scholarly journals Study Of The Composition Of Solutions Used In Extracts Of Local Plants And Tannins

2021 ◽  
Vol 03 (04) ◽  
pp. 54-59
Author(s):  
Abrorjon Olimjon O’g’li Xomidjonov ◽  
◽  
Jamshid Faxriddin O’g’li Ergashev ◽  
Keyword(s):  
Mechanical Properties ◽  
Plant Extracts ◽  
Local Plants ◽  
Vegetable Tannins

In this article, tannins are substances that change the physicochemical and mechanical properties of the skin when exposed to it and turn the skin into leather. Vegetable tannins are commonly referred to as tannins. Both abroad and in our country, plant extracts are mainly used to soothe thick leather on the soles of shoes, technical leather, leather of belts and seams, leather of high boots and leather.

Influence of the micro-structural factors upon thermal and mechanical properties of various bag leathers

2017 ◽  
Vol 52 (3) ◽  
pp. 167-176 ◽  
Author(s):  
AK Mondal ◽  
PK Chattopadhyay
Keyword(s):  
Mechanical Properties ◽  
Morphological Characteristics ◽  
Crosslinking Density ◽  
Structural Factors ◽  
Melamine Formaldehyde ◽  
Elongation At Break ◽  
Indian Origin ◽  
Higher Temperature ◽  
Temperature And Pressure ◽  
Vegetable Tannins

Four different bag leathers, such as, Sheep Bag Leather (SBL), Buffalo Vegetable Tanned Leather (BVTL), Cow Drum Dyed Dry Milled Leather (CDDDML), and Cow Crocodile Print Leather (CCPL), were processed by different methods from respective wet-blues of Indian origin. Thermal degradation pro?le and mechanical properties of the samples were evaluated, and crosslink densities of each sample were measured by ?tment of Mooney-Rivlin equation on stress-strain plots. Morphological characteristics (e.g. ?bre structure, ?bre thickness, splitting etc.) of all the specimens were investigated by image analyses of SEM photomicrographs. The highest crosslinking density for BVTL was attributed to its higher ?bre and ?bril thicknesses coupled with rigorous retanning by vegetable tannins and syntans. Embossing at higher temperature and pressure reduced CCPL’s elongation-at-break value and hence stretchiness possibly due to the development of set properties within the CCPL matrix. SBL was noted to contain huge void spaces that increased its stretchiness, and melamine formaldehyde syntans showed pronounced in?uence in increasing the thermal resistance of both CCPL and CDDDML.Bangladesh J. Sci. Ind. Res. 52(3), 167-176, 2017

A Novel Hydrocolloid Film Based on Pectin, Starch and Gunnera tinctoria and Ugni molinae Plant Extracts for Wound Dressing Applications

2020 ◽  
Vol 20 (4) ◽  
pp. 280-292 ◽  
Author(s):  
Constanza Sabando ◽  
Walther Ide ◽  
Maité Rodríguez-Díaz ◽  
Gustavo Cabrera-Barjas ◽  
Johanna Castaño ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wound Healing ◽  
Bioactive Compounds ◽  
Water Uptake ◽  
Pressure Ulcer ◽  
Plant Extracts ◽  
Wound Dressing ◽  
Aqueous Media ◽  
Release Profile ◽  
Healing Property

Background: The biodegradable and biocompatible nature of pectin-based films is of particular interest in wound dressing applications, due to its non-toxicity, pH-sensitivity and gelling activity. An approach to improve the mechanical properties, the release profile of bioactive compounds as well as the performance in wet environments of pectin-based films is mixing with other biopolymers. Objective: To prepare hydrocolloid films based on crosslinked pectin / starch blend loaded with bioactive extracts from leaves of G. tinctoria and U. molinae with controlled release of bioactive compounds and healing property. Method: The hydrocolloid films were characterized by FTIR, SEM, and TGA-FTIR techniques and their tensile properties, water uptake, and polyphenolic release profile in aqueous media were evaluated. The dermal anti inflammatory activity of the hydrocolloid films was assessed by the mouse ear inflammation test. The wound healing property of the loaded hydrocolloid films was explored in a rat model and in a clinical trial (sacrum pressure ulcer). Results: The films showed an adequate water-uptake capacity between 100-160%. The release of active compounds from the hydrocolloid films followed the Korsmeyer-Peppas equation. The mechanical properties of hydrocolloid films were not affected by the plant extracts within the concentration range used. The incorporation of the bioactive extracts in the polysaccharide films inhibited the topical edematous response by about 50%. The topical application of the loaded hydrocolloid film on the pressure ulcer is completely closed after 17 days without showing any adverse reaction. Conclusion: A novel hydrocolloid matrix was produced from crosslinked starch-pectin, which exhibited suitable chemical-physical properties to be used as a carrier of plant extracts with wound healing properties.

scholarly journals Impact of Four Plant Extracts on Bactrocera dorsalis a Pest on Fruits

2021 ◽  
pp. 181-186
Author(s):  
Seema Ramniwas ◽  
Divya Singh
Keyword(s):  
Plant Extract ◽  
Plant Extracts ◽  
Larval Mortality ◽  
Bactrocera Dorsalis ◽  
Study Results ◽  
Mentha Longifolia ◽  
Ocimum Tenuiflorum ◽  
Local Plants ◽  
Bougainvillea Glabra ◽  
Third Instar Larvae

Menthol extracts of four local plants (Ocimum tenuiflorum, Hibiscus, Mentha longifolia and Bougainvillea glabra) were analysed to check their toxicity on third instar larvae of B. dorsalis by estimating the larval mortality for four plant extracts and different times exposure (1-5 hr) and measured LT50 value for each plant extract. Larval mortality varies for extract of each studied plant as Ocimum tenuiflorum showed its highest value of 56.68% at 4.57hr, for hibiscus it was 72% at 3.5 hr., for Mentha longifolia it was 95.23% at 4 hr., while for Bougainvillea glabra it was 100% at 2 hr. exposure. The LT50 values for B. dorsalis varying from 1.011 for Bougainvillea glabra to 2.946 for Ocimum tenuiflorum whereas LT50 values were 1.402 and 1.123, forHibiscus and Mentha longifolia respectively. Present study results showed that Bougainvillea glabra was highly toxic whereas Ocimum tenuiflorum shows least toxicity.

scholarly journals Removal of Listeria monocytogenes Biofilm with Some Local Plant Extracts of Kurdistan Region

2019 ◽  
Vol 7 (2) ◽  
pp. 1-4
Author(s):  
Srwa A. Mohammed
Keyword(s):  
Listeria Monocytogenes ◽  
Plant Extract ◽  
Plant Extracts ◽  
Antimicrobial Agents ◽  
Punica Granatum ◽  
Kurdistan Region ◽  
Planktonic Cells ◽  
Biofilm Production ◽  
Local Plant ◽  
Local Plants

The results of removing or reducing biofilm were determined using subinhibitory concentrations (SICs) of some local plants in the flora of Kurdistan region of Iraq on biofilm production in Listeria monocytogenes. About 10–500 µg/ml of the plant extracts were used against growth and biofilm production in tissue culture plates which were measured spectroscopically. The SIC effects of each of Eugenia caryophyllata (Clove) and Rhus glabra (Sumac) have significantly affected on planktonic cells and reduced sessile cells or biofilm formation in L. monocytogenes. Remarkably, the data showed strong biofilm reduction under synergistically effect of the plant extract mixed with the antimicrobial agents in multidrugresistant L. monocytogenes. Whereas the SIC some of other plant extracts such as Salix candida and pomegranate (Punica granatum) have significantly enhanced biofilm expression in L. monocytogenes, but the use of these extracts synergistically with some antibiotics also resulted in inhibition of biofilm in comparison to merely use of either the extracts or antibiotics. The result of statistical analyses shows that P > 0.05. The results showed that the combination of plant extract with antibiotic together has more effect than using plant merely.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

Effects of cooling rate on the mechanical properties of dual phase treated vanadium steels

1983 ◽  
Vol 41 ◽  
pp. 220-221
Author(s):  
L.J. Chen ◽  
H.C. Cheng ◽  
J.R. Gong ◽  
J.G. Yang
Keyword(s):  
Mechanical Properties ◽  
Cooling Rate ◽  
Automobile Industry ◽  
High Strength ◽  
Weight Percent ◽  
Low Alloy Steels ◽  
Dual Phase ◽  
Resource Requirement ◽  
Alloy Steels ◽  
Potential Weight

For fuel savings as well as energy and resource requirement, high strength low alloy steels (HSLA) are of particular interest to automobile industry because of the potential weight reduction which can be achieved by using thinner section of these steels to carry the same load and thus to improve the fuel mileage. Dual phase treatment has been utilized to obtain superior strength and ductility combinations compared to the HSLA of identical composition. Recently, cooling rate following heat treatment was found to be important to the tensile properties of the dual phase steels. In this paper, we report the results of the investigation of cooling rate on the microstructures and mechanical properties of several vanadium HSLA steels.The steels with composition (in weight percent) listed below were supplied by China Steel Corporation: 1. low V steel (0.11C, 0.65Si, 1.63Mn, 0.015P, 0.008S, 0.084Aℓ, 0.004V), 2. 0.059V steel (0.13C, 0.62S1, 1.59Mn, 0.012P, 0.008S, 0.065Aℓ, 0.059V), 3. 0.10V steel (0.11C, 0.58Si, 1.58Mn, 0.017P, 0.008S, 0.068Aℓ, 0.10V).

Lattice Imaging of Grain Boundaries in Ceramics

1977 ◽  
Vol 35 ◽  
pp. 114-115
Author(s):  
D. R. Clarke ◽  
G. Thomas
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Silicon Nitride ◽  
Grain Boundaries ◽  
High Temperature Strength ◽  
Current Interest ◽  
Lattice Imaging ◽  
Special Significance ◽  
Structural Applications ◽  
Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

1982 ◽  
Vol 40 ◽  
pp. 680-681
Author(s):  
Li Li-Sheng ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Microscopic Observation ◽  
Electron Microscopic Observation ◽  
Electron Microscopic ◽  
Aromatic Polyamides ◽  
Radial Arrangement ◽  
Scanning Electron ◽  
Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

1976 ◽  
Vol 34 ◽  
pp. 592-593
Author(s):  
Ernest L. Hall ◽  
J. B. Vander Sande
Keyword(s):  
Mechanical Properties ◽  
Single Crystal ◽  
Dislocation Structure ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Strain Curve ◽  
Optical Devices ◽  
Semiconductor Compound ◽  
Wide Range ◽  
Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

TEM Studies of Grain Boundary Films in Si3N4 Ceramics

1991 ◽  
Vol 49 ◽  
pp. 930-931
Author(s):  
H.-J. Kleebe ◽  
J.S. Vetrano ◽  
J. Bruley ◽  
M. Rühle
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Silicon Nitride ◽  
Hot Isostatic Pressing ◽  
Amorphous Film ◽  
Liquid Phase Sintering ◽  
Second Phase ◽  
High Temperature Mechanical Properties ◽  
Triple Points ◽  
Boundary Films

It is expected that silicon nitride based ceramics will be used as high-temperature structural components. Though much progress has been made in both processing techniques and microstructural control, the mechanical properties required have not yet been achieved. It is thought that the high-temperature mechanical properties of Si3N4 are limited largely by the secondary glassy phases present at triple points. These are due to various oxide additives used to promote liquid-phase sintering. Therefore, many attempts have been performed to crystallize these second phase glassy pockets in order to improve high temperature properties. In addition to the glassy or crystallized second phases at triple points a thin amorphous film exists at two-grain junctions. This thin film is found even in silicon nitride formed by hot isostatic pressing (HIPing) without additives. It has been proposed by Clarke that an amorphous film can exist at two-grain junctions with an equilibrium thickness.

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