2018

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Dye degradation by nanophotocatalysis
(UMT, Lhr, 2018) ZUNAIRA ARSHAD
TiO2/Graphene oxide nanocomposites have been prepared by TiO2 nanoparticles deposition on graphene oxide sheets via liquid phase deposition. This chemical method of Liquid phase deposition has been used for composite preparation due to hydrophobic/hydrophilic incompatibility of graphene oxide with metal oxides.TiO2/GO nanocomposites have larger surface area than that of prepared TiO2 nanoparticles and showed enhanced rate of photocatalytic activity. Crystallinity, dislocation density, specific surface area and anatase phase of TiO2 are estimated by XRD. Average crytallite size of TiO2 calculated from XRD is 12.42 nm and that of GO is 4.01 nm. Characteristic peaks in XRD at 2Ѳ =25.3° and 47.9° are for anatase phase of TiO2. Successful synthesis of GO, TiO2 and TiO2/GO nanocomposites is confirmed by FTIR. Morphology and size of composites and TiO2 nanoparticles are estimated by SEM. The synthesized nanoparticles have uniform distribution on graphene oxide sheets. TiO2 nanoparticles with diameter range of 10-100nm, are found deposited on graphene oxide sheets. 8% nanocomposites showed fastest and highest rate of dye degradation among all composites and pure TiO2 nanoparticles.Excellent photocatalytic activity is attributed to thin two dimensional sheet support, larger surface area, higher adsorption capacity and good electron acceptability of graphene oxide.
Synthesis, characterization and photocatalytic activity of copper doped zinc oxide and its composites with sulphur doped graphitic carbon nitride
(UMT, Lhr, 2018) MUHAMMAD USMAN
Investigation of the doping influence on structures and photocatalytic properties of Zn nanostructures at optimum concentration is presented. Moreover, enhanced photocatalytic performance making composite with sulfur doped g-C₃N₄ is also presented. Copper (Cu) is used as dopant on ZnO nanostructures. Undoped and doped nanoparticles were prepared by co-precipitation method and annealing was done at 520oC for 3 hours. Sulfur doped graphitic carbon nitride nanosample was prepared by using thiourea. Nanocomposites of sulfur doped graphitic carbon nitride with pure zinc oxide and copper doped zinc oxide were prepared. Different characterization techniques were used to analyze the structural properties like (SEM) scanning electron microscopy, (XRD) X-ray diffraction and FTIR spectroscopy. Photocatalytic activities of all the samples were checked by UV- Visible. Methylene blue was employed as an organic pollutant for the photocatalytic activities and sunlight used for this activity. All the sample was good photodegradation of methylene blue. Therefore, 15% Cu doped ZnO was made composites with sulfur-doped graphitic carbon nitride by physical mixing method to determine it effect on photocatalytic activity and the formation of series of nanocomposites. Tauc plots were made by determining the band gap of different nanosample. Nanocomposites are excellent samples for degradation of an organic dyes and can be very effective for removal of organic dyes from industrial waste waters.
Antidiabetic and hypolipidemic activity of cotula anthemoides linn.
(UMT, Lhr, 2018) KHADEJA-AL-KUBRA
Medicinal plants have been used in old times for the treatment of human diseases, because of their reliable and powerful chemical composition. Cotula anthemoides L. is a unique oldest therapeutic weed but have some beneficial practices such as paralysis, headache, scabies, ophthalmia, wound healing and stimulant. It produces a diverse range of different phytochemical constituents like phenolic acids such as ursolic acid and gibberellic acid, flavonoids such as luteolin, apigenin-7-O-β-d-glucuronopyranoside including glucosides (sulfonyl flavonol glucoside, vanillic acid-4-O-β-d-glucopyranoside) and coumarins derivatives which make it effective for various infections. The aim of current work was to evaluate in vitro antidiabetic and hypolipidemic activities, using entire plant of Cotula anthemoides L. (Family: Asteraceae).To evaluate antidiabetic potential, acarbose was used as standard to inhibit the activity of alpha amylase enzyme. Using different concentrations of C.anthemoides extracts, inhibition percentage was observed. For methanolic extracts, the inhibition ranges from 28.36% to 73.85%. These inhibitions were closely associated with that of acarbose inhibition percentages ranged from 33.00% to 82.20%. In case of hypolipidemic effect, orlistat was used as positive control to inhibit the activity of lipase enzyme. Using different concentrations of C.anthemoides extracts, inhibition percentage was observed. For methanolic extracts, the inhibition ranges from 34.17% to 80.31%. These inhibitions were closely related with that of orlistat inhibition percentages ranged from 41.23% to 87.59%. Results showed that the methanolic extracts revealed significant α-amylase and lipase inhibitory action with an IC50 value of 0.0293 and 0.0241 as associated with acarbose (IC 50 value 0.023) and orlistat (IC50 value 0.0178) respectively, which disclosed that methanolic extracts of C. anthemoides inhibition percentages were directly proportional to the concentrations. However, percentages of inhibition were less than standard drugs.
Green synthesis of copper oxide nanoparticles using guaiacum officinale l. Extract
(UMT, Lhr, 2018) HAFIZA IQRA SHAHZADI
Nanoparticles of copper oxide was successfully synthesized from G. officinale leaves extract. G. officinale belongs to family Zygophyllaceae. G. officinale was selected for the CuO nanoparticles synthesis because it has not been reported previously for the synthesis of any type of nanoparticles. Green synthesis by using plant material now become a very effective method for the synthesis of nanomaterials for biological and bio medicinal applications. G. officinale mediated CuO nanoparticles characterized through UV-visible spectrophotometer, FTIR, XRD, AFM and TGA. UV-visible spectra showed absorbance between 250-300 nm indicate the CuO nanoparticles. Peak at 568 cm-1 in FTIR spectra confirm the synthesis of copper oxide nanoparticles. XRD patterns indicate the crystalline nature of CuO nanoparticles and mean size of crystallite was about 57 nm. The average size of synthesized CuO nanoparticles was about 150 nm determined by AFM images. TGA results showed that the synthesized CuO nanoparticles were stable up to 200 ºC. Synthesized nanoparticles were tested for their antibacterial activity by agar diffusion method. The CuO nanoparticles showed clear zone of inhibition against all bacteria. Green synthesized CuO nanoparticles exhibit more effective antibacterial activity. Antioxidant activity of synthesized CuO nanoparticles was also evaluated. Various methods were used for the assessment of antioxidant activity in CuO nanoparticles. TPC (Total phenolic content) and FRAP (ferric-reducing antioxidant power) were used for the evaluation of antioxidant activity. Total phenolic content (TPC) of different concentrations of CuO nanoparticles ranging from 18.4 to 51.4 (mg/L GAE). The total phenolic content (TPC) of CuO nanoparticles increased by increasing their concentration. FRAP values for 3, 2 and 1 mg of CuO nanoparticles were 1.8, 1.6, 1.2 mM FeSO4.7H2O, respectively. The synthesized CuO nanoparticles possess very good antibacterial and antioxidant potential.
Evaluation of plant extract based candelilla wax formulation to improve shelf life of fruits
(UMT, Lhr, 2018) AALIA IRSHAD
Most of fruits and vegetables are available in some specific season and not in others. So techniques have been developed to preserve such seasonal foods intact for later use. Blending extracts of medicinal plants with Candelilla wax as edible coating has been experimented by different researchers. So in present study two medicinal plants were explored because of their reported antifungal activity. Aloe vera (A. vera) is one of the liliaceous plants that has been a commonly used in skin care and pharmaceutical products. A. vera can be a good choice in protecting and prolonging the shelf life of food products. Toona ciliata (T. ciliata) is a large deciduous tree. It has vast application for treatment of chronic dysentery, ulcer, fever and headache. In present work two protecting films are formulated by mixing the extracts of A. vera separately T. ciliata with naturally occurring edible candelilla wax obtained from E.antisyphilitica. This wax was applied on fresh fruits including Golden apples, banana and lemon to estimate the effect of wax for promoting the shelf life of fruits under room temperature at 25o C for about 10 days and analyzed after every 30 hours. To calculate the performance of edible coating different parameters were observed including skin appearance, pH and weight loss. Weight loss in apples coated with ECC ranged from 0.3%-1.9%, ECAV 0- 2.6% and ECTC 0.3-1.9%. In case of Banana weight loss reached to 22.7% in ECC, 19.5% in ECAV and 28% in ECTC. In lemon 18.3% in ECC, 28.9% in ECAV and 44.42% in ECTC. pH values were also determined in apples reached to 6.0 in ECC, 5.5 in ECAV and 5.0 in ECTC. In banana pH values of all films were reached to 6.3 and in lemon all films showed slight difference in pH value i-e 3.0, 2.8 and 2.9 respectively. Fruits were stored at room temperature only banana showed the fungal attack. This application is industrially as well as economically beneficial in terms of maintaining the nutritional quality and browning of skin.
Synthesis of carbon nanoparticles from seed oils
(UMT, Lhr, 2018) MADEEHA RASOOL
Synthesis of carbon nanoparticles was done by utilizing distinctive seed oils (fenugreek seeds oil, pumpkin seeds oil, watermelon seeds oil, poppy seeds oil and funnel seeds oil). Simple combustion technique was applied and it was as efficient technique as other techniques such as chemical vapor deposition, arc discharge and laser ablation techniques. Carbon nano particles having nano range were synthesized by utilizing the above discussed oils by ignition method. The characterization was done by powder X-Ray Diffraction (XRD) system, Thermo Gravimetric investigation (TGA), Scanning Electron Microscope (SEM) and Fourier Transform Infra-Red spectroscopy (FTIR). Surface morphology of these carbon nanostructures was predicted by the help of scanning electron microscopy system. The thermal stability of these nanoparticles incorporated from seeds oil was checked by utilizing thermo gravimetric strategies. Average particle size of nanoparticles was explored by XRD and FTIR results show the presence of functional groups.
Study of newly synthesized cationic surfactants for drug interaction and antimicrobial activity
(UMT, Lhr, 2018) ALI JAAN
Two pyridinium based new cationic surfactants which have synthesized with a different group position of methyl on a pyridine ring and a same long alkyl chain of hydrocarbons have been successfully synthesized. The synthesis involved the reaction of 2-methylpyridine with alkyl halide in a toluene solvent. The synthesized compounds give 90%-95% yield. A tail of those pyridinium based surfactant, directly attached to the pyridinium nitrogen in the presence of bromine which remains present in solution as a counter anion. The newly synthesized cationic surfactants are confirmed by the Fourier Transform Infrared spectroscopy FTIR. The confirmation peaks for sample A1 is 1170 cm-1 and 1209 cm-1 for sample A2. The proton and carbon nuclear magnetic resonance spectroscopy 1H NMR, 13C NMR was also carried out. The C-N confirmation shift can be seen at 58.56 and 61.98 for sample A1 and sample A2 respectively. The spectroscopy and conductometry techniques were used to study the micellization behavior of cationic surfactants. The synthesized compounds showed a critical micelle concentration (CMC) in a very low value range (0.111 mM to 0.125 mM), which actually proves the best surface acting ability of the synthesized compounds. Both compounds efficiently showed an antibacterial activity against the different classes of pathogen bacteria with the various inhibition zones (3 mm to 6mm). The change in Gibb’s free energy (ΔG) were also calculated from their binding constant (K) for sample A1 and sample A2 14.5 KJ/mol and 25.3 KJ/mol respectively. The samples showed the spontaneity of the reactions while interacting with drug molecules. A successful drug interaction proved the efficient bio-availability of drug due to the best incorporation of drug molecules with the aggregated monomers of surfactant (a micelle).
Synthesis, characterization and photocatalytic application of p(aac) microgels and its composites of ni doped zno nanorods
(UMT, Lhr, 2018) SIDRA ARSHAD
ZnO nanorods and Ni doped ZnO nanorods with various nickel 0%, 5%, 10%, 15%, 20%, 25% (mol%) concentration were prepared by co-precipitation method, by adding zinc acetate dihydrate and nickel nitrate dihydrate as zinc and nickel precursor in presence of ammonia solution. Microgels of p(AAc) and its composites of Ni doped ZnO nanorods were synthesized by inverse phase polymerization method under N2 gas atmosphere. Morphology of Ni doped ZnO nanorods and its composite with p(AAc) were determined by XRD, TEM, SEM, FTIR and UV-Visible spectrophotometer. The photocatalytic activity of the samples was testified by using Tungsten lamp of 500 W via photo-degradation of methylene blue (MB) as a standard dye. It was observed that the composite of p(AAc) microgels with Ni doped ZnO nanorods show much enhanced photocatalytic performance upto 93% as compared to any other individual particle acting as alone. The enhanced photocatalytic activity is due to enhanced surface area, surface roughness and decreasing band gap.
Synthesis and characterization of silver doped zno composites with sulphur doped graphitic carbon nitride and their potential applications
(UMT, Lhr, 2018) Naveed Ahmed
This work includes the synthesis of pristine ZnO nanoparticles and a series of silver-doped zinc oxide nanoparticles were carried out by reflux method by varying the amount of silver (1, 3, 5, 7 and 9 % by mol.). The morphology of these nanoparticles were investigated by SEM, XRD and FT-IR techniques. These techniques show that synthesized particles are homogenous spherical nanoparticles having average particle size of about 50-100 nm along with some agglomeration. The photocatalytic activity of the ZnO Nanoparticles and Ag doped ZnO nanoparticles was investigated via photodegradation of methylene blue (MB) as a standard dye. The data from photocatalytic activity of these nanoparticles show that 7% Ag-doped ZnO nanoparticles exhibit much enhanced photocatalytic activity as compared to pristine ZnO nanoparticles and other percentage of Ag doped ZnO nanoparticles. Furthermore, 7% Ag doped ZnO was made composites with sulfur-doped graphitic carbon nitride by physical mixing method and a series of nanocomposites were made (3.5, 7.5, 25, 50, 75 % by weight. It was observed that the 25% composites exhibited the batter photocatalytic performance than pristine S-g-C3N4 and pure 7% Ag doped ZnO. Tauc Plots also support much enhanced photocatalytic activity of 25% nanocomposites by reducing the band gap of ZnO from 3.37eV to 2.32eV in 7 % Ag doped ZnO to 2.17eV in 25% Composites comprising Sulphur doped Graphitic Carbon and 7% Ag doped ZnO.
Synthesis of Ethylene from Bioethanol using Al2O3 Nanoparticles
(UMT, Lhr, 2018) RUBY ANWAR
At present Alumina nanoparticles being monodispersable and ceramic materials are extensively used as catalyst. Aim of this study is the fabrication of alumina nanoparticles by simple sol-gel method, their characterization and use of these nanoparticles as catalyst in dehydrogenation of ethanol to ethylene. Aluminium sulphate was used as precursor in synthesizing alumina nanoparticles. Their successful synthesis was confirmed by UV-visible, AFM, XRD and FTIR. UV-vis. UV-vis showed peak at 273nm. FTIR spectra showed a broad band at 3748–2906 cm−1 assigned to the -OH stretching vibrations related to the lattice of water molecules which probably due to the moisture content in the powder, other peaks at 528 cm−1 and 926 cm-1 assigned to the bending vibrations and symmetric stretching vibration of Al-O-Al bonds respectively. AFM confirmed synthesis of alumina nanoflowers in nano range of 300nm. XRD confirmed mean crystallite size of 37nm. Using these nanoflowers as catalyst, ethylene was synthesized by dehydrogenation of ethanol at 244oC. Alumina nanoflowers gave yield of 77% of ethylene. Synthesis of ethylene was made confirm by Headspace GC-FID and GC-MS.
Antidiabetic and hypolipidemic activity of euphorbia prostrata
(UMT, Lhr, 2018) IQRA MUSHTAQ
In past medicinal plants had been used for the treatment of diabetes and hyperlipidemia because of their antidiabetic and hypolipidemic properties but there was no scientific evidence of it. Aim of present study was to investigate the antidiabetic and hypolipidemic activities of Euphorbia prostrata. It is a small, prostrate, green annual herb and belongs to family Euphorbiaceae. It is applicable for the treatment of wound healing, bleeding hemorrhoids, breathing disorders, tumors, severe diarrhea (dysentery), gonorrhea, and digestive problems etc. Many phytochemicals isolated from this plant such as phenolic acids like gallic acid, ellagic acid ,flavonoids like apigenin, quercetin, luteolin (and their glucosides) and tannins that were responsible for antidiabetic and hypolipidemic activities. Acarbose used as positive control that resists the activity of alpha amylase enzyme. For methanolic extracts of plant inhibition percentages ranges from22.02% to 76.20% against different concentrations that were close to the acarbose inhibition percentages ranged from 33.00% to 82.20%.Orlistat used as positive control that resist the activity of lipase enzyme. For methanolic extracts of plant inhibition percentages ranges from 35.88% to 82.08% against different concentrations that were close to the orlistat inhibition percentages ranged from 41.23% to 87.59%. It was estimated by statistical analysis that IC50 value of acarbose and orlistat was 0.023 and 0.017 and that of plant extracts was 0.029 and 0.022 for antidiabetic and hypolipidemic activity. Results showed that with the increase of concentrations of standards and plant extracts inhibition percentages also increases.
Preparation of biodegradable polymer
(UMT, Lhr, 2018) SEHAR HUSSAIN
The grafting of starch with different monomers like acrylic acid, methyl methacrylate and acrylonitrile was carried out with the free radical polymerization method. Thermal disintegration of potassium per sulphate caused the generation of free radicals at 70oC. The efficient grafting was proceeded by optimizing different parameters through many experiments such as amount of starch, quantity of monomers and temperature, one gram of starch and 6 ml of the monomers. Then carbon nanocomposites of these grafted polymers were prepared by adding 0.05 g of carbon nanoparticles during the course of reaction. The thin films prepared from these carbon nanocomposite were subjected to characterization through SEM, FTIR, tensile strength and biodegradation tests. SEM, FTIR and tensile strength results revealed fruitful information regarding the properties of these materials, while biodegradability was found to be 27.5% in 60 days. In this way grafted polymers with acrylic acid, methyl methacrylate, acrylonitrile, styrene and ethyl acrylate were obtained, characterized by SEM, FTIR and tensile strength techniques.
Bioconversion of fruit seeds to gallic acid
(UMT, Lhr, 2018) RIDA ARSHAD
Gallic acid is phenolic compound present in many plants as secondary metabolite. Gallic acid has industrial importance because of its many uses in foods, healthcare, dyes, paints, photography and inks. The demand of gallic acid internationally is around 8000 tonnes per year. Different microbes have ability for the production of tannase enzyme that is accountable for gallic acid hydrolysis of tannins. Thus the purpose of this research work was to discuss the possibility for gallic acid production from different tannin rich substrate using A.oryzae as tannase source through solid state fermentation. Various fruit seeds were tested for the suitability of the tannase and gallic acid synthesis including apple, guava tamarind jamun and watermelon seed. Amongst various substrate tested, jamun seeds give the highest activity of tannase(30.05 U/g) and gallic acid (16.65 mg/g) at optimized physicochemical parameters i.e.1:3 substrate moisture ratio, 30°C, 96h incubation period with pH 5.5. Addition of 0.2% glucose as source of carbon and ammonium sulphate as source of nitrogen increases the yield of gallic acid. The gallic acid produced was extracted by soxhlet apparatus and identified by FTIR spectroscopy. Quantitative estimation was done by HPLC and was found to be 98.5% pure. This study will be useful for economically and feasible production of gallic acid.
Serum concentration of thyroid hormone in obese women in lahore pakistan - a clinical study
(UMT, Lhr, 2018) UZMA AZAD
We studied and compared thyroid function tests in 265 obese women and as many normal weight women at CENUM mayo hospital Lahore. All of them were female. Their mean (+ SD) age and height was comparable (P>0.05) but average weight, BMI, hip circumference, waist circumference and hip-waist ratio was significantly higher in obese women (P<0.05). Overall incidence of thyroid dysfunction was observed in 42(15.8%) obese patients and 53 (20%) control group patients. Hypothyroidism was detected in 30(11.3%) patients among obese and 19(7.2%) patients from control group. Overt hypothyroidism was observed in 19(7.2%) obese and 9(3.4%) control women. Subclinical hypothyroidism was detected in 11(4.2%) obese and 9(3.4%) control women. Hyperthyroidism was observed in 12(4.5%) patients among obese women, 2 have overt hyperthyroidism and 10 have subclinical hyperthyroidism. In control group 34(12.8%) patients had hyperthyroidism: 15 patients have overt hyperthyroidism and 19 have subclinical hyperthyroidism. Thus incidence of hypothyroidism was more in obese female than control group and incidence of hyperthyroidism was observed more in lean group as compared to obese patients. Acomparison of mean thyroid hormone parameters of euthyroid obese and control women showed that mean FT4 was significantly lower in obese euthyroid women while mean levels of FT3 and TSH were comparable.
Theoretically computed ir and raman spectra of cyclohexane and some derivatives using gamess
(UMT, Lhr, 2018) IQRA SHARIF
Infrared (IR) and Raman spectra of cyclohexane (C6H12) and some of its derivatives of group IVA members i.e. silacyclohexane (C5H12Si), germacyclohexane (C5H12Ge) and stannacyclohexane (C5H12Sn) have been determined theoretically using two different software GAMESS and Gaussian 09. Density Functional Theory (DFT) approach was used for the theoretical infrared and Raman spectra of all the mentioned molecules. For the Infrared and Raman spectra of cyclohexane and silacyclohexane DFT computations, using 3-21G, 6-31G(d,p) basis sets with B3LYP level of theory were performed using GAMESS (U.S 2017). Similarly in Gaussian 09, Def2-TZVP basis set with B3LYP level of theory was used. The results of theoretical infrared spectra of cyclohexane and silacyclohexane have been compared with experimental infrared spectra provided in literature and a good agreement was found between the results. Both Def2-TZVP and 6-31G(d,p) basis set used in Gaussian and GAMESS produced good results. On the basis of the good agreement of theoretical and experimental results of cyclohexane and silacyclohexane we extended our work to predict the theoretical IR and Raman spectra (which have not been explored yet) of other molecules of group IVA, germacyclohexane and stannacyclohexane using the same (Density Functional Theory with B3LYP level using 3-21G, 6-31G(d,p) and Def2-TZVP basis set) approach.
Estimation of medicinal potential of guaiacum officinale
(UMT, Lhr, 2018) JASIA MUNNASS
Many plants have significant therapeutic potential with least side effects. Guaiacum officinale is one of these medicinal plants which have been used as a source of remedies for thousands of years. This plant is commonly known as “the tree of life” because of its medicinal properties. Antibacterial activity was performed to evaluate the antibacterial potential of aqueous, n-hexane and methanolic extracts of G. officinale against four bacterial strains using Amoxicillin as standard drug by agar well diffusion method. The zones of inhibition produced by the extracts at different concentrations showed significant variation in regards to four bacterial strains tested. The diameter of inhibition zones against P. aeruginosa, S. aureus, E. coli, and S. mutans was in the range of 2-14 mm, 1-13mm, 1-11mm and 2-6mm respectively. FRAP and TPC assays were performed to evaluate antioxidant activity of aqueous, n-hexane and methanolic extracts of G. officinale. Results showed that the total phenolic contents of three samples showed variation, ranging from 6.24-38.76 mg of (GAE)/100g. The FRAP values of three samples varied from 0.99-3.88 mM/mL of extracts. Furthermore methanolic extracts of G. officinale were applied on oranges, bananas and lemons to prolong their freshness. The effects of these coatings were evaluated by measuring their weight loss, change in pH and physical appearance. Weight loss percentage in extract coated oranges, bananas and lemons were in the range of 2.5-10.3%, 5.3-13.5% and 6-11.3% respectively monitored for 240 hours while the pH of the selected extract coated fruit showed slight variation during monitoring for 240 hours. The change in pH of oranges was in the range of 3.9-4.4 while the change in pH of bananas and lemons were in the range of 5.2-5.5 and 1.7-2 respectively. Results suggested that extracts of G. officinale possess potent antibacterial and antioxidant properties and could be used as edible coatings to enhance the shelf life of fruits.
Estimation and removal of arsenic from drinking Water using tree barks
(UMT, Lhr, 2018) SAMREEN TARIQ
In the present study the utilization of tree barks (such as wheat bagasse, barks of burr and sheesham) have been utilized for the absorbance of As3+ in aqueous media. For this purpose the standard samples of As3+ were prepared with different concentrations (i.e. 20 ppb, 40 ppb, 60 ppb and 80 ppb). The three barks were obtained from local trees (Triticum aestivum (wheat bagasse), Ficus benghalensis (Burr) and Dalbergia sissoo (Sheesham) from the area of Lahore. The tree barks were broken down into small pieces, air dried and then ground in a mortar pestle. The material obtained was studied for adsorbance of As3+. The percentage of adsorbance of As3+ was calculated by adding the bark powder 5.0 g into 100 ml of 20, 40, 60, and 80 ppb As3+ solutions separately. Arsenic solutions containing barks dipped in, were allowed to stand for 3 hours. After that the concentrations of arsenic were determined colorimetrically using two methods, one standard method given in vogel’s text book of quantitative analysis 5th edition and the same method has been reported by Mary Sohn(2009) as given in vogel’s text book of quantitative analysis 6th edition and by use of gold nanoparticles. The results demonstrated 73% reduction of As3+ by Ficus benghalensis (burr) tree bark, 45% by Triticum aestivum (wheat) and 55% reduction of As3+ by Dalbergia sissoo (sheesham) in water. This study illustrates that Ficus benghalensis (burr) tree bark is more effective adsorbant of As3+ in aquous media among the three barks utilized, and potentially a good adsorbent for arsenic i.e. easy to use and cost effective.
Evaluation of antimicrobial and anti-diabetic potential of parthenium hysterophorus
(UMT, Lhr, 2018) NOOREEN ASGHAR
Parthenium hysterophorus is an aggressive and harmful weed but have some beneficial features. It produces a diverse range of bioactive molecules such as flavonoid, terpenoids, tannins, amino sugars and other phenolic derivatives which make it active against various infections. The aim of current work was to evaluate in vitro anti-microbial and anti-diabetic activities, using P. hysterophorus organic extract concentrations. To evaluate the anti-bacterial and anti-fungal potential, different concentrations of methanolic and wax extracts of P. hysterophorus were used against bacterial strains such as E.coli, K.leb, S.pseduo, S.Aureus and fungal strains S.cerevisiae and C.albicans. Gentamycin and Nystatin were used as positive control for bacteria and fungi respectively. All concentrations were active against all pathogenic organisms. Varied zones of inhibition were observed due to bioactive constituents that disperse at different rates. Range of inhibition zones 11- 21mm in diameter were recorded using methanolic extract whereas zones of 7-18mm indiameter were observed using wax extract for bacterial strains. For fungal strains range of inhibition zones by using methanolic extract were 10-20mm in diameter and 8-15mm in diameter with wax extract. In case of anti-diabetic potential, acarbose was used as standard to inhibit the activity of alpha-amylase enzyme. Using different concentrations of P. hysterophorus extracts, inhibition percentage was observed. For methanolic and wax extracts, the inhibition ranges from 26.02% to 76.20% and 22.08 to 73.85% respectively. These inhibitions were closely associated with that of acarbose inhibition percentage ranged from 33.00% to 82.20%. It is concluded that P. hysterophorus methanolic extract exhibited highest anti-microbial and anti-diabetic potential compared to its wax extract and this potential increased as the concentration of extracts increased. However, Zones of inhibition and percentage of inhibition were less than standard drugs.
Synthesis, Spectral Characterization and Photocatalytic Application of S-doped g-C3N4 Nanocomposites with zno and Cu-doped zno Nanostructure
(UMT, Lhr, 2018) Salma Asif
Investigation of the doping influence on structures and photocatalytic properties of ZnO nanostructures at optimum concentration is presented. Moreover enhanced photocatalytic performance making composite with sulfur doped g-C₃N₄ is also presented. Copper (Cu) is used as dopant on ZnO nanostructures. Undoped and doped (1, 3, 4 and 5 %) doped nanoparticles were prepared by wet chemical method and annealing was done at 450 ᵒC for 3 hours. Sulfur doped graphitic carbon nitride nanosample was prepared by using thiourea. Nanocomposites of sulfur doped graphitic carbon nitride with pure zinc oxide and copper doped zinc oxide were prepared. Two types of composites were prepared. (a) Composites of pure ZnO with graphitic carbon nitride. (b) Composite of copper doped ZnO with graphitic carbon nitride. Different characterization techniques were used to analyze the structural properties like (SEM) scanning electron microscopy, (XRD) X-ray diffraction and FTIR spectroscopy. Photocatalytic activities of all the samples were checked by UV- Visible spectrophotometer. Methylene blue (MB) was employed as an organic pollutant for the photocatalytic activities and mercury lamp was used for irradiation of visible light. All the samples showed a good photodegradation of methylene blue. Cu-4 % doped ZnO was very good sample among all dopant concentrations. ZnO composites with g-C₃N₄ and Cu 4 % doped ZnO nanocomposites with g-C₃N₄ showed considerable degradation.
Synthesis, characterization and photocatalytic applications of p(aac) microgels and its composites of ag doped cuo nanoparticles
(UMT, Lhr, 2018) MADIHA AHMAD
CuO and Ag doped CuO nanoparticles were synthesized through co-precipitation method. Copper sulphate pentahydrate was used as Cu precursor to synthesized CuO nanopaticles. Microgels was synthesized through poly(Acrylic acid)-co-MBA in organic solvent and nitrogen atmosphere. Photocatalytic activity of CuO nanoparticles, Ag doped CuO nanoparticles, microgels and composite were studied. XRD technique was used to verify the size of CuO, Ag doped CuO nanoparticles microgels and composite. TEM, SEM, XRD, FTIR and UV techniques were also used to study the structure and morphology of the CuO nanoparticles, Ag doped CuO nanoparticles, microgels and composites of microgels with Ag doped CuO nanoparticles. FTIR technique was used to determine the functional group and impurities in sample. UV-Vis spectroscopy was used to measure the photocatalytic study of the composite. SEM and TEM techniques were used to determine the image of nanoparticles. The size range of CuO nanoparticles were 15-30nm, Ag doped CuO nanoparticles size range were 25-40nm, microgels and the composite of microgels with Ag doped CuO size were less than 200-300nm. Photocatalytic activity of the synthesized nanomaterials was successfully tested for photodegradation of methylene blue as model pollutant. The photocatalytic activity results confirm that the synthesized composite photocatalyst show higher activity than the individual particles.

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