ChemInform Abstract: PHEROMONE SYNTHESIS. XLVI. SYNTHESIS OF THREE STEREOISOMERIC FORMS OF 2,8-DIMETHYL-1,7-DIOXASPIRO(5.5)UNDECANE, THE MAIN COMPONENT OF THE CEPHALIC SECRETION OF ANDRENA WILKELLA

1982 ◽  
Vol 13 (1) ◽  
Author(s):  
K. MORI ◽  
K. TANIDA
Keyword(s):  
Main Component ◽  
Cephalic Secretion

Total etch dentin bonding systems: scanning electron microscopy of the resin-dentin hybrid layer

1992 ◽  
Vol 50 (2) ◽  
pp. 1092-1093
Author(s):  
Jorge Perdigao
Keyword(s):  
Composite Resin ◽  
Mechanical Interlocking ◽  
Hybrid Layer ◽  
Agent Based ◽  
Dentin Bonding ◽  
Acid Agent ◽  
Bond Strengths ◽  
Main Component ◽  
Bonding Systems ◽  
New Generation

In 1955, Buonocore introduced the etching of enamel with phosphoric acid. Bonding to enamel was created by mechanical interlocking of resin tags with enamel prisms. Enamel is an inert tissue whose main component is hydroxyapatite (98% by weight). Conversely, dentin is a wet living tissue crossed by tubules containing cellular extensions of the dental pulp. Dentin consists of 18% of organic material, primarily collagen. Several generations of dentin bonding systems (DBS) have been studied in the last 20 years. The dentin bond strengths associated with these DBS have been constantly lower than the enamel bond strengths. Recently, a new generation of DBS has been described. They are applied in three steps: an acid agent on enamel and dentin (total etch technique), two mixed primers and a bonding agent based on a methacrylate resin. They are supposed to bond composite resin to wet dentin through dentin organic component, forming a peculiar blended structure that is part tooth and part resin: the hybrid layer.

Study regarding the health coefficients for the citizens who practice free time sport activities for the increase of life quality

2014 ◽  
Vol 6 (12) ◽  
pp. 7-12 ◽  
Author(s):  
Liliana Dacica
Keyword(s):  
Motor Skills ◽  
Social Relations ◽  
Life Quality ◽  
Free Time ◽  
Health State ◽  
Beneficial Effects ◽  
Sports Programs ◽  
Sport Activities ◽  
Main Component ◽  
Sports Activities

Abstract The paper presents the results of a determinative study regarding the health profits obtained by the citizens of Caras-Severin County involved in the practice of leisure sport through the program sport for all offered. The aspect highlighted is that sport, for all, has beneficial effects on health being contained by all the components of life quality. The aim of the paper is to prove that issuing leisure time sports programs according to the needs of the client population increases the number of practitioners of sport and implicitly it contributes to the maintenance and improvement of the health state. In order to pursue health profits, the physical and psychic wellbeing of the participants in the sports programs, the observation method, the tests method and the method of recording the health coefficients on a protocol basis were used. The observation was achieved on a sample of 217 subjects which were initially tested, at the beginning of the programs and at the end of the research period. The conclusion was that the main component elements of life quality which can be ameliorated by free time sport activities are: health state; the biologic potential through the evaluation of the anthropometric, functional and physiological coefficients; motor skills; psycho-social relations and social integration. The health state, the biologic potential, motor skills, socialization can be considered dependent variables and through sports activities for all and through the implemented programs a strategic project of continuous development can be elaborated. Leisure sports activities ameliorate life quality of different categories of citizens and social groups.

Solving the Problem of Silicon Dioxide Melting Based on Deviation Model

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Yuhan Sun
Keyword(s):  
Silicon Dioxide ◽  
Blast Furnace Slag ◽  
Melting Process ◽  
Melting Rate ◽  
Dissolution Behavior ◽  
Characteristic Parameters ◽  
Contour Feature ◽  
Time Periods ◽  
Main Component ◽  
Furnace Slag

Abstract: In order to reveal the dissolution behavior of iron tailings in blast furnace slag, we studied the main component of silica in iron tailings. First, edge contour features need to be established to represent the melting process of silica. We choose shape, perimeter, area and generalized radius as objects. By independently analyzing the influence of these four indexes on the melting rate, the area and shape were selected as the characteristic parameters of the edge contour of the silica particles. Then, the actual melting rate of the silica is estimated by the edge contour feature index. Finally, we can calculate the melting rate of the first second of three time periods of 0.00010312mm3/s，0.0002399mm3/s，0.0000538mm3/s.

THYMUS VARIABILITY IN WHITE RATS EXPOSED TO FORMALDEHYDE

2019 ◽  
pp. 105-116
Author(s):  
V.N. Voloshin ◽  
I.S. Voloshina ◽  
I.Yu. Vash
Keyword(s):  
White Male ◽  
Principal Component ◽  
Middle Part ◽  
Procrustes Analysis ◽  
Male Rats ◽  
Canonical Variables ◽  
Generalized Procrustes Analysis ◽  
White Rats ◽  
Main Component ◽  
Formaldehyde Inhalation

The aim of the paper is to study thymus variability in white rats, which were exposed to formaldehyde, and to compare these data with the indicators in control animals. Materials and Methods. The trial enrolled 72 white male rats, initial body weight 40–50 g. The animals were divided into 2 groups (36 rats in each). The first group consisted of control rats. Animals of the second group were exposed to formaldehyde inhalation, 2.766 mg/m3. To characterize the variability of the organ size, centroids were determined. The superposition of landmark configurations was performed using the generalized Procrustes analysis method, MorphoJ 1.06d program. The principal component analysis and canonical analysis of the obtained data were carried out. Results. One-Way ANOVA revealed a high level of intergroup differences in Procrust distance (F=1.34; p<0.0001). The significant effect of the duration of formaldehyde exposure on centroid size was established. The Kruskal-Wallis criterion was 19.778 (p=0.0014). The analysis of the principal components indicated that each of the first 10 components stands for more than 1 % of Procrustes coordinate variance. In this case, the first 7 components compatibly explain 91.398 % of thymus variability. The proportion of the first main component to the total variance of the Procrustes coordinates is 40.236 %. PC1 (-) shows changes in the thymus shape, mostly affecting the tops of its lobes, the middle part of the right boundary and the entire left thymus boundary. The scattering ellipses of the thymus ordinates in rats exposed to formaldehyde, in the first two canonical variables are located higher than those in the control animals. Conclusion. Formaldehyde inhalation leads to thymus changes in white rat. The most significant differences with control data are determined along the second canonical variable. Keywords: thymus, form, rat, formaldehyde, geometric morphometry. Цель. Изучение изменчивости формы тимуса белых крыс, находившихся в условиях влияния формальдегида, и сравнение этих данных с показателями, полученными у контрольных животных. Материалы и методы. Работа выполнена на 72 белых крысах-самцах с начальной массой тела 40–50 г. Животные были разделены на 2 серии (по 36 крыс). Первую серию составляли контрольные крысы. Животные второй серии подвергались ингаляционному воздействию формальдегида (ФА) в концентрации 2,766 мг/м3. Для характеристики изменчивости размеров органов определяли размер их центроидов. Процедуру суперимпозиции конфигураций ландмарок выполняли методом генерализованного прокрустова анализа с использованием программы MorphoJ 1.06d. Проводили анализ главных компонент и канонический анализ полученных данных. Результаты. Однофакторный дисперсионный анализ выявил высокий уровень межгрупповых различий по показателю прокрустовых расстояний (F=1,34; р<0,0001). Установлено значительное влияние продолжительности нахождения животных в условиях воздействия ФА на размер центроида. Критерий Краскела–Уоллиса составил 19,778 (р=0,0014). Анализ главных компонент указывал на то, что каждая из первых 10 компонент объясняет более 1 % дисперсии прокрустовых координат. При этом первые 7 компонент совместно объясняют 91,398 % изменчивости формы тимуса. Вклад первой главной компоненты в общую дисперсию прокрустовых координат составляет 40,236 %. РС1 (–) показывает изменения формы тимуса, в большей степени затрагивающие верхушки его долей, среднюю часть правого контура и весь левый контур тимуса. Эллипсы рассеивания ординат тимусов, принадлежащих крысам, подвергавшимся влиянию ФА, в пространстве первых двух канонических переменных расположены выше по отношению к таковым контрольных животных. Заключение. Ингаляционное воздействие формальдегида приводит к изменению формы тимуса белых крыс. Наибольшие различия с контрольными данными определяются вдоль второй канонической переменной. Ключевые слова: тимус, форма, крыса, формальдегид, геометрическая морфометрия.

Justification of design parameters of the fractional reaping conveyor and its devices for removal of beveled stems from under the wheels of the vehicle

2019 ◽  
Vol 1 (3) ◽  
pp. 1-10
Author(s):  
Mikhail M. Konstantinov ◽  
Ivan N. Glushkov ◽  
Sergey S. Pashinin ◽  
Igor I. Ognev ◽  
Tatyana V. Bedych
Keyword(s):  
Optimal Design ◽  
Technological Process ◽  
Design Parameters ◽  
Theoretical Studies ◽  
Optimal Parameters ◽  
Belt Conveyor ◽  
Grain Crops ◽  
Mode Of Operation ◽  
Optimal Values ◽  
Main Component

In this paper we consider the structural and technological process of the combine used in the process of separate harvesting of grain crops, as well as a number of its parameters. Among the main units of the combine, we allocate a conveyor and devices for removing beveled stems from under the wheels of the vehicle. The principle of operation of the conveyor at different phases of the Reaper and especially the removal of cut stems from under the wheels of the vehicle during operation of the Reaper. The results of theoretical studies on the establishment of the optimal design of the parameters of the belt conveyor are presented, the ranges of their optimal values are considered and determined. Studies on the establishment of optimal parameters of the screw divider in the Reaper, which is the main component of the device for removal of beveled stems, are presented. Taking into account the optimal design and mode of operation of the screw divider, the correct work is provided to remove the cut stems from under the wheels of the harvester.

OIL CONTENT AND CHEMICAL COMPOSITION IN THE PARTS OF OIL PALM FRUIT FROM 8 IOPRI VARIETIES

2018 ◽  
Vol 24 (2) ◽  
pp. 67-76
Author(s):  
Sujadi Sujadi ◽  
Hasrul Abdi Hasibuan ◽  
Meta Rivani ◽  
Abdul Razak Purba
Keyword(s):  
Fatty Acid ◽  
Palmitic Acid ◽  
Oil Palm ◽  
Oil Content ◽  
Mean Value ◽  
Oleic Acid Content ◽  
Palm Fruit ◽  
Fruit Samples ◽  
Main Components ◽  
Main Component

Fresh fruit bunches (FFB) consist of fruit be composed grade in few spikelet. Fruit at a spikelet can be distinguished into performed fruit namely internal fruit, middle fruit and outer fruit as soon as each section contain parthenocarpy fruits. This research was conducted for determine composition and content fatty acid of oil at internal fruit, middle, outer and parthenocarpy fruit from oil palm fruit. Samples of fruit came from 3 – 5 spikelet the central of FFB. Result showed that oil content of outer fruit (46.9 + 9.9)% trend higher be compared middle fruit (42.8 + 10.3)% and internal fruit (39.1 + 9.5)%. Parthenocarpy fruits have a low oil content (14.2 + 16.2)% except yellowish fruit trend high relatively oil content. The main components of fatty acid at outer fruit, middle and internal are palmitic acid, oleic, linoleic and stearic with mean value respectively (44.8 – 45.8)%, (37.6 – 38.0)%, (9.9 – 10.9)% and (4.6 – 4.8)%. Oil content at parthenocarpy fruit have amount main component of fatty acid with performed fruit but composition of palmitic acid (40.0 + 5.9)% and oleic (34.6 + 8.4)% lower while linoleic acid (16.9 + 8.5)% and linolenic (1.6 + 1.8)% higher be compared to performed fruit. Simalungun variety has the highest oil content in the part of fruit, with that PPKS 540 and La Mé respectively. PPKS 540 variety has the highest oleic acid content while PPKS 718 has the highest linoleic content.

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