scholarly journals Mechanical Destruction of Weeds: A Review

2009 ◽  
pp. 399-410 ◽  
Author(s):  
D. Chicouene
Keyword(s):  
Mechanical Destruction

An electron microscopic study of the intra-myocardial lesions in cases of acute myocardial infarction

1978 ◽  
Vol 36 (2) ◽  
pp. 484-485
Author(s):  
Masahiro Ono ◽  
Kaoru Aihara ◽  
Gompachi Yajima
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Coronary Vessels ◽  
Vascular Wall ◽  
Vascular Changes ◽  
Electron Microscopic ◽  
Main Trunk ◽  
Mechanical Destruction ◽  
Transmission Electron ◽  
Myocardial Lesions

The pathogenesis of the arteriosclerosis in the acute myocardial infarction is the matter of the extensive survey with the transmission electron microscopy in experimental and clinical materials. In the previous communication,the authors have clarified that the two types of the coronary vascular changes could exist. The first category is the case in which we had failed to observe no occlusive changes of the coronary vessels which eventually form the myocardial infarction. The next category is the case in which occlusive -thrombotic changes are observed in which the myocardial infarction will be taken placed as the final event. The authors incline to designate the former category as the non-occlusive-non thrombotic lesions. The most important findings in both cases are the “mechanical destruction of the vascular wall and imbibition of the serous component” which are most frequently observed at the proximal portion of the coronary main trunk.

Electron Paramagnetic Resonance of Radicals Formed during Milling

1960 ◽  
Vol 33 (2) ◽  
pp. 462-468 ◽  
Author(s):  
S. E. Bresler ◽  
S. N. Zhurkov ◽  
E. N. Kazbekov ◽  
E. M. Saminskiĭ ◽  
E. E. Tomashevskiĭ
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Gamma Rays ◽  
Epr Spectra ◽  
Mechanical Degradation ◽  
Present Communication ◽  
Surface Layers ◽  
Paramagnetic Resonance ◽  
Mechanical Destruction ◽  
Electron Paramagnetic

Abstract It is well known that during the mechanical degradation of polymers there takes place scission of molecular chains and the formation of macroradicals. It is of considerable interest to study the electron paramagnetic resonance (EPR) spectra of the macroradicals produced by milling, and to compare them with the spectra of the macroradicals formed in the process of polymerization, and also during the irradiation of polymers by gamma rays and neutrons. We may endeavor to compare the amount of macroradicals formed with the extent of mechanical destruction (for instance with the area of the new interface which is formed). In addition, as was found by experience, the macroradicals formed by mechanical scission are good models for the investigation of reactivity since practically all of them are in the newly formed surface layers and are therefore very accessible to various chemical influences. They enter easily into reaction with various agents present in the medium since in this process diffusion from the surface is found in practice not to be a predominating factor. In the present communication we give the first EPR results obtained on mechanically degraded polymers.

The Chemistry of the Active Molecules Formed in the Mechanical Degradation of Polymers

1957 ◽  
Vol 30 (4) ◽  
pp. 1162-1165
Author(s):  
A. A. Berlin
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Polyvinyl Acetate ◽  
Covalent Bond ◽  
Ultrasonic Waves ◽  
Mechanical Degradation ◽  
Specific Viscosity ◽  
Mechanical Destruction ◽  
Fluid State ◽  
Polymeric Chains

Abstract At the present time there is a multitude of data indicating that when polystyrene, natural rubber, polyvinyl acetate, cellulose, starch, proteins and other high molecular weight compounds are mechanically ground up, a degradation of the polymeric chains is observed. The mechanical scission of macromolecules during grinding in a colloid or ball mill, or when they are broken down on mill rolls, proceeds most rapidly at temperatures below the range of the viscous-fluid state, since under these conditions the forces of intermolecular interaction are considerably greater than the strength of the covalent bond. However, the mechanical destruction of macromolecules is also possible through certain mechanical effects acting on solutions of polymers. Thus, for instance, the force of friction generated in the flow of a 0.05% solution of polystyrene (Mcp=6×105) in tetralin through a platinum capillary is due to the scission of macromolecules, which brings about a 30% decrease in the specific viscosity. The significant gradients in the rate and in the forces of friction and cavitation developed in polymer solution through the action of ultrasonic waves with frequencies of the order of 200–300 kilocycles/sec. are due to the mechanical scission of macromolecules of polystyrene, rubber, polyvinyl acetate, cellulose and a number of other high molecular weight compounds.

Experimental investigation into mechanical destruction of intumescent chars

2000 ◽  
Vol 11 (8-12) ◽  
pp. 392-397 ◽  
Author(s):  
Igor S. Reshetnikov ◽  
Anatoly N. Garashchenko ◽  
Valery L. Strakhov
Keyword(s):  
Experimental Investigation ◽  
Mechanical Destruction

scholarly journals The Mechanical Destruction of Bacteria

1948 ◽  
Vol 2 (3) ◽  
pp. 315-324 ◽  
Author(s):  
H. K. King ◽  
H. Alexander
Keyword(s):  
Mechanical Destruction

The mechanisms of the mechanical destruction of polymers in bulk

1977 ◽  
Vol 19 (1) ◽  
pp. 100-110 ◽  
Author(s):  
G.B. Manelis ◽  
L.P. Smirnov ◽  
Ye.V. Polianchik ◽  
S.N. Bloshenko
Keyword(s):  
Mechanical Destruction

scholarly journals 3D Photogrammetry Modeling Highlights Efficient Reserve Effect Apparition After 5 Years and Stillness After 40 for Red Coral (Corallium rubrum) Conservation in French MPAs

2021 ◽  
Vol 8 ◽  
Author(s):  
Justine Richaume ◽  
Adrien Cheminée ◽  
Pierre Drap ◽  
Patrick Bonhomme ◽  
Frederic Cadene ◽  
...  
Keyword(s):  
National Park ◽  
Local Level ◽  
Cost Effective ◽  
Maximum Height ◽  
Time Step ◽  
Mechanical Destruction ◽  
Corallium Rubrum ◽  
Red Coral ◽  
Significant Difference ◽  
Precautionary Measures

Imaging the marine environment is more and more useful to understand relationships between species, as well as natural processes. Developing photogrammetry allowed the use of 3D measuring to study populations dynamics of sessile organisms at various scales: from colony to population. This study focuses on red coral (Corallium rubrum), as known as precious coral. Metrics measured at a colony scale (e.g., maximum height, diameter and number of branches) allowed population understanding and a comparison between an old (Cerbère-Banyuls reserve) vs. a new (Calanques National Park) MPA. Our results suggested a 5-year time step allows the appearance of a significant difference between populations inside vs. outside the Calanques National Park no-take zones. Red coral colonies were taller and had more branches inside no-take zones. A significant difference was still observable for the populations inside the Cerbère-Banyuls reserve after 40 years of protection, reflecting the sustainability and effectiveness of precautionary measures set by the reserve. The impacts at the local level (mechanical destruction) and those presumed to occur via global change (climatic variations) underline the need to develop strategies both to follow the evolutions of red coral populations but also to understand their resilience. Photogrammetry induced modeling is a time and cost effective as well as non-invasive method which could be used to understand population dynamics at a seascape scale on coralligenous reefs.

scholarly journals Integration of Stalk Destruction Methods for the Glyphosate Herbicide-Resistant Cotton

2022 ◽  
Vol 10 (2) ◽  
pp. 1
Author(s):  
Valdinei Sofiatti ◽  
Odilon RRF Silva ◽  
Edson R Andrade Junior ◽  
Alexandre CB Ferreira ◽  
Fabiano J Perina ◽  
...  
Keyword(s):  
Plant Pathogens ◽  
Cotton Stalk ◽  
Chemical Methods ◽  
Mechanical Destruction ◽  
Mato Grosso ◽  
Herbicide Resistant ◽  
Control Efficiency ◽  
Cotton Stalks ◽  
Chemical Destruction ◽  
Glyphosate Herbicide

The increase in geographical areas used for cultivation of transgenic glyphosate herbicide-resistant cotton has hindered the stalk destruction, compromised the phytosanitary break implementation and consequently increased the population of insect pests and cotton plant pathogens. This study evaluated the efficiency of the combining mechanical and chemical methods in the destruction of transgenic cotton stalk resistant to the glyphosate herbicide. Two experiments were carried out in 2015 and 2016 in Primavera do Leste,-Mato Grosso, Brazil and Luís Eduardo Magalhães, Bahia, Brazil, respectively. The study evaluated different mechanical destruction equipment in combination with the chemical methods. In each environment, a randomized block experiment with four replications was employed. The results of the experiments indicated that the mechanical destruction increased the control efficiency by at least 10% when compared to chemical destruction of the cotton stalk. Chemical destruction with herbicides combined with mechanical destruction methods does not increase the control efficiency of cotton stalks destruction. Furthermore, the application of hormonal herbicides following the mechanical shredding of cotton stalks does not increase the control efficiency of glyphosate-resistant cotton stalk.

scholarly journals Evaluation of cotton stalks destroyers

2013 ◽  
Vol 33 (5) ◽  
pp. 965-975 ◽  
Author(s):  
Aloisio Bianchini ◽  
Pedro H. de M. Borges
Keyword(s):  
Soil Type ◽  
Energy Demand ◽  
Crop Residues ◽  
Clay Soil ◽  
Field Capacity ◽  
Soil Types ◽  
Mechanical Destruction ◽  
Cotton Crop ◽  
Cotton Stalks ◽  
Medium Texture

The destruction of the cotton crop residues (cotton stalks) is a mandatory procedure in Brazil for prophylactic issues, but is a subject unexplored by the research and there are few studies that deal with this issue. However, this is not encouraged in recent decades, studies aimed at developing and evaluating equipment for this purpose. The present study had the objective to evaluate six methods for mechanical destruction of cotton crop residues. Each method was defined based on the principle of operation of the active parts of the equipment, which were tested in medium texture soil and in a clayey one. The variables used to evaluate the efficiency of the equipment were the regrowth rate, the theoretical field capacity and energy demand. The equipment with convergent concave disks (DCC) and flat cutters discs from manufacturer A (CPS-a) showed the best results in cotton stalks destruction in both soil types. The harrow disc (GPD) was efficient only in clay soil. It was concluded that the equipment with convergent concave disks, among those tested, was the most efficient to destroy cotton stalks, regardless of soil type, and that the harrow disc was not included among the best performers.

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