Synthesis and Kinetic Investigations for the Isomerization Process of 2–Hydroxy Chalcone Derivatives

The wide biological activities of flavanones are mainly depends on their physical and chemical properties, thus a number of substituted 2-Hydroxy chalcones have been synthesized, and their isomerization to their corresponding flavanones was studied. In order to determine the rate constant, kinetic experiments were performed using HPLC technique in (9:1) (CH3CN:H2O) medium at different temperature (298-318) K. The obtained results were interpreted by four steps mechanism, which considered the existence of phenoxide ion as the key intermediate. This study performed with a pseudo first order ( reaction in which the rate for the studied compounds follow the sequence 5 andgt; 2 andgt; 1 andgt; 4 andgt; 3, the activation energy have the same sequence for these compounds .The effect of substituents on the rate showed that electronic and steric factors play reasonable role on the stability of the product .

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The Establishment of the 3rd National Reference Standard for Tachypleus Tridentatus Lysate

Journal of Applied Virology ◽

10.21092/jav.v6i3.90 ◽

2017 ◽

Vol 6 (3) ◽

pp. 50

Author(s):

Tong Cai ◽

Guolai Zhang ◽

Yusheng Pei ◽

Hua Gao

Keyword(s):

Chemical Properties ◽

Physical And Chemical Properties ◽

Reference Standard ◽

Tachypleus Tridentatus ◽

National Reference ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

Objective To establish the 3rd national reference standard for Tachypleus Tridentatus Lysate Reagent. Method and Results The candidates of reference standard were studied for the physical and chemical properties, and the stability. To determined its sensitivity by collaboration calibration. Conclusions The sensitivity of the 3rd national reference standard for TAL is 0.06EU / ml, lot number is 150603-201003.

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Biophysical Characterization and Anticancer Activities of Photosensitive Phytoanthraquinones Represented by Hypericin and Its Model Compounds

Molecules ◽

10.3390/molecules25235666 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5666

Author(s):

Valéria Verebová ◽

Jiří Beneš ◽

Jana Staničová

Keyword(s):

Photodynamic Therapy ◽

Biological Activities ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Anticancer Activities ◽

Model Compounds ◽

Antitumor Effects ◽

Biophysical Characterization ◽

Physical And Chemical ◽

And Chemical Properties

Photosensitive compounds found in herbs have been reported in recent years as having a variety of interesting medicinal and biological activities. In this review, we focus on photosensitizers such as hypericin and its model compounds emodin, quinizarin, and danthron, which have antiviral, antifungal, antineoplastic, and antitumor effects. They can be utilized as potential agents in photodynamic therapy, especially in photodynamic therapy (PDT) for cancer. We aimed to give a comprehensive summary of the physical and chemical properties of these interesting molecules, emphasizing their mechanism of action in relation to their different interactions with biomacromolecules, specifically with DNA.

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Salting-out and salting-in experiments with lignosulfonates (LSs)

Holzforschung ◽

10.1515/hf-2012-0163 ◽

2013 ◽

Vol 67 (5) ◽

pp. 549-557 ◽

Cited By ~ 12

Author(s):

Bernt O. Myrvold

Keyword(s):

Chemical Properties ◽

Physical And Chemical Properties ◽

Salting Out ◽

Practical Applications ◽

Common Ion ◽

The Common ◽

Common Ion Effect ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

Abstract The solubility of lignosulfonates (LSs) in water is strongly dependent on other ions present in the water phase. The differences in the solubility might strongly influence the measurements of the physical and chemical properties of the LS molecules. A reduced solubility of the LS might also affect its utility in many practical applications. The understanding of the interaction between LSs and various salts is important for both practical and theoretical reasons. Therefore, the effect of salt concentrations on the LS has been investigated for 41 different salts with 14 different cations and 16 different anions. The observations cannot be explained by the common ion effect or the screening effects. On the contrary, it was found that the stability of LS solutions follows the Hofmeister series, with the exception of those ions that will chemically interact with the LS molecule. Moreover, the positions of phosphate (HPO42-) and sulfate (SO42-) ions were reversed.

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Use of Cerium Nitrate Nanoparticles in Biological Environment Along with the Factors Effecting It: An Empirical Overview

10.20944/preprints202108.0537.v1 ◽

2021 ◽

Author(s):

Zarish Fatima ◽

Sameer Quazi ◽

Shreelaxmi Gavas ◽

Tomasz Karpiński

Keyword(s):

Biological Activities ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Medical Field ◽

Physiochemical Properties ◽

Synthesis Of Nanoparticles ◽

Biological Environment ◽

Physical And Chemical ◽

Nano Ceria ◽

And Chemical Properties

The advancement in the production and usage of the cerium oxide nanoparticles have diverted the attention of scientists towards their usage in medical field and therapeutic usage. The clinical usage of these Nano ceria is based on their ability to moderate the oxidative stress and this is only because of their ability to change their valent state from +3 to +4 which makes them ideal for scavenging radicals for use in a number of systemic and neurodegenerative disorders. This review aims to synthesize the basic methods used for the synthesis of nanoparticles along with the use of ligand, stabilizing agent and other components. This review also concludes that how various physical and chemical properties of nanoparticles effect the basic biological activities such as antimicrobial activity, cytotoxicity and many others. However, during the standardization, some of the physiochemical properties, methods used for preparation and catalytic abilities must be taken into account.

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Agrochemical properties of soils of land plots of the Park «Tikhiy Otdykh» of Saint Petersburg

Известия СПбЛТА ◽

10.21266/2079-4304.2021.234.102-117 ◽

2021 ◽

pp. 102-117

Author(s):

В.Ф. Ковязин ◽

П.М. Демидова ◽

Е.А. Иванова

Keyword(s):

Geographical Information Systems ◽

Current Problem ◽

Chemical Properties ◽

Geographical Information ◽

Physical And Chemical Properties ◽

Saint Petersburg ◽

Agrochemical Properties ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

Статья посвящена актуальной проблеме формирования устойчивости парковых насаждений, произрастающих на почвах с различными физико-химическими свойствами. Приведены характерные агрохимические свойства почв парка «Тихий отдых» Санкт-Петербурга. По каждому агрохимическому показателю почвы разработаны с использованием современных географических информационных систем (ГИС) тематические карты в масштабе 1:10000 с применением программного комплекса AutoCAD. С использованием данного комплекса рассчитаны площади земельных угодий, имеющих различные физико-химические свойства почвы. В настоящее время данная проблема городских садово-парковых объектов мало изучена и требует дальнейших исследований, именно этой тематике и посвящены изложенные в статье результаты исследований. The article is devoted to the current problem of forming the stability of Park stands growing on soils with different physical and chemical properties. The characteristic agrochemical properties of the soils of the Park «Tikhiy Otdykh» of St. Petersburg are given. For each agrochemical indicator of the soil, thematic maps were developed using modern geographical information systems (GIS) at a scale of 1:10000 using the AutoCAD software package. Using this complex, the areas of land with different physical and chemical properties of the soil are calculated. At present, this problem of urban garden and Park objects is poorly studied and requires further research. These results presented in the article are devoted to this topic.

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Grafting of Hydroxy-Terminated Polybutadiene with 2-Mercaptoethanol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20021899 ◽

2002 ◽

Vol 67 (12) ◽

pp. 1899-1910 ◽

Cited By ~ 1

Author(s):

Alexander Pleska ◽

Iva Klichová ◽

Jindřich Pytela

Keyword(s):

Chemical Properties ◽

Radical Addition ◽

Physical And Chemical Properties ◽

Scanning Calorimetry ◽

Polyurethane Elastomers ◽

Volatile Solvents ◽

Hydrolytic Resistance ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

A method for functionalization of hydroxy-terminated polybutadiene with 2-sulfanylethan-1-ol (2-mercaptoethanol) leading to a controlled increase in the OH functionality of the polymer was developed. The polybutadiene used contained about 65% of unsaturation in the form of 1,2-vinyl groups. The reaction was carried out without using volatile solvents. The radical addition of 2-sulfanylethan-1-ol on the polymer proceeded quantitatively and the products were free of the mercaptan odour. A series of functionalized polybutadienes were synthesized and characterized by their physical and chemical properties. The differential scanning calorimetry and thermogravimetric analysis measurements revealed that the functionalization improves the stability of the polybutadiene to thermooxidation. The obtained polymers were used for the preparation of polyurethane elastomers. The effect of the increased functionality of the polybutadiene on mechanical properties, thermal behavior and hydrolytic resistance of the elastomers was assessed.

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Dyeing of Innovative Bicomponent Filament Fabrics (PET/PTT) by Disperse Dyestuffs: Characterization and Optimization Process

Processes ◽

10.3390/pr8050501 ◽

2020 ◽

Vol 8 (5) ◽

pp. 501 ◽

Cited By ~ 1

Author(s):

Marwa Souissi ◽

Ramzi Khiari ◽

Wafa Haddar ◽

Mounir Zaag ◽

Nizar Meksi ◽

...

Keyword(s):

Elastic Recovery ◽

Chemical Properties ◽

Disperse Dyes ◽

Physical And Chemical Properties ◽

Color Strength ◽

Scanning Calorimetry ◽

Dyeing Process ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

PET/PTT bicomponent filaments yarn is produced by two polymers: the polyethylene terephthalate (PET) and the polytrimethylene terephtalate (PTT) extruded side by side. This yarn is known for its high mechanical properties in particular elasticity and elastic recovery. However, differences between physical and chemical properties of the two components make the dyeing step of this yarn complicated. The aim of this work is the development of a dyeing process for bicomponent filaments without altering their physical and chemical properties. Different techniques such as SEM, FTIR, and differential scanning calorimetry (DSC) were used to characterize the studied yarn. For dyeing, three different disperse dyes CI Disperse Red 167.1, CI Disperse Yellow 211, and CI Disperse Red 60 with different energy classes were studied. The influence of dyeing conditions in particular dyeing temperature, pH of dye bath, dyeing time, and carrier concentration in the dye bath was evaluated. Responses analyzed are color strength (K/S), colorimetric coordinates and color fastness of samples dyed with studied dyes. In addition, the stability of elasticity and elastic recovery of bicomponent filament fabrics after the dyeing process has been also verified and proved.

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REACTIONS OF ORGANOTIN COMPOUNDS: I. THE STABILITY OF DIMETHYLTIN DIHYDRIDE, AND ADDITIONS TO SOME FLUORO-OLEFINS

Canadian Journal of Chemistry ◽

10.1139/v63-423 ◽

1963 ◽

Vol 41 (11) ◽

pp. 2889-2897 ◽

Cited By ~ 14

Author(s):

H. C. Clark ◽

Sharon G. Furnival ◽

J. T. Kwon

Keyword(s):

Ultraviolet Light ◽

Ultraviolet Irradiation ◽

Chemical Properties ◽

Addition Product ◽

Organotin Compounds ◽

Physical And Chemical Properties ◽

Decomposition Products ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

The effect of heat and ultraviolet irradiation on dimethyltin dihydride is reported. At 120°, the major decomposition products are (CH3)3SnH, Sn, and H2, with a small amount of (CH3)6Sn2. At 130° under ultraviolet light, decomposition is much more rapid giving (CH3)3SnH, Sn, and H2, and an appreciable quantity of (CH3) 4Sn. If the dihydride is maintained under these conditions for a longer period (40 hours), (CH3)6Sn2 is formed in place of (CH3)3SnH, and other products are (CH3)4Sn, Sn, and H2. Negligible decomposition occurs at 25° even under irradiation.The ready addition of C2F4 to (CH3)2SnH2 gives the first reported mono-addition product of an organotin dihydride, (CH3)2SnH(C2F4H), as well as (CH3)2Sn(C2F4H)2. Physical and chemical properties of these compounds are described. The additions of (CH3)2SnH2 to CF2CFH, CF2CH2, and CF2CFBr are reported and the results interpreted in terms of the formation of unstable mono-addition products, (CH3)2SnH(C2FnXmHp). Surprisingly, these species decompose through the exchange of halogen and hydrogen between (CH3)2SnH2 and the olefin. Thus, usual products from the reaction of (CH3)2SnH2 with CF2CFBr are (CH3)2SnBr2 and CF2CFH, with some (CH3)3SnBr.

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Some Properties of Oil Emulsions Influencing Insecticidal Efficiency

Illinois Natural History Survey Bulletin ◽

10.21900/j.inhs.v17.284 ◽

1928 ◽

Vol 17 (1-12) ◽

pp. 235-259

Author(s):

L. L. English

Keyword(s):

Good Reason ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Emulsifying Agent ◽

Oil Emulsions ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

It is very difficult to isolate any one property of an emulsion and determine separately its action on insects. The physical and chemical properties of the oil, the kind and amount of emulsifying agent, and the stability of the emulsion are all so closely interlocked that one property usually cannot be varied without changing the others. There is good reason for believing that no two emulsions—and, very likely, no two lots of an emulsion made by the same formula—are exactly alike.

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Physical and Chemical Properties of Polycyclic Aromatic Hydrocarbons

Symposium - International Astronomical Union ◽

10.1017/s0074180900125197 ◽

1989 ◽

Vol 135 ◽

pp. 155-171

Author(s):

S. Leach

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Interstellar Medium ◽

Aromatic Hydrocarbons ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Polycyclic Aromatic ◽

The Stability ◽

Physical And Chemical ◽

And Chemical Properties

A review is presented of some physical and chemical properties of polycyclic aromatic hydrocarbons (PAHs) that are relevant for interpreting various aspects of observations and speculations on PAHs in the interstellar medium. The subjects discussed are: the stability and reactivity of neutral and ionic PAHs; the spectroscopy and photophysics of neutral and monocationic PAHs; the photostabilities of PAH monocations and dications and their astrophysical implications.

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