Influence of Reactive Volatile Organic Compounds on Ozone Production in Houston-Galveston-Brazoria Area

Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-attainment area for ozone (O3). A summer episode of May 28 to July 2, 2006 is simulated using Comprehensive Air Quality Model with extensions (CAMx). During this period O3 concentration in HGB often exceeds the National Ambient Air Quality Standards (NAAQS) 0.075 ppm of average 8 hour O3 concentration. HGB area has numerous point sources. Various studies found that some specific volatile organic compounds are very reactive in atmosphere. The objective of this study is to analyze the influence of volatile organic compounds present in point source emissions on the air quality of HGB area. For this purpose ozone sensitivity for HGB area is analyzed by the ratio of hydrogen peroxides (H2O2) to nitric acid (HNO3). HGB area is found NOx limited but reactive VOCs are found to be influential too. From (1-4 June, 2006) maximum O3 concentration was found on weekend, June 3. VOCs such as Acetaldehyde (ALD2), Formaldehyde (FORM) and Alkane (ETHA) showed good correlation with O3 concentrations on that day. In addition, Peroxyacetyl nitrate (PAN) formation was found correlated to higher ozone production. Criteria pollutant Sulfur dioxide (SO2) was found to influence the ALD2 and ETHA concentrations, and thus indirectly influenced O3 production.

Modern approaches for detection of volatile organic compounds in metabolic studies focusing on pathogenic bacteria:Current state of the art

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.

Analysis of Micro Organic Compound Pollution in Major City River Reaches of the Main Stem of the Changjiang River

It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was performed on micro organic compounds in the water, bottom material and fish bodies which were sampled from major city river reaches of the Changjiang River. Based on the test result, researchers described and analyzed the sorts, concentration level and distribution features of micro organic compounds. A comprehensive evaluation was conducted by adopting the method of MEG (Multimedia Environmental Goals). The study indicated that ① the water body of major city river reaches of the Changjiang River has been generally polluted. In the test, totally 12 types with 308 kinds of organic compounds were detected. The main pollutants were paraffins, PAHs and lipids; and ② micro organic pollutant content in fish bodies was generally higher than that in bottom material which is in turn higher than that in water; and ③ pollution is relatively severe in the river reaches of mid-to-large comprehensive industrial cities with fairly great TAS (Total Ambient Severity) of public health and ecological system.

Comparative Analysis of Organic and Compound Fertilizers on the Yield and Metabolites of Platostoma palustre

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.

Identification of breath volatile organic compounds to distinguish pancreatic adenocarcinoma,pancreatic cystic neoplasm,and patients without pancreatic lesions

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.

Towards green asphalt materials with lower emission of volatile organic compounds: A review on the release characteristics and its emission reduction additives

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.

Mass-Spectrometric Method of Measurement of Isotopic Content of Nitrogen in Organic Compounds

Nitrogen-15 isotope-modified compounds are widely used in medicine, pharmacology, agriculture and various fields of science and their nomenclature is gradually increasing. Their widespread use depends on the availability of inexpensive and simple isotope analysis methods. The present article is an attempt to determine the nitrogen-15 isotope content directly in organic compounds without their conversion. The general principle of possibility of determination of the isotopes of nitrogen directly in organic compounds is proposed. Based on the study of mass-spectra of Carbamide Carbonyldiamide, isocyanic acid and nitrobenzene the mass peaks are selected, by which it is possible to determine the atomic fraction of the isotopes of nitrogen. The respective formulas are proposed.

Advanced Technologies for Volatile Organic Compound (VOC) Emission Treatment: An Overview

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.

Organic Compounds Possessing the Plastic Crystalline Phase: Calculation of Their Fusion Enthalpies

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.

Volatile Organic Compounds (VOCs) in China: Progress and Prospects of Research on Treatment Technologies and Policy Provisions

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.

Concentration control of volatile organic compounds by ionic liquid absorption and desorption

Volatile organic compounds(VOCs)are difficult to be eliminated safely and effectively because of their large concentration fluctuations.Thus,maintaining a stable concentration of VOCs is a significant study.In this research,H2O,Tween-80,[Emim]BF4,[Emim]PF6,and[Hnmp]HSO4 were applied to absorb and desorb simulated VOCs.The ionic liquid[Emim]BF4 demonstrated the best performance and was thus selected for further experiments.As the ionic liquid acted as a buffer,the toluene concentration with a fluctuation of 2000–20000 mg·m-3 was stabilized at 6000–12000 mg·m-3.Heating distillation(90°C)was highly efficient to recover[Emim]BF4 from toluene.The regenerated[Emim]BF4 could retain its initial absorption capacity even after multiple cycles.Moreover,[Emim]BF4 had the same buffer function on various aromatic hydrocarbons.

Volatile Organic Compound Emissions from Surface Coating Facilities: Characterization of Facilities, Estimation of Emission Rates, and Dispersion Modeling of Off-Site Impacts

Surface coating facilities are major sources of volatile organic compounds (VOCs) in urban areas. These VOCs can contribute to ground-level ozone formation, and many are hazardous air pollutants (HAPs), including xylene, ethylbenzene, and toluene. This project was conducted in order to provide information for updating the Texas Commission on Environmental Quality (TCEQ), USA, permit by rule for Surface Coating Facilities. Project objectives were: 1) To develop a database of information regarding surface coating facilities in Texas;2) To estimate maximum emission rates for various VOC species from surface coating facilities in Texas;3) To conduct dispersion modeling to estimate off-site impacts from surface coating facilities. The database was developed using 286 TCEQ permit files authorizing surface coating facilities in Texas during 2006 and 2007. The database was designed to include information important for estimating emission rates, and for using as inputs to the dispersion model. Hourly and annual emissions of volatile organic compounds (VOCs), particulate matter (PM), and exempt solvents (ES) were calculated for each permitted entity/ company in the database, according to equations given by TCEQ. Dispersion modeling was then conducted for 3 facility configurations (worst-case stack height, good practice stack height, and fugitive emissions), for urban and rural dispersion parameters, for 8-hour and 24-hour operating scenarios, and for 1-hour, 24-hour, and annual averaging times, for a total of 36 scenarios. The highest modeled concentrations were for the worst-case stack height, rural dispersion parameters, 24-hour operation scenario, and 1-hour averaging time. 108 specific chemical species, which are components of surface coatings, were identified as candidates for further health impacts review.

Composite bilayer films with organic compound-triggered bending properties

Organic compounds are widely used in both industry and daily life,and composite bilayer films with organic compound-triggered bending properties are promising for applications of transducers,soft robotics,and so on.Here,a universal and straightforward strategy to generate composite bilayer films with organic compoundtriggered bending properties is demonstrated.The composite bilayer films with organic compound-triggered bending properties are designed with bilayer structures,in which one layer is a porous polymeric membrane with appropriate solubility parameter that matches the value of organic solvents in order to produce prominent affinity to the solvent molecules,and the other layer is reduced graphene oxide membrane stacked on the porous polymeric membrane as an inert layer for restraining the swelling of the polymeric membrane on one side.Guided by matching the solubility parameters between solvent and polymer,a significant bending curvature of 27.3 cm-1 is obtained in acetone vapor.The results in this study will provide valuable guidance for designing and developing functional composite materials with significant organic compound-triggered bending properties.

Exhaled volatile organic compounds for diagnosis and monitoring of asthma

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.

Compositional Characterization of Nitrogen Compounds in Changqing Crude Oil and Its Heavy Distillates

The nitrogen-containing compounds in Changqing crude oil, its atmospheric residue(AR), and vacuum reside(VR) were characterized by negative and positive ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). The heteroatom compounds(N_1, N_2, N_1O_1, O_1, and O_2 class species) could be identified by the negative ESI analysis, while the positive mode could only detect the N_1, N_2, and N_1O_1 class species. Among them, the N_1 class species were found to be predominant in crude oil, as confirmed by either negative or positive ESI analyses,which were similar in composition to AR and VR. These compounds with higher abundance were characterized by double bond equivalent(DBE) values and carbon numbers. The composition of these compounds in crude oil and its AR as well as VR was correlated with their different boiling range, DBE values and carbon numbers. The negative ESI analysis showed that the abundant N_1 class species in crude oil and AR were centered at a DBE value of 12, and these species were likely benzocarbazoles, while the N_1 class species with the DBE value ranging from 13 to 16 having more complicated molecular structures were dominant in VR. And the positive ESI analysis gave the information of the abundant N_1 class species in crude oil, AR, and VR having the DBE values in the range of 10, 9―11, and 10―16, respectively, which were likely the compounds with the core of quinoline and benzoquinoline. The analysis confirmed that the distillation process in refinery preferentially removed the low DBE value and low molecular N-class species and brought them into the light and medium distillates, while those N-class species having a high molecular condensation in the molecules with large carbon number remained in the residual oil and could continually affect the downstream oil refining process.

Deciphering the Origin of Abiotic Organic Compounds on Earth:Review and Future Prospects

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.

Diagnosing gastrointestinal illnesses using fecal headspacevolatile organic compounds

Volatile organic compounds(VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool.

Greenhouses Gases, Carbonyls, and Volatile Organic Compounds Surface Flux Emissions at Three Final Waste Disposal Sites Located in the Metropolitan Area of Costa Rica

The surface flux emissions for volatile organic compounds (VOC’s) (alcohols and aromatic species), priority carbonyls and greenhouse gases, were measured in three different final disposal sites for urban solid waste located in the metropolitan area of Costa Rica, between July and October 2014. The emissions fluxes were determined using the static sampling chamber technique coupled to two different adsorption tubes: active charcoal (Supelco, ORBO 32) to capture BTEX and alcohols;and 2,4-DNPH coated silica gel (SKC, 226-119) for carbonyls. As for the VOCs, the BTEX, Alcohols, and Carbonyls total fluxes were in the range of 3 to 258, 1 to 318 and 0.4 to 8.5 mg/(m2d&#237a), respectively. The magnitudes per site were in the following order La Carpio > El Huaso > Rio Azul. Ethanol and BTEX presented a high correlation in all the cases because possibly they are sharing the same sources or formation mechanisms. The emission fluxes spatial distributions among the sites were very variable and dependent on the location of the active cells and their age. Only La Carpio showed a more homogeneous distribution due to its middle age.

Pollution of organic compounds and heavy metals in a coal gangue dump of the Gequan Coal Mine, China

Samples around a coal gangue dump of the Gequan Coal Mine were collected in April 2009. GC (gas chromatography) and GC/MS (gas chromatography/mass spectrometry) were employed to analyze the composition of organic matter in the samples. ICP-MS (inductively coupled plasma mass spectrometry) was used to determine the concentrations of heavy metals. The contents of organic extracts are within the range of 140-750 mg/kg. Alkand aro-ratios are relatively high. Compared to those of the background sample (GQ13 ), the contents of saturated hydrocarbon compounds in all the samples are relatively high. The contents of polycyclic aromatic hydrocarbons (PAHs) are relatively high with the distance getting closer to the coal gangue dump. These indicate that organic matter in the samples is from coal particles of the coal gangue dump. The distributions of heavy metals are very similar: the contents decrease with distance from the dump, which indicates that the harmful heavy metals from the coal gangue dump have polluted as thick as at least 500 m.

Source,Process and End Treatment Technology of Volatile Organic Compounds in Oil Storage

Oil storage is a source of volatile organic compounds( VOCs). Volatile organic compounds can cause different damages to the environment,animals and plants. Therefore, it is important to control the discharge of VOCs in oil storage. In this paper,the control technology of sources of VOCs pollution in oil storage was analyzed from the source,process and end treatment,and measures for the prevention and control of VOCs pollution in oil storage were proposed.