Comparative Investigation of Plastic Properties and Water Permeance of Cement-Lime Mortars and Cement-Lime Replacement Mortars

Author(s):  
MP Schuller ◽  
RSK van der Hoeven ◽  
ML Thomson

The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.


Author(s):  
Dmitry Olegovich Bokov ◽  
Tatyana Yuryevna Kovaleva ◽  
Valentina Alekseevna Ermakova ◽  
Daria Aleksandrovna Trashchenkova ◽  
Ekaterina Anatolievna Dorovskih ◽  
...  

Filipendula ulmaria (L.) Maxim. (Meadowsweet) is known in traditional medicine as anti-inflammatory, wound-healing,astringent and antibacterial remedy. However recent studies show that it also has neurotropic activity. In Russia meadowsweet flowers are used as crude herbal drugs (temporary pharmacopoeial monograph 42-1777-87), also leafs and herb are used in the traditional medicine. Objective of the study was to carry out comparative investigation of composition and content of major biologically active compounds (BAC) in Filipendula ulmaria herb, flowers and leafs by thin-layer chromatography, differential spectrophotometry with aluminum chloride reagent (total flavonoids in terms of rutoside), gravimetry (total extractives, extracted by water), permanganatometric titration (total tannins in terms of tannin). Rutoside, tannin, gallic acid and salicylic acid were identified in Filipendula ulmaria herb, flowers and leafs by TLC. Also we analyzed content of substances extracted by water, flavonoids and tannins. Total extractives, extracted by water in F. ulmaria herb is 13.12±0.10%, in leafs – 13.98±0.37%, in flowers – 18.09±0.17%. Total tannins in F. ulmaria herb is 11.87±0.47%, in leafs – 12.06±0.18%, in flowers – 12.26±0.29%. Total flavonoids in F. ulmaria herb 4.34±0.17%, in leafs – 6.98±0.23%, in flowers – 11.75±0.57%. The obtained data will be used for development of a pharmacopoeial monograph project "Filipendula ulmaria (L.) Maxim., herba" for inclusion in the State Pharmacopoeia of the Russian Federation.


2020 ◽  
Vol 2020 (12) ◽  
pp. 13-17
Author(s):  
Nikolay Proskuryakov ◽  
Uliana Putilova ◽  
Rasul Mamadaliev ◽  
Oleg Teploukhov

The comparative investigation results of AD33 aluminum alloy welded joint quality dependence upon changes in a laser beam motion rate for conditions of hand and automatic laser welding are shown. A micro-structure of a welded joint at the hand and automatic laser welding of the AD33 alloy is investigated.


The author presented experimental data on the influence of technological factors on the quality indexes of tablets based on a cryoliofilized salmonella bacteriophage. The analysis of the technological properties of model granules with such parameters as bulk density, flow ability, vibration compacting index, Hausner index, Сarr's index showed that the fractional composition of the granules should contain no more than 33 % of the pulverized fraction (0,25 mm or less). The granulate, regardless of its fractional composition, has elastic-plastic properties characterizing the strength of the tablets. The influence of the pressing pressure of the cryoliofilized composition tablets with salmonella bacteriophage on the crush strength and disintegration of enteric-soluble tablets was studied. The optimum compression pressure of tablets within 60 mPa of granules with a content of pulp fraction (0.25 mm or less) is not to be higher than 33 %.


1990 ◽  
Vol 45 (6) ◽  
pp. 602-606 ◽  
Author(s):  
B. Merkel ◽  
J. Reichling

Abstract Unorganized callus and leaf/root-differentiating callus cultures of Pimpinella major have been established in liquid nutrient medium. Their capacity to accumulate rare phenylpropanoids such as epoxy-pseudoisoeugenol tiglate, epoxy-anol tiglate and anol tiglate was compared with that of seedlings and whole plants. The unorganized callus cultures were not able to accumulate any phenylpropanoids. In comparison, the leaf/root-differentiating callus culture promoted the accumulation of epoxy-pseudoisoeugenol tiglate (up to 90 mg/100 g fr.wt.) but not that of anol-derivatives. The accumulated amount of EPT in PMD-SH was comparable with that in plant seedlings.


2020 ◽  
Vol 992 ◽  
pp. 498-503
Author(s):  
S. Sidelnikov ◽  
D. Voroshilov ◽  
M. Motkov ◽  
M. Voroshilova ◽  
V. Bespalov

The article presents the results of studies on the production of wire with a diameter of 0.5 mm from aluminum alloy 01417 with a content of rare-earth metals (REM) in the amount of 7-9% for aircraft construction needs. The deformation modes, the experimental technique and equipment for the implementation of the proposed technology described. The wire was obtained by drawing and bar rolling with subsequent drawing from a rod with a diameter of 5 mm, obtained previously using the process of combined rolling-extruding (CRE) from a continuous ingot with a diameter of 12 mm, cast in an electromagnetic mold (EMM). The wire obtained by the presented technology was subjected to 4 different heat treatment modes with annealing temperatures from 350 to 500 °C and holding time of 1 h in the furnace to achieve mechanical and electrophysical properties corresponding to TS 1-809-1038-2018. The level of strength and plastic properties obtained in the course of research required only one intermediate annealing. The microstructure of the wire was investigated and the modes were revealed that made it possible to obtain the required level of mechanical properties and electrical resistivity, satisfying TS 1-809-1038-2018.


2021 ◽  
Vol 298 ◽  
pp. 123881
Author(s):  
M. Stefanidou ◽  
V. Kamperidou ◽  
A. Konstantinidis ◽  
P. Koltsou ◽  
S. Papadopoulos

Author(s):  
Georgia Colleluori ◽  
Jessica Perugini ◽  
Giorgio Barbatelli ◽  
Saverio Cinti

AbstractThe mammary gland (MG) is an exocrine gland present in female mammals responsible for the production and secretion of milk during the process of lactation. It is mainly composed by epithelial cells and adipocytes. Among the features that make the MG unique there are 1) its highly plastic properties displayed during pregnancy, lactation and involution (all steps belonging to the lactation cycle) and 2) its requirement to grow in close association with adipocytes which are absolutely necessary to ensure MG’s proper development at puberty and remodeling during the lactation cycle. Although MG adipocytes play such a critical role for the gland development, most of the studies have focused on its epithelial component only, leaving the role of the neighboring adipocytes largely unexplored. In this review we aim to describe evidences regarding MG’s adipocytes role and properties in physiologic conditions (gland development and lactation cycle), obesity and breast cancer, emphasizing the existing gaps in the literature which deserve further investigation.


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