optimal ratio
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2022 ◽  
Vol 12 (1) ◽  
pp. 170-176
Author(s):  
Victoria Samokhina ◽  
Olena Shpak ◽  
Valentyna Pasynok

The article explores the ecological essence of English-speaking discourse as optimal ratio of phatic and informational content in contacts of addressants and addresees in different spheres of communication. Unison and dissonant contacts are distinguished as ecological and non-ecological communicative contacts. The set of standards and rules of verbal and non-verbal behavior in English society organizes and regulates communicative process. The type of situation and the addressee are leading factors on three stages of contact: establishing, maintaining and breaking. The findings are supported with the examples taken from the English discourse.


2022 ◽  
Vol 42 ◽  
pp. 04004
Author(s):  
K.A. Vorobev ◽  
T.S. Orlova ◽  
L.N. Safiullin

In this article, the authors consider the problem of ensuring food security of territories as one of the areas of sustainable economic development. The authors' studies have shown that solution to this problem largely depends on the regulation at the state level of individually balanced human nutrition in order to ensure the optimal ratio of the components necessary for life.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yaobin Li ◽  
Xin Guo ◽  
Sheng Xue ◽  
Chun-Shan Zheng ◽  
Maoliang Shen ◽  
...  

To improve the borehole sealing effect, especially that of coal seam with low permeability and micro fissures, this paper takes the expansion rate of the sealing material as the response value and establishes the quadratic model embracing the expansion rate and various experimental factors by designing orthogonal experiments. The response surface is used to further determine the significance order of each key factor according to the expansion rate and adjust the admixture content to obtain the optimal ratio of the sealing material. For the research investigating a sealing material, the optimal ratio of the sealing material is obtained: the content of water reducing agent of 0.5%, the content of retarder of 0.04%, water-cement ratio of 0.8, and the content of expansion agent of 10%. At this time, the expansion rate reaches 3.136%. Besides, a scanning electron microscope is used to observe the microscopic morphology of the material. According to the scanning electron microscopy analysis of new borehole sealing materials, the surface of the new borehole sealing material shows no holes and possesses compactness; and a large amount of ettringite is formed on the surface of the hydration product of hardened cement slurry. The ettringite improves the expansibility of the material. The new sealing material provides a new idea for gas sealing, which is of great significance to improve the efficiency of borehole extraction, improve the utilization rate of resources, and prevent gas accidents.


Author(s):  
М.А. Ковалёва ◽  
Т.Н. Виниченко ◽  
В.Г. Шрам ◽  
Е.Г. Кравцова ◽  
М.А. Плахотникова

Одним из наиболее серьёзных осложнений при добыче и транспортировке нефти является интенсивное выпадение асфальто-смолистых и парафиновых отложений (АСПО). В данной работе проводилась оценка эффективности растворителей разной химической природы для удаления АСПО. На основании лабораторных данных были сделаны выводы о использовании неиногенного типа ПАВ, спиртов с различной молекулярной массой, оптимального соотношения алканового и ароматического компонента для растворения АСПО парафинового типа. One of the most serious complications in oil production and transportation is the intensive deposition of as-falto-resinous and paraffin deposits (ASPs). In this work, the effectiveness of solvents of different chemical nature for the removal of ASPs was evaluated. Based on laboratory data, conclusions were drawn about the use of noninogenic surfactants, alcohols with different molecular weights, and the optimal ratio of the alkane and aromatic components for the dissolution of paraffin-type ASPs.


2021 ◽  
Vol 213 ◽  
pp. 105875
Author(s):  
Xitao Yang ◽  
Zhizhao Duan ◽  
Yuhua Hu ◽  
Jincheng Liu ◽  
Yanchun Xu ◽  
...  

2021 ◽  
Vol 1205 (1) ◽  
pp. 012005
Author(s):  
B Smirova ◽  
M Sedlacik ◽  
R Novotny

Abstract This paper deals with the use of calcinated clay and micronized limestone as supplementary cementitious materials (SMCs) for preparation of blended Portland cement CEM II/B-M (Q-LL). Clay used in this study was calcinated at 700°C and pozzolanic activity after calcination was assessed using accelerated R3 pozzolanic test and modified Chapelle test. The influence of calcinated clay and limestone addition on mechanical properties and hydration process was investigated and an optimal ratio for 35% clinker replacement was found. Initial decrease of mechanical strength at early ages, caused by SCM addition, was almost compensated during maturation of the binder.


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Yunhua Luo ◽  
Ogheneriobororue Amromanoh

Background. Bone mineral density is widely used by clinicians for screening osteoporosis and assessing bone strength. However, its effectiveness has been reported unsatisfactory. In this study, it is demonstrated that bone organic-inorganic phase ratio is a fundamental determinant of bone material quality measured by stiffness, strength, and toughness. Methods and Results. Two-hundred standard bone specimens were fabricated from bovine legs, with a specialized manufacturing method that was designed to reduce the effect of bone anisotropy. Bone mechanical properties of the specimens, including Young’s modulus, yield stress, peak stress, and energy-to-failure, were measured by mechanical testing. Organic and inorganic mass contents of the specimens were then determined by bone ashing. Bone density and organic-inorganic phase ratio in the specimens were calculated. Statistical methods were applied to study relationships between the measured mechanical properties and the organic-inorganic phase ratios. Statistical characteristics of organic-inorganic phase ratios in the specimens with top material quality were investigated. Bone organic-inorganic phase ratio had strong Spearman correlation with bone material properties. Bone specimens that had the highest material quality had a very narrow scope of organic-inorganic phase ratio, which could be considered as the “optimal” ratio among the tested specimens. Conclusion. Bone organic-inorganic phase ratio is a fundamental determinant of bone material quality. There may exist an “optimal” ratio for the bone to achieve top material quality. Deviation from the “optimal” ratio is probably the fundamental cause of various bone diseases. This study suggests that bone organic-inorganic phase ratio should be considered in clinical assessment of fracture risk.


2021 ◽  
Vol 56 (3) ◽  
pp. 1144-1151
Author(s):  
Kaori Isawa ◽  
Hiroko Watanabe ◽  
Yudai Honma ◽  
Kotaro Imai
Keyword(s):  

2021 ◽  
Author(s):  
Junzhen Di ◽  
Yangyang Jiang ◽  
Mingjia Wang ◽  
Yanrong Dong

Abstract Aiming at the problems of insufficient supply of carbon source and toxic effect of heavy metal ions in the treatment of acid mine wastewater (AMD) by sulfate reducing bacteria (SRB), immobilized particles were prepared with Rhodopseudomonas spheroides, SRB and lignite as the main raw materials, and the optimal ratio of immobilized particles was determined based on single factor test and orthogonal test. The adsorption experiment of immobilized particles was carried out under the optimal ratio, the reaction kinetic process and adsorption capacity of immobilized particles for different ions were analyzed, and the action mechanism was studied. The results show that lignite not only has good adsorption performance, but also can be used as the carbon source of SRB after degradation by Rhodopseudomonas spheroides, so as to solve the problems of low removal efficiency of AMD by SRB and insufficient supply of carbon source. When the dosage of lignite, Rhodopseudomonas spheroides and SRB is 3%, 10% and 10% respectively, and the particle size of lignite is 200 mesh, the overall treatment effect is the best. The removal rates of SO42-, Zn2+ and Cu2+ are 83.21%, 99.59% and 99.93% respectively, the pH is increased to 7.43, the release of COD is 523 mg/L, and the ORP number is -134 mV. The reduction process of SO42- by immobilized particles conforms to the pseudo first-order kinetics, the isothermal adsorption of Zn2+ more conforms to the Freundlich isothermal adsorption equation, and the adsorption kinetics of Zn2+ more conforms to the pseudo second-order kinetic model.


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