Chemical structure and sources of the macromolecular, resistant, organic fraction isolated from a forest soil (Lacadée, south-west France)

2000 ◽  
Vol 31 (9) ◽  
pp. 813-827 ◽  
Author(s):  
Natacha Poirier ◽  
Sylvie Derenne ◽  
Jean-Noël Rouzaud ◽  
Claude Largeau ◽  
André Mariotti ◽  
...  
2006 ◽  
Vol 76 (1-2) ◽  
pp. 271-279 ◽  
Author(s):  
K. Quénéa ◽  
S. Derenne ◽  
F.J. González-Vila ◽  
J.A. González-Pérez ◽  
A. Mariotti ◽  
...  

1996 ◽  
Vol 33 (9) ◽  
pp. 155-162 ◽  
Author(s):  
Jean-Luc Bertrand-Krajewski ◽  
Hervé Madiec ◽  
Olivier Moine

Specific sediment traps for solids transported as bed load during storm events could be an interesting alternative to usual grit chambers. Two field experiments have been carried out in Bordeaux (south-west of France) in 1993 and 1994 to characterise the solids caught in the traps and to assess the sediment trap efficiency. These two sites have been chosen because it was easy to transform the existing usual grit chambers with a set of boxes used as sediment traps. The mass of trapped solids is well correlated with the rainfall height, for rainfalls of less than 50 mm. For greater rainfalls, the experimental sediment traps were too small to catch all solids. The efficiency of the sediment traps located at the grit chamber inlet side is assessed at about 70-80% in mass. Only 20-30% of solids are trapped at the outlet side. The efficiency decreases rapidly for the traps that are not in alignment with the median axis of the inlet pipe. The grain size distribution of the trapped solids is very characteristic: the d10, d50 and d90 values decrease when the traps are farther away from the median axis of the inlet pipe. This distribution of the trapped solids is due to the enlargement of the grit chamber which leads to a decrease of the flow velocity. The organic fraction increases when the d50 decreases: the finer the particles, the more organic the fractions.


Author(s):  
Елена Исаева ◽  
Elena Isaeva ◽  
Ольга Педосич ◽  
Olga Pedosich

The article presents results of tests which have been done during the stationary experiment carried out in the South-West of Bryansk region of the Non-Chernozem zone of Russia on gray forest soil. The test object in 2015–2018 was to study methods of the main soil tillage and their effect on productivity of sweet oat. The test scheme consists of four variants of the main soil tillage at sweet oat cultivation in four-field lupin crop rotation. The variant earth board ploughing added by deep loosening once in four years for lupin stood out under the test period conditions. Sweet oat had high yield and nutritive value at this soil tillage. These indices were energetically profitable.


Author(s):  
J. Silcox

In this introductory paper, my primary concern will be in identifying and outlining the various types of inelastic processes resulting from the interaction of electrons with matter. Elastic processes are understood reasonably well at the present experimental level and can be regarded as giving information on spatial arrangements. We need not consider them here. Inelastic processes do contain information of considerable value which reflect the electronic and chemical structure of the sample. In combination with the spatial resolution of the electron microscope, a unique probe of materials is finally emerging (Hillier 1943, Watanabe 1955, Castaing and Henri 1962, Crewe 1966, Wittry, Ferrier and Cosslett 1969, Isaacson and Johnson 1975, Egerton, Rossouw and Whelan 1976, Kokubo and Iwatsuki 1976, Colliex, Cosslett, Leapman and Trebbia 1977). We first review some scattering terminology by way of background and to identify some of the more interesting and significant features of energy loss electrons and then go on to discuss examples of studies of the type of phenomena encountered. Finally we will comment on some of the experimental factors encountered.


Author(s):  
N.-H. Cho ◽  
K.M. Krishnan ◽  
D.B. Bogy

Diamond-like carbon (DLC) films have attracted much attention due to their useful properties and applications. These properties are quite variable depending on film preparation techniques and conditions, DLC is a metastable state formed from highly non-equilibrium phases during the condensation of ionized particles. The nature of the films is therefore strongly dependent on their particular chemical structures. In this study, electron energy loss spectroscopy (EELS) was used to investigate how the chemical bonding configurations of DLC films vary as a function of sputtering power densities. The electrical resistivity of the films was determined, and related to their chemical structure.DLC films with a thickness of about 300Å were prepared at 0.1, 1.1, 2.1, and 10.0 watts/cm2, respectively, on NaCl substrates by d.c. magnetron sputtering. EEL spectra were obtained from diamond, graphite, and the films using a JEOL 200 CX electron microscope operating at 200 kV. A Gatan parallel EEL spectrometer and a Kevex data aquisition system were used to analyze the energy distribution of transmitted electrons. The electrical resistivity of the films was measured by the four point probe method.


2019 ◽  
Vol 25 ◽  
pp. 317
Author(s):  
Ayotunde Ale ◽  
Opeyemi Aloro ◽  
Ayanbola Adepoju
Keyword(s):  

2019 ◽  
Vol 25 ◽  
pp. 121-122
Author(s):  
Olufunmilayo Adeleye ◽  
Ejiofor Ugwu ◽  
Anthonia Ogbera ◽  
Akinola Dada ◽  
Ibrahim Gezawa ◽  
...  

2016 ◽  
Vol 86 (3-4) ◽  
pp. 127-151 ◽  
Author(s):  
Zeshan Ali ◽  
Zhenbin Wang ◽  
Rai Muhammad Amir ◽  
Shoaib Younas ◽  
Asif Wali ◽  
...  

While the use of vinegar to fi ght against infections and other crucial conditions dates back to Hippocrates, recent research has found that vinegar consumption has a positive effect on biomarkers for diabetes, cancer, and heart diseases. Different types of vinegar have been used in the world during different time periods. Vinegar is produced by a fermentation process. Foods with a high content of carbohydrates are a good source of vinegar. Review of the results of different studies performed on vinegar components reveals that the daily use of these components has a healthy impact on the physiological and chemical structure of the human body. During the era of Hippocrates, people used vinegar as a medicine to treat wounds, which means that vinegar is one of the ancient foods used as folk medicine. The purpose of the current review paper is to provide a detailed summary of the outcome of previous studies emphasizing the role of vinegar in treatment of different diseases both in acute and chronic conditions, its in vivo mechanism and the active role of different bacteria.


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