composition properties
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Author(s):  
Yangpeng Zhuo ◽  
Chen Zhang ◽  
Yanfang Zhao ◽  
Benxiang Hu ◽  
Shuangquan Liao ◽  
...  

Folia Medica ◽  
2021 ◽  
Vol 63 (6) ◽  
pp. 901-904
Author(s):  
Kostadin Zhekov ◽  
Vesela P. Stefanova

Introduction: The term “bioceramic” is used in endodontics to describe various products and is often used in general terms for mineral trioxide aggregate (MTA) and other hydroscopic dental cements (HDC), which creates confusion in the terminology. Aim: The aim of the study is to present a definition and an original classification of bioceramic endodontic sealers. Materials and methods: A total of 123 articles were found by the PubMed search engine using the key phrase “bioceramic endodontic sealers”. Of these 123 articles, we analyzed 20 articles that contain information about the composition, properties, definition, and classification of bioceramic endodontic sealers. Results: In accordance with the collected data on the composition and the delivery form of calcium silicate endodontic sealers, we propose a new definition of bioceramic endodontic sealers that clarifies the specificities of these materials. In the new classification they are divided by two criteria: source of calcium silicate and form of delivery. It also contains the particular products’ names in order to aid their usage in the clinical practice.  Conclusions: The new definition of bioceramic endodontic sealers clears out the confusion in the terminology, which promotes the classification of these products and helps understanding their clinical application.


2021 ◽  
Author(s):  
Andrey Serebryakov ◽  
Tat'yana Smirnova ◽  
Valentina Mercheva ◽  
Elena Soboleva

This textbook is a publication of the latest generation, designed to optimize the national project "Education"; develops theoretical knowledge about the genesis of natural liquid, gaseous and solid combustible minerals, the formation of the composition and properties, the practical significance of fuel and energy natural complexes. It is devoted to the study of the composition, properties and classification of oils, gas condensate, natural gases and solid combustible minerals, studied at the level of modern achievements of instrumental analytical and factory equipment in accordance with existing technologies, theories and hypotheses about the genesis of hydrocarbons and Earth sciences. The publication is supplemented with the main directions of processing of combustible minerals. Digital and graphical types of chemical models of the synergy of components of gas and oil deposits are described, which are necessary for predicting the phase state and composition of hydrocarbons and optimizing the directions of processing of marketable products. To facilitate the process of cognition of the origin and formation of the composition and properties of natural combustible minerals, a glossary, tests, as well as questions for the test and exam are offered. To control the knowledge gained by students while studying textbook materials, each chapter is accompanied by questions and tasks. Meets the requirements of the federal state educational standards of higher education of the latest generation. It is intended for students studying in the fields of 05.04.01, 05.03.01 "Geology", 21.05.02 "Applied Geology", as well as for specialists in the field of geology, geochemistry, extraction and processing of oil, gas, gas condensate, solid fuels.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3974
Author(s):  
Andrey Vyacheslavovich Vasilyev ◽  
Valeriya Sergeevna Kuznetsova ◽  
Tatyana Borisovna Bukharova ◽  
Egor Olegovich Osidak ◽  
Timofei Evgenevich Grigoriev ◽  
...  

In dentistry, maxillofacial surgery, traumatology, and orthopedics, there is a need to use osteoplastic materials that have not only osteoinductive and osteoconductive properties but are also convenient for use. In the study, compositions based on collagen hydrogel were developed. Polylactide granules (PLA) or a traditional bone graft, a mixture of hydroxyapatite and β-tricalcium phosphate (HAP/β-TCP), were used for gel filling to improve mechanical osteoconductive properties of compositions. The mechanical tests showed that collagen hydrogels filled with 12 wt% highly porous PLA granules (elastic modulus 373 ± 55 kPa) or 35 wt% HAP/β-TCP granules (elastic modulus 451 ± 32 kPa) had optimal manipulative properties. All composite components were cytocompatible. The cell’s viability was above 90%, and the components’ structure facilitated the cell’s surface adhesion. The bone morphogenetic protein-2 (BMP-2) provided osteoinductive composition properties. It was impregnated directly into the collagen hydrogel with the addition of fibronectin or inside porous PLA granules. The implantation of a collagen hydrogel with BMP-2 and PLA granules into a critical-size calvarial defect in rats led to the formation of the most significant volume of bone tissue: 61 ± 15%. It was almost 2.5 times more than in the groups where a collagen-fibronectin hydrogel with a mixture of HAP/β-TCP (25 ± 7%) or a fibronectin-free composition with porous PLA granules impregnated with BMP-2 (23 ± 8%) were used. Subcutaneous implantation of the compositions also showed their high biocompatibility and osteogenic potential in the absence of a bone environment. Thus, the collagen-fibronectin hydrogel with BMP-2 and PLA granules has optimal biocompatibility, osteogenic, and manipulative properties.


Author(s):  
Andrey Vasilyev ◽  
Valeriya Kuznetsova ◽  
Tatyana Bukharova ◽  
Egor Osidak ◽  
Timofei Grigoriev ◽  
...  

In dentistry, maxillofacial surgery, traumatology, and orthopedics, there is a need to use osteoplastic materials that have not only osteoinductive and osteoconductive properties but are also convenient for use. In the study, compositions based on collagen hydrogel were developed. Polylactide granules (PLA) or a traditional bone graft, a mixture of hydroxyapatite and β-tricalcium phosphate (HAP/β-TCP), were used for gel filling to improve mechanical osteoconductive properties of compositions. The mechanical tests showed that collagen hydrogels filled with 12 wt% highly porous PLA granules (elastic modulus 373 ± 55 kPa) or 35 wt% HAP/β-TCP granules (elastic modulus 451 ± 32 kPa) had optimal manipulative properties. All composite components were cytocompatible. The cell’s viability was above 90%, and the components’ structure facilitated the cell’s surface adhesion. The bone morphogenetic protein-2 (BMP-2) provided osteoinductive composition properties. It was impregnated directly into the collagen hydrogel with the addition of fibronectin or inside porous PLA granules. The implantation of a collagen hydrogel with BMP-2 and PLA granules into a critical-size calvarial defect in rats led to the formation of the most significant volume of bone tissue: 61 ± 15%. It was almost 2.5 times more than in the groups where a collagen-fibronectin hydrogel with a mixture of HAP/β-TCP (25 ± 7%) or a fibronectin-free composition with porous PLA granules impregnated with BMP-2 (23 ± 8%) were used. Subcutaneous implantation of the compositions also showed their high biocompatibility and osteogenic potential in the absence of a bone environment. Thus, the collagen-fibronectin hydrogel with BMP-2 and PLA granules has optimal biocompatibility, osteogenic, and manipulative properties.


2021 ◽  
Author(s):  
Alexandra Győrfi ◽  
Csaba Leitol

Abstract In the sorting plant examined during the research, the sorting of the selectively collected mixed packaging waste is done by hand. Studies were performed on the quantitative changes of the waste stream entering and leaving the sorting plant, the composition properties according to the particle size, and lastly the number of pickings. The amount of incoming waste has increased linearly over the years. The sizes preferred by the optical separators were the guideline during the measurements. Sixty percentage of all incoming waste falls in the ideal range of 70–350 mm, 20% in the range of <70 mm and 20% in the range of >350 mm. Because there are significant differences in composition and quantities as the seasons and months alternate, these results provide important information for engineers designing a mechanized technology.


Author(s):  
Л.В. АНТИПОВА ◽  
Н.С. РОДИОНОВА ◽  
Е.С. ПОПОВ

Рассмотрены основные требования к науке о питании и новые подходы к усовершенствованию состава, свойств и технологий пищевых продуктов, обусловленные изменением пищевого статуса человека, к которому предъявляются более высокие критерии, учитывающие изменения экологии, условий и интенсивности труда, влияние стрессов на психоэмоциональное состояние человека. Установлено, что основные направления совершенствования биопотенциала и гигиенического статуса пищевых продуктов на этапе проектирования рецептурных решений базируются на привлечении новых нутрицевтиков, парафармацевтиков, эубиотиков из сырья природного происхождения или продуктов его глубокой переработки. Перспективным направлением в совершенствовании технологий и расширении ассортимента продуктов функционального назначения, направленного диетического, лечебного и профилактического действия, необходимых для организации биокорректирующего питания и ликвидации алиментарно-дефицитных состояний различных групп населения, является применение нейросетевых методов математического моделирования, которые позволят с высокой точностью получать значения выходных показателей качества пищевых систем в зависимости от варьирования исходных характеристик и параметров технологических процессов. The basic requirements for nutritional science and new approaches to improve the composition, properties and technologies of food products due to changes in the nutritional status of the person to which higher demands are placed, taking into account environmental changes, conditions and intensity of labour, the impact of stress on mental and emotional state, are considered. It is established that the main directions of improvement of the biopotential and the hygienic status of food products at the design stage prescription decisions are based on the attraction of new nutraceuticals and parapharmaceutics, eubiotikov from raw materials of natural origin or products of its deep processing. A promising direction in improving the technology and expanding the range of functional foods aimed diet, therapeutic and preventive actions needed for the organization of bio correction power and to eliminate the nutritional-deficient states of various groups population groups, is the application of neural network mathematical modeling methods, which allow with high accuracy to obtain values of output indicators of the quality of food systems, depending on the variation of initial characteristics and parameters of technological processes.


2021 ◽  
Vol 57 (6) ◽  
pp. 721-721
Author(s):  
I. V. Paladii ◽  
E. G. Vrabie ◽  
K. G. Sprinchan ◽  
M. K. Bologa

Author(s):  
S. V. Knyazev ◽  
N. A. Kozyrev ◽  
A. A. Usol’tsev ◽  
A. R. Mikhno

The formation of foundry and technological defects in castings is largely influenced by the quality of casting molds, which in most cases is determined by the composition and properties of the molding mixture. To ensure optimal parameters of the molding mixture, automation and optimization of control of technological processes of mixture preparation, algorithms for the functioning of process control systems have been developed. The description of the circuit and methods of control using process control system presented. It was shown that the algorithms provide the calculation of the generalized optimization parameter according to the values of the main physical, mechanical and technological properties of the components of the molding mixture, sequential analysis and search of the optimum by the simplex method of Nelder–Mead with restrictions on several parameters. Subsystems of the process control systems considered, which enable to change quickly the technology according to the criterion of minimum defectiveness. The algorithm for calculating the values of the generalized criterion of the quality of the mixture includes a mathematical model “composition – properties” of the mixture, linking the content of the component of the molding mixture (spent mixture, quartz sand, lignosulfonate, bentonite suspension, water) with the values of physical, mechanical and technological properties (compressive strength in the wet state, rammability, formability, gas permeability, binder content, fluidity, wetness and crumbling). The current values of the quality parameters of the mixture are determined as a result of express analysis in the shop laboratory and by automatic sensors. The proposed algorithm of optimization control of preparation of the molding mixture enables to develop recommendations of technological and organizational nature and to set recipes of the molding mixture that minimize the level of defectiveness of castings. An adapted version of the algorithm has been tested for use in the preparation of various brands of molding and rod mixtures, which indicates its versatility.


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