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The cupric oxide (CuO) loaded graphitic carbon nitride (g-C

The radiolytic stability of aqueous solutions containing two different bis-1,2,4-triazines was studied under static gamma irradiation. Sulphophenyl derivatives of bis-1,2,4- triazinyl pyridine (SO3-Ph-BTP) and bis-1,2,4-triazinylbipyridine (SO3-Ph-BTBP) were dissolved in 0.1 M and 1 M HNO3 solutions and the impact of gamma irradiation was assessed by the measurement of distribution ratios of Am(III) and Eu(III) using irradiated samples. The results were compared for two different organic solvents containing N,N,N’,N’-tetraoctyldiglycolamide (TODGA) or N,N-didodecyl-N’,N’-dioctyldiglycolamide (D3DODGA). The separation efficiency of all the systems remained unchanged when the absorbed dose was 100 kGy, and gradually decreased at 200 kGy and 500 kGy. The radiolytic degradation was more apparent for SO3-Ph-BTBP in comparison to SO3-Ph-BTP at higher acidity. The degradation of sulphonate groups in the molecules was evidenced in ATR-FTIR spectral studies.

Selectivity between Am3+ and Cm3+ was investigated after their aqueous complexation with three structurally tailored hydrophilic bis-(1,2,4-triazin-3-yl) ligands followed by their extraction with N,N,N′N′-tetraoctyl diglycolamide (TODGA) dissolved in an ionic liquid (C4mim·Tf2N). The three hydrophilic ligands used were SO3PhBTP, SO3PhBTBP, and SO3PhBTPhen. It was evident from the solvent extraction studies that SO3PhBTP formed a stronger complex with Cm3+ than with Am3+, but SO3PhBTPhen showed better complexation ability for Am3+ than for Cm3+, and SO3PhBTBP showed no selectivity for the two actinide ions. DFT calculations indicated that the coordinating ‘N’ atoms in BTP were more co-planar in the complex and this co-planarity was higher in the Cm3+ complex as compared to that in Am3+. In the case of BTBP and BTPhen ligands, on the other hand, the co-planarity was more pronounced in the Am3+ complexes. Mayer's bond order calculations of M–N bonds in the complexes also indicated a reversal of the complexation ability of the BTP and BTPhen ligands for Am3+ and Cm3+. Calculations of the complexation energies further supported the higher selectivity of the BTP ligand for Am3+ by −52.0 kJ mol−1, and better selectivity of the BTPhen ligand for Cm3+ by −24.7 kJ mol−1.

The selective partitioning of trivalent actinides (An(III)) from high-level liquid waste (HLLW) is considered as an essential step in the management of spent nuclear fuel. The i-SANEX process for the separation of An(III) from the co-existing lanthanides (Ln(III)) in 4 M nitric acid solution and simulated HLLW was studied using a couple of symmetrical diglycolamides (TODGA and TDDGA) and an unsymmetrical diglycolamide (D3DODGA) in n-dodecane as the extraction phase. The selective stripping of Am(III) from the loaded organic phase containing trivalent Ln(III) was investigated using aqueous soluble bis-1,2,4-triazine derivatives such as SO3-Ph-BTP, SO3-Ph-BTBP and SO3-Ph-BTPhen in dilute nitric acid solution. The results revealed that the SF of Eu(III) over Am(III) decreased with increase in the concentration of nitric acid in all cases and SF decreased in the order SO3-Ph-BTP > SO3-Ph-BTBP > SO3-Ph-BTPhen. The co-stripping of lighter lanthanides (La, Ce, Pr, Nd) was also observed during the recovery of Am(III).

Selectivity between Am3+ and Cm3+ was investigated after their aqueous complexation with three structurally tailored hydrophilic bis-(1,2,4-triazin-3-yl) ligands followed by their extraction with N,N,N'N'-tetraoctyl diglycolamide (TODGA) dissolved in an ionic liquid (C4mim·Tf2N). The three hydrophilic ligands used were SO3PhBTP, SO3PhBTBP, and SO3PhBTPhen. It was evident from the solvent extraction studies that SO3PhBTP formed a stronger complex with Cm3+ than with Am3+, but SO3PhBTPhen showed better complexation ability for Am3+ than for Cm3+, and SO3PhBTBP showed no selectivity for the two actinide ions. DFT calculations indicated that the coordinating 'N' atoms in BTP were more co-planar in the complex and this co-planarity was higher in the Cm3+ complex as compared to that in Am3+. In the case of BTBP and BTPhen ligands, on the other hand, the co-planarity was more pronounced in the Am3+ complexes. Mayer's bond order calculations of M-N bonds in the complexes also indicated a reversal of the complexation ability of the BTP and BTPhen ligands for Am3+ and Cm3+. Calculations of the complexation energies further supported the higher selectivity of the BTP ligand for Am3+ by -52.0 kJ mol-1, and better selectivity of the BTPhen ligand for Cm3+ by -24.7 kJ mol-1.

Preferential stripping of the trivalent actinide ions such as Am(III) from the organic extract containing a mixture of Am(III) and Eu(III) by a suitable separation method is one of the most challenging areas of research which can find application in the radioactive waste management scheme. In the present study, a comparative evaluation of aqueous soluble tetrasulphonated derivatives of bis-triazinyl pyridine (BTP, LI), bis-triazinyl bipyridine (BTBP, LII) and bis-triazinyl phenanthroline (BTPhen, LIII) was done for the preferential stripping of Am(III) from a mixture of Am(III)/Eu(III) in the N,N,N′,N′-tetra-n-octyl diglycolamide (TODGA) extract. The results obtained in the solvent extraction studies were used for setting up of flat sheet supported liquid membrane based separation systems where the feed phase contained 1 M HNO3 spiked with the 241Am and 152,154Eu radiotracers while the receiver phase contained 0.01 M solutions of the aqueous soluble complexing agents in the presence of 1 M HNO3. Analogous studies were carried out using polypropylene hollow fibers leading to micro extraction of both Am(III) and Eu(III) and preferential stripping of Am(III) where promising separation behavior was observed, especially in the cases of LI and LIII with the DF values of 66 and 72, respectively for Am3+ over Eu3+ along with >80% recovery of Am.

The process methods developed for partitioning of trivalent actinides from high-level liquid waste (HLLW) are being focussed on single-cycle processing approaches. This method involves the separation of trivalent actinides and chemically similar lanthanides, as a group, from HLLW followed by the mutual separation of lanthanides and actinides from the loaded organic phase using aqueous soluble complexing agents. The potential solvents identified for the group separation of trivalents from HLLW are 1) 0.2 M TODGA (N,N,N’N′-tetraoctyldiglycolamide) + 5% octanol / n-DD, 2) 0.2 M TODGA + 0.5 M TBP (tri-n-butylphosphate) / n-DD, 3) 0.1 M TODGA + 0.25 M HDEHP (di-(2-ethylhexyl)phosphoric acid) / n-DD, 4) 0.2 M TDDGA (N,N,N’N′-tetradecyldiglycolamide) / n-DD, 5) 0.2 M D3DODGA (N,N-didodecyl-N’N′-dioctyldiglycolamide) / n-DD, 6) 0.4 M DOHyA (N,N-dioctyl-2-hydroxyacetamide) / n-DD. The extraction behaviour of Am(III) and Eu(III) from dilute nitric acid solution (0.1 M to 1 M) containing aqueous soluble nitrogen-donor derivative, SO3-Ph-BTP, was studied in the above solvents. The separation factor (SF) of Eu(III) over Am(III) was determined. Among the different solvents investigated, the SF achieved in TDDGA and D3DODGA was quite higher than other solvents, and recommended for the single-cycle separation of trivalent actinides from HLLW.

More than three trillion tonnes of macro-plastics and microplastics dumped into our environment causes irreversible damage to our ecosystem. Removing these non-biodegradable materials is beyond the skill of the human capacity even with the best available technologies. One of the best scientific approaches to resolve this issue is to develop degradable and eco-friendly materials known as green composites. A green composite should consist of eco-friendly properties such as quick degradation, non-toxic product release to the environment, eco-recycling, and easy solubility in water. Materials of both synthetic and natural origin could play a significant role in achieving the objective of preserving our environment and sustained growth. To accelerate the degradation of non-biodegradable polymers, additives are added to speed up the process. Oxo-degradable polymers come under this category. Polymers with hydrolyzable backbone degrade fast in aqueous environments. Aliphatic polyesters, polyglycolide, polylactide, polycaprolactum, poly(butylene succinate), and polyurethane, are some of the easily hydrolyzable materials of synthetic origin. Proteins from animal and vegetable origin, polysaccharides, are green materials of natural origin. Recently, hybrid materials consisting of both synthetic and natural origin green composites have been developed for advanced applications. Application of the green composites involves packaging industry, controlled release of nutrients and pesticides in agriculture, biomedical, automotive, and electronics applications. Immense opportunities are available to develop green materials and the best research efforts have been taken by humanity to make our environment safe. In this chapter, a review of versatile applications of degradable polymers is presented.

We show that iridium complexes incorporating a tetrazolate ligand can be used as new highly phosphorescent emitters in the fabrication of high-efficiency organic light emitting devices (OLEDs). The nature of the excited states of these Ir(iii) complexes was probed by means of electrochemical analysis, absorption and photoluminescence spectroscopies and with the aid of TD-DFT calculations. To demonstrate the high stability of these classes of complexes we used TGA and DSC characterizations. These complexes are used as dopant emitters in the emissive layers. The as-fabricated OLEDs display high-efficiency and high-brightness with blue, green and yellow/orange emission.

The diastereoselective direct one-pot three-components Mannich reaction of cyclododecanone (CDD), which has a unique conformation with aromatic aldehydes and anilines in the presence of catalytic amount of ammonium acetate was studied. The catalyzed reaction offered high yield, high diastereoselectivity, and simple workup. The addition of aniline to the aldol product took place, and this addition was made to the less hindered α-side. The Mannich derivatives were found to exhibit anti-cancer activities against six human cancer cell lines. This was observed using the CCK-8 nonradioactive colorimetric assay and the results were compared with MCFA10 normal breast epithelium cell line. A significant difference was observed in anti-cancer activity of anti (7f–7h) and syn (7ff–7hh) isomers in human cancer cell lines. The diastereoselective direct one-pot three-components, Mannich reaction of CDD, having unique conformation, with aromatic aldehydes and anilines in the presence of catalytic amount of NH4OAc giving anti/syn products was studied. The β-amino-carbonyl compounds are potent human anti-cancer cell lines and analogues of 7h–g anti-isomers are active in anti-cancer cell line whereas 7hh–gg syn-isomer is inactive.

We report the synthesis of single chain white light-emitting polyfluorene (PF)-based copolymers containing a novel red iridium complex ((CVz-PhQ)2IrdbmBr), benzothiadiazole (BT), and 2,5-bisphenyl-1,3,4-oxadiazole (OXD) segments. The resulting copolymers were highly soluble in common organic solvents and could be easily spin-coated onto an indium-tin oxide (ITO)-coated glass substrate to obtain high quality optical thin films. The weight-average molecular weight (Mw) and polydispersity of the copolymers were (17.5–36.3) × 104 and 1.54–1.65, respectively. We fabricated white polymer light-emitting diodes (WPLEDs) in ITO/PEDOT:PSS/PVK/copolymer/CsF/Ca/Al, both with and without the poly(9-vinylcarbazole) (PVK) interlayer. By carefully controlling the concentrations of the low-energy-emitting species in the resulting copolymers, white light-emission with contributions from each of the three primary colors was achieved. By incorporating 2 mol% of an electron transporting material, OXD, as a comonomer into the copolymer backbone and inserting a PVK interlayer, the external quantum efficiency (EQE) and luminance efficiency (LE) of the WPLEDs were enhanced. The turn-on voltages of the copolymers were in the range of 5.5–7.5 V, and the maximum EQE and LE were 1.79% and 1.89 cd/A with CIE coordinates of (0.32, 0.34), which are close to the standard for white light emission.

Two kinds of low-band gap polymers, poly[{N-(1-octyldecyl)-2,7-carbazole)}-alt-{3,6-bis(phenylene-1,4-diyl)-2,5-di(1-octyldecyl)-2,5-dihydropyrrolo[3,4]pyrrole-1,4-dione}], poly(Cvz-PhDPP) and poly[{N-(1-octyldecyl)-2,7-carbazole)}-alt-{3,6-bis(pyridinyl-5-yl)-2,5-di(1-octyldecyl)-2,5-dihydropyrrolo[3,4]pyrrole-1,4-dione}], poly(Cvz-PyDPP), were synthesized by palladium-catalyzed Suzuki polymerization. Bulk heterojunction solar cells with an ITO/PEDOT/polymer:PC71BM/LiF/Al configuration were fabricated, which shows open-circuit voltage, short-circuit current density, fill factor, and power conversion efficiency of 0.76 V, 4.01 mA/cm2, 0.35, and 1.07% under AM 1.5 irradiation (100 mW/cm2), respectively.

Selective synthesis of 2,4-diaryl-2,3-dihydro-3H-naphthoACHTUNGRE[1,2- e]-1,3-oxazines and Schiff bases ((E)-[1-arylmethyl(benzylideneamino)]-naphth-2-ols) that contain two identi-cal or two different aryl substituentswas achieved through one-pot synthe-sis with ammonium acetate. From theproposed mechanism the dual role ofammonium acetate was identified.The synthesized products were charac-terized by 1 H and 13 C NMR spectros-copy, as well as FTIR and mass spec-trometry. Crystal structures of the 1,3-oxazines and Schiff base derivativeswere examined. A notable feature isthe conspicuous absence of strongdonors (NH/OH) in any intermolecu-lar hydrogen-bonding scheme. In-stead, packing is characterized byweak intermolecular C H···O, CH···p and C Cl···p interactions, whichlead to dimeric and zig-zag one-di-mensional molecular patterns. The ox-azine moiety of the tricyclic ringsystem predominantly adopts a half-chair conformation. The present Man-nich procedure is an environmentallybenign and cost-effective method forthe preparation of industrially andpharmaceutically useful heterocyclicscaffolds.Keywords: ammonium acetate ·crystal structure · oxazines · Schiffbases

In an effort to provide a green synthetic route for heterocyclic scaffolds, new macro analogs of acyclic Mannich derivatives have been synthesized in good yields in a one-pot, efficient fashion. The acyclic symmetrical and unsymmetrical 2-[(E)-(benzylideneamino)(aryl)methyl]cyclododecanones have been synthesized by condensation of cyclododecanone, aromatic aldehyde, and ammonium acetate in ethanolic media. By infrared, NMR, and mass spectral analyses, their structures were determined. Examination of crystal structure of a p-Cl and o-Br analogs reveals the minimum energy [3333] square conformation of cyclododecanone ring. In the crystal, molecules aggregate in dimeric subunits formed by C-Cl … π and C-H..π interactions. The reported one-pot, multichain reaction of macrocycles is the first synthetic attempt of acyclic compounds in this type of Mannich reaction involving ketones containing active methylene groups. Supplemental materials are available for this article. Go to the publisher's online ed...

Derivatives of azabicyclo[3.3.1]nonanone tend to prefer for weak interactions in the crystal over strong N–H···O hydrogen bonds. The main stabilizing forces in the investigated azatricyclo[7.3.1.02,7]trideca-trienone derivatives are C–H···O, N–H···π and C–H···π interactions, leading to interesting structural patterns. The azabicyclo[3.3.1]nonanone ring adopts chair-envelope conformation having exo-C2,C4-aromatic substituents. Amino NH is in trigonal pyramidal configuration. The interesting stereochemistry of azabicyclo[3.3.1]nonanone, driving exceptional preference for weaker interactions over strong hydrogen bonds serves a useful example toward engineering and design strategy, and structure prediction methodologies.

In this study, an attempt has been made to use waste vegetable oil as a fuel for a cooking stove. Suitable modifications have been made in the kerosene stove for use with vegetable oil as fuel. The efficiency of the stove using vegetable oil as fuel is observed to be as high as 48.9% as compared to 34.9% with that of a conventional stove when a flat copper bottom vessel is used. Corresponding efficiency increase is also observed with other vessels.

In an effort to provide a green synthetic route for heterocyclic scaffolds, new macro analogs of acyclic Mannich derivatives have been synthesized in good yields in a one-pot, efficient fashion. The acyclic symmetrical and unsymmetrical 2-[(E)-(benzylideneamino)(aryl)methyl]cyclododecanones have been synthesized by condensation of cyclododecanone, aromatic aldehyde, and ammonium acetate in ethanolic media. By infrared, NMR, and mass spectral analyses, their structures were determined. Examination of crystal structure of a p-Cl and o-Br analogs reveals the minimum energy [3333] square conformation of cyclododecanone ring. In the crystal, molecules aggregate in dimeric subunits formed by C-Cl … π and C-H..π interactions. The reported one-pot, multichain reaction of macrocycles is the first synthetic attempt of acyclic compounds in this type of Mannich reaction involving ketones containing active methylene groups. Supplemental materials are available for this article. Go to the publisher's online ed...

A novel, simple, mild, and faster synthesis of the title compounds is developed from readily available starting materials including a convenient work-up.

A simple and efficient three components domino reaction of γ-butyrolactam (2-pyrrolidinone), aromatic aldehyde and substituted thiophenol catalyzed by elemental iodine resulted in the formation of 1-((phenylthio)(phenyl)methyl)pyrrolidin-2-one derivatives. The stability of the synthesized analogues was evaluated in stimulated gastric fluid (SGF) and bovine serum albumin (BSA). In vitro anticancer activity was investigated in the low micromolar range and a few analogues were found to possess good activity. This current protocol provides several advantages like shorter reaction time, excellent yield and convenient work-up.

The inversion-related molecules of the title compound, C26H21F2NO, associate into closed dimeric subunits via co-operative C—H...π interactions. Two non-classical C—H...O and one C—H...N intramolecular hydrogen bonds are also found in the crystal structure. The piperidin-4-one ring adopts a sofa conforamtion with the 1-benzyl group in the equatorial position, and the equiplanar fluorophenyl substituents in the 3- and 5-positions stretched out on either side. The 1-benzyl group is disposed towards the substituent in the 6th position of the piperidin-4-one ring. The 3,5-diene units possess E configurations.

The fluorinated and non-fluorinated dibenzylidene-4-piperidones were synthesized and their structures examined using X-ray crystallography. Interestingly, the para-fluorosubstituted dibenzylidene compound, in contrast to other analogs, is characterized by C–H...F bonded one-dimensional packing motif. To evaluate the ability of hydrogen bond donors and acceptors for forming interactions, in general and competitive situation, we have defined statistical descriptors. Analysis of Cambridge Structural Database using these newly defined parameters reveals high propensity of C–H...F interactions in organic crystals. The present structural study suggests much larger role of fluorine driven intermolecular interactions that are even though weak, but possess significant ability to direct and alter the packing.