Background:The growing public health concern caused by non-communicable diseases in urban surroundings cannot be solved by health care alone;therefore a multidisciplinary approach is *** study aimed to evaluate the ai...
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Background:The growing public health concern caused by non-communicable diseases in urban surroundings cannot be solved by health care alone;therefore a multidisciplinary approach is *** study aimed to evaluate the airborne aerosol pollution level in primary schools as possible factor influencing origin and course of the diseases in ***:Seasonal aerosol particle number concentration(PNC)and mass concentration(PMC)were studied in the randomly selected eleven primary schools in the Lithuanian capital,Vilnius,as model of a middle-size Eastern European *** PNC in the size range from 0.01 to>1.0μm in diameter was measured using a condensation particle *** an optical particle sizer,PNC was measured and PMC estimated for particles from 0.3 to 10.0μm.A descriptive statistics was used to estimate the aerosol pollution ***:During all seasons,local cafeterias in the absence of ventilation were the main sources of the elevated levels of indoor PMC and PNC(up to 97,500 particles/cm3).The other sources of airborne particulates were the children’s activity during the lesson breaks with PMC up to 586μg/*** furniture,carpets in the classrooms and corridors were responsible for PMC up to 200μg/*** aerosol pollution(up to 18,170 particles/cm3)was higher for schools in city *** air pollution in classrooms also resulted from intermittent sources,such as construction work during classes(200-1000μg/m3)and petrol-powered lawn trimmers(up to 66,400 particles/cm3).Conclusion:The results of our survey show that even in a relatively low polluted region of Eastern Europe there are big differences in aerosol pollution within middle-sized *** efforts are needed to improve air quality in schools:more frequent wet cleaning,monitoring the operation of ventilation systems,a ban on construction works during school year,on a use of sandblasting mechanisms in the neighborhood of schools.
Structural, electronic and mechanical properties of ZnO/Graphene(ZnO/G) nanolaminates fabricated by low temperature atomic layer deposition(ALD) and chemical vapor deposition(CVD) were *** performed scanning and...
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Structural, electronic and mechanical properties of ZnO/Graphene(ZnO/G) nanolaminates fabricated by low temperature atomic layer deposition(ALD) and chemical vapor deposition(CVD) were *** performed scanning and transmission electron microscopy(SEM/TEM), X-ray diffraction(XRD), electron energy loss spectroscopy(EELS), Raman spectroscopy, X-Ray photoelectron spectroscopy(XPS) and nanoindentation to characterize the ZnO/G nanolaminates. The main structural and mechanical parameters of ZnO/G nanolaminates were calculated. The obtained results were analyzed and interpreted taking into account mechanical interaction and charge effects occurring at the G-ZnO interface. The influence of graphene sublayers number on the mechanical behavior of the ZnO/G nanolaminates was studied. By reducing the bilayer thickness, the mechanical parameters of the films can be tuned(Young's modulus100-200 GPa, hardness 3-9 GPa). The softer response of the multilayers as compared to the single layers of ZnO and graphene was attributed to the structural changes in the ZnO layer and the interfaces. This study shows the mechanical behavior of ZnO/G nanolaminates and their influence on the development of novel electro-optical devices based on these structures.
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