The production of petroleum‐based polymers in huge amounts is perilous for our ecosystem and oil reserves. The use of biodegradable polymers instead of synthetic polymers for various commodity, engineering, and biomedical applications remains the overriding concern of the researchers in last decades. Although poly(lactic acid) (PLA) is considered to be the most befitting substitute for conventional petroleum‐based products because of its superlative mechanical properties, material & processing cost, and non‐toxicity, they have some consequential limitations for various applications because of their slow rate of crystallization, low thermal stability, high brittleness, and low toughness. To overwhelm these deficiencies during the last two decades, researchers have developed various techniques to tailor the properties of PLA, that is, blending with other polymers or using additives such as nanofillers. Among all the nanofillers, for example, carbon nanotubes and organoclays, polyhedral oligomeric silsesquioxanes (POSS) was found the most promising nanofiller because of its organic and inorganic nanostructure and fine dispersion into PLA matrix. This article reviews all the investigations relevant to POSS incorporation into PLA or blends of PLA with other polymers to compare the mechanical, morphological, and physical properties of the ameliorated composites and the neat PLA.

Poly(butylene succinate) (PBS) is a worthy biodegradable thermoplastic polyester for blending along with other biopolymers, especially with poly (lactic acid) (PLA), to overcome its inadequacies in mechanical and thermal characteristics. Since binary blends of PLA and PBS showed that they are incompatible, compatibilization is required. In this work, multi‐epoxide polyhedral oligomeric silsesquioxane (Glycidyl POSS) was added to PLA and PBS using the melt blending method to make them compatible. The blends were prepared at different weight ratios having different amounts of compatibilizer. SEM analysis showed that the Glycidyl POSS impacted the interfacial adhesion and other properties of PLA and PBS blends. Noticeable improvements in mechanical properties were revealed by tensile and impact test results. Tensile strength and Young's modulus were improved when epoxy‐POSS was added up to 1 and 3 wt% into ternary blends, but further increasing POSS concentrations resulted in lower values. FTIR analysis showed a strong interaction between the epoxide group of POSS and the end groups of PBS or PLA. The thermal properties of samples were analyzed using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The shifts in glass transition temperatures of the PLA phase towards lower values appeared in DSC, confirming the enhanced compatibility of PLA and PBS. Also, the reinforcing ability of the POSS inorganic core structure impacted the thermal stability of the blends.

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The disposal of untreated industrial effluent into receiving water courses has become a major environmental challenge being faced by most of the developing countries. The high-strength and toxic wastes are responsible for a variety of water-borne diseases. In Pakistan numerous industrial units that dispose their effluent directly into receiving stream without any treatment. This study was, therefor designed to assess the wastewater characteristics of some major industrial units in the surrounding area of River Kabul, which is one of the most signifi cant resources of water in the north region of the country.The main objectives of this study were to evaluate the wastewater characteristics of some major industrial units in terms of BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), and TSS (Total Suspended Solids) etc. For this purpose, various representative samples were collected from the major industrial units like sugar, paper, ghee (Butter) and textile mills, and were analyzed using standard laboratory techniques. The results indicates that the BOD of sugar, paper, ghee (butter) and textile mills is in the range of 2235mg/L, 1150mg/L, 844mg/L and 745mg/L, respectively. Whereas, the COD of sugar, paper, ghee and textile mills was noticed to be 3945mg/L 2045mg/L, 2240mg/L and 1244mg/L respectively. Owing to the disposal of such highstrength wastes water without treatment, a remarkable increase in the TSS from 96 to 382mg/L, and decrease in DO (Dissolved Oxygen) concentration from 8.8 to 6.7mg/L of River Kabul was observed. The results of this study suggest that all the wastewater coming from the industrial sources should be properly treated as an integral part of their production before their fi nal disposal into River Kabul to secure its natural water quality.DOI: http://dx.doi.org/10.3126/hn.v8i0.4924Hydro Nepal: Journal of Water, Energy and Environment Issue No. 8, 2011 JanuaryPage: 44-47Uploaded date: 23 June, 2011

Water is an important of life. When it is polluted, it disturbs not only human but also aquatic life. There are no of chemicals that contaminate the water. Industries generate different types of chemicals, which pollute the water. Effluent from these industries contains heavy metals, BOD, COD and phenolic compounds. Water pollution is a very serious issue. Different ways are available to treat the waste water. Flocculation, sedimentation, coagulation, photolysis and electrochemical methods are used for treatment of waste water. Phenolic compounds are the most harmful chemicals present as contamination in waste water. Phenolic compound accompanied with chlorine can exist as monochlorophenol, di-chlorophenol and tri-chlorophenol. These compounds are very carcinogenic in nature so their presence is dangerous for human as well as aquatic life. In this research electrochemical method is used to treat o-chlorophenol. Effect of electrodes, voltages and treating times on the removal efficiency have been studied. Stander sample of 100ppm from stock material have been prepared as an analogues to the waste water of industries. HPLC/UV detector is used to analyze the treatment effects. Graphite electrode, 20 volts and 20 min operating time is the most effective parameters that removes about 60% of the initial concentration of 2-CP (ortho-chlorophenol).