The paper describes day to day changes observed in atmospheric aerosol's parameters namely AI 300, AOD 550 , , TWC,  and MC from their background reference day value over Udaipur during Pre to Post-Diwali period from 2002 to 2007. Before Diwali to Diwali, daily variations in such aerosol's parameters values show the substantial increase order of 30-60% from their respective background. Afterward Diwali, such change in AI 300 shows the decreasing behavior, in sharp contrast to this, daily variations in AOD 550 ,  and MC exhibit either lower value or attain the same peak value depending upon the corresponding level of TWC and rainfall activity of that particular year. These variations are not instantly but with certain delay in the same period. A considerable amount of implication in aerosols loading is observed in terms of reduction in SHWRF from 20-30% during the enhancement period of aerosol's parameters. However, DSWRF does not show any appreciable change. The main possible causes of increase in aerosol's loadings within above period are discussed in views of inter mixed effect of local emission activity and long range transport of aerosols from heavy polluted IGP site and in reduction of PBL height and wind speed.

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Recycling of electronic circuits in general and Printed Circuit Boards, in particular, are very important for the protection of environment. It is also a good source of rare and costly metals in trace amount and proper recycling of PCBs can help recover these elements with minimum environment cost. Several recycle technologies were reviewed in this paper. From the review, it is observed that there are three main stages of PCBs recycling mainly pre-treatment, physical separation and chemical separation. In pre-treatment stage, crude separation is made and toxic parts as well as parts that can be disassembled are removed. After this process, the physical separation process starts where metallic and non metallic materials are separated after proper size reduction by appropriate technologies. Metallic and Nonmetallic materials are sent for further management. Most of the time chemical separation is used to recover materials. Many scientists are also working to get metallic and non metallic parts separately and developing use of non magnetic materials as sheet so that environment can be effectively protected.

The present study describes the long-term changes in Pre-midnight and Midnight airglow intensities of 557.7 nm during the period 1979-1994 over mid latitude Japanese station i.e., Kiso, Tokyo Astronomical Observatory, University of Tokyo (35.79˚N, 137.63˚E; 1130 m), Japan. It has observed that there is a positive increasing decadal change in Midnight and Pre-midnight mesospheric airglow intensity of the range 25 -88 R. This range is the order of 10% to 30% of the observed MARV and average night airglow intensity of 250 R. Besides this long-term trend, inter-annual monthly variation is also seen from fluctuation of yearly variation of deviation values from MARV to particular average monthly values. The present observations about the positive decadal change in night time mesospheric airglow intensity has been further linked to the reduction of mesospheric electron densities and temperature or shrinking and cooling of the lower ionosphere as established from the long-term behavior of mesospheric parameters such as a negative decadal change in thermal structure, electron density, neutral density parameters as per studies reported by other researchers.

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