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Native starch has low adsorption ability due to lack of specific functional groups. To increase the adsorption efficiency of native starch, it needs to be chemically modified. The modification produces specific functional groups on the backbone of starch and increases its adsorption efficacy towards dyes and heavy metals. The modified starch-based adsorbents (succinylated starches, starch phosphate, starch-based composites and nanoparticles, starch-based hydrogels, cross-linked and carboxylated starches and so on) are more useful due to their large surface area, available polar sites and reproducibility in the degree of activation. In this review article we have discussed the application of modified starches as sorbents for the removal of dyes and heavy metals from wastewater. It further highlighted the optimized conditions used for the removal of heavy metals and dyes by the modified starches and the interactions generated between the adsorbent and adsorbate. This article presented the most recent literature and will spark new ideas for researchers working in this field.

Phenol is the toxicant present in cigarette smoke that causes pulmonary diseases, eyes infection, and even various kinds of cancer. So, in this research, an attempt was done to prepare a suitable absorbent to remove phenol from cigarette smoke. A novel bio-based adsorbent succinylated carboxymethyl starch (S-CMS) was prepared by reacting carboxymethyl starch (CMS) with succinic anhydride (SA) in the presenting of N, N-dimethylformamide (DMF) solvent and pyridine. The structure of the S-CMS was confirmed by spectroscopic techniques including proton nuclear magnetic resonance and Fourier transform infrared. The S-CMS crystallinity and thermal properties were checked by x-ray diffraction and thermogravimetric analysis. The results showed a decrease in thermal properties and crystallinity for S-CMS. The S-CMS were tested as adsorbents for the removal of phenol. The adsorption efficiencies of CMS, S-CMS1, S-CMS2, and S-CMS3 towards phenol were shown to be 0.297 g/g, 0.321 g/g, 0.322 g/g, and 0.324 g/g, respectively.

Succinylated starches (SS) were prepared by the reaction of normal starch (NS) and porous starch (PS) with succinic anhydride (SA) in the presence of DMF solvent and base pyridine, respectively. The proton nuclear magnetic resonance and Fourier transform infrared were used to confirm the successful synthesis of the SS (SS1, SS2, SS3 and SS4, respectively). The X-ray diffractometer XPert PRO (Cu Kα, λ = 1.54 A) was used to study the crystallinity of NS, PS and SS. The XRD analysis showed that the SS exhibited amorphous nature after succinylation. Thermogravimetric analysis and differential thermal analysis of NS, PS and SS showed that succinylation decreased the thermal stability. The morphology of the NS, PS and SS was studied by SEM. These SS were used as adsorbents for phenol removal. The adsorption efficiencies for phenol by NS, SS1, SS2, SS3 and SS4 were found to be 0.084 g/g, 0.165 g/g, 0.173 g/g, 0.183 g/g and 0.189 g/g, respectively.

The development of telecommunication instruments and electronic devices caused a number of subtle electromagnetic radiations, which have adverse effects on the equipment and especially the health of humans. To date, in order to reduce the harmful radiations, considerable attention has been given to the microwave absorbers due to their several attributes, such as cost-effectiveness, environmental stability and lightweight. Given that polyaniline possesses all above-mentioned properties, in this review, we mainly focus on preparation methods and application of polyaniline-based composites as microwave absorbers, including polyaniline/carbon material composites, polyaniline/magnetic material composites and polyaniline/carbon material/magnetic material composites, and the mechanisms of electromagnetic (EM) wave dissipation have also been discussed. The polyaniline-based composites are more efficient for microwave absorption due to their unique properties; therefore, they could be considered as good materials for microwave absorbers to hinder the EM radiations.

To overcome the migration problems of burning rate catalysts (BRCs), ferrocene-based amide compounds (AM-Fcs) were synthesized. The successful synthesis of AM-Fcs were confirmed by proton nuclear magnetic resonance, and Fourier transform infrared spectroscopy. The electrochemistry behaviors of AM-Fcs were examined by cyclic voltammetry (CV). The CV experimental results indicated that these AM-Fcs showed good electrochemical performances, which were contributable to their burning rate (BR) catalytic activity in composite solid propellants. The anti-migration test of AM-Fcs verified significantly slower migration than ferrocene and the most commonly used BRCs catocene. Thermal stability and BR catalytic impact of AM-Fcs on the thermal decomposition of ammonium perchlorate (AP) were studied by thermogravimetry and differential thermogravimetry. These AM-Fcs revealed good catalytic behaviors on the thermal degradation of AP.

In this study, poly(cyclotriphosphazene-co-piperazine) p(HCCP-co-PIP) nanospheres were prepared. The successful preparation of the p(HCCP-co-PIP) nanospheres was confirmed by FT-IR, SEM, TEM, XRD, ...

Poly(methyl silsesquioxanes), PMSQ, are cyclic siloxanes with unusual features that are also widely known as silsesquioxanes due to their organic peripheral and inorganic silicate interior. These are organosilicon compounds with the chemical formula [RSiO3/2]n that are called silsesquioxanes where R may be alkyl, alkoxyl or aryl. These hybrid materials are quite famous to exhibit garner properties from their different inorganic and organic parts in a synergistic way. However, dealing with long-standing challenges and environmentally friendly requirements, we synthesized these PMSQ fine nanoparticles in our own laboratory. These nanoparticles were uniformly dispersed in a bio-based epoxy resin, and the mechanical properties, adhesive strength, and morphology of resultant nanocomposites were evaluated. PMSQ were found to be successfully dispersed into the bio-based epoxy resin in varying weight fractions of 1 wt%, 3 wt% and 5 wt%. The mechanical properties of PMSO-loaded epoxy resin samples are reported as functions of processing parameters. The highly dispersed PMSQ/bio-based epoxy resin nanocomposites showed high tensile modulus and strength values. In addition, it was found that fracture toughness values of all samples prepared by ultra-sonication were increased by increasing PMSQ content in nanocomposites. The corresponding synthesized epoxy resin composites were characterized by different techniques including, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). SEM analysis reported high uniformly dispersed spherical PMSQ particles in epoxy resin. The bonding properties including, tensile modulus and strength of PMSQ were determined using a general testing machine. The obtained results confirmed a significant improvement in bonding performance of PMSQ dispersed in bio-based epoxy resin. PMSQ attracts feasible widespread applications in mechanical and environmental engineering.

Among metals, AgNWs are considered to be excellent materials for use in surface enhancement Raman spectroscopic (SERS) sensing due to their superior electrical properties, strong electromagnetic field generation and strong enhancement intensity. Herein, we used a simple conventional polyol method to synthesize AgNWs feasibly in 40 min under Ar inert atmosphere without using any inorganic salts; only high molecular weight PVP was used as a capping and growth controlling agent, while ethylene glycol was used as a solvent as well as a reducing agent and silver nitrate was used as a Ag source. The polyol-synthesized smooth surface AgNWs were then subjected to chemical etching using aqueous ammonia and 30% hydrogen peroxide as etchant materials, and corrugated surface AgNWs were successfully prepared. The as-synthesized corrugated surface AgNWs were used as surface enhancement materials to increase the intensity of Raman signals, and the surface enhancement properties of the corrugated surface AgNWs were studied using rhodamine 6G as a probe molecule via SERS sensing. The results showed that the AgNWs were successfully prepared in 40 min of reaction; also, corrugated surface AgNWs were prepared, and their corrugated surfaces resulted in high intensity SERS signals.

Herein, poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-(methacrylohydroxyhexane azobenzene)s) (P(FHEMA-co-MAZOHE)s) were prepared by random copolymerization and were characterized by proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC) to confirm the structures and molecular weights respectively. Thermal variations were analyzed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) techniques. Finally, redox and photo stimuli-responsive properties were confirmed by cyclic voltammetry (CV) and ultraviolet–visible spectroscopy (UV–vis) respectively. The results revealed that (P(FHEMA-co-MAZOHE)s) can be useful as information storage materials.

In the current research, we observed numerous suggestions are promoting the use of bio-based epoxy resins, replacing the petroleum-based products like Diglycidyl ether of bisphenol A type epoxy resin DGEBA. With the passage of time, the impending challenges include preparation of environmentally-friendly epoxy with minimum toxic side effect and improved properties. Therefore, we describe a very useful method for preparing new silicone-bridged dimethyl siloxane monomers in high quantity, derived from naturally occurring eugenol. By putting the methyl siloxane, computed with different chain lengths into their molecular backbone. Such epoxy monomers have different molecular structure with high purity. This dimethyl siloxane epoxy, with lower viscosity than commercial DGEBA epoxy, has superior thermal properties, which were evaluated using differential scanning calorimetry DSC. Modification of CMS increases the hydrophilicity. Bio-based epoxy (self-prepared) resin improved adhesive properties, with the help of modified CMS. This study presents a very easy and effective chemical modification to enhance interfacial adhesion composites with superior properties.

We have studied the advances made in chemical modification of cellulose nanocrystals (CNCs) and their corresponding applications. Different synthetic methods such as esterification and etherification, cross-linking and grafting techniques parameters, etc., are used in CNCs formation. As CNCs are well studied for their renewable purposes like oxidation, grafting, copolymerization reaction, etc. Their biodegradability is of great advantage as it can easily be modified with other related functional groups giving high stiffness, strength, low density and long life to metals and other materials. Cellulose polymer is mostly used due to its neutrality and its wide applications in furniture, packaging, textile, food medical products, etc. Mankind has found a great deal of benefit from cellulose owing to its many applications over a period of hundreds of years. This review presents a detailed account of pronounced effect of CNCs, revealed during their numerous applications and their potential use in wide ranging fields. The recent research reveals multidimensional properties and great advancements of CNCs made at an industrial level. CNCs also exhibit high efficiency in all application areas, described in detail here.

With the development of society, plastics play a significant role in daily supplies owing to their advantages. Whereas, insufficient scratch resistance and vulnerable plastic surfaces result in the constraint of their range of application fields, for instance, electronic products. Hence, it is a highly desirable objective of researchers to investigate hardening coatings for protecting plastic surfaces, by selecting polyurethane acrylate (PUA) as film-forming materials attributing to their adjustable features. This article reveals components of PUA and principles for its hardening modification, and summaries various methods of hardening modification of PUA-based coatings, such as improving the crosslinking density, strengthening hydrogen bonding, incorporating rigid groups into molecular structure, introducing inorganic nanoparticles into resin matrix and transferring linear PUA into hyperbranched analogs. Moreover, optimal strategies for the preparation of PUA-based hardening films from above five tactics are discussed.

Synthetic dyes are commonly utilized in various industries like food stuff, synthetic plastics, textile, paper, plastic, leather, and cosmetic industries. Some part of these dyes are drained back in to the environment, where these dyes cause different diseases like cancer, irritation to skin, respiratory tract and eyes. So removal of dyes from water is the need of time. Here, three different starch-g-polymethyl methacrylates (S-g-PMMAs) were synthesized by treating starch with different amount of methyl methacrylate in the presence of KPS as initiator in green solvent water. The prepared modified starches were characterized by Proton Nuclear Magnetic Resonance and Infrared spectroscopic Technique which confirmed that synthesis of starch-g-polymethyl methacrylates occured successful. TGA and DTG analysis were carried out to find out the thermal properties of the modified samples. Crystallinity of starch and starch-g-polymethyl methacrylates was determined through XRD analysis which confirmed that crystalline nature of starch was lost after modification. The modified starch with the highest grafting ratio was then applied for the adsorption of Rhodamine 6G form water using various parameters. It was found tremendous adsorbent for Rhodamine 6G.

In this article, starch phosphate-g-poly (methacrylic acids) (SP-g-PMAAs) were synthesized by dual modification. Firstly starch phosphate (SP) was synthesized by phosphorylation of native starch (NS) with mono sodium-phosphate and di sodium-phosphate. Afterwards, methacrylic acid (MAA) was grafted onto SP via free radical polymerization to synthesize SP-g-PMAAs. The structure of the SP and SP-g-PMAAs was investigated by phosphorus nuclear magnetic resonance, proton nuclear magnetic resonance and fourier-transform infrared spectroscopy. The X-ray diffraction studies showed that the modification diminished the crystalline nature of SP and SP-g-PMAAs. The SEM images showed spherical or polyhedral smooth surface for the starch. After modification, SP and SP-g-PMAAs exhibited distorted and rougher surfaces which are assumed to be good for adsorption. The dual modification produced phosphate and carboxylic groups on the starch backbone. The phosphate and carboxylic groups have high tendency to make hydrogen bonding with phenol. The comparative adsorption studies of NS, SP and SP-g-PMAAs were checked for phenol. The experimental results showed adsorption efficiencies of 0.022 g/g, 0.082 g/g, 0.100 g/g, 0.148 g/g and 0.151 g/g for NS, SP, SP-g-PMAA1, SP-g-PMAA2 and SP-g-PMAA3, respectively. The following findings revealed that dual modification enhanced the adsorption ability of NS.

Isatin is an indole derivative firstly synthesized in the laboratory by Erdmann and Laurent by oxidation of indigo pigment having chromic acid. It is orange-red in color with freezing point 2000C...

Isatin is an important class of nitrogen containing heterocyclic aromatic compounds, found in plants, human blood and tissue...

The Burning rate of a solid propellant predominantly influences its internal ballistic behavior and it has been well known that incorporation of small quantities of certain classes of organic and inorganic substance to a propellant can drastically alter its burning rate characteristics. The inclusion of energetic materials and burning rate catalysts (BRCs) from the metallocene family (e.g., ferrocene (Fc) and 2,2-bis (ethylferrocenyl) propane also known as catocene (Cat)) has been a promising avenue for efficiently increasing the burning rate of propellants. Fc-based materials are dominantly used as burning rate catalysts in solid propellants because of their low volatility, higher compatibility with organic binders, microscopic homogeneities in distribution, broad range of burning rate adjustments, better ignitability and distinct catalytic features. However, in solid composite propellants, Fc-based polymers and derivatives show undesired properties of high migration, that is travelling out from propellant grain to surrounding insulation material on prolong storage, evaporation or sublimation loss during processing and curing as well as phase separation by crystallization in low-temperature applications, limiting their application as BRCs. This article outlines the latest synthetic advancements in the field of Fc-based BRCs, as well as highlighting their catalytic and anti-migration mechanisms.

Cigarette smoke contains a lot of harmful chemicals which cause different diseases like cancer, heart disease, bronchitis and ulcer etc. Ammonia and phenol are among those chemicals which cause cancer, fibrosis, respiratory disorder and pneumonia. So, to remove ammonia and phenol from cigarette smoke, five different types of carboxymethyl starch- g -polyacrylic acids (CMS- g -PAAs) were synthesized by using different initiators, different mole ratio of acrylic acid to CMS anhydroglucose unit (AGU) and different amount of water. Three types of modified CMSs, CMS- g -PAA1, CMS- g -PAA3 and CMS- g -PAA4 were selected for further characterization and application for ammonia and phenol adsorption. The 1 H NMR and FT-IR spectroscopy confirmed the successful grafting of PAA on CMS. Crystallinity of CMS and three modified CMSs was checked by their XRD analysis. The XRD analysis showed that CMS had crystalline nature which was lost after modification. The thermal properties of CMS and the modified samples were checked by TGA and DTG which also gave information about the successful grafting on PAA on CMS. Finally the modified CMSs were further used for the adsorption applications of ammonia and phenol from the gaseous stream. It was found that CMS- g -PAA4 showed the highest adsorption efficiency towards ammonia (0.352 mmol/g) and phenol (0.18 mmol/g).

Silver nanowires (AgNWs) have attracted growing interest because of their wide range of applications in modern nano electronic appliances. During polyol method, the presence of cations and anions in the reaction solution has influence on the final morphology of AgNWs. Here we report a feasible way to prepare AgNWs by polyol method. Copper bromide (CuBr2) salt was used to provide anions and cations in the reaction solution. The anions (Br−) helps in reducing the amount of free Ag+ by forming silver bromide (AgBr) during initial silver seeds formation and the cations scavenge oxygen from the surface of AgNWs during preferential growth of the AgNWs. Ethylene glycol (EG) was used as a solvent and reducing agent, silver nitrate (AgNO3) was used as Ag source and polyvinyl pyrrolidone (PVP) was used as a capping agent. The effects of various factors which influence the final morphology of AgNWs were studied. AgNWs were successfully synthesized in the presence of CuBr2 salt. The morphology of the synthesized AgNWs was characterized by the SEM and TEM. The crystallinity was characterized by HRTEM, SAED and XRD. The LSPR peaks of Ag nanostructures were revealed by UV–Vis spectroscopy. The conductive properties of AgNWs thin conductive films were studied by coating the synthesized nanowires on polyethylene terephthalate (PET) substrate.

Water remains one of the most important mediums for the survival of Living organisms. However, because of the human activities, it has lost its nature and becomes extremely polluted. Among various pollutants, the synthetic dyes have huge contribution for the contamination of the natural water bodies because of their vast application in food, cosmetics, pharmaceutical, textile etc. The presence of such hazardous contaminants causes cancer, kidney failure, dysfunction of brain, infertility etc. Consequently, their removal is indispensable prior to releasing them in natural water resources. Here, low cost adsorbent (activated carbon) was prepared from date palm trunk fiber by using chemical activation using H 3 PO 4 as activating agent. That was utilized for removal of basic cationic dye Malachite Green as a model dye from water by using the Batch adsorption method. The effect of different parameters including adsorbent amount, pH and contact time were studied. The optimum conditions determined were adsorbent dosage 0.5g, contact time 20 minutes and pH5-7. From the result, we conclude that activated carbon of date fiber remains an efficient adsorbent for removal of Malachite Green and may prove the best low cost adsorbent for other dye effluents and wastewater treatment.

Recently, metal organic frameworks (MOFs) have attracted tremendous research attention in many fields, including gas separation, wastewater treatment, energy storage and conversion, catalysis, sensors, etc. To satisfy various demands of special practical applications, the pristine MOFs were usually hybridized with other molecules to form multifunctional materials. Due to their unique reversible redox properties, outstanding optical and electrochemical activities, ferrocene (Fc) and its derivatives have been employed as the guest molecules or functional units in MOFs, these Fc-contained MOFs usually exhibit unique performance in many fields compared with pristine MOFs and bare Fc molecules. In this review, the recent progresses of Fc-contained MOFs and their derived materials are reviewed, including the role of Fc in Fc-contained MOFs, synthesis methods and corresponding applications. The challenges and potential research directions of Fc-contained MOFs are also presented and highlighted.

Cigarette industry plays an important role in the economy of the advanced countries. But the cigarette smoke contains toxic chemicals such as phenol which causes various kind of diseases and affect human life. In this paper, we synthesized carboxymethyl starch grafted poly vinyl imidazole (CMS-g-PVIs) by reacting carboxymehtyl starch (CMS) with vinyl imidazole (VI). The structures of the CMS-g-PVIs were investigated by 1H NMR and FT-IR. The crystalline properties of the CMS and CMS-g-PVIs were checked by XRD. The thermal properties of the original CMS and CMS-g-PVIs were investigated by TGA analysis. It was found that the modified starches had high thermal stability due to aromatic imidazole ring. The modified starches also showed more rough and distorted morphology as compared to native CMS. The CMS-g-PVIs were subjected for phenol adsorption and showed adsorption efficiencies of 0.170 g/g, 0.190 g/g, 0.192 g/g and 0.199 g/g for CMS, CMS-g-PVI 1, CMS-g-PVI 2 and CMS-g-PVI 3, respectively. Due to higher grafting ratio, CMS-g-PVI 3 showed good adsorption efficiency of 0.199 g/g for phenol. The obtained results showed that the grafting of vinyl imidazole on CMS can increase the adsorption efficiency of native CMS towards phenol.

Efficient composite solid propellants possess stable burning rate (BR) and low-pressure exponents. To achieve the ideal performance of propellants, addition of burning rate catalysts (BRC) to the propellants system is one of the best choice. BRC are of tremendous notable significance in composite propellants for their distinctive feature to positively enhance the operational efficiency of solid propellants. In this regard, many valuable kinds of BRC have been synthesized. Due to their better ignitability, ferrocene-based compounds are well-known class of BRC. However, considerable migration and diffusion tendency of this developed class of useful compounds during storage procedures of composite solid propellants limit their practical use as an ideal BRC. This article reviews recent advances in the active field of Fc-based derivatives. In gradual addition, this article also highlights recent progress of Fc-based derivatives as a BRCs and adequately discuss their significant improvements in anti-migration properties.

In this study carboxymethyl starch grafted poly(methacrylic acids) (CMS-g-PMAAs) were synthesized by treating carboxymethyl starch with methacrylic acid in the presence of initiator potassium persulfate (KPS). The modified starches were characterized by proton nuclear magnetic resonance (1H NMR) and fourier-transform infrared (FT-IR) spectroscopy. The crystallinity of the modified starches was analyzed by x-ray diffraction (XRD) while thermal properties of the modified starches were found out by thermogravimetric analysis (TGA) and differential thermal analysis (DTG). These modified starches were then tested as an adsorbent for the removal of ammonia and phenol from the gaseous mixture. The maximum adsorption efficiencies of CMS, CMS-g-PMAA1, CMS-g-PMAA2, and CMS-g-PMAA3 for ammonia were 0.005, 0.020, 0.023 and 0.031 g/g respectively. Similarly, for phenol, the maximum adsorption efficiencies of CMS, CMS-g-PMAA1, CMS-g-PMAA2 and CMS-g-PMAA3 were shown to be 0.2085, 0.2445, 0.2473 and 0.2501 g/g respectively. It was shown that CMS-g-PMAAs could be used as an additive in cigarette filters to remove the toxicant ammonia and phenol from cigarette smoke.

Starch is a homopolysaccharide made up of glucose units which are linked together via a glycosidic linkage. This biopolymer is well known for its low cost, biodegradability, renewability and easy availability. In spite of all these beauties, starch has some problems with their solubility in water, retrogradation, loss of viscosity due to rupturing of glucosidic bond when subjected to treatment and absence of some groups of primary importance like different functional groups especially carboxylic group, ester group, ether group and amino group. In order to overcome these shortcomings and enhance its applications, starch must be modified. The modification can be done chemically, physically and enzymatically, but noteworthy one is the chemical modification. In this review article, we focused on the recently used ways of chemical modification such as acid hydrolysis, cross-linking, acetylation/esterification, dual modification, oxidation and grafting of starch, and their properties. This review article highlighted the application of modified starch as an adsorbent for the removal of ammonia, phenol, heavy metals, and dyes.

Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya fever, filariasis, encephalitis, West Nile Virus infection, etc. It is estimated that more than 700 million people become ill each year from mosquito-transmitted disease and 3 million people die from malaria, including one child every 30 seconds. In response, numerous measures have been used to protect people from mosquitoes, such as chemical, biological, environmental and personal protection. Currently available repellents are either synthetic chemicals like Ethyle hexanediol (EHD), ethyl-3 (N-butylacetamidp) propionate (IR3535) or N, N-diethyl-m-toluamide (DEET), or plant derived chemicals such as Citronella, eucalyptus & lemongrass. The drawback of using plant-based repellents is that many of them are made up of relatively volatile constituents and are generally not effective over long periods of time. The best-known chemical insect repellent is N, N-diethyl-3-methylbenzamide (DEET). The efficacy of DEET providing a long-lasting protection of up to 8 hours from time of application against many blood feeding insects has been documented in several studies. In the present study, Bite-Free a indigenously developed mosquito repellent cream, in which active ingredient is DEET (25% w/w) was evaluated for its efficacy under controlled laboratory conditions, using arm in cage method, based on a WHO standardized procedures (WHO/HTM/NTD/WHOPES/ 2009.4) against three major disease vectors: Anopheles, Culex and Aedes mosquitoes, in comparison of its compatible, commercially available mosquito repellents, "A". The study was conducted at Centre of Excellence in Science and Technologies (CESAT), Islamabad-Pakistan from June, 2013 to June, 2016. Mosquito colonies were reared in Insectory and maintained at 27–32 °C and 60%–70% relative humidity. All collected mosquitoes were morphologically identified by using the key ZOOTAXA-589 (2004) under stereomicroscope model No.1106. Approximately 200 adult mosquitoes aged 7 to 10 days old were used in this trial. Before the beginning of study, informed consent was obtained from all volunteers. During the trial all volunteers were monitored for possible side-effects of the repellent. A medical doctor was on hand during the trials to respond to any side effects. Protective Efficacy of BiteFree was found 91.5% & protection time was 6–7 hours and no any side effect was observed during trials. While Protective Efficacy of commercially available mosquito repellent reference lotion "A" was 86.4% & protection time was 6–7 hours. Irritation and redness of skin were noted in few subjects. Shelf life of BiteFree was 03 years and reference lotion "A" shelf life was found one year.

Different copolymers (poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-methacrylo-4-aminoazobenzene-co-methacrylic acid)s) (P(FHEMA-co-MAZO-co-MAA)s) were synthesized and their different properties were analyzed in this work. Methacrylic acid was introduced as a side group to possibly affect the photostability. The synthesized copolymers were characterized by nuclear magnetic resonance (1H NMR) spectroscopy and gel permeation chromatography (GPC). Thermal studies were performed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) analysis, which showed that the copolymers were thermally stable under the operating conditions of the information storage devices. Redox studies and photoresponsive studies were performed by CV technique and UV/vis spectroscopy which showed that these copolymers contained good redox and photoresponsive properties. The obtained results paved the way towards the four states information storage of the materials.

Five ferrocene (Fc)-based compounds (HQ-Fcs) were synthesized by the condensation reaction of ferrocenecarbonyl chloride with corresponding hydroquinone derivatives. Nuclear magnetic resonance (1H NMR), and Fourier transform infrared (FT-IR) were used as evidence for the synthesis of HQ-Fcs. The electrochemical properties of HQ-Fcs were investigated by cyclic voltammetry (CV) and suggested that these compounds exhibited redox behavior due to ferrocene groups. The burning rate catalytic effect of HQ-Fcs was examined by Thermogravimetric (TG) and differential Thermogravimetric (DTG) techniques. Thermal analysis results indicated that HQ-Fcs were thermally stable and have better burning rate catalytic effects in accelerating thermal decomposition of AP. Anti-migration behavior of HQ-Fcs in comparison to commonly used 2,2-bis (ethylferrocenyl) propane (catocene) and Fc was evaluated. It was observed that HQ-Fcs delivered excellent anti-migration performances than catocene and Fc.

Aminothiazole organic compounds have diverse biological applications. Herein we report the synthesis of two aminothiazole derivatives: 4-(biphenyl-4-yl)thiazol-2-amine (1) and 4-(2′,4′-difluorobiphenyl-4-yl)thiazol-2-amine (2) via Suzuki-Miyaura cross coupling reaction. The chemical structures of 1 and 2 are confirmed using 1HNMR, 13CNMR, FT-IR, UV–Vis and single crystal x-ray studies. The XRD study reveals that the both solid state structures (1) and (2) are diffused to form poly chain structures due to presence of intra molecular hydrogen bonding (H.B). Furthermore, these compounds were analysed by density functional theory (DFT) at M06-2X/6-311G(d,p), B3LYP/6-31G(d) B3LYP/6-31G(d,p) and B3LYP/6-311G(2d,p) level of theories to obtain optimized geometry, electronic and spectroscopic properties. DFT optimized geometry supports the experimental XRD parameters. Natural bond orbital (NBO) calculation predicted the hyper conjugative interaction and hydrogen bonding in all derivatives. The FT-IR and thermodynamic studies also confirm the presence of hydrogen bonding network in the dimers which agrees well with the XRD results. Moreover, UV–Vis analysis reveals that maximum excitations take place in 1 and 2 due to HOMO → LUMO(98%) and HOMO → LUMO(97%) respectively which show good agreement to experimental data. The first order hyperpolarizability of both molecules is remarkably greater than the value of urea. The global reactivity parameters which are obtained by frontier molecular orbitals disclose that the molecules might be bioactive.

Flexible pavements are the major type of pavement use in recent days. Bitumen is the main constituent’s part of flexible pavement. Bitumen is the by-produce of petroleum. The depleting reserve of petroleum led researcher to look for alternative binder. This research work explicitly aim at replacing certain percentage of bitumen with Tire Rubber powder (TR), Waste Cooking Oil (WCO) in the presence of Bagasse Ash (BA) as a modifier. Physical test were performed to determine optimum percentages of TR, WCO and BA that can be used as a percentage replacement in bitumen. Result shows that up to 20 % of bitumen can be successfully replaced without affecting performance of bitumen. Performance Tests such as Dynamic Shear Rheometer, Rotatory thin film oven, Pressure aging Vessel and Bending Beam Rheometer were performed on modified samples for its physical and rheological properties. Modified bitumen showed good resistance against rutting, skidding and low temperature cracking. The research work directly contribute in developments of alternative binder for flexible pavement which is a leading research trend these days and environmental friendly initiative.

Glutathione (GSH) and sodium tungstate (Na 2 WO 4 ) are important pharmacological agents. They provide protection to cells against cytotoxic agents and thus reduce their cytotoxicity. It was of interest to study the biological activity of these two pharmacological active agents. Different strains of bacteria were used and the zone of inhibition was determined for GSH, Na 2 WO 4 and GSH+ Na 2 WO 4 mixture. The results show high antibacterial activity of GSH as compared to Na 2 WO 4 and Na 2 WO 4 +GSH mixture. It was observed that GSH antibacterial activity was significantly lowered upon addition of Na 2 WO 4 to GSH aqueous solution. The results conclude with the proposed formation of W-SG complex in aqueous solution. Key words: Glutathione, sodium tungstate, antibacterial activity, strains of bacteria.