Ag2S2O8 meets AgSO4: the second example of metal–ligand redox isomerism among inorganic systems

2016 ◽  
Vol 45 (45) ◽  
pp. 18202-18207 ◽  
Author(s):  
Tomasz E. Gilewski ◽  
Piotr J. Leszczyński ◽  
Armand Budzianowski ◽  
Zoran Mazej ◽  
Adam Grzelak ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Inorganic Systems ◽  
Redox Isomerism ◽  
First Time ◽  
Identical Chemical Composition ◽  
Metal Ligand

Ag(i)2S2O8 – prepared here for the first time – constitutes a redox isomer of the already known Ag(ii)SO4. These “electromers” have identical chemical composition but they differ in all important physicochemical properties.

scholarly journals A First Approach to the Chemical Composition and Antioxidant Potential of Guinea-Bissau Propolis

2019 ◽  
Vol 14 (5) ◽  
pp. 1934578X1984413 ◽  
Author(s):  
Soraia I. Falcão ◽  
Mélissa Lopes ◽  
Miguel Vilas-Boas
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Physicochemical Properties ◽  
Natural Product ◽  
Broad Spectrum ◽  
Biological Activities ◽  
Chemical Diversity ◽  
Antioxidant Potential ◽  
Phenolic Composition ◽  
First Time

Propolis is a natural product derived from plant resins collected by honeybees and used in the beehive as a construction and defensive material. The broad spectrum of biological activities is dependent on the chemical diversity of its composition which is determined by the floral sources at the site of collection. For the first time, the chemical composition of Guinean propolis as well as its physicochemical properties, phenolic composition, and antioxidant activity was assessed. Eight compounds were identified through LC/DAD/ESI-MS n , mostly isoflavonoids, resembling Nigerian and Brazilian red propolis from the genus Dalbergia.

scholarly journals Changes of Physicochemical Properties of Starch Syrups Recommended for Winter Feeding of Honeybees during Storage

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 374
Author(s):  
Teresa Szczęsna ◽  
Ewa Waś ◽  
Piotr Semkiw ◽  
Piotr Skubida ◽  
Katarzyna Jaśkiewicz ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Physicochemical Parameters ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Different Temperatures ◽  
And Storage ◽  
Bee Colonies ◽  
Temperature Time ◽  
Winter Feeding

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.

scholarly journals Non-invasive sensing for food reassurance

The Analyst ◽  
2016 ◽  
Vol 141 (5) ◽  
pp. 1587-1610 ◽  
Author(s):  
Zou Xiaobo ◽  
Huang Xiaowei ◽  
Malcolm Povey
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Food Quality ◽  
Physical Principle ◽  
Quality Traits ◽  
X Ray ◽  
Main Food ◽  
Non Invasive ◽  
Wide Range ◽  
Nutritional Characteristics

The main food quality traits of interest using non-invasive sensing techniques are sensory characteristics, chemical composition, physicochemical properties, health-protecting properties, nutritional characteristics and safety. A wide range of non-invasive sensing techniques, from optical, acoustical, electrical, to nuclear magnetic, X-ray, biosensor, microwave and terahertz, are organized according to physical principle.

Chemical Composition of Volatile Oil from Cinnamomum zeylanicum Buds

2002 ◽  
Vol 57 (11-12) ◽  
pp. 990-993 ◽  
Author(s):  
Guddadarangavvanahally K. Jayaprakasha ◽  
Lingamallu Jaganmohan Rao ◽  
Kunnumpurath K. Sakariah
Keyword(s):  
Chemical Composition ◽  
Volatile Oil ◽  
Cinnamomum Zeylanicum ◽  
First Time

The hydro-distilled volatile oil of the Cinnamomum zeylanicum (C. zeylanicum) buds was analyzed using GC and GC-MS for the first time. Thirty-four compounds representing ≈ 98% of the oil was characterized. It consists of terpene hydrocarbons (78%) and oxygenated terpenoids (9%). α-Bergamotene (27.38%) and α-copaene (23.05%) are found to be the major compounds. A comparison of the chemical composition of the oil was made with that of flowers and fruits.

Sb-V-Ox catalysts—Role of chemical composition of MCM-41 supports in physicochemical properties

2009 ◽  
Vol 142 (3-4) ◽  
pp. 175-180 ◽  
Author(s):  
H. Golinska ◽  
P. Decyk ◽  
M. Ziolek ◽  
J. Kujawa ◽  
E. Filipek
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Mcm 41

scholarly journals Towards a better understanding of the origins, chemical composition and aging of oxygenated organic aerosols: case study of a Mediterranean industrialized environment, Marseille

2013 ◽  
Vol 13 (15) ◽  
pp. 7875-7894 ◽  
Author(s):  
I. El Haddad ◽  
B. D'Anna ◽  
B. Temime-Roussel ◽  
M. Nicolas ◽  
A. Boreave ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Organic Aerosols ◽  
Industrial Emissions ◽  
Aerosol Mass Spectrometer ◽  
Statistical Confidence ◽  
Aerosol Mass ◽  
Novel Approach ◽  
Organic Markers ◽  
The Impact ◽  
First Time

Abstract. As part of the FORMES summer 2008 experiment, an Aerodyne compact time-of-flight aerosol mass spectrometer (cToF-AMS) was deployed at an urban background site in Marseille to investigate the sources and aging of organic aerosols (OA). France's second largest city and the largest port in the Mediterranean, Marseille, provides a locale that is influenced by significant urban industrialized emissions and an active photochemistry with very high ozone concentrations. Particle mass spectra were analyzed by positive matrix factorization (PMF2) and the results were in very good agreement with previous apportionments obtained using a chemical mass balance (CMB) approach coupled to organic markers and metals (El Haddad et al., 2011a). AMS/PMF2 was able to identify for the first time, to the best of our knowledge, the organic aerosol emitted by industrial processes. Even with significant industries in the region, industrial OA was estimated to contribute only ~ 5% of the total OA mass. Both source apportionment techniques suggest that oxygenated OA (OOA) constitutes the major fraction, contributing ~ 80% of OA mass. A novel approach combining AMS/PMF2 data with 14C measurements was applied to identify and quantify the fossil and non-fossil precursors of this fraction and to explicitly assess the related uncertainties. Results show with high statistical confidence that, despite extensive urban and industrial emissions, OOA is overwhelmingly non-fossil, formed via the oxidation of biogenic precursors, including monoterpenes. AMS/PMF2 results strongly suggest that the variability observed in the OOA chemical composition is mainly driven in our case by the aerosol photochemical age. This paper presents the impact of photochemistry on the increase of OOA oxygenation levels, formation of humic-like substances (HULIS) and the evolution of α-pinene SOA (secondary OA) components.

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