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The purpose of this paper is to study the susceptibility to corrosion processes of X60, X65 and X70 steels immersed in sand-clay soil with pH 3.0, using electrochemical techniques, scanning electron microscopy (SEM), energy dispersive spectroscopy and X-ray diffraction (XRD).

Natural acidic soil sample was collected as close as possible to buried pipes (1.2 m in depth) in a Right of Way from south of Mexico. Both steels and soil were characterized through SEM and XRD. Then, open circuit potential was recorded for all steels exposed to soil at different exposure times. Thus, the electrochemical impedance spectroscopy (EIS) was traced, and anodic polarization curves were obtained.

The steel corrosion processes started when the active sites were exposed to natural acidic soil. However, corrosion rates decreased for three steels as immersion time increased, obtaining the highest corrosion rate for X60 steel (0.46 mm/year for 5 h). This behavior could be attributed to corrosion products obtained at different exposure times. While, 5 h after removing corrosion products, X65 steel was more susceptible to corrosion (1.29 mm/year), which was corroborated with EIS analysis. Thus, corrosion products for the three steels exposed to natural acidic soil depended on different microstructures, percentage of pearlite and ferrite phases, in which different corrosion processes could occur. Therefore, the active sites for carbon steel surfaces could be passivated with corrosion products.

The paper identifies the any implication for the research.

Some anodic peaks could be caused by metallic dissolution and was recorded using high positive polarization (high field of perturbation). In addition, the inductive effects and diffusion process were interpreted at low frequency ranges using EIS. According to X-ray diffraction (XRD), acidic soil had Muscovite containing aluminum and iron phases that were able to generate hydrogen proton at the presence of water; it might be promoted at the beginning of deterioration on low carbon steels. Steel surface cleaning after removing corrosion products was considered to study the possible diffusion phenomena on damaged steel surfaces using EIS.

The purpose of this paper is to study the corrosion behavior of Q235 steel in saturated acidic red and yellow soils.

The corrosion behavior of Q235 steel in saturated red and yellow soils was compared by weight-loss, SEM/EDS, 3D ultra-depth microscopy and electrochemical measurements.

R_p of the steel gradually increases and i_corr gradually decreases in both the red and yellow soils with time. The R_p of the steel in the red soil is lower, but its i_corr is higher than that in the yellow soil. The uniform corrosion rate, diameter and density of the corrosion pit on the steel surface in the red soil are greater than those in the yellow soil. Lower pH, higher contents of corrosive anions and high-valence Fe oxides in the red soil are responsible for its higher corrosion rates and local corrosion susceptibility.

This paper investigates the difference in corrosion behavior of carbon steel in saturated acidic red and yellow soils, which can help to understand the mechanism of soil corrosion.

Stoneware is probably the oldest, or one of the oldest, engineering materials. Two thousand years ago the Romans were using it for water conduits, and the wonderfully preserved pipes that still exist from those days show how imperishable the material is. In this article Dr. Singer examines the reasons for the success of stoneware drainpipes and compares the material with others sometimes used for this purpose. He concludes that no other material yet approaches stoneware for reliability.

Introduction Although the soil as a corrosive environment is probably of greater complexity than any other environment, it is possible to make some generalisations regarding soil types and corrosion. It is necessary to emphasise that corrosion in soils is extremely variable and can range from the rapid to the negligible. This can be illustrated by the fact that buried pipes have become perforated within one year, while archaeological specimens of ancient iron have probably remained in the soil for hundreds of years without significant attack.

The purpose of this paper is to show impacts of household wastes handling on some physicochemical parameters of surface water, soil, sediments and borehole water samples in Port Harcourt. Waste generated from the households are indiscriminately dumped on roads, stream channels, bush lands and open spaces thus defacing the landscape of the city, flooding and spreading vector-borne diseases. As a result there is unsustainable and wasteful utilisation of resources which gives rise to pollution of the environment. The research determines the pollution profile of some dumpsites, surface water bodies that act as recipients of household waste from result of analysis of physicochemical parameters.

Major dumpsites in the city were selected for sampling. Three sampling stations at upstream, discharge point and downstream were selected for water and sediments. Water samples were collected in one-litre plastic containers, and then labelled and transported to laboratory for analysis. Sediment samples were collected at a depth of 5-10 m under water and preservation, handling and analysis were based on standard principles and procedures. Soil samples were dug with auger at both top (0-15 cm) and bottom (15-30 cm) in radial coordinates. The soil and sediment samples were first digested using the wet oxidation method before analysis with atomic absorption spectrophotometry.

The physicochemical analysis of surface water samples showed that conductivity, salinity, turbidity, sulphate, phosphate, magnesium, total hardness and lead exceeded the World Health Organization and Nigerian Industrial Standard limits for drinking water qualities at the sampled areas. The same parameters in addition to pH and manganese also exceeded the limits for sediment samples. The soil pH showed acidity at the sampling stations for both top and bottom depths. Conductivity, sulphate, iron, manganese, phosphate and lead also exceeded the FMEnv Guidelines and standards for soil quality. The continuous discharge of household wastes on water and soil resulted in elevated levels of some measured parameters.

The research was limited by funds. The cost of sampling and analysis was enormous and limited the study to parameters that available funds could carry. This factor also stretched the period of study. The non-availability of sponsorship made it difficult to extend the research to soil particle size distribution and the underground water movement of the study areas. Another limitation was logistics as the study covered vast areas of the metropolis demanding steady means of mobility that was not available. Epileptic supply of power delayed the timely delivery of result of analysis.

The results of the analysed physicochemical parameters of water, sediments, soil and borehole water samples indicated spatial variations in their values at the study area, with higher values at the discharge points and downstream than the upstream, while for the borehole water analysis, the effect was more pronounced at stations with appreciable quantity of degradable household wastes. The levels of some physicochemical variables exceeded standard limits as a result of continuous discharge of household wastes .The implication is that household waste handling influenced the physicochemical variables negatively and constant monitoring serves as a useful tool of abatement.

This work is original and has not been published before in any book or journal article locally or internationally. The research related waste handling lifestyles with concentrations of measurable parameters, which is an additional work to what other authors have done. The value is that data generated will be a reference material to other researchers, city planners, government agencies and institutions that are involved with environmental management. Furthermore it has added a new dimension to the discipline of waste management in terms of scope and contribution to knowledge.

The purpose of this paper is to study bio‐safe technology – impact of rhizospheric bacteria Azotobacter and Bacillus within the composition of environmentally clean complex microbiological biofertilizer “BioWais” prepared on the basis of nitrogen‐, phospho‐ and silicon‐bacterin on physiological parameters of plants: growth, productivity, the role of rhizobacteria in plants resistance to biotic and abiotic factors.

The following contemporary methods of investigation of physiological parameters of biological objects: immunoenzyme analysis of phytohormones, method of combinatory light dissemination, determination of amino acid composition of grain proteins by ion‐exchange chromatography, spectrophotometric methods were used.

The positive impact of biofertilizer “BioWais” on plant growth and development, enhancement of resistance of bacterized plants to hypothermia and pathogenic infection, increase of carotid content were demonstrated.

The bacteria under study biopreparation were shown to act as plant growth‐promoting rhizobacteria foster increase of plant anti‐oxidant protection, adaptation of seedlings to hypothermia, synthesize cytokinins and indolyl acetic acid.

Bacterial preparation increases quality and amount of agricultures yield, it may be recommended to treat seeds prior to planting with the view to stimulate germination, to enhance plants resistance to hypothermia and fungus‐induced diseases, for improvement of plant growth and development.

New, innovative, environmentally pure bacterial preparation BioWais showed significant efficiency for a number of agrocultures and may be used for acquisition of safe plant products of high quality (with high content of protein, essential amino acids and carotin, potential source of vitamin A, low content of nitrates).

Vehicular road traffic may represent an important soil and plant contamination source. In this context, the concentration of heavy metals (Cd, Pb, As, Sb, Ni, Cu, Fe, Al, Mn and Zn) and macronutrients (Ca, Mg, K and P) was evaluated in yerba mate (Ilex paraguariensis St. Hil.) cultivations and in soils adjacent to highways.

The investigated yerba mate cultivations were located in southern Brazil. Plant tissue (young and old leaves and branches) and soil (0–10 cm) samples were collected at five distances from the highway (0–10, 10–20, 20–30, 30–40 and 40–50 m). Plant tissue was analyzed with and without washing to evaluate contributions from particulate deposition.

Although increases in soil pseudo-total concentrations of Cd, Cu, Ni, Zn, Fe, Mn, Ca and Mg were observed only at the Erechim site, geoaccumulation indices and enrichment factors (EFs) did not indicate any heavy metal pollution. These results indicate the existence of natural variation in soil. Cadmium was more concentrated in branches than in leaves, while the opposite was observed for Pb. High levels of Mn and Al were found in foliar tissue. In summary, highway proximity did not lead to heavy metal contamination of yerba mate under the evaluated conditions.

This research explores the possibility of heavy metal pollution in plantations of yerba mate adjacent to highways and indicates natural concentrations of toxic elements that exceed current legislation, which was an important discovery regarding the yerba mate production chain.

To expose the gate of ion‐sensitive field‐effect transistor (ISFET) to filthy and muddy water, suspended algae, etc. investigate the influence of these conditions on device performance and suggest measures for using the device in applications where suspended soil particles are present.

In this paper, cleaning procedure to make the blocked ISFET operative has been described. The effect of dirty water on pH sensitivity factor of ISFET, after it restarted functioning, has been measured. ISFET package has been modified. A relatively simple disposable nylon mesh with openings of size 100 μm for filtering bigger particles and lower for smaller particles, has been proposed for dirty applications to minimize device failures. This sieves away any dirt and thereby avoids failure.

The device action is frequently blocked by deposition of dirt on the gate. Generally, it is recoverable by proper cleaning action although with reduced sensitivity. This necessitates recalibration. But a protective filter helps in reducing failures. It is more advantageous to prevent clogging of ISFET than to revive a clogged device, sacrificing sensitivity.

After recovery, the original sensitivity of the device is not achieved, and the device has to be used with degraded sensitivity.

Measurement of pH of actual sources of water, whether clean or dirty, is important.

Problems of pH measurements of dirty samples have been studied. The study helps in understanding device behaviour in these samples and provides suitable corrective measures. Further, the pH survey of dirty and clean water samples provides useful information about the pH distribution and balance in nature.

The purpose of this paper was to study the corrosion process of API X52, X60, X65, X70 and X80 steels exposed to two clay soils collected in two states of Mexico (Tabasco and Campeche). To saturate the soils, 60 mL of deionized water was added to simulate the conditions for dry and wet season, due to in field, the climate change could modifies the physicochemical properties of the soils for each season of the year and this generate a variable environment, which affect the electrochemical responses on steel–soil interface.

The corrosion evaluation was carried out simulating the conditions of deteriorated coating (bare steel); this includes steel surface exposed to clay soil affected by seasonal fluctuations in a tropical zone. These soils were characterized, without any further treatment as were found in the field (dry season). Moreover, some samples were taken and prepared to analyze in laboratory. For each soil sample, 60 mL of deionized water was added to simulate the rainy season (saturated soils). Electrochemical evaluations were carried out after 3 h of exposure time at room temperature. Because soil is a system with high resistivity and impedance, it is necessary to carry out IR-drop compensation using two platinum rods that were used as an auxiliary electrode. In addition, the IR-drop correction obtained from the experimental potentiodynamic curves was investigated.

In clay from Campeche (Clay-C), the more susceptible steel to corrosion was X65, whereas in clay from Tabasco (Clay-T), the more susceptible steel to corrosion was X80 steel. Electrochemical results show that despite higher-degree steels providing higher strength and hardness, the order of corrosion susceptibility is random, which can be attributed to different microstructures in the steels. The complexity of the corrosion process on five steels was evident when steel samples were exposed to different soils. The higher corrosion rate was obtained in X65 steel (0.5 mm/year).

The paper clearly identifies any implication for the research.

The electrochemical responses of different steels exposed in two types of clay soil explained the corrosion complexity that can be attributed to changes in physicochemical properties of the soils, which are because of changes in seasons (dry and rainy) and the microstructure of each steel related to the process of fabrication. Suggesting that the increase in mechanical properties such as hardness and resistance of the pipeline steels could not be associated with its corrosion resistance, the corrosion susceptibility is more dependent on the microstructure of the steels.

To demonstrate that Bateson's path‐breaking life and breakthrough thinking have directly (and indirectly) inspired a profound shift which has specific and practical effects in the physical world – as well as in the world of ideas.

The paper describes an outstanding initiative inspired by Bateson's ideas and work.

Colombia's Gaviotas, situated far from the traditional centers of power and prestige, is the scene of an extraordinary whole system's experiment which is successfully applying Batesonian ideas in a harsh and troubled setting. Colombia is a country where environmental degradation, violence and instability are rampant. The paper examines some of the successes already achieved in Gaviotas, the path that lies ahead and the new opportunities being pursued by the Gaviotas project's developers. The paper attempts to understand how scientists are actively using Bateson's epistemology in their work.

This paper aims to enrich the Bateson memorial by demonstrating that cutting‐edge ecological thinking, as pioneered by Bateson, is being applied around the globe in ways both surprising and profound.

This paper identifies a unique attempt to manifest, in the most difficult circumstances, that Bateson's ecological concepts and values are not abstraction s and that change is a process which can occur in the most unlikely places.