Stability Of Grains Research Articles

STUDY OF THE SAFETY OF GRAIN POST-ALCOHOLIC GRAIN

Introduction. When producing alcohol, only the starch is extracted from the grain; the remainder of the grain containing various biologically active substances (BAS): proteins and amino acids, reducing substances, uronides, flavonoids, lipids, vitamins and provitamins, with added enzymes is called post-alcohol grain grains, its volume is 12-13 times greater than the volume of alcohol and practically not used. To substantiate the prospects for the pharmaceutical use of grains, two areas of processing have been proposed: to obtain total biologically active substances (“Biobardins”) and in-dividual betaine hydrochlorides with different pharmacological properties. The assumption that the cause of grains spoilage is labile biologically active substances, the isolation of which will determine the stability of grains, requires experimental confirmation. The purpose of the work is to study the chemical and microbiological safety of grains (wheat, corn, barley, millet) before and after its processing (after obtaining Biobardins and betaines). Material and methods. The object of the study is various types of grain grounds (wheat, corn, barley, millet) produced in 2021–2022 by distilleries in the Stavropol Territory. We studied the chemical safety of industrial waste according to the integral and most informative indicator of anthropogenic environmental pollution - the indicator “chemical oxygen consumption” (COC), determined by dichromatometry. Microbiological quality control of grain grounds was carried out in accordance with the requirements of general pharmacopoeial monograph GPM.1.2.4.0002.18 “Microbiological purity” of the State Pharmacopoeia of the Russian Federation XIV. Results. The indicator of “chemical oxygen consumption” (COC), which characterizes the chemical safety of waste and determined by dichromatome-try, decreased by 4.1 times (by 75.6%) when obtaining Biobardinov from stillage (from 54503 to 13205 mg O/l), and when obtaining betaines - 3.5 times (by 71.4%) (from 54503 to 15490 mg O/l). In both options, the recycled grains corresponds to non-hazardous industrial waste. According to the results of specific qualitative reactions, the processed grains contains no biologically active substances characteristic of the original grains: proteins and amino acids, reducing sugars, uronides. Microbiological control of the processed grains also confirmed its microbiological safety in terms of the content of aerobic bacteria, enterobacteria, fungi and the absence of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella. Conclusion. Thus, the use of various types of post-alcohol grain grains as pharmaceutical raw materials for the production of total and individual medicines made it possible to solve 2 problems: to use grains as a medicinal raw material and to reduce the technogenic impact of grains on the en-vironment.

Multiscale characterisation study on the effect of heat treatment on the microstructure of additively manufactured 316L stainless steel

Additively manufactured 316L components are known to exhibit complex three-dimensional microstructures on multiple length-scales. The effect of heat treatment on the stability of grains and dislocation cell structures within the microstructure has previously been investigated but there are appreciable disagreements surrounding the nature of the texture that is present in the specimens, and there is also limited published work on the compositional homogeneity of specimens, particularly on the atomic scale, after heat treatments. In this study, we investigate the effect of applying two different heat treatments to 316L components produced by laser powder bed fusion before characterising them using a combination of electron microscopy and atom probe tomography. The importance of using multiple characterisation techniques, which span from the nanometre to micrometre scale, in addition to carefully and accurately describing analysis methods when investigating the evolution of the microstructure of additively manufactured 316L steels is demonstrated. Our EBSD (Electron Back Scatter Diffraction) results show the presence of a strong texture in the build direction of the samples, and a reduction in morphological texture as a result of heat treatment. TEM (Transmission Electron Microscopy) results indicate a dissolution of the dislocation cell structure that forms during solidification. Atom probe tomography was used to investigate compositional homogeneity in the samples and indicated that there are regions enriched in Cr, Mn, Mo, and Ni in the As-Printed samples that are likely associated with the dislocation cell walls. The atom probe results also reveal the presence of impurities, such as Co, which were not detected in the feedstock powder.

The Impact of Extreme Temperatures on Grain Production in the Huaihe River Basin

The Huaihe River Basin is an important major grain producing area in China, maintaining the stability of grain output is of great significance to food security. However, with global warming, the frequency of extreme temperature events has increased, and the frequent meteorological disasters have brought great challenges to the stable supply of food production. In this paper, the impact of extreme temperature on grain production in the Huaihe River Basin was analyzed by using the daily temperature and agricultural production related data of 28 prefecture-level cities in the Huaihe River Ecological Economic Belt from 2001 to 2020. The following conclusions are drawn: 1) The influence coefficient of extreme high temperature on grain production in the Huaihe River Basin is -0.021, extreme low temperature has no significant impact on food production. 2) The effects of extreme temperature on food production in different regions in the river basin were heterogeneous, but the overall impact was negative. The influence coefficients of extremely high temperature days on the eastern region and Midwest region were -0.035 and -0.052, respectively, while the influence coefficients of extremely low temperature days on the eastern region were -0.413. The results showed that the increase in the number of extremely high temperature days would reduce production in the eastern region andMidwest region of the basin, while the northern region was not significantly affected by extreme heat. The increase in the number of extremely low temperature days will reduce grain production in the eastern region, and the impact on the Midwest region and the northern region will not be significant. Based on the above conclusions, three suggestions are put forward to maintain the safety of food production in the Huaihe River Basin: 1) enhance the ability to detect climate change in the basin; 2) Protect the stability of grain cultivated land in the river basin; 3) Innovative breeding of climate-resilient food crop seeds.

Analysis of Fatty Acid Composition in Sprouted Grains.

A whole-grain diet is associated with the prevention of metabolic syndromes, including obesity, diabetes, and cardiovascular diseases. Sprouting improves the nutritional profile and bioactive properties of grains, which are important for use as raw ingredients in the food industry. The aim of this review was to examine the lipid and fatty acid composition of germinated grains. The methods discussed include germination and analytical procedures for determining fat and fatty acid contents of grains. The effects of sprouting on the fat content and storage stability of grains were also assessed. Lipid levels ranged from 1.43% to 6.66% in the sprouted grains. The individual fatty acid content of grains changed depending on the germination conditions (17-37 °C, 1-9 days). Limited findings showed that sprouting grains at higher temperatures (20-25 °C) and longer times generated a healthy balance of omega-6 and omega-3 fatty acids, which is beneficial to humans. Future studies are needed to determine the optimum incubation and germination periods specific to each grain to improve the omega-6/omega-3 ratio. Free fatty acids were produced more slowly and levels of oxidation products were lower in sprouted grains than in the raw ingredients when stored for a year. Additional studies are required to investigate the oxidative stability and shelf life of sprouted grains.

State and development of grain storage engineering and technologies in Ukraine

Topicality. These researches are due to the grain storage problem, the features of maize grain storage in metal silos under the various environmental factors, as well as more efficient using the material and technical facilities, including the grain storages of new generation. Purpose. To establish the types of grain storage facilities that are most appropriate for storing the yield of different crops, to improve metal silos and maize grain storage technologies. Materials and Methods. During experiments on maize grain storage, we used the metal silo equipped with a system of sensors to measure the temperature in different places of grain heap. We studied two models of grain storages, such as a standard construction (control) and an experimental one thermal isolated with a polyurethane layer. During the storage experiment, grain quality was monitored on grain moisture content, dockage, damage and germination. Results. Different types of grain storage facilities storing main volume of grain harvest were characterized; the technical, economic and technological advantages and disadvantages of grain storage were highlighted; directions for further development are outlined. The features of maize grain storage in the metal silos under influence of external meteorological conditions for 60 day were established. Temperature fluctuations were 7.1–13 °С in grain storage with thermal insulation, 4.5–25.9 °С – without insulation. As a result of significant temperature fluctuations, the grain was moistened by 2.2 %, its acidity increased by 1 degree, germination decreased by 7 %. At the stage of preparation for storage, maize grain should be cleaned to purity of 93–97 % by removing grain impurities. An effective method for this is fractional separation of grain. Conclusions. Thermal insulation of metal silos significantly reduces the negative impact of fluctuations in ambient air temperature, stabilizes the storage mode, and ensures high quality maize grain. The stability of grain during storage increases in the case of selection from it a fraction of grain of small, unfilled, with a low 1000 grain weight. Key words: types of grain storage facilities, metal silo, thermal insulation, maize, quality, cleaning grain before storage

Changes in grain-filling characteristics of single-cross maize hybrids released in China from 1964 to 2014

Grain filling is the determined physiological process for the yield obtainment of cereal crops. The grain filling characteristics of 50 maize brand hybrids released from 1964 to 2014 in China were assayed across multi-environments. We found that the grain filling duration (54.46%) and rate (43.40%) at the effective grain filling phase greatly contributed to the final performance of hundred-kernel weight (HKW). Meanwhile, along with the significant increase in hundred-kernel weight (HKW), the accumulated growing degree days (GDDs) for actual grain filling period duration (AFPD) for the selected brand hybrids released between 1960s to 2010s in China had a decadal increase of 23.41°C d. However, there was a decadal increase of only 19.76°C d for GDDs of the days from sowing to physiological maturity (DPM), which was also demonstrated by the continuous decrease in the ratio between the days from sowing to silking (DS) and DPM (i.e., from 53.24% in 1960s to 49.78% in the 2010s). However, there were no significant changes in grain filling rate along with the release years of selected hybrids. Moreover, the stability of grain filling characteristics across environments also significantly increased along with the hybrid released years. We also found that the exotic hybrids showed the longer grain filling duration at the effective grain filling phase and more stability of grain filling characteristics than those of Chinese local hybrids. According to the results of this study, it was speculated that the relatively longer grain filling duration, shorter DS, the higher grain filling rate, and steady grain filling characteristics would contribute to yield improvement of maize hybrids in the future.

THERMALSTRUDING AS AN APPROACH TO GRAIN PROCESSING AND STORAGE

The need to maintain the thermal stability of grain at the stage of its elevator, often many hours, drying and subsequent storage limits the possibility of intensifying these processes. Shaft, column, drum and other dryers, modern granaries are bulky and energy-intensive, weakly or not at all connected with the subsequent stages of grain processing, which, in turn, are lengthy and multi-stage, which often leads to a decrease in the quality of the final product. For a cardinal solution to this problem, it is proposed to deliberately violate its thermal stability already at the stage of post-harvest drying of field grain, using the method of thermal trudging - high-speed heating, drying and explosion (swelling) of grain during its high-temperature processing in oncoming jets for 3-5 seconds. The product of thermal trudging is strudate, a grain in which raw starch is converted into dextrins and sugars, while it is disinfected from harmful inhibitors while maintaining the microelement and vitamin composition. Thus, the process of elevator drying and expensive storage of grain is replaced by thermal trudging with simplified (without drying and ventilation) floor storage of grain and obtaining a finished product of high quality or a semi-finished product used in flour-grinding, alcohol, oil-fat, and other technologies. Implementation of a new approach to the processing and storage of grain is possible on the basis of the developed technology of thermal trudging. Pilot-industrial and industrial thermal struders of two types have been created - autonomous and satellite, re-equipped on the basis of the reconstruction of standard grain dryers. In the article, various modifications of thermostruders and the principle of their work are considered. Long-term operation of thermal struders operating on flue gas heat carriers, hot air, superheated water vapor with a previously unattainable temperature up to +600 °C (even without a special task of grain drying) showed high economic efficiency, which increases when field grain is burrowed with high humidity. The versatility of thermostruders allows the use of heat-labile modes of high-intensity drying for seed grains as well.

Assessment of storage losses and comparison of underground and aboveground storage for better stability and quality of maize (zea mays l.) and sorghum (sorghum bicolor l.) grains in selected districts of jimma zone, Ethiopia

Production and marketing of cereal grains is one of main activities in low income countries farming system. However, yields are very low due to several factors associated with traditional practices. Despite low productivity, the postharvest loss (PHL) of grains mainly during storage is high due to storage pests. The study was conducted to assess storage related losses of grains (maize and sorghum) and compare aboveground and underground storage methods to minimize losses associated with traditional storage structures. In first phase of the study, base line data were collected using focus group discussion, key informants interview and semi-structured questioners. In the second phase, underground and aboveground storage methods were investigated along with their control for better stability of stored maize and sorghum. The survey result showed that, storage related losses (due to different factors) of maize and sorghum were 14.2 and 11.5% respectively. The major identified causes of losses were storage pests and losses due to seepage. In the second phase, from studied storage structures, grains stored in pit storage with PVC layer showed superior stability and quality in terms of prevention of pest attacks and proximate composition, respectively. The study demonstrated that, underground storage method supported with PVC lining was efficient in terms of enhancing storage stability of grains with required quality for consumption or marketing.

A general mechanism of grain growth-Ⅱ: Experimental

The formed microstructure inside polycrystalline materials strongly influences their practical performances, which process is mostly dominated by grain growth behaviors. However, the general evolution of grain growth behaviors, especial for the occurrence of abnormal grain growth and stagnant growth, remains ambiguous despite decades of efforts. Here, we investigate systematically the general evolution of grain growth behaviors by combining a new grain growth theory with grain growth experiments in SrTiO3 polycrystalline materials. The results demonstrate that the observed evolution of grain growth behaviors is in accord with the theoretical predictions, which reveals that the abnormal and stagnant behaviors of grain growth may intrinsically occur in polycrystalline systems due to the existence of non-zero step free energy for grain growth. Furthermore, the general growth theory reveals that normal grain growth results from the roughening transition of grain boundaries which corresponding to step free energy equal to zero. Besides the lower GB energy as commonly believed, the narrower grain size distribution is revealed to play an important role on the thermal stability of grains, which may lead to the counter-intuitive phenomenon of smaller nano-sized grains with higher thermal stability as recently reported in the literature. The general, quantitative growth theory may offer an accurate guidance for the microstructural design with optimal physical properties in polycrystalline materials.

Response of different electron beam melting produced Alloy 718 microstructures to thermal post-treatments

Electron beam melting (EBM) was used to produce Alloy 718 specimens with different microstructures (columnar, equiaxed and a combination thereof) by varying the process parameters. The present study aimed at assessing the response of such varying as-built microstructures to identical thermal post-treatments, which included hot isostatic pressing (HIPing) followed by heat treatment involving solution treatment and aging. The effect of these treatments on defect content, grain structure, hardness and phase constitution in the specimens was specifically analysed. Despite differences in defect content of as-built specimens with distinct microstructures, HIPing was effective in closing defects leading to samples exhibiting similar density. After HIPing, grains with equiaxed morphology or columnar grains with lower aspect ratio showed higher tendency for grain growth in comparison to the columnar grains with higher aspect ratio. The various factors affecting the stability of grains during HIPing of builds with distinct microstructures were investigated. These factors include texture, grain size, and secondary phase particles. The carbide sizes in the different as-built samples varied but were found to be largely unaffected by the post-treatments. Solution treatment following HIPing led to greater precipitation of grain boundary δ phase in regions with coarser grains than the smaller ones. After HIPing and heat treatment, all specimens exhibited similar precipitation of γ″ phase regardless of their grain morphology in the as-built condition.

Genotype by year interaction effects on soybean morpho-productive traits and biogas production

Biodiesel and biogas are especially important sources of renewable energy in the world and in Serbia. Biodiesel is used as transportation fuel; biogas is used for production of electricity and heat. Soybean (Glycine max L.) grain is the primary source of vegetable protein for food and feed supplements, also accounts for much of the world?s bio-oil supply. Due to the development of new technologies for processing agricultural waste into energy, the rate of increase in the use of alternative fuels is significantly increasing. The aim of this study was to determine the productivity of soybeans and the possibility of obtaining biogas from soybeans in divergent years, 2017-2019. Main effects were monitored, genotypes (G), years (Y) and genotype by years interaction effects (G x Y) and were used for evaluation of soybean genotypes in different environments. Soybean varieties were tested for mass of 1000 grain (MTG), plant height (PH), grain yields (GY) and biogas yield (BY). Stability of grain and biogas yield was determined to select best genotype. Results showed that genotype and years had a significant impact on all measured variables. In all tested years, the biggest GY and BY were at genotypes G1 (2.40-4.49 t ha-1, and 461.00-641.00 m3 ha-1, respectively) and G3 (1.97-4.30 t ha-1; i.e. 447.67-620.00 m3 ha-1). Genotype G2 had statistically significantly lower values for all tested parameters compared to other tested genotypes. Correlation analysis of some chosen traits showed different interdependence between measured variables depending on the year conditions. The results of this study pointed out that among best genotypes for production of grain and biogas were G1 and G3. From the results of this study it can be concluded that G x Y trials are important for evaluation of stability and choosing the most stable genotypes of soybean.

Genotype-Environment Interaction: Trade-Offs between the Agronomic Performance and Stability of Dual-Purpose Sorghum (Sorghum bicolor L. Moench) Genotypes in Senegal

Introducing sorghum (Sorghum bicolor L. Moench) genotypes into new environments is necessary for expanding the production of food and fuel, but these efforts are complicated by significant genotype × environment interactions that can reduce their effectiveness. This study set out to thoroughly analyze genotype × environment interactions and assess trade-offs between the agronomic performance and the stability of grain and biomass yields of ten contrasting genotypes under Sudano-Sahelian conditions. Experiments were carried out in a randomized complete block design with four replicates. They were conducted from 2013 to 2016 in Bambey, Sinthiou Malem and Nioro du Rip in Senegal. The joint analysis of variance revealed a highly significant effect (p < 0.0001) of genotypes (G), environments (E) and G × E interaction. Most genotypes showed specific adaptations. The best grain yields were obtained by the Nieleni and Fadda hybrids, while the improved varieties IS15401 and SK5912 were best for biomass production. An Additive Main effect and Multiplicative Interaction (AMMI) analysis showed that good grain yields were associated with environments having good soil fertility and good rainfall, while biomass yields were more influenced by the sowing date and rainfall. Similarly, we were able to confirm for our 10 sorghum genotypes that yield stability was generally associated with low performance, except for the Nieleni and Fadda hybrids, which performed well for grain and biomass production regardless of the environment. The Senegalese control genotype, 621B, showed particular susceptibility to growing conditions (soil), but remained very productive (more than 3 tons per hectare) under good agro-pedological conditions. These results lead us to recommend the Fadda and Nieleni hybrids for the entire study region, while 621B can also be recommended, but only for highly specific environments with good soils.

Variation in Nutritional and Shelf Life Parameters Among Rabi Sorghum Cultivars and Effect of Processing on These Parameters

Variation in grain mineral contents, proximate composition, shelf stability parameters, and vitamins of eight rabi grain sorghum cultivars and effect of processing (dehulling and parboiling) on these parameters were investigated. Wide variations were observed among the rabi cultivars tested for different nutritional and shelf stability parameters. Parboiling process resulted in increase of grain calcium and zinc. Dehulling resulted in significant loss in all grain minerals tested. Grain proximate compositions such as carbohydrate, proteins and vitamins like thiamine, niacin, and folic acid also showed significant increase in the parboiled-dehulled sorghum compared to raw sorghum, indicating the possible nutritional benefits that can be exploited from parboiling in sorghum. Alcoholic acidity, an important parameter to assess the shelf stability of grain, gradually increased from 0.08 and reached 0.18 at 90th day of storage period, giving indication that grain samples can be stored for 90 days without much loss due to deterioration. Alcoholic acidity of parboiled grains were in a range between 0.07 and 0.08 even at 90th day of storage period indicating positive role of parboiling in improving shelf stability of sorghum grains. Water activity for raw and parboiled sorghum for both raw and parboiled sorghum was within the limits at the 90th day of storage period.

Dynamics of correlation relationship changes in new winter wheat varieties (<em>Triticum aestivum</em> L.) under the influence of environmental factors in the Southern Forest-Steppe zone of Ukraine

Purpose. To establish correlation dependence of influence of such factors as seeding rate, sowing time and seeding methods on yield indicators, as well as individual response of winter wheat varieties to them in case of the ecological system of seed production, that would allow to form elements of intensive varietal technology and obtain the genetically determined productivity potential of the variety in the future. Methods. Weight measuring was used to determine seed yield; the reliability of the experiment results was identified by statistical evaluation, analysis of variance and regression procedure. Results. During the period of investigation, the weather conditions differed significantly both for the temperature regime and the amount of precipitation, but the stability of grain and seed yield over years was the main requirement to varieties, that allowed to study the intergenotypic correlation relationships of crop yield indices and the dynamics of their changes under the effect of ecological factors. In the course of investigation, winter wheat yield indices were fixed annually from 684 plots, which were grouped and analyzed for factors of influence in order to ensure the complete certainty. Conclusions. Variants of investigation were defined for the certified seed yield and environmental factors (sowing time and seeding method, seeding rate), that had strong positive correlation relationships. Seeding rate and seeding method had the greatest impact on 1000 kernel weight. For tille­ring coefficient, varieties depending on the variant of the investigation had a negative close correlation relationship, which was greatly affected by seeding rate. For correlation relationships, winter wheat varieties ‘Bohdana’ and ‘Slavna’ appeared to be the most stable, ‘Chorniava’ and ‘Astarta’ were the most plastic.

Stability of grain-refined reversed structures in a 301LN austenitic stainless steel under cyclic loading

Austenite stability against the deformation induced α′-martensite (DIM) formation and the cyclic deformation behavior of grain-refined structures with the grain size between 13 and 0.6µm under fatigue loading were investigated in a 301LN Cr-Ni austenitic stainless steel. The DIM transformation in the course of cycling at constant total strain amplitudes of 0.4% and 0.6% was recorded by magnetic measurements and microstructures examined by electron backscatter diffraction and X-ray diffraction. The cyclic deformation behavior was followed by the evolution of the stress amplitude. The results evidenced that the austenite stability increases with the decreasing average grain size down to about one micrometer, obtained in annealing at 900°C for 1s. On the contrary, the stability decreases drastically in the submicron, non-homogeneous grain structures created at the lower temperatures of 800–700°C. In these structures, submicron grains seem to be stable, and the precipitation of CrN is considered to contribute to the reduced stability of grains with a few-micron-size present among submicron grains. Under cyclic loading, the level of initial stress amplitude varied considerably in dependence on the refined austenite grain size. At the 0.6% strain amplitude, the initial softening was followed by cyclic hardening. The level of the final stress amplitude was related to the fraction of DIM formed during cycling straining.

Response of new varieties of winter wheat (Triticum aestivum L.) to the impact of environmental factors under the conditions of the Southern Forest-Steppe zone of Ukraine

Purpose. To define the level of impact of such factors as rate, time and methods of sowing on seed productivity and certified seeds, and the individual response of winter wheat varieties to these factors if used the ecological system of seed farming, that would allow to form and obtain genetically determined potential of variety productivity.Methods. Weight measurement for determining seed yield; statistical, variance and regression analysis for identifying the reliabi­lity of the experiment results.Results. During the research period, weather conditions were greatly differed both by temperature regime and precipitation, but stability of grain and seeds yield on an annual basis was the main requirement to varieties. During the study of «grain productivity» value and quantitative indices of winter wheat yield structure, the results from 684 plots were obtained which were grouped and analyzed for impact factors for complete certainty, and NIR0,05 was calculated.Conclusions. Thus, in case of shifting sowing time from optimum to later period, efficiency of water use by plants was decreasing to a greater extent during years with insufficient precipitation. The shift of sowing time to later period providing optimal seeding rate and row seeding method did not reduce yield. The yield of winter wheat varieties to be studied when sowing in usual manner with seeding rate of 5,5 million seeds/ha in the period from September 15 and October 5 was the highest. Varieties ‘Slavna’ and ‘Chorniava’ provided the highest grain productivity for seeding rate of 5,5 million seeds/ha and using row seeding method, with slight impact of sowing time factor. Grain yield of studied varieties showed negative response during the experiment when seeding rate decreased up to 2,5–3,0 million seeds/ha. ‘Astarta’ varie­ty provided the highest productivity for certified seeds yield as compared to the control (from 1,59 to 3,38 t/ha). The variant of the experiment when sowing on October, 5 in usual manner with seeding rate of 5,5 million seeds/ha showed the highest productivity of 7,02 t/ha (+3,38 t/ha, or +92,9%). Shifting of sowing time for October, 5 resulted in a significant decrease in yields of certified seeds as compared to sowing time on September 15 and 25. Seed yield of studied varieties when sowing on October, 5 was higher than in case of sowing on September, 25. The highest percentage of certified seeds output in the studied varieties was observed for a seeding rate of 2,5–3,0 million seeds/ha. For seeding rate of 5,5 million seeds/ha for varieties with seeding time between September 15 and 25, the difference in grain yield was negligible. The winter wheat variety ‘Astarta’ provided the highest yield of seeds during the research years – 9,36 t/ha, the standard variety ‘Bogdan’ – the lowest one in the best variant of 5,55 t/ha.

Impurity stabilization of nanocrystalline grains in pulsed laser deposited tantalum

Abstract

Impact of sedimentology, diagenesis, and solid bitumen on the development of a tight gas grainstone reservoir in the Feixianguan Formation, Jiannan area, China: Implications for gas exploration in tight carbonate reservoirs

Tight gas grainstone reservoirs in the third member of the Feixianguan Formation, Jiannan area, evolved from a paleo-oil accumulation as evidenced from abundant solid reservoir bitumen. Porosity evolution of the grainstones was studied by evaluating relative influences of sedimentology, diagenesis, and solid bitumen formed during cracking of accumulated oils. Grainstones exhibited regional-distinct effectiveness for paleo-oil and present-gas accumulations during oil window and subsequent gas window diagenesis. In the southern zone where grainstones were not subjected to subaerial exposure and meteoric diagenesis in the early diagenetic stage, paleoporosity at the time of oil charge was mainly controlled by sedimentologic factors (e.g., grain size, sorting, and grain type), and paleo-oil reservoirs only occurred in the ooid-dominated grainstones with good sorting and coarse grain size. In contrast, in the northern zone meteoric diagenesis was responsible for paleoporosity preservation due to the early mineral stabilization of grains and meteoric calcite cementation, which caused grainstones greater resistance to compaction. Hence, most of the grainstones in the northern zone, regardless of textural variables, formed effective reservoirs for paleo-oil accumulation. As the oil cracked to gas with increasing depth and temperature during the late oil window and initial gas window, solid bitumen occluded reservoir pores to varying degrees and caused paleo-oil reservoirs to be significantly heterogeneous or completely ineffective for gas accumulation. In contrast, most grainstones that were once ineffective oil reservoirs transformed into effective gas reservoirs due to no or minor influence of solid bitumen precipitation. The model of reservoir transformation development of tight grainstones provides a plausible explanation for key observations concerning the diagenetic and distribution differences between paleo-oil and present-gas reservoirs. It is useful in predicting the distribution of potential reservoirs in carbonate strata in future exploration.

PERFORMANCE AND STABILITY OF SOME BREAD WHEAT GENOTYPES FOR GRAIN YIELD, PROTEIN AND GLUTEN CONTENTS UNDER DIFFERENT ENVIRONMENTAL CONDITIONS

Seventeen genotypes (G) of bread wheat (14 promising lines and 3 commercial cultivars) were evaluated for mean performance and stability of grain yield/plant, grain protein content and dry gluten percentage under 16 environments (two locations (L), two sowing dates(D) and four fertilization treatments (F)). The resultsconfirmed the existence of considerable genetic variation among genotypes and their performance was significantly affected by different environments for the studied traits. Kalubia locations recorded the highest mean values for grain yield/plant while; Fayoum location recorded the highest mean values for the two quality traits. Yield and quality traits were significantly increased on early (recommended) sowing dates at Kalubia and Fayoum locations than on late sowing dates. Applying biofertilizer only gave the lowest mean performance in all traits, but adding mineral N besides biofertilizer markedly increased grain yield/plant and the two quality traits. However, insignificant differences existed between the rate of nitrogen recommended (80kg N/fed.) and the rate of (biofertilizer + 60kgN/fed.), indicating that biofertilizer could be efficient in reducing costs of the expensive mineral N and reducing environmental pollution. On an average highest values of grain yield/plant were recorded by the promising wheat lines no. 10 (24.57 g), no. 9 (22.50 g), and no. 11 (21.64 g) as compared to the best check cultivar Giza 168. Meantime, this cultivar surpassed the other genotypes in protein and dry gluten percentages. Concerning phenotypic stability, the three superior lines no. 10, 9 and 11 gave the highest mean values (x¯) of grain/plant coupled with significant regression coefficient (bi) values higher than unity and significant deviation from regression (S2di), thus they considered specifically adapted to favourable environments.

High‐Yield Maize Production in Relation to Potassium Uptake Requirements in China

Understanding maize (Zea mays L.) grain yield in relation to K uptake requirements is essential for devising optimized K fertilizer management practices and agricultural policies to increase grain yield for food security. A database comprising 953 measurements was created using 56 on‐farm and research station experiments during 2000 to 2012 in the North China Plain (NCP) to determine K uptake requirements and patterns of K accumulation pre‐ and post‐silking with different yield levels. The K requirement Mg−1 grain yield (Kreq.) in the K = Opt. treatment was 15.0 kg, which was lower than 20.0 kg in the K > Opt. treatment. In the Optimal K treatment, average Kreq. values were 15.0, 14.8, 14.8, and 15.7 kg for grain yields ranging from <8.0, 8 to 10, 10 to 12, and >12.0 Mg ha−1, respectively. The relative consistency of Kreq. values with increasing grain yield was mainly attributed to an offset in the increase in stover K (from 14.0 to 18.1 g kg−1), an increase in harvest index (HI) from 0.49 to 0.54, and the stability of grain K concentrations (about 3.2 g kg−1). Higher percentages for K accumulation at the post‐silking stage were observed with >12 Mg ha−1 (24%) and 10 to 12 Mg ha−1 (22%) compared to <10 Mg ha−1 (9%). In conclusion, maintaining adequate K supply and post‐silking K accumulation is essential for achieving high‐yield maize production.