Production Zones Research Articles

Diet During the Late Initial Period (1100–800 BC) in the Chavín Heartland: New Data from Canchas Uckro (North-Central Peru)

During the late Initial Period (c. 1100-800 BC), the Conchucos region of highland Peru witnessed the formation of the ceremonial and “proto-urban” center of Chavín de Huántar (c. 1000-500/400 BC). An important question regarding Chavín de Huántar centers on the nature of its subsistence economy during the time when it was first founded. In this paper, we present new results from zooarchaeological, starch granule, and stable isotope (δ13C and δ15N) analyses to reconstruct diet from Canchas Uckro, a settlement located in Chavín de Huántar's heartland region. Founded c. 1100 BC and abandoned just after 800 BC, Canchas Uckro provides insight into socioeconomic processes during the early phases of Chavín de Huántar. Extant faunal remains suggest deer comprised an important component of the diet, while camelids constitute a minor proportion of the assemblage. Starch granules recovered from the pottery indicate that domesticated cultigens (maize, potato, and manioc) were obtained from different highland production zones. δ13C and δ15N analysis of a sample of human skeletal remains, coupled with Stable Isotope Analysis in R (SIAR) mixing models, demonstrate that C3plants constitute most of the diet, while maize was not intensively consumed. δ13C and δ15N further indicate that deer made up 25-50% of the diet. The results of this study add to a gro wing corpus of data on subsistence practices in the north-central and northern highlands of Peru prior to the widespread adoption of domesticated camelids.

Substantiation of Drilling Parameters for Undermined Drainage Boreholes for Increasing Methane Production from Unconventional Coal-Gas Collectors

Decarbonization of the mining industry on the basis of closing the energy generation, on the basis of cogeneration of coal mine methane, and on the internal consumption of the mine is a promising direction in ensuring sustainable development. Known problems of deep underground mining do not allow for realizing the potential of man-made gas reservoirs due to the deterioration of the conditions of development of reserves of georesources. The aim of the work was to improve recommendations for the substantiation of drilling parameters for undermined drainage boreholes for increasing methane production from unconventional coal-gas collectors. The authors’ approach innovation lies in the possibility of using the established patterns of better natural stability of undermined boreholes to optimize them as spatial orientation parameters in an existing drilling passport for the improvement of methane extraction productivity. For this purpose, smoothing (LOESS) of the experimental data of two similar types of wells was used; then deterministic interpolation methods in combination with a three-dimensional representation of the response function in “gnuplot” were used. As a result, it was found that the increase in the inclination angle from 40° to 60° leads to a significant transformation of the model of the studied process, accompanied by a decline in the dynamics of methane emission and a decrease in the distance of the productive work zone of this type of well from 13 to 5 m before the roof landing, which then is replaced by a sharp increase in the productive work zone up to 35 m ahead of the longwall face. This allows under specific conditions for recommending increasing the productivity of methane capex from technogenic disturbed coal-gas reservoir replacement of wells with a smaller angle of rise to the transition to a more frequent grid of clusters from wells #4.

ASSESSMENT OF SOIL POLLUTION IN KHABAROVSK BENZ(A)PYRENE

Introduction. In cities with developed industry and infrastructure, the problem of pollution with supertoxicants, including benz(a)pyrene (BP), is relevant. In most of the analyzed works, there is an excess of regulatory requirements for the content of BP in the soils of urban areas. There is no information in the literature about BP contamination of soils in the cities of the Khabarovsk Territory.
 Background. Assessment of the level of contamination of benz(a)pyrene functional zones of Khabarovsk.
 Objects and methods. The content of benz(a)pyrene in the surface layer of the soil of industrial, agricultural and residential zones of Khabarovsk was studied using a liquid chromatograph "Waters HPLC 2475". 78 samples were examined, a significant part of which was taken in residential (38 samples) and industrial (34 samples) zones. Assessment of compliance with permissible standards and determination of the degree of contamination of the studied soils were carried out in accordance with SanPiN 2.1.3684-21 and SanPiN 1.2.3685-21.
 Results. It was found that 62.8% of all the samples studied have the category "clean", while 35.9% of the samples were not contaminated. The share of samples with the category: acceptable was 12.8%, dangerous - 11.5%, extremely dangerous - 9%. The most polluted functional zone is residential buildings, since it is located along the perimeter of production zones and, directly, the largest stationary sources of emissions falling into their dispersion zones. Almost all soil sampling points in which the content of benz(a)pyrene exceeds 5 MPC (maximum permissible concentrations) are located in the zones of influence of Khabarovsk CHP No. 2 and Khabarovsk Oil Refinery.
 Conclusions. The current situation is due to the imperfection of urban planning solutions that do not take into account the aerogenic introduction of pollutants and their accumulation in the soils of the residential area.

Impact of Major Function-Oriented Zone Planning on Spatial and Temporal Evolution of “Three Zone Space” in China

Major function-oriented zone (MFOZ) planning is an important blueprint for the spatial development and protection of the Chinese national territory. The “Three Zone Space” (TZS) perspective, including agricultural space, ecological space, and urban space, is an important principle and method for the transformation and diffusion of MFOZ planning to implement territory planning from the central government to local branches. More than ten years have passed since the release of the MFOZ plan in 2010 in China, but there is still a lack of comprehensive and systematic analysis of the dynamic characteristics of the TZS under the impact of MFOZ planning. Therefore, based on high-resolution remote sensing land use data from 2010 to 2020, this paper systematically analyzes the changing characteristics of the TZS on the national scale by reasonably determining TZS areas in China. The main results are as follows: in 2020, the proportions of ecological space, agricultural space, and urban space in China were 78.635%, 20.083%, and 1.282%, respectively. The TZS areas reflected the spatial pattern of MFOZs in China. From 2010 to 2020, the spatial heterogeneity of the TZS changes was significant. In China, agricultural space and ecological space as a whole showed a decreasing trend, with dynamic degrees of −0.05% and −0.04%, respectively, while urban space showed a significant expansion trend, with a dynamic degree of 4.69%. The temporal change processes of the TZS in the periods of 2010–2015 and 2015–2020 were noticeably different. The agricultural space first showed an increasing trend and then a decreasing trend. The ecological space showed a decreasing trend in the two periods, while the urban space showed a significant expansion trend in the two periods. From 2010 to 2020, the urban spatial structure of the optimized development zones tended to be stable, and the ecological space reduction in the key ecological function zones has gradually been curbed, but the agricultural space in the main agricultural production zones has shown a slight decline. On the whole, the dynamic changes in the TZS from 2010 to 2020 in China are basically in line with the governance objectives of territorial space. The reasonable allocation and development of the “three zone space” is of great significance for protecting the natural and ecological environment.

Achieving sustainable development through economic growth, energy consumption, and agricultural productivity in China

AbstractLarge amount of carbon emission is the main hazard to environment and human health. The aim of this research is to investigate the impact of economic growth, forest zone, agricultural productivity, and energy consumption on environmental pollution in China using time series data from 1980 to 2020. The underline research utilized dynamic ordinary least‐squares (DOLS) method, Johansen and Engle–Granger cointegration tests, and the autoregressive‐distributed lag (ARDL) technique to analyze the varying data set. To compare findings, fully modified ordinary least squares (FMOLS) and canonical cointegrating regression (CCR) estimators are estimated. Energy use and population raise CO2 emissions with 1% economic development. Long‐term CO2 emissions may be reduced by 1% agriculture production and forestry zone growth. The Granger causality test showed causation between all variables. Results reveal that China might achieve sustainable development goals by cutting down CO2 emissions and mitigate global climate change. The underline research presents policy recommendations for attaining environmental sustainability in China through green investment by reducing carbon emissions. These policies highlight promoting use of renewable energy, financing green technological progression in agricultural productivity, and the ecological feasibility of China's forests.

OPTIMIZATION OF CONCENTRATIONS OF DRILLING REAGENTS BASED ON GUMS USING MATHEMATICAL MODELING METHODS

The article is devoted to the use of regression analysis to analyze the use of biopolymer reagents based on gums of various manufacturers — domestic reagent brand KK (Russia), foreign Kem-X (USA) and Rodopol-23R (France).The use of these reagents in the composition of drilling fluids (BR) leads to the fact that BRs exhibit pseudoplasticity properties that are necessary for accident-free passage of multi-meter horizontal intervals and qualitative penetration of productive zones at various fields in Russia, including those in the Volga-Ural region. Equations of dynamic shear stress (DPS) and effective viscosity (EV) were obtained depending on the concentration of the examined gum (biopolymer reagent) and shear rate. The effectiveness of various gums (biopolymer reagents) and comparative analysis of the regression equations of the main parameters of drilling fluids using these reagents were evaluated.

Geophysical Modeling and Its Contribution on the Reservoir Characterization of Al Baraka in El Gallaba Plain, South Egypt

Summary The early Cretaceous formations in recent years are considered significant potential hydrocarbon-bearing rocks in many rift basins such as Komombo, south Egypt. Therefore, this study is focused on the critical analysis and interpretation of well logging together with seismic reflection data on the Al Baraka petroliferous reservoir in the Komombo subbasin. The interpretation of these data was used to construct the first 3D geophysical models in this area which were subsequently interpreted in terms of their potential to be hydrocarbon-bearing or not. The 3D petrophysical models were deduced to illustrate the spatial distribution and propagation of the petrophysical properties (laterally and vertically) within the reservoir. Additionally, 3D seismic models were prepared to get a comprehensive, in-depth picture of how the productive hydrocarbon reservoir zones are structurally controlled in different depths. So, these models are crucial for explaining reservoir characteristics and providing supported geological reservoir models for precise reservoir performance prediction. This study aims to differentiate and determine hydrocarbon potential zones in terms of the petroleum system. The results of these progressive analyses showed that only two zones (C and D) in the Six Hills Formation are considered the most productive zones because they have a large thickness of sand bodies, low-water saturation values, high porosity, and high permeability. These zones are located in the northeastern and central parts of the studied area, which represent the depocenter of the subbasin. This evidence supported and confirmed the presence of petroleum accumulations in certain zones within the Six Hills Formation. Therefore, this work can give and encourage experts with adequate knowledge to understand the development of the rift basins in Komombo and other basins in middle and south Egypt.

Particle-in-cell modeling of electron beam generated plasma

Plasmas generated using energetic electron beams are well known for their low electron temperature (T e) and plasma potential, which makes them attractive for atomic-precision plasma processing applications such as atomic layer etch and deposition. A 2-dimensional particle-in-cell model for an electron beam-generated plasma in argon confined by a constant applied magnetic field is described in this article. Plasma production primarily occurs in the path of the beam electrons in the center of the chamber. The resulting plasma spreads out in the chamber through non-ambipolar diffusion with a short-circuiting effect allowing unequal electron and ion fluxes to different regions of the bounding conductive chamber walls. The cross-field transport of the electrons (and thus the steady-state characteristics of the plasma) are strongly impacted by the magnetic field. T e is anisotropic in the electron beam region, but low and isotropic away from the plasma production zone. The plasma density increases and the plasma becomes more confined near the region of production when the magnetic field strengthens. The magnetic field reduces both electron physical and energy transport perpendicular to the magnetic field. T e is uniform along the magnetic field lines and slowly decreases perpendicular to it. Electrons are less energetic in the sheath regions where the sheath electric field repels and confines the low-energy electrons from the bulk plasma. Even though electron and ion densities are similar in the bulk plasma due to quasi-neutrality, electron and ion fluxes on the grounded chamber walls are unequal at most locations. Electron confinement by the magnetic field weakens with increasing pressure, and the plasma spread out farther from the electron beam region.

Development of a mathematical model for a compound technological complex of vanyukov melting in order to control the material and thermal regime

This article presents a mathematical model in the form of static equations of dependencies of input and output flows based on the equations of material and heat balance for the purposes of operational planning and control of the complex technological complex of Vanyukov melting (PV). Dynamic characteristics are presented for the purpose of controlling the thermal regime based on the technology of the developed melting process with blowing from below. As a result of the study, the developed mathematical model for controlling the smelting process when calculating the material flows of the charge will allow tracking changes in the thermal state of the smelting (by the copper content in the matte). This model can quite well describe the dynamics of the state of the process, both when establishing the impacts aimed at increasing the heating of the furnace, and at reducing its heating. Based on the equations, a computer model based on the dynamic programming method in the MATLAB software package has been developed. The scientific novelty lies in the fact that for the first time, the structure of a mathematical model has been developed that describes the processes occurring in the over-tuyere zone and the sludge zone of the smelting products.

Integrating Petrophysical Analysis and Seismic Interpretation for Oil and Gas Reserves Estimation in “TAU” Field, Jatibarang Sub–Basin, North West Java Basin

The focus of the study is the North West Java Basin, specifically the Jatibarang Sub Basin within it. The research aims to identify new potential areas for hydrocarbon reserves using seismic interpretation, and tetrophysical analysis, also calculate the volume of reserves in those areas. According to the study, 2 potential areas for hydrocarbon reserves were identified in the Parigi Formation, 2 were identified in the Baturaja Formation, 3 were identified in the Talang Akar Formation, and 1 was identified in the Jatibarang Formation. No new potential areas were discovered in the Cibulakan Formation. The study used petrophysical interpretation of six wells to determine the average values of shale volume (9.57% to 29.87%), effective porosity (19.45% to 21.67%), and water saturation (69.73% to 93.50%) for each potential zone. The TAU-5 well in the Baturaja Formation (Zone 1, Zone 2, Zone 3, and Zone 4) was determined to be the most economically viable zone for production based on the values of shale volume, porosity, and water saturation. The volume of hydrocarbon reserves in the BR-1 potential zone was calculated to be 182.741281 MBO in OOIP and 177.85122 BCF in OGIP. The BR-2 potential zone had an OOIP value of 1,197.534148 MBO and an OGIP of 1165.488764 BCF.

Spatial and Temporal Rainfall Analysis of the Bidi Tobacco Growing Areas of India.

The monsoon extremities, such as heavy rainfall, drought, and cyclones are becoming frequent across India and causing substantial damage to commercial crops. To predict/identify the trend in rainfall of Bidi tobacco growing areas were studied for variability, trend, and detection of any change in monthly rainfall over the years (1990-2020) using Mann-Kendall trend analysis and Sen’s slope tests. Monthly rainfall in three unique Bidi production zones has shown distinct trends. A positive trend was observed in March, April, August, September, November, and December while negative trends were in June and July months in Gujarat. During the crop growth period, the trend is positive except in October, the magnitude of change was negligible. However, supplemental irrigation is to be planned during water deficit periods of the nursery (June and July) and critical crop growth periods. In Karnataka, a positive trend from February to October was observed while a negative trend during November, December, and January. The magnitude was high in January (+) and September (-) and significant. The period of negative trend has coincided with the harvesting hence, the crop may not get affected. However, high rainfall during the crop growth period causes a detrimental effect. To mitigate the inundation proper drainage facility should be created through field channels to flush out excess water to avoid saturation at the root zone as this crop is especially extremely sensitive to poor aeration and anaerobic conditions. A positive trend was observed in January, February, March, June, August, and September months in Andhra Pradesh, whereas a negative trend was high in October & November which coincided with crop growth and might significantly affect Bidi tobacco. The positive trend in rainfall during June is high and the same can be utilized for nursery during July-August through proper moisture conservation measures.

Advancing Adaptive Leadership Through Adaption‐Innovation Theory: Enhancements to The Holding Environment

While adaptive leadership is a useful framework for leadership practitioners, there is limited empirical research supporting its conceptual tools and tactics. Kirton's adaption‐innovation (A‐I) theory contends individuals have innate problem‐solving style preferences for more or less structure. In the current conceptual paper, we examine the theoretical underpinnings of adaptive leadership and A‐I theory within the context of complex problem‐solving. We connect A‐I theory to concepts from adaptive leadership to link a more rigorous and empirically supported theory to a popular practice. We go further to explore how a leader's A‐I style informs the maintenance of an adaptive leadership holding environment (HE), particularly with regard to facilitating a productive zone of disequilibrium (PZD).

Assessment and Identification of water potential area for fodder production through irrigation techniques in Borana and Guji Zones, Oromia, Southern Ethiopia

The project entitled, “Assessment and identification of water potential areas in Borana and Guji zone” to assess and identify the water potential with enough catchment and suitable command area that can improve the sustainable fodder production of the land and livestock supporting the Borana and Guji Pastoral and agro pastoral System. The Borana and Guji rangelands were well-known for fodder production potential, However, this production is declined from year to year due to different factors such as; Physical factors namely; grazing pressure, human activity, bush encroachment and climate variability as well as Policy attention and good government are the others most important factors. The land use change and climate variability are the key factor for affecting pastoralists’ and agro pastoralists’ livelihoods that cause food and feed insecurity both Borana and Guji zone. Therefore, the main objectives of assessment confidential into three classes, firstly, to assess the water potential areas of Borana and Guji rangelands, secondly, to identify and classify water potential sources and their limitations both zones that thematic areas of mercy corps, Thirdly, to improve communities’ livelihoods and increasing adaptive capacity of societies to climate variability and environmental and others social negative events in study areas. The assessment was conducted two zones of Borana and Guji Zones. During the assessment four main offices were selected for interview at zonal, woreda and PA level, those offices were Irrigation office, Land use office, Pastoral Development office and Water office, these cascaded to woredas accordingly. After selected and discussed with those main offices, we had been observed two main important offices that could play a crucial role of arranging and facilitation for the assessments. We assessed twelve woredas and identified thirty nine water potential sites from Borana zone while four woredas of Guji zone were assessed and eleven sites were identified as irrigation potential. The result indicated 50 sites were identified as water potential in Both Borana and Guji Zones for fodder production through irrigation techniques. Our result showed that 78% of water potential sites were found in Borana zone, while 22% of irrigation potential sites were found in Guji zone. We identified four water potential or sources through different reservoir construction techniques such as micro earthen dams 22 sites, rivers 8 sites, ponds 15 sites and depth wells 5 sites. Our Result showed that 44% of water potential sources were MEDs, 16% were river streams, while 30% shows pond and 10 % shows depth well respectively. The total of 13272 household head can serviced from more than 6636 hectares, while 18280 household heads can be benefited from 9140 hectares from studied sites’ in Guji zone. Totally, about 31552 household head could be diversify and improve their livelihood through irrigation from 15776 hectares of land. We identified 50 sites, from the selected site 78% found in Borana zone, while 22% found in Guji zone. In Borana Zone, the micro earthen dam is the major source of water, than pond water and river water sources respectively. Finally, depth well is ranked fourth. We concluded that there are water potential sources for irrigation for forage /fodder and others purpose production in Borana and Guji Zone in studied areas. Therefore, we recommended that the different development agencies, NGOs, Government and private should involve in fodders and others production purpose through irrigation support to improve pastoralists’ and agro pastoralists’ livelihoods in Borana and Guji zone. Due to time limitation and security issues, assessment was not cover each of potential sites of Borana and Guji Zones. Further study will be recommended to cover each potential site of Borana and Guji zones.

Chloride penetration and binding behavior in unsaturated alkali-activated slag mortars

A comprehensive study from detailed microstructure analyses to mass transport investigations was implemented to explore chloride penetration of unsaturated alkali-activated slag (AAS) mortars accounting for chloride binding behaviors. Unsaturated chloride penetrations reflected from diffusion cases of instantaneous plane source and sorption cases of wetting-drying exposure were elaborated in relation to solid hydrates and pore structure features. It is found that the specimen with lower saturation has a slower chloride diffusion but a larger chloride penetration under wetting-drying cycles. Slag mortars with sodium hydroxide activation exhibit higher chloride binding capacity owing to more hydrotalcite-like phases and higher Ca/Si ratio of C-(N-)A-S-H gels in the outer product zones as compared to sodium silicate activated slag mortars, regardless of the saturation. Accelerations of the chloride penetration under the wetting-drying exposure are limited in saturated AAS specimens while for unsaturated AAS specimens more wetting-drying cycles result in the inner layers to be gradually diffusion-controlled. The chloride binding capacity of AAS specimens follows Langmuir's isotherm and clearly decreases with a lower saturation. It is advised to consider the electrical double layer effect within narrow pores when applying rapid chloride migration tests for AAS systems.

Achieving high yield and nitrogen agronomic efficiency by coupling wheat varieties with soil fertility

Wheat breeding has progressively increased yield potential through decades of selection, markedly increased the capacity for food production. Nitrogen (N) fertilizer is essential for wheat production and N agronomic efficiency (NAE) is commonly index used for evaluate the effects of N fertilizer on crop yield, calculated as the difference of wheat yield between N fertilizer treatment and non-N fertilizer treatment divided by the total N application rate. However, the impact of variety on NAE and its interaction with soil fertility remain unknown. Here, to clarify whether and how wheat variety contributes to NAE, and to determine if soil conditions should be considered in variety selection, we conduct a large-scale analysis of data from 12,925 field trials spanning ten years and including 229 wheat varieties, 5 N fertilizer treatments, and a range of soil fertility across China's major wheat production zones. The national average NAE was 9.57 kg kg−1, but significantly differed across regions. At both the national and regional scales, variety significantly affected NAE, and different varieties showed high variability in their performance among low, moderate, and high fertility soils. Here, superior varieties with both high yield and high NAE were identified at each soil fertility fields. The comprehensive effect of selecting regionally superior varieties, optimizing N management, and improving soil fertility could potentially decrease the yield gap by 67 %. Therefore, variety selection based on soil conditions could facilitate improved food security while reducing fertilizer inputs to alleviate environmental impacts.

Enhanced history matching process by incorporation of saturation logs as model selection criteria

This paper proposes a methodology for an alternative history matching process enhanced by the incorporation of a simplified binary interpretation of reservoir saturation logs (RST) as objective function. Incorporating fluids saturation logs during the history matching phase unlocks the possibility to adjust or select models that better represent the near wellbore waterfront movement, which is particularly important for uncertainty mitigation during future well interference assessments in water driven reservoirs. For the purposes of this study, a semi-synthetic open-source reservoir model was used as base case to evaluate the proposed methodology. The reservoir model represents a water driven, highly heterogenous sandstone reservoir from Namorado field in Brazil. To effectively compare the proposed methodology against the conventional methods, a commercial reservoir simulator was used in combination with a state-of-the-art benchmarking workflow based on the Big Loop™ approach. A well-known group of binary metrics were evaluated to be used as the objective function, and the Matthew correlation coefficient (MCC) has been proved to offer the best results when using binary data from water saturation logs. History matching results obtained with the proposed methodology allowed the selection of a more reliable group of reservoir models, especially for cases with high heterogeneity. The methodology also offers additional information and understanding of sweep behaviour behind the well casing at specific production zones, thus revealing full model potential to define new wells and reservoir development opportunities.

PREREQUISITES FOR THE DEVELOPMENT OF INDUSTRIAL LANDS OF TERRITORIAL COMMUNITIES

Within the framework of the article, the main direction of research is aimed at increasing the efficiency of land use. Based on the analysis of the ratio of functional and target purpose, it can be concluded that increasing the efficiency of the use of industrial lands, first of all, depends on the solution of the following issues:
 - target designation of land parcels occupied by industrial facilities; - actual use of land parcels for the specified purpose;- legal status of objects located on industrial lands.
 Based on the above-mentioned components of effective use of territories, were systematized three most common cases. The first case is the best from the point of view of the further use of the land of the territorial community, because for the existing land parcel the category of industrial land, the type of functional purpose corresponds to the production zone. Such a case is ideal, it rarely occurs in practice, but it contains a few positive aspects in terms of ensuring the capabilities of territorial communities. Along with the land issue, the issue of filling the budget of the territorial community through land tax and personal income tax could be resolved, and the employment situation of residents could be improved.
 The second case is the most common in practice. Several different options are possible: the actual use does not correspond to the functional and/or intended purpose and/or is not used at all, but the land parcel, real estate and land use subject have all legal identifiers. Territorial communities may not receive income due to incorrect calculation of payment amounts for land. Incorrect consideration and use of the zones of restrictions around regime-forming objects can negatively affect the owners and users of adjacent land parcels, or unreasonably limit the possible types of effective use of territories. If the land parcel and the object of immovable property are generally not in economic circulation, then in this case there are also certain risks for the community, similar to those mentioned above: lack of income, lack of opportunities for effective disposal of land, and inconsistency of the areas of effect of restrictions around regime-forming objects the actual situation.
 The third case is not so common in practice, but it also occurs. The situation looks like this: the industrial object is used within the category, the intended purpose, considering the functional purpose of the corresponding territory, but due to various reasons, which may be of a historical nature, there are no legal documents for the land parcel and/or real estate and /or title-establishing documents of a legal entity. All this leads to inefficient use of land and lack of revenue to the budgets of territorial communities.

Role of formation and decay of seston organic matter in the fate of methylmercury within the water column of a eutrophic lake

Abstract. Anoxic microniches in sinking particles in lakes have been identified as important water phase production zones of monomethylmercury (MeHg). However, the production and decay of MeHg during organic matter (OM) decomposition in the water column and its relation to the total Hg concentration in seston are poorly understood. We investigated total Hg and MeHg in relation to chemical changes in sinking seston and hydrochemical settings in a small and shallow (12 m deep) eutrophic lake during phytoplankton blooms from April to November 2019. The results show that MeHg proportions reach up to 22 % in seston in oxygen super saturation at the water surface and highest values (up to 26 %) at the oxic–suboxic redox boundary. MeHg concentrations were highest in May and November when algal biomass production was low and seston were dominated by zooplankton. Biodilution of MeHg concentrations could not be observed in the months of the highest algal biomass production; instead, MeHg and THg concentrations in seston were comparatively high. During suboxic OM decomposition and with decreasing redox potential (Mn and nitrate reduction), the concentration and proportion of MeHg in seston strongly decreased (<0.5 %), whereas total Hg concentrations show a 3.8- to 26-fold increase with water depth. Here, it remains unclear to which extent biodilution on the one hand and OM decomposition on the other alter the MeHg and THg concentration in seston. Changes in OM quality were most intense within or slightly below the redox transition zone (RTZ). The concentrations of MeHg and THg in seston from the RTZ were comparable to those found in the sediment trap material which integrated the changes in seston composition during the entire sampling period, suggesting that changes in the MeHg and THg content in the hypolimnion below the RTZ are comparatively small. Our study suggests that, in shallow eutrophic lakes, the water phase formation and decomposition of MeHg is intense and controlled by the decomposition of algal biomass and is, assumedly, largely disconnected from Hg methylation in sediments, similar to what has been observed in deep oligotrophic lakes.

Influence of Anodization Process on Improvement of Corrosion Resistance of Tubing from Aluminium Alloys

Full functioning of wells in oil and gas fields is impossible without the use of tubing. Main function of tubing is transportation of gases and liquids produced in productive zone to well surface. In addition, tubing acts as a kind of insulator that protects the gas and liquid transported through them from the walls of the well, and also prevents the occurrence and development of corrosion, deposits of paraffin and asphaltene on casing pipes. The tubing pipe placed in the well is also necessary in order to ensure the carrying out of downhill and repair work, which is regularly necessary. Standard tubin g (tubing) as a result of technological difficulties does not undergo a strengthening operation. When manufacturing tubing and locks to them from alloyed steels, the main attention is paid to improving mechanical properties, which is achieved by thermal and chemical-thermal treatment. However, the practice of operating tubing shows that the introduction of these measures does not solve the issue of reliability, since threaded connections for the coupling and nipple remain vulnerable sections of tubing. Tubing (tubing) during its operation experiences significant loads and is in constant contact with aggressive media, which leads to serious requirements for their quality. The possibility of replacing its production from alloyed steels with aluminum alloys, for example, AlCuMg2 will facilitate the design by 2.5 times, prevent the tendency to stress corrosion cracking (SCC) in a hydrogen sulfide-containing medium and eliminate inhibitory protection. The main disadvantage of aluminum alloys is the tendency to pitting corrosion. It is possible to improve the protective properties of the passive film on aluminum alloys by anodizing.

Petrophysical Calculation Analysis and Determination of Cut-Off in Betung Field, Jambi-Sub-Basin, South-Sumatera-Basin

Petrophysical properties provide a comprehensive approach to reservoir characterization, in which reservoir quality is of paramount importance. The main controllers for reservoir quality are porosity, permeability and clay content. Petrophysical models are used by utilizing the correlation between tool response (logging) and rock and fluid properties. These petrophysical results will be cut-off to distinguish productive and unproductive parts of a reservoir. Petrophysical and cut-off calculations in the Betung Field are applied to determine the quality and productive zone of the Air Benakat Formation reservoir. The direction of field development (infill wells) is based on the quality of the reservoir and productive zone obtained based on the results of petrophysical and cut-off calculations. This research was conducted in Layer 5 (L-5) of the Betung Field using the main data, namely well logs (Gamma ray, density, neutron, resistivity). Well logs were processed to obtain petrophysical values using Interactive Petrophysic and Microsoft Excel software. Petrophysical results were then cut-off on clay content, porosity and water saturation, so that a productive zone was obtained from the Betung L-5 field. Petrophysical and cut-off results show L-5 is a Hydrocarbon prospect zone with an average petrophysic value for well 210 (Vclay: 32%, porosity: 25% and water saturation: 65%); well 220 (Vclay: 35%, porosity: 30% and water saturation: 38%); well 222 (Vclay: 8.2%, porosity: 31% and water saturation: 28%). The resulting cut-off values for well 210 (Vclay: 42.6%, porosity: 17% and water saturation: 98%); well 220 (Vclay: 26.6%, porosity: 22.4% and water saturation: 50.3%); well 222 (Vclay: 18%, porosity: 17% and water saturation: 70.4%).