Origin and Accumulation Mechanism of Gas Condensate in Kailashtila Gas Field, Sylhet Basin, Bangladesh

The Kailashtila gas field (KGF) is situated in the northeastern part of Sylhet basin, Bangladesh. This paperpresents chemical characteristics of extractable natural gas in drilled well KTL-2, in order to examine their potentialsource and maturity of organic matter, and hydrocarbon accumulation mechanism in the basin. The gas condensate inthe KTL-2 composed primarily of methane (85.81 wt.%), ethane (6.68 wt.%), propane (2.13 wt.%), and traces of higherhydrocarbons (i-butane, 0.69 wt.%; n-butane, 0.73 wt.%; i-pentane, 0.50 wt.%; n-pentane, 0.44 wt.%; hexane, 1.27wt.%; heptane, 0.99 wt.%; octane, 0.24 wt.%). Nitrogen and CO2 contents in the gas condensate are low (0.46 wt.%and 0.05 wt.%, respectively). Average dry coefficient (C1/C1–5) value in the gas condensate is 0.93 (0.91–0.95), whichreflects relatively mature hydrocarbon migrating from nearby deeply buried source rocks. The δ13C1 (–39 to –40‰) andC1/C(2+3) (19.77) variation diagram show that gas condensate in the KGF is mainly controlled by type III kerogen, andthe organic matter was thermally mature in nature. However, the relationships between stable isotope value of methane(δ13C1), ethane (δ13C2) and propane (δ13C3) indicate mainly thermogenic origin of the studied gas condensate, andminor input from mixed thermogenic and bacteriogenic processes

Effective Cross-linking Dyeing Method for Jute Fabric with Reactive Dyes

With a view to develop an effective dyeing method for jute fabric, jute fabric known as Carpet Backing Cloth (CBC), made from jute fiber, was first desized, scoured, and bleached with hydrogen peroxide. Simultaneous dyeing and finishing methods were carried out using various reactive dyes with some cross-linking agents like Fixapret CPN, Fixapret ECOs of BASF, and Indosol E-50 Powder (Sandoz) along with some catalysts (MgCl2, 6H2O) and softening agent. Three types of cross-linking methods such as dry, moist, and wet were employed. The cross-linking method was optimized by treatment of bleached CBC with different concentrations of cross-linking agents and catalysts applying pad-dry-cure method at different temperatures. Significant improvement was found in dye fixation rate, dye fastness (washing, rubbing, light and perspiration) properties, and tensile strength of cross-linked dyed jute fabric. Regarding all dyeing and physical properties, Indosol E-50 powder along with various reactive dyes achieved highly satisfactory results. Fixapret CPN may also be comparable to Indosol E-50 powder

Role of Accumulated Calcium in Alleviating Aluminum Injury in Wheat Plants

Aluminum (Al) sensitive wheat cultivar kalyansona was grown for 14 d in a range of Ca solution (125, 625, and 2500 μM) plus other nutrients without Al. At 14 d after Ca treatment, half of these plants were harvested (H1), and the rest of the plants were exposed to 100 μM Al for additional 6 d and harvested (H2). Severe Al injury was found only in the plants with the lowest supply of Ca before Al treatment. Aluminum concentration in the apoplastic fluid was very high at 125 μM Ca probably because the plasma membrane of some of the cells was destroyed due to the attack of 100 μM Al. Aluminum content in roots decreased with increasing supply of Ca before Al treatment. Calcium content decreased drastically at harvest (H2) in the plants with 100 μM Al. Under Al stress conditions, the plant responded to Al in different ways due to not only the different Ca supply but also the variation of Ca content in the plant tissues. Actually, the plants having the largest Ca content in the roots before Al treatment can receive less Al injury during Al treatment. To substantiate this idea, a companion study was conducted to investigate the effects of 2500 μM Ca supply during, before, and after 100 μM Al treatment on root growth. The results indicated clearly that exogenous Ca supply before Al treatment is able to alleviate Al injury but less effective than Ca supply during Al treatment

Study of relationship between age and body mass index on knee osteoarthritis in advanced aged females in a divisional city of Bangladesh

Background: Knee osteoarthritis is a notable issue in senior citizens and is a burning problem worldwide. There are so many risk factors related to knee osteoarthritis but women's sex, age, and obesity are significant. The aim and objective of this study were to estimate the prevalence of knee osteoarthritis among women in the age group of 46 to 65 years and the effect of age and body mass index (BMI) on knee osteoarthritis.Methods: Cross-sectional study was conducted at outpatient department (OPD) in Mymensingh Medical College Hospital, a tertiary level hospital, among females of Mymensingh, a divisional city of Bangladesh in the age group of 46 to 65 years. Purposive sampling technique used to select study subjects. A total of 100 females participated in this study in one month (July 2019-August 2019).Results: 100 participants were enlisted in the study, in the age group of 46 to 55 years 39 (39%) and 56 to 65 years 61 (61%). Total 65 (65%) participants were affected with knee osteoarthritis. Among them, 19 (29.2%) participants were in the age group of 46-55 years and 46 (70.8%) participants were in the age group of 55-65 years, thus in the advanced age group, knee osteoarthritis is remarkably more. Participants affected with knee osteoarthritis with BMI ≥25 were significantly more affected 45 (69.2%) compared with participants with normal BMI 20 (30.2%).Conclusions: Knee osteoarthritis is significantly associated with advanced age and obesity. Advanced age and overweight were strongly associated with osteoarthritis in our population. Therefore, weight reduction and preventive measures can decrease the burden and will help in minimizing morbidity associated with OA

Knowledge, attitudes, and fear of COVID-19 during the Rapid Rise Period in Bangladesh

The study aims to determine the level of Knowledge, Attitude, and Practice (KAP) related to COVID-19 preventive health habits and perception of fear towards COVID-19 in subjects living in Bangladesh. Design: Prospective, cross-sectional survey of (n = 2157) male and female subjects, 13–88 years of age, living in Bangladesh. Methods: Ethical approval and trial registration were obtained before the commencement of the study. Subjects who volunteered to participate and signed the informed consent were enrolled in the study and completed the structured questionnaire on KAP and Fear of COVID-19 scale (FCV-19S). Results: Twenty-eight percent (28.69%) of subjects reported one or more COVID-19 symptoms, and 21.4% of subjects reported one or more co-morbidities. Knowledge scores were slightly higher in males (8.75± 1.58) than females (8.66± 1.70). Knowledge was significantly correlated with age (p < .005), an education level (p < .001), attitude (p < .001), and urban location (p < .001). Knowledge scores showed an inverse correlation with fear scores (p < .001). Eighty-three percent (83.7%) of subjects with COVID-19 symptoms reported wearing a mask in public, and 75.4% of subjects reported staying away from crowded places. Subjects with one or more symptoms reported higher fear compared to subjects without (18.73± 4.6; 18.45± 5.1). Conclusion: Bangladeshis reported a high prevalence of self-isolation, positive preventive health behaviors related to COVID-19, and moderate to high fear levels. Higher knowledge and Practice were found in males, higher education levels, older age, and urban location. Fear of COVID-19 was more prevalent in female and elderly subjects. A positive attitude was reported for the majority of subjects, reflecting the belief that COVID-19 was controllable and containable

Monovalent salt and pH-induced gelation of oxidized cellulose nanofibrils and starch networks: Combining rheology and small-angle X-Ray scattering

Water quality parameters such as salt content and various pH environments can alter the stability of gels as well as their rheological properties. Here, we investigated the effect of various concentrations of NaCl and different pH environments on the rheological properties of TEMPO-oxidised cellulose nanofibril (OCNF) and starch-based hydrogels. Addition of NaCl caused an increased stiffness of the OCNF:starch (1:1 wt%) blend gels, where salt played an important role in reducing the repulsive OCNF fibrillar interactions. The rheological properties of these hydrogels were unchanged at pH 5.0 to 9.0. However, at lower pH (4.0), the stiffness and viscosity of the OCNF and OCNF:starch gels appeared to increase due to proton-induced fibrillar interactions. In contrast, at higher pH (11.5), syneresis was observed due to the formation of denser and aggregated gel networks. Interactions as well as aggregation behaviour of these hydrogels were explored via ζ-potential measurements. Furthermore, the nanostructure of the OCNF gels was probed using small-angle X-ray scattering (SAXS), where the SAXS patterns showed an increase of slope in the low-q region with increasing salt concentration arising from aggregation due to the screening of the surface charge of the fibrils

Assessment of Hydrocarbon Generation Potential of Permian Gondwana Coals, Bangladesh

This paper represents the geochemical characteristics of Gondwana coals from the Barapukuria coal mine, Bangladesh in order to investigate the potential for hydrocarbon generation. A total number of twenty three coal samples were analyzed Rock-Eval pyrolysis, CHNS elemental analyses, maceral analysis and vitrinite reflectance. The samples were collected from drill hole GDH-40 of the Barapukuria coal mine encountered within Gondwana succession of Permian age. The TOC contents of the coal samples range between ~50 and 76 wt.% and the organic matter consists predominantly of type III and type IV kerogen with respect to hydrocarbon generation. The GP, HI, PI and Tmax values range between 7 and 35 mg HC/g rock, 20 and 62 mg HC/g TOC, 0.02 and 0.04, and 430 and 437oC, respectively. The organic matter is mainly gas prone and thermally immature to early mature level. The potential coal bed methane (CBM) generation of the Barapukuria basin is estimated to be 11 Gm3. Thus, underground coal gasification (UCG) is helpful for better development of subsurface coals at the Barapukuria basin, Bangladesh

Coal Mine Accidents in Bangladesh: Its Causes and Remedial Measures

Barapukuria coal mine (BCM) is located at Dinajpur district, NW Bangladesh. Total area is about 6.68 km2 and coal was encountered at a depth ranging between 118 and 509 m. Six major coal seams (seam I to seam VI) were identified at BCM, of which, thickest one is the seam-VI (~36 m). The estimated coal reserves is about 390 million tons and of this, nearly 64 million tons of coal is extractable. The annual production of coal is about 1 million ton. In this study several parameters were used to explore minimization of accidents and improvement of coal production in BCM. Considering the geological, hydrological and other technical parameters, longwall mining method is applied for extraction of coal. Longwall retreating mining method is also applied for extraction of coal from single face with the operational area protected by self-advancing hydraulic powered roof support (HPRS) system. These supports are moved forward causing the roof behind them to form an extensive abandoned area named goaf, which may lead to collapse with air blast. Coal in BCM is extracted from seam VI, using a multislice Longwall top coal caving method. Average ventilated air composition is ~20.94% oxygen, ~79.00% nitrogen, ~0.04% carbon monoxide, and minor water steam with huge dust. Production of coal was completed from 12 Longwall faces of 1st slice from seam VI. During production period several accidents and troubles within BCM have occurred. Poisonous gases such as carbon monoxide were detected during/after development of 1110 Longwall face, which increases up to 6000 ppm, therefore, sealed-off the face with mining equipments. During the development of belt gate roadway of 1101 Longwall face, maximum temperature and humidity increases up to 37 oC and 100%, respectively. Miners of BCM experienced some difficulties to work in that adverse environment. Air return roadway temperature was always 40 to 41oC in 1101 Longwall face during production period, faces temperature 46oC, water flow 600 m3/hr and humidity 100%. Due to roof-fall, toxic gas and very high temperature and humidity in the face 1105 and 1108, some miners were highly injured and died. Therefore, taking necessary safety and risk measures during development of face and roadway in BCM, production will be sustained by controlling roof-fall. Strata pressure of every faces is monitor regularly through electromagnetic emission detector as well as changing sufficient ventilation system, accidents of BCM could be controlled. Adding earth filling materials (e.g. sand, silt etc.) in to the vacuum goaf area, air blast accident should be reduced and surface subsidence would also be controlled. Considering all the problems of 1st slice and initiating extra caution for face development accident in BCM may reduce in 2nd slice and overall production may be increased significantly