scholarly journals Temperature and acidity dependence of secondary organic aerosol formation from <i>α</i>-pinene ozonolysis with a compact chamber system

2021 ◽  
Vol 21 (8) ◽  
pp. 5983-6003
Author(s):  
Yange Deng ◽  
Satoshi Inomata ◽  
Kei Sato ◽  
Sathiyamurthi Ramasamy ◽  
Yu Morino ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Chemical Compounds ◽  
Negative Temperature ◽  
Heterogeneous Reactions ◽  
Chemical Components ◽  
Seed Particle ◽  
Aerosol Formation ◽  
Seed Particles ◽  
Wide Range ◽  
Acid Catalyzed

Abstract. Secondary organic aerosols (SOAs) affect human health and climate change prediction; however, the factors (e.g., temperature, acidity of pre-existing particles, and oxidants) influencing their formation are not sufficiently resolved. Using a compact chamber, the temperature and acidity dependence of SOA yields and chemical components in SOA from α-pinene ozonolysis were systematically investigated under 278, 288, and 298 K temperatures using neutral ((NH4)2SO4) and acidic (H2SO4+((NH4)2SO4)) seed aerosols. SOA components with m/z less than 400 were analyzed using negative electrospray ionization liquid-chromatography time-of-flight mass spectrometry. Based on the slightly negative temperature dependence of the SOA yields, the enthalpies of vaporization under neutral and acidic seed conditions were estimated to be 25 and 44 kJ mol−1, respectively. In addition, SOA yields increased with an increase in the acidity of seed particles (solid/near-solid state) at low SOA mass loadings, when compared with the seed particle amounts. Acidity dependence analysis of the chemical formula, molecular mass, and O:C ratio of the detected compounds indicated the enhanced formation of multiple oligomers in the wide molecular mass range with a wide range of O:C ratios under acidic seed conditions. The peak abundances of some chemical compounds increased with an increase in the acidity of seed particles (e.g., m/z  197, 311, 313, 339, 355, and 383), while decreases in the peak abundances of some chemical compounds were observed (e.g., m/z 171, 185, 215, 343, and 357). The acidity dependence could be explained by acid-catalyzed heterogeneous reactions or acid-catalyzed decomposition of hydroperoxides. In addition, organosulfate (OS) formation was observed under acidic seed conditions. Six out of the 11 detected OSs were potentially formed via the aldehyde + HSO4- pathway.

scholarly journals Temperature and acidity dependence of secondary organic aerosol formation from α-pinene ozonolysis with a compact chamber system

2020 ◽  
Author(s):  
Yange Deng ◽  
Satoshi Inomata ◽  
Kei Sato ◽  
Sathiyamurthi Ramasamy ◽  
Yu Morino ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Secondary Organic Aerosol ◽  
Negative Temperature ◽  
Organic Aerosol ◽  
Heterogeneous Reactions ◽  
Chemical Components ◽  
Seed Particle ◽  
Aerosol Formation ◽  
Wide Range ◽  
Acid Catalyzed

Abstract. Secondary organic aerosol (SOA) is of great importance, affecting human health and the prediction of climate change; however, the factors (e.g., temperature, acidity of pre-existing particles, and oxidants) influencing its formation are not sufficiently resolved. In this study, a compact Teflon atmospheric simulation chamber is developed, in which reactions in atmospheric pressure conditions can be performed with controlled temperature, humidity, oxidation agents, and seed particle acidity. Using the chamber, α-pinene ozonolysis SOA formation was simulated under temperatures of 278 K, 288 K, and 298 K with neutral/acidic seed aerosols. The SOA components of m / z less than 400 were analyzed using negative electrospray ionization liquid-chromatography time-of-flight mass spectrometry. The temperature and acidity dependence of SOA yields and chemical components were investigated. From the slightly negative temperature dependence of the SOA yields, the enthalpy of vaporization in neutral and acidic seed conditions was estimated to be 25 and 44 kJ mol−1, respectively. With these values, the volatility distributions of the identified SOA compounds were consistently explained. Acidity dependence analysis of the chemical formula, molecular mass, and O : C ratio of the detected compounds indicated the enhanced formation of many oligomers in the wide molecular mass range with a wide range of O : C ratios under acidic seed conditions. The acidity dependence of certain major compounds could be explained by acid-catalyzed heterogeneous reactions (e.g., m / z 171, 185, 343, and 357) or acid-catalyzed decomposition of hydroperoxides (e.g., m / z 215 and 197). In addition, the formation of organosulfates (OS) was observed under acidic seed conditions. We proposed that six of the eleven detected OS were possibly formed through the aldehyde + HSO4− pathway. Further studies on the OS formation during α-pinene ozonolysis are warranted.

Therapeutic Properties of Several Chemical Compounds from Salvia officinalis L. in Alzheimer’s Disease

2020 ◽  
Vol 21 ◽  
Author(s):  
Georgiana Uță ◽  
Denisa Ștefania Manolescu ◽  
Speranța Avram
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Side Effects ◽  
Chemical Compounds ◽  
Natural Compounds ◽  
Salvia Officinalis ◽  
Chemical Structures ◽  
In Silico Studies ◽  
Wide Range ◽  
Salvia Officinalis L

Background.: Currently, the pharmacological management in Alzheimer's disease is based on several chemical structures, represented by acetylcholinesterase and N-methyl-D-aspartate (NMDA) receptor ligands, with still unclear molecular mechanisms, but severe side effects. For this reason, a challenge for Alzheimer's disease treatment remains to identify new drugs with reduced side effects. Recently, the natural compounds, in particular certain chemical compounds identified in the essential oil of peppermint, sage, grapes, sea buckthorn, have increased interest as possible therapeutics. Objectives.: In this paper, we have summarized data from the recent literature, on several chemical compounds extracted from Salvia officinalis L., with therapeutic potential in Alzheimer's disease. Methods.: In addition to the wide range of experimental methods performed in vivo and in vitro, also we presented some in silico studies of medicinal compounds. Results. Through this mini-review, we present the latest information regarding the therapeutic characteristics of natural compounds isolated from Salvia officinalis L. in Alzheimer's disease. Conclusion.: Thus, based on the information presented, we can say that phytotherapy is a reliable therapeutic method in a neurodegenerative disease.

Phytochemistry and Pharmacology of the Genus Pedicularis Used in Traditional Chinese Medicine

2014 ◽  
Vol 42 (05) ◽  
pp. 1071-1098 ◽  
Author(s):  
Mao-Xing Li ◽  
Xi-Rui He ◽  
Rui Tao ◽  
Xinyuan Cao
Keyword(s):  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Chemical Constituents ◽  
Iridoid Glycosides ◽  
In Vivo Studies ◽  
Chemical Components ◽  
Wide Range ◽  
Phenylpropanoid Glycosides

In the present review, the literature data on the chemical constituents and biological investigations of the genus Pedicularis are summarized. Some species of Pedicularis have been widely applied in traditional Chinese medicine. A wide range of chemical components including iridoid glycosides, phenylpropanoid glycosides (PhGs), lignans glycosides, flavonoids, alkaloids and other compounds have been isolated and identified from the genus Pedicularis. In vitro and in vivo studies indicated some monomer compounds and extracts from the genus Pedicularis have been found to possess antitumor, hepatoprotective, anti-oxidative, antihaemolysis, antibacterial activity, fatigue relief of skeletal muscle, nootropic effect and other activities.

Determination of Bioactive Components of 60°С Volatiles from Cinnamomum camphora Branches by TD-GC/MS

2011 ◽  
Vol 230-232 ◽  
pp. 852-856
Author(s):  
Qing Li ◽  
Dang Quan Zhang ◽  
Qi Mei Liu ◽  
Kuan Peng
Keyword(s):  
Chemical Compounds ◽  
Chemical Components ◽  
Cinnamomum Camphora ◽  
Bioactive Components ◽  
Industrial Materials ◽  
Analytical Result ◽  
Main Components

The chemical components of helium volatiles from the fresh branches of Cinnamomum camphora were studied by TD-GC/MS. The analytical result by 60°С-based TD-GC/MS showed that 55 peaks were obtained from the helium volatiles from the fresh branches of Cinnamomum camphora and 53 chemical compounds were identified. The results showed that the main components were as: Bicyclo[2.2.1]heptan-2-one, 1,7,7-trimethyl-, (1R)- (15.4328%), 1,3-Benzodioxole, 5-(2-propenyl)- (14.881%), Tricyclo[2.2.1.0(2,6)]heptane, 1,7-dimethyl-7-(4-methyl-3-pentenyl)-, (-)- (12.694%), p-menth-1-en-8-ol (9.832%), Bicyclo[2.2.1]heptane, 2-methyl-3-methylene-2-(4-methyl-3- pentenyl)-, (1S-exo)- (6.143%), 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl- (5.365%), Bicyclo[3.1.1] hept-2-ene, 2,6-dimethyl-6-(4-methyl-3-pentenyl)- (4.527%), Naphthalene, 1,2,3,5,6,8a- hexahydro-4,7-dimethyl-1-(1-methylethyl)-, (1S-cis)- (4.129%), 3-Cyclohexen-1-ol, 4-methyl-1- (1-methylethyl)- (2.965%), Borneol (2.627%), Bicyclo[2.2.1]heptan-2-ol, 1,7,7-trimethyl-, acetate, (1S-endo)- (2.586%), Copaene (2.534%), 1,6,10-Dodecatriene, 7,11-dimethyl-3-methylene-, (Z)- (1.612%), (-)-Isosativene (1.121%), etc. The analytical result suggested that the helium volatiles from the fresh branches of Cinnamomum camphora could be used as industrial materials of biomedicines and spicery.

Theoretical analysis of SWCNT- MWCNT/H2O hybrid flow over an upward/downward moving rotating disk

2021 ◽  
pp. 239779142098028
Author(s):  
R.J. Punith Gowda ◽  
R. Naveenkumar ◽  
J.K. Madhukesh ◽  
B.C. Prasannakumara ◽  
Rama Subba Reddy Gorla
Keyword(s):  
Heterogeneous Reaction ◽  
Three Dimensional ◽  
Rotating Disk ◽  
Heterogeneous Reactions ◽  
Hybrid Nanofluid ◽  
Boundary Constraints ◽  
Wide Range ◽  
Contraction Parameter ◽  
Dimensional Parameters ◽  
Source Sink

The flow-through various disk movement has wide range of applications in manufacturing processes like, computer storage equipment’s, rotating machines, electronic and various types of medical equipment’s. Inspired from these applications, here we scrutinised the consequences of homogeneous-heterogeneous reactions and uniform heat source/sink on the three-dimensional (3D) hybrid SWCNT-MWCNT’s flow on time dependent moving upward/downward rotating disk. The renowned innovation of this paper is the application of the hybrid nanofluid made up of SWCNT and MWCNT’s. Heat generation/absorption effect for the disk that does not move up or down creates a dual flow on the disk. Alternatively, the rotation and upright motion of the disk creates a 3D flow on the surface which has not been considered in the open literature. The modelled PDE’s are reduced in to ODE’s by opting suitable similarity variables and boundary constraints. Here, we used RKF-45 method to obtain the numerical approximations by adopting shooting technique. The analysis of rate of heat transfer is done through graphs. Further, change in velocity, thermal and concentration profiles for various non-dimensional parameters are deliberated briefly and illustrated with the help of suitable plots. The results reveal that, the, rise in values of homogeneous and heterogeneous reaction parameters improve the rate of reaction which results in reduction of the distribution rate and diminishes the concentration gradient. An increase in expansion/contraction parameter enhances the velocity and thermal gradients.

scholarly journals Actinomycetes as An Environmental Scrubber

2021 ◽  
Author(s):  
Sutaria Devanshi ◽  
Kamlesh R. Shah ◽  
Sudipti Arora ◽  
Sonika Saxena
Keyword(s):  
Secondary Metabolites ◽  
Agricultural Waste ◽  
Chemical Compounds ◽  
Filamentous Bacteria ◽  
Primary And Secondary Metabolites ◽  
Sustainable Environment ◽  
Potential Source ◽  
Wide Range ◽  
Bioactive Secondary Metabolites ◽  
Broad Variety

Biotechnological tools engaged in the bioremediation process are in reality, sophisticated and dynamic in character. For specialized reasons, a broad variety of such devices are employed to produce a safe and balanced environment free of all types of toxins and so make life simpler for humans on planet Earth. Actinomycetes is one of these extremely important and functionally helpful groups. They can be used for a variety of bioremediation objectives, including biotransformation, biodegradation, and many more. Actinomycetes are one of the most varied groups of filamentous bacteria, capable of prospering in a variety of ecological settings because to their bioactive capabilities. They’re famous for their metabolic diversity, which includes the synthesis of commercially useful primary and secondary metabolites. They produce a range of enzymes capable of totally destroying all of the constituents. They are well-known for their ability to produce bioactive secondary metabolites. Members of various genera of Actinomycetes show promise for application in the bioconversion of underutilized urban and agricultural waste into high-value chemical compounds. The most potential source is a wide range of important enzymes, some of which are synthesized on an industrial scale, but there are many more that have yet to be discovered. Bioremediation methods, which use naturally existing microbes to clear residues and contaminated regions of dangerous organic chemicals, are improving all the time. In the realm of biotechnological science, the potential of actinomycetes for bioremediation and the synthesis of secondary metabolites has opened up intriguing prospects for a sustainable environment.

scholarly journals Recent advances in the asymmetric phosphoric acid-catalyzed synthesis of axially chiral compounds

2021 ◽  
Vol 17 ◽  
pp. 2729-2764
Author(s):  
Alemayehu Gashaw Woldegiorgis ◽  
Xufeng Lin
Keyword(s):  
Phosphoric Acid ◽  
Asymmetric Catalysis ◽  
Medicinal Chemistry ◽  
High Efficiency ◽  
Biologically Active ◽  
Chiral Compounds ◽  
Chiral Phosphoric Acid ◽  
Wide Range ◽  
Axially Chiral ◽  
Acid Catalyzed

In recent years, the synthesis of axially chiral compounds has received considerable attention due to their extensive application as biologically active compounds in medicinal chemistry and as chiral ligands in asymmetric catalysis. Chiral phosphoric acids are recognized as efficient organocatalysts for a variety of enantioselective transformations. In this review, we summarize the recent development of chiral phosphoric acid-catalyzed synthesis of a wide range of axially chiral biaryls, heterobiaryls, vinylarenes, N-arylamines, spiranes, and allenes with high efficiency and excellent stereoselectivity.

Pedometric tools for classification of southwestern Amazonian soils: A quali-quantitative interpretation incorporating visible-near infrared spectroscopy

2022 ◽  
pp. 096703352110618
Author(s):  
Orlando CH Tavares ◽  
Tiago R Tavares ◽  
Carlos R Pinheiro Junior ◽  
Luciélio M da Silva ◽  
Paulo GS Wadt ◽  
...  
Keyword(s):  
Near Infrared ◽  
Environmental Variability ◽  
Diffuse Reflectance Spectroscopy ◽  
Soil Classification ◽  
R Package ◽  
Chemical Components ◽  
Soil Profiles ◽  
Wide Range

The southwestern region of the Amazon has great environmental variability, presents a great complexity of pedoenvironments due to its rich variability of geological and geomorphological environments, as well as for being a transition region with other two Brazilian biomes. In this study, the use of pedometric tools (the Algorithms for Quantitative Pedology (AQP) R package and diffuse reflectance spectroscopy) was evaluated for the characterization of 15 soil profiles in southwestern Amazon. The AQP statistical package—which evaluates the soil in-depth based on slicing functions—indicated a wide range of variation in soil attributes, especially in the superficial horizons. In addition, the results obtained in the similarity analysis corroborated with the description of physical, chemical components and oxide contents in-depth, aiding the classification of soil profiles. The in-depth characterization of visible-near infrared spectra allowed inference of the pedogenetic processes of some profiles, setting precedents for future work aiming to establish analytical strategies for soil classification in southwestern Amazon based on spectral data.

Pharmacological and nutritional benefits of flaxseed’s (Linum usitatissimum Linn.) biocomponents

2022 ◽  
Vol 01 ◽  
Author(s):  
Mohammad Tarique ◽  
Badruddeen ◽  
,Shahla Parveen ◽  
Farogh Ahsan ◽  
Mohammad Irfan Khan ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Linum Usitatissimum ◽  
Muscle Growth ◽  
Health Benefits ◽  
Nutritional Composition ◽  
Chemical Components ◽  
Omega 3 ◽  
Plant Resources ◽  
Golden Yellow ◽  
Wide Range

Abstract: Linum usitatissimum (Linn.), Commonly known as flaxseed or flaxseed, belongs to the family Linaceae. Flaxseed is a crop of blue flowers that produce small, flat seeds of golden yellow to reddish-brown color. It is a native of the Mediterranean and West Asia. Due to its health benefits associated with the high content of linolenic acid (ALA), flaxseed has played a major role in diet and research. The ALA is an essential omega-3-fatty acid, and also due to its presence a major lignan, i.e. secoisolaricyrcinol diglucoside (SDG). There is also a wide range of uses of flaxseed oil in skin health, anticoagulants, anticancer, ulcer treatment, muscle growth, and weight loss. The nutritional composition of flaxseed is about 30% carbohydrate, 18% protein, and 39% fat. Flaxseed contains most carbohydrates in the form of fiber and contains more than 45% omega-3 fatty acids. It also contains dietary fibers, proteins and polyunsaturated fatty acids. All the ingredients possess different health benefits. Although plant resources are the key ingredient in drug discovery, the popularity of flaxseed always fascinate scientists, the number of articles giving information about the chemical components of flaxseed and its potential clinical use is very little. This review provides a systematic summary of the research completed over the past decade and provides an up-to-date summary of the various bioactive and outlines the relationship between the nutritional and pharmacological use of chemical ingredients and its flaxseed.

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