Physico-chemical factors conditioning the electronic conduction of conductive polymers

The driving idea and the main objective of this synthetic work is the study of physicochemical factors such as the dielectric constant of the solvent, the polarizability of the chains and the Gap energy of the conductive polymers, these characteristics condition their properties. electrical and electrochemical. We focused our study on polyaniline, two synthetic methods are presented: chemical polymerization and electropolymerization with emphasis on the theoretical aspects of the phenomena involved as well as on the electrochemical methods used such as cyclic voltammetry. We have therefore developed with maximum clarity the links existing between the physico-chemical properties of polyaniline and its electrical conductivity.

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Ichthyofaunal Diversity and Physico-Chemical Factors of Melamchi River, Sindhupalchok, Nepal

Journal of Institute of Science and Technology ◽

10.3126/jist.v21i1.16031 ◽

2016 ◽

Vol 21 (1) ◽

pp. 10-18

Author(s):

Abha R. Mishra ◽

Chitra Bahadur Baniya

Keyword(s):

Fish Species ◽

Fish Community ◽

Diversity Index ◽

Chemical Properties ◽

Habitat Characteristics ◽

Fish Diversity ◽

Physico Chemical ◽

Chemical Factors ◽

High Level

The fish community and physico-chemical properties at five sites of Melamchi River were studied monthly from January 2011 to December 2013. Melamchi River is one of tributaries larger Indrawati River basin, originates from the high snowy Jugal Mountain (5,875 m asl). Eleven fish species within two orders and five families were recorded. Cypriniformes was found to be the most dominant order with ten fish species. Schizothorax plagiostomus was the most common fish species followed by Neolissochilus hexagonolepis, and Psilorhynchus pseudecheneis. Shannon Wiener fish diversity index and species richness recorded were highest at site 2 and lowest at site 5, whereas, evenness index was highest at site 3. The cluster analysis revealed that similarity between fish species decreased as the distance between the sites increased. Fish species were found distributed among four groups with respect to the significant habitat characteristics in the redundancy analysis (RDA). River water was found well-oxygenated and alkaline at all sites. However, high level for turbidity (43.25/ NTU) was observed at site 5, which exceeded compliance levels of WHO indicating the influence of intensive agriculture and deforestation along river area. To improve fish diversity and water quality of this river proper monitoring and management are an urgent need.Journal of Institute of Science and TechnologyVolume 21, Issue 1, August 2016, Page: 10-18

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Exploring New Synthetic Strategies for the Production of Advanced Complex Inorganic Nanocrystals

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2014-0611 ◽

2015 ◽

Vol 229 (1-2) ◽

Cited By ~ 4

Author(s):

Neus G. Bastús ◽

Edgar Gonzalez ◽

Joan Esteve ◽

Jordi Piella ◽

Javier Patarroyo ◽

...

Keyword(s):

Materials Science ◽

Chemical Properties ◽

Synthetic Methods ◽

Colloidal Synthesis ◽

Hollow Structures ◽

Physico Chemical ◽

Composition And Structure ◽

Wide Range ◽

Potential Applicability ◽

New Generation

AbstractThe design of new protocols for the colloidal synthesis of complex nanocrystals (NCs) with advanced functionalities, comprising both hybrid and hollow structures, and the study of their fundamental properties is of paramount importance for the development of a new generation of nanostructured materials. The possibility of tailoring the dimensional regime of NCs, along with its composition and structure, represents a landmark achievement in the control of their unique physico-chemical properties. These properties, alongside with the ability to cheaply produce high quality NCs in fairly large amounts by wet-chemistry techniques, leads to their potential applicability from materials science to nanomedicine. Within this context, this review is focused on describing a successful framework for designing synthetic strategies for the production of advanced complex NCs, integrating the development of new synthetic methods with its structural characterization, monitoring of their properties, and study of its reactivity. As a result, it is expected to provide new routes to produce robust and easy-to-process NCs in a wide range of sizes, shapes and configurations that can be explored to achieve the combination of all degrees of control, aiming to produce a complete and diverse library of material combinations that will expand its applicability in a wide diversity of fields.

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The adsorption of poly(vinyl alcohol) by natural soil aggregates

Soil Research ◽

10.1071/sr9660131 ◽

1966 ◽

Vol 4 (2) ◽

pp. 131 ◽

Cited By ~ 15

Author(s):

BG Williams ◽

DJ Greenland ◽

JP Quirk

Keyword(s):

Soil Aggregates ◽

Chemical Properties ◽

Poly Vinyl Alcohol ◽

Natural Soil ◽

Polymer Diffusion ◽

Physico Chemical ◽

Chemical Factors ◽

Soil Conditioners ◽

Natural Aggregates ◽

Physical And Chemical

The adsorption of poly(viny1 alcohol) by natural aggregates and undisturbed core samples of Urrbrae loam has been investigated. The factors studied included the size, shape, and structure of the polymer, the physico-chemical properties of the soil, and external physical and chemical factors. The rate of adsorption has been interpreted in terms of polymer diffusion in a porous medium and the significance of these studies in relation to the use of synthetic soil conditioners has been discussed.

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Relationship Among the Physico-Chemical Parameters of Soil and Water in Different Wetland Ecosystems

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22616 ◽

2020 ◽

Vol 32 (7) ◽

pp. 1681-1690

Author(s):

Bibhu Prasad Panda ◽

Manas Barik ◽

Biswajita Mahapatra ◽

Siba Prasad Parida ◽

Aditya Kishore Dash ◽

...

Keyword(s):

Research Work ◽

Chemical Properties ◽

Analytical Techniques ◽

Wetland Ecosystem ◽

Chemical Parameters ◽

Wetland Ecosystems ◽

Physico Chemical ◽

Chemical Factors ◽

Soil And Water

The quality of life in water bodies depends on their physico-chemical properties and biodiversity. These physico-chemical properties are being disturbed by continuous addition of industrial, municipal and agricultural wastes which make them unfit for different organisms. This study describes the physico-chemical factors in soil and water of all sampled wetlands and the relationship among them in wetland ecosystem. All these analysis were done by using analytical techniques as described by standard methods for examination of water and wastewater. Physico-chemical parameters of water and soil also interlinked and correlated among each other. Sometimes these parameters work as a cycle to maintain the equilibrium in the ecosystem. Higher level of research work is needed to control the source of pollution to wetlands. By controlling the physico-chemical parameters of habitat, the diversity, density and richness of various wetland dependent species can be controlled in wetland ecosystem.

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Monthly variation in physico-chemical properties of Kosi River in Almora district, Uttrakhand

Environment Conservation Journal ◽

10.36953/ecj.2014.151227 ◽

2014 ◽

Vol 15 (1&2) ◽

pp. 201-205

Author(s):

Pramod Kumar ◽

Hem Chandra Upadhyay ◽

Anupama Pandey

Keyword(s):

Monsoon Season ◽

Chemical Properties ◽

Total Alkalinity ◽

Strong Impact ◽

Monthly Variation ◽

Chemical Parameters ◽

Physico Chemical ◽

Free Carbon Dioxide ◽

Chemical Factors ◽

Total Dissolved Solid

The present investigation was carried out on the Kosi River, an important tributary of the river Ramgangafrom January 2012 to December 2012. Kosi is a spring fed river. The constituents monitored included water temperature, current velocity, pH, total dissolved solid, total solids, conductivity, dissolved oxygen, free carbon dioxide, total alkalinity and hardness. Throughout the study period, the water was found hard and a significant variation of the rest parameters were observed. The present study also revealed that the physico-chemical parameters showed a great seasonal variation and velocity of water andtotal solids were found to be highest in monsoon season that had a strong impact on other physico-chemical factors of the river.

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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PHYSICO CHEMICAL PROPERTIES OF NICKEL OXIDE AT HIGH TEMPERATURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976798 ◽

1976 ◽

Vol 37 (C7) ◽

pp. C7-438-C7-442 ◽

Cited By ~ 2

Author(s):

R. FARHI ◽

G. PETOT-ERVAS

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Chemical Properties ◽

Physico Chemical

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Physico-Chemical Properties of Recombinant Desulphatohirudin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645073 ◽

1990 ◽

Vol 63 (03) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

A Electricwala ◽

L Irons ◽

R Wait ◽

R J G Carr ◽

R J Ling ◽

...

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Chemical Properties ◽

Alpha Helix ◽

Apparent Molecular Weight ◽

Correlation Spectroscopy ◽

Nmr Studies ◽

Recombinant Hirudin ◽

Physico Chemical ◽

Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

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Characteristics Of The Structure Formation Of Gypsum Binder Modified With Zinc Hydrosilicates

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2020.02.40-46 ◽

2020 ◽

pp. 40-46

Keyword(s):

Synergistic Effect ◽

Physicochemical Properties ◽

Structure Formation ◽

Silicic Acid ◽

Chemical Properties ◽

Crystal Formation ◽

Ability To Act ◽

Chemical Factors ◽

Sorption Characteristics

The authors' methodic for assessing the role of chemical and physic-chemical factors during the structure formation of gypsum stone is presented in the article. The methodic is also makes it possible to reveal the synergistic effect and to determine the ranges of variation of controls factors that ensure maximum values of such effect. The effect of a micro-sized modifier based on zinc hydro-silicates on the structure formation of building gypsum is analyzed and corresponding dependencies are found. It is shown that effects of influence of modifier on the properties of gypsum compositions are determined by chemical properties of modifier. Among the mentioned properties are sorption characteristics (which depend on the amount of silicic acid and its state) and physicochemical properties - the ability to act as a substrate during crystal formation. The proposed method can also be extended to other binding substances and materials. This article contributes to the understanding of the processes that occur during the structure formation of composites, which will make it possible to control the structure formation in the future, obtaining materials with a given set of properties.

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