Carbon , Hydrogen And Nitrogen Research Articles

High-Temperature Rheological Properties and Storage Stability of Bitumen Modified with the Char Produced from Co-Pyrolysis of Different Wastes

By enhancing the bitumen properties with the additives produced from waste, not only can the performance of flexible pavements be improved, but it can also contribute to the environment. This research aims to produce a novel pyrolytic char from different wastes and to investigate the usability of this char as an additive in bitumen. In this study, first, the pyrolytic char was produced from the co-pyrolysis of three different wastes, including waste paper cups, polypropylene (PP), and polyethylene terephthalate (PET) waste. Properties of the char were determined by using CHN (carbon, hydrogen, and nitrogen) and Fourier transform infrared spectroscopy (FTIR) analyses. The high-temperature rheological properties of binders were evaluated by using DSR (dynamic shear rheometer), RV (rotational viscometer), softening point, and penetration tests. Additionally, specific gravity, storage stability, high-temperature performance grades (PGs), and temperature susceptibilities of binders were determined. Test results showed that this pyrolytic char enhanced the high-temperature properties of neat bitumen by increasing softening point, viscosity, rutting resistance, and high-temperature PG of pure bitumen. Additionally, it can be said that the bituminous binder modified with this pyrolytic char had good storage stability when it was used at an 8% ratio in neat bitumen.

SYNTHESIS, CHARACTERIZATION OF COPPER(II) COMPLEX WITH TETRADENTATE N2O2 AND POTENTIAL CONTRIBUTION AS PROMISING ANTIBACTERIAL STUDIES

A square planar Schiff base complex, Cu(H2L) namely N,N’-bis(4-methyl-α-salicylidene)propane-1,3-diaminecopper(II) through the condensation reaction of ligand with copper(II) acetate in the molar ratio of 1:1 in acetonitrile solvent was successfully synthesized. The obtained complex was characterized using, elemental analysis of carbon, hydrogen and nitrogen (CHN), Fourier Transform Infrared spectroscopy (FTIR) and electronic spectra of ultraviolet-visible (UV-vis) spectroscopy. FTIR confirmed the coordinates the metal ion to form mononuclear complex via tetradentate (ONNO) atoms of the phenolic group and azomethine group, respectively. The antibacterial studies of H2L and its Cu(H2L) were determined by screening the compounds against selected various Gram (+) and Gram (-) bacterial strains such as Staphylococcus epidermidis, Bacillus subtilis, Staphylococcus aureus, Vibrio cholera, Enterobacter cloacae and Escherichia coli. Indeed, preliminary results exhibited Cu(H2L) more active than the free ligand and displayed promising antibacterial activity, while no effect has been observed on strains for H2L.

A real time integrated approach for the treatment of petroleum industry oily waste through ancillary carbon metabolism and biocatalytic cascade induction

Recalcitrant hydrocarbons contamination by petroleum oil sludge (POS) disposal from the petroleum refining industry is a major environmental issue. Insufficient biomolecules (biosurfactant and degradative enzymes) production and passive metabolic transformation lead to more prolonged and incomplete bioremediation process. Herein, integration of ancillary carbon metabolism and biocatalytic cascade induction facilitated faster microbial growth, increased supply of precursors for macromolecule production and activated enzymatic degradation cascade. The agricultural by-product, rice husk found to be the suitable ancillary carbon source and elemental analysis of Carbon, Hydrogen and Nitrogen (CHN), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy analyses confirmed the microbial assimilation of the co-substrate. Divalent metal cations such as Cu2+, Fe2+ and Zn2+ were screened as essential enzyme activators, thereby induce the enzymatic degradation of POS. The integrative system exhibited the maximum aliphatic and aromatic hydrocarbons degradation of 96% and 92% during semi-pilot scale treatment (1 Kg of POS). Further, the functional annotation of the genome using Carbohydrate-active enzymes (CAZymes) provided specific insight into the genomic potential of E.xiangfangensis STP-3 in the concomitant metabolism of complex carbohydrates towards the enhanced enzymatic degradation of POS. These findings demonstrated that integrating ancillary metabolism and biomolecular machinery induction provides a sustainable POS clean-up strategy.

Fire Retardancy and Dielectric Strength of Cyclotriphosphazene Compounds with Schiff Base and Ester Linking Units Attached to the Electron-Withdrawing Side Arm.

A series of compounds with Schiff base and ester linking units attached to the electron-withdrawing side arm (Cl, NO2, and OH) have been successfully synthesized through four schemes of the chemical route. These compounds were characterized using Fourier Transform Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance spectroscopy (NMR), and Carbon, Hydrogen and Nitrogen (CHN) elemental analysis. The epoxy resin was used as a matrix of molding to observe the refinement of fire-retardant properties of the modified cyclotriphosphazene compounds. The fire-retardant testing was done using Limiting Oxygen Index (LOI). The LOI value of pure epoxy resin was increased from 22.75% to 24.71% when incorporated with 1 wt.% of hexasubstituted cyclotriphosphazene (HCCP). Interestingly, all the final compounds gave a positive increment in the LOI value and the highest LOI value was obtained from the compound containing a nitro side arm with LOI value of 26.90%. In order to understand the thermal stability of these compounds, Thermogravimetric Analysis (TGA) was carried out. The compound with the nitro group at the terminal end has the highest char residue which is 34.2% at 700 °C. This indicated that the presence of the nitro withdrawing group was able to enhance the fire retardancy of the materials. Based on SEM observation, the shape of the final compound’s char residue demonstrated the formation of a porous protective layer with a dense surface. The dielectric property was conducted according to ASTM D149 AC breakdown voltage to determine its dielectric strength. The results showed that the highest dielectric strength value belonged to the compound containing a nitro group side arm with 24.41 kV/mm−1 due to the π electron delocalization.

Inhibition Effect of Gold (III) Theophylline Nano-complex on ALT Enzyme Activity in Human Serumof Iraqi Patients with Liver Disease

Introduction: The ultrasonic sonication approach was used to create an Au(III) nano complex with theophylline. Methods: To explore and suggest the structure of the nano complex, UV-Vis spectroscopy, Fourier transform infrared (FT-IR), and carbon hydrogen and nitrogen (CHN) elemental studies were used. The FE-SEM was used to prove the nanoscale of the prepared complex and was to be less than 20 nm. The effect of the gold nano complex (Au (THP)2(Cl)2) on alanine transaminase (ALT) activity in the serum of chronic liver disease patients was investigated. Results: Compared to the control group, the patients with chronic liver disease with and without nano complex had a significant rise in serum levels of ALT activity (P < 0.001). Furthermore, in individuals with chronic liver disease who received nano complex, the blood levels of ALT activity were significantly lower than those who did not receive nano complex. The reason is that the Au nano complex aggressively interacts with carboxylic groups of important enzymes and inactivates them; further, the Au nano complex had an inhibitory effect on serum ALT activity.

Microstructure and mechanical properties of AlCoCrNiTi–C High Entropy Alloy processed through Spark Plasma Sintering

AlCoCrNiTi–C High Entropy Alloy (HEA) fabricated through mechanical alloying (10 h) and Spark Plasma Sintering (SPS) at 1000 °C develops a mixture of NiAl B2 phase, Cr rich phase and fine TiCs. Transmission Electron Microscope (TEM) images before and after milling confirms the presence of BCC phases in the alloy. Carbon Hydrogen and Nitrogen (CHN) analysis reveal the presence of carbon content in milled powders after 10 h. Back Scattered Electron (BSE) images and elemental mapping indicates the presence of TiCs along grain boundaries of NiAl B2 phase. Microstructural characterization before and after heat treatments reveals the fact that there is an increase in the volume fraction of Cr rich phase. Moreover the alloy develops a good room temperature compressive strength of 2750 ± 4.3 MPa, high temperature strength of 871 ± 3.1 MPa at 800 °C along with micro hardness of 860 ± 7.8 HV 0.5 . Nano indentation results shows that the major contribution to hardness and strength comes from NiAl phase which has a value of 10.2 ± 2.1 GPa. Enhanced properties of the alloy can be attributed to the presence of NiAl B2, disordered Cr rich BCC phase along with fine TiCs. • Composite microstructure resulting from in situ reactions. • Enhanced strength due to grain boundary strengthening and precipitation hardening. • Limited grain growth at temperatures of 800 °C, 900 °C and 1000 °C. • Heat treatment studies reveals increase in volume fraction of Cr rich phase.

Preparation, luminescence and photofunctional performances of a hybrid layered gadolinium-europium hydroxide

The design and fabrication of rare earth ions incorporated into the inorganic/organic hybrid materials have attracted growing attention for seeking improved optical properties and photofunctional performances. In this paper, a novel hybrid composite based on the layered rare earth hydroxides was successfully prepared by the ion-exchange and intercalation chemical process. The rare earth elements in the composite contain gadolinium (Gd) and europium (Eu) and the molar ratio of Gd to Eu is kept constant at 1.9 : 0.1. Organic sodium dodecyl sulfonate and dye coumarin-3-carboxyllc acid are simultaneously incorporated into the layered rare earth hydroxides as supporting agent and light-harvesting antenna, respectively. The resulting hybrid layered rare earth hydroxides exhibit the enlarged interlayer distance with about 2.60 nm, and the chemical composition was confirmed through X-ray diffraction, carbon, hydrogen and nitrogen (CHN) elemental analysis, infrared spectroscopy, and thermogravimetric analysis. The layered solid compound shows the characteristic red emission corresponding to the 5D0→7F2 transition of Eu3+ ion, and the luminescence intensity of the optimized compound is greatly enhanced as compared to its corresponding nitrate and the hybrid composite without the introduction of dye molecule. The hybrid layered rare earth hydroxides can be exfoliated into bright colloidal solution, which show superior recognition capability to Cu2+ ion with the distinct luminescence quenching. The large quenching constant (1.4 × 104 L/mol) and low detection limit (0.35 μmol/L) are achieved for Cu2+ ion, implying a “turn-off” fluorescent sensor for Cu2+ detection. Moreover, a transparent film was prepared based on the colloidal solution and displays the typical red emission in folded shape. The new hybrid compound with enhanced luminescence and excellent photofunctional performances is expected to be applied in the fields of fluorescent sensing and flexible optical devices.

Synthesis and Antimicrobial Evaluation of Some New Organic Tellurium Compounds Based on Pyrazole Derivatives.

A novel series of organic tellurium compounds based on pyrazole derivatives with a general formula of ArTeBr3 and Ar2TeBr2 [Ar = 2-(3-(4-substituted phenyl) -5-(2-chlorophenyl)-1H-pyrazol-1-yl)-3,5-dinitrophenyl] were obtained by the refluxing of corresponding aryl mercuric chlorides with TeBr4 in two different mole ratio of 1:1 and 2:1, respectively, in free-moisture dioxane solvent under an argon atmosphere. Compounds of ArTeBr3 and Ar2TeBr2 were reduced by the action of ethanolic solution of hydrazine hydrate obtained Ar2Te2 and Ar2Te, respectively. Reaction of Ar2Te2 with excess thionyl chloride or iodine gave the corresponding trihalides ArTeCl3 and ArTeI3, respectively while the reaction of Ar2Te with thionyl chloride or iodine gave the corresponding Ar2TeCl3 and Ar2TeI3, respectively. The structures were elucidated according to their elemental analysis of carbon, hydrogen and nitrogen (CHN) and some of the spectroscopic techniques such as infrared IR and nuclear magnetic resonance for 1H and 13C. The antimicrobial activity for all the synthetic compounds were assayed against both Gram-negative and Gram-positive bacteria by using the agar diffusion method. The tellurated pyrazole derivatives showed a good degree against bacteria growth. In some cases, the antimicrobial activities of the synthetic compounds were better than amoxicillin.

One‐pot synthesis of 1,4‐dihydropyridines and N‐arylquinolines in the presence of copper complex stabilized on MnFe2O4 (MFO) as a novel organic–inorganic hybrid material and magnetically retrievable catalyst

In this work, the design and synthesis of a heterogeneous catalyst based on functionalization of manganese ferrite nanoparticles encapsulated in a silica layer with Schiff base and subsequent incorporation of copper is presented. The fabricated hybrid material was characterized by employing Fourier‐transform infrared spectroscopy, X‐ray powder diffraction, field emission scanning electron microscopy, transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, differential thermal gravimetric analysis, vibrating sample magnetometry and inductively coupled plasma‐optical emission spectrometry techniques. The prepared organic–inorganic hybrid material was successfully used as an efficient and recoverable catalyst for the synthesis of 1,4‐dihydropyridines and N‐arylquinolines under mild and green reaction conditions. The results showed that the catalyst exhibited excellent catalytic activity under optimum reaction conditions and the desired products were obtained in good to excellent yields. The new 1,4‐dihydropyridines and N‐arylquinolines were characterized by Fourier‐transform infrared spectroscopy, 1H NMR and Elemental analysis of Carbon, Hydrogen and Nitrogen (CHN) analyses. Study of the catalyst reusability confirmed that the catalyst could be recycled for five reaction runs with slight loss of the catalytic activity and negligible copper leaching.

A PRELIMINARY STUDY ON DETECTION OF CADMIUM (II) ION USING BENZOYL PHENYLTHIOUREA

Two benzoyl phenylthiourea derivatives namely: 1-benzoyl-3-(4-bromophenyl)-2- thiourea (M) and 1-(4-chlorobenzoyl)-3-(4-methylphenyl)-2-thiourea (MI) were successfully synthesized and characterized by using Carbon, Hydrogen and Nitrogen (CHN) micro elemental analysis, Fourier Transform Infra-Red (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy methods. Elemental analysis for M (C14H11N2SOBr) and MI (C15H13N2SOCl) were compatible with the expected theoretical calculation. The FTIR spectrum obtained for M and MI compounds show the presence of four important functional groups; ʋ(N-H), ʋ(C=O), ʋ(C-N) and ʋ(C=S) that appeared at 3380-3367 cm-1, 1666-1681 cm-1, 1342-1268 cm-1 and 1146-1152 cm-1, respectively. The NMR spectrum data for MI shows the chemical shift at 6.63-7.85 ppm for Ar-H group, 2.26-2.40 ppm for methyl group, 7.44 ppm for N1H and 3.09 ppm for N2H. For the application, M and MI were used as probes in detecting Cd2+ in methanol solution. UV-Visible spectrophotometer was used to analyze the absorbance values of the compound before and after Cd2+ was added. It is found that compound M displayed the behavior of ‘turn off’ sensors while compound MI possessed the behavior of ‘turn on’ when detecting 0.5×10-5 M and 1×10- 5 M of Cd2+ ion. The behavior of ‘turn on’ and ‘turn off’ is due to the increasing or decreasing of absorbance when Cd2+ was added to the compounds.

Preparation, micro-structure and mechanical properties of porous carbonate apatite using chicken bone as raw material

Introduction: The increasing in bone loss due to trauma disease or accident leads to the demand for bone substitute materials. Autograft is the gold standard for bone graft; however, it has limited supplies and additional surgery for harvesting. Therefore, the artificial bone graft is necessary for bone defect treatment. One of the potential candidates for bone repair and regeneration is porous Carbonate Apatite (CO3Ap) due to its excellent biodegradability and biocompatibility. Understanding the importance of recycling of waste materials and by-products from the food industry such as poultry bone could be used as the alternative source for starting material. Thus, recycling and adding value for the food waste could be done with the development of artificial bone graft.
 Method: In this study, porous CO3Ap was prepared using bio apatite powder derived from chicken bone via the sacrificial template technique. Templates such as chopped cotton fibers were used to make porous CO3Ap with interconnecting pores. X-ray diffraction (XRD) and Scanning electron microscope (SEM) were used to characterize phase composition and structure. Carbonate content was evaluated using elemental analysis CHN (carbon hydrogen and nitrogen) analyzer.
 Results: The results indicated that a pure CO3Ap block consisting of elongating pores could be obtained. Mechanical strength was evaluated in terms of Diametral Tensile Strength (DTS). Porous CO3Ap had a mean DTS value of 198.5 +/- 12.9 kPa and an average porosity of approximately 70%.
 Conclusion: As a conclusion, CO3Ap containing 5.25 ± 0.03 % wt of carbonate with low crystallinity and the inter-connecting porous structure is advantageous on bone regeneration as being a useful material for application to repair the bone defect.

Efficient Hg(II) ionic probe development based on one-step synthesized diethyl thieno[2,3-b]thiophene-2,5-dicarboxylate (DETTDC2) onto glassy carbon electrode

In this approach, diethyl thieno [2,3-b] thiophene-2,5-dicarboxylate-2 (DETTDC2) was prepared in one-pot synthesis by using pentan-2,4‑dione (P24D), carbon disulfide, and ethyl bromoacetate (EBA) precursors and finally the characterization was carried out systematically with proton-Nuclear Magnetic Resonance (HNMR), Impedance spectroscopy (EIS), Fourier-transform infrared spectroscopy (FTIR) and carbon hydrogen and nitrogen (CHN) analyzer. An ultra-thin sheet of DETTDC2 was retained on a glassy carbon electrode (GCE) with managing binder to evolve the expected working electrode of Hg(II) cationic sensors. The calibration plot was determined based on the current vs. amount of Hg(II) ion and the final calibration curve was appeared to be linear (r2: 0.9979) over the low to high range (LDR: 0.1 nM ∼ 0.01 M). The sensor performance in term of sensitivity (0.74367 µA µM−1 cm−2) was predicted from the slope of calibration plot. It was also measured the detection limit (DL: 12.80 ± 0.64 pM) of the sensor at signal to noise ratio of 3. This sensor was applied to sensitive detection of Hg(II) ions in phosphate buffer condition. Therefore, this novel electrochemical approach is the suitable method for designing the toxic heavy-metal detection to safe-guard the public health and environment remediation.

Photocatalytic activity under visible light irradiation of cement based materials containing TiO2-xNy nanoparticles

Self-cleaning activity of Portland cement pastes blended with nanoparticles of titanium oxynitride (TiO2−xNy) was studied. Samples with various amounts of TiO2−xNy (1% and 3%) were evaluated under irradiation of UV and visible light, and with two curing ages (65 hour and 28 days). Rhodamine B was the pigment used and its loss of color on the cement pastes was carried out using a Spectrometer UV/Vis measuring the coordinates CIE (Commission Internationale de l’Eclairage) L∗, a∗, b∗. Discoloration of Rhodamine B on the surface of the samples was established as the photocatalytic efficiency coefficient (ε). In addition, samples with TiO2 nanoparticles (1% and 3%) were studied under the same conditions and their performances were compared with TiO2-xNy. The presence of nitrogen in the tetragonal structure of TiO2 was evidenced by X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectrophotometry and Carbon, Hydrogen and Nitrogen (CHN) analysis. The band gap for TiO2 and TiO2-xNy was determined by the transformed Kubelka-Munk function ( [F (R∞) hv]1/2). The results have shown a similar behavior for both additions under UV light irradiation, with 3% being the addition with the highest photocatalytic efficiency obtained in the early ages of curing time. TiO2−xNy showed activity under irradiation with visible light, unlike TiO2, which could only be activated under UV light. At the late curing ages, the samples with 3% of TiO2-xNy showed the highest efficiency under irradiation of UV and visible light.

Biosynthesized gold nanoparticles supported on magnetic chitosan matrix as catalyst for reduction of 4-nitrophenol

The design and environmentally-safe synthesis of magnetically recoverable solid-supported metal nanoparticles with remarkable stability and catalytic performance has significant industrial importance. In the present study, we have developed an inexpensive bioinspired approach for assembling gold nanoparticles (AuNPs) in magnetic chitosan network under green, mild and scalable condition. AuNPs were well loaded on the surface of the magnetic support due to the presence of hydroxyl (-OH) and amino (-NH2) groups in chitosan molecules that provided the driving force for the complexation reaction with the Au(III) ions. Reduction of the Au(III) to Au(0) is achieved by using Melicope ptelefolia aqueous leaf extract. The synthesized magnetic chitosan supported biosynthesized Au nanocatalyst was characterized using Fourier Transform Infrared (FT-IR), Carbon, Hydrogen and Nitrogen (CHN), Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD) and Atomic Absorption Spectroscopy (AAS) analyses. FTIR spectrum of magnetic chitosan shows peaks at 1570 cm-1 indicative of N-H bending vibration and at 577 cm-1 which designates the Fe-O bond. CHN analytical data further supported the coating of chitosan onto the magnetite. TEM analysis shows an amorphous layer around the magnetite core which supported the coating of chitosan on the magnetite surface and the average particle size of AuNPs calculated was 7.34 ± 2.19 nm. XRD analysis shows six characteristics peaks for magnetite corresponding to lattice planes (220), (311), (400), (422), (511) and (440) in both the magnetite and magnetic chitosan samples (JCPDS file, PDF No. 65-3107). Meanwhile, XRD analysis of catalyst shows characteristic peaks of AuNPs at 2q (38.21°, 44.38°, 62.2°, 77.32° and 80.76°) are corresponding to (111), (200), (220), (311) and (222) lattice plane (JCPDS file, PDF No.04-0784). AAS analysis shows the loading of AuNPs as 5.4%. The rate constant achieved for the reduction of 4-nitrophenol to 4-aminophenol in the presence of hydrazine hydrate using 10 mg of catalyst is 0.0046 s-1. The magnetic chitosan supported AuNPs is effective as catalyst for the reduction of 4-nitrophenol.

Structural, spectral, thermal and nonlinear optical analysis of 4-fluoro salicylideneaniline crystal

4-fluoro salicylideneaniline (4FSA) (IUPAC Name: 4-Fluoro-2-[(phenylimino)methyl]phenol) crystals were grown by condensation reaction. The lattice constants and crystal system were determined from X-ray diffraction (XRD) analysis. 4FSA crystallizes in monoclinic centrosymmetric space group P21/c. The chemical composition of 4FSA was confirmed by carbon, hydrogen and nitrogen (CHN) elemental study. The vibrational frequencies of the crystal were identified by Infrared and Raman spectra. NMR spectroscopy was employed to ascertain the molecular structure. Thermogravimetric (TG) / Differential scanning calorimetry (DSC) analysis reveals that 4FSA is melting at 75 °C. The region of optical transmission of 4FSA has been studied by UV–Vis–NIR spectroscopy. The nonlinear refractive index (n2), nonlinear absorption coefficient (β) and the third-order nonlinear optical (NLO) susceptibility (χ(3)) were calculated by Z-scan analysis.

Synthesis and characterization of exfoliated biochar from four agricultural feedstock.

Highly porous biochar (BC) structures have been prepared from inexpensive biomasses like rice straw, bamboo, sugarcane waste, and corn cob via a slow pyrolysis technique in nitrogenous atmosphere. A surface engineering technique has been applied to enhance the surface-to-volume ratio of each biochar sample and finally compared its characteristics through standard surface and elemental characterization techniques, viz. CHN (carbon, hydrogen, and nitrogen), FTIR (Fourier transform infrared spectroscopy), BET (Brunauer-Emmett-Teller), and SEM (scanning electron microscopy). All the biochar samples were observed to be highly carbonized and aromatized. Exfoliated structures were found to contain more elemental carbon (34.14-77.32%) than its native form (30.92-74.46%). Aromatic hydrocarbon, aromatic C=C, aromatics, aliphatic C-O, aliphatic hydrocarbon, and H-bonded OH groups were found to predominate in the surface of biochar structures independent of their precursor composition and extent of exfoliation. SEM micrographic images clearly ensured about the unoriented sheets like the morphology of different biochar samples. Although no significant structural difference was found to exist depending on their precursor compositions, quantitative enhancement of porosity was found to be observed after exfoliation. Both native (240.65m2/g) and exfoliated (712.89m2/g) biochars derived from sugarcane wastes were observed to have a maximum surface area in comparison to the biochars derived from rice straw (native, 22.08m2/g; exfoliated, 29.92m2/g), bamboo (native, 42.08m2/g; exfoliated, 248.38m2/g), and corn cob (native, 136.62m2/g; exfoliated, 221.71m2/g). Exfoliated biochars were found to be consistently more potent in comparison to its native form as per our comparative characterizations performed so far.

Nano MgO catalyst for chemical depolymerization of polyethylene terephthalate (PET)

This paper focuses firstly on the production of monomers bis (2-hydroxyethyl) terephthalate (BHET) and oligomers by using two different form of MgO light active and Nano Magnesium oxide with different weight ratio (0.15, 0.25 and 0.5) by using chemical recycling glass condenser at 190 ˚C. The second purpose is to study the effect of catalyst ratio, time of reaction and yield of products of the product. Elemental analysis for Carbon –Hydrogen and Nitrogen (CHN), differential scanning calorimetry (DSC), infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) have been investigated. Results indicated the catalytic activity was found to correlate with surface area; however, LA MgO has shown an exceptional activity, still it is higher than Nano MgO in order to reduce the reaction time till 30 minutes instead of 7 hours without catalyst. The analysis of the thermograms has indicated the presence of various kinds of monomer, dimer and oligomers that are formed during the recycling; this is particularly evident due to new peaks indicating the formation of BHET monomer and oligomer of lower molecular masses.

Cogon Grass for Oil Sorption: Characterization and Sorption Studies

Cogon grass (Imperata cylindrica), an invasive, unwanted grass was used and evaluated for its applicability for the sorption of engine oil. Other than dried and ground for smaller size, no notable treatment was performed on the cogon grass. The physical and chemical properties of cogon grass were characterized by ash content, bulk density, pH slurry, and Field Emission Scanning Electron Microscopy (FESEM). The oil sorption was performed in a batch adsorption system. The effects of contact time, dosage of adsorbent and oil retention were investigated. The bulk density and ash content of the prepared carbon was 0.34 g/ml and 7.80 %, respectively. The pH slurry value was near neutrality (6.48). FESEM micrograph of cogon grass showed jagged and rough surface. FTIR spectra revealed the presence of aromatic rings of lignin and some aromatic compounds associated with CH. Carbon, hydrogen and nitrogen (CHN) analysis revealed that 41% of cogon grass consists of carbon. The cogon grass was observed to wet oil almost instantly with sorption equilibrium time of 5 min. The dose of cogon grass was found to slightly affect the sorption capacity. Oil retention experiments reveal the good ability of cogon grass to hold oil with about 96% retention after 24 h dripping. This study may provide an insight on the usefulness of cogon grass for removal of engine oils.

Novel route for amine grafting to chitosan electrospun nanofibers membrane for the removal of copper and lead ions from aqueous medium

A novel step wise synthetic route was developed to prepare amine grafted nanofibers (AGNFs) affinity membrane. The chemical structure of the nanofibers (NFs) after grafting was studied by acquiring Fourier Transform Infrared (FT-IR) spectra and Carbon, Hydrogen and Nitrogen (CHN) data. The morphology of the NFs before and after grafting was studied by Field Emission Scanning Electron Microscope (FE-SEM). FT-IR and CHN data confirmed the introduction of new functional groups into the primary structure of chitosan (CH). FE-SEM showed denser membrane with no deterioration of the NFs morphology after grafting. The aqueous stability of the membranes was studied in distilled water. The AGNFs membranes showed good aqueous stabilities (with only ∼ 6% loss in weight until 24 h and remained stable thereafter) which was less than the weight loss by glutaraldehyde treated nanofibers (GNFs) (∼44% loss in weight until 24 h) and pristine NFs (100% loss in weight as soon as the NFs were immersed in distilled water). The maximum adsorption (qm) capacity of AGNFs for Cu (II) and Pb (II) was observed to be 166.67 mg.g−1 and 94.34 mg.g−1. The adsorption capacity of the present systems was much higher for Cu (II) when compared to the already existing conventional and chitosan adsorbents. This increased might be related not just to the size, but more potentially to the increase in the number of nitrogen binding sites (chelating sites). Nitrogen donates lone-pair of electrons for chelation. The combination of processing into nano size and amine grafting (AG) has significantly increased the adsorption capacity of CH NFs membrane.

Synthesis and photoluminescence properties of europium(III) complexes sensitized with β-diketonato and N, N-donors ancillary ligands

Synthesis of three new europium(III) complexes with 1,3-[bis(4-methoxyphenyl)]propane-1,3-dionato (HBMPD) ligand and ancillary ligands such as 2,2′-biquinoline (biq) or neocuproine (neo) has been reported in this report. The synthesized complexes were characterized by IR (infrared), 1H and 13C NMR (nuclear magnetic resonance) spectroscopy, CHN (carbon, hydrogen and nitrogen) elemental analysis, XRD (X-ray diffraction), TGA (thermogravimetric analysis) and photoluminescence (PL) spectroscopy. The emission spectra of europium(III) complexes displayed both the low intensity 5D1–3→7F0–3 transitions in 410–560nm blue-green region and high intensity characteristic 5D0→7F0–3 transitions in 575–640nm orange-red region correspond to the emission of ancillary ligands and europium ion respectively, which can lead to white luminescence due to integration of blue, green and red color emissions. The photoluminescence investigations indicate that the absorbed energy of the HBMPD ligand transferred to the central europium(III) ion in an efficient manner, which clearly explained by antenna effect. The excellent results of thermal behavior and photophysical properties like luminescence spectra, CIE (Commission Internationale Eclairage) chromaticity coordinates, luminescence decay curves and high quantum efficiency of the complexes make them a promising component of the white light-emitting diodes in display devices.