Utilisation de vecteurs tournants pour l'optimisation de la formulation de mélanges de solvants

2002 ◽  
Vol 80 (4) ◽  
pp. 350-361
Author(s):  
Serge Alex
Keyword(s):  
Chemical Composition ◽  
Physical Properties ◽  
Visual Analysis ◽  
Chemical Properties ◽  
New Strategy ◽  
Halogenated Solvents ◽  
Solvent Blends ◽  
The Individual ◽  
Physical And Chemical ◽  
And Chemical Properties

A new strategy is proposed to optimize the design of solvent blends without using complex mathematical models and (or) graphical representations. All calculations are made with standard electronic programs, such as Excel, Lotus, etc. This approach was developed for the cleaning and degreasing industry, which has to find new recipes of solvent blends on a regular basis. The process relies on a visual analysis of the sum of normalized rotating vectors associated with the chemical composition and the physical properties of the individual components. This approach allows for representation of all parameters on a two-dimensional plot, including information about chemical composition, as well as the physical properties to be optimized. The research of a new mixture of halogenated solvents will be used as an example to illustrate the various steps of this technique. This method is not limited to solvent applications; it also applies to all problems that involve comparisons of physical and chemical properties of blends.Key words: solvents, mixtures, components, optimization, cleaning.

scholarly journals Anatomical characterization, physical, and chemical properties of wood of Quercus macdougallii Martínez, endemic species of the Sierra Juárez of Oaxaca, Mexico

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 5975-5998
Author(s):  
Faustino Ruiz-Aquino ◽  
Lizbeth Luna-Bautista ◽  
Aremi E. Luna-Bautista ◽  
Wenceslao Santiago-García ◽  
Luis F. Pintor-Ibarra ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Physical Properties ◽  
Endemic Species ◽  
Basic Density ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Cellulose Pulp ◽  
Physical And Chemical ◽  
First Time ◽  
And Chemical Properties

The anatomical characteristics and the physical and chemical properties of wood of Quercus macdougallii Martínez are presented for the first time. Q. macdougallii Martínez is an endemic species of the Sierra Juarez of Oaxaca. The microscopic characteristics were described in preparations of typical cuts and dissociated material. The physical properties were evaluated according to the ASTM D 143-94 standard in sapwood and heartwood specimens. The measurable elements and physical properties were classified according to the mean. With the measurable elements, the paper pulp quality index was determined. In sapwood and heartwood, the basic chemical composition was determined. The wood of Q. macdougallii presented a pronounced grain, a thick texture, and a straight thread. Fibers, fibrotracheids, uniseriate, multiseriate, and aggregate rays were found. Basic density 0.55 g cm-3 in sapwood and 0.61 g cm-3 in heartwood is classified as moderately heavy and heavy, respectively. The saturation point of the fiber is classified as high. Based on its physical properties, Q. macdougallii wood can be used in the manufacture of furniture, veneer, floors, tool handles, and construction. Based on the pulp quality indices and chemical composition, this wood could be used to obtain cellulose pulp for paper.

scholarly journals VARIABILITY OF PHYSICAL AND CHEMICAL PROPERTIES OF MAGNETITE AND QUARTZ OF THE NORTHERN DESTRICT OF KRYVYI RIH BASIN

2021 ◽  
pp. 17-23
Author(s):  
S. Tikhlivets
Keyword(s):  
Chemical Composition ◽  
Physical Properties ◽  
Iron Ore ◽  
Chemical Properties ◽  
Ore Deposits ◽  
Low Grade ◽  
Physical And Chemical Properties ◽  
Iron Ore Deposits ◽  
Physical And Chemical ◽  
And Chemical Properties

Physical properties of minerals represent a function of their chemical composition, features of morphology and anatomy. Their variability is influenced by geological syngenetic and epigenetic processes that occur within the iron ore deposits of Kryvyi Rih basin. The latter is represented by nine deposits, which are exploited by five ore mining and enrichment works (GZKs). The Northern region of Kryvyi Rih basin includes Hannivske and Pervomayske deposits. The productive strata of both deposits consist of low-grade magnetite ores of the fifth and sixth ferruginous horizons. They are characterized by the authigenic-metamorphogenic mineralogical zonation. The purpose of the work is conditioned by the need for a detailed study of the laws of variability of chemical composition and physical properties of rock-forming minerals (magnetite and quartz), taking into account their position within zonal ore deposits. The study of the physical properties of rock-forming minerals was carried out according to standard methods using a microhardness tester, the chemical composition was investigated by segregating monomineral fractions of magnetite and quartz from ores of metamorphic or metasomatic origins of various mineral composition using a magnetic separator. The chemical analyzes were carried out in a standardized chemical laboratory. Statistical studies were performed using Excel software and Corel Draw. Result of the researches showed the nature of variability of the chemical composition, physical properties of magnetite and quartz in the sections of metamorphogenic and metasomatically altered ore strata of iron ore deposits. Practical significance is conditioned by the necessity of conducting detailed topomineralogical study of the productive strata of iron ore deposits of Kryvyi Rih basin in relation to the work on updating the mineralogical and technological map of the deposit, compiling an optimal scheme for ore blending in order to increase efficiency of the use of natural technological potential of magnetite quartzites on the basis of studying physical and chemical properties of the main rock-forming minerals of ferruginous quartzite.

scholarly journals Chemical and Physical Properties of Some Hazelnut Varieties Grown in Portugal

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1476
Author(s):  
Ana Cristina Ferrão ◽  
Raquel P. F. Guiné ◽  
Elsa Ramalhosa ◽  
Arminda Lopes ◽  
Cláudia Rodrigues ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Physical Properties ◽  
Water Activity ◽  
Induction Time ◽  
Oxidation Stability ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Nutritional Characteristics ◽  
Physical And Chemical ◽  
And Chemical Properties

Hazelnuts are one of the most appreciated nuts worldwide due to their unique organoleptic and nutritional characteristics. The present work intended to analyse several physical and chemical properties of different hazelnut varieties grown in Portugal, namely Tonda de Giffoni, Grada de Viseu, Segorbe, Longa de Espanha, Butler, Gunslebert, and Negreta. In general, the results revealed statistically significant differences between the varieties under study. The Gunslebert had more elongated hazelnuts and with heavier shelled fruits, while the kernels of the Grada de Viseu revealed to be heavier. Grada de Viseu was harder in the shell, Gunslebert had a harder core, and Segorbe was more resistant to fracture. Fat was the more representative component for all varieties and in some cases the values of moisture and water activity were over the recommended amount (≥0.62). Tonda de Giffoni was the variety with the highest induction time, indicating the highest oxidation stability. Moreover, discriminant analysis revealed that the variables more important to distinguish the varieties were protein (λ = 0.007) and water activity (λ = 0.010). The results of this study help to better understand the differences between some hazelnut varieties that are cultivated in Portugal, which gives important hints for all players in the hazelnut sector.

scholarly journals Effect of Mosses on physical and chemical properties of soil in temperate forests of Garhwal Himalayas

2021 ◽  
pp. 1-10
Author(s):  
Anshu Siwach ◽  
Siddhartha Kaushal ◽  
Ratul Baishya
Keyword(s):  
Physical Properties ◽  
Chemical Properties ◽  
Nutrient Status ◽  
High Rate ◽  
Physical And Chemical Properties ◽  
Garhwal Himalayas ◽  
Forest Sites ◽  
Significant Difference ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Mosses are one of the most important and dominant plant communities, especially in the temperate biome, and play a significant role in ecosystem function and dynamics. They influence the water, energy and element cycle due to their unique ecology and physiology. The present study was undertaken in three different temperate forest sites in the Garhwal Himalayas, viz., Triyuginarayan (Kedarnath Wildlife Sanctuary (KWLS)), Chakrata, and Kanasar forest range. The study was focused on understanding the influence of mosses on soil physical properties and nutrient availability. Different physico-chemical properties were analysed under two different substrata, that is, with and without moss cover in two different seasons, viz., monsoon and winter. We observed mosses to influence and alter the physical properties and nutrient status of soil in both seasons. All soil physical and chemical properties, except magnesium, showed significant difference within the substrates, among all the sites and across the two seasons. Besides the soil characteristics underneath the moss vegetation, the study also highlights the diversity of mosses found in the area. Mosses appear to create high nutrient microsites via a high rate of organic matter accumulation and retain nutrients for longer periods thus, maintaining ecosystem stability.

Study of Relative Metallic Character of Noble Metals Cu, Ag and Au at Normal Temperatures

2021 ◽  
Vol 1019 ◽  
pp. 174-178
Author(s):  
Ramesh Kumar ◽  
Priti Kumari ◽  
Kumar Saurav ◽  
Purushottam Poddar ◽  
Vijay Kumar Verma
Keyword(s):  
Physical Properties ◽  
Noble Metals ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Metallic Character ◽  
Physical And Chemical ◽  
And Chemical Properties

The relative metallic character of noble metals, Cu, Ag & Au has been suggested by their physical and chemical properties. Their position in the metallic series is in the neighborhood of that of Li, Mg and Zn. These Metals are inferior of Li, Mg, Zn, Fe, Co and Ni in metallic character. Li, Mg, Zn, Fe, Co and Ni are inferior to Na, K, Rb, Cs, Ca, Ba and Sr. The noble metals have simple metallic character in physical properties at normal temperatures.

scholarly journals Study of Heavy Metals in the Soils of Two Localities in Dolj County

2018 ◽  
Vol 1 (1) ◽  
pp. 352-357
Author(s):  
Gilda-Diana Buzatu ◽  
Ana Maria Dodocioiu
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Wastewater Treatment ◽  
Chemical Composition ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Chemical Properties ◽  
Chemical Parameters ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract The study was conducted in two neighboring localities located in the northern county of Dolj, namely Murgasi and Bulzesti. The purpose of the study was twofold: namely, the study of heavy metal loading in order to identify possible pollution areas and to know the soil content of these localities in heavy metals in order to be able to give the verdict on the use of sludge from Craiova wastewater treatment plant as fertilizer on these soils. In order to determine the suitability of sewage sludge from the Craiova wastewater treatment plant as a fertilizer, physical and chemical properties and heavy metal content of the soils in these areas were analysed, as well as the chemical composition of sludge, according to Order 344/2004 of the Ministry of Environment and Water Management of Romania, respectively 13 physical and chemical parameters of the soils in these localities and the chemical composition of the sludge and respectively the quantity of heavy metals to be introduced annually into the soil by using it.

scholarly journals In-situ Detection Method for Microplastics in Water by Polarized Light Scattering

2021 ◽  
Vol 8 ◽  
Author(s):  
Tong Liu ◽  
Shijun Yu ◽  
Xiaoshan Zhu ◽  
Ran Liao ◽  
Zepeng Zhuo ◽  
...  
Keyword(s):  
Light Scattering ◽  
Scattered Light ◽  
Polarized Light ◽  
Chemical Properties ◽  
Future Application ◽  
Physical And Chemical Properties ◽  
The Individual ◽  
Physical And Chemical ◽  
And Chemical Properties

Microplastics (MPs) have become the widespread contaminants, which raises concerns on their ecological hazards. In-situ detection of MP in water bodies is essential for clear assessment of the ecological risks of MPs. The present study proposes a method based on polarized light scattering which measures the polarization parameters of the scattered light at 120° to detect MP in water. This method takes the advantage of in-situ measurement of the individual particles and the experimental setup in principle is used. By use of the measured polarization parameters equipped by machine learning, the standard polystyrene (PS) spheres, natural water sample, and lab-cultured microalgae are explicitly discriminated, and MP with different physical and chemical properties can be differentiated. It can also characterize the weathering of different MP and identify the specific type from multiple types of MP. This study explores the capability of the proposed method to detect the physical and chemical properties, weathering state and concentration of MP in water which promises the future application in water quality sensing and monitoring.

Corrigenda - The effects of minimum cultivation after three years on some physical and chemical properties of a red-brown earth at Forbes, NSW.

Soil Research ◽  
1991 ◽  
Vol 29 (2) ◽  
pp. 263 ◽  
Author(s):  
PP Cavanagh ◽  
AJ Koppi ◽  
AB Mcbratney
Keyword(s):  
Organic Carbon ◽  
Physical Properties ◽  
Bulk Density ◽  
Total Nitrogen ◽  
Chemical Properties ◽  
Water Infiltration ◽  
Electrolytic Conductivity ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Reducing cultivation may improve many soil physical and chemical properties of a red-brown earth. A trial was set up in 1986 on a red-brown earth near Forbes, N.S.W., comparing direct-drilling and conventional-cultivation crop establishment techniques. The surface soil (0-100 mm) was sampled at the end of the third year and assessed for macropore structure, infiltration characteristics, bulk density, pH, electrolytic conductivity, organic carbon and total nitrogen content. Cultivation degraded some desirable soil physical properties as indicated by data obtained from image analysis and infiltration. Bulk density did not mirror differences in macroporosity. Organic carbon, total nitrogen and electrolytic conductivity levels were higher in direct-drilled soil in comparison to conventionally tilled soil. It ib concluded that the improvement of soil chemical and physical properties afforded by a reduction in tillage would lead to an increase in soil water infiltration rate and storage.

The effects of minimum cultivation after three years on some physical and chemical properties of a red-brown earth at Forbes, NSW.

Soil Research ◽  
1991 ◽  
Vol 29 (2) ◽  
pp. 263
Author(s):  
PP Cavanagh ◽  
AJ Koppi ◽  
AB Mcbratney
Keyword(s):  
Organic Carbon ◽  
Physical Properties ◽  
Bulk Density ◽  
Total Nitrogen ◽  
Chemical Properties ◽  
Water Infiltration ◽  
Electrolytic Conductivity ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Reducing cultivation may improve many soil physical and chemical properties of a red-brown earth. A trial was set up in 1986 on a red-brown earth near Forbes, N.S.W., comparing direct-drilling and conventional-cultivation crop establishment techniques. The surface soil (0-100 mm) was sampled at the end of the third year and assessed for macropore structure, infiltration characteristics, bulk density, pH, electrolytic conductivity, organic carbon and total nitrogen content. Cultivation degraded some desirable soil physical properties as indicated by data obtained from image analysis and infiltration. Bulk density did not mirror differences in macroporosity. Organic carbon, total nitrogen and electrolytic conductivity levels were higher in direct-drilled soil in comparison to conventionally tilled soil. It ib concluded that the improvement of soil chemical and physical properties afforded by a reduction in tillage would lead to an increase in soil water infiltration rate and storage.

Study of the Chemical and Physical Properties of the Fiber-Matrix Interface of Biocomposite Material Based on a Copolymer Matrix Polylactic Acid (PLA)

2019 ◽  
Vol 12 (1) ◽  
pp. 70-78
Author(s):  
Mokhtaria Ould Kada ◽  
Allel Mokaddem ◽  
Bendouma Doumi ◽  
Mohamed Berber ◽  
Lahouari Temimi ◽  
...  
Keyword(s):  
Physical Properties ◽  
Polylactic Acid ◽  
Probabilistic Approach ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Matrix Interface ◽  
Fiber Matrix Interface ◽  
Fiber Matrix ◽  
Physical And Chemical ◽  
And Chemical Properties

Background: In this paper, we have studied the improvement of the physical and chemical properties of the fiber-matrix interface of a Biocomposite based on the copolymer polylactic acid (PLA). Methodology: We have developed an analytical model using a genetic approach to locate the interface damage under the effect of mechanical stress, temperature and humidity. Our simulation is based on Weibull's probabilistic approach and the law of water diffusion in polymer matrix, the diffusion is generated by Fick's law. Results: Our results show that the interface of Biocomposite (Starch-PLA) is the most resistant to the different constraints applied and that the physical and chemical properties of this material are much more improved compared to other materials studied by the same genetic model. Conclusion: Our calculations coincide perfectly with the conclusions of Antoine et al. who determined that natural fibers improve the physical properties of composite materials.

Sign in / Sign up

Export Citation Format

Share Document