A Facile, Fast, and Low-Cost Method for Fabrication of Micro/Nano-Textured Superhydrophobic Surfaces

Background Alkyl ketene dimer (AKD) is frequently used in paper industry as an inexpensive sizing agent. The formation of a fractal structure after curing the solidified AKD for an extra-long time (4 - 6 days) results in superhydrophobicity. In this study, a facile and low-cost method was utilized to turn AKD’s surface superhydrophobic in a very short period of time. Method We fabricated a superhydrophobic layer by dipping glass and paper substrates in molten AKD and then treating them with ethanol after solidification. The samples were characterized by X-ray diffraction, Scanning electron microscopy, Fourier transform-infrared spectroscopy, X-ray photoelectron spectroscopy, Confocal laser scanning microscopy, and dynamic contact angle goniometry. Results The results show that briefly treating the coatings, obtained from isothermally heated AKD melt at 40°C for 3 min, with ethanol leads to superhydrophobicity with an advancing and receding contact angle of 158.7±1.4° and 156.8±0.9°, respectively. By increasing the melt temperature to 70°C and heating time to 6 h followed by ethanol treatment, the advancing and receding contact angles increased to 163.7±1.3° and 162.6±1.2°, respectively. Conclusions This enhancement in superhydrophobicity is due to the formation of entangled irregular micro/nano textures that create air cushions on the surface resulting in droplet state transition from Wenzel to Cassie. In this method, ethanol can be used several times, and the energy consumption becomes very low. Based on the other techniques in this field, our method has eliminated the complex equipment and procedure applied in the fabrication of a superhydrophobic AKD.https://scholarscompass.vcu.edu/gradposters/1072/thumbnail.jp

Mental Health Issues in the COVID-19 Pandemic and Responses in Bangladesh : View Point of Media Reporting

Background: The negative impact of COVID-19 on mental health has been reported by media throughout the world, although this role is not well-understood in low-and middle income countries (LMIC). We examined the reporting of mental health issues during the COVID-19 pandemic in Bangladesh and initiatives undertaken to support mental health reported from the viewpoint of media. Methods: We reviewed articles published in 10 local newspapers, including seven Bangla and three English newspapers, during the first year of the COVID-19 pandemic. News topics were identified through discussions among the team members, with searches across online newspapers and portals. Data extrapolated from newspapers were documented in an Excel spreadsheet. A mixed-method approach was used following a framework analysis for analyzing data. Recurring issues and commonly emerging topics were generated from the data. Descriptive statistics were applied for analyzing quantitative data. Results: Between March 2020 and March 2021, we have identified 201 reports on mental health issues including 45 reports (22.4%) focused on stress due to the associated financial crisis, unemployment and loneliness, 50 reports (24.9%) of 80 apparent suicides linked to family issues, disharmony in conjugal relationships, harassment, sexual violence, emotional breakdown, financial crisis, and stigma due to COVID-19.There were 77 reports (38.3%) concerning domestic violence during the pandemic. Twenty-nine reports (14.4%) referenced actions taken by different organizations to address mental health issues in response to the pandemic in Bangladesh. Conclusion: News coverage has the scope to highlight important issues that can emerge as a consequence of the COVID-pandemic, such as mental health, in a low resource setting. Capacity building of the media on the way to report mental health issues during emergency situations could be a useful strategy for more credible reporting on mental health issues during the COVID-19 pandemic for raising awareness of the public and policymakers about the negative consequences on mental health of the COVID-19 pandemic in Bangladesh. Adopting policies to support essential mental health care and promoting the local organizations to take timely public health measures will be imperative for averting the negative consequences of mental health due to the COVID-19 pandemic in Bangladesh

Influence of Citric Acid and Hydrogen Peroxide on Postharvest Quality of Tuberose (Polianthes tuberosa L. ‘Pearl’) Cut Flowers

Quality of cut flowers is an important issue at postharvest as well as an important factor contributing to marketing of and profitability from the tuberose. In this study, the effects of citric acid (CA) and hydrogen peroxide (H2O2) added to the vase water on postharvest quality of tuberose cut flowers were investigated. CA was applied in concentrations of 50, 100, 200, 400 mg·dm−3 and H2O2 in concentrations of 10, 20, 40 and 80 mg·dm−3 and distilled water as control treatment. Results showed that both compounds had significant positive effects on solution uptake, wilting and abscission of florets, relative water content, chlorophyll content, and vase life duration. The effects of 100 and 200 mg·dm−3 of CA and 20 and 40 mg·dm−3 of H2O2 proved to be more effective than other treatments. Both compounds increased the vase life of tuberose cut flowers and CA at concentrations 100 and 200 mg dm−3 and H2O2 at concentrations 20 and 40 mg dm−3 doubled this time up to 14-17 days

Total phenolic content, antioxidant, and antibacterial activities of seed and pod of Prosopis farcta from Sistan region, Iran

In this study, antioxidant and antibacterial activities of Prosopis farcta (Fabaceae) were investigated. The extracts were derived from seed and fruit pod parts by Ethanol, Methanol, Octanol and n-heptan solvents. High performance liquid chromatography analysis was used to measure antioxidant activities. Among the extracts, the seed Octanol extract (IC50=0.95 µg/ml) showed the best antioxidant activity. Antioxidant activities in various solvents showed different trends that may be as a result of differences in polarity and H-bonding ability of each solvent. The highest phenolic content of P. farcta was also obtained by the Octanol extraction in both seed and pod organs. Antibacterial properties of extracts were only recorded by methanol and ethanol extracts of the fruit pods which inhibited the growth of Staphylococcus and Escherichia coli. The results of the present work indicated that the selective extraction of Prosopis farcta by appropriate solvents could be very important to obtain bioactive fractions

Reducing Nitrogen Loss By Application Of Natural Clinoptilolite Modified With Quaternary N-Alkyl Agent As Controlled-Release Fertilizer In Two Species Of Beans (P. Vulgaris And Vigna Unguiculata)

In this work, a novel controlled-release fertilizer (CRF) was designed by using new quaternary N-alkyl as an innovative surface modifier for clinoptilolite in order to adsorb the nitrate anion. So far, a few number of commercial cationic surfactants have been introduced for engineered zeolites to adsorb and slow release anions. Therefore, an organic ligand was synthesized for the first time and was applied for modification of clinoptilolite. Investigating the effect of pH and adsorbent dosage showed that the experimental adsorption data were fitted well with the Langmuir and Freundlich isotherm models. Moreover, nitrate leaching tests were performed and the results confirmed that nitrate concentration of the leachate from the soil amended with novel fertilizer was 42% lower than that of the urea fertilizer. The growth parameters including were studied and the results showed that the red beans planted in the soil amended with modified fertilizer had the best results

Design And Fabrication Of A High Performance Inorganic Tandem Solar Cell With 11.5% Conversion Efficiency

Tandem solar cell is a design that combines two types of solar cells to benefit their advantages. We show a new concept for achieving highly efficient dye sensitized and quantum dot tandem solar cells. The new tandem cell further enhances the performance of the device, leading to a power conversion efficiency more than 11% under 1.5 Air Mass. To the best of our knowledge, this is the first time that the efficiency over 11 percent is achieved based on tandem solar cell. X-ray diffraction, Transmission Electron Microscopy, Scanning Electron Microscopy, Current-Voltage measurments, Intensity modulated photocurrent spectroscopy, intensity modulated photovoltage spectroscopy, Energy Dispersive X-ray spectroscopy, Brunauer-Emmett-Teller, Barrett-Joyner-Halenda and absorption spectroscopy were used to characterize the fabricated solar cells

Multifarious indigenous diazotrophic rhizobacteria of rice (Oryza sativa L.) Rhizosphere and their effect on plant growth promotion

A diverse group of rhizobacteria persists in the rhizospheric soil, on the surface of roots, or in association with rice plants. These bacteria colonize plant root systems, enhance plant growth and crop yield. Indigenous rhizobacteria are known to promote soil health, grain production quality and serve as sustainable bioinoculant. The present study was aimed to isolate, identify and characterize indigenous plant growth promoting (PGP) diazotrophic bacteria associated with the rhizosphere of rice fields from different areas of Jammu and Kashmir, India. A total of 15 bacteria were isolated and evaluated for various PGP traits, antagonistic activity against phytopathogens, production of hydrolytic enzymes and biofilm formation under in-vitro conditions. The majority of the isolated bacteria were Gram-negative. Out of 15 bacterial isolates, nine isolates produced IAA (12.24 ± 2.86 to 250.3 ± 1.15 μg/ml), 6 isolates exhibited phosphate solubilization activity (36.69 ± 1.63 to 312.4 ± 1.15 μg/ml), 7 isolates exhibited rock phosphate solubilization while 5 isolates solubilized zinc (10–18 mm), 7 isolates showed siderophore production, 8 isolates exhibited HCN production, 6 isolates exhibited aminocyclopropane-1-carboxylate (ACC) deaminase activity, 13 isolates exhibited cellulase activity, nine isolates exhibited amylase and lipase activity and six isolates exhibited chitinase activity. In addition, 5 isolates showed amplification with the nifH gene and showed a significant amount of nitrogenase activity in a range of 0.127–4.39 μmol C2H4/mg protein/h. Five isolates viz., IHK-1, IHK-3, IHK-13, IHK-15 and IHK-25 exhibited most PGP attributes and successfully limited the mycelial growth of Rhizoctonia solani and Fusarium oxysporum in-vitro. All the five bacterial isolates were identified based on morphological, biochemical and 16S rDNA gene sequencing study, as Stenotrophomonas maltophilia, Enterobacter sp., Bacillus sp., Ochrobactrum haematophilum and Pseudomonas aeruginosa. Rice plants developed from seeds inoculated with these PGP strains individually had considerably higher germination percentage, seed vigor index and total dry biomass when compared to control. These findings strongly imply that the PGP diazotrophic bacteria identified in this work could be employed as plant growth stimulators in rice