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In our study, the surface of bacterial cellulose was successively modified by copper and zinc oxide nanoparticles using direct current (DC) magnetron sputtering and radio frequency (RF) reactive sputter coating techniques. The target materials, copper and zinc, were 99.99% pure and used in the presence of argon (Ar) gas, while zinc nanoparticles were sputtered in the presence of oxygen gas to make zinc oxide nanoparticles. The as-prepared bacterial cellulose/copper/zinc oxide nanocomposite has good ultraviolet resistance, anti-static and antibacterial characteristics. The surface morphology and chemical composition of the nanocomposite were examined by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopic (EDS) techniques. The prepared bacterial cellulose/copper/zinc oxide nanocomposite illustrates excellent ultraviolet resistance (T.UVA%; 0.16 ± 0.02, T.UVB%; 0.07 ± 0.01, ultraviolet protection factor (UPF); 1850.33 ± 2.12), antistatic behavior (S.H.P; 51.50 ± 4.10, I.E. V; 349.33 ± 6.02) and antibacterial behavior (Escherichia coli; 98.45%, Staphylococcus aureus; 98.11%). Our nanocomposite prepared by sputter coating method could be a promising and effective candidate for ultraviolet resistance, antistatic and antibacterial in term of functional, technical, medical and in many daily life applications.Coatings 2020, 10, 364 2 of 17 extensive attention toward its use as a conductive material due to its low resistance characteristic in such applications. Cellulosic materials such as bacterial cellulose (BC) do not show any type of bactericidal property [16]. In order to acquire the bactericidal characteristic from bacterial cellulose, many scientists have worked on bacterial cellulose, that work encompassing several types of metals and metal oxide nanoparticles, among which Cu, CuO and ZnO conclusively exist [17,18]. Additionally, Zinc oxide has distinguished properties and has been considered for serval applications in terms of piezoelectric gadgets, semiconductors and sensors, and for antimicrobial functions [19,20]. Nowadays, researchers have more interest in using zinc oxide in the composition of nanoparticles with different approaches to regulate its structure and scope. Preparation of a nanocomposite with suitable base materials and zinc oxide nanoparticles could advance multifunctional materials, which exhibit a wide range of UV-resistance and antibacterial applications [21,22].Human beings, as well as other living organisms, are affected by ultraviolet radiation in this universe. A decrease in environmental pollution has gained more attention, but there still needs to be a type of composite which can resist ultraviolet radiation to save the lives of all creatures [23,24]. The main cause of skin cancer is ultraviolet radiation, which is a medium of free radicals. Moreover, it is a cause of environmental degradation; and damages various pigments and materials and degrades their physical characteristics [25]. The deposition of zinc oxide nanoparticles on sub...

Metallic superlattices of nickel and molybdenum have been synthesized for a wide range of layer thicknesses by alternate sputtering. X-ray examination shows that they are composed of layers of fcc nickel and bcc molybdenum oriented along [111]and [110]directions, respectively. Anomalies have been observed in the lattice spacings, elastic moduli, and electrical resistivity versus modulation wavelength. These anomalies occur simultaneously at the same superlattice wavelength. The anomalies have been interpreted as due to strains in the nickel lattice.

An outdoor soil burial test was carried out to evaluate the degradation of commercially available LDPE carrier bags in natural soil for up to 2 years. Biodegradability of low density polyethylene films in soil was monitored using both optical and scanning electron microscopy (SEM). After 7-9 months of soil exposure, microbial colonization was evident on the film surface. Exposed LDPE samples exhibit progressive changes towards degradation after 17-22 months. SEM images reveal signs of degradation such as exfoliation and formation of cracks on film leading to disintegration. The possible degradation mode and consequences on the use and disposal of LDPE films is discussed.

The River Buriganga is the life line of the Dhaka city and flanked in its southern side. The aerobic heterotrophic bacterial count of the River Buriganga was found to be in the range of 1.0 × 10 5 to 42.0 × 10 5 cfu/ml while enteric bacterial counts on SS agar and MacConkey agar were 0

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Salad vegetables are often consumed fresh and thus can act as effective media for the transmission of associated pathogens. Fresh samples of cucumber, carrot and lettuce were collected from different markets in Dhaka metropolitan city, Bangladesh. Bacterial loads were found to be 7·1 times 104 to 6·34 times 108 colony forming unit (cfu)/100 g. Escherichia coli, Klebsiella, Enterobacter, and Serratia were amongst the coliforms (lactose fermenters) while Pseudomonas, Shigella and Acinetobacter were non‐lactose fermenters associated with the samples.

Bangladesh J. Bot. 36(1): 61-68, 2007 (June)