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Introduction: Drug addiction is a burning problem in Bangladesh affecting vast population especially the youths. The spread of multi drug use has aggravated the overall situation affecting our personal, economical and social life, impairing health status, increasing crime and other unwanted risky behaviour. Objective: To find out the socio-economical status of drug addicted young population in Dhaka City. Materials and Methods: This descriptive cross sectional study was performed during August 2016 to December 2016 at five drug addiction treatment and rehabilitation centre in Dhaka. A total of 57 habitual drug addicted young people were selected by purposive and convenient method of sampling. The primary data was collected by repeated visit to centers and face to face interview with addicts and their family members using a pre tested semistructured questionnaire containing both closed and open ended query. Collected data were compiled and analyzed later on. Results: Most 45(78.95%) of the drug addicted young people were male and among them 12(21.05%) belonged to age group 15-17 years. Majority of addicts 46(80.71%) were Muslim. Educational qualification of 16(28.07%) samples was upto primary level, 21(36.84%) upto secondary level. Considering occupation, majority were students 14(24.56%) followed by unemployed 12(21.05%), day labourer 9(15.79%). Thirty five (61.40%) were the lone earning member of their family. Twelve people (21.05%) had monthly income of family below 10,000 taka. Most of the samples (64.91%) stayed in extended type of family. Thirty seven (75.51%) collected money for drug from family members and stealing from house followed by criminal activities 26(53.06%). Majority of the addicts (85.96%) started taking drugs after being influenced by friends. Causes of drug addiction included unemployment 12(21.05%), peer pressure 9(15.79%) and influence of foreign culture 8(14.03%). The commonly used drugs included- Barbiturate/sedatives 32(56.14%), Yaba 28(49.12%), Toluene/aica 22(38.59%). Oral route was the commonest 48(84.21%) followed by Injection 9(15.79%). Commonest place of drug addiction included dance bar/club house 18(31.58%), isolated room/mess 14(24.56%), open field 12(21.05%) and railway/ bus station 9(15.79%). Conclusion: The dangers of drug addiction have been shifted from upper to middle and lower middle class population of our country. Elaborate national plan is needed to motivate young generation for involvement in study and productive activities. Preventive measures for drug smuggling and addiction are needed to be taken with great caution. More drug addiction treatment and rehabilitation centres are required to combat present situation. Journal of Armed Forces Medical College Bangladesh Vol.12(2) 2016: 15-20

Oxidation of cyclohexane is an essential chemical reaction for the industrial manufacture of cyclohexanol and cyclohexanone. These two compounds, together known as ketone–alcohol (KA) oil, are the main feedstock for nylon 6 and nylon 6,6 productions. Several types of catalysts and reaction conditions have been used for cyclohexane oxidation. This paper presents a thorough literature review of catalytic materials used for cyclohexane oxidation to produce KA oil using oxygen, air and other oxidizing agents as well as utilizing different solvents. This review covers research and development reported over the years 2014–2020. This review aims to comprehend the type of catalysts, solvents, oxidants and other reaction parameters used for the oxidation of cyclohexane. Three types of cyclohexane oxidation processes namely thermocatalytic, photocatalytic and microwave-assisted catalytic have been reported. The results of the review showed that metal and metal oxide loaded silica catalysts performed excellently and provided high selectivity of KA oil and cyclohexane conversion. The use of peroxides is not feasible due to their high price compared to air and oxygen. Gold nanoparticles supported on silica performed with high selectivity and good conversion. The use of hydrochloric acid as an additive was found very effective to enhance the photocatalytic oxidation of cyclohexane. Water on the catalyst surface enhanced the reactivity of the photocatalysts since it helps in the generation of hydroxyl radicals.

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The catalytic activity of ZSM-5 zeolites with a SiO 2 /Al 2 O 3 molar ratio of 30, 50, 80, 280, and 410 was investigated in a fixed bed continuous flow reactor system and was found that the ZSM-5 zeolite with SiO 2 /Al 2 O 3 molar ratio of 280 (HZ-280) exhibited best catalyst performance. The optimized reaction conditions achieved were 500 °C, 1 bar pressure, and weight hourly space velocity of 15 h −1 using methanol as feed. At optimum reaction conditions, HZ-280 exhibited propylene selectivity of 47.3% and propylene yield 17.4% with 100% methanol conversion. HZ-280 zeolite was modified with P, Ce, Fe, and La to select the best promoter to enhance propylene selectivity and yield. The best-modified catalyst obtained was HZ-280 with 0.1 wt % phosphorus loading, which further improved propylene selectivity by 14% and yield by 24.7%. Then, the monolith structured catalysts were prepared by single-layer (6.8%), double-layer (10.3%), and triple-layer (13.1%) coating of HZ-280 catalyst. HZ-280 single-layer-coated monolith-structured catalyst effectively increased propylene selectivity by 19.2% and yield by 34.5% with no liquid hydrocarbons in the product. HZ-280-coated monolith catalyst was regenerated and was reused for three cycles. Negligible activity loss was observed for methanol conversion and propylene selectivity. This reflects that the structured catalyst is viable and economical for commercial applications. Analytical techniques such as X-ray diffraction, scanning electron microscopy−energy-dispersive X-ray, Brunauer−Emmett−Teller, and NH 3 -temperature-programmed desorption were used for characterization of the catalysts.