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Tensile And Flexural Properties Of Delaminated Woven E-Glass/Epoxy Composites
No full textThe woven E-glass/epoxy composite with circular artificial defect located at enter position between first and second plies was manufactured using hand lay-up method. The composite consisted of twelve layers of glass cloth. Experiments were
conducted in tension and flexure with four-point loading to determine the behavior of laminate. The results were compared with those of laminates without artificial defect. A knee was observed on the load displacement curve for the laminate without defect loaded in tension. Results show that the defect does not affect considerably the tensile strength of the composite and the existence of defect influences highly the flexural properties
Experimental Surface Quality Estimation In Ultrasonic Vibration Assisted Helical Milling
No full textSurface quality is a vital aspect to assess the eminence of products that chooses wear and also stimuli quality of assemblies. The research journal article is focused to estimate the surface quality during helical milling with ultrasonic
vibration assistance to workpiece. This study presents an investigation of surface eminence on ultrasonic machining (UM) of difficult to cut material of D2 steel, an effort was made for modeling response i.e. surface roughness(Ra) in UM technique
by means of DESIGN EXPERT software. Three operational factors i.e. spindle speed(N), axial depth(ap) each at two levels and orbital speed(nc) of four levels were varied to investigate surface quality variations with respect to levels of operational
factors. The ANOVA was performed to ascertain importance of model established. The testings outcomes confirms validity and competence of model developed
A Study Of Hardness And Microstructure Of A Robot Deposited Waam Component With Varying Wire Feed Rate In The Build Direction
No full textWire Arc Additive Manufacturing an arc based metal additive manufacturing creates 3D components with layer by layer weld depositions has a lot of advantages over powder based techniques and has the capability of fabricating medium to large
components . The present work focussed on the study of the microstructure and hardness for wall structure fabricated by weld depositions based on Wire Arc Additive Manufacturing technique with different wire feed rates utilized from bottom
to top in the build direction. Component fabricated is with 3 slabs with different wire feed rate in each slab and these slabs are deposited with multiple beads and multiple layers by using ABB 6 – AXIS Industrial Robot 1520ID. It is observed that internal
matrix irrespective of slabs has insignificant variations in the hardness of the material in the build direction. The icrostructure characterization exposes typically a homogenous polygonal ferrite with perlite. In general the overall process looks to
be stable with negligible hardness variation. The core idea of this paper is to understand the microstructure and hardness of as-built WAAM components with varying feed rates
Development and Validation for Simultaneous Estimation of Perindopril and Indapamide by UPLC-UV in Tablet Dosage form
Get PDFAn ultra-performance liquid chromatography (UPLC) method with UV detection was developed for simultaneous estimation of Perindopril and Indapamide in tablet dosage form of pharmaceutical formulation. Simultaneous determination of both drugs is highly significant as this would tolerate more effective generation of clinical data and could be more cost-effective than distinct assays. The chromatography was carried out at 25 °C using an isocratic mobile phase consisting of buffer (0.1% ortho phosphoric acid in Water v/v) and acetonitrile in the ratio of 45:55% (v/v) using variable wavelength UV– Vis detector set at 254nm. Perindopril and Indapamide were eluted isocratically at a steady flow rate of 0.3mL/min, indicated reasonable good assay parameters. The retention times were around 0.8 min and 1.1 min, asymmetry factors 1.7 and 1.6, and linearity correlation coefficients were in the range 20 - 120 and 6.25 - 37μg/ml, respectively. Regression coefficient was
0.999 for both the compounds, while recovery from samples were 98.09-100.17 and 99.06–99.99% for Perindopril and Indapamide, respectively. Relative standard deviations (RSD) of intra- and inter-day precisions were < 2% for both the drugs. Specificity/selectivity experiments revealed the absence of interference from excipients. From the above parameters indicated that the present developed method is precise, accurate, reproducible and specific for desired drug analysis. Moreover, it can also be used for routine simultaneous
estimation of Perindopril and Indapamide in combinations tablets of pharmaceutical drug products
RECENT STRATEGIES FOR EFFICIENT SYNTHESIS AND BIOLOGICAL ACTIVITIES OF COUMARIN-CHALCONE DERIVATIVES
Get PDFCoumarins and chalcones are potential pharmacological and biologically active molecules obtained from the natural source. Coumarins have predominant pharmacological activities such as antidiabetic, antitumor, and anti-inflammatory activity. Chalcones are also one of the naturally occurring pharmacologically vital molecules with different activities such as anti-inflammatory, antitumor, antimicrobial, and antimalarial activity. Literature reveals that a huge number of coumarinyl chalcone derivatives have various pharmacological activities. Coumarinyl chalcone derivatives gained more prominence due to their significant biological activities. This work explains the current information about synthesis techniques, pharmacological importance, and clinical applications of coumarinyl chalcone derivatives
Synthesis and structural characterization of the formato bridged Cu(II) cubane: Crystallographic evidence of atmospheric CO2 fixation as formate in a tertranuclear Cu(II) cluster, .
Get PDFa b s t r a c t
Fixation of atmospheric carbon-di-oxide (CO2) by metal complexes continuously receives a great deal of attention from the viewpoint of environmental concerns. Herein, a novel tetranuclear copper (II) clus�ter [Cu4 μ3-(mph)4 μ2-(HCO2)2] (ClO4)2.CH2Cl2 (1), synthesized using Methyl(6-hydroxymethyl)picolinate ligand (Hmhp) and Cu(ClO4)2·6H2O in the presence of triethylamine base, is reported where atmospheric CO2 is serendipitously trapped in the form of formato-bridging ligand. The single X-ray structural eluci�dation of the complex 1 reveals a Cu4O4 cubane cluster stabilized by four peripheral mhp ligands, all of which display μ3-η1: η1: η3 binding mode (each bridging ligand link three Cu (II) ions). Moreover, the cubane core was supported by two bridging formate groups, resulted from the reduction of atmospheric
CO2. The two formate ions exhibit μ2-η1: η1 binding mode, bridges two Cu(II) atoms. All the Cu(II) ions in the cubane core possess distorted octahedral coordination geometry (CuN1O5). Based on the observed Cu···Cu interactions in the Cu4O4 cubane core, 1 can be categorized under [2+2+2] type of classification.
In addition to the synthesis and characterization of 1, a mechanistic hypothesis for the reduction of at�mospheric CO2 to formate is also proposed to highlight the future potential of similar complexes in CO2 fixation/conversio
Influence of MWCNTs on the MechanicalProperties of Continuous Carbon EpoxyComposites
No full textThe Carbon fiber reinforced epoxy composites finds wide range of applications in various fields such as aerospace, defence etc. The present study focuses on fabrication and
mechanical characterization of different ply oriented Continuous Carbon Fibre reinforcedepoxy composites (CCFE). CCFE composites were fabricated using Drum winding, Hand Lay Up (HLU) followed by Compression Moulding with (0°)4,
(0°/90°/0°/90°)4, (45°)4 orientations. Mechanical haracterisation was performed on the fabricated composites as per ASTM standards. CCFE with (0°/90°/0°/90°)4 orientation exhibited better compressive strength over other composites. 0.5,1.5 weight % of Multi Walled Carbon Nano-Tubes (MWCNTs) were reinforced in to the epoxy resin using ultrasonicator. The resin mixture with 0.5, 1.5 weight % of MWCNTs was used as matrix
for the fabrication of (0°/90°/0°/90°)4 composites. Tensile, Compression, Flexural, Impact, Hardness and Water absorption tests were performed to investigate the effect of MWCNTs on (0°/90°/0°/90°)4 composites. CCFE samples with MWCNTs at 0.5% exhibited 1.63%, 5.23%, 16.47%, 3.9%, 29.6% increment in tensile strength, compressive strength, ILSS, impact strength, hardness, water absorptionand 36.9% decrement in flexural strengt
Hydrological Modelling of Catchments at Industrial Sector
No full textIn any nation industries are the major sources for the
country economy and also the major source of employment for the people of any nation. Industries are also considered as prime reason for the developmental activities with huge employment potential at the other side the environmental conditions in and around the industries are degrading very rapidly due to the lack of proper supervision on disposal of industrial wastes along with the emissions releasing into the open atmosphere by few of the industries [9] without any concern of human health eventually over a period of time all the effluents and the emissions released into the open atmosphere without treatment shows dangerous consequences on the environment in the society. The major requirements of any industries starts with water only, as the water is prime element for the survival any living organism on the earth and also the water is the prime component for the development of
any area but at certain areas the water both surface and ground
water [11] sources have been contaminating due to the unethical and unscientific disposal of wastes into the open lands as well as into the nearby water bodies. when we emphasize the reason behind this specific activity we came to understand that improper maintenance of effluent treatment plants and the effluents releasing from them shows its severe impacts on nearby aquatic organisms [3], if the same water is used for domestic activities there will be a damage for human health and sometimes it may leads to the death of the individuals also. In the present study three locations were indentified around the boundaries [8] of catchment based on the entry of flow into the catchments and the samples were collected for three times in the study period of three months, all the samples were marked with labels and analysis [2] was carried out by using prescribed analytical procedures, the results were compared with surface water quality standards [1] specified by Central Pollution Control Board,1979 and the Bureau of Indian standards, 1982 to find out the hydrology of the catchmen
Rapid Environmental Impact Assessment of Lake Water
No full textPollutants can be classified into different categories based on their source of origin normally the pollutants of water contamination comes either by through wind erosion gully
erosion along with the activities like surface runoff or agricultural runoff etc., whatever the reason of lake contamination as per the current scenario of water availability there is an immediate need to conserve water to a great extent for the sustainable development from the local to regional and national level. Lakes are considered as potential resources for both domestic and agricultural utilization, which will maintain surplus quantity of water irrespective of season but now a days the existence of water in the lakes is not happening due
to the increased consumption levels of water for various activities of the water demand, rapid industrialization, unplanned urbanization and pesticide usage in the agricultural practices has lead to contamination of waters. By keeping in this view, the present study is carried out with the main objective of rapid environmental assessment of nethaji nagar lake (cheruvu)
waters. The study of nethaji nagar lake (cheruvu) waters quality was assessed by three times during three months period. The study included Physico-Chemical quality parameters for
waters and suitable remediation methods are identified. A high amount of nitrates, sulphates, BOD and a low value of Dissolved Oxygen were observed during all three months of study
period and recommended various treatment methods for better and effective utilization of water
Exploration of Groundwater Quality to Promote Sustainable Environment
No full textGroundwater is the combination of different minerals and salts which is available to the human kind for the survival primarily and also for all the developmental activities of
the society. Around the world the quality of the groundwater at
majority of the fresh water aquifers is good and recommendable
for consumption with basic treatment where as the accessibility of groundwater[6] depends on the practices taking place for lifting of water, rate of consumption along with the climatic conditions. Groundwater is the most important and the essential need for all the living beings irrespective of age and the species they belongs to, because almost more than ninety percent of metabolic activities of the human beings and the other living organisms depends on the water itself, even though water is available in the other notable form as surface water [5] it is not at all recommendable for consumption without proper required treatment [7]. In the present scenario accessing of quality groundwater is the most difficult and complex issue to meet the daily demand of the public especially in the developing cities [9] and the towns it is very big complicated issue due to the continues addition of unpredictable population year by year which makes the situation more worse. Apart from the above man made activities quality and the quantity of groundwater also depends on the existed soil conditions and its function with respect to the water holding capacity and rate of infiltration. The present study was carried out at downstream area of Krishna River in mangalagiri mandal of Guntur district, Andhra Pradesh. The study area had been divided into eight locations based on the possible interference of groundwater by human activities to find out the complete and detail composition of various cationic, anionic and heavy metals of water to estimate the suitability of water for consumptio