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The effects of acid hydrolysis parameters (acid type, acid concentration, reaction time, and temperature) on the properties of nanocellulose (NC) extracted from almond shells were investigated. The highest percentage yield of NC obtained from each type of acid was 71.8% using 25% w/v sulfuric acid at 50°C for 60 min, followed by 71.1% with 50% w/v perchloric acid at 35°C for 15 min, and finally 67% with 50% w/v methane sulfonic acid at 25°C for 10 min. The hydrolysis treatment using sulfuric and perchloric acids greatly affect the NC particle size and length. The extracted NCs show different thermal degradation profiles due to the difference in the crystallinity index and types of acid used. Hydrolysis with strong acids (sulfuric and perchloric acids) produce NC with lower crystallinity due to the degradation of both amorphous and crystalline regions in the cellulose. Furthermore, BET analysis revealed the NCs from the hydrolysis using sulfuric acid possesses the highest surface area, desorption/adsorption pore diameter, desorption, and adsorption cumulative pore volume compared to other acids.

The recycling of sodium borohydride poses a huge challenge to the drive towards a hydrogen economy. Currently, mechano-chemical, thermo-chemical and electrochemical are the only reported methods of recycling sodium metaborate into sodium borohydride. Much attention has been devoted to the mechano-chemical and thermo-chemical methods of reduction, but little focus has been devoted to electrochemical methods. This review describes the electrochemical behaviour of borohydride (BH4−) and metaborate (BO2−) anions in alkaline solutions. The BH4− is stabilized in highly concentrated alkaline solutions, while the electro-oxidation of BH4− is dependent on the type of electrode material. The attempts to electro-reduce the BO2− into BH4− is reviewed and the challenges, suggestions and future outlook of electro-reduction for the recycling of BO2− into BH4− is highlighted.

BACKGROUND: The prevalence of self-medication is high in Bangladesh due to easy access and poor regulatory controls over these drugs. Our study aimed to assess the attitude of university students in Bangladesh toward antibiotic usage, especially their knowledge and awareness about antibiotics and their resistance. We also evaluated the determinants behind their attempts at drug intake without prescription. MATERIALS AND METHODS: A cross-sectional study was conducted in Mawlana Bhashani Science and Technology University that included information from randomly selected 200 students from 15 departments using a structured questionnaire. The statistical analyses were performed by using SPSS software (version 21) and R programming. RESULTS: The study revealed that 61.0% of the students use self-medication at different times or always; 32.5% of the respondents keep antibiotics for future use, and 38% of the students think it is right to stop antibiotics when symptoms are improving. Half of the participants (47.5%) use antibiotics based on their previous experience. The criteria of antibiotic selection have a significant relationship with knowledge about antibiotic resistance (P = 0.017) and altered prescribed medicine without doctor's advice (P < 0.001). The multivariate analysis indicates that respondents who know about antibiotic resistance select antibiotics from the community pharmacists with respect to their own experience 5.102 times higher than those who do not know about antibiotic resistance. CONCLUSIONS: The study mainly explored the knowledge gaps of the students on the options that are responsible for antibiotic resistance in the community and found that students have mid-level knowledge (66%) about antibiotic resistance.