bluuebunny/crossref_metadata_2025 huggingface dataset:
Carrier Transport in CH3NH3PbI3 Films with Different Thickness for Perovskite Solar Cells
Authors: Zhang Bo , Zhang Ming‐Jia , Pang Shu‐Ping , Huang Chang‐Shui , Zhou Zhong‐Min , Wang Dong , Wang Ning , Cui Guang‐Lei
Published: July 2016

The typical broad absorption features have enabled halide perovskite to be a promising candidate of the next generational solar cell materials. However, the fundamental properties, upon which the photoelectric performance of perovskite device is based, are currently still not clear. Herein, the photovoltaic efficiencies in perovskite films with various thicknesses have been investigated to reveal a direct correlation between internal structure factors, such as crystal orientation, grain size, and photoelectric performance of perovskite films. It is found that the photovoltaic efficiency of perovskite films, especially with the optimal thickness around 300 nm, is significantly increased, which can be ascribed to the improved carrier transport properties resulting from the preferred crystal structure. When the film thickness diverges from 300 nm, the extra charge recombination with decreasing mobility leads to the reduction of photovoltaic efficiency again in perovskite solar cells. These results demonstrate crystal structure as one of the decisive roles in device properties, which are helpful to improve photovoltaic performance of perovskite solar cells.
Ultra‐Facile Fabrication of Stretchable and Transparent Capacitive Sensor Employing Photo‐Assisted Patterning of Silver Nanowire Networks
Authors: Jun Sungwoo , Ju Byeong‐Kwon , Kim Jong‐Woong
Published: July 2016

Transparent electrodes that can be patterned in a simple manner and remain electrically conductive even under considerable strain are desirable for applications in stretchable and wearable devices. This paper introduces an ultra‐facile, fast, and chemical‐free method to produce silver nanowire (AgNW) patterns on a stretchable polymer. The AgNWs are deposited on thermoplastic urethane (TPU) and irradiated by intense pulsed light. This results in the fusion of the polymer through the surface of the AgNWs, thereby producing an embedded structure of AgNWs/TPU. A photomask is used to limit the areas affected by the radiation. After liquid washing, the AgNWs in areas that are not irradiated are mechanically separated by peeling. This simple procedure enables stretchable and transparent conducting patterns to be fabricated. The fusion procedure ensures that the patterned AgNWs are robustly adhered to the TPU even when stretched by large strains higher than 33%. Stretch‐and‐release testing reveals that the resistance of the electrodes reversibly varied, implying that it has good stretchability. The simple fabrication of a reliable stretchable capacitive sensor is demonstrated by employing this facile approach, in that the sensitivity does not deteriorate after severe stretching.
Facile Synthesis of 3‐Halobenzo‐heterocyclic‐2‐carbonyl Compounds via in situ Halogenation‐Oxidation
Authors: Jiang Xiaojian , Yang Junjie , Zhang Feng , Yu Pei , Yi Peng , Sun Yewei , Wang Yuqiang
Published: July 2016

A facile method to synthesize 3‐halobenzo‐heterocyclic‐2‐carbonyl compounds is described. Mechanistic studies suggested that a halo‐cyclization process, which generated the unstable spiro‐acetal transition state and readily convertible to the corresponding carbonyl compound might be involved. Diverse 3‐halobenzo‐heterocyclic‐2‐carbonyl compounds could be synthesized with up to 95 % yield in mild conditions with inexpensive starting materials.

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A “Grafting to” Approach to Synthesize Low Cytotoxic Poly(aminoamide)‐Dendrimer‐grafted Fe3O4 Magnetic Nanoparticles
Authors: Banaei Masoud , Salami‐Kalajahi Mehdi
Published: July 2016

Poly(aminoamide) (PAMAM) dendrimer with 3.5 generation was synthesized with ethylenediamine as the primary core and methyl acrylate. Also, Fe3O4 nanoparticles as magnetic ones were modified by (3‐aminopropyl)triethoxysilane (APTES) to fabricate amine‐functionalized magnetic nanoparticles (Fe3O4@APTES). Then, 3.5GD dendrimer was conjugated with Fe3O4@APTES to obtain dendrimer‐grafted magnetic nanoparticles (Fe3O4@3.5GD). The core‐shell structure of Fe3O4@3.5GD nanoparticles was revealed via TEM. Also, progression of each step was studied by FT‐IR, 1H NMR, CHN elemental analysis, and thermal gravimetric analysis (TGA). Vibrating sample magnetometer (VSM) was used to show that the synthesized nanoparticles keep their superparamagetic properties after synthesis process. Finally, in vitro cellular cytotoxicity was applied to evaluate the biocompatibility of synthesized structures and investigate the cytotoxic effect of grafted dendrimer using HeLa cells. As a resultS, about 20 wt. % of dendrimer grafting was obtained and good correlation was observed with VSM results. Also, 3.5GD dendrimer showed low cytotoxicity to HeLa cells while after dendrimer grafting, toxicity of Fe3O4@3.5GD slightly increased.
NiFe‐Based (Oxy)hydroxide Catalysts for Oxygen Evolution Reaction in Non‐Acidic Electrolytes
Authors: Dionigi Fabio , Strasser Peter
Published: July 2016

NiFe‐based (oxy)hydroxides are highly active catalysts for the oxygen evolution reaction in alkaline electrolyte solutions. These catalysts can be synthesized in different ways leading to nanomaterials and thin films with distinct morphologies, stoichiometries and long‐range order. Notably, their structure evolves under oxygen evolution operating conditions with respect to the as‐synthesized state. Therefore, many researchers have dedicated their efforts on the identification of the catalytic active sites employing in operando experimental methods and theoretical calculations. These investigations are pivotal to rationally design materials with outstanding performances that will constitute the anodes of practical commercial alkaline electrolyzers. The family of NiFe‐based oxyhydroxide catalysts reported in recent years is addressed and the actual state of the research with special focus on the understanding of the oxygen‐evolution‐reaction active sites and phase is described. Finally, an overview on the proposed oxygen‐evolution‐reaction mechanisms occurring on NiFe‐based oxyhydroxide electrocatalysts is provided.
Free‐Standing 3D Nanoporous Duct‐Like and Hierarchical Nanoporous Graphene Films for Micron‐Level Flexible Solid‐State Asymmetric Supercapacitors
Authors: Qin Kaiqiang , Liu Enzuo , Li Jiajun , Kang Jianli , Shi Chunsheng , He Chunnian , He Fang , Zhao Naiqin
Published: July 2016

High energy density and power density within a limited volume of flexible solid‐state supercapacitors are highly desirable for practical applications. Here, free‐standing high‐quality 3D nanoporous duct‐like graphene (3D‐DG) films are fabricated with high flexibility and robustness as the backbones to deposit flower‐like MnO2 nanosheets (3D‐DG@MnO2). The 3D‐DG is the ideal support for the deposition of large amount of active materials because of its large surface area, appropriate pore structure, and negligible volume compared with other kinds of carbon backbones. Moreover, the 3D‐DG preserve the distinctive 2D coherent electronic properties of graphene, in which charge carriers move rapidly with a small resistance through the high‐quality and continuous chemical vapor deposition‐grown graphene building blocks, which results in a high rate performance. Marvelously, ultrathin (≈50 μm) flexible solid‐state asymmetric supercapacitors (ASCs) using 3D‐DG@MnO2 as the positive electrode and 3D hierarchical nanoporous graphene films as the negative electrode display ultrahigh volumetric energy density (28.2 mW h cm−3) and power density (55.7 W cm−3) at 2.0 V. Furthermore, as‐prepared ASCs show high cycle stability clearly demonstrating their broad applications as power supplies in wearable electronic devices.
Optimization‐based support for process design under uncertainty: A case study
Authors: Steimel Jochen , Engell Sebastian
Published: July 2016

The use of two‐stage stochastic optimization for the support of the solution of process design problems in the early phase of process development where the different potential elements of the production process can only be described with significant uncertainty is discussed. The first stage variables are the design decisions which are fixed after the process has been built, while the second stage variables are the operational parameters which can be adapted to the realization of the uncertainties. The application of the approach to the design of a hydroformylation process in a thermomorphic solvent system is demonstrated. The proposed designs which are computed using the software framework FSOpt are analyzed and compared using different graphic representations which provide insight into what the most important design decisions are. Finally, the experience with the proposed formulation and solution techniques and point out where further advances are needed is reviewed. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3404–3419, 2016
A smart manufacturing methodology for real time chemical process diagnosis using causal link assessment
Authors: Rathinasabapathy Rajan , Elsass Michael J. , Josephson John R. , Davis James F.
Published: July 2016

Industrial chemical plant diagnosis is the task of analyzing process data to sufficiently pinpoint the causes of abnormal events as fast and as accurately as possible so corrective action can be taken in a timely manner. The need to identify failures explicitly and support human centered decision making becomes pronounced for enterprises. Qualitative diagnostic models offer robustness in capturing diagnostic behaviors when there is little or no data on fault conditions. This article develops, analyzes, and demonstrates a qualitative diagnostic methodology called Causal Link Assessment (CLA). CLA avoids the drawbacks of other methodologies while leveraging several new concepts that include dynamic pattern generation, single time step modeling with multitime step interpretation, and discretized, low granularity dynamic modeling. CLA is demonstrated for an existing ethylene production facility. Model building, robustness, reusability, unaccounted for faults and failures and alignment with emerging Smart Manufacturing infrastructure concepts are discussed. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3420–3431, 2016
Moving horizon closed‐loop production scheduling using dynamic process models
Authors: Pattison Richard C. , Touretzky Cara R. , Harjunkoski Iiro , Baldea Michael
Published: July 2016

The economic circumstances that define the operation of chemical processes (e.g., product demand, feedstock and energy prices) are increasingly variable. To maximize profit, changes in production rate and product grade must be scheduled with increased frequency. To do so, process dynamics must be considered in production scheduling calculations, and schedules should be recomputed when updated economic information becomes available. In this article, this need is addressed by introducing a novel moving horizon closed‐loop scheduling approach. Process dynamics are represented explicitly in the scheduling calculation via low‐order models of the closed‐loop dynamics of scheduling‐relevant variables, and a feedback connection is built based on these variables using an observer structure to update model states. The feedback rescheduling mechanism consists of, (a) periodic schedule updates that reflect updated price and demand forecasts, and, (b) event‐driven updates that account for process and market disturbances. The theoretical developments are demonstrated on the model of an industrial‐scale air separation unit. © 2016 American Institute of Chemical Engineers AIChE J, 63: 639–651, 2017
Genomic imbalance in the centromeric 11p15 imprinting center in three families: Further evidence of a role for IC2 as a cause of Russell–Silver syndrome
Authors: Cytrynbaum Cheryl , Chong Karen , Hannig Vickie , Choufani Sanaa , Shuman Cheryl , Steele Leslie , Morgan Thomas , Scherer Stephen W. , Stavropoulos Dimitri J. , Basran Raveen K. , Weksberg Rosanna
Published: July 2016

Russell–Silver syndrome is a heterogeneous disorder characterized by intrauterine growth retardation, postnatal growth deficiency, characteristic facial appearance, and other variable features. Genetic and epigenetic alterations are identified in about 60% of individuals with Russell–Silver syndrome. Most frequently, Russell–Silver syndrome is caused by altered gene expression on chromosome 11p15 due to loss of methylation at the telomeric imprinting center. To date there have been a handful of isolated clinical reports implicating the centromeric imprinting center 2 in the etiology of Russell–Silver syndrome. Here we report three new families with genomic imbalances, involving imprinting center 2 resulting in gain of methylation at this center and a Russell–Silver syndrome phenotype, including two families with a maternally inherited microduplication and the first pediatric patient with a paternally derived microdeletion. The findings in our families provide additional evidence of a role for imprinting center 2 in the etiology of Russell–Silver syndrome and suggest that imprinting center 2 imprinting abnormalities may be a more common cause of Russell–Silver syndrome than previously recognized. Furthermore, our findings together with previous clinical reports of genomic imbalances involving imprinting center 2 serve to underscore the complexity of the epigenetic regulation of the 11p15 region making it challenging to predict phenotype on the basis of genotype alone. © 2016 Wiley Periodicals, Inc.
SETD5 loss‐of‐function mutation as a likely cause of a familial syndromic intellectual disability with variable phenotypic expression
Authors: Szczałuba Krzysztof , Brzezinska Monika , Kot Justyna , Rydzanicz Małgorzata , Walczak Anna , Stawiński Piotr , Werner Bożena , Płoski Rafał
Published: July 2016

Loss‐of‐function de novo mutations in the SETD5 gene, encoding a putative methyltransferase, are an important cause of moderate/severe intellectual disability as evidenced by the results of sequencing large patient cohorts. We present the first familial case of a SETD5 mutation contributing to a phenotype of congenital heart defects and dysmorphic features, with variable expression, in two siblings and their father. Interestingly, the father demonstrated only mild intellectual impairment. Family based exome sequencing combined to careful parental phenotyping may reveal a more complex clinical picture in newly recognized syndromes. © 2016 Wiley Periodicals, Inc.
Vinyl Selenones Derived from d‐Fructose: A New Platform for Fructochemistry
Authors: Bhaumik Atanu , Das Ashrukana , Pathak Tanmaya
Published: July 2016

d‐Fructose, an inexpensive biomass precursor available on a large scale, has been used for the generation of enantiomerically pure chemical entities. Construction of vinyl selenone moieties on cyclic skeletons of d‐fructose led to the highly reactive synthetic intermediates comprising of an electron‐deficient double bond along with an excellent leaving group. Reactions of these Michael acceptors with different nucleophiles afforded aziridines, thiiranes, cyclopropanes, dihydrofurans, dihydroisoxazole, dibenzyloxymethylfuran, and isonucleosides in moderate to good yields. This powerful and practical route provides a new platform for synthetic applications of renewable biomass precursors and adds to the toolbox for chemists interested in new chemical entities.
Light‐Harvesting Nanotubes Formed by Supramolecular Assembly of Aromatic Oligophosphates
Authors: Bösch Caroline D. , Langenegger Simon M. , Häner Robert
Published: July 2016

A 2,7‐disubstituted phosphodiester‐linked phenanthrene trimer forms tubular structures in aqueous media. Chromophores are arranged in H‐aggregates. Incorporation of small quantities of pyrene results in the development of light‐harvesting nanotubes in which phenanthrenes act as antenna chromophores and pyrenes as energy acceptors. Energy collection is most efficient after excitation at the phenanthrene H‐band. Fluorescence quantum yields up to 23 % are reached in pyrene doped, supramolecular nanotubes.
Direct Cross‐Couplings of Propargylic Diols
Authors: Green Nicholas J. , Willis Anthony C. , Sherburn Michael S.
Published: July 2016

[Pd(PPh3)4] catalyzes a Suzuki–Miyaura‐like twofold cross‐coupling sequence between underivatized propargylic diols and either aryl or alkenyl boronic acids to furnish highly substituted 1,3‐dienes. Thus, 2,3‐diaryl‐1,3‐butadienes and their dialkenic congeners ([4]dendralenes) are delivered in a (pseudo)halogen‐free, single‐step synthesis which supersedes existing methods. Allenols are also readily formed. Treatment of these single‐ and twofold cross‐coupled products with acid leads to remarkably short syntheses of highly‐substituted benzofulvenes and aryl indenes, respectively.
Highly Selective Phosphinylphosphination of Alkenes with Tetraphenyldiphosphine Monoxide
Authors: Sato Yuki , Kawaguchi Shin‐ichi , Nomoto Akihiro , Ogawa Akiya
Published: July 2016

In sharp contrast to tetraphenyldiphosphine, which does not add to carbon–carbon double bonds efficiently, its monoxide, [Ph2P(O)PPh2] can engage in a radical addition to various alkenes, thus affording the corresponding 1‐phosphinyl‐2‐phosphinoalkanes regioselectively, and they can be converted into their sulfides by treatment with elemental sulfur. The phosphinylphosphination proceeds by the homolytic cleavage of the PV(O)−PIII single bond of Ph2P(O)PPh2, followed by selective attack of the phosphinyl radical at the terminal position of the alkenes, and selective trapping of the resulting carbon radical by the phosphino group. Furthermore, the phosphinylphosphination product could be converted directly into its platinum complex with a hemilabile P,O chelation.
Formamides as Lewis Base Catalysts in SN Reactions—Efficient Transformation of Alcohols into Chlorides, Amines, and Ethers
Authors: Huy Peter H. , Motsch Sebastian , Kappler Sarah M.
Published: July 2016

A simple formamide catalyst facilitates the efficient transformation of alcohols into alkyl chlorides with benzoyl chloride as the sole reagent. These nucleophilic substitutions proceed through iminium‐activated alcohols as intermediates. The novel method, which can be even performed under solvent‐free conditions, is distinguished by an excellent functional group tolerance, scalability (>100 g) and waste‐balance (E‐factor down to 2). Chiral substrates are converted with excellent levels of stereochemical inversion (99 %→≥95 % ee). In a practical one‐pot procedure, the primary formed chlorides can be further transformed into amines, azides, ethers, sulfides, and nitriles. The value of the method was demonstrated in straightforward syntheses of the drugs rac‐Clopidogrel and S‐Fendiline.
Bisurfactant‐assisted preparation of amorphous silica from fly ash
Authors: Liu Dandan , Fang Li , Cheng Fangqin
Published: July 2016

Amorphous silica (white carbon black) has been prepared via a one‐step hydrochloride acidification of fly ash with the assistance of cetyl‐trimethylammonium bromide (CTAB) and polyethylene glycol (PEG). The effects of surfactant types and their concentration on the properties of amorphous silica have been investigated by X‐ray diffraction (XRD), particle size analysis and dibutyl phthalate (DBP) absorption value measurement. The results show that both the dispersity and hydrophobicity of the prepared silica modified by the mixed surfactants of CTAB and PEG are better than those modified by either CTAB or PEG individually. The particle size and DBP absorption value of the silica products are 3.2 µm and 3.11 cm3 · g−1 at the optimized CTAB concentration of 9 × 10−4 mol · L−1 and PEG dosage of 0.5 wt%, respectively. Consequently, the filtration time for the obtained silica is shortened as little as 3 min. It is worth mentioning that the purity of the products has been improved with the aid of the mixed surfactants. Copyright © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Effect of Potassium Bromate on the Liver of Adult Male Albino Rat and A Possible Protective Role of Vitamin C: Histological, Immunohistochemical, and Biochemical Study
Authors: Bayomy Naglaa A. , Soliman Gehan M. , Abdelaziz Eman Z.
Published: July 2016

Potassium bromate (KBrO3) is a food additive which is used primarily as a maturing agent for flour. It is proved as a toxic agent with significant reduction in the activities of antioxidant capacity. The therapeutic efficacy of vitamin C as antioxidant may provide a possible solution to KBrO3 mediated oxidative damage. Twenty four adult male albino rats were used to evaluate the protective role of vitamin C against KBrO3 induced hepatotoxicity and divided into four groups; Group 1 (control), Group 2: received 30 mg/Kg/day vitamin C orally for 4 weeks, Group 3: received 20 mg/Kg/dose KBrO3 orally twice weekly for 4 weeks and Group 4: received both KBrO3 and vitamin C. Liver specimens were processed for histological study by light and electron microscopes and stained immunohistochemically to detect glial fibriller acidic protein (GFAP). Serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were estimated as well as the levels of malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) activities in all dissected tissues were determined. KBrO3 induced histological alterations in the form of degeneration, cellular infiltration and significant increase in collagen deposition in portal tracts with a significant increase in immunoexpression of GFAP. Significant rise in serum levels of AST, ALT, and MDA in liver tissues were recorded. However, levels of GSH and SOD were significantly decreased. Most of these changes were improved by vitamin C treatment. In conclusion, vitamin C ameliorates the histological and biochemical alterations of the liver induced by KBrO3. Anat Rec, 299:1256–1269, 2016. © 2016 Wiley Periodicals, Inc.
Public transit service operation strategy under indifference thresholds‐based bi‐modal equilibrium
Authors: Wang Wei (Walker) , Wang David Z. W. , Sun Huijun , Wu Jianjun
Published: July 2016

This paper investigates public transit service (fare and frequency) operation strategies in a bi‐modal network with assumption of indifference thresholds‐based travelers' mode choice behavior. Under such behavior, users would switch to a new mode only if its utility is larger than the utility of current mode plus a threshold. The concept of indifference thresholds‐based bi‐modal equilibrium (ITBE) and the properties of the ITBE solution are explicitly proposed. Considering transit operator's different economic objectives (profit‐maximizing, no‐deficit and total system cost‐minimizing), the effect of indifference thresholds on transit fare and frequency schemes is studied. Some numerical experiments are accompanied to verify the theoretical results. Copyright © 2016 John Wiley & Sons, Ltd.
Hierarchical multivariate mixture generalized linear models for the analysis of spatial data: An application to disease mapping
Authors: Torabi Mahmoud
Published: July 2016

Disease mapping of a single disease has been widely studied in the public health setup. Simultaneous modeling of related diseases can also be a valuable tool both from the epidemiological and from the statistical point of view. In particular, when we have several measurements recorded at each spatial location, we need to consider multivariate models in order to handle the dependence among the multivariate components as well as the spatial dependence between locations. It is then customary to use multivariate spatial models assuming the same distribution through the entire population density. However, in many circumstances, it is a very strong assumption to have the same distribution for all the areas of population density. To overcome this issue, we propose a hierarchical multivariate mixture generalized linear model to simultaneously analyze spatial Normal and non‐Normal outcomes. As an application of our proposed approach, esophageal and lung cancer deaths in Minnesota are used to show the outperformance of assuming different distributions for different counties of Minnesota rather than assuming a single distribution for the population density. Performance of the proposed approach is also evaluated through a simulation study.
Polymeric nanoparticle‐based delivery of TRAIL DNA for cancer‐specific killing
Authors: Tzeng Stephany Y. , Wilson David R. , Hansen Sarah K. , Quiñones‐Hinojosa Alfredo , Green Jordan J.
Published: July 2016

Lack of specificity in cancer therapeutics severely limits the efficacy of many existing treatment modalities. The use of Tumor Necrosis Factor‐related Apoptosis‐Inducing Ligand (TRAIL) is of interest to the field due to this protein's ability to cause cell death specifically in cancer cells without harming the surrounding healthy tissue. Here, we report that polymeric nanoparticles, based on synthetic poly(beta‐amino ester)s (PBAEs) and containing DNA, are able to selectively transfect cancer cells in vitro over healthy cells of the same tissue type. Moreover, PBAE‐based nanoparticles containing TRAIL DNA are able to transfect several human cancer cell cultures in vitro and cause cell death. While certain cell types, including human glioblastoma (GBM), showed resistance to TRAIL, we found that the expression of TRAIL‐binding surface proteins was predictive of each cell type's resistance to TRAIL therapy. We demonstrate a non‐viral nanomedicine approach to cancer gene therapy that can improve cancer specificity via both biomaterial selection and through the use of cancer‐targeting genetic cargo.
Mixed Polymer‐Coated Magnetic Nanoparticles as Forward Osmosis Draw Agents of Tuned Hydrophilicity
Authors: Dey Priyanka , Izake Emad L.
Published: July 2016

We recently reported a polymer‐coated magnetic nanoparticle (MNP) draw agent for the forward osmosis (FO) water desalination process. The water flux was found to increase when the polymer poly(sodium acrylate) (PSA) was anchored to the MNP surface as compared to the polymer (or polyelectrolyte solution) alone, due to the polymer chains being stretched out and most of the hydrophilic groups on the polymer contributing to water flux. We herein report the use of a secondary polymer poly(N‐isopropylacrylamide) PNIPAM to manipulate the PSA polymer conformation and influence inter‐ and intrachain interactions to enhance the efficiency of the FO draw agent. These PSA–PNIPAM‐coated MNPs generated a much higher water flux of ∼11.66 LMH when compared to the 100 % PSA‐coated MNPs featuring a value of ∼5.32 LMH under identical FO conditions. The osmotic pressure and water flux driven by the mixed polymer‐coated MNPs were found to be a strong function of the net polymer coverage on MNPs, that is, net available hydrophilic groups. Our new draw agent demonstrates potential for use in the water industry due to its improved efficiency and cost effectiveness as it uses only ∼0.062 % (w/v) of the draw agent solution.
Peracetic Acid Depolymerization of Biorefinery Lignin for Production of Selective Monomeric Phenolic Compounds
Authors: Ma Ruoshui , Guo Mond , Lin Kuan‐ting , Hebert Vincent R. , Zhang Jinwen , Wolcott Michael P. , Quintero Melissa , Ramasamy Karthikeyan K. , Chen Xiaowen , Zhang Xiao
Published: July 2016

Lignin is the largest source of renewable material with an aromatic skeleton. However, due to the recalcitrant and heterogeneous nature of the lignin polymer, it has been a challenge to effectively depolymerize lignin and produce high‐value chemicals with high selectivity. In this study, a highly efficient lignin‐to‐monomeric phenolic compounds (MPC) conversion method based on peracetic acid (PAA) treatment was reported. PAA treatment of two biorefinery lignin samples, diluted acid pretreated corn stover lignin (DACSL) and steam exploded spruce lignin (SESPL), led to complete solubilization and production of selective hydroxylated monomeric phenolic compounds (MPC‐H) and monomeric phenolic acid compounds (MPC‐A) including 4‐hydroxy‐2‐methoxyphenol, p‐hydroxybenzoic acid, vanillic acid, syringic acid, and 3,4‐dihydroxybenzoic acid. The maximized MPC yields obtained were 18 and 22 % based on the initial weight of the lignin in SESPL and DACSL, respectively. However, we found that the addition of niobium pentoxide catalyst to PAA treatment of lignin can significantly improve the MPC yields up to 47 %. The key reaction steps and main mechanisms involved in this new lignin‐to‐MPC valorization pathway were investigated and elucidated.
Detailed Investigation of the Immunodominant Role of O‐Antigen Stoichiometric O‐Acetylation as Revealed by Chemical Synthesis, Immunochemistry, Solution Conformation and STD‐NMR Spectroscopy for Shigella flexneri 3a
Authors: Boutet Julien , Blasco Pilar , Guerreiro Catherine , Thouron Françoise , Dartevelle Sylvie , Nato Farida , Cañada F. Javier , Ardá Ana , Phalipon Armelle , Jiménez‐Barbero Jesús , Mulard Laurence A.
Published: July 2016

Shigella flexneri 3a causes bacillary dysentery. Its O‐antigen has the {2)‐[α‐d‐Glcp‐(1→3)]‐α‐l‐Rhap‐(1→2)‐α‐l‐Rhap‐(1→3)‐[Ac→2]‐α‐l‐Rhap‐(1→3)‐[Ac→6]≈40 %‐β‐d‐GlcpNAc‐(1→} ([(E)ABAcCAcD]) repeating unit, and the non‐O‐acetylated equivalent defines S. flexneri X. Propyl hepta‐, octa‐, and decasaccharides sharing the (E′)A′BAcCD(E)A sequence, and their non‐O‐acetylated analogues were synthesized from a fully protected BAcCD(E)A allyl glycoside. The stepwise introduction of orthogonally protected mono‐ and disaccharide imidate donors was followed by a two‐step deprotection process. Monoclonal antibody binding to twenty‐six S. flexneri types 3a and X di‐ to decasaccharides was studied by an inhibition enzyme‐linked immunosorbent assay (ELISA) and STD‐NMR spectroscopy. Epitope mapping revealed that the 2C‐acetate dominated the recognition by monoclonal IgG and IgM antibodies and that the BAcCD segment was essential for binding. The glucosyl side chain contributed to a lesser extent, albeit increasingly with the chain length. Moreover, tr‐NOESY analysis also showed interaction but did not reveal any meaningful conformational change upon antibody binding.
Highly Efficient Triplet Photosensitizers: A Systematic Approach to the Application of IrIII Complexes containing Extended Phenanthrolines
Authors: Lu Yue , McGoldrick Niamh , Murphy Frances , Twamley Brendan , Cui Xiaoneng , Delaney Colm , Máille Gearóid M. Ó , Wang Junsi , Zhao Jianzhang , Draper Sylvia M.
Published: July 2016

A series of IrIII complexes, based on 1,10‐phenanthroline featuring aryl acetylene chromophores, were prepared and investigated as triplet photosensitizers. The complexes were synthesized by Sonogashira cross‐coupling reactions using a “chemistry‐on‐the‐complex” method. The absorption properties and luminescence lifetimes were successfully tuned by controlling the number and type of light‐harvesting group. Intense UV/Vis absorption was observed for the IrIII complexes with two light‐harvesting groups at the 3‐ and 8‐positions of the phenanthroline. The asymmetric IrIII complex (with a triphenylamine (TPA) and a pyrene moiety attached) exhibited the longest lifetime. Red emission was observed for all the complexes in deaerated solutions at room temperature. Their emission at low temperature (77 K) and nanosecond time‐resolved transient difference absorption spectra revealed the origin of their triplet excited states. The singlet‐oxygen (1O2) sensitization and triplet‐triplet annihilation (TTA)‐based upconversion were explored. Highly efficient TTA upconversion (ΦUC=28.1 %) and 1O2 sensitization (ΦΔ=97.0 %) were achieved for the asymmetric IrIII complex, which showed intense absorption in the visible region (λabs=482 nm, ϵ=50900 m−1 cm−1) and had a long‐lived triplet excited state (53.3 μs at RT).
Isolation, Stereochemical Study, and Antioxidant Activity of Benzofuranone Derivatives from a Mangrove‐derived Fungus Eurotium rubrum MA‐150
Authors: Meng Ling‐Hong , Mándi Attila , Li Xiao‐Ming , Liu Yang , Kurtán Tibor , Wang Bin‐Gui
Published: July 2016

Enantiomers of a 2‐benzofuran‐1(3H)‐one derivative [(–)‐1 and (+)‐1] and four known analogs (2, 3, 4, 5) were isolated and identified from the culture extract of Eurotium rubrum MA–150, a fungus obtained from the mangrove‐derived rizospheric soil. Their structures were established by detailed interpretation of nuclear magnetic resonance (NMR) data and the structure of (±)‐1 was confirmed by single‐crystal X‐ray diffraction analysis. The absolute configuration of the enantiomers (–)‐1 and (+)‐1 was determined by means of online high‐performance liquid chromatography – electronic circular dichroism (HPLC‐ECD) measurements and time‐dependent Density Functional Theory – electronic circular dichroism (TDDFT‐ECD) calculations. Compounds (±)‐1 as well as 2 and 3 exhibited potent DPPH radical scavenging activities with IC50 values of 1.23, 2.26, and 3.99 μg/mL, respectively. Chirality 28:581–584, 2016. © 2016 Wiley Periodicals, Inc.
Variable selection for frailty transformation models with application to diabetic complications
Authors: Liu Xu , Song Xinyuan , Xie Shangyu , Zhou Yong
Published: July 2016

This article focuses on variable selection in the context of gamma frailty transformation models for multivariate survival times. We propose a method based on a nonconcave penalty function to select relevant regression predictors and simultaneously estimate model parameters and nonparametric functions. Our procedure performs as well as the oracle one in which the true model is assumed to be known. We conduct simulation studies to demonstrate the performance of the proposed methodology. We apply our method to a case study based on the Hong Kong Diabetes Registry, and obtain new insights on the risk factors of cardiovascular–renal complications for type 2 diabetic patients.The Canadian Journal of Statistics44: 375–394; 2016 © 2016 Statistical Society of Canada
Visualization of Dust Particle Data with Plasma Simulation Results Using Virtual‐Reality System
Authors: Ohtani H. , Shoji M. , Ohno N. , Suzuki Y. , Ishiguro S. , Kageyama A. , Tamura Y.
Published: July 2016

We develop the environment in which the time‐sequence experimental data of three‐dimensional dust particle positions observed by the stereoscopic fast framing cameras is visualized in one virtual‐reality space with the results of the equilibrium plasma simulation in the vessel device data integrally using a virtual‐reality system. Since their three‐dimensional relative positions can be displayed, it is possible to analyze the three‐dimensional relationship between the dust trajectories, the magnetic‐field structure, and the devices in the vessel. It is confirmed that the observed dust particles are distributed in the periphery region. Most dusts move along the magnetic‐field line, but some particles move radially across the lines with sharply curved trajectories. The transport direction varies from place to place. This system promoted the viewers' understanding. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Model of Self‐similar Radiative Transfer in Resonance Lines for Testing the Edge Plasma Codes
Authors: Sdvizhenskii P. A. , Krasheninnikov S. I. , Kukushkin A. B.
Published: July 2016

Possibilities of obtaining the analytical solutions of the one‐dimensional equation of radiative transfer in resonance atomic/ionic lines in the Biberman‐Holstein model for testing the edge plasma codes are investigated. It is shown that for some types of similarity of spatial profiles of three characteristics, namely, background plasma density, line shape width and non‐radiation source of atomic excitation, the profile of excited atoms density may be described analytically in terms of the similarity of the above‐mentioned profiles. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation Analysis of Carbon Deposition Profile in the Closed Helical Divertor Configuration in the Large Helical Device
Authors: Shoji M. , Kawamura G. , Tanaka H. , Watanabe I. , Kobayashi M. , Tokitani M. , Masuzaki S. , LHD Experiment Group
Published: July 2016

Recent long pulse plasma discharges in the Large Helical Device have been interrupted by radiation collapse induced by large amounts of dusts released from a closed divertor region. Traces of exfoliation of carbon‐rich mixed material deposition layers were found in the divertor region after the experimental campaigns, indicating that the thickly accumulated deposited layers were exfoliated and broken into dusts. Simulation of the density profiles of carbon deposition in the divertor region by EMC3‐EIRENE reasonably explains the observation of the exfoliation of the deposition layers. It shows that the positions of the exfoliated layers correspond to the area where the density of the carbon deposition is high. It also proves that change of the configuration of target plates in the closed divertor is effective for controlling the accumulation of the carbon deposition, and carbon atoms released from the new target plates does not influence the main plasma confinement region. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of Classical and Neo‐classical Cross‐field Transport of Tungsten Impurity in Realistic Tokamak Geometry
Authors: Yamoto S. , Homma Y. , Inoue H. , Sawada Y. , Hoshino K. , Hatayama A. , Bonnin X. , Coster D. , Schneider R.
Published: July 2016

The initial simulation study of the neoclassical perpendicular self‐diffusion transport in the SOL/Divertor regions for a realistic tokamak geometry with the IMPGYRO code has been performed in this paper. One of the most unique features of the IMPGYRO code is calculating exact Larmor orbit of the test particle instead of assuming guiding center approximation. Therefore, effects of the magnetic drifts in realistic tokamaks are naturally taken into account in the IMPGYRO code. This feature makes it possible to calculate neoclassical transport processes, which possibly become large in the SOL/divertor plasma. Indeed, neoclassical self‐diffusion process, the resultant effect of the combination of magnetic drift and Coulomb collisions with background ions, has already been included in the IMPGYRO model. In the present paper, prior to implementing the detailed model of neoclassical transport process into IMPGYRO, we have investigated the effect of neoclassical selfdiffusion in a realistic tokamak geometry with lower single null X‐point. We also use a model with guiding center approximation in order to compare with the IMPGYRO full orbit model. The preliminary calculation results of each model have shown differences in the perpendicular average velocity of impurity ions at the top region of the SOL. The mechanism which leads to the difference has been discussed. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Maternal separation increases later immobility during forced swim in guinea pig pups: evidence for sensitization of a depressive‐like state
Authors: Hennessy Michael B. , Schreibeis Amanda D. , Schiml Patricia A. , Deak Terrence
Published: July 2016

Early‐life stress is thought to increase later vulnerability for developing depressive illness by sensitizing underlying stress‐responsive systems. Guinea pig pups separated from their mother and isolated in a novel cage for 3 hr exhibit a sensitized depressive‐like behavioral response when separated again the following day as well as weeks later. The behavioral response and its sensitization appear to be mediated by inflammatory factors. To determine if this sensitization is specific to the separation response or if it reflects a broader underlying depressive‐like state, guinea pig pups that had either been separated for 3 hr or remained with their mothers were observed in the forced swim test the following 3 days. Earlier separation was found to increase the duration of immobility, a measure sensitive to antidepressant treatment. These results support the use of the guinea pig as a model for examining mechanisms of inflammatory‐mediated sensitization of depression following stress in early life.
Liquid chromatography‐quadrupole‐time‐of‐flight mass spectrometry screening procedure for urine samples in forensic casework compared to gas chromatography‐mass spectrometry
Authors: Fels Helena , Dame Torsten , Sachs Hans , Musshoff Frank
Published: July 2016

This work represents the development, validation, and application of a liquid chromatography‐quadrupole‐time‐of‐flight mass spectrometry (LC‐QTOF‐MS) screening method for the detection of pharmaceutical substances and illicit drugs (acidic, basic, and neutral organic drugs) in urine samples. Time‐of‐flight mass spectrometry was performed using an LC‐Triple TOF 5600 system with electrospray ionization operated in both positive and negative mode, respectively. The limits of detection (LODs), determined for 34 substances, were < 10 ng/mL for 91% of the compounds. The limits of quantitation (LOQs) were < 20 ng/mL for 91% of the substances. The identification of the compounds was based on exact mass (< ± 5 ppm), retention time (<2%) if available, isotopic pattern fit (<10%) and library hit (>70%). These four parameters served as identification criteria and are discussed according to their role in identifying compounds even without reference substances. In routine casework, two in‐house XIC (extracted ion chromatogram) lists, consisting of 456 protonated and 26 deprotonated compounds were used and retention times for 365 compounds were available. Compared to the results found with the established gas chromatography‐mass spectrometry (GC‐MS) procedure, the findings with the LC‐QTOF‐MS screening method showed a good comparability. Results that were not detected by LC‐QTOF‐MS because of a missing entry in the targeted XIC list could retrospectively be confirmed by simply entering the elemental formula of the relevant substance into the software and reprocessing the sample. LC‐QTOF‐MS offers an attractive technique for the fast and specific identification of illicit drugs and toxic compounds in urine samples. Copyright © 2016 John Wiley & Sons, Ltd.
Enhanced Antitumor Activity against Melanoma Cancer Cells by Nitric Oxide Release and Photosensitized Generation of Singlet Oxygen from Ruthenium Complexes
Authors: Ramos Loyanne C. B. , Marchesi Mario Sérgio Pereira , Callejon Daniel , Baruffi Marcelo Dias , Lunardi Claure N. , Slep Leonardo D. , Bendhack Lusiane M. , da Silva Roberto Santana
Published: July 2016

We have investigated the synergistic effect of nitric oxide and singlet oxygen originating from stimulated ruthenium complexes and their photodynamic action against a melanoma cancer cell line. In aqueous solution, the photosensitizer [Ru(NH3)5pz]2+ (I; pz = pyrazine) and the nitrosylruthenium complex trans‐[RuCl([15]aneN4)NO]2+ (II; [15]aneN4 = 1,4,8,12‐tetrazacyclopentadecane) can produce singlet oxygen and nitric oxide, respectively. The phototoxicity of complex I does not correlate with the singlet oxygen quantum yields unless it is mediated by nitric oxide release from complex II. This effect is around 70 and 50 % higher than the effect prompted by compounds I and II, respectively, in isolation in the presence of light. It was found that the number of hypodiploid cells in the melanoma cancer cells increased, which indicates that a mixture of compounds I and II induces apoptosis of tumorigenic cell lines. Both singlet oxygen and nitric oxide produced by the ruthenium complexes enhance the photodynamic efficacy in melanoma cancer cells.
Silylosmium Anions for the Synthesis of Borylosmium(II) Complexes by Salt Elimination
Authors: Braunschweig Holger , Légaré Marc‐André , Matler Alexander , Wennemann Benedikt
Published: July 2016

Osmium anionic complexes, K[(PMe3)Os(CO)3(SiR3)] (R = Me, Et), were synthesized by deprotonation of the corresponding metal hydrides. The nucleophilicity of these compounds was demonstrated through the reaction of K[(PMe3)Os(CO)3(SiMe3)] with Cl2BDur and Br2BDur (Dur = 2,3,5,6‐tetramethylphenyl) to give haloboryl complexes through a salt elimination process that is unprecedented for osmium–boron chemistry.
Synthesis and Structural Characterization of Mono‐ and Bimetallic Rhodium(I), Iridium(I) and Gold(I) Methanide and Methandiide Complexes from 2‐Quinolyl‐Linked (Thiophosphoranyl)methane
Authors: Leung Wing‐Por , Chan Yuk‐Chi , Choi Tsz‐Hei , Lee Hung‐Kay
Published: July 2016

The synthesis and structural characterization of RhI, IrI and AuI metal complexes derived from 2‐quinolyl‐linked (thiophosphoranyl)methane CH2(iPr2P=S)(C9H6N‐2) (A) are reported. Metathesis reactions of 2‐quinolyl‐thiophosphinoyl potassium complex [K{CH(iPr2P‐S)(C9H6N‐2)}]n (1) with 1 equiv. of [MCl(COD)]2 (M = Rh, Ir; COD = cycloocta‐1,5‐diene) afforded monomeric 2‐quinolyl‐thiophosphinoyl‐rhodium(I) and iridium(I) complex [M(COD){CH(iPr2P=S)(C9H6N‐2)}] {M = Rh (2), Ir (3)}, respectively. Upon treatment of 1 with 2 equiv. of [MCl(COD)]2 (M = Ir, Rh), bimetallic complexes [M(COD){CH(iPr2P=S)(C9H6N‐2)(M(COD)Cl)}] {M = Rh (4), Ir (5)} were obtained. The reaction of 1 with [AuCl(PPh3)] afforded a geminal dinuclear gold(I) methandiide complex [{Au(PPh3)}2{C(iPr2P‐S)(C9H6N‐2)}] (6), featuring an aurophilic interaction. Meanwhile, the metathesis reaction of 1 with 1 equiv. of gold(I) complex [AuCl(IPrNHC)] {IPrNHC = C[N(2,6‐iPr2C6H3)CH]2} afforded a monomeric two‐coordinate monoaurated product, 2‐quinolyl‐thiophosphinoyl‐gold(I) N‐heterocyclic carbene complex [Au(IPrNHC){CH(iPr2P‐S)(C9H6N‐2)}] (7). The structures of 3–7 have been determined by X‐ray crystallography and the UV/Vis absorption properties of 2–6 have also been studied.
Intracell Hydrogen Adsorption–Transmission in a Co2P Solid Hydrogen‐Storage Material
Authors: Bao Di , Gao Peng , Li Chenliang , Wu Guoxun , Wang Yanbo , Chen Yujin , Zhou Han , Yang Piaoping
Published: July 2016

Co2P nanoparticles, obtained by a simple mechanical ball‐milling treatment, have been shown to undergo a new hydrogen adsorption–transmission process called intracell Kubas‐enhanced adsorption, which results in an improved hydrogen‐storage capacity. It is found that in this intracell Kubas‐enhanced adsorption process hydrogen is firstly adsorbed by the Co atoms in Co2P through a Co···H interaction and activated. It is then spilt over to the P atoms in Co2P accompanied by the formation of a P–H bond, which has a lower bonding energy. This adsorption–transmission process is unambiguously proved by a detailed analysis of X‐ray photoelectron spectroscopy (XPS), X‐ray powder diffraction (XRD), cyclic voltammetry (CV), and quantum chemical calculation results.
1,1‐ and 1,4‐Addition Reactions with 3a,6a‐Diaza‐1,4‐diphosphapentalene Containing Two‐Coordinate and Formally Divalent Phosphorus
Authors: Kornev Alexander N. , Galperin Vadim E. , Sushev Vyacheslav V. , Zolotareva Natalia V. , Baranov Evgenii V. , Fukin Georgy K. , Abakumov Gleb A.
Published: July 2016

3a,6a‐Diaza‐1,4‐diphosphapentalene (DDP) reacts with halocarbons to give addition products to one or both phosphorus atoms depending on the substrate. Chlorotriphenylmethane affords a 1,4‐addition product, which slowly decomposes in solution to form the Ph3C radical and the chloro‐DDP coupling product with a P–P bond. Benzyl chloride is added to one phosphorus atom to form hypervalent (trivalent, four‐coordinate) phosphorus with a N···P distance (nonvalent interaction) of 2.191(2) Å. A workup of the latter with GeCl2 results in a complex salt containing the GeCl3– anion and cation with covalent N–P bonding.