Limits of locally–globally convergent graph sequences

The colored neighborhood metric for sparse graphs was introduced by Bollobás and Riordan [BR11]. The corresponding convergence notion refines a convergence notion introduced by Benjamini and Schramm [BS01]. We prove that even in this refined sense, the limit of a convergent graph sequence (with uniformly bounded degree) can be represented by a graphing. We study various topics related to this convergence notion such as: Bernoulli graphings, factor of i.i.d. processes and hyperfiniteness.     

Design,Synthesis, and Antibacterial Evaluation of Some Novel 3′-(Phenylamino)-1′H-spiro[indoline-3,2′-quinazoline]-2,4′(3′H)-dione Derivatives

A combinatorial synthesis and evaluation of antibacterial activity against clinically isolated resistant strains of Gram-positive and Gram-negative bacteria of 3′-(phenylamino)-1′H-spiro[indoline-3,2′-quinazoline]-2,4′(3′H)-dione derivatives is described.     

Metal- and Catalyst-Free Synthesis of 2-Substituted-Phthalimides Using 2-(Arenesulfonyl)Phthalimide as Key Reagents

Phthalimide derivatives are important in medicinal chemistry, several phthalimidation methodologies have been developed. Here, we report a facile, metal-free, and catalyst-free method for the preparation of N-phthalimides in good to excellent yield by reacting 2-(arenesulfonyl)phthalimides with various amine substrates.     

A Targeted Review of Current Progress,Challenges and Future Perspective of g-C3N4 based Hybrid Photocatalyst Toward Multidimensional Applications

The increasing demand for searching highly efficient and robust technologies in the context of sustainable energy production totally rely onto the cost-effective energy efficient production technologies. Solar power technology in this regard will perceived to be extensively employed in a variety of ways in the future ahead, in terms of the combustion of petroleum-based pollutants, CO₂ reduction, heterogeneous photocatalysis, as well as the formation of unlimited and sustainable hydrogen gas production. Semiconductor-based photocatalysis is regarded as potentially sustainable solution in this context. g-C₃N₄ is classified as non-metallic semiconductor to overcome this energy demand and enviromental challenges, because of its superior electronic configuration, which has a median band energy of around 2.7 eV, strong photocatalytic stability, and higher light performance. The photocatalytic performance of g-C₃N₄ is perceived to be inadequate, owing to its small surface area along with high rate of charge recombination. However, various synthetic strategies were applied in order to incorporate g-C₃N₄ with different guest materials to increase photocatalytic performance. After these fabrication approaches, the photocatalytic activity was enhanced owing to generation of photoinduced electrons and holes, by improving light absorption ability, and boosting surface area, which provides more space for photocatalytic reaction. In this review, various metals, non-metals, metals oxide, sulfides, and ferrites have been integrated with g-C₃N₄ to form mono, bimetallic, heterojunction, Z-scheme, and S-scheme-based materials for boosting performance. Also, different varieties of g-C₃N₄ were utilized for different aspects of photocatalytic application i. e., water reduction, water oxidation, CO₂ reduction, and photodegradation of dye pollutants, etc. As a consequence, we have assembled a summary of the latest g-C₃N₄ based materials, their uses in solar energy adaption, and proper management of the environment. This research will further well explain the detail of the mechanism of all these photocatalytic processes for the next steps, as well as the age number of new insights in order to overcome the current challenges.     

Polycarbonate-coated magnetic nanoparticles for the extraction of imipramine and its primary metabolite from urine

This study introduces a reliable and inexpensive magnetic dispersive solid phase extraction to extract imipramine and its primary metabolite (desipramine) from urine samples. To accomplish this aim, Fe₃O₄ magnetic nanoparticles were synthesized by sonication, subsequently, polycarbonate was precipitated gradually onto the surface of them to form the adsorbent. Extraction recoveries of 85% and 76%, enrichment factors of 57 and 51, limits of detection of 2.5 and 2.8 μg/L, and limits of quantification of 8.3 and 9.3 μg/L were obtained for imipramine and desipramine under the optimal conditions, respectively. In addition, relative standard deviations for intra- (n = 6) and inter-day (n = 5) precisions at two concentrations (50 and 100 μg/L of each analyte) were less than or equal to 4%. Short extraction time, good repeatability, high enrichment factors, and simplicity are the main advantages of the proposed method.     

Assessing silicon deposits in Zilfi province,Saudi Arabia,using XRF and XRD techniques

The aim of this project is to create a geochemical database of the Nafud Desert in Zilfi Province, which lies 260 km northwest of Riyadh, capital of Saudi Arabia, and assess its potential as a silicon mine. The area of study was surveyed during December 2012 collecting 21 geological samples from 7 places (Alsabla, Almatal, Shlwan, Alaaga, Jaway, Magra and Althuare). Elemental composition was determined using X‐ray fluorescence spectrometry, while mineral content and crystallography analysis was performed using X‐ray diffraction. Analysis results revealed that silicon was abundant in the area, in fairly homogeneous amounts. Silica was found in concentrations of around 93% per sampled mass, and silicon concentrations were around 42%, in the surface layers down to the depth of 40 cm. Other elements (Al, K, Ca, Ti, Cr, Mn, Fe, Sr, Zr and Pd ) were present in very low concentrations, except for aluminium oxide, which was present in three areas (Jaway, Magra and Althuare) at concentrations around 5%, while Alsabla samples showed higher concentrations of CaO. Thus, according to the results, the Nafud Desert is a rich source of silicon that can be exploited very cheaply because of the presence of the raw material on the surface. Copyright © 2016 John Wiley & Sons, Ltd.     

A multi‐MHz single‐shot data acquisition scheme with high dynamic range: pump–probe X‐ray experiments at synchrotrons

The technical implementation of a multi‐MHz data acquisition scheme for laser–X‐ray pump–probe experiments with pulse limited temporal resolution (100 ps) is presented. Such techniques are very attractive to benefit from the high‐repetition rates of X‐ray pulses delivered from advanced synchrotron radiation sources. Exploiting a synchronized 3.9 MHz laser excitation source, experiments in 60‐bunch mode (7.8 MHz) at beamline P01 of the PETRA III storage ring are performed. Hereby molecular systems in liquid solutions are excited by the pulsed laser source and the total X‐ray fluorescence yield (TFY) from the sample is recorded using silicon avalanche photodiode detectors (APDs). The subsequent digitizer card samples the APD signal traces in 0.5 ns steps with 12‐bit resolution. These traces are then processed to deliver an integrated value for each recorded single X‐ray pulse intensity and sorted into bins according to whether the laser excited the sample or not. For each subgroup the recorded single‐shot values are averaged over ～10⁷ pulses to deliver a mean TFY value with its standard error for each data point, e.g. at a given X‐ray probe energy. The sensitivity reaches down to the shot‐noise limit, and signal‐to‐noise ratios approaching 1000 are achievable in only a few seconds collection time per data point. The dynamic range covers 100 photons pulse^?1 and is only technically limited by the utilized APD.     

On the biological properties of alkynyl phosphine gold(i) complexes

Golden times for metal-based drugs? Alkynyl triphenylphosphine gold(I) complexes display interesting biological properties and show high potential for future drug development. They are strong inhibitors of the enzyme thioredoxin reductase, trigger antiproliferative effects in tumor cells, and influence tumor cell metabolism, mitochondrial respiration, and angiogenesis in zebrafish embryos.     

Application of the dissociative electron transfer theory and its extension to the case of in-cage interactions in the electrochemical reduction of arene sulfonyl chlorides

Important aspects of the electrochemical reduction of a series of substituted arene sulfonyl chlorides are investigated. An interesting autocatalytic mechanism is encountered where the starting material is reduced both at the electrode and through homogeneous electron transfer from the resulting sulfinate anion. This is due to the homogenous electron transfer from the two-electron reduction produced anion (arene sulfinate) to the parent arene sulfonyl chloride. As a result, the reduction process and hence the generated final products depend on both the concentration of the substrate and the scan rate. A change is also observed in the reductive cleavage mechanism as a function of the substituent on the phenyl ring of the arene sulfonyl chloride. With 4-cyano and 4-nitrophenyl sulfonyl chlorides a "sticky" dissociative ET mechanism takes place where a concerted ET mechanism leads to the formation of a radical/anion cluster before decomposition. With other substituents (MeO, Me, H, Cl, and F) a "classical" dissociative ET is followed, where the ET and bond cleavage are simultaneous. The dissociative electron transfer theory, as well as its extension to the case of strong in-cage interactions between the produced fragments, along with gas phase chemical quantum calculations results helped us to rationalize both the observed change in the ET mechanism and the occurrence of the "sticky" dissociative ET mechanism. The radical/anion pair interactions have been determined both in solution as well as in the gas phase. The study also shows that despite the low magnitude of in-cage interactions in acetonitrile compared to the gas phase their existence strongly affects the dynamics of the involved reactions. It also shows that, as expected, these interactions are reinforced by the existence of strong electron-withdrawing substituents. The occurrence of an autocatalytic process and the existence of the radical/anion interaction may explain the differences previously observed in the reduction of these compounds in different media.     

Cytotoxicity and cellular impact of dinuclear organoiridium DNA intercalators and nucleases with long rigid bridging ligands

The DNA binding modes and cleavage properties of novel dinuclear Ir(III) polypyridyl (pp) complexes [{(η(5)-C(5)Me(5))Ir(pp)}(2)(μ-B)](CF(3)SO(3))(4) depend on the lengths of their rigid bridging dipyridinyl ligands B. Mono-intercalation and strong DNA cleavage properties were observed for the dipyrido[2,3-a:2',3'-c]phenazine (dppz) complexes 1 (B = 4-[(E)-2-(4-pyridinyl)ethenyl]pyridine) and 3 (B = 4-(2-pyridin-4-ylethynyl)pyridine), whose intracationic Ir···Ir' distances are about 13.1 and 13.3 ?, respectively. In contrast, UV/Vis and CD spectra were in accordance with a stable intertwined bis-intercalation mode for pairs of cations of 5 (B = 1,4-di(2-pyridin-4-ylethynyl)benzene), whose much longer Ir···Ir' distance of 20.6 ? allows a stack of five aromatic chromophores to be sandwiched between its effectively parallel dppz ligands. Whereas both 1 and 3 cleaved DNA in the dark, complex 5 exhibited only photoinduced nuclease activity. A significantly higher antiproliferative activity towards MCF-7 breast carcinoma cells was observed for the nucleases 1 and 3, whose IC(50) values of 0.61 and 0.49 were much lower than that of 2.2 μM for bis-intercalator 5. Values of 3.8 μM, only slightly higher than that of 5, were recorded for the 5,6-dimethylphenanthroline complexes 4 and 6, whose bridging ligands are identical to those of 3 and 5, respectively. Marked antileukemic activity (IC(50) = 6-7 μM) associated with increased levels of reactive oxygen species and apoptosis induction was recorded for both 3 and 5 towards Jurkat cells at concentrations of 5 μM and above. Online studies with a sensor chip system indicated that 5 μM solutions of these complexes invoke a rapid and massive reduction in MCF-7 cell respiration.