Structure of 3,6-di(p-methoxyphenyl)-2,7-dihydro-1,4,5-thiadiazepine

The title compound C₁₈H₁₈N₂O₂S is monoclinic with unit-cell dimensionsa=8.849(10),b=9.185(11),c=20.257(9) Å,=109.28(10)°. The space group isP2₁/c, withZ=4. Data were measured by photographic methods. The structure was solved by direct methods. A full-matrix least-squares refinement converged toR=0.10. All atoms except sulfur were assigned individual isotropic thermal parameters. The conformation of the thiadiazepine ring system is distorted boat shaped, as indicated by torsion angle studies.     

Simple Organic Salts Having a Naphthalenediimide (NDI) Core Display Multifunctional Properties: Gelation,Anticancer and Semiconducting Properties

Following a supramolecular synthon rationale, a dicarboxylic acid derivative having a naphthalenediimide (NDI) core, namely, bis‐N‐carboxymethyl naphthalenediimide ( NDI‐G ), was reacted with n‐alkyl amines with varying alkyl chain lengths to generate a new series of primary ammonium dicarboxylate (PAD) salts. The majority of the salts (≈85 %) were found to gel various polar solvents. The gels were characterized by dynamic rheology and high‐resolution electron microscopy. Single‐crystal and powder X‐ray diffraction analyses were used to study the supramolecular synthon present in one of the gelator salts (i.e., S8 ). Charge‐transfer (CT)‐induced gelation with donor molecules such as anthracene methanol ( Ant ) and pyrene ( Py ) was also possible with S8 . The CT complex ( S8.Ant ) displayed anticancer activity as probed by cell migration assay on the highly aggresive breast cancer cell line MDA‐MB‐231 . The DMSO gel of S8.Ant also displayed semiconducting behavior. To the best of our knowledge, simple organic salts with an NDI core that display such mulitifunctional properties are hitherto unknown.     

Rheoreversible Metallogels Derived from Coordination Polymers

A series of mixed‐ligand‐based Cd^II/Co^II coordination polymers (CPs) that were derived from two bis(pyridyl)–bis(amide) ligands, 4,4′‐oxybis(N‐(pyridin‐3‐yl)benzamide) ( LP ) and 4,4′‐oxybis(N‐(pyridin‐4‐yl)benzamide) ( LP1 ), and a variety of dicarboxylates isophthalates, terephthalates, 1,2‐carboxytranscinamates, and 1,3‐ and 1,4‐phenylene dicarboxylates were synthesized based on a rationale that they would occlude solvate guests inside their crystal lattice, thereby rendering these CPs suitable as metallogelators. The CPs were characterized by using single‐crystal X‐ray diffraction, elemental analysis, powder X‐ray diffraction (PXRD), FTIR spectroscopy, and thermogravimetric analysis (TGA). Structural analyses revealed that the majority of the CPs were lattice‐occluded molecular solids, which provided us with an opportunity to study their gelation behavior. We observed that, out of eight CPs that were tested, seven were able to produce metallogels. A thorough study of the rheological behavior of the metallogels was performed and CPG1 , CPG2 , CPG4 , and CPG5 were found to exhibit rheoreversible behavior, which was further confirmed by rheological experiments. Interestingly, ligand LP was found to form an aqueous gel, which was exploited to produce silver nanoparticles.     

Determination of isonicotinic acid hydrazide (isoniazid) by the weisz ring-oven technique

A simple precise method is described for the determination of isonicotinic acid hydrazide (isoniazid) alone, and in mixtures with aspirin, paracetamol and streptomycin, by reaction with vanillin in the Weisz ring-oven technique; 0.1–15 μg of isoniazid can be determined with errors of 2–2.7%.     

Evaluation of 1st and 2nd generation of poly(amidoamine) dendrimer functionalized carbon nanotubes for the efficient removal of neptunium

Journal of Radioanalytical and Nuclear Chemistry - Herein, sorption of pentavalent neptunium from aqueous acidic solution was carried out onto 1st and 2nd generation of poly(amidoamine) dendrimer...     

Synthesis, characterisation, and DC conductivity of polyaniline-lead oxide composites

The polyaniline-PbO composites of various mass fractions were prepared by in situ polymerisation. The prepared samples were characterised by FTIR, and the dominant peaks confirmed the formation of polyaniline-PbO composites. The SEM study shows a granular agglomerated morphology, and increases with an increase in the lead oxide mass % in polyaniline. Direct current (DC) conductivity (σ _DC) was studied as a function of temperature (T). From these studies, it was found that conductivity increased at higher temperatures due to the polarons hopping from one localised state to another. DSC studies reveal, the decrease in peak temperature from 273°C (pure PANI) to 169.2°C, 193.5°C, 218.4°C, 235.2°C, and 224.2°C, respectively for the various mass fractions (10 %, 30 %, 20 %, 40 %, and 50 %) of polyaniline-PbO composites.     

Biodegradation of chemically modified wheat gluten-based natural polymer materials

Biodegradation of a series of chemically modified thermally processed wheat gluten (WG)-based natural polymers were examined according to Australian Standard (AS ISO 14855). Most of these materials reached 93-100% biodegradation within 22 days of composting, and the growth of fungi and significant phase deformation were observed during the process. Chemical crosslinking did slow down the rate or reduce the degree of the biodegradation with different behaviours for different modified systems. The segments containing structures derived from the reactions with additives such as tannin or epoxidised soybean oil remained in the degradation residues while the glycidoxypropyl trimethoxysilane agent produced ∼20% un-degraded residues containing silicon-crosslinking structures. The biodegradation rate of each component of the materials was also different with the protein and starch components degraded fast but lipid degraded relatively slowly.     

Analysis of multitone microwave signals on optical fiber system using external laser modulation

In this paper, we Analyze multitone microwave signals on optical fiber with different tone signals and utilizing various possibilities of regeneration and amplification by different means. We compare out the performance analysis of Erbium doped fiber amplifiers (EDFAs) and Semi-conductor Optical Amplifiers (SOA). One tone's frequency varies from 1 to 20 GHz through parametric runs and other has fixed frequency of 5 GHz and third harmonic tones may be monitored.     

Microdetermination of Xanthates

Summary A rapid, convenient and accurate method for the determination of xanthates has been developed. N-bromosuccinimide has been used to displace iodine from potassium iodide which in turn oxidizes xanthate to dixanthogen. The p_H 4 is optimum for the determination. The maximum relative standard deviation is 6% in the case of ethyl potassium xanthate when a 0.5 mg sample was taken.

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Zusammenfassung Ein genaues Verfahren zur raschen Bestimmung von Xanthat wurde entwickelt. N-Bromsuccinimid dient zur Freisetzung von Jod aus KJ; Jod oxydiert Xanthat zu Dixanthogen. Das optimale p_H für die Bestimmung ist 4. Die größte relative Standardabweichung ist 6% bei einer Einwaage von 0,5 mg Kaliumäthylxanthat.