SEPARATION AND IDENTIFICATIONOF NORMAL HYDROCARBON, NONADECANE IN THE CABBAGE VEGETABLES SAMPLES (Brassica o/eracea VAR. CAPITATA F. ALBA) BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY

ABSTRACT Toxic normal hydrocarbon (NH), nonadecane in the methanolic extract of the whole of cabbage samples collected from different districts of Bangladeshwas analyzed by GC-MS. It was observed that NH deposition on the samples takes place in different morphological parts of the biological materials. The NH, nonadecane, was found in the cabbage samples collected from the highway road side by the extraction of methanol. The identification and quantification of the title compounds have not been reported previously in the cabbage sample. Keywords: Cabbagebrassica oleracea var. capitata f. albaquantificationnormal hydrocarbon, nonadecane, GCMS

Growth and yield of recently release wheat varieties under raised bed system in drought prone areas

In Bangladesh, the cereal, pulse and other crops have traditionally been planted after 3-4 ploughing operations followed by laddering which is slow, laborious, time consuming and also costly (Singh et al. 2003 and Timsina et al. 2001). Added to this is the increasing labor shortage especially in the peak period. Raised bed planting reduce production cost, save labor and water increases input efficiency, increases yields (Witt et al.2000). This experiment was undertaken to select the best genotypes bed planting and to determine their growth characteristics under this system

Drinking water insecurity in Southwest Coastal Bangladesh : how far to SDG 6.1?

Substantial progress has been seen in the drinking water supply as per the Millennium Development Goals (MDG), but achieving the Sustainable Development Goals (SDG), particularly SGD 6.1 regarding safely managed drinking water with much more stringent targets, is considered as a development challenge. The problem is more acute in low-income water-scarce hard-to-reach areas such as the southwest coastal region of Bangladesh, where complex hydrogeological conditions and adverse water quality contribute to a highly vulnerable and insecure water environment. Following the background, this study investigated the challenges and potential solutions to drinking water insecurity in a water-scarce area of southwest coastal Bangladesh using a mixed-methods approach. The findings revealed that water insecurity arises from unimproved, deteriorated, unaffordable, and unreliable sources that have significant time and distance burdens. High rates of technical dysfunction of the existing water infrastructure contribute to water insecurity as well. Consequently, safely managed water services are accessible to only 12% of the population, whereas 64% of the population does not have basic water. To reach the SDG 6.1 target, this underserved community needs well-functioning readily accessible water infrastructure with formal institutional arrangement rather than self-governance, which seems unsuccessful in this low-income context. This study will help the government and its development partners in implementing SDG action plans around investments to a reliable supply of safe water to the people living in water-scarce hard-to-reach coastal areas

Adoption of raised bed technologies with heat & drought tolerant wheat varieties in drought prone areas: A miracle success in Bangladesh

Tillage practices contribute greatly to the labor cost in any crop production system (Limon et al. 2006). Intensive tillage systems result in increased soil compaction and decreased soil organic matter (Singh et al. 2003) and biodiversity (RWC-CIMMYTet al. 2003). Reduced tillage practices, such as bed planting, can offset the production cost and other constraints associated with environment and socio-economic conditions. Raised bed planting of different crops helps achieve good plant establishment, save water, seed, production cost and increases input efficiency, and increases yields in rice-wheat systems (Sayre et al. 2000). The present study examined adoption of raised beds should be needed for farmer’s income and livelihood in drought prone areas

A Study on Industrial Waste Effluents and Their Management at Selected Food and Beverage Industries of Bangladesh

Various types of waste effluents produced by two industries were studied to verify their environmental effects and to prepare a suggestion for management of those wastes. Two types of wastes were considered- wastewater and solid wastes. Analysis on three samples of wastewater was performed to determine the physical, chemical, organic and biological pollution. The pH values were 6.58, 6.75 & 6.64; amount of TDS were 235, 241 & 270 ppm; total hardness were 126, 123 & 144 ppm; calcium hardness were 105, 99 & 122 ppm, all the values of P-alkalinity were zero and values of M-alkalinity were 40, 40 & 45 mg/l. Iron concentrations were 0.21, 0.18 & 0.19 mg/l. Their Cl2 test proved absence of Cl2 Molecule. Only one sample was analyzed for bacterial viable count (44x105 cfu/ml), fungal test (fungi were absent), DO (6.8 mg/l), BOD (156 mg/1) and COD (267 mg/1). Results suggested that iron concentrations, pH values, TDS and DO were within the standard range. Level of total hardness, alkalinity, BOD, COD and total bacterial count exceeded level of standards. Their effects were evaluated from secondary data sources. Solid waste quality and the current onsite waste management facilities were studied through questionnaire survey and direct observations. Most of the cases, current waste management systems were old fashioned and indigenous. After studying literature on waste management procedures, a waste management plan for these industries has been prepared. Study results show that, these selected industries do produce few waste linked problems which can be minimized following some strict management measures

Modification and Characterization of Biodegradable Chitosan/ Starch-Based Films with Monomer 1,4-Butanediol Diacrylate (BDDA) by Gamma Radiation

Chitosan reinforced starch-based biodegradable films were prepared by solution casting. Tensile strength (TS), tensile modulus (TM), elongation at break (%), and water vapor permeability (WVP) of the 50% chitosan containing starch-based films were found to be 47 MPa, 550 MPa, 16%, and 2.45 g·mm/m2·day·kPa, respectively.Monomer 1,4 butanediol diacrylate (BDDA) was added (0.25-1% by wt) to the starch/chitosan (50:50) based film formulation. Then, films were cast and gamma irradiated from a radiation dose varied from 1 kGy to 25 kGy. Then mechanical and barrier properties were evaluated. The highest TS (80 MPa) and TM (880 MPa) of the films were found by using 0.5% monomer at 5 kGy dose. The WVP of the films were found to be 1.50 g·mm/m2·day·kPa which is 38.77% lower than control starch/chitosan-based films. Molecular interactions due to incorporation of BDDA were supported by Fourier transform infra red (FTIR) spectroscopy. The water uptake of the films pointed out better hydrophobic character due to incorporation of BDDA in starch/chitosan-based films. Surface morphologies of BDDA treated films were examined by scanning electron microscope (SEM) and suggested better morphologies due to BDDA treatment with starch/chitosan-based biodegradable films

Modal interaction of power systems with high penetration of renewable energy and BES systems

A B S T R A C T Integration of renewable energy sources (RESs) at transmission level is getting popular in the recent years. RESs have advantages of generating clean and environmentally friendly electricity. However, due to the uncertainty and less inertia characteristic of the RESs based power plant, it can bring negative impacts on small signal stability which is also known as low-frequency oscillatory stability. Hence, utilizing an additional device, such as battery energy storage (BES) in power system with high penetration of RESs is inevitable. BES system could provide additional active power to the grid to overcome the shortfall energy from RESs. Conversely, BES installation may also introduce negative impact on system dynamic in terms of possible interaction with other elements of the power system. Therefore, proper gain control setting of BES is required to avoid undesirable interaction and make sure system stability. This paper investigates the impact of gain variation in BES controller to oscillatory stability and modal interaction on the power system. Eigenvalue trajectories, participation factor and time domain simulation of the critical modes are thoroughly investigated. Influence of the capacity of BES and its location on damping ratio of weak modes is also examined in the paper. Moreover, the mitigation of modal interaction occurrence through BES gain tuning using metaheuristic algorithms is proposed in this paper. From the simulation results, it was found that increasing BES’s gain controller could lead to the interaction events. It was also reported that the proposed tuning method is feasible to mitigate the occurrence of modal interaction Keywords: Modal interaction Low-frequency oscillation RESs BES syste

Coverage Analysis of mmWave and THz-Enabled Aerial and Terrestrial Heterogeneous Networks

Heterogeneous networks (HetNets) are becoming a promising solution for future wireless systems to satisfy the high data rate requirements. This paper introduces a stochastic geometry framework for the analysis of the downlink coverage probability in a multi-tier HetNet consisting of a macro-base station (MBS) operating at sub-6 GHz, millimeter wave (mmWave)-enabled unmanned aerial vehicles (UAVs) operating at 28 GHz, and small BSs operating both at mmWave and THz frequencies. The analytical expressions for the coverage probability for each tier have been derived in the paper. Monte Carlo simulations are then performed to validate the analytical expressions. The effectiveness of the HetNet is analyzed on various performance metrics including association and coverage probabilities for different network parameters. We show that the mmWave and THz-enabled cells provide significant improvement in the achievable data rates because of their high available bandwidths, however, they have a degrading effect on the coverage probability due to their high propagation losses