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2021 ◽  
Vol 1 (8) ◽  
pp. 12-17
Author(s):  
I. A. Bikova ◽  
N. I. Zavodchikova

The article considers the problem of the lack of task variety in the existing task bases for preparing schoolchildren for the Basic State Exam in informatics. The need to use tasks in the training process with the similar texts as in the Basic State Exam tasks, but excluding the possibility of applying a template, is substantiated. The authors introduce the concept of a large-scale task, which is a sequence of interconnected tasks. It is proposed to use an approach based on the analysis of the structure of the conditions of the tasks presented in the demo versions of test materials. The large-scale task is based on a variation of conditions and requirements of the tasks for multi-component tasks and for two-component tasks it is based on the selection of a sequence of subtasks. The article describes examples of the process of developing large-scale tasks aimed to prepare for the Basic State Exam in informatics.


Tribologia ◽  
2021 ◽  
Vol 296 (2) ◽  
pp. 29-35
Author(s):  
Magdalena Lemecha ◽  
Krzysztof Ligier ◽  
Jerzy Napiórkowski

This paper presents a study of the tribological wear rate for PTFE-based composites in combination with C45 steel. PTFE composites with the addition of glass fibre, bronze, carbon fibre, and graphite were selected for the study. Tribological tests were conducted in a roller-block combination over an expanded contact area with no lubrication, using an SMC-2 machine. The study assessed the mass and volumetric wear for the test materials and the wear rate index. The highest wear values were noted for the PTFE composite with the addition of bronze, while the lowest was for the PTFE composite with the addition of glass fibre. For all the test materials, the formation of a polymer film on the steel counter specimen was noted.


2021 ◽  
Author(s):  
◽  
Barli Bram

<p>This research investigates the directionality of major total conversion in English, where major total conversion is defined as the process and at the same time as the result of deriving a new lexical item by altering the part of speech of the base without marking the alteration overtly, as in the presumed pair dry – to dry. The question is whether there is a reliable strategy for deciding which member of a pair is the base and which member is the converted counterpart. Various attempts had been made to resolve the controversial directional issue, but the results have been inconsistent. The investigation aims to discover whether or not there exists a coherent notion about how to decide directionality by considering four factors assumed in the literature to reflect directionality. A large corpus of potential examples of major total conversion was collected to act as test materials. The four factors were compared for each major total conversion pair to see to what extent there was agreement among them. Results showed the factors did not agree to the expected extent. The findings are discussed in detail and it is claimed the inconsistencies can often be explained with recourse to a few general principles. In conclusion, on the whole the four factors considered are consistent with one another. In other words, the notion about how to determine directionality in major total conversion is coherent and can be maintained for English.</p>


2021 ◽  
Author(s):  
◽  
Barli Bram

<p>This research investigates the directionality of major total conversion in English, where major total conversion is defined as the process and at the same time as the result of deriving a new lexical item by altering the part of speech of the base without marking the alteration overtly, as in the presumed pair dry – to dry. The question is whether there is a reliable strategy for deciding which member of a pair is the base and which member is the converted counterpart. Various attempts had been made to resolve the controversial directional issue, but the results have been inconsistent. The investigation aims to discover whether or not there exists a coherent notion about how to decide directionality by considering four factors assumed in the literature to reflect directionality. A large corpus of potential examples of major total conversion was collected to act as test materials. The four factors were compared for each major total conversion pair to see to what extent there was agreement among them. Results showed the factors did not agree to the expected extent. The findings are discussed in detail and it is claimed the inconsistencies can often be explained with recourse to a few general principles. In conclusion, on the whole the four factors considered are consistent with one another. In other words, the notion about how to determine directionality in major total conversion is coherent and can be maintained for English.</p>


2021 ◽  
Vol 2107 (1) ◽  
pp. 012057
Author(s):  
Erdy Sulino Mohd Muslim Tan ◽  
Marni Azira Markom ◽  
A.M. Andrew ◽  
MHA Hamid ◽  
Muhammad Aiman Hakim Muhammad Izham ◽  
...  

Abstract Face masks have become a necessary thing that people need to wear daily. Even though some people might already be vaccinated, there is still a chance that the Covid-19 virus could still infect them. Hence, this paper presents a device developed to help determine the quality of face masks crucial in preventing the spread of the virus. These devices can calculate the temperature outside the face mask at a maximum distance of three meters. The way this device works is by measuring the temperature released out of the face mask. Here, the developments of the device with the ability to help determine the quality of face masks are explained and discussed. In the end, the device is perfectly functioning and definitely would assist in verifying the quality of the face masks being worn by someone. Two types of faces are used as test materials: the KN95 type face mask and the 3ply facemask used in Malaysia. Each facemask collected data from 30 minutes to 300 minutes for ten subjects over ten days. Studies that have been conducted show that the thermal value of the KN95 facemask increased to 30.27°C after 5 hours of use. At the same time, the 3ply type facemask offers a thermal value of up to 34.58oC after 5 hours of use. This shows a thermal value difference of up to 4.3PC for both facemasks after 5 hours of use.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Cadie Martin ◽  
Laura Purevdorj-Gage ◽  
Wei Li ◽  
Timothy J. Shary ◽  
Bin Yang ◽  
...  

Control of denture plaque biofilms is a practical approach to preventing persistent oral infections such as denture stomatitis. Objectives. This study compared in vitro biofilm attachment and growth on a new denture material, Ultaire® AKP, with that on traditional denture materials including cobalt chrome (CoCr), polymethyl methacrylate (PMMA), and polyoxymethylene (POM). Methods. Microbial biofilms were grown with cultures of Candida albicans, Streptococcus mutans UA159, or a mixed Streptococcus spp. (S. mutans 700610/Streptococcus sanguinis BAA-1455) for 6 hours in a static protocol or 24 hours in a dynamic protocol for each material. Adherent biofilm cells were removed, and viable colony-forming units (CFUs) were enumerated. Confocal microscopy of the 24-hour Streptococcus spp. biofilms was used to determine biofilm mass and roughness coefficients. Results. The rank order of C. albicans attachment after 6 hours was CoCr > PMMA ∗  > Ultaire® AKP ∗ ( ∗ vs CoCr, p ≤ 0.05 ), and that for 24-hour biofilm growth was CoCr > Ultaire® AKP ∗  > PMMA ∗ ( ∗ vs CoCr, p ≤ 0.05 ). The rank order of S. mutans biofilm attachment was CoCr > POM > Ultaire® AKP ∗  > PMMA ∗ ( ∗ vs CoCr, p ≤ 0.05 ), and that for the 24-hour Streptococcus spp. biofilm growth was POM > Ultaire® AKP > PMMA > CoCr ∗ ( ∗ vs POM, p ≤ 0.05 ). Confocal images revealed structural differences in Streptococcus spp. biofilms on CoCr compared with the other test materials. Significantly lower roughness coefficients of Streptococcus spp. biofilms on Ultaire® AKP were noted, suggesting that these biofilms were less differentiated. Ultaire® AKP promoted significantly less C. albicans and S. mutans biofilm attachment than CoCr at 6 hours and C. albicans growth at 24 hours. Streptococcus spp. biofilms on Ultaire® AKP were less differentiated than those on other test materials. Conclusion. In addition to its material strength, Ultaire® AKP represents an attractive option for denture material in removable partial dentures.


Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2941
Author(s):  
Pei-Wen Peng ◽  
Chiung-Fang Huang ◽  
Ching-Ying Hsu ◽  
Ann Chen ◽  
Ho-Him Ng ◽  
...  

This study evaluated color stability and staining susceptibility of five direct resin-based composites (RBCs) subjected to light-activated in-office bleaching with 40% hydrogen peroxide (HP). The test materials included 5 RBCs, which consisted of one nano-filled, one sub-micron, one bulk-filled, and two nano-hybrid RBC types. Ten disc-shaped specimens of each RBC were fabricated and divided into bleaching (BLE) and non-bleaching (CON) groups (n = 5 for each group). Specimens were then immersed in red wine solution over 4 h. A spectrophotometer was used to obtain Commission Internationale de l’Eclairage (CIE) L*a*b* parameters for each of the following periods tested: before bleaching (TBA), after bleaching (TBL), and after staining (TST). Color stability and staining susceptibility were evaluated using two metrics, CIEDE2000 color differences (ΔE00) and whiteness variations using the whiteness index (ΔWID). Data were analyzed using repeated measures two-way analysis of variance (ANOVA) (α = 0.05). Statistically significant and clinically unaccepted ΔE00 and ΔWID were observed for all tested specimens between TBA and TBL. The nano-hybrid type RBCs showed the highest discoloration among materials after bleaching treatment. The BLE group exhibited significantly higher ΔE00 and ΔWID than the CON group for all the tested RBCs between TBA and TST. The sub-micron type RBC showed the highest discoloration among materials after immersion in the red wine. Conclusion. The light-activated in-office bleaching with 40% HP’s influences on color and whiteness index were material-dependent. The use of bleaching treatment also increased the susceptibility to red wine for all RBCs.


2021 ◽  
Vol 8 (2) ◽  
pp. 56-61
Author(s):  
Divyashree R ◽  
Kirthi Raj

: The present study assessed and compared the success of an IPT procedure both clinically and radiographically when Dycal and MTA were used as an IPT material on primary molars.Children aged 4-9 years were screened and those who fulfilled the inclusion criteria were selected. Accordingly fiftychildren were divided into 2 groups with 25 patient in each group. Cavity preparation was done and the two test materials (Dycal and MTA) were placed at the base in their respective groups and restored with RMGIC. Post-operative radiograph was taken for baseline data. Patients were assessed at Subsequent at 1 and 6 months both clinically and radiographically. Both the test materials had formed a good biological seal, arrested further caries progression and did not cause any adverse pulpal reaction. However the amount of reparative dentin formed was highest in the Dycal group followed by MTA group. Both the experimental materials Dycal and MTA showed reparative dentin formation at the end of 1 and 6 months and also formed a good biological seal and maintained vitality of the pulp which indicates both are good IPT material.


2021 ◽  
Vol 2021 (2) ◽  
pp. 214-227
Author(s):  
Larisa D. Bednarskaya

The article continues the series of publications on the problems of multilevel comprehension of systematics in modern educational processes. This determines the attitude to the Russian language course as a discipline of the meta-subject integrative level, which allows to integrate the acquired competencies with other subjects of the school cycle. On the basis of the assimilation of theoretical material tendency to diagnose the formation of competencies in the functional aspect is more clearly defined, when the basis of the norms of language focuses on language: a functional-communicative aspect backbone relies on a linguistic basis. Test materials for the exam on the Russian language correspond to the functional-communicative filling the content of the Programs of the GEF. Awareness of the systematic nature of the processes of studying the subject and diagnosing its assimilation allows to intensify both its assimilation and the diagnosis of the formed competencies, opens up prospects for optimizing the educational process. The article offers examples of compression of theoretical material of different volumes, which help to generalize a huge layer of speech implementations and easily learn them.


2021 ◽  
Vol 887 ◽  
pp. 351-357
Author(s):  
Vladimir N. Malikov ◽  
Alexey V. Ishkov

This research aims to study boron-based coatings on the surface of steel parts. The significance of this topic is determined by practical considerations of the need to improve strength of the steel surface subjected to high loads. In the course of study, samples of strengthening coatings made of 65G steel obtained by HFEC heating method were created. Then, the samples were subjected to a series of studies using a metallographic microscope, as well as a measuring system based on eddy current effects. The obtained data analysis allows us to conclude about the pattern of electrical conductivity distribution on the surface of test materials with different coatings depending on the quantitative composition of flux when creating boron-based strengthening coatings.


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