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Ikram Adeel,Raza Ahmad,정현 대한용접접합학회 2020 대한용접·접합학회지 Vol.38 No.3
This study was performed to investigate the AC-GMAW process for joining of 6 mm to 8 mm thick AH36 steel plates in a single pass welding using a square groove butt joint configuration. A broad range of experiments was conducted at different welding speeds and joint gaps. Initially, a suitable setting of welding speed and the joint gap was determined based on the results of penetration depth and the gap bridging ability of the welded joints. Then, the quality of the selected welded joints was examined by hardness and tensile testing. Microstructure and fractured sur�face analysis were carried out using scanning electron microscopy (SEM) to examine the surface morphology. Based on the experimental findings, recommendations were made for selecting suitable input welding parameters for the welding of plates up to 8 mm using the AC-GMAW process.
Biomass Based Bioenergy: Technologies and Impact on Environmental Sustainability
Ikram Mehrez,Sutha Shobana,Georgeio Semaan,김상현,Gopalakrishnan Kumar 대한환경공학회 2022 대한환경공학회지 Vol.44 No.1
Biomass based bioenergy has many advantages evidently as their available quantity and renewability, when compared to the petro-derived traditional fossil fuels. Thereby, such bioenergy occupies a vital role defensively to the global energy requirement as well as guarantee energy supply. On the other hand, it should be considered that the development of biomass based energy may lead to some serious environmental issues and those are only based on the published data. Such adverse environmental alterations, mainly erosion of soil organic carbon, greenhouse gas emissions, lessening of water quantity and quality, have mainly been based on type of biomass source utilized, location of the land, and management practices. Consequently, more attention should be paid towards environmental protection, while implementing the production of biomass based bioenergy. In this study, various types of biomass, its conversion technology, advantages and disadvantages and its environmental issues of bioenergy production in terms of adverse impact on water, air and soil along with protection measures have been discussed.
Ikram Adeel,정현 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.3
A numerical model of the metal transfer process was developed using the thermomagnetohydrodynamic equations and the phase-field method to investigate the influence of pulse frequency on the metal transfer mode, dynamics, and thermal behavior in the pulsed wire-arc additive manufacturing (WAAM) process. The control of droplet transfer mode, dynamics, and thermal behavior is essential in WAAM; otherwise, several potential defects such as high residual stresses and distortion, poor dimensional accuracy, and surface quality may occur due to uneven heat input condition and process instability. Therefore, in this study, eight sets of pulse frequencies ranging from 50 to 225 Hz, in steps of 25 Hz, using identical power source parameters, such as pulse duty cycle and average current of 25.4% and 152 A, respectively, were considered and compared for a nearly square current waveform. The results reveal that only the current pulses with a medium frequency regime (100–175 Hz) achieve the one-droplet-per-pulse mode of metal transfer. Moreover, an increase in pulse frequency leads to a shorter necking length of the pendent droplet and a significantly lower average speed and temperature of the detached droplet. The results for the heat flux analysis indicate that Joule heating and arc heating decrease due to the increase in pulse frequency, whereas the sheath heating remains almost constant using different pulse frequencies. The proposed numerical scheme provides a detailed understanding of controlling and tailoring the different metal transfer modes and their metal transfer stability during WAAM, which benefits further process optimization and control.
Ikram, Muhammad Maulana Malikul,Esyanti, Rizkita Rachmi,Dwivany, Fenny Martha The Korean Society of Plant Biotechnology 2017 식물생명공학회지 Vol.44 No.3
Photoperiod is one of the factors affecting productivity of cucumber plant by inducing ethylene hormone production and so triggering flower sex differentiation into female flower. However, only few studies have been perfomed in order to reveal the effect of photoperiod in molecular level in relation to the flower differentiation. Therefore, in this study, Mercy cultivar of cucumber (andromonoecious) was treated with photoperiod of 8, 12, 16 hours of light, while control received no treatment of additional light. Photoperiod of 8 hours was achieved by blocking the sunlight with shade net and 16 hours by giving longer light exposure using white LEDs. Cucumber's flowers were quantified and the apical and lateral shoots were extracted to evaluate the gene profile related to the photoperiod, ethylene production, and female flower differentiation, which were CsACS2, CsETR1, CsCaN, and CsPIF4 using PCR method. Photoperiod of 8 hours affected the production of female flower with average number of 6.7 flowers in main stem and 8.0 flowers in lateral stem, compared to photoperiod of 12 and 16 hours which produced 3.7 and 2.0 flowers in main stem with 7.0 and 11.3 in lateral stem, respectively. In silico studies in this experiment resulted in proposed model of signal transduction that showed the connection between ethylene production and flower differentiation. PCR analysis confirmed the expression of CsACS2, CsETR1, and CsCaN, that was positively correlated with numbers of female flowers in cucumber, but the expression of CsPIF4 that represent photoperiod haven't been confirmed correlated with the ethylene production and flower differentiation.
Ikram, Hira,Khan, Hamid Ali,Ali, Hina,Liu, Yanhui,Kiran, Jawairia,Ullah, Amin,Ahmad, Yaseen,Sardar, Sadia,Gul, Alia The Korean Society for Microbiology and Biotechnol 2022 한국미생물·생명공학회지 Vol.50 No.2
Cellulases are a group of biocatalyst enzymes that are capable of degrading cellulosic biomass present in the natural environment and produced by a large number of microorganisms, including bacteria and fungi, etc. In the current study, we isolated, screened and characterized cellulase-producing bacteria from soil. Three cellulose-degrading species were isolated based on clear zone using Congo red stain on carboxymethyl cellulose (CMC) agar plates. These bacterial isolates, named as HB2, HS5 and HS9, were subsequently characterized by morphological and biochemical tests as well as 16S rRNA gene sequencing. Based on 16S rRNA analysis, the bacterial isolates were identified as Bacillus cerus, Bacillus subtilis and Bacillus stratosphericus. Moreover, for maximum cellulase production, different growth parameters were optimized. Maximum optical density for growth was also noted at pH 7.0 for 48 h for all three isolates. Optical density was high for all three isolates using meat extract as a nitrogen source for 48 h. The pH profile of all three strains was quite similar but the maximum enzyme activity was observed at pH 7.0. Maximum cellulase production by all three bacterial isolates was noted when using lactose as a carbon rather than nitrogen and peptone. Further studies are needed for identification of new isolates in this region having maximum cellulolytic activity. Our findings indicate that this enzyme has various potential industrial applications.
Analysis of Policy for Independent Grocery Stores in Morocco
Ikram-Benchrif,Young-Ho Nam,Kyoung-Ae Kim 한국무역연구원 2017 무역연구 Vol.13 No.5
The objective of this study is to identify the main issues that limited the success of the government plan to modernize traditional retail in Morocco. To achieve the objective, a sample of 80 owners of independent grocery stores was used. The SPSS statistical software was used to analyze data and identify major issues. According to results of the study, the government plan’s limited success is resulted from implemented strategies that did not match the socio-cultural reality and did not meet the present needs of independent grocery stores owners. And owners of independent groceries did not understand all the benefit of being part of a franchise system. On the contrary, many owners view the franchise system as a form of exploitation by the franchisor that would hurt their independence and autonomy. To remedy this situation, the study suggests establishing cooperatives and associations of small grocery stores as an optimal channel through which the government could restructure and modernize this sector in Morocco. Synergy and dynamics should be created between independent store owners, associations and the government to provide optimal support.