug responses, highlighting the need for the development of early diagnostic and prognostic markers for diabetes and diabetic complications. The emergence of metabolomics has allowed researchers to systemically measure the small molecule metabolites, which are sensitive to the changes of both environmental and genetic factors and therefore, could be regarded as the link between genotypes and phenotypes. During the last decade, the progression made in metabolomics has provided insightful information on disease development and disease onset prediction. Recent studies using metabolomics approach coupled with statistical tools to predict incident diabetes revealed a number of metabolites that are significantly altered, including branched-chain and aromatic amino acids, such as isoleucine, leucine, valine, tyrosine and phenylalanine, as diagnostic or highly-significant predictors of future diabetes. This review summarizes the current findings of metabolomic studies in human investigations with the most common form of diabetes, type 2 diabetes.

关键词: metabolomics     type 2 diabetes     metabolic pathway     mass spectrometry     nuclear magnetic resonance (NMR)    

five taste and odor compounds in surface water using solid-phase extraction and gas chromatography-massspectrometry

Wenfeng SUN, Ruibao JIA, Baoyu GAO

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 66-74 doi: 10.1007/s11783-010-0257-3

摘要: In this paper, a method using solid-phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) was developed to simultaneously analyze five taste and odor compounds in surface water, i.e., 2-methylisoborneol (2-MIB), 2,4,6-trichloroanisole (TCA), 2-isopropyl-3-methoxy pyrazine (IPMP), 2-isobutyl-3-methoxy pyrazine (IBMP), and -1,10-dimethyl- -9-decalol (geosmin, GSM). The mass spectrometry was operated in selective ion monitoring (SIM) mode. Three kinds of SPE columns and three eluting solvents were compared, the C18 column was chosen as optimum SPE column, and methanol was chosen as the optimum eluting solvent. It was found that the method showed good linearity in the range of 1–200 ng·L and gave detection limits of 0.5–1.5 ng·L for individual compounds. Good recoveries (93.5%–108%) and relative standard deviations (1.58%–7.31%) were also obtained. Additionally, concentrations of these taste and odor compounds in Jinan’s surface and drinking water were analyzed by applying this method, and the results showed that GSM and 2-MIB were the dominant taste and odor compounds in Jinan’s raw water.

关键词: solid-phase extraction (SPE)     gas chromatography-mass spectrometry (GC-MS)     taste and odor compounds     surface water     micropollutant    

several classes of antibiotics in water, sediments, and fish muscles by liquid chromatography–tandem massspectrometry

WEI Yimei,ZHANG Yuan,XU Jian,GUO Changsheng,LI Lei,FAN Wenhong

《环境科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 357-371 doi: 10.1007/s11783-013-0580-6

摘要: Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%–95.8%, 48.1%–105.3%, and 59.8%–103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng·L (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfloxacin was the highest (up to 38.5 μg·kg ), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.

关键词: antibiotics     liquid chromatography–tandem mass spectrometry (LC-MS/MS)     water     sediment     fish muscle    

Application of proteomics in environmental science

Xiaona CHU, Jiangyong HU, Say Leong ONG,

《环境科学与工程前沿(英文)》 2009年 第3卷 第4期   页码 393-403 doi: 10.1007/s11783-009-0145-x

摘要: Proteomics involves the separation of proteins, identification of the amino acid sequence of the interested or target proteins, study of the function of the proteins, modification, structure and ultimate assignments to functional pathways in the cell. The proteomic investigations have contributed greatly to human diseases studies, new drugs discovery researches, and environmental science in recent years. This article provides a review on the development of the main proteomic technologies, including both the gel based and non-gel based technologies, and their applications in environmental science. Proteomic technologies have been utilized in the environmental stresses studies to analyze the induction or reduction of proteins at expression level and identify the target proteins to investigate their function in response to environmental stresses, such as high or low pH, oxidation stress, and toxic chemicals. Such protein responses are also helpful to understand the mechanisms of some cellular activities and the functions of some proteins.

关键词: proteomics     environmental stress     two dimensional (2D) gel electrophoresis     mass spectrometry    

of persistent organic pollutants by gas chromatography/laser multiphoton ionization/time-of-flight massspectrometry

Osamu SHITAMICHI, Taiki MATSUI, Yamei HUI, Weiwei CHEN, Totaro IMASAKA

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 26-31 doi: 10.1007/s11783-011-0374-7

摘要: An authentic mixture of polychlorinated biphenyls was measured using a short wide-bore capillary column for the group separation of major components present in an actual sample of Kanechlor. The limits of detection were improved by ca. 2 fold in comparison with those obtained using a conventional capillary column, since the retention time was reduced and the amount of analytes introduced into the mass spectrometer per unit time could be increased. On the other hand, surface-water and sediment samples containing polycyclic aromatic hydrocarbons (PAHs) were collected from the river located in the vicinity of a waste water treatment plant. Even acenaphthylene, a minor component of the mixture could be measured for the sediment sample, and the concentrations were determined for several heavy PAHs. As demonstrated, a technique involving laser multiphoton ionization/time-of-flight mass spectrometry was useful as a sensitive and selective analytical tool for the trace analysis of persistent organic pollutants in an environmental sample.

关键词: polychlorinated biphenyls (PCBs)     polycyclic aromatic hydrocarbons (PAHs)     laser multiphoton ionization/time-of-flight mass spectrometry (MPI/TOF-MS)    

Detecting

Chengkun WANG, Xiaojian ZHANG, Jun WANG, Chao CHEN

《环境科学与工程前沿(英文)》 2012年 第6卷 第6期   页码 770-777 doi: 10.1007/s11783-012-0412-0

摘要: nitrosodimethylamine (NDMA) and several other nitrosamines have been detected as disinfection by-products in drinking waters in many countries around the world. An ultra-performance liquid chromatography-tandem mass spectrometry method with solid phase extraction sample preparation was developed to study the occurrence of nitrosamines in several water treatment plants and distribution systems in China. Isotope labeled nitrosodi- propylamine-d14 (NDPA-d14) was selected as the internal standard for quantification. The solid phase extraction procedures including pH, enrichment process and MS/MS parameters including capillary voltage, cone gas flow, cone voltage, collision energy were optimized to give average recoveries of 26% to 112% for nine nitrosamine species. The instrument detection limits were estimated to range from 0.5 to 5 μg·L for the nine nitrosamine species. NDMA and several other nitrosamines were found at fairly high concentrations in several water treatment plants and distribution systems. NDMA was found in all locations, and the highest concentrations in cities B, G, T, and W were 3.0, 35.7, 21.3, and 19.7 ng·L , respectively. A wide range of nitrosamines concentrations and species were observed in different locations. Higher concentrations of nitrosamines were detected in distribution systems that were further away from the treatment plants, suggesting that the contact time between the residual disinfectant and natural organic matter may play an important role in the formation of these compounds.

关键词: N-nitrosamines     water treatment plant     distribution system     ultra-performance liquid chromatography-tandem mass spectrometry    

using liquid-liquid microextraction coupled with gas chromatography—positive chemical ionization-tandem massspectrometry

Jian LU,Paul S. WILLS,P. CHRIS WILSON

《环境科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 477-481 doi: 10.1007/s11783-015-0820-z

摘要: A rapid, inexpensive and laboratory friendly method was developed for analysis of off-flavor/odor compounds in fresh and salt water using gas chromatography with chemical ionization-tandem mass spectrometry. Off-flavor/odor compounds included geosmin, 2-methylisoborneol (MIB), 2-isobutyl-3-methyoxypyrazine (IBMP), and 2-isopropyl-3-methoxypyrazine (IPMP). Using this method, a single sample can be extracted within minutes using only 1 mL of organic solvent. The ion transitions for IPMP, IBMP, MIB, and geosmin were 153>121, 167>125, 152>95, and 165>109, respectively. The linearity of this method for analyzing MIB ranged from 4 to 200 ng·L , and from 0.8 to 200 ng·L for the other analytes. Method recoveries ranged from 97% to 111% and percent relative standard deviations ranged from 3% to 9%, indicating that the method is accurate, precise, and reliable.

关键词: off-flavor/odor compounds     liquid-liquid microextraction     gas chromatography-tandem mass spectrometry    

Characteristics and removal mechanism of the precursors of N-chloro-2,2-dichloroacetamide in a drinking water treatment process at Taihu Lake

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1338-6

摘要:

• N-Cl-DCAM, an emerging N-DBP in drinking water was investigated.

关键词: N-chloro-2     2-dichloroacetamide     Liquid chromatography with tandem mass spectrometry     Precursors     Removal efficiency     Ozonation integrated with biological activated carbon    

Etiology of invasive candidosis agents in Russia: a multicenter epidemiological survey

null

《医学前沿(英文)》 2018年 第12卷 第1期   页码 84-91 doi: 10.1007/s11684-017-0612-x

摘要:

A multicenter prospective epidemiological survey on the etiologic agents of invasive candidosis was conducted in Russia in the period of 2012–2014. Samples were collected from 284 patients with invasive candidosis and Candida species isolated by culture. The species were identified by DNA sequencing and MALDI-TOF mass-spectrometry. A total of 322 isolates were recovered, in which 96% of Сandida species belonged to six major species, namely, C. albicans (43.2%), C. parapsilosis (20.2%), C. glabrata (11.5%), C. tropicalis (9.6%), C. krusei (6.2%), and C. guilliermondii (5.3%). Most Candida species were isolated from blood samples (83.23%). Notably, the prevalence rate of C. albicans reduced from 52.38% to 32.79% (2012 vs. 2014) (P=0.01) whereas that of non-C. albicans increased from 47.62% (2012) to 67.21% (2014) (P<0.01). Species distribution differed among geographical regions; specifically, the prevalence rate of C. albicans as an etiologic agent of invasive candidosis in Siberian Federal region was significantly higher than that in other Federal regions. Results indicated a shift from C. albicans to non-C. albicans. Therefore, a detailed investigation on the contributing factors and appropriate treatment of invasive candidosis is needed.

关键词: prevalence     &Scy     andida species     invasive candidosis     nosocomial     etiology     MALDI-TOF mass-spectrometry     candidemia    

water using automated online solid-phase extraction with large-volume injection/gas chromatography/massspectrometry

Yongtao LI, Christina L. MCCARTY, Ed J. GEORGE

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 417-425 doi: 10.1007/s11783-011-0310-x

摘要: A rapid, sensitive, and cost-effective analytical method was developed for the analysis of selected semi-volatile organic compounds in water. The method used an automated online solid-phase extraction technique coupled with programmed-temperature vaporization large-volume injection gas chromatography/mass spectrometry. The water samples were extracted by using a fully automated mobile rack system based on x-y-z robotic techniques using syringes and disposable 96-well extraction plates. The method was validated for the analysis of 30 semi-volatile analytes in drinking water, groundwater, and surface water. For a sample volume of 10 mL, the linear calibrations ranged from 0.01 or 0.05 to 2.5μg·L , and the method detection limits were less than 0.1μg·L . For the reagent water samples fortified at 1.0μg·L and 2.0?μg·L , the obtained mean absolute recoveries were 70%–130% with relative standard deviations of less than 20% for most analytes. For the drinking water, groundwater, and surface water samples fortified at 1.0μg·L , the obtained mean absolute recoveries were 50%–130% with relative standard deviations of less than 20% for most analytes. The new method demonstrated three advantages: 1) no manipulation except the fortification of surrogate standards prior to extraction; 2) significant cost reduction associated with sample collection, shipping, storage, and preparation; and 3) reduced exposure to hazardous solvents and other chemicals. As a result, this new automated method can be used as an effective approach for screening and/or compliance monitoring of selected semi-volatile organic compounds in water.

关键词: automated solid-phase extraction     programmed-temperature vaporization     large-volume injection     gas chromatography/mass spectrometry     semi-volatile organic compounds     water analysis    

Metabonomic study of the biochemical profiles of heterozygous myostatin knockout swine

Jianxiang XU,Dengke PAN,Jie ZHAO,Jianwu WANG,Xiaohong HE,Yuehui MA,Ning LI

《农业科学与工程前沿(英文)》 2015年 第2卷 第1期   页码 90-99 doi: 10.15302/J-FASE-2015045

摘要: Myostatin is a transforming growth factor-β family member that normally acts to limit skeletal muscle growth. Myostatin gene ( ) knockout (KO) mice show possible effects for the prevention or treatment of metabolic disorders such as obesity and type 2 diabetes. We applied chromatography and mass spectrometry based metabonomics to assess system-wide metabolic response of heterozygous KO ( ) swine. Most of the metabolic data for swine were similar to the data for wild type (WT) control swine. There were, however, metabolic changes related to fatty acid metabolism, glucose utilization, lipid metabolism, as well as BCAA catabolism caused by monoallelic depletion.The statistical analyses suggested that: (1) most metabolic changes were not significant in swine compared to WT swine; (2) only a few metabolic properties were significantly different between KO and WT swine, especially for lipid metabolism. Significantly, these minor changes were most evident in female KO swine and suggested differences in gender sensitivity to myostatin.

关键词: myostatin     transforming growth factor-β family     skeletal muscle     metabolic disorders     chromatography     mass spectrometry     metabonomics    

Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 59-64 doi: 10.1007/s11783-009-0152-y

摘要: Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis, semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process. This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid oil products.

关键词: oil sludge     pyrolysis     Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy (TG-FTIR)     Pyrolysis-Gas Chromatography/Mass Spectrometry (PY-GC/MS)    

Photocatalytic degradation of methyl orange using ZnO/TiO composites

Ming GE , Changsheng GUO , Xingwang ZHU , Lili MA , Wei HU , Yuqiu WANG , Zhenan HAN ,

《环境科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 271-280 doi: 10.1007/s11783-009-0035-2

摘要: ZnO/TiO composites were synthesized by using the solvothermal method and ultrasonic precipitation followed by heat treatment in order to investigate their photocatalytic degradation of methyl orange (MO) in aqueous suspension under UV irradiation. The composition and surface structure of the catalyst were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), and transmission electron microscopy (TEM). The degradation efficiencies of MO at various pH values were obtained. The highest degradation efficiencies were obtained before 30min and after 60min at pH 11.0 and pH 2.0, respectively. A sample analysis was conducted using liquid chromatography coupled with electrospray ionization ion-trap mass spectrometry. Six intermediates were found during the photocatalytic degradation process of quinonoid MO. The degradation pathway of quinonoid MO was also proposed.

关键词: photocatalytic degradation     methyl orange     ZnO/TiO2 composites     high performance liquid chromatography mass spectrometry (HPLC-MS)    

标题 作者 时间 类型 操作

considerations for semi-quantification of total naphthenic acids in oil sands process affected water by massspectrometry: A review

Kevin A. Kovalchik, Matthew S. MacLennan, Kerry M. Peru, John V. Headley, David D.Y. Chen

期刊论文

Peroxyacetyl nitrate measurements by thermal dissociation–chemical ionization mass spectrometry in an

Xinfeng Wang, Tao Wang, Likun Xue, Wei Nie, Zheng Xu, Steven C. N. Poon, Wenxing Wang

期刊论文

Metabolomics in human type 2 diabetes research

null

期刊论文

five taste and odor compounds in surface water using solid-phase extraction and gas chromatography-massspectrometry

Wenfeng SUN, Ruibao JIA, Baoyu GAO

期刊论文

several classes of antibiotics in water, sediments, and fish muscles by liquid chromatography–tandem massspectrometry

WEI Yimei,ZHANG Yuan,XU Jian,GUO Changsheng,LI Lei,FAN Wenhong

期刊论文

Application of proteomics in environmental science

Xiaona CHU, Jiangyong HU, Say Leong ONG,

期刊论文

of persistent organic pollutants by gas chromatography/laser multiphoton ionization/time-of-flight massspectrometry

Osamu SHITAMICHI, Taiki MATSUI, Yamei HUI, Weiwei CHEN, Totaro IMASAKA

期刊论文

Detecting

Chengkun WANG, Xiaojian ZHANG, Jun WANG, Chao CHEN

期刊论文

using liquid-liquid microextraction coupled with gas chromatography—positive chemical ionization-tandem massspectrometry

Jian LU,Paul S. WILLS,P. CHRIS WILSON

期刊论文

Characteristics and removal mechanism of the precursors of N-chloro-2,2-dichloroacetamide in a drinking water treatment process at Taihu Lake

期刊论文

Etiology of invasive candidosis agents in Russia: a multicenter epidemiological survey

null

期刊论文

water using automated online solid-phase extraction with large-volume injection/gas chromatography/massspectrometry

Yongtao LI, Christina L. MCCARTY, Ed J. GEORGE

期刊论文

Metabonomic study of the biochemical profiles of heterozygous myostatin knockout swine

Jianxiang XU,Dengke PAN,Jie ZHAO,Jianwu WANG,Xiaohong HE,Yuehui MA,Ning LI

期刊论文

Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

期刊论文

Photocatalytic degradation of methyl orange using ZnO/TiO composites

Ming GE , Changsheng GUO , Xingwang ZHU , Lili MA , Wei HU , Yuqiu WANG , Zhenan HAN ,

期刊论文