scholarly journals TiO2: A Semiconductor Photocatalyst

2021 ◽  
Author(s):  
Azrina Abd Aziz ◽  
Fatema Khatun ◽  
Minhaj Uddin Monir ◽  
Sim Lan Ching ◽  
Leong Kah Hon

Titanium dioxide (TiO2) is considered as an inert and safe material and has been used in many applications for decades. TiO2 have been widely studied, due to its interesting general properties in a wide range of fields including catalysis, antibacterial agents, in civil as nano-paint (self-cleaning) and especially photocatalysis, and that affect the quality of life. Thus, the development of nanotechnologies TiO2 nanoparticles, with numerous novel and useful properties, are increasingly manufactured and used. TiO2 doped with noble metal are good candidates in the performance these applications. The fascinating physical and chemical features of TiO2 depend on the crystal phase, size and shape of particles. For example, varying phases of crystalline TiO2 have different band gaps that rutile TiO2 of 3.0 eV and anatase TiO2 of 3.2 eV, determine the photocatalytic performance of TiO2. This chapter explains basic information on TiO2 and theoretical concepts of nanostructure of TiO2 nanoparticles as a semiconductor photocatalyst.

Author(s):  
George Okeke ◽  
Robert B. Hammond ◽  
S. Joseph Antony

Nanoparticles are nanometer sized metallic oxides which possess enhanced properties that are desirable to a wide range of industries. In this study, we investigate structural and surface properties of anatase TiO2 nanoparticles in vacuum and water environments using molecular dynamics simulations. The particle sizes ranged from 2 to 6 nm and simulations were performed at 300 K. Surface energy of the particles in vacuum was seen to be higher than that of the particles in water by about 100% for the smaller particles (i.e. 2 and 3nm) and about 60% for the larger particles (i.e. 4 to 6 nm). Surface energy of the particles in both environments, is seen to increase to a maximum (optimum value) as the particle size increases after which no further significant increase is observed. In vacuum, studies carried out at temperatures ranging from 300–2500 K showed a high dependence of surface energy on temperature. The estimated surface tension of water is seen to agree quite well with that of experiments.


Author(s):  
Д.А. Китова ◽  
А.А. Китов

Понятие «менталитет» становится предметом широкого научного дискурса и тяготеет и в отечественной, и в зарубежной литературе к междисциплинарному пониманию. Это сопряжено с широким составом понятий, которые входят в его структуру, и прикладными особенностями его развития - историчностью, устойчивостью/изменчивостью, идеологической лояльностью культур и т.д. Дальнейшая его разработка требует выработки схем описания его структурной композиции, уточнения базовых теоретических концепций, операциональных схем эмпирического анализа и структурирования различных его видов. Проблемы изучения экономического менталитета связаны с содержанием базового понятия и его спецификой - он представляется структурным компонентом российской полиментальности и требует психологического анализа различных его аспектов: сущности и характера его влияния на экономическое поведение личности, корпоративное взаимодействие и экономическое развитие страны в целом. Изучения требуют взаимное проникновение психологических и экономических факторов, прогнозирование их влияния на экономические показатели государства, выделение его функциональных характеристик, а также интенсивность и выраженность психологических свойств и условий культурного развития различных обществ. Выявлен ряд связанных с ним феноменов: взаимовлияния качества жизни и чувства экзистенциальной безопасности; влияния общественного сознания на темпы роста экономики; взаимозависимости качества жизни и субъективной удовлетворенности жизнью; различий в представлениях о причинах бедности преимущественно обеспеченных и нуждающихся слоев населения. Показано, что системно-структурный анализ информационных процессов в интернете (анализ запросов в Google) отражают психологические закономерности возникновения и развития интереса к экономическим явлениям. Предлагаемые подходы позволяют обоснованно считать, что возможно выявление новых знаний об экономическом менталитете. The concept of «mentality» is becoming the subject of a broad scientific discourse and tends, both in domestic and foreign literature, to interdisciplinary integration in the study of the psychology of peoples. It was revealed that the broad interpretation of mentality is associated with a wide range of categories that are included in its structure, and applied features of development - historicity, variability, ideological loyalty of cultures, etc. It seems that further development of the concept requires the development of schemes for describing the structural composition of the mentality, clarification of basic theoretical concepts, operational schemes of empirical analysis and structuring of its various types. The paper describes the problems of studying the economic mentality, which naturally has both problems associated with the study of the basic concept itself, and its own specificity. The economic mentality appears to be a structural component of Russian polymentality and requires an in-depth psychological study of its various aspects: the essence, the nature of the impact on the economic behavior of the individual, corporate interaction and the country's economic development. It was shown that the study requires the mutual penetration of psychological and economic factors, predicting their impact on economic results, highlighting its functional characteristics, identifying the intensity and severity of specific psychological characteristics and conditions of cultural development of societies. It was presented that within the framework of various theoretical approaches and studies, many facts were revealed: the mutual influence of the quality of life and the feeling of existential security; the influence of public consciousness on the rate of economic growth; codependency of the quality of life and subjective life satisfaction; found differences in the perceptions of the wealthy and needy strata of the population about the causes of poverty. It was shown that the systemic and structural analysis of information processes in Google, in particular, the analysis of queries, will make it possible to clearly see that in economies of various types there are certain psychological patterns of interest in economic phenomena that have yet to be substantiated. The proposed approaches make it possible to hope for the identification of new knowledge in the study of economic mentality.


2020 ◽  
Vol 65 (6) ◽  
pp. 375-381
Author(s):  
N. M. Kargaltseva ◽  
V. I. Kocherovets ◽  
A. Yu. Mironov ◽  
O. Yu. Borisova

When diagnosing bloodstream infection (BI) the culture medium is the basis for growth of microorganisms and obtaining the blood culture. Pancreatic digest from fish meal is the basis of all culture media in Russia. In European countries brain-heart media (BHM) are used for detecting microorganisms in blood. In Russia BHM is not produced. The aim is to work out the formulation and the way of the BHM (broth and agar) preparation in order to improve the efficiency of obtaining blood culture. There were defined the physical and chemical indices and biological parameters of the BHM. The microbiological control of the BHM was carried out by diagnostic study of cardiological patients’ blood. On the basis of the developed technique of the brain-heart extraction (BHE) preparation there was created the liquid and agar BHM (LBHM, BHA). The LBHM was poured into bottles which then were filled with the inert gas. The bottles were closed with rubber stoppers and rolled in metal caps became a closed system. Microbiological qualities of LBHM were tested on 260 blood samples and thioglycollate medium (TGM) and LBHM. Aerobic microorganisms grew in LBHM 2,4 times more often than in TGM. The microaerophilic microbes grew in LBHM 3,2 times more often than in TGM. Anaerobic microbes did not show any growth in TGM, (p<0,001). Monomicrobes hemocultures were obtained in LBHM 13,4 times more often than in glucose broth and 2,3 times more often than in TGM, (p<0,001). Polymicrobes hemocultures were obtained in LBHM more often than in TGM (7,3% and 1,7%, respectively). The quality of brain-heart agar (BHA) was tested on 300 blood samples in 5% blood meat-pepton agar (MPA) and BHA in aerobic and anaerobic conditions for both the media. Aerobic microorganisms grew in BHA 2 times more often than in MPA. The microaerophilic microbes grew in BHA 3,6 times more often than in MPA. In anaerobic condition in BHA aerobic microorganisms grew 2 times more often than in MPA and the microaerophilic microbes grew 2,5 times more often than in MPA, (p<0,001). Anaerobic microbes did not grow in MPA. When diagnosing bloodstream infection the BHM (liquid and agar) are able to create the optimal conditions for the increase of the wide range pathogen growth.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
I. Tsykhanovska ◽  
V. Yevlash ◽  
R. Trishch ◽  
T. Lazarieva ◽  
A. Alexandrov

Expansion and improvement of production of jelly and marmalade products requires the search for simplified resource- and energy-saving technology, increasing the stability of a colloidals dispersed system and improving the quality of finished products. Promising technological applications have food additives in the nanometer range, due to unique physical and chemical parameters and a wide range of functional and technological properties. The paper proposes a solution to the problem of stabilizing the colloidal structure of jelly marmalade products and the formation of their quality by using a food additive "Magnetofood" (based on oxides of divalent and trivalent iron: FeO·Fe2O3). "Magnetofood" – ultrafine powder with a particle size of ~80 nm, which has a high functional and technological potential: large specific surface area, surface-active, complexing, sorption, stabilizing properties. This allows us to recommend "Magnetofood" as a food additive of complex action to improve the quality and extend the shelf life of jelly marmalade products, in particular molded jelly marmalade. It is established that the addition of food additive "Magnetofood" in the form of an aqueous suspension at the stage of "swelling-dissolution" of the gelling agent improves the shape, surface and consistency; increases the moisture content by 1,15–1,16 times in agar samples and 1,13–1,14 times in pectin samples; reduces the total acidity by 1,05–1,08 times in agar samples and 1,06–1,09 times in pectin samples; inhibits microbial contamination of the surface of marmalade samples. In addition, the rational content of food additive "Magnetofood" – 0,15% by weight of the prescription mixture and the optimal conditions of temperature and humidity during storage of molded jelly marmalade for 90 days: relative humidity φ=(75±2)%, temperature (18±2)oC.


2020 ◽  
Vol 50 (1) ◽  
Author(s):  
Antonio Carlos Prestes Pereira ◽  
Priscila Judacewski ◽  
Gabriel Coelho ◽  
Renata Dinnies Santos Salem ◽  
Marina Tolentino Marinho ◽  
...  

ABSTRACT: There are no specific technical regulations regarding the identity and quality of white mold surface-ripened cheeses in Brazil. These cheeses are sold both whole (Camembert-type) and in wedges (Brie-type). The aim of the study was to evaluate the physical and chemical properties; technological parameters and microbiological safety of 20 whole cheeses (Camembert-type) and 16 cheese wedges (Brie-type) produced in Brazil. Samples showed a wide range in sodium (91.0-731.0 mg/100 g, cheeses wedges) and calcium (238.0-1100.0 mg/100g, whole cheeses) contents. The cheese groups presented no significant differences in relation to the majority of the analyzed parameters. Listeria monocytogenes was reported in 5% of the whole cheese samples. The other microbiological parameters were in accordance with the current legislation, RDC no 12/2001 of Anvisa. The comparative assessments between these two cheeses indicated that they are different. In addition, the wide range of results indicated a lack of processing standardization. The mean values of the physicochemical and textural parameters should be considered as recommended for these cheeses in Brazil.


2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.


2019 ◽  
pp. 462-471
Author(s):  
Lyudmila Shirokova

The historical polyethnicity of the Slovak society and the connected problems of the interrelations of cultures, ethics, interpersonal relations, are reflected in the works of modern Slovak prose. They are represented most clearly in the novels of middle generation writers P. Rankov, S. Lavrík, P. Krištúfek. They dwell upon the dramatical events of the 20 th century. They cover wide range problems, from the fruitful coexistence of various ethnic groups and their representatives to national contradictions and racial repressions. The artistic quality of the mentioned works, their composition, the way of narrating, the type of the main character, can be highly evaluated. For example, in a novel by P. Rankov the plot, in spite of its linearity, is a chain of episodes in the span of 30 years from the life of the main characters. It reflects not only their fates, but also the historical and political changes of the world they live in. The main female character of a S. Lavrík ’s novel narrates about everyday life and tragedies in the lives of the dwellers of a Slovak town in the Slovak Republic during the war. P. Krištúfek in his novel focuses on several decades from the life of a Slovak-Jewish family and dwellers of a Slovak provincial society with types and relations specific for this milieu.


Author(s):  
Katherine V. Whittington

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.


2020 ◽  
Vol 1 (10(79)) ◽  
pp. 12-18
Author(s):  
G. Bubyreva

The existing legislation determines the education as "an integral and focused process of teaching and upbringing, which represents a socially important value and shall be implemented so as to meet the interests of the individual, the family, the society and the state". However, even in this part, the meaning of the notion ‘socially significant benefit is not specified and allows for a wide range of interpretation [2]. Yet the more inconcrete is the answer to the question – "who and how should determine the interests of the individual, the family and even the state?" The national doctrine of education in the Russian Federation, which determined the goals of teaching and upbringing, the ways to attain them by means of the state policy regulating the field of education, the target achievements of the development of the educational system for the period up to 2025, approved by the Decree of the Government of the Russian Federation of October 4, 2000 #751, was abrogated by the Decree of the Government of the Russian Federation of March 29, 2014 #245 [7]. The new doctrine has not been developed so far. The RAE Academician A.B. Khutorsky believes that the absence of the national doctrine of education presents a threat to national security and a violation of the right of citizens to quality education. Accordingly, the teacher has to solve the problem of achieving the harmony of interests of the individual, the family, the society and the government on their own, which, however, judging by the officially published results, is the task that exceeds the abilities of the participants of the educational process.  The particular concern about the results of the patriotic upbringing served as a basis for the legislative initiative of the RF President V. V. Putin, who introduced the project of an amendment to the Law of RF "About Education of the Russian Federation" to the State Duma in 2020, regarding the quality of patriotic upbringing [3]. Patriotism, considered by the President of RF V. V. Putin as the only possible idea to unite the nation is "THE FEELING OF LOVE OF THE MOTHERLAND" and the readiness for every sacrifice and heroic deed for the sake of the interests of your Motherland. However, the practicing educators experience shortfalls in efficient methodologies of patriotic upbringing, which should let them bring up citizens, loving their Motherland more than themselves. The article is dedicated to solution to this problem based on the Value-sense paradigm of upbringing educational dynasty of the Kurbatovs [15].


2019 ◽  
Vol 65 (1) ◽  
pp. 16-26
Author(s):  
Pavel Rumyantsev ◽  
Petr Nikiforovich ◽  
Andrey Poloznikov ◽  
Andrey Abrosimov ◽  
Vladimir Saenko ◽  
...  

Mutation BRAFV600E is highly specific for papillary thyroid carcinoma. It’s detected in 40-70% of all papillary thyroid carcinoma cases. Moreover this mutation is noticed in anaplastic carcinoma in 40-50%.This fact gives a chance to select patients and provide targeted therapy with multi-kinase inhibitors in cases of unresectable anaplastic carcinoma. The influence of BRAF V600E mutation for response to radioactive iodine therapy requires more evidence-based research. Existing methods for determining the BRAFV600E mutation have different accuracy, availability and cost. Other methodological aspects are also associated with the sample preparation of biological material, the quality of reagents, and the cross-validation of research results. In this review, on the basis of our own experience and literature data, the indications for determining the mutation of the BRAFV600E gene in clinical practice are refined, and a comprehensive comparative analysis of modern research methods has been conducted. This review is focused on a wide range of specialists of different types: oncologists, endocrinologists, radiologists, pathologists, and biologists.


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