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Background: Tomato is one of the most important and popular vegetable crop grown mainly in dry seasons in Bangladesh. The southern part of the country is suffering from soil salinity problem due to tidal floods. The increasing salinity in the cultivatable land causes huge crop failure. A dozen of tomato varieties have been developed but they are not been tested for salinity tolerance. Therefore, this study was conducted to evaluate the tolerance level of tomato varieties against NaCl salinity stress at the vegetative stage. Methods: The study comprised of four levels of electrical conductivity (EC) based NaCl salinity viz., EC 2 (control), EC 4, EC 6 and EC8 mS/cm and eight varieties of tomato. The two-factor pot experiment was carried out in a randomized complete block design with four replications. NaCl salinity was imposed on the tomato plants through a hydroponic culture system and the effects of salinity on shoot-roots traits were measured. Result: Results showed that morphological traits of tomato plants varied significantly with the salinity levels and variety. It is also noticed that all the vegetative traits reduced as salt concentrations increased in the solution. In combined effects of variety and salinity levels, it was found that BARI Tomato-17 performed superior. It can be concluded that variety BARI Tomato-17 showed comparatively salt tolerant than the other varieties. [ABSTRACT FROM AUTHOR]

Sweet gourd (Cucurbita moschata Duch ex Poir) has a high production volume in Bangladesh and holds third rank next to eggplant and radish. Salinity affects almost all growth and physiological aspects of the plant development and eventually reduces yield. Identifying salt tolerance among genetic resources and breeding populations is a valuable study for solving salinity problems. This research aimed to find sweet gourd hybrids tolerant to salinity. Sixteen sweet gourd hybrids (F1) were used for testing salt stress tolerance levels. Salinity stress was induced in pot soil by adding NaCl solutions (4, 8, 12, 16, and control 0.35 dS m-1). The experiment was conducted from October 2019 to March 2020 in a randomized complete block design with three replications. The research was conducted at the Horticulture Research Centre, Bangladesh Agricultural Research Institute (BARI), Gazipur. The measurements included changes in gas exchange parameters against photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (E), quantum yield (Fv/Fm), and relative water content (RWC). Results showed that the gas exchange traits and RWC in all hybrids decreased under stress compared to the control. Photosynthetic parameters in sweet gourd hybrids responded susceptibly to salt stress, thus suppressing overall growth under salinity stress. The reduction of gaseous exchange traits and RWC were minimal in P11 × P12 and P6 × P14. The highest Fv/Fm and RWC occurred in P11 × P12 at 8 dS m-1 salinity stress. The highest Fv/Fm and RWC appeared in P6 × P14 and P11 × P12 hybrids at 12 and 16 dS m-1 salinity stress, so the hybrid P11 × P12 appeared salt tolerant. [ABSTRACT FROM AUTHOR]

Purpose: Web 2.0 is a collaborative web development platform that has had tremendous usage in building effective, interactive, and collaborative virtual societies at home and abroad. Multicultural study is another trend that has tremendous possibilities to help people in the fight against racism and enables them to become active members of a democratic society. Based on the advanced and interactive features, Web 2.0 technologies could be appropriate media to build many virtual collaborative societies among students in local and global classrooms. Students and teachers from any corner of the world would be able to participate in such virtual communities to practice effective multicultural skills with no or minimum cost. The purpose of this paper is to address these issues. Design/methodology/approach: This is a conceptual framework of a Web 2.0 model. This paper focuses the background of Web 2.0 technologies and multiculturalism and a feasibility study of using Web 2.0 technologies in the teaching and learning of multiculturalism, and depicts a conceptual framework involving use of a Web 2.0-based collaborative model for a multicultural classroom using one of the simple but powerful Web 2.0 tools, blogging technology. Findings: Web 2.0 technologies could be crucial tools for students, teachers, educators and social workers to build and participate in many virtual collaborative societies to practice effective skills of multiculturalism. Social implications: Participants from different corners of the world are able to participate in virtual communities simultaneously to practice effective multiculturalism. Originality/value: This is a newly developed model.

The effects of the position of the current probe on electrical measurements as well as those of typical materials on the current of a He plasma jet during the interaction of the plasma jet with surface materials were investigated using a dielectric barrier discharge reactor, in which the two electrodes were isolated from ambient air by electrical insulating oil. Here, we demonstrate accurate discharge power measurement obtained by positioning the current probe between the two electrodes rather than on the ground wire. The emission current of the plasma jet increased sharply upon the interaction with a ground-connected metal surface, because in this case, the surface functioned as a second ground electrode. Similarly, important is that the average velocity of a plasma bullet can be estimated from the phase shift of the current waveforms at different positions. The phase shift can be monitored by an oscilloscope using a cursor tool during the plasma discharge process. The average velocity of the plasma bullets in this paper ranged from 56 to 266 km/s. [ABSTRACT FROM AUTHOR]

Abstract The conditions for the deposition of stable superhydrophobic coatings on glass substrates using a dielectric barrier discharge plasma jet with tetramethylsilane (TMS) and 3-aminopropyl(diethoxy)methylsilane (APDMES) as precursors were investigated. The coatings, which were formed under different plasma conditions, were characterized by various methods including atomic force microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, static water contact angle (WCA) and sliding angle measurement, and a scratch test. The results presented that superhydrophobic and mechanically stable plasma coatings could be obtained by optimizing the treatment time, applied voltage, gas flow rate into the plasma chamber, and APDMES/TMS ratio. The results indicated that the use of TMS on its own as the coating precursor led to the formation of unstable coatings. However, the mechanical stability increased significantly when APDMES and TMS were used in combination. As a result, a durable coating layer with a WCA of 163° and sliding angle of 3° was achieved for an APDMES/TMS ratio of 1.7. Highlights • Superhydrophobic coatings using non-thermal atmospheric-pressure plasma jet. • Plasma copolymerization of tetramethylsilane and an aminosilane for stable coating. • Maximum water contact angle of 163° with a sliding angle of 3°. [ABSTRACT FROM AUTHOR]

The impact of chemical farming and the negative consequences on the environment and human health in Bangladesh are on the rise. Organic farming is gaining attention and increasing globally because it is eco-friendly, safe and has benefits for human health. A field study was conducted at the horticulture farm of Bangladesh Agricultural University (BAU), My mensingh, to evaluate the growth and yield performance of cabbage cv. Atlas--70 using organic and inorganic fertilizers in various plant spacing arrangements. Two factor experiments were conducted on plant spacings of 60 cm x 40 cm (S1), 60 cm x 50 cm (S2) and 60 cm x 60 cm (S3) and fertilizers vermicompost (T1), biogen (T2), integrated plant nutrient system (IPNS) Organic (2/3) + inorganic (1/3) (T3) and inorganic (T4). IPNS (T3) application increased the marketable yield (54.77 t⋅ha-1) of cabbage. The highest marketable yield (48.75 t⋅ha-1) was obtained with a plant spacing of 60 cm x 40 cm (S1). No significant variation was found in plant spacings S1 and S2. The treatment combination of S2T3 recorded the highest plant height (37.81 cm), plant spread (47.75 cm), cabbage head (21.80 cm), stem length (12.31 cm), thickness of the cabbage head (12.53 cm) and marketable yield (65.0 t⋅ha-1). The results suggest that IPNS (T3) combining organic and inorganic fertilizer applications with a 60 cm x 50 cm spacing (S2T3) increases the yield performance of cabbage. [ABSTRACT FROM AUTHOR]

This work focused on the factors affecting the effective generation of corona discharge plasma in a honeycomb catalyst reactor. Pd, Co, and Ag were used as the active metal catalysts to investigate the plasma formation and decomposition of ethylene. Unlike the Ag-coated honeycomb catalyst, which resulted in excessive arcing, the Co-coated honeycomb monolith was able to generate stable plasma, but the discharge power was insufficient to decompose ethylene at an acceptable level. The incorporation of a small amount of Pd with Co significantly enhanced the discharge power and the ethylene removal performance. The catalytic activity of the prepared catalyst for the removal of ethylene was evaluated using plasma catalytic oxidation and thermal catalytic oxidation. ANOVA was used to assess the effect of single process factors and their relationships in the plasma process. All the process factors such as specific energy input (SEI), ethylene concentration, and flow rate were found to affect the ethylene conversion, CO 2 selectivity, and energy efficiency (EE). Under the optimal conditions, i.e., an SEI of 80 J/L, an ethylene concentration of 20 ppm, and a flow rate of 20 L/min, the ethylene conversion was 85 %, CO 2 selectivity was 70 %, and EE was 0.86 g/kW h. [Display omitted] • Stable corona plasma formation using Co/ZSM-5/monolith and Co-Pd/ZSM-5/monolith. • Bimetallic catalyst shows better catalytic activity than monometallic catalyst. • Ag/ZSM-5/monolith creates numerous arcing and poor plasma formations. • ANOVA with F-test investigates the relationship between the influential factors and NTP reaction activity. [ABSTRACT FROM AUTHOR]

Purpose – Web 2.0 is a collaborative web development platform that has had tremendous usage in building effective, interactive, and collaborative virtual societies at home and abroad. Multicultural study is another trend that has tremendous possibilities to help people in the fight against racism and enables them to become active members of a democratic society. Based on the advanced and interactive features, Web 2.0 technologies could be appropriate media to build many virtual collaborative societies among students in local and global classrooms. Students and teachers from any corner of the world would be able to participate in such virtual communities to practice effective multicultural skills with no or minimum cost. The purpose of this paper is to address these issues. Design/methodology/approach – This is a conceptual framework of a Web 2.0 model. This paper focuses the background of Web 2.0 technologies and multiculturalism and a feasibility study of using Web 2.0 technologies in the teaching and learning of multiculturalism, and depicts a conceptual framework involving use of a Web 2.0-based collaborative model for a multicultural classroom using one of the simple but powerful Web 2.0 tools, blogging technology. Findings – Web 2.0 technologies could be crucial tools for students, teachers, educators and social workers to build and participate in many virtual collaborative societies to practice effective skills of multiculturalism. Social implications – Participants from different corners of the world are able to participate in virtual communities simultaneously to practice effective multiculturalism. Originality/value – This is a newly developed model. [ABSTRACT FROM AUTHOR]

Nonthermal plasma combined with a practical-scale honeycomb catalyst of 5.0 cm in height and 9.3 cm in diameter was investigated for the removal of toluene. The creation of plasma in the honeycomb catalyst greatly depended on the humidity of the feed gas and the presence of metals on the honeycomb surface. Compared to the bare ceramic honeycomb, the metal-loaded one gave higher toluene removal efficiency because the decomposition of toluene by the plasma-generated reactive species occurred not only homogeneously in the gas phase but also heterogeneously on the catalyst surface. The present plasma-catalytic reactor was able to successfully remove about 80% of dilute toluene (15 ppm in air) at a large flow rate of 60 L/min with a specific energy input of 58 J/L. The honeycomb-based plasma-catalytic reactor system is promising for practical applications since it can overcome such problems as high-pressure drop and difficulty in scale-up encountered in packed-bed reactors. ga1 • The removal of toluene investigates on a practical-scale honeycomb catalyst. • A large flow rate without significant pressure drop is used to generate plasma. • Plasma intensity largely depends on the humidity of the feed gas. • The metal clusters dotted on the honeycomb surface can act as floating grounds. [ABSTRACT FROM AUTHOR]

The SrNiO3 perovskite catalyst was synthesized by the citrate sol-gel method and supported on γ-Al2O3 and Nickel foam, which was used to produce syngas (CO and H2) via dry reforming of propane (DRP). Several techniques characterized the physicochemical properties of the fresh and spent perovskite catalyst. The X-ray diffractograms (XRD) characterization confirmed the formation of the perovskite compound. Before the catalytic activity test, SrNiO3 perovskite catalyst was reduced in the H2 atmosphere. Results indicated that the H2 reduction slightly increased the activity of the SrNiO3 perovskite catalyst. The catalytic activity was examined for the CO2/C3H8 ratio of 3 and reaction temperatures in the range of 550 °C–700 °C. The results from the catalytic study achieved 88% conversion of C3H8 and 66% conversion of CO2 with SrNiO3/NiF at 700 °C. Also, syngas with a maximum concentration of 21 vol.% of CO and 29 vol.% of H2 was produced from the DRP. The strong basicity of SrNiO3 perovskite enhanced the CO selectivity, resulting in minimal carbon formation. Post reaction catalyst characterization showed the presence of carbon deposition which could have originated from propane decomposition. [ABSTRACT FROM AUTHOR]

Abstract Deposition of superhydrophobic coatings on glass substrates from hexamethyldisiloxane (HMDSO) precursor using an argon plasma jet at a relatively low power frequency (11.5 kHz) was studied. The coating hydrophobicity was first found to be strongly dependent on the gaseous shield. Nitrogen (N 2) rather than inert gases (argon, Ar, and helium, He) had an excellent shielding effect against the interference of ambient air on the plasma jet. The evolution of water contact angle (WCA) of the prepared coating was investigated upon the variations of the operating parameters, such as N 2 /Ar ratio, HMDSO concentration, deposition time and nozzle-to-substrate distance. Generally, the measured WCA gradually increased with increasing the values of these parameters and then leveled off at some specific values, except for the nozzle-to-substrate distance. The wettability of glass was completely switched from hydrophilicity to superhydrophobicity with the WCA reaching 168° and the sliding angle of about 3° at optimum conditions. The surface morphology analyses by scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that the prepared coating had a very high surface roughness and micro-nano structure, which intensely promoted the water repellence property. The chemical examination by X-ray photoelectron spectroscopy (XPS) clearly showed the shielding effect on the surface chemical composition of the coating. N 2 shield preserved a high carbon content (in CH 3 groups) from the precursor, while minimizing the incorporation of oxygen into the coating surface. Also, it was found that O (from O and OH radicals) has replaced C to form silica-like coating in case of without shielding gas or with Ar and He shields. Highlights • Superhydrophobic coatings using atmospheric pressure plasma jet • N 2 possessing an excellent shielding effect due to its high ionization potential • Plasma jet capable of producing micro-nano structured coatings [ABSTRACT FROM AUTHOR]

Cobalt oxide nanoparticles are widely used owing to their distinct properties such as their larger surface area, enhanced reactivity, and their superior optical, electronic, and magnetic properties when compared to their bulk counterpart. The nanoparticles are preferably synthesized using a bottom-up approach in liquid as it allows the particle size to be more precisely controlled. In this study, we employed microplasma to synthesize Co 3 O 4 nanoparticles because it eliminates harmful reducing agents and is efficient and cost-effective. Microplasma reactors are equipped with copper wire electrodes to generate plasma and are simple to configure. The product was characterized using UV-Vis spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The experimental parameters that were varied for the synthesis were: with or without stirring, with or without indirect ultrasonication, and with or without capping agents (urea and sucrose). The results showed that the microplasma enabled Co 3 O 4 nanoparticles to be successfully synthesized, with particle sizes of 10.9-17.7 nm, depending on the synthesis conditions., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)