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Structural Characterization and Octanol/water Partition Coefficients(LogP) Prediction for Oxygen-containing Organic Compounds 被引量:8
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作者 廖立敏 黄茜 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1243-1250,共8页
New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed t... New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed to build two relationship models between the structures and octanol/water partition coefficients(LogP) of the compounds. The modeling correlation coefficients(R) were 0.976 and 0.922, and the "leave one out" cross validation correlation coefficients(R(CV)) were 0.973 and 0.909, respectively. The results showed that the structural descriptors could well characterize the molecular structures of the compounds; the stability and predictive power of the models were good. 展开更多
关键词 oxygen-containing organic compounds octanol/water partition coefficients(LogP) structural descriptors relationship between structures and properties
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Modern approaches for detection of volatile organic compounds in metabolic studies focusing on pathogenic bacteria:Current state of the art 被引量:1
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作者 Karolina Zuchowska Wojciech Filipiak 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期483-505,共23页
Pathogenic microorganisms produce numerous metabolites,including volatile organic compounds(VOCs).Monitoring these metabolites in biological matrices(e.g.,urine,blood,or breath)can reveal the presence of specific micr... Pathogenic microorganisms produce numerous metabolites,including volatile organic compounds(VOCs).Monitoring these metabolites in biological matrices(e.g.,urine,blood,or breath)can reveal the presence of specific microorganisms,enabling the early diagnosis of infections and the timely implementation of tar-geted therapy.However,complex matrices only contain trace levels of VOCs,and their constituent com-ponents can hinder determination of these compounds.Therefore,modern analytical techniques enabling the non-invasive identification and precise quantification of microbial VOCs are needed.In this paper,we discuss bacterial VOC analysis under in vitro conditions,in animal models and disease diagnosis in humans,including techniques for offline and online analysis in clinical settings.We also consider the advantages and limitations of novel microextraction techniques used to prepare biological samples for VOC analysis,in addition to reviewing current clinical studies on bacterial volatilomes that address inter-species in-teractions,the kinetics of VOC metabolism,and species-and drug-resistance specificity. 展开更多
关键词 Volatile organic compounds Pathogenic bacteria metabolites Metabolomics Microextraction techniques Gas chromatography-mass spectrometry In vivo breath analysis In vitro model
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Significant contributions of the petroleum industry to volatile organic compounds and ozone pollution:Insights from year-long observations in the Yellow River Delta
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作者 Jinghao Tang Hengqing Shen +7 位作者 Hong Li Yuanyuan Ji Xuelian Zhong Min Zhao Yuhong Liu Mingzhi Guo Fanyi Shang Likun Xue 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期39-44,共6页
The petroleum industry is a significant source of anthropogenic volatile organic compounds(VOCs),but up to now,its exact impact on urban VOCs and ozone(O_(3))remains unclear.This study conducted year-long VOC ob-serva... The petroleum industry is a significant source of anthropogenic volatile organic compounds(VOCs),but up to now,its exact impact on urban VOCs and ozone(O_(3))remains unclear.This study conducted year-long VOC ob-servations in Dongying,China,a petroleum industrial region.The VOCs from the petroleum industry(oil and gas volatilization and petrochemical production)were identified by employing the positive matrix factorization model,and their contribution to O_(3) formation was quantitatively evaluated using an observation-based chemical box model.The observed annual average concentration of VOCs was 68.6±63.5 ppbv,with a maximum daily av-erage of 335.3 ppbv.The petroleum industry accounted for 66.5%of total VOCs,contributing 54.9%from oil and gas evaporation and 11.6%from petrochemical production.Model results indicated that VOCs from the petroleum industry contributed to 31%of net O_(3) production,with 21.3%and 34.2%contributions to HO_(2)+NO and RO_(2)+NO pathways,respectively.The larger impact on the RO_(2) pathway is primarily due to the fact that OH+VOCs ac-count for 86.9%of the primary source of RO_(2).This study highlights the critical role of controlling VOCs from the petroleum industry in urban O_(3) pollution,especially those from previously overlooked low-reactivity alkanes. 展开更多
关键词 Petroleum industry Volatile organic compounds Ozone pollution Positive matrix factorization Observation-based model
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Identification of breath volatile organic compounds to distinguish pancreatic adenocarcinoma,pancreatic cystic neoplasm,and patients without pancreatic lesions
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作者 Kasenee Tiankanon Nuttanit Pungpipattrakul +2 位作者 Thanikan Sukaram Roongruedee Chaiteerakij Rungsun Rerknimitr 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期894-906,共13页
BACKGROUND Volatile organic compounds(VOCs)are a promising potential biomarker that may be able to identify the presence of cancers.AIM To identify exhaled breath VOCs that distinguish pancreatic ductal adenocar-cinom... BACKGROUND Volatile organic compounds(VOCs)are a promising potential biomarker that may be able to identify the presence of cancers.AIM To identify exhaled breath VOCs that distinguish pancreatic ductal adenocar-cinoma(PDAC)from intraductal papillary mucinous neoplasm(IPMN)and healthy volunteers.METHODS We collected exhaled breath from histologically proven PDAC patients,radiological diagnosis IPMN,and healthy volunteers using the ReCIVA®device between 10/2021-11/2022.VOCs were identified by thermal desorption-gas chromatography/field-asymmetric ion mobility spectrometry and compared between groups.RESULTS A total of 156 participants(44%male,mean age 62.6±10.6)were enrolled(54 PDAC,42 IPMN,and 60 controls).Among the nine VOCs identified,two VOCs that showed differences between groups were dimethyl sulfide[0.73 vs 0.74 vs 0.94 arbitrary units(AU),respectively;P=0.008]and acetone dimers(3.95 vs 4.49 vs 5.19 AU,respectively;P<0.001).After adjusting for the imbalance parameters,PDAC showed higher dimethyl sulfide levels than the control and IPMN groups,with adjusted odds ratio(aOR)of 6.98(95%CI:1.15-42.17)and 4.56(1.03-20.20),respectively(P<0.05 both).Acetone dimer levels were also higher in PDAC compared to controls and IPMN(aOR:5.12(1.80-14.57)and aOR:3.35(1.47-7.63),respectively(P<0.05 both).Acetone dimer,but not dimethyl sulfide,performed better than CA19-9 in PDAC diagnosis(AUROC 0.910 vs 0.796).The AUROC of acetone dimer increased to 0.936 when combined with CA19-9,which was better than CA19-9 alone(P<0.05).CONCLUSION Dimethyl sulfide and acetone dimer are VOCs that potentially distinguish PDAC from IPMN and healthy participants.Additional prospective studies are required to validate these findings. 展开更多
关键词 Volatile organic compound PANCREAS ADENOCARCINOMA Pancreatic intraductal neoplasms Breathing
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Organic Compounds Possessing the Plastic Crystalline Phase: Calculation of Their Fusion Enthalpies
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作者 Mikhail Yu. Gorbachev Natalia N. Gorinchoy 《International Journal of Organic Chemistry》 2024年第3期93-106,共14页
For the first time, for different organic and inorganic compounds possessing the plastic crystalline phase, a new semiempirical equation describing dependence of their fusion enthalpies on such physico-chemical quanti... For the first time, for different organic and inorganic compounds possessing the plastic crystalline phase, a new semiempirical equation describing dependence of their fusion enthalpies on such physico-chemical quantities as normal melting temperature, surface tension, molar volume and critical molar volume is received on the base of the principle of corresponding states and the energy equipartition theorem. Moreover, the proposed equation allows one to take into account the particularities of one-particle molecular rotation in the plastic crystalline phase. 展开更多
关键词 Fusion Enthalpies Calculation organic compounds Inorganic compounds Plastic Crystalline Phases
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Towards green asphalt materials with lower emission of volatile organic compounds: A review on the release characteristics and its emission reduction additives
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作者 Xiwen Chang Feng Wang +2 位作者 Rui Wu Chen Wang Yue Xiao 《Journal of Road Engineering》 2024年第3期292-317,共26页
Recently, researchers in the road field are focusing on the development of green asphalt materials with loweremission of volatile organic compounds (VOCs). The characterization methodology of asphalt VOCs and theinflu... Recently, researchers in the road field are focusing on the development of green asphalt materials with loweremission of volatile organic compounds (VOCs). The characterization methodology of asphalt VOCs and theinfluencing factors on VOCs release have always been the basic issue of asphalt VOCs emission reduction research.Researchers have proposed a variety of asphalt VOCs characterization methodologies, which also have mutuallyirreplaceable characteristics. Asphalt VOCs volatilization is affected by many factors. In this study, asphalt VOCscharacterization methodologies were summarized, including their advantages, disadvantages, characteristics andapplicable requirements. Subsequently, the influencing factors of VOCs release, such as asphalt types and environment conditions, are summarized to provide theoretical support for the emission reduction research. Theclassification and mechanism of newly-development asphalt VOCs emission reduction materials are reviewed. Thereduction efficiencies are also compared to select better materials and put forward the improvement objective ofnew materials and new processes. In addition, the prospects about development of VOCs release mechanism ofasphalt materials during the full life cycle and feasibility research of high-efficiency composite emission reductionmaterials in the future were put forward. 展开更多
关键词 Asphalt VOCs Volatile organic compounds Green asphalt materials Reduction efficiency Hazardous emission
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Volatile Organic Compounds (VOCs) in China: Progress and Prospects of Research on Treatment Technologies and Policy Provisions
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作者 Lixia Wu Yu Zhu +2 位作者 Jing Yuan Xiaozhong Guo Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第9期1-43,共43页
Volatile organic compounds (VOCs) are an atmospheric pollutant with a boiling point of 50˚C - 260˚C at room temperature and pressure. They are precursors of sulfur dioxide and ozone, which can seriously pollute the at... Volatile organic compounds (VOCs) are an atmospheric pollutant with a boiling point of 50˚C - 260˚C at room temperature and pressure. They are precursors of sulfur dioxide and ozone, which can seriously pollute the atmosphere and endanger human health. After the “14th Five-Year Plan”, VOCs, instead of SO2, became one of the five indicators of China’s atmospheric governance. As a result, the government’s efforts to control VOCs have increased significantly. VOCs governance mustn’t be delayed. This paper provides a comprehensive summary and analysis of VOCs governance, covering the classification of VOCs, analysis of VOC governance technology (with a focus on end-of-pipe governance technology), national policy regulations, current governance shortcomings, and a forward-looking perspective on the future direction of VOCs governance, emphasizing healthy and sustainable development. 展开更多
关键词 Volatile organic compounds VOCS End-of-Pipe Treatment Technology Policy Regulations
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Comparative Analysis of Organic and Compound Fertilizers on the Yield and Metabolites of Platostoma palustre
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作者 Suhua Huang Hao Chen +7 位作者 Fan Wei Changqian Quan Meihua Xu Zhining Chen Jingchun Li Hongyu Li Lijun Shi Danfeng Tang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第10期2645-2662,共18页
To explore the effect of fertilizers on the yield and quality of Platostoma palustre,in this study,P.palustre was utilized as the research material,and field experiments were conducted with different application rates... To explore the effect of fertilizers on the yield and quality of Platostoma palustre,in this study,P.palustre was utilized as the research material,and field experiments were conducted with different application rates of compound fertilizer and organic fertilizer and non-targeted metabolomics analysis was further employed to compare and analyze the differences in the metabolic components between the compound fertilizer and organic fertilizer treatments.The results of field experiments demonstrated that both compound and organic fertilizers could promote the fresh weight,shade dry weight,and dry weight of P.palustre,with 450 kg hm−2 compound fertilizer and 4500 kg hm−2 organic fertilizer presenting the optimum effects.Non-targeted metabolomics revealed that 1096 metabolites were identified in 450 kg hm−2 compound fertilizer and 4500 kg hm−2 organic fertilizer,and 885 metabolites were annotated in the Human Metabolome Database(HMDB).There were 318 differential metabolites(DMs)found between the two treatments,and 263 metabolites were annotated in HMDB.The abundance of 2 phenolic compounds and 12 organic oxygen compounds in the treatment of 4500 kg hm−2 organic fertilizer was significantly higher than that of the 450 kg hm−2 compound fertilizer,while the abundance of 21 organic oxygen compounds,14 flavonoids,3 phenolic compounds,and 5 cinnamic acids and their derivatives was significantly up-regulated in 450 kg hm−2 compound fertilizer treatment.In addition,5 metabolic pathways were significantly enriched,and the flavone and flavonol biosynthesis was the most significantly differential metabolic pathway.These results suggested that the application of both compound fertilizers and organic fertilizers can increase the yield of P.palustre,but their effects on metabolites were different.This study has considerable implications for the planting and cultivation of P.palustre,furnishing a scientific foundation for an efficient and rational application of fertilizer. 展开更多
关键词 compound fertilizer METABOLITES organic fertilizer Platostoma palustre YIELD
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Advanced Technologies for Volatile Organic Compound (VOC) Emission Treatment: An Overview
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作者 Yizhe Li 《Journal of Electronic Research and Application》 2024年第2期1-6,共6页
This paper presents a comprehensive overview of various advanced technologies employed in the treatment of volatile organic compounds(VOCs),which are crucial pollutants in industrial emissions.The study explores diffe... This paper presents a comprehensive overview of various advanced technologies employed in the treatment of volatile organic compounds(VOCs),which are crucial pollutants in industrial emissions.The study explores different methods,including direct combustion,thermal combustion,catalytic combustion,low-temperature plasma purification,photocatalytic purification,membrane separation,and adsorption methods.Each technology is critically analyzed for its operational principles,efficiency,and applicability under different conditions.Special attention is given to adsorption concentration and catalytic combustion parallel method,highlighting its efficiency in treating low-concentration,high-volume VOC emissions.The paper also delves into the advantages and limitations of each method,providing insights into their effectiveness in various industrial scenarios.The study aims to offer a detailed guide for selecting appropriate VOC treatment technologies,contributing to enhanced environmental protection and sustainable industrial practices. 展开更多
关键词 Volatile organic compounds(VOCs) Emission treatment technologies Catalytic combustion Adsorption methods Environmental protection
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Deciphering the Origin of Abiotic Organic Compounds on Earth:Review and Future Prospects 被引量:1
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作者 WANG Chao TAO Renbiao +3 位作者 Jesse B.WALTERS REN Tianshi NAN Jingbo ZHANG Lifei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期288-308,共21页
The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance,by chemosynthetic biological communities,and for energy r... The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance,by chemosynthetic biological communities,and for energy resources.Extensive analysis of methane(CH_(4))and other organics in diverse geologic settings,combined with thermodynamic modelings and laboratory simulations,have yielded insights into the distribution of specific abiotic organic molecules on Earth and the favorable conditions and pathways under which they form.This updated and comprehensive review summarizes published results of petrological,thermodynamic,and experimental investigations of possible pathways for the formation of particular species of abiotic simple hydrocarbon molecules such as CH_(4),and of complex hydrocarbon systems,e.g.,long-chain hydrocarbons and even solid carbonaceous matters,in various geologic processes,distinguished into three classes:(1)pre-to early planetary processes;(2)mantle and magmatic processes;and(3)the gas/water-rock reaction processes in low-pressure ultramafic rock and high-pressure subduction zone systems.We not only emphasize how organics are abiotically synthesized but also explore the role or changes of organics in evolutionary geological environments after synthesis,such as phase transitions or organic-mineral interactions.Correspondingly,there is an urgent need to explore the diversity of abiotic organic compounds prevailing on Earth. 展开更多
关键词 abiotic hydrocarbons high P-T METHANE abiotic solid organic compounds deep carbon cycle
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Exhaled volatile organic compounds for diagnosis and monitoring of asthma 被引量:1
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作者 Luisa Savito Simone Scarlata +3 位作者 Andras Bikov Pierluigi Carratù Giovanna Elisiana Carpagnano Silvano Dragonieri 《World Journal of Clinical Cases》 SCIE 2023年第21期4996-5013,共18页
The asthmatic inflammatory process results in the generation of volatile organic compounds(VOCs),which are subsequently secreted by the airways.The study of these elements through gas chromatography-mass spectrometry(... The asthmatic inflammatory process results in the generation of volatile organic compounds(VOCs),which are subsequently secreted by the airways.The study of these elements through gas chromatography-mass spectrometry(GC-MS),which can identify individual molecules with a discriminatory capacity of over 85%,and electronic-Nose(e-NOSE),which is able to perform a quick onboard pattern-recognition analysis of VOCs,has allowed new prospects for non-invasive analysis of the disease in an"omics"approach.In this review,we aim to collect and compare the progress made in VOCs analysis using the two methods and their instrumental characteristics.Studies have described the potential of GC-MS and e-NOSE in a multitude of relevant aspects of the disease in both children and adults,as well as differential diagnosis between asthma and other conditions such as wheezing,cystic fibrosis,COPD,allergic rhinitis and last but not least,the accuracy of these methods compared to other diagnostic tools such as lung function,FeNO and eosinophil count.Due to significant limitations of both methods,it is still necessary to improve and standardize techniques.Currently,e-NOSE appears to be the most promising aid in clinical practice,whereas GC-MS,as the gold standard for the structural analysis of molecules,remains an essential tool in terms of research for further studies on the pathophysiologic pathways of the asthmatic inflammatory process.In conclusion,the study of VOCs through GC-MS and e-NOSE appears to hold promise for the noninvasive diagnosis,assessment,and monitoring of asthma,as well as for further research studies on the disease. 展开更多
关键词 ASTHMA Volatile organic compounds Gas chromatography-mass spectrometry Electronic-Nose Breathomics Non-invasive diagnosis
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Effective technology for processing industrial volatile organic compounds by the atmospheric pressure microwave plasma torch
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作者 Da-Shuai Li Ling Tong 《Journal of Electronic Science and Technology》 EI CAS CSCD 2023年第2期87-94,共8页
In this study,we investigated the abatement of volatile organic compounds(VOCs)by the atmospheric pressure microwave plasma torch(AMPT).To study the treatment efficiency of AMPT,we used the toluene and water-based var... In this study,we investigated the abatement of volatile organic compounds(VOCs)by the atmospheric pressure microwave plasma torch(AMPT).To study the treatment efficiency of AMPT,we used the toluene and water-based varnish to simulate VOCs,respectively.By measuring the compounds and contents of the mixture gas before/after the microwave plasma process,we have calculated the treatment efficiency of AMPT.The experimental results show that the treatment efficiency of AMPT for toluene with a concentration of 17.32×10^(4) ppm is up to 60 g/kWh with the removal rate of 86%.For the volatile compounds of water-based varnish,the removal efficiency is up to 97.99%.We have demonstrated the higher potential for VOCs removal of the AMPT process. 展开更多
关键词 Atmospheric microwave plasma Industrial volatile organic compounds(VOCs)processing Spectroscopic diagnostic
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Adsorptive and catalytic properties in the removal of volatile organic compounds over zeolite-based materials 被引量:48
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作者 章凌 彭悦欣 +3 位作者 张娟 陈龙 孟祥举 肖丰收 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期800-809,共10页
Volatile organic compounds(VOCs) are a major component in air pollutants and pose great risks to both human health and environmental protection. Currently, VOC abatement in industrial applications is through the use... Volatile organic compounds(VOCs) are a major component in air pollutants and pose great risks to both human health and environmental protection. Currently, VOC abatement in industrial applications is through the use of activated carbons as adsorbents and oxide-supported metals as catalysts. Notably, activated carbons easily adsorb water, which strongly hinders the adsorption of VOCs; conventional oxides typically possess relatively low surface areas and random pores, which effectively influence the catalytic conversion of VOCs. Zeolites, in contrast with activated carbons and oxides, can be designed to have very uniform and controllable micropores, in addition to tailored wettability properties, which can favor the selective adsorption of VOCs. In particular, zeolites with selective adsorptive properties when combined with catalytically active metals result in zeolite-supported metals exhibiting significantly improved performance in the catalytic combustion of VOCs compared with conventional oxide-supported catalysts. In this review, recent developments on VOC abatement by adsorptive and catalytic techniques over zeolite-based materials have been briefly summarized. 展开更多
关键词 Air pollution Volatile organic compound ZEOLITE Supported catalyst Catalytic combustion
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Catalytic removal of volatile organic compounds using ordered porous transition metal oxide and supported noble metal catalysts 被引量:27
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作者 刘雨溪 邓积光 +2 位作者 谢少华 王治伟 戴洪兴 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1193-1205,共13页
Most of volatile organic compounds (VOCs) are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalys... Most of volatile organic compounds (VOCs) are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalysts. Many catalysts including transition metal oxides, mixed metal oxides, and sup‐ported noble metals have been developed. Among these catalysts, the porous ones attract much attention. In this review, we focus on recent advances in the synthesis of ordered mesoporous and macroporous transition metal oxides, perovskites, and supported noble metal catalysts and their catalytic oxidation of VOCs. The porous catalysts outperformed their bulk counterparts. This excel‐lent catalytic performance was due to their high surface areas, high concentration of adsorbed oxy‐gen species, low temperature reducibility, strong interaction between noble metal and support and highly dispersed noble metal nanoparticles and unique porous structures. Catalytic oxidation of carbon monoxide over typical catalysts was also discussed. We made conclusive remarks and pro‐posed future work for the removal of VOCs. 展开更多
关键词 Volatile organic compound Catalytic combustion Porous transition metal oxide Perovskite-type oxide Supported noble metal catalyst
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Negative effects of dissolved organic compounds on settling performance of goethite in Bayer red mud 被引量:5
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作者 王梦 胡慧萍 刘锦伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期429-439,共11页
Goethite, a typical iron-containing monomineral in red mud, was synthesized under the simulated Bayer digestion condition during the alumina production. The effects of dissolved organic compounds including sodium ... Goethite, a typical iron-containing monomineral in red mud, was synthesized under the simulated Bayer digestion condition during the alumina production. The effects of dissolved organic compounds including sodium formate, sodium acetate, sodium oxalate, sodium salicylate and disodium phthalate on the settling performance of goethite slurries were studied. The settling performance of the slurries was also investigated with the addition of self-made hydroxamated polyacrylamide flocculant (HCPAM). The adsorption mechanism of dissolved organic compounds on the goethite surfaces was studied by FT-IR and XPS, respectively. The results show that the addition of organic compounds lowers the settling performance of the slurries and a deterioration in settling performance is observed in the order of sodium oxalate 〉 sodium salicylate (~ disodium phthalate) 〉 sodium formate 〉 sodium acetate. Moreover, HCPAM can efficiently eliminate the negative effects of sodium formate, sodium acetate and sodium oxalate on the settling performance of the goethite slurries, but it can only partially improve the settling performance of the goethite slurries containing sodium salicylate or disodium phthalate. FT-IR and XPS results show that these organic compounds are chemically adsorbed on the goethite surface. 展开更多
关键词 GOETHITE dissolved organic compound settling performance adsorption mechanism
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QSPR Study on the Boiling Points of Some Oxygenand Sulfur-containing Organic Compounds 被引量:1
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作者 陈建挺 刘红玲 +2 位作者 王甫洋 于红霞 李定龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1561-1568,共8页
Structural and thermodynamic parameters of 56 oxygen-containing and 56 sulfur- containing organic compounds were computed at the B3LPY/6-311G** level using density functional theory (DFT) method. Furthermore,the d... Structural and thermodynamic parameters of 56 oxygen-containing and 56 sulfur- containing organic compounds were computed at the B3LPY/6-311G** level using density functional theory (DFT) method. Furthermore,the dependent equations between the experimental data of boiling points (Tb) and theoretical parameters were proposed with SPSS12.0 for windows software,whose correlation coefficients R2 are 0.933 and 0.945. These dependent equations were validated by cross-validation method (q2 are 0.923 and 0.929,respectively). VIF (variance inflation factors) and t-value methods were also used to verify the significance and self-correlationship of each variable. Results indicate that our dependent equation exhibits good prediction ability,and molecular polarizability (α) is the main factor affecting the Tb of oxygen- and sulfur-containing organic compounds. To our interest,obvious dependence could also be found among the oxygen- and sulfur-containing organic compounds' experimental data of boiling points (Tb) with R^2 of 0.857. 展开更多
关键词 boiling points oxygen-containing organic compounds sulfur-containing organic compounds quantitative structure-property relationship (QSPR) DFT
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Stability of sedimentary organic matter: Insights from molecular and redox analyses
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作者 Qi Li Chao Zhang Baoqing Shan 《Environmental Science and Ecotechnology》 SCIE 2024年第6期266-275,共10页
Sedimentary organic matter(SOM)affects the stability of the aquatic carbon pool.The degradation process of SOM is complex for its multifaceted composition.The concentration and properties of SOM affect its steady stat... Sedimentary organic matter(SOM)affects the stability of the aquatic carbon pool.The degradation process of SOM is complex for its multifaceted composition.The concentration and properties of SOM affect its steady state,yet the transformation processes of SOM in lakes remain unclear.Here we show the molecular and redox perspectives of SOM stability in polluted sediments with high organic matter content and diverse vegetation.We find significant differences in carbon fractions across various sites.The origin of the organic matter,determined using excitation-emission matrix spectra,influences the consistency of organic matter composition and biochemical degradation in lacustrine sediment.We also observe that sulfur-containing substances decrease carbon chain length and reduce organic matter stability.Fourier-transform ion cyclotron resonance mass spectrometry shows that sulfur-containing substances decrease the degree of saturation and cause reduction.In contrast,nitrogen-containing compounds increase the modified aromaticity index and humin content,enhancing organic carbon complexity and stability(p<0.05).These results complement the characteristics and transformations of SOM.In a broader perspective,this study contributes to laying the foundation for understanding SOM stability in the carbon cycle and its future effects. 展开更多
关键词 Carbon stability Redox state FT-ICR MS Sedimentary organic matter Nitrogen-and sulfur-containing compounds
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STUDY ON DEGRADATION OF LDPE CATALYZED BY MULTI-VALENCE METALLIC ORGANIC COMPOUNDS AT COMPOST TEMPERATURE
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作者 于九皋 陈崧哲 《Transactions of Tianjin University》 EI CAS 2001年第4期290-293,共4页
The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost... The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost environment.The mechanical properties,viscosity average molecular weight (M η) of PE and hydroperoxide (POOH) concentration in the samples were measured.FT IR and DSC were also applied to characterize some samples.It was shown that the above mentioned metallic organic compounds can catalyze the degradation of LDPE efficiently.After 2 months aging,all samples with catalysts became fragile and the M η of the material decreased dramatically.Furthermore,the concentration of carbonyl and the degree of crystallinity of the material increased with the aging time. 展开更多
关键词 polyethylene multi valence metallic organic compound COMPOST DEGRADATION HYDROPEROXIDE
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Characterization and Source Apportionment of Volatile Organic Compounds in Urban and Suburban Tianjin, China 被引量:19
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作者 HAN Meng LU Xueqiang +2 位作者 ZHAO Chunsheng RAN Liang HAN Suqin 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第3期439-444,共6页
Tianjin is the third largest megacity and the fastest growth area in China,and consequently faces the problems of surface ozone and haze episodes.This study measures and characterizes volatile organic compounds (VOCs... Tianjin is the third largest megacity and the fastest growth area in China,and consequently faces the problems of surface ozone and haze episodes.This study measures and characterizes volatile organic compounds (VOCs),which are ozone precursors,to identify their possible sources and evaluate their contribution to ozone formation in urban and suburban Tianjin,China during the HaChi (Haze in China) summer campaign in 2009.A total of 107 species of ambient VOCs were detected,and the average concentrations of VOCs at urban and suburban sites were 92 and 174 ppbv,respectively.Of those,51 species of VOCs were extracted to analyze the possible VOC sources using positive matrix factorization.The identified sources of VOCs were significantly related to vehicular activities,which specifically contributed 60% to urban and 42% to suburban VOCs loadings in Tianjin.Industrial emission was the second most prominent source of ambient VOCs in both urban and suburban areas,although the contribution of industry in the suburban area (36%) was much higher than that at the urban area (16%).We conclude that controlling vehicle emissions should be a top priority for VOC reduction,and that fast industrialization and urbanization causes air pollution to be more complex due to the combined emission of VOCs from industry and daily life,especially in suburban areas. 展开更多
关键词 volatile organic compounds source apportionment positive matrix factorization OZONE MEGACITY
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Measurement of in-vehicle volatile organic compounds under static conditions 被引量:28
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作者 YOU Ke-wei GE Yun-shan +4 位作者 HU Bin NING Zhan-wu ZHAO Shou-tang ZHANG Yan-ni XIE Peng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第10期1208-1213,共6页
The types and quantities of volatile organic compounds (VOCs) inside vehicles have been determined in one new vehicle and two old vehicles under static conditions using the Thermodesorber-Gas Chromatograph/Mass Spec... The types and quantities of volatile organic compounds (VOCs) inside vehicles have been determined in one new vehicle and two old vehicles under static conditions using the Thermodesorber-Gas Chromatograph/Mass Spectrometer (TD-GC/MS). Air sampling and analysis was conducted under the requirement of USEPA Method TO-17. A room-size, environment test chamber was utilized to provide stable and accurate control of the required environmental conditions (temperature, humidity, horizontal and vertical airflow velocity, and background VOCs concentration). Static vehicle testing demonstrated that although the amount of total volatile organic compounds (TVOC) detected within each vehicle was relatively distinct (4940 μg/m^3 in the new vehicle A, 1240 μg/m^3 in used vehicle B, and 132 μg/m^3 in used vehicle C), toluene, xylene, some aromatic compounds, and various C7-C12 alkanes were among the predominant VOC species in all three vehicles tested. In addition, tetramethyl succinonitrile, possibly derived from foam cushions was detected in vehicle B. The types and quantities of VOCs varied considerably according to various kinds of factors, such as, vehicle age, vehicle model, temperature, air exchange rate, and environment airflow velocity. For example, if the airflow velocity increases from 0.1 m/s to 0.7 m/s, the vehicle's air exchange rate increases from 0.15 h^-1 to 0.67 h^-1, and in-vehicle TVOC concentration decreases from 1780 to 1201 μg/m^3. 展开更多
关键词 volatile organic compounds (VOCs) in-vehicle trim material static conditions
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