critical limit
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2021 ◽  
Vol 14 (1) ◽  
pp. 167
Author(s):  
Mamunur Rahman ◽  
Mohammad Mofizur Rahman Jahangir ◽  
Mohammad Golam Kibria ◽  
Mahmud Hossain ◽  
Md Hosenuzzaman ◽  
...  

The critical limit for zinc (Zn) varies from 0.38 to 2 µg/g soil depending on the crop and soil type. However, the critical limit for Zn was not explored recently for rice and potato cultivation in the floodplain soils of Bangladesh. A pot experiment was conducted to determine the critical limits of Zn in soil and plants for rice and potato cultivation in two agro-ecological zones (AEZs) of Bangladesh. The soil samples were collected from 20 different locations of Old Brahmaputra and Active Ganges Floodplains with low (<0.9 µg/g), medium (0.91–1.80 µg/g) and high (>1.80 µg/g) Zn status. The experiment was laid out in a factorial and completely randomized design with two levels of Zn (Zn0 and Zn1 (0 and 4.87 kg/ha as Zn sulphate)) applied to 20 different soil samples for rice and potato cultivation using three replications. The critical limit of Zn was determined through a graphical and statistical approach and crops were harvested at the stem elongation (for rice) and tuber filling (for potato) stage. The critical limit of Zn in soil for rice was found to be 0.8 and 0.85 µg/g by graphical and statistical methods, respectively, and both methods revealed the same value (0.73 µg/g) for potato. The critical limit of Zn in rice plants was 23.9 and 24.32 µg/g, whereas in potato plants it was 27.1 and 26.61 µg/g, determined by graphical and statistical methods, respectively. The added Zn supply in soil significantly increased the dry matter accumulation in rice (by 5.6%) and potato (by 10%) compared to no Zn supply. Therefore, a significant positive response to added Zn could be observed on crop growth and yield when the Zn concentration remained below the mentioned critical level for rice and potato cultivation in floodplain soils of Bangladesh.


2021 ◽  
Vol 119 (6) ◽  
pp. 87-97
Author(s):  
LAPTIEVA Viktoriia ◽  
VAVDIICHYK Iryna ◽  
LAPTIEV Oleksandr

Background. One of the main indicators of the country's economic development is its trade balance, in particular the total size and value of products that the country can adequately represent in foreign markets, ensuring reliable cash flow, balanced development of economic sectors, and, consequently, growing greatness and prosperity. In modern conditions, ensuring such a global export expansion of Ukrainian products to foreign markets, in particular European ones, is impossible without proper innovation of producers and exporters, as well as sufficient investment in planned innovation projects, which requires in-depth economic analysis and strategy in this direction. Using the latest scientific inventions and research. The aim of the article is to study and analyze the current state of Ukrainian exports to world and European markets and substantiate the possibility of differentiation of export flows in order to evenly distribute the share of exports between all industries, including engineering and high technology, etc. and move away from raw materials Materials and methods. The theoretical and methodological basis of the article is the scientific works of Ukrainian and foreign scientists on the problems of innovation development. Results. As we can see from the researched data, during the last decade there is a tendency of prevalence in the general structure of the country's exports of ferrous metallurgy and mining, which is primarily due to the strong potential of these industries inherited from Soviet times, as well as agro-industrial products. in particular, cereals and oils, which is explained by the tradition of these industries for the economy of Ukraine, and established under the Association Agreement tariff quotas for Ukrainian agricultural products in the markets of the European Union. Revolutionary tasks have been set to reduce the share in the structure of exports of these types of goods first to the critical limit of 10%, and then to the target of 5%, while maintaining and even increasing the absolute monetary value of exports of these goods, which is possible only if increasing exports by other product groups, identifying priority areas among such products while legislative incentives and creating a regulatory environment to strengthen the ability of domestic enterprises to compete in world markets, especially in the face of growing protectionism in response to the challenges of the pandemic. Conclusion. Summing up, we can conclude that Ukraine has created all the prerequisites for the implementation and implementation of all short-term and strategic plans for the domestic economy and a worthy place among participants in both European and global markets, subject to improving the scientific and educational system of industrial development, wider implementation of innovation processes, as well as the implementation of plans to diversify export flows.


2021 ◽  
Vol 8 ◽  
Author(s):  
Jie Xiao ◽  
Xiang Long ◽  
Ming Ye ◽  
Haibo Jiang ◽  
Lingfei Liu ◽  
...  

The bond performance between steel bar and cement-based materials was the prerequisite for the two materials to work together, and previous studies showed that the bond behavior of the steel bars and cement-based materials will vary with the kinds of cement-based materials. For this reason, this paper adopted 12 direct pullout test specimens including three types of concrete and two types of steel bars. The strain of the steel bar at six measuring points was measured with a strain gauge. Based on the measured strain and free end slip of the steel bars, the distribution of steel stress, bond stress, and relative slip and the bond slip relation along the anchorage length were obtained and analyzed for different concrete and different steel bars. Based on these test results of steel strain and relative slip at six measuring points, the anchorage position function could be established in consideration of anchorage position, which was conducive to the establishment of an accurate bond–slip relationship. In addition, the anchorage length of the steel bar in Engineered Cementitious Composites (ECC) calculated from the equilibrium equation of critical limit state is only half of the anchorage length calculated in the current Code for Design of Concrete Structures (GB 50010-2010) in China. It is suggested to establish the critical anchorage length formula suitable for ECC in future studies.


Nativa ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 494-499
Author(s):  
Samara Deschamps Gelsleichter ◽  
Heloisa Milesky Alves Massaneiro ◽  
Andrei de Souza da Silva ◽  
Priscilla Dors ◽  
David José Miquelluti ◽  
...  

A deficiência de zinco representa um problema de saúde pública. Uma das estratégias para melhorar essa questão consiste em biofortificação agronômica. O objetivo dessa pesquisa foi avaliar o teor de Zn na parte aérea (folhas e ramos) e o limite crítico de Zn para plantas de erva-mate submetidas a adubação com sulfato de Zn. O experimento foi conduzido em casa de vegetação no município de Lages. Foi utilizado Cambissolo Háplico Distrófico Típico, o qual foi submetido a análise química (Tedesco et al., 1995) e granulométrica (EMBRAPA, 1997). O delineamento experimental utilizado foi o inteiramente casualizado. As unidades experimentais foram compostas por vasos contendo 6 kg de solo, cinco doses de Zn (0, 100, 200, 300 e 400 mg.kg-1) e sete repetições, totalizando 35 unidades experimentais. Foram realizadas análises antes da colheita (Índice SPAD, altura e Infrared Gas Analyser - IRGA) e análises após a colheita (peso fresco e seco de parte aérea, teor de Ca, Mg, P, Cu, Zn na folha). Os dados foram submetidos a análise de variância, com normalidade testada pelo teste de Shapiro-Wilk e a homogeneidade de variâncias pelo teste de Levenne, a nível de significância de 5%. A aplicação de doses crescentes de Zn ao solo resultou em aumento do teor de Zn na parte aérea de forma linear.  O teor médio de Zn na folha variou de 27 mg kg-1 na ausência de aplicação de Zn a 883 mg kg-1 na dose aplicado de 400 mg kg-1.  Não houve diferença estatística para massa fresca, seca de parte aérea, índice SPAD, altura, condutância estomática e transpiração indicando ausência de estresse oxidativo. Não foi possível calcular o limite crítico de Zn para erva-mate. Palavras-chave: biofortificação agronômica; Cambissolo; Ilex paraguariensis.   Diagnose yerba mate nutritional and photosynthetic indices under different levels of zinc fertilization   ABSTRACT: Zinc deficiency represents a public health problem. One of the strategies to improve this issue is agronomic biofortification. The objective of this research was to evaluate the Zn content in the aerial part (leaves and branches) and the critical limit of Zn for yerba mate plants submitted to fertilization with Zn sulfate. The experiment was conducted in a greenhouse in the municipality of Lages. A typical Dystrophic Cambisol was used, which was subjected to chemical (Tedesco et al., 1995) and granulometric (EMBRAPA, 1997) analysis. The experimental design used was completely randomized. The experimental units were composed of pots containing 6 kg of soil, five doses of Zn (0, 100, 200, 300 and 400 mg.kg-1) and seven replications, totaling 35 experimental units. Analyzes were performed before harvesting (SPAD Index, height and Infrared Gas Analyzer - IRGA) and analyzes after harvesting (fresh and dry aerial weight, and Ca, Mg, P, Cu, Zn content in the leaf). The data were submitted to analysis of variance, with normality tested by the Shapiro-Wilk test and homogeneity of variances by the Levenne test, at a significance level of 5%. The application of increasing doses of Zn to the soil resulted in a linear increase in the Zn content in the aerial part. The average Zn content in the leaf varied from 27 mg kg-1 in the absence of Zn application to 883 mg kg-1 at the applied dose of 400 mg kg-1. There was no statistical difference for fresh, dry shoot weight, SPAD index, height, stomatal conductance and perspiration indicating absence of oxidative stress. It was not possible to calculate the critical limit of Zn for yerba mate. Keywords: biofortification agronomic; Cambisol; Ilex paraguariensis.


Author(s):  
I.D. Duzhyi ◽  
G.P. Oleshchenko ◽  
L.A. Bondarenko

The incidence of tuberculosis in our country, according to statistics, seems to be declining. However, it should be remembered that the figures of the Crimean Autonomous Republic and the temporarily occupied territories of Donetsk and Luhansk oblasts are excluded from the digital data. Of particular concern are the significant worldwide morbidity and infant mortality rate of 700 people per day.The problem’s urgency is due to the data and the increase in the number of patients with common and destructive forms of pulmonary tuberculosis. The leading factor is the constant increase in the number of patients with multidrug­resistant conditions, the effectiveness of treatment of which does not reach 50%. In comparison, the WHO considers the critical limit for stabilizing the epidemic situation «effective treatment» at 85 %. Objective — to study the features of familial tuberculosis on the background of outpatient treatment of patients with newly diagnosed tuberculosis. Materials and methods. We observed 157 families with various forms of pulmonary tuberculosis. Radiation, bacteriological, immuno­genetic methods were used in the examination. Family members were examined every six months. Results and discussion. Among the TB contacts after this period, tuberculosis was found in 162 people. Sources of tuberculosis (157) were bacillary in 49.7 %, TB contacts — in 43.8 %. Among patients in the group of heads of tuberculosis, there were 28 (35.9 %) people on MRTB, and in the group of TB contacts — 32 (45.1 %), р < 0.05. Thus, tuberculosis’s cause in TB contacts was not isolated from the family of patients with newly diagnosed tuberculosis. Conclusions. Based on the results obtained, it is safe to say that if at least fixed bacillary patients were hospitalized, there could be no family TB contact patients. Comparing all sources of tuberculosis patients (157), it can be imagined that cases of familial tuberculosis (162) could be avoided. Nature «responded» to ignoring one part of the epidemic process (transmission of infection that increases with contact) by increasing the number of patients with familial tuberculosis by 5 people. We note: it was only about the Sumy region and only for a limited time.


2021 ◽  
Vol 34 (2) ◽  
pp. 253-266
Author(s):  
Ali H. I. Al-Bayati ◽  
AbdulKarem A. M. Alalwany ◽  
Mohammed Abdal-Mnam Hassan

The study included the analysis of (341) samples from eight pedons cover most of the prevailing sub great soil groups in Iraq, which are (Typic Torrifluvents, Typic Torrients, Typic Gypsiorthids, Typic Calciorthids, Aquollic Salorthids, Typic Chromoxerects, Typic Xerrochrepts and Typic Calcixerects) to study the pedogenetic distribution of total and bioavailable content of the manganese, zinc, copper, and iron also its relationship with some soil properties. Results showed significant differences between the studied regions of total content of microelements, the bioavailability content also showed a significant deference between the studied regions. The physical and chemical soil properties clearly affected on their content of micronutrient and 77% of the studied samples were below the critical limit for zinc, but 65% of the studied samples were under the critical limit for iron. This refers to the response of the cultivated crops in such sub great soil groups to the addition of Zn and Fe fertilizers, also pedogenetic distribution of the content of these microelements showed a decrease with depth and compatible with the distribution of each of the separated clay and organic matter and decrease with the increase in the soil content of calcium carbonate.


2021 ◽  
Author(s):  
Dhanasekaran Linga Prabu ◽  
Pananghat Vijayagopal ◽  
Sanal Ebeneezar ◽  
Chellappa Kalidas ◽  
Palsamy Rameshkumar ◽  
...  

Abstract In a feeding experiment, cottonseed meal (CSM) was used to replace fishmeal (FM) in the diet of snubnose pompano supplemented with lysine and methionine to assess the growth, nutritive profile, hematological, histological and stress biomarkers response. Experimental fishes were randomly stocked in five treatments each with triplicates. Five isonitrogenous and isolipidic diets with graded level of CSM (0, 8.7, 17.4, 26.0 and 34.7%) as replacement for FM protein (0, 25, 50, 75, and 100%) were formulated and fed to respective treatments. Comparison between various parameters among the treatments was made using orthogonal polynomial contrasts to indicate the statistical significance. Higher alkaline phosphatase, acid phosphatase, lactate dehydrogenase, malate dehydrogenase, aspartate and alanine aminotransferase activities were observed in 0CSM group and followed by 100CSM group as higher inclusion level of CSM with higher free gossypol content did not affect the metabolic enzyme activities. The maximum muscular free gossypol accretion of 1.28 mg kg-1 (on wet basis) was recorded in 100CSM group which was very well below the critical limit set by FDA. As a conclusion, fishmeal can be completely replaced using cottonseed meal in the diet of pompano without adverse effect on growth, metabolism and general health.


2021 ◽  
Vol 2114 (1) ◽  
pp. 012024
Author(s):  
Sundus A. Abdullah ◽  
Tabbark R. Aziz

Abstract The present study aims at assessing the status of heavy metals such as nickel, cadmium and lead to pollute some areas of Baghdad city. In this study the spectral absorption device and the program ArcGIS 10.2 will using. The soil samples were taken from five different locations in Baghdad, including Ameriya, Kadhimiya, Palestine Street, Jadiriyah and Taji for the 5cm depth layer on both sides of the road. This work on soil samples has been completed in two :phases 1 - Preparation of samples: For the purpose of converting solid material into a extract containing elements in the form of single ions can be estimated by the device 2-Determination of elements: Samples prepared to the device for the purpose of estimating their concentration in PPM units using the Atomic Absorption Spectrometer. The findings of this study can be summarized as follows: 1-The results showed that nickel concentrations ranged from 0.0336-0.1512 ppm where the lowest value of nickel was found in Kadhimiya by 0.0336 and the highest value was found in Ameriya with a value of 0.1512 and it is considered to be a non-polluting nickel in these areas because it did not exceed the critical limit 1.3 ppm. Which was explained by GIS using the map of Baghdad and determine the area studied. The results were distributed by the interpolation method using ArcGIS 10.2 program, it was noticed that there are high pollutant values in an area considered agricultural according to the classification of human settlements, which is the Jadiriyah area, where Lead (Pb) element showed a strange behaviour by its presence in high values in Jadiriyah, where its source is unknown. A future research will be prepared to study the sources of these pollutants for treatment.


Author(s):  
Emil Eriksson ◽  
Joel Andersson ◽  
Magnus Hörnqvist Colliander

AbstractIn alloys where carbides are the main grain boundary phase, the role of carbides during hot working is not known. Here, we address the effect of grain boundary carbides on the dynamic recrystallization during hot compression of Ni-base superalloy Haynes 282. When excluding variations from experimental factors neither stress evolution nor final microstructure indicated that carbides exerted a significant influence on the dynamic recrystallization. The carbide solvus temperature is not a critical limit during thermomechanical processes.


Author(s):  
Ksh. Newton Singh ◽  
Shyam Das ◽  
Piyali Bhar ◽  
Monsur Rahaman ◽  
Farook Rahaman

We present an exact solution that could describe compact star composed of color-flavor locked (CFL) phase. Einstein’s field equations were solved through CFL equation of state (EoS) along with a specific form of [Formula: see text] metric potential. Further, to explore a generalized solution we have also included pressure anisotropy. The solution is then analyzed by varying the color superconducting gap [Formula: see text] and its effects on the physical parameters. The stability of the solution through various criteria is also analyzed. To show the physical validity of the obtained solution we have generated the [Formula: see text] curve and fitted three well-known compact stars. This work shows that the anisotropy of the pressure at the interior increases with the color superconducting gap leading to decrease in adiabatic index closer to the critical limit. Further, the fluctuating range of mass due to the density perturbation is larger for lower color superconducting gap leading to more stable configuration.


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