Groundwater quality deterioration due to anthropogenic natural activities and its immense utilization in various sectors is considered a great concern. The aim of this study is to determine the groundwater quality parameters at various sources in and around Dhaka city and compare them with Bangladesh drinking water standards. In this study, six groundwater quality parameters (pH, DO, COD, TS, TDS, and arsenic) and ten groundwater samples are analyzed to determine the water quality. The collected samples have maximum and minimum pH values of 6.9 and 6.4, respectively. Maximum and minimum DO values are 0.3 and 0.1 mg/L, respectively. The arsenic concentration is 0 mg/L for all collected groundwater samples. The maximum and minimum COD values are 0.3 and 0.1 mg/L, respectively. The maximum and minimum TS values are 4 and 1 mg/L, respectively. The obtained values are then compared with the Bangladesh drinking water quality standards. Finally, the water quality index (WQI) values are calculated to determine the suitable uses of groundwater in and around Dhaka city. Based on WQI values, the groundwater quality is excellent in the study area.
Abstract: Two different shapes of offset optical fiber was studied based on coreless fiber for refractive index (RI)/concentration (con.) measurement, and compare them. These shapes are U and S-shapes, both shapes structures were formed by one segment of coreless fiber (CF) was joined between two single mode (SMF) lead in /lead out with the same displacement (12.268µm) at both sides, the results shows the high sensitive was achieved in a novel S-shape equal 98.768nm/RIU, to our knowledge, no one has ever mentioned or experienced it, it’s the best shape rather than the U-shape which equal 85.628nm/RIU. In this research, it was proved that the offset form has a significant effect on the sensitivity of the sensor. Addi
... Show MorePlatelet‐rich fibrin (PRF) has been widely used in regenerative dentistry due to many growth factors produced. Periostin, a matricellular protein, is a reliable marker for tissue regeneration. Periostin is part of the cellular matrix and regulates bone homeostasis. This study aims to explore the efficacy of PRF in improvement of the clinical periodontal parameters as an adjunct to the scaling and root planing and to evaluate periostin level in gingival crevicular fluid (GCF) at baseline, 1‐ and 3‐month recall visits. Fourteen periodontitis patients who met the inclusion criteria were recruited in this study. Two contralateral periodontal pockets with 4–6 mm in depth in each patient were sel
Topological indices provide important insights into the structural characteristics of molecular graphs. The present investigation proposes and explores a creative graph on a finite group G, which is known as the RIG. This graph is designated as ΓRS G2(4) indicating a simple undirected graph containing elements of G. Two distinct ertices are regarded as nearly the same if and only if their sum yields a non-trivial involution element in G. RIGs have been discovered in various finite groups. We examine several facets of the RIG by altering the graph through the conjugacy classes of G. Furthermore, we investigate the topological indices as applications in graph theory applying the distance matrix of the G2(4) group.
Abstract
Friction stir welding is a relatively new joining process, which involves the joining of metals without fusion or filler materials. In this study, the effect of welding parameters on the mechanical properties of aluminum alloys AA2024-T351 joints produced by FSW was investigated.
Different ranges of welding parameters, as input factors, such as welding speed (6 - 34 mm/min) and rotational speed (725 - 1235 rpm) were used to obtain their influences on the main responses, in terms of elongation, tensile strength, and maximum bending force. Experimental measurements of main responses were taken and analyzed using DESIGN EXPERT 8 experimental design software which was used to develop t
... Show MoreThe activation energy and optical band gap of different regions (p-type) polysilicon have been measured. Both microscopic studies and current-voltage characteristics of diodes prepared on different surface regions were carried out. Comparison of diodes parameters and microscopic studies indicate that the type of angles between boundaries has a significant effect on diodes parameters while the boundary lengths per unit area has less effect. The mechanism of Al-interaction with grain boundaries and their intersecting points at different temperature were also studies. The X-ray fluorescence spectrometry has been used for detection of diffused A1%.
Milling Machining is a widely accepted nontraditional machining technique used to produce parts with complex shapes and configurations. The material is removed in two stages roughing and finishing, the flat end cutter removed the unwanted part of material, then finished by end mill cutter. In milling technique, the role of machining factors such as cutting depth, spindle speed and feed has been studied using Taguchi technique to find its effectiveness on surface roughness. Practical procedure is done by Taguchi Standard matrix. CNC milling is the most conventional process which is used for removing of material from workpiece to perform the needed shapes. The results and relations indicate that the rate of feed is v
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