Effect of original structure on the strengthening process and the properties of bands of alloy 36NKhTYu

1978 ◽  
Vol 20 (5) ◽  
pp. 385-390
Author(s):  
N. M. Vorontsov ◽  
V. K. Shugaenko ◽  
P. E. Drapiko ◽  
L. E. Chernyakova ◽  
R. F. Patseka
Keyword(s):  
Original Structure ◽  
Alloy 36Nkhtyu

Reed (Phragmites australis agg.) dominated plant communities in the Lower Volga Valley

2015 ◽  
pp. 26-37
Author(s):  
V. B. Golub ◽  
V. V. Bondareva ◽  
A. N. Sorokin ◽  
L. F. Nikolaychuk
Keyword(s):  
Expert System ◽  
Phragmites Australis ◽  
Plant Communities ◽  
Floristic Composition ◽  
Original Data ◽  
Optimal Level ◽  
Point Of View ◽  
Original Structure ◽  
Volga River ◽  
Lower Volga

Plant communities with reed domination (Phragmites australis agg.) occupy the large areas in the Lower Volga Valley and especially in the river delta. We have set the task to reveal the diversity of these communities in the Lower Volga Valley. For this purpose, we applied the database that is registered in the Global Index of Vegetation-Plot Databases (GIVD) under the EU-RU–002 index (http://www.givd.info/) and includes 14871 relevés made during the period from 1924 to 2013. Communities with the dominance of reed were defined as such, if the coverage of this plant was more than 50 %. We have found 375 such relevés in the database. At first, one basal community, 3 associations and 3 subassociations with domination of Phragmites australis agg. were distinguished in the Lower Volga Valley. All processing and analysis of relevés were performed using the software package JUICE 7.0. (Tichý, 2002). The «Cocktail» method was applied to establish the sociological groups that indicate environmental conditions (Bruelheide, 2000). The expert system for selection from the database of relevés by means of these groups was created. It is allowed us to ascribe relevés to earlier distinguished associations, subassociations and basal community. 171 relevés have been identified by the expert system and they were assigned to association, subassociation or the basal community. 204 relevés were not referred to any association, subassociation or the basal community. We wanted to answer the question: are there among these 204 relevés, which could be interpreted as the new syntaxa, giving them the proper ecological characteristics? For this purpose, the cluster analysis of 204 relevés has been carried out. The optimal level of clustering was determined by calculating the index of “crispness of classification” (Botta-Dukát et al., 2005). The greatest “crispness of classification” was reached at allocation of 13 clusters. Consideration of the floristic composition of allocated groups had shown that 11 of them were the transitional plant communities among the earlier established syntaxa. Only two clusters were differed in rather original structure that we could explain by the influence of environment factors. We have identified them as new associations Rubio tataricae-Phragmitetum australis and Cynancho acuti-Phragmitetum australis. All associations with the dominance of Phragmites australis agg. distinguished in the Lower Volga Valley were included in the alliance Phragmition communis Koch 1926, order Phragmitetalia communis Koch 1926. In literary sources from the ecological point of view these syntaxa are defined as the wetland communities, which are closely linked to water bodies (Šumberová et al., 2011; Ermakov, 2012). However, in many cases this definition does not correspond to the ecology of plant communities with the dominance of reed in the lower reaches of the Volga River. Ecotops of these communities are flooded for up to 2–3 months in a year and then they dry out. In the autumn, the ground water level can drop to a depth of one meter (Golub et al., 2011). The plant satellites of the reed here are often mesophytic plants such as Rubus caesius, Calamagrostis epigeios, Phalaris arundinacea, Rubia tatarica, Althaea officinalis, and Rumex stenophyllus. Therefore, the inclusion of phytocoenosises with domination of the reed in the lower reaches of the Volga River in the alliance Phragmition communis is rather relative. A correct placement of these plant communities in the system of vegetation syntaxa of the arid areas can be made only if it is based on original data obtained from much bigger territory than the Lower Volga Valley. In future geobotanical studies, it is desirable to divide the aggregation of Phragmites australis agg. into smaller species taxa.

Diseases Prevention by Water Defluoridation Using Hydrotalcites as Decontaminant Materials

2017 ◽  
Vol 68 (1) ◽  
pp. 168-171 ◽  
Author(s):  
Letitia Doina Duceac ◽  
Cristina Elena Dobre ◽  
Ioana Pavaleanu ◽  
Gabriela Calin ◽  
Simona Nichitus ◽  
...  
Keyword(s):  
Dental Fluorosis ◽  
Precipitation Method ◽  
Original Structure ◽  
Fluoride Removal ◽  
Major Goal ◽  
Bone Stiffness ◽  
Morphological Aspects ◽  
Adsorption Capacities ◽  
Interlayer Structure ◽  
Co Precipitation

Preventing diseases is deemed to be the major goal of our century especially when an excessive fluoride in drinking water can cause dental fluorosis, bone stiffness, rheumatism and skeletal fluorosis. Fluoride uptake from groundwater implies a worldwide multidisciplinary effort in order to develop renewable, cheap, human friendly materials. Among other materials, hydrotalcites could be good candidates for an efficient fluoride removal from water due to their adsorption, anion exchange and reconstruction properties. These nanostructured materials were synthesized using co-precipitation method in controlled conditions. Presence of anions in the interlayer structure and morphological aspects were performed by FTIR and SEM techniques. Thermal treatment of hydrotalcites showed good adsorption capacities for water defluoridation mostly due to their tendency to restore the original structure.

scholarly journals Numerical Study of Thermal-Hydraulic Performance of a New Spiral Z-Type PCHE for Supercritical CO2 Brayton Cycle

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4417
Author(s):  
Tingting Xu ◽  
Hongxia Zhao ◽  
Miao Wang ◽  
Jianhui Qi
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Pressure Loss ◽  
Numerical Study ◽  
Hydraulic Performance ◽  
Optimal Structure ◽  
Original Structure ◽  
Brayton Cycle ◽  
Compact Structure ◽  
Spiral Angle

Printed circuit heat exchangers (PCHEs) have the characteristics of high temperature and high pressure resistance, as well as compact structure, so they are widely used in the supercritical carbon dioxide (S-CO2) Brayton cycle. In order to fully study the heat transfer process of the Z-type PCHE, a numerical model of traditional Z-type PCHE was established and the accuracy of the model was verified. On this basis, a new type of spiral PCHE (S-ZPCHE) is proposed in this paper. The segmental design method was used to compare the pressure changes under 5 different spiral angles, and it was found that increasing the spiral angle θ of the spiral structure will reduce the pressure drop of the fluid. The effects of different spiral angles on the thermal-hydraulic performance of S-ZPCHE were compared. The results show that the pressure loss of fluid is greatly reduced, while the heat transfer performance is slightly reduced, and it was concluded that the spiral angle of 20° is optimal. The local fluid flow states of the original structure and the optimal structure were compared to analyze the reason for the pressure drop reduction effect of the optimal structure. Finally, the performance of the optimal structure was analyzed under variable working conditions. The results show that the effect of reducing pressure loss of the new S-ZPCHE is more obvious in the low Reynolds number region.

Preparation and thermostability of hydrophobic modified nanocrystalline cellulose

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Junliang Lu ◽  
Jinyan Lang ◽  
Na Wang ◽  
Xinhui Wang ◽  
Ping Lan ◽  
...  
Keyword(s):  
Stearic Acid ◽  
Palmitic Acid ◽  
Lauric Acid ◽  
Morphological Structure ◽  
Strong Stability ◽  
Nanocrystalline Cellulose ◽  
Original Structure ◽  
Optimal Conditions ◽  
Reaction Conditions ◽  
New Approach

Abstract In this paper, we provide a new approach for the anionic modification and functional application of nanocellulose. The nanocrystalline cellulose (NCC) is prepared from microcrystalline cellulose (MCC) and modified by fatty acids (lauric acid, palmitic acid and stearic acid). Ammonium ceric sulfate or hydrogen peroxide/ferrous sulfate being used as an initiator, three kinds of modified nanocrystalline cellulose (MNCC) can be synthesized at low temperature. The terminology for these MNCC is L-MNCC (NCC modified by lauric acid), P-MNCC (NCC modified by palmitic acid) and S-MNCC (NCC modified by stearic acid). Compared with those existing synthesized methods, the reaction condition is mild, and the modified products show strong stability. It can be seen from morphological structure analysis and reaction conditions analysis of MNCC that the original structure of cellulose is changed slightly. And the optimal conditions for preparing MNCC are obtained. The best yields of L-MNCC, P-MNCC and S-MNCC are 54.2 %, 20.9 % and 14.5 %, respectively.

scholarly journals IX. On the conversion of the substance of a bird into a hard fatty matter. In a letter from Thomas Sneyd, Esq. to Sir Joseph Banks, Bart. P. R. S

1792 ◽  
Vol 82 ◽  
pp. 197-198
Keyword(s):  
Great Part ◽  
Original Structure ◽  
Fatty Matter ◽  
Different Parts ◽  
General Appearance

Sir, I Take the liberty of sending you two or three pieces of a bird whose substance has been converted into a hard fatty matter, which I found at the head of a fish pool, where a small brook runs into it, lying under water upon the mud. When first taken out, it was almost entire, and had several feathers sticking in different parts of the skin, which have since fallen out; a little down, however, still adheres to the smaller specimen. From the size, and general appearance of the bird, I conjectured it to be a duck, or young goose; but before I had time to give it a particular examination, it was unfortunately broken in pieces, and the greatest part destroyed. The skin in the piece which was saved is of different thicknesses, in some parts a full quarter of an inch; it has retained its original structure exactly, but is in great part separated from the flesh, though both of them are now composed of the same fat matter. This substance resembles spermaceti in its consistence' between the teeth, but has neither taste nor smell; it melts in a small heat, and when congealed again, becomes more solid, and looks like wax; in a greater heat it burns, and emits a strong animal smell. As I never heard or perceived that the water in which this bird lay has any particular property, I am inclined to think that it has undergone this singular change while buried in the mud, and that the brook had afterwards washed it up, and carried it into this pool. I am sorry that the specimen and my account of this singular metamorphosis are so imperfect. The analogy which the case bears to the change of human bodies, observed by M. Fourcroy * in the Cemetery des Innocents , is my chief reason for offering them to you; and if they should be deemed worthy of the notice of the illustrious Society over which you preside, you are at liberty to present them.

Application of viscous dampers for structural response reduction in building renovation

2021 ◽  
Author(s):  
Hu Daohang ◽  
Zhao Xin
Keyword(s):  
Dynamic Response ◽  
Structural Response ◽  
Seismic Energy ◽  
Original Structure ◽  
Viscous Dampers ◽  
Structural Reinforcement ◽  
Analysis Methods ◽  
Direct Integration Method ◽  
Calculation Results ◽  
Plane Frame

<p>This paper introduces a new idea in the reconstruction and continuation projects. By arranging damping devices, the additional damping of the structure is increased, thereby reducing the dynamic response of the structure under the new seismic precautionary criterion. This paper focuses on the study of viscous dampers which one of the damping device, introduces the energy dissipation principle of viscous dampers, and combines a two-story plane frame case to analyze and compare the dynamic response between non-damping structure and damping structure. The location and quantity of the arrangement were compared with multiple models. Through analysis, it can be seen that by equipping with viscous dampers, seismic energy can be effectively dissipated, thereby reducing the workload of structural reinforcement and having less impact on the original structure. Finally, two commonly analysis methods in damping structures are studied, direct integration method and fast nonlinear analysis (FNA), the main differences between the two analysis methods are introduced, and the calculation results of the two methods are compared and analyzed.</p>

scholarly journals Validation and invariance across gender of the Beliefs About Appearance Scale (BAAS) in a community sample of heterosexual adults in a committed relationship

2018 ◽  
Vol 40 (2) ◽  
pp. 126-135
Author(s):  
Patrícia M. Pascoal ◽  
Maria-João Alvarez ◽  
Magda Sofia Roberto
Keyword(s):  
Factor Analysis ◽  
Confirmatory Factor Analysis ◽  
Community Sample ◽  
Reliability And Validity ◽  
Two Dimensions ◽  
Original Structure ◽  
Confirmatory Factor Analyses ◽  
Factorial Model ◽  
Confirmatory Factor ◽  
Body Appearance

Abstract Objective To evaluate the psychometric properties of the Beliefs About Appearance Scale (BAAS) in terms of its factorial structure and invariance, reliability, and validity when applied to adults from the community. Methods Participants consisted of 810 heterosexual Portuguese individuals in a committed relationship. As a confirmatory factor analysis did not support the original structure of the BAAS, an exploratory factor analysis was performed. Results A 12-item version was extracted comprising two dimensions: one personal and the other social. The factorial model depicting this bidimensional structure revealed an adequate fit following confirmatory factor analysis. Multigroup confirmatory factor analyses indicated invariance across gender. Concurrent and discriminant validities and internal consistency were estimated and observed to be adequate. Conclusions This shorter measure of the BAAS can accurately assess body appearance beliefs and may be used in different research settings and contexts.

scholarly journals AUTOMORPHISM GROUPS OF RANDOMIZED STRUCTURES

2017 ◽  
Vol 82 (3) ◽  
pp. 1150-1179 ◽  
Author(s):  
TOMÁS IBARLUCÍA
Keyword(s):  
Automorphism Group ◽  
Automorphism Groups ◽  
Original Structure ◽  
Polish Groups ◽  
Separable Models

AbstractWe study automorphism groups of randomizations of separable structures, with focus on the ℵ0-categorical case. We give a description of the automorphism group of the Borel randomization in terms of the group of the original structure. In the ℵ0-categorical context, this provides a new source of Roelcke precompact Polish groups, and we describe the associated Roelcke compactifications. This allows us also to recover and generalize preservation results of stable and NIP formulas previously established in the literature, via a Banach-theoretic translation. Finally, we study and classify the separable models of the theory of beautiful pairs of randomizations, showing in particular that this theory is never ℵ0-categorical (except in basic cases).

A Seismic Effective Method for Double-Layer Reticulated Shell Using Buckling-Restrained Braces

2010 ◽  
Vol 163-167 ◽  
pp. 2852-2856
Author(s):  
Chang Wu ◽  
Xiu Li Wang
Keyword(s):  
Double Layer ◽  
Seismic Performance ◽  
Linear Time ◽  
Ground Motions ◽  
Equations Of Motion ◽  
Time History ◽  
Original Structure ◽  
Loading Test ◽  
Strong Earthquakes ◽  
Buckling Restrained Braces

In this study a kind of buckling-restrained braces (BRBs) as energy dissipation dampers is attempted for seismic performance of large span double-layer reticulated shell and the effectiveness of BRBs to protect structures against strong earthquakes is numerically studied. The hysteretic curve of such members is obtained through the simulation of the cyclic-loading test, and the equations of motion of the system under earthquake excitations are established. BRBs are then placed at certain locations on the example reticulated shell to replace some normal members, and the damping effect of the two installation schemes of BRBs is investigated by non-linear time-history analyses under various ground motions representing major earthquake events. Compared with the seismic behavior of the original structure without BRBs, satisfactory seismic performance is seen in the upgraded models, which clarifies the BRBs can reduce the vibration response of spatial reticulated structure effectively and the new system has wide space to develop double layer reticulated shell.

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