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POSTAGE stamps, NOBEL Prizes, NOBEL Prize in Chemistry, STAMP collecting, ANALYTICAL chemistry, ORGANIC chemistry awards, NATURAL products, BIOCHEMISTRY, and AWARDS

Nobel Prizes in Chemistry and Philately, Part II, is a review of the stamps issued in different countries to commemorate the Nobel Prizes in analytical chemistry, organic chemistry, natural products and biochemistry. [ABSTRACT FROM AUTHOR]

PHOTONS, PHYSICAL organic chemistry, PHOTOCHEMISTRY, SUPRAMOLECULAR chemistry, and NUCLEAR spin

This Perspective presents a review and survey of the science and philosophy of my research career over the past five decades at Columbia as a physical organic chemist and photochemist. I explore the role of paradigms, structure, and geometric thinking in my own cognitive and intellectual development. The Perspective describes my investigations of high energy content molecules in electronically excited states and the development of electronic spin and supramolecular photochemistry chemistry. Current research dealing with the nuclear spin chemistry of H2 incarcerated in buckyballs is illustrated. In the second part of this Perspective, I recount a personal role of the philosophy and history of science and the scientific communities' use of paradigms in their every day research and intellectual activities. Examples are given of the crucial role of geometry and structure in the rapid development of organic chemistry and physical organic chemistry over the past century. [ABSTRACT FROM AUTHOR]

POLYMER research and MASS spectrometry

Examines proposed partial least squares (PLS) multivariate statistical models for predicting concentration of hydrocarbon- and oxygen-containing functional groups for a calibration set of model homopolymers. Plasma-deposited films; Static secondary ion mass spectrometry (SIMS); PLS modeling; Preprocessing; Prediction of surface oxygen and hydrogen concentration.

Depressants are critical reagents for the selective separation of minerals in froth flotation. They serve a vital role in preferentially making the gangue minerals hydrophilic and prevent them from reporting to the mineral-rich froth phase. Current practice involves the use of inorganic depressants, which are toxic and non-biodegradable. Environmentally friendly, flexible and affordable flotation depressants are needed due to the depletion of easy-to-process high-grade ores as well as sustainability and environmental concerns. This paper discusses various organic depressants that have been adopted for selective depression of unwanted minerals in chalcopyrite flotation. The origin and chemistry, organic depressant-gangue minerals interaction mechanism, and the use of organic depressants in the most common chalcopyrite-flotation instances, including chalcopyrite separation from galena, molybdenite, sphalerite, pyrite, pyrrhotite, talc, serpentine and carbonaceous materials, are discussed. This review shows that organic depressants can partially or fully replace current inorganic depressants used in suppressing both sulfide and non-sulfide gangue minerals in chalcopyrite flotation. In this review, a well-detailed and well-referenced discussion is provided for the current state of organic depressants in chalcopyrite flotation, as well as a valuable discussion is provided to comparatively evaluate the depression performance of the various reported organic depressants. Finally, suggestions are made regarding future research challenges and directions. The recent advancements, developing features, and research prospects discussed in this article will provide a helpful reference for academics who want to delve deeper into the greening of chalcopyrite flotation process. [ABSTRACT FROM AUTHOR]

COMPOSITION of water, POLYMERS, CATALYSTS, INORGANIC chemistry, and POWER resources

The article discusses research on how the light-induced splitting of water into oxygen and hydrogen generates storable polymers and chemical fuels that could be used to address the world's energy demands. Particular attention is also given to the use of inorganic materials as semiconductor catalysts for such splits.

ANTIFUNGAL agent synthesis, STRUCTURE-activity relationships, ORGANIC chemistry, RUTHENIUM catalysts, BIOACTIVE compounds, PHARMACEUTICAL chemistry, and HETEROCYCLIC compounds

A pharmacophore system has been found as 1,2,3-triazole, a five-membered heterocycle ring with nitrogen heteroatoms. These heterocyclic compounds can be produced using azide-alkyne cycloaddition processes catalyzed by ruthenium or copper. The bioactive compounds demonstrated antitubercular, antibacterial, anti-inflammatory, anticancer, antioxidant, antiviral, and antidiabetic properties. This heterocycle molecule, in particular, with one or more 1,2,3-triazole cores has been found to have the most powerful antifungal effects. The goal of this review is to highlight recent developments in the synthesis and structure-activity relationship (SAR) investigation of this prospective fungicidal chemical. Also there have been explained drugs and mechanism of action of a triazole compound with antifungal activity. This review will be useful in a variety of fields, including medicinal chemistry, organic chemistry, mycology, and pharmacology. [ABSTRACT FROM AUTHOR]

SUSTAINABLE chemistry, ORGANIC synthesis, CHEMICAL engineering, CHEMICAL processes, INORGANIC chemistry, AMMONIUM sulfate, and METHACRYLATES

Keywords: green chemistry; industrial chemistry; organic synthesis; synthetic methods EN green chemistry industrial chemistry organic synthesis synthetic methods 1865 1869 5 01/29/21 20210126 NES 210126 B Making industry greener b : Many principles for the economic production of organic bulk chemicals, the syntheses of which have potentially the highest environmental impact, currently overlap with principles of green chemistry. For about 93 % of the 250 million tons organic chemicals produced annually by oxidation, oxygen is used as the oxidant, in most cases in combination with catalysts to achieve appropriate selectivities.[3] I Addressed Principles of Green Chemistry: Prevent Waste, Atom Economy, Reduce Derivatives, Catalysis vs. Getting Greener: Propylene Oxide O SB 2 sb is not always the most efficient oxidant, as shown in the different synthetic routes to valuable propylene oxide (Scheme 4).[5] The chlorohydrin process uses chlorine and produces CaCl SB 2 sb as the by-product and is therefore not that green. This would allow the entry into a circular economy.[18, 19] Certain initiatives involving large chemical producers were recently started to introduce a circular economy based on chemcycling in order to replace the current linear use of feedstocks.[20] Greener alternatives should also be as economic as possible. [Extracted from the article]

PHARMACEUTICAL chemistry, ORGANIC chemistry, CLERGY, CURRICULUM, and PHARMACISTS

The teaching of the Organic Chemistry for the career of Pharmaceutical Sciences of the Universidad de Oriente is sustained in relationships interdisciplinary and interdisciplinary con it bases on its principle rector: relationship structure-property-applications. The present work shows the results obtained of implementation of integrative seminars in the Pharmaceutical Organic Chemistry I and Chemistry Organic Pharmacist II for a bigger contribution in the pharmaceutical professional's formation. The methods were used: historical-logical, system focus, analysissynthesis, inductive-deductive and specialist criterion. Abilities related with the profession are shown, expressed in the analytic programs of each subject, their correspondence with the seminars and the results reached with this class type during the courses 2018-2019 and 2019-2020. The integration of the contents of the Pharmaceutical Organic Chemistry was achieved I and II, as well as with other subjects of the career, being demonstrated the narrow linking between the Organic Chemistry and the pharmaceutical specialty. [ABSTRACT FROM AUTHOR]

Freshwater lakes are essential hotspots for the removal of excessive anthropogenic nitrogen (N) loads transported from the land to coastal oceans. The biogeochemical processes responsible for N removal, the corresponding transformation rates and overall removal efficiencies differ between lakes, however, it is unclear what the main controlling factors are. Here, we investigated the factors that moderate the rates of N removal under contrasting trophic states in two lakes located in central Switzerland. In the eutrophic Lake Baldegg and the oligotrophic Lake Sarnen, we specifically examined seasonal sediment porewater chemistry, organic matter sedimentation rates, as well as 33-year of historic water column data. We find that the eutrophic Lake Baldegg, which contributed to the removal of 20 ± 6.6 gN m−2 year−1, effectively removed two-thirds of the total areal N load. In stark contrast, the more oligotrophic Lake Sarnen contributed to 3.2 ± 4.2 gN m−2 year−1, and had removed only one-third of the areal N load. The historic dataset of the eutrophic lake revealed a close linkage between annual loads of dissolved N (DN) and removal rates (NRR = 0.63 × DN load) and a significant correlation of the concentration of bottom water nitrate and removal rates. We further show that the seasonal increase in N removal rates of the eutrophic lake correlated significantly with seasonal oxygen fluxes measured across the water–sediment interface (R2 = 0.75). We suggest that increasing oxygen enhances sediment mineralization and stimulates nitrification, indirectly enhancing denitrification activity. [ABSTRACT FROM AUTHOR]

HIGH throughput screening (Drug development), COMBINATORIAL chemistry, ORGANIC chemistry, EXPECTED returns, ANIMAL species, and NEUROTRANSMITTERS

Drug development from natural products precedes human history by thousands of years. Mankind has learned to take the advantages of such discovered principles by nature which they now used to treat human diseases. Since, owing to the close evolutionary history with plants and animals species, many metabolites that they produce, mimics the human biological activities such as the neurotransmitters, enzymes and hormones. Therefore, many metabolites that plants and animals produce are now used by human being to treat the diseases like diabetes, cancer, microbial infections and Alzheimer's disease. The advent of combinatorial chemistry, organic chemistry and high throughput screening (HTS) has developed many lead molecules to treat human diseases. Unfortunately, these renewed techniques did not bring any expected returns in terms of new drug discoveries and therefore many researchers have shifted their research efforts back to the natural products to discover and develop the multidimensional and multibroadspectrum medicines using genomic engineering, combinatorial mucobiosynthesis and modern analytical techniques. In the present review, we have discussed comprehensively the journey of modern medicines with their prospects and promises. [ABSTRACT FROM AUTHOR]

ORGANIC synthesis, SPECTROMETRY, ASTRONOMICAL observations, and NUCLEAR magnetic resonance spectroscopy

Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine‐intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state‐of‐the‐art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined. [ABSTRACT FROM AUTHOR]

ABSTRACTING & indexing services, BIBLIOMETRICS, ORGANIC chemistry, COMPUTER software, DATABASES, INTERNET, LANGUAGE & languages, NEEDS assessment, PROFESSIONAL peer review, PUBLISHING, SERIAL publications, INFORMATION resources, ACCESS to information, PERIODICAL articles, and IMPACT factor (Citation analysis)

Subject librarians are well-positioned to apply and teach searching techniques using online library resources for assisting researchers and scholars on where to publish. A bibliometric analysis was used to compare four premier letters journals in organic chemistry: Bioorganic & Medicinal Chemistry Letters, Letters in Organic Chemistry, Organic Letters, and Tetrahedron Letters. The objective of this study is to develop a routine methodology for evaluating and comparing journals with a similar scope based on researchers' immediate needs. The study provides a practical guide to help organic chemists decide where to submit a short article for publication. For initial comparative purposes, general parameters, such as subscription rate, open access availability and article processing charge, field categories, language, maximum page length, citation style, peer-review type, review time, publication frequency, impact factor, journal h-index, acceptance rate, and database coverage were obtained from various online resources. Between 1999 and 2016, a total of 20,675 articles from Bioorganic & Medicinal Chemistry Letters, 1,732 articles from Letters in Organic Chemistry, 24,889 articles from Organic Letters, and 34,380 articles from Tetrahedron Letters were retrieved from the advanced search option in Web of Science Core Collection (Science Citation Index Expanded). The articles were examined by year, language, country, and organization. The VOSviewer software was employed for an in-depth map analysis of the research topics covered in each journal derived from key terms in article titles. The SciFinder database was used to compare similarities and differences from the articles in each letters journal through Chemical Abstracts indexing. [ABSTRACT FROM AUTHOR]

Subject librarians are well-positioned to apply and teach searching techniques using online library resources for assisting researchers and scholars on where to publish. A bibliometric analysis was used to compare four premier letters journals in organic chemistry: Bioorganic & Medicinal Chemistry Letters, Letters in Organic Chemistry, Organic Letters, and Tetrahedron Letters. The objective of this study is to develop a routine methodology for evaluating and comparing journals with a similar scope based on researchers’ immediate needs. The study provides a practical guide to help organic chemists decide where to submit a short article for publication. For initial comparative purposes, general parameters, such as subscription rate, open access availability and article processing charge, field categories, language, maximum page length, citation style, peer-review type, review time, publication frequency, impact factor, journal h-index, acceptance rate, and database coverage were obtained from various online resources. Between 1999 and 2016, a total of 20,675 articles from Bioorganic & Medicinal Chemistry Letters, 1,732 articles from Letters in Organic Chemistry, 24,889 articles from Organic Letters, and 34,380 articles from Tetrahedron Letters were retrieved from the advanced search option in Web of Science Core Collection (Science Citation Index Expanded). The articles were examined by year, language, country, and organization. The VOSviewer software was employed for an in-depth map analysis of the research topics covered in each journal derived from key terms in article titles. The SciFinder database was used to compare similarities and differences from the articles in each letters journal through Chemical Abstracts indexing. [ABSTRACT FROM AUTHOR]

TETRAPHENYLETHYLENE, THERAPEUTICS, LUMINOPHORES, ORGANIC electronics, and SUPRAMOLECULAR chemistry

[Display omitted] • Various luminogens with AIE property (AIEgens) have been broadly utilized in biomedical field. • Tetraphenylethylene derivatives have demonstrated as most promising AIEgen due to their capability of self-organization and conjugation. • They are used in different fields including organic and therapeutic science, supramolecular chemistry, organic electronics and cancer therapy. • This review encompasses the recent advances of TPE based AIE-active luminophores and their potential applications in biomolecular science. The development of aggregation-induced emission (AIE) has received extreme considerations from basic and clinical researches. To date, various luminogens with AIE property (AIEgens) have been broadly utilized in optoelectronic devices, fluorescent bio-probes, drug delivery, anticancer and chemosensors and many more. Scientists have likewise dedicated to investigating the possibilities of AIEgens in the biomedical field. Among the various AIE luminophores studied, tetraphenylethylene (TPE) derivatives have demonstrated as most promising AIEgen, owing to their capacity in self-organization and conjugation with aggregation-caused quenching (ACQ) fluorophores to form larger multi-component assemblies. It likewise generally utilized in different fields, like organic and therapeutic science, supramolecular chemistry, organic electronics, cancer therapy, apoptosis and inflammation, microorganism imaging therapy etc. This review encompasses the recent advances of TPE based AIE-active luminophores and their potential applications in biomolecular science. [ABSTRACT FROM AUTHOR]

CLICK chemistry, ORGANIC synthesis, FLUORIDES, CHEMICAL amplification, MATERIALS science, and DESULFURIZATION

The sulfur(VI) fluoride exchange reaction (SuFEx), developed by Sharpless and co-workers in 2014, is a new category of click reaction that creates molecular connections with absolute reliability and unprecedented efficiency through a sulfur(VI) hub. Ethenesulfonyl fluoride (ESF), as one of the most important sulfur(VI) hubs, exhibits extraordinary reactivity in SuFEx click chemistry and organic synthesis. This review summarizes the chemical properties and applications of ESF in click chemistry, organic chemistry, materials science, medicinal chemistry and in many other fields related to organic synthesis. 1 Introduction 2 Chemical Transformations of ESF 3 Chemical Transformations of 2-Arylethenesulfonyl Fluorides 4 Novel SuFEx Reagents Derived from ESF 5 Applications of ESF Derivatives in Medicinal Chemistry 6 Applications of ESF Derivatives in Materials Science 7 Conclusion [ABSTRACT FROM AUTHOR]

VOLATILE organic compounds, OPTICAL properties of atmospheric aerosols, ATMOSPHERIC chemistry, ATMOSPHERIC research, HYDROCARBONS, GLOBAL temperature changes, and MOUNTAINS

Mean temperature anomalies in the Southeastern United States (SEUS) over the past century have reflected regional cooling hypothesized to be a result of an enhancement of warm season aerosol optical thickness caused by the oxidation of biogenic volatile organic compounds (VOCs). Aerosol and gas-phase VOC measurements were made at the Appalachian Atmospheric Interdisciplinary Research (AppalAIR) site in the southern Appalachian mountains of North Carolina during the summer of 2013 in an effort to characterize warm season chemistry. Organic aerosol (OA) chemistry was characterized through a positive matrix factorization analysis resolving a low-volatility, semi-volatile, and isoprene oxidation factor contributing 34 ± 15, 24 ± 12, and 42 ± 17 %, respectively to the total observed OA. Volatile organic compound characterization described chemistry that was typical of rural background levels with periods of elevated hydrocarbon and urban tracer loading that varied with synoptic flow. Chemical, meteorological, and aerosol optical property data suggested that measurements made at the AppalAIR site are representative of background atmospheric chemistry in the SEUS. Annual background secondary organic aerosol (SOA) production in the SEUS was estimated to be 0.15-0.50 GgC yr. Estimates of total and background SOA from this study provide evidence that the SEUS is a region of global significance in the context of global SOA budgets, and can be useful in understanding the extent of anthropogenic enhancement of summertime SOA compared to background levels. [ABSTRACT FROM AUTHOR]

ORGANIC chemistry research, CHEMICAL synthesis, METAL complexes, CATALYSIS, CHEMISTS, and SCIENTISTS

The article comments on the article "The Reasons Organic Chemistry is Needed for in a Well Developed Country," by I.P. Beletskaya and V.P. Ananikov, published in this journal. It discusses need for a strong effort to get positive results in the fields of Russian chemistry, organic synthesis, and metal complex catalysis; need for the development of new methods and reactions for the formation of desired materials; and role of young researchers in the development of organic chemistry in Russia.

INORGANIC chemistry, SUPRAMOLECULAR chemistry, CHEMICAL properties, BIOENERGETICS, ORGANIC chemistry, and METAL-organic frameworks

This review summarizes the recent research progress in boron-based metal–organic materials, including MOFs, MOCs and metallacycles with their synthesis, properties and potential applications. [Display omitted] • During the past few decades, metal–organic materials (MOMs) including metal–organic frameworks (MOFs), metal–organic cages (MOCs) and metallacycles have captured widespread interest because of their wide applications in gas storage and separation, catalysis, sensor, energy storage and biological relevant applications. • Thus, exploring new MOMs, studying their physical and chemical properties and applications have become one of the most active and exciting areas of inorganic chemistry, organic chemistry and supramolecular chemistry. • Among which, boron-based MOMs, constructed from the boron containing ligands, have attracted considerable attention because of the unique properties of boron atom, which arises from their unoccupied 2p orbital, endowing these materials with unique potentials in light-harvesting, catalysis, fluorescent sensing, biomedical, etc. • Although metal–organic materials have received extensive attention and a number of reviews have increased sharply, surprisingly, there is no specific review summarizing the boron-based metal–organic materials to the best of our knowledge and a comprehensive review in this field is needed. • Thus, it will be of great benefit for the research community to summarize this research field. • This review aims to provide a comprehensive overview of boron-based metal–organic materials with an emphasis on the design, synthesis, properties and applications. During the past few decades, metal–organic materials (MOMs) including metal–organic frameworks (MOFs), metal–organic cages (MOCs) and metallacycles have captured widespread interests due to their wide applications in energy storage, catalysis, sensor, gas storage and separation, and biological relevant applications. Thus, exploring new MOMs, studying their physical and chemical properties and applications have become one of the most attractive and exciting areas of inorganic chemistry, organic chemistry and supramolecular chemistry. Among which, boron-based metal–organic materials (BMOMs), constructed from the boron-containing ligands, have attracted considerable attention because of the unique properties of boron atom, which arises from their unoccupied 2p orbital, endowing these materials with unique potentials in light-harvesting, catalysis, fluorescent sensing, biomedical, etc. In this Review, we summarize the recent research progress in BMOMs, including MOFs, MOCs and metallacycles with their synthesis, properties and potential applications. [ABSTRACT FROM AUTHOR]

ATMOSPHERIC chemistry, ORGANIC chemistry, POLLUTANTS, CHEMICAL processes, AMMONIUM sulfate, and CLOUD condensation nuclei

Keywords: atmospheric aqueous-phase chemistry; multiphase chemistry; organic pollutants; inorganic species; kinetic studies; mechanistic studies; chemical mechanisms; modeling EN atmospheric aqueous-phase chemistry multiphase chemistry organic pollutants inorganic species kinetic studies mechanistic studies chemical mechanisms modeling 3 3 1 02/02/21 20210101 NES 210101 The Atmosphere Special Issue "Atmospheric Aqueous-Phase Chemistry" comprises ten original articles dealing with different aspects of chemistry in atmospheric liquid water. Dissolved species from the soluble aerosol fraction as well as soluble trace gases undergo chemical reactions in the aqueous phase via different mechanisms, usually yielding different products from those in the gas phase. Their rough estimations showed that the gas-phase reactions of 2-nitrophenol (2-NP) with OH or NO SB 3 sb radicals dominate over the aqueous-phase reaction with SO SB 4 sb SP - sp in deliquescent aerosol and haze. [Extracted from the article]

With the consumption of fossil resources, biomass materials have become a popular research topic. Natural vegetable oils, particularly Tung oil, are well-known to agricultural and forestry colleges/universities as best raw materials for producing biomass materials. The writers design an organic synthetic chemical experiment. Designed by specialty of Applied Chemistry and Materials Chemistry as a research-oriented practice, this experiment can be generated at agricultural and forestry colleges/universities, because the synthesis step is simple, easy to understand and master, and it covers key knowledge of related disciplines, including structural inorganic chemistry, organic synthesis chemistry, polymer chemistry, instrumental analysis, spectroscopy, etc. In the teaching practice, tutors can apply various measures, e. g. , key points analysis, literature review, experiment design and practice, group work, data processing and result analysis, to deepen students' understanding of theories, improve operational skills in chemical experiments, develop abilities to analyze and solve problems, foster research innovation, and enhance their awareness of environmental protection and social responsibilities. [ABSTRACT FROM AUTHOR]