The layout design problem is a strategic issue and has a significant impact on the efficiency of a manufacturing system. Much of the existing layout design literature that uses a surrogate function for flow distance or for simplified objectives may be entrapped into local optimum; and subsequently lead to a poor layout design. The present study explores the use of appropriate line balancing to facilitate a good layout design. Construction of a quality garment requires a great deal of know-how, a lot of coordination and schedule management. Clothing manufacturing consists of a variety of product categories, materials and styling. Dealing with constantly changing styles and consumer demands is so difficult. Furthermore, to adapt automation for the clothing system is also so hard because, beside the complex structure also it is labour intensive. Overall, the important criteria in garment production is whether assembly work will be finished on time for delivery, how machines and employees are being utilized, whether any station in the assembly line is lagging behind the schedule and how the assembly line is doing overall. To achieve this approach, work-time study, assembly line balancing and simulation can be applied to apparel production line to find alternative solutions to increase the efficiency of the sewing line. In this paper we showed how a good layout can be designed and productivity can be increased by appropriate assembly line balancing.
Bangladesh’s coastal regions are rich in saline water resources. The majority of these resources are still not being used to their full potential. In the southern Bangladeshi region of Patuakhali, research was conducted to investigate the effects of mulching and drip irrigation on tomato yield, quality, and blossom-end rot (BER) at different soil salinity thresholds. There were four distinct treatments applied: T1= drip irrigation with polythene mulch, T2 = drip irrigation with straw mulch, T3 = drip irrigation without mulch, and T4 = standard procedure. While soil salinity was much greater in treatment T3 (1.19–8.42 dS/m) fallowed by T4 (1.23–8.63 dS/m), T1 treatments had the lowest level of salinity and the highest moisture retention during every development stage of the crops, ranging from 1.28–4.29 dS/m. Treatment T3 exhibited the highest soil salinity levels (ranging from 1.19 to 8.42 dS/m), followed by T4 with a range of 1.23 to 8.63 dS/m. In contrast, T1 treatments consistently maintained the lowest salinity levels (ranging from 1.28 to 4.29 dS/m) and the highest moisture retention throughout all stages of crop development. In terms of yield, drip irrigation with no mulch treatment (T3) provided the lowest output (13.37 t/ha), whereas polyethylene mulching treatment (T1) produced the maximum yield (46.04 t/ha). According to the study, conserving moisture in tomato fields and reducing soil salinity may both be achieved with drip irrigation combined with polythene mulch. The research suggests that employing drip irrigation in conjunction with polythene mulch could effectively preserve moisture in tomato fields and concurrently decrease soil salinity.
Electrochemical behavior of nickel chloride was investigated in aqueous and reverse micellar solutions of a cationic surfactant, cetyltrimethylammonium bromide (CTAB) on glassy carbon (GC) and copper electrodes by cyclic voltammetric measurements. The electrochemical reduction of nickel ion to metallic nickel has been found to occur with ease on a copper electrode in aqueous solution. Electrodeposition of nickel on a copper substrate was therefore performed from reverse micellar solutions of CTAB/1-butanol/water with different water content using coulometric method at a fixed potential below the reduction potential. Morphology and microstructure of the deposits were examined by scanning electron microscopy; while elemental characterization was carried out by energy dispersive X-ray spectroscopic method and X-ray diffraction technique. The variation in the composition of the reverse micellar solutions brings about changes in the size and distribution of reverse micelles as revealed by dynamic light scattering measurements and consequently influences the morphology of electrodeposited nickel. The mechanism of electrodepostion of nickel from reverse micellar solutions has been elucidated and the organized media have, for the first time, been established as a suitable one for electrodeposition of nickel with tunable microstructure and morphology through systematic variation of the composition of the reverse micellar solutions.
BACKGROUND AND AIM: An investigation was conducted to assess the particulate matter (PM) removal capacity of four common roadside trees (Ficus benghalensis, Ficus religiosa, Mangifera indica, and Polyalthia longifolia) grown at four locations in Dhaka, Bangladesh. METHODS: Gravimetric analyses were performed separately to quantify PM in three size fractions (0.2-2.5 µm, 2.5-10 µm, and 10-100 µm) deposited on surfaces and trapped in waxes. The particulate matter deposited on the leaves of the studied plants was also analyzed for cadmium (Cd), chromium (Cr), lead (Pb), and nickel (Ni) concentrations. RESULTS:Among the species studied, the deposited mass of PM was highest on Ficus benghalensis. The mean PM load on plant foliage was significantly greater in the polluted sites compared with the control site (p0.05). Most of the PM accumulated on plant foliage belonged to the large fraction size (10-100 µm). Species-wise significant differences were also found among the sites with respect to total PM, surface PM, and wax-embedded PM (p0.05). The amount of wax deposited on the leaves of plants grown in these sites also differed (p0.05). A positive correlation was found between wax-embedded PM of diameter 0.2-2.5 µm and the amount of waxes. Ficus benghalensis was found to be the most effective with respect to total PM accumulation. On the other hand, Mangifera indica was found to be the most effective accumulator of wax-related PM and seems to be the best species for traffic-related sites, where organic substances from vehicle exhausts are present in high concentrations. CONCLUSIONS:PM concentration was found to be significantly correlated to the concentrations of Cd and Pb meaning these two trace elements deposited simultaneously with the PM and originated from common anthropogenic sources. Total metal accumulation capacities of different plants were evaluated using the metal accumulation index (MAI) and Ficus benghalensis was found to have the highest MAI value (13.60). KEYWORDS: particulate matter, roadside species, trace element, metal accumulation index
Differential capacitances were measured at Hg/room-temperature ionic liquids (RTILs) interfaces as a function of potential with the aim of getting an insight of their interfacial structures. Capacitance−potential curve measured at Hg in 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4) resembles well the inner layer capacity at the Hg/aqueous solution interface containing nonspecifically adsorbing electrolyte. In both cases, the hump decreases with an increase in temperature which is discussed in the light of the previous theory. Both the alkyl group and the charged moiety of the cation of 1-alkyl-3-methylimidazolium based RTILs are found to interact concurrently with the Hg surface with the possible change of their orientation in response to the applied potential, and the appearance of a shallow minimum in the capacitance−potential curve related to potential of zero charge (PZC) depends on the extent of their interaction. PZC shifts to the negative direction of potential with increasing the chain length of alkyl residue of the cationic moiety because of the constraint in the orientational change needed for the interaction of positively charged imidazolium ring with Hg surface. Electrocapillary curves were also measured to determine the PZC. Throughout this study, a minimum of the capacitance−potential curve is designated as the PZC in agreement with the maximum of the corresponding electrocapillary curve. Different aspects of the capacitance−potential curves are interpreted satisfactorily on the basis of the hitherto proposed concept of electrical double layer structure.
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The stability of superoxide ion (O(2)(*-)) generated chemically by dissolving KO(2) in dried dimethyl sulfoxide solutions containing imidazolium cation [e.g., 1-ethyl-3-methylimidazolium (EMI(+)) and 1-n-butyl-2,3-dimethylimidazolium (BMMI(+))] based ionic liquids (ILs) was investigated with UV-visible spectroscopic, NMR, and voltammetric techniques and an ab initio molecular orbital calculation. UV-visible spectroscopic and cyclic voltammetric measurements reveal that the O(2)(*-) species reacts with BMMI(+) and EMI(+) cations of ILs to form hydrogen peroxide. The pseudo first order rate constant for the reaction of BMMI(+) and O(2)(*-) species was found to be about 2.5 x 10(-3) s(-1). With a molecular orbital calculation, the O(2)(*-) species is understood to attack the 2-position (C-2) of the imidazolium ring (i.e., BMMI(+)) to form an ion pair complex in which one oxygen atom is bounded to C-2 and the other to the hydrogen atom of -CH(3) group attached to C-2. Eventually, the ion pair complex of BMMI(+) cation and O(2)(*-) species undergoes a ring opening reaction as evidenced with (1)H NMR measurement.
