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2021 ◽  
Vol 54 (2F) ◽  
pp. 131-144
Author(s):  
Saif Rmaidh ◽  
Salih Awadh

The research aims to assess the claystone exposed in the Nfayil Formation (Middle Miocene) for Portland cement (P.C.) manufacturing based on mineralogy and geochemistry. The importance of the study is to avoid the miming of the agricultural soils that are mining now for the cement industry. Claystones of Nfayil Formation and the limestone of the Euphrates Formation were used to design the raw mixture as clay to limestone (1:3). The chemical composition (%) of the designed mixture was calculated using the Alligation Alternative Method (A.A.M.) as CaO (65.52), MgO (1.05), SiO2 (21.65), Al2O3 (7.43), Fe2O3 (2.62), Na2O3+K2O (1.52) and SO3 (0.26), which are suitable for P.C. The lime saturation factor (LSF = 92.8), silica saturation factor (SSF = 0.87), alumina ratio (AR = 2.8), silica ratio (SR = 2.16), and calcium to silica (CS = 3.04) of the planned mixture are all within the permissible range. A clinker was successfully manufactured as composed mainly of belite, alite, aluminate, and ferrite.



Author(s):  
Abbad Nofal Kassouha, Raeed Solyman Muhammad, Moustafa Hussi Abbad Nofal Kassouha, Raeed Solyman Muhammad, Moustafa Hussi

The casting technology is one of the most important production processes, because of its special characteristics and features such as the ability to produce complex shapes and a wide range of compositions. This work aims to study several mixtures of sand with different structures in terms of permeability, strength, thermal expansion coefficient, comparing them, study the effect of the elements involved in the composition of these mixtures on those parameters, and create a database that can be used both in modeling processes or mold design, as when designing the sand mold The value of the sand expansion of the mold must be taken into account, otherwise the designer will face the problem of the possibility of exit some dimensions of the final product from the permissible range and thus rejecting the product, Or the product is undergone to deformations resulting from the expansion of mold sands, which must be avoided when designing the mold Knowing the characteristics of those sand mixtures helps the investor in choosing the most appropriate mixture for the required casting process in terms of engineering specifications or quantity, with the aim of less costly production by saving in choosing the most appropriate and least expensive sand mixture that serves the desired purpose.



2021 ◽  
Vol 9 (2) ◽  
pp. 42-45
Author(s):  
Hanaa A. Muhammad ◽  
Khalid N. Sediq ◽  
Kwestan H. Sdiq

Recently, bottled water consumption has been increasing significantly, even when the quality of tap water is considered excellent, which contributes to plastic pollution. Besides, reducing the use of plastic generally is recommended world widely, as its consumption is in an alarming rate. Therefore, this study aims to compare the tap and bottled water and manifest the reasons behind choosing the bottled water, which is less comfortable and often more expensive over the tap water. In this study, samples have been taken from both bottled and tap water in Koya city from November 2020 to May 2021 to test their quality using PH, DO, EC, and TDS meter, hardness was determined by complexometric titration method at 21°C, and XRF spectrometers. According to the quality standards, most of the variables were in a permissible range, except for dissolved oxygen and Aluminum content in both types of water and TDS for two types of bottled water. However, the quality of tap water was much safer to be used, as compared with the bottled water. 



Author(s):  
G.K. Smirnov ◽  
S.V. Reznik ◽  
A.R. Gareev ◽  
A.D. Khodnev

The purpose of the study was to select technological parameters of the production line of unidirectional thermoplastic polyphenylene sulfide-based tapes. The selection was made relying on the variation of the tape speed, the temperature of the sub-melting furnace, and the calendering module in the simulation of heat transfer processes. Modeling of heat transfer was based on the results of tests to determine the temperatures of phase transitions of a thermoplastic polymer in the composition of composite material and the dependence of the heat capacity of the composite on temperature. The indicated properties of the material were determined by analyzing the dependences obtained during differential scanning calorimetry and thermogravimetric analysis. As a result, the allowable range of distances between the polymer binder melting furnace and the calendering module was determined, which provides the necessary tape temperatures at the stages under consideration and the manufacturability of production. The permissible range of distances between the calendering module and the coiling module was also determined.



Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1541
Author(s):  
Sergey Korchagin ◽  
Ekaterina Romanova ◽  
Denis Serdechnyy ◽  
Petr Nikitin ◽  
Vitaliy Dolgov ◽  
...  

A model of a layered hierarchically constructed composite is presented, the structure of which demonstrates the properties of similarity at different scales. For the proposed model of the composite, fractal analysis was carried out, including an assessment of the permissible range of scales, calculation of fractal capacity, Hausdorff and Minkovsky dimensions, calculation of the Hurst exponent. The maximum and minimum sizes at which fractal properties are observed are investigated, and a quantitative assessment of the complexity of the proposed model is carried out. A software package is developed that allows calculating the fractal characteristics of hierarchically constructed composite media. A qualitative analysis of the calculated fractal characteristics is carried out.



Author(s):  
Arkajyoti Mitra ◽  
Joyanto Roychoudhary

With the rising cases of COVID-19 worldwide, transportation sector has been one of the primary victims of Covid-19. Our country is going through the unlocking phase and public transport is being available again. But in order to stay safe from Covid-19, the physical distancing norms must be maintained. In public transport, it is rather impossible to maintain a proper physical distance. So we have created an automatic system, where the number of people riding in the vehicle is always fixed so as to maintain proper physical distancing. This system has a fixed number of passengers who can ride at the same time. It detects the no. of passengers going inside the vehicle and stops the entry of other passengers when it reaches it’s permissible range. And until the passenger count is lessened, the entry gate won’t open. The Novel prototype model is tested using web-based simulation tool Tinker Cad Circuits and the outcomes are remarkable and can be Implemented in Real life Cases for crowd management systems.



Author(s):  
Noor Zaheer Ahmed ◽  
Hemanth Kumar Agibothu Kupparam ◽  
Seema Akbar ◽  
Syed Hissar ◽  
Noman Anwar ◽  
...  

Abstract Objectives Tuberculosis continues to be a major public health problem globally, despite incredible advancements in healthcare system. In Unani system of medicine, Qurs Tabasheer Sarthani (QTS) and Arq Hara Bhara (AHB) have been traditionally used for tuberculosis like conditions. The study was aimed to investigate the effects of co-administration of QTS and AHB with category I first line antitubercular drugs (CAT-I) on the indices of liver and kidney function in rats. Methods QTS and AHB were prepared individually and mixed to achieve final compound Unani pharmacopoeia formulation (UPF). The human equivalent doses for rats were calculated and administered with and without CAT-I. The effects of the formulations on serum indices of kidney and liver function, hematological markers and plasma CAT-I drug levels were estimated at 14th, 60th & 180th days of treatment. Results The administration of UPF, CAT-I and UPF + CAT-I altered the levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and gamma glutamyltransferase (GGT) and haematological markers. These alterations were within permissible range and randomly distributed among groups during various time points. Administration of CAT-I alone resulted in moderate histopathological changes which were completely abrogated in CAT-I + UPF co-administered animals. The co-administration of UPF with CAT-I improved the plasma peak rifampicin (RIF) levels, without altering the liver and kidney functions. Conclusions The co-administration of UPF with ATT improved liver and kidney functions and increased the plasma levels of RIF. These beneficial findings provide a scope to evaluate the pharmacokinetic studies in humans.



2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Aderemi A. Alabi

Abstract Geophysical and geotechnical techniques were applied to determine the suitability of the sub-surface structure of Akole community area, Abeokuta, Nigeria, for the construction of engineering structures (CES). Four vertical electrical soundings (VES) were carried out, and 10 samples from different points at 1 m depth were analysed to determine soil moisture content, specific gravity (SG), Atterberg limits and California bearing ratio (CBR). The geoelectric sections revealed a maximum of five layers with the typical sounding curves of AKH and HKH types. Sieve analysis and tests for compaction limit, Atterberg limits, SG, optimum moisture content and maximum dry density for compaction limit revealed that samples SP2, SP3, SP4, SP6, SP7, SP8, SP9 and SP10 are of low plasticity with SG values that fall within the permissible range, while SP1 and SP5 are of medium plasticity and their SG values fall below the range of standard specifications. CBR analysis showed that SP1 and SP5 have low load-bearing capacities. VES 1 and 2, linked with SP1 and SP5, are considered unstable and unsuitable to support the CES with shallow foundations; however, excavation of weak layers up to a depth of 5 m and reinforcement will enable the support. Določitev primernosti tal za gradnjo inženirskih objektov na območju skupnosti Akole v Nigeriji je bila izvedena s pomočjo uporabe geofizikalnih in geotehničnih metod. Izvedene so bile štiri navpične sondažne geo-električne meritve. Za določitev vlažnosti, specifične teže, konsistenčnih mej in kalifornijskega indeksa nosilnosti (CBR) je bilo preiskanih deset vzorcev tal iz različnih lokacij globine 1 m. Geo-električni prerezi so pokazali maksimalno pet različnih plasti s tipičnimi sondažnimi krivuljami tipa AKH in MKH. Na vzorcih tal z oznakami SP2, SP3, SP4, SP6, SP7, SP8, SP9 in SP10 so bile opravljene sejalna analiza, določitev meje zgoščevanja, določitev konsistenčnih mej, specifična teža, optimalna vlažnost in maksimalna suha gostota za mejo zgoščevanja. Vzorci imajo nizko stopnjo plastičnosti in specifično težo, ki spada v dovoljeno območje. Vzorca tal z oznakami SP1 in SP5 imata srednjo stopnjo plastičnosti in spadata pod območje standardnih zahtev. Preiskava s testom CBR je pokazala, da imata vzorca tal SP1 in SP5 nizko nosilnost na obtežbo. Preiskavi VES 1 in 2 sta prav tako pokazali, da sta vzorca SP1 in SP5 nestabilna ter neprimerna za temeljenje pri gradnji inženirskih objektov s plitvim temeljenjem, čeprav bi z odstranitvijo plasti globine do 5 m in armiranjem dosegli primerno nosilnost za temeljenje.



Author(s):  
S. Usikov ◽  
T. Starikova

Modern heating systems are a complex set of equipment and elements, the main task of which is to provide comfortable conditions in the serviced premises, regardless of external deflecting factors. Water heating systems with variable hydraulic mode are the most common type of heating in newly constructed residential and public buildings. The installation of differential pressure regulators in individual heating systems is mandatory from the point of view of ensuring noiseless operation and reducing the mutual influence of regulatory areas. However, the location of their installation is controversial in the professional community. This paper covers the range of hydraulic modes of operation of two variants of the design of individual heating system used in this practice of system design: installation of only floor-by-floor collectors, followed by the connection of internal apartment circuits, or with the installation of additional collectors in each apartment. Formulas for estimating changes in the coolant flow rate during operation with high-quality individual control of the system are proposed. The values of the degree of opening of the regulators in the entire permissible range of operation of the system, the hysteresis and the pressure loss created by the differential pressure regulator are obtained. Conclusions are drawn about the rationality of using the proposed designs of the apartment-by-apartment heating system



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