Study of Mechno- luminescence, thermoluminescence properties of solid state reaction derived Ce3+co-doped Ca2MgSi2O7:Eu2+ microphosphors and application for mechnoluminescent display device technology.
In this paper, we discuss a series of ce3+ co doped di calcium magnesium di silicate phosphors were synthesized by high temperature solid state reaction method. Thermoluminescence properties of prepared sample also investigated. Their kinetic parameters [activation energy (E), frequency factor (s) and order of the kinetics (b)] of these phosphors were evaluated and compared using the peak shape method. FractoMechno- luminescence properties Ca2MgSi2O7: Eu2+ and Ca2MgSi2O7: Ce3+, Eu2+ phosphors. Their ML properties showed that when Ca2MgSi2O7: Eu2+ phosphor is co doped with Ce3+, ML intensity was more (strongly) enhanced and their mechanoluminescence intensities of Ca2MgSi2O7: Eu2+ and Ca2MgSi2O7: Eu2+, Ce3+ phosphors increased proportionally increased with the increase in impact velocity, which suggests that these phosphors can be used as mechnoluminescent display device such as fracture sensor, impact sensor, damage sensors, safety management monitoring system etc .
The beginning of industrialization human being has observed a variety of environmental concerns on the earth. The industrialization has not simply carried growth and affluence but finally troubled the environment. One of the crashes is noticeable, in form of water pollution. Now the present study of heavy metal pollution of water body has been talk over. Effluents from an unlimited amount of industries viz., textile, tannery, dyes, pigment, paint, wood processing, electroplating, leather, petroleum refining etc., have a key amount of heavy metal in their wastewater. The conventional technique of treatment heavy metal contamination contains chemical precipitation, membrane separation, chemical oxidation, ion exchange, electro dialysis, reverse osmosis, etc. These procedures are costly, energy intensive and often linked with creation of toxic by-product. Hence, the adsorption has been experimental as a cost-efficient method for treatment of heavy metals removal from wastewater. In the existing study numerous inexpensive adsorbent has been an analysis as a reduction of heavy metal effluence from wastewater. These adsorbent include resources of natural origin similar to zeolites, peat moss, peat moss, chitin, clay are find to be a real agent for elimination of lethal heavy metal like Cu, Ni, Hg, Zn, Cr , Pb, Cd, etc. Distinctly from these, a range of farming wastes like waste tea, rice husk, black gram neem bark, walnut shell, etc. Also known to be an influential adsorbent for the eliminating heavy metal from wastewater. at the side of that inexpensive or low-cost manufacturing byproduct like lignin, fly ash, iron (III) red mud, hydroxide and coffee husks, tea factory waste, Areca waste, sugar beet battery industry waste, pulp, waste slurry, blast furnace sludge, grape stalk wastes, sea nodule residues have been found for their methodological option for removal toxic metal from waste water.
Natural fibers are becoming a competitive option as reinforcement of polymeric composite materials due to their bio-based character, good specific mechanical properties, low cost and inexhaustible supply. The aim of this study was to make the Bamboo fiber and high density polyethylene (HDPE) composite and to measure the wet loss of the composite due to removal of moisture content at 105 0C, 125 0C and 135 0C temperature. Bamboo fiber were extracted from bamboo culm and treated with 0.5 M NaOH. Bamboo fiber-reinforced HDPE composites were prepared employing melt blending technique followed by heat press molding with various weight fractions (5, 10, 30 and 40 wt. %) of the treated bamboo fiber with HDPE. A systematic investigation of the thermal behavior on the moisture content of the composites was carried out. It was observed that at 135 0C temperature more moisture removed from the composite compared to 105 0C and 125 0C temperature. It also revealed that the weight loss of the composite increased with the increase in the Bamboo fiber loading (5% to 40%).
Heavy Metals in Soil and Vegetables Irrigated with Ex- Tin Mining Ponds Water in Barkin – Ladi Local Government Area Plateau State, Nigeria
Tin mining pond water irrigated ﬁelds can cause potential contamination with heavy metals to soil and vegetables, thus pose a threat to human beings. The current study was designed to investigate the contamination of the soil with toxic heavy metals and their accumulation in edible vegetable crops. The heavy metals Pb, Cu, Cd, Zn, Cr, Fe, Mn and As were analyzed for their bioaccumulation factors to provide baseline data regarding environmental safety and the suitability of tin mining pond water for irrigation in the future. The contamination factor (CF) of these metals in the soil were calculated and indicated levels of metal contamination in the order of Cd > Zn > Pb > Cr > Cu > As ˃ Fe ˃ Mn. The concentrations of Pb, Cd, Cr, As, and Mn in the edible vegetables were above the safe limit prescribe by FAO/WHO, 2007 and EU, 2002 in all studied vegetables. The results indicated a potential pathway of human exposure to slow poisoning by heavy metals due to the utilization of vegetables grown on heavy metal contaminated soil that was irrigated with tin mining pond water sources. Amongst the studied vegetables, cabbage was safe from other metal except for As and Cr that were observed to exceeds tolerable limit. The irrigation source was identiﬁed as the source of the soil pollution in this study. Thus, the consumption of these vegetables might poses substantial health risk to consumers for this reason we therefore, emphasizes the need for proper remediation of the wastewater to reduce the health risk and the extent of heavy metals contamination.
The presence of natural organic matter (NOM) in source water has posed many challenges for conventional water treatment facilities. Small organic acids, such as humic acid, present in NOM, have a high potential to influence the performance of water treatment processes. Uncontrolled application of agricultural chemicals leads to the simultaneous presence of toxic substances. In this work, batch adsorption experiments were conducted to examine the biosorption of HA onto chemically activated coffee husk. The biosorption process was studied as a function of operating conditions, such as contact time, pH of the solution, HA concentration, adsorbent dose and agitation speed parameters. Experimental results showed that the adsorption has an equilibrium time of 60 min with a maximum adsorption of 93.7%. The optimum pH for maximum HA adsorption was found to be 5.5, with a maximum adsorption of 94.3%. . As the dose of adsorbent increased from 1 to 25 g/L, the concentration of HA was observed to reduce from 10 to 1.67 mg/L which is below the WHO (World Health Organization) guideline value of 2 mg/L. The amount of HA adsorbed increased with increasing the initial adsorbent concentration from 0.5 to 20 mg/L. The adsorption kinetics well fitted the pseudo-second order model with the correlation coefficient R2 = 0.997 and Ks = 0.078. The experimental sorption equilibrium can be represented by the Langmuir isotherm (R2 = 0.998, SSE = 0.006). An average desorption capacity of 87.3% was observed. The study shows that chemically activated coffee husk can be a potential candidate to be used as a biosorbent in the removal of NOM from aqueous solutions.
Research on waste frying oil based lubricant base stocks production and trimethylolpropane (TMP) was investigated. Quality parameters were tested for the waste frying oil. The hydrolysis process was conducted to extract the free fatty acid from waste frying oil. TMP ester was produced via reaction between free fatty acids of waste frying oil and TMP at 130-140°C, for 5 hours with acid-catalyzed condition. Modification of TMP ester by epoxidation reaction followed by ring-opening reaction using a medium branch chain alcohol; 2-ethylhexanol. The TMP ester was reacted with hydrogen peroxide and formic acid at 45-55°C for 2½ hours during epoxidation process. Epoxidized TMP ester was reacted with 2-ethylhexanol in mol ratio of 1:2 to produce ether ester TMP. Concentrated sulphuric acid was used as a catalyst during ring opening and esterification processes. Ether ester TMP functional groups and chemical structure were identified using FTIR and NMR, respectively. Confirmation with FTIR has indicated sharp peak at 1742 cm-¹, proved the existence of ester group which confirmed the TMP ester formation during esterification and broad peak of 3456 cm-1 during ring opening indicated the formation of ether ester TMP. In ¹H NMR analysis, the signal of methylene proton in which the carbon attached to ether esters TMP existed at 4.0-4.1 ppm and for 13C NMR, the carbonyl ester signals existed in the range of 174.1 ppm. Several analyses were conducted on the ether ester TMP base stock such as hydroxyl value, viscosity value, pour point and flash point. It showed good low temperature behaviour with pour point at -40ºC and high thermal stability, flash point value exceeding 250ºC and viscosity value of 75 cP. The ether ester TMP produced is comparable with a commercial biolubricant in the market respectively.
Synthesis, Characterization and catalytic activity of Palladium-Based Metallodendrimer with Triazine
A novel Pd-based metallodendrimer has been directly prepared by the reaction of substituted triazine with substituted benzoyl chloride in good yields using (Ph3P)2PdCl2 and DMF at 70 oC. This procedure avoids the use of high temperature and severe reaction conditions. The surface morphology like as entangled nanofibers from SEM image and the presence of Palladium ions of the compound from EDX analysis were obtained in addition TG and DSC showed the good thermal stability of the compound. This white solid compound was found to be an effective homogeneous catalyst for the synthesis of ynones in where the synthetic route was copper and phosphine ligand-free.
Chemo-Remediation of Crude Oil Polluted Soils Obtained from Recent Polluted Site in Oil Producing Environs in Rivers State Nigeria
The chemo- remediation of crude oil polluted soils from recent pollution sites in oil producing environs in River state was carried out by both in vivo and in vitro methods using macro-soil nutrients ( Nitrate, Phosphate and Potassium) as index for remediation. The soil samples were labeled A, B, C, D1 to D6, sample A was obtained from pollution free site used as a control. Sample C was crude oil polluted soil not treated with surfactant, sample B was crude oil polluted soil leached with surfactant and not mineralized. Samples D1-D6 were polluted soil samples, leached with surfactant and mineralized with fertilizer. The samples were leached with linear alkyl benzene sulphonate (LABS) and later mineralized with Nitrate, Phosphate and Potassium (N.P.K) fertilizer and returned to the site of excavation to fallow for four months. The samples were later re-excavated and taken to the laboratory for analysis. Nitrate and phosphate contents were obtained with the aid of spectrum lab 725 UV visible spectrophotometer and potassium content was determined by use of a flame photometer. Results showed that sample A had nitrate concentration of 330ppm, sample B had concentration of 21ppm, sample C had a concentration of 54ppm while samples D-D6 had concentrations ranging from300ppm to 420ppm.Similarly, The phosphate concentrations were 68.50ppm, 17.00ppn, 28.00ppm and 48.80-136.40ppm for sample A, B, C.D1-D6 respectively. The potassium concentrations were not different as concentrations of 46ppm, 12ppm, 28ppm and 38ppm-64ppm was recorded for samples A, B, C, and D1-D6 respectively. These results revealed that crude oils not only renders soils unusable but also destroys the nutrient availability in soils. The soils can therefore quickly be reclaimed by leaching them with surfactants and mineralizing them with adequate inorganic fertilizer.
Baeyer-VillThis review covers twenty eight monomeric Pt(η2-P2L)X2 (X = Br or I) derivatives. These complexes exist in cis- as well as trans-configurations from which the complexes with cis-configuration are more common. The organodiphosphines create wide varieties of the metallocyclic rings PNP, PC2P, PC3P, PNCNP and PC4OC4P. The mean values of Pt-L bond distances in cis-complexes are: 2.230 Å (P), 2.490 Å (Br) and 2.240 Å (P) 2.666Å (I), respectively. In the trans-complexes the values are 2.319 Å (P), 2.429 Å (Br) and 2.320 Å (P), 2.615 Å (I). The Pt-X bond distances in the cis- as well as in the trans-derivatives elongate with the covalent radius of the X atom. In addition in the cis-derivatives the Pt-X bond distances are longer than those in trans-derivatives, as a reason of higher trans-influence of P over the respective halogens. Some of the complexes are examples of distortion isomerism. Finally, the structural data of Pt(η2-P2L)X2 (X = Br or I) are compared with the values of Pt(η2-P2L)X2, complex and discussed.
Baeyer-Villager oxidation reaction has become accepted as a right approach in the ring expansions for the preparation of both bicyclic and tricyclic lacotnes; however, successful application of the regioselective Bayer-Villager oxidation protocol to the synthesis of particularly congested scaffolds remains distinctly tricky. Herein the Baeyer–Villiger oxidation of Bicyclo[3.2.0]hept-3-ene-6-one is studied with oxygen insertion leading to the functionalized oxabicyclic adduct with complete regioselectivity.