bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct prediction of spatially and temporally varying physical properties from time‐lapse electrical resistance data
Authors: Hermans Thomas , Oware Erasmus , Caers Jef
Published: September 2016

Time‐lapse applications of electrical methods have grown significantly over the last decade. However, the quantitative interpretation of tomograms in terms of physical properties, such as salinity, temperature or saturation, remains difficult. In many applications, geophysical models are transformed into hydrological models, but this transformation suffers from spatially and temporally varying resolution resulting from the regularization used by the deterministic inversion. In this study, we investigate a prediction‐focused approach (PFA) to directly estimate subsurface physical properties with electrical resistance data, circumventing the need for classic tomographic inversions. First, we generate a prior set of resistance data and physical property forecast through hydrogeological and geophysical simulations mimicking the field experiment. We reduce the dimension of both the data and the forecast through principal component analysis in order to keep the most informative part of both sets in a reduced dimension space. Then, we apply canonical correlation analysis to explore the relationship between the data and the forecast in their reduced dimension space. If a linear relationship can be established, the posterior distribution of the forecast can be directly sampled using a Gaussian process regression where the field data scores are the conditioning data. In this paper, we demonstrate PFA for various physical property distributions. We also develop a framework to propagate the estimated noise level in the reduced dimension space. We validate the results by a Monte Carlo study on the posterior distribution and demonstrate that PFA yields accurate uncertainty for the cases studied.
Predicting cyberbullying perpetration in emerging adults: A theoretical test of the Barlett Gentile Cyberbullying Model
Authors: Barlett Christopher , Chamberlin Kristina , Witkower Zachary
Published: September 2016

The Barlett and Gentile Cyberbullying Model (BGCM) is a learning‐based theory that posits the importance of positive cyberbullying attitudes predicting subsequent cyberbullying perpetration. Furthermore, the tenants of the BGCM state that cyberbullying attitude are likely to form when the online aggressor believes that the online environment allows individuals of all physical sizes to harm others and they are perceived as anonymous. Past work has tested parts of the BGCM; no study has used longitudinal methods to examine this model fully. The current study (N = 161) employed a three‐wave longitudinal design to test the BGCM. Participants (age range: 18–24) completed measures of the belief that physical strength is irrelevant online and anonymity perceptions at Wave 1, cyberbullying attitudes at Wave 2, and cyberbullying perpetration at Wave 3. Results showed strong support for the BGCM: anonymity perceptions and the belief that physical attributes are irrelevant online at Wave 1 predicted Wave 2 cyberbullying attitudes, which predicted subsequent Wave 3 cyberbullying perpetration. These results support the BGCM and are the first to show empirical support for this model. Aggr. Behav. 43:147–154, 2017. © 2016 Wiley Periodicals, Inc.
Quasi‐Static Compression Properties and Failure of PTFE/Al/W Reactive Materials
Authors: Xu Feng Yue , Liu Shu Bo , Zheng Yuan Feng , Yu Qing Bo , Wang Hai Fu
Published: September 2016

Quasi‐static compression experiments are performed on two kinds of the PTFE/Al/W reactive material specimens, fabricated by means of the cold isostatic pressing but not sintering or the pressing followed by sintering, respectively. The results show that, compared with the pressed specimens, the sintered specimens show higher failure stress and greater fracture toughness. Moreover, the mesoscale failure behaviors are significantly influenced by the sintering technique and the component ratios. There are significantly different bonding and dispersion type of the PTFE matrix between the pressed specimen and the sintered specimen, resulting in the differences of mechanical properties and failure behavior between the two kinds of specimens.
Modulation of Mechanical Interactions by Local Piezoelectric Effects
Authors: Brown Cameron P. , Boyd Jennifer L. , Palmer Antony J. , Phillips Mick , Couture Charles‐Andre , Rivard Maxime , Hulley Philippa A. , Price Andrew J. , Ruediger Andreas , Légaré Francois , Carr Andrew J.
Published: September 2016

Piezoelectricity is a well‐established property of biological materials, yet its functional role has remained unclear. Here, a mechanical effect of piezoelectric domains resulting from collagen fibril organisation is demonstrated, and its role in tissue function and application to material design is described. Using a combination of scanning probe and nonlinear optical microscopy, a hierarchical structuring of piezoelectric domains in collagen‐rich tissues is observed, and their mechanical effects are explored in silico. Local electrostatic attraction and repulsion due to shear piezoelectricity in these domains modulate fibril interactions from the tens of nanometre (single fibril interactions) to the tens of micron (fibre interactions) level, analogous to modulated friction effects. The manipulation of domain size and organisation thus provides a capacity to tune energy storage, dissipation, stiffness, and damage resistance.
Hole‐Programmed Superfast Multistep Folding of Hydrogel Bilayers
Authors: Stoychev Georgi , Guiducci Lorenzo , Turcaud Sébastien , Dunlop John W. C. , Ionov Leonid
Published: September 2016

Two important aspects of actuation behavior of stimuli‐responsive hydrogels are the complexity of the shape change and its speed. Here, it is shown that varying the shape of simple polymer bilayers can result in very complex and very fast spontaneous folding. The complexity and high folding rate arise from the choice of the shape and from the presence of inhomogeneous swelling within the thermoresponsive layer entrapped between the top hydrophobic layer and the substrate. In contrast to homogeneous swelling of a freestanding bilayer, which leads to a gradual increase of curvature throughout the whole bilayer, inhomogeneous swelling first results in complete rolling of the periphery of the film, which changes its mechanical properties and affects the subsequent morphing process. Further swelling of the thermoresponsive layer generates more stress that builds up until a buckling threshold is overcome, allowing very fast switching from the flat edge‐rolled configuration into a folded one. The research demonstrates how the introduction of holes into actuating bilayers gives rise not only to a novel geometric control over the folding fate of the films but also adds the ability to tune the rate of folding, through the careful selection of hole size, location, and shape.
Diketopyrrolopyrrole Organic Thin‐Film Transistors: Impact of Alkyl Substituents and Tolerance of Ethylhexyl Stereoisomers
Authors: Stolte Matthias , Suraru Sabin‐Lucian , Diemer Patricia , He Tao , Burschka Christian , Zschieschang Ute , Klauk Hagen , Würthner Frank
Published: September 2016

Bis(thiophen‐2‐yl)‐diketopyrrolopyrrole (DPP) dyes bearing various alkyl substituents at the amide positions (n‐butyl, n‐pentyl, n‐hexyl, n‐heptyl, n‐octyl, 2‐ethylhexyl) and chlorine (Cl), bromine (Br), or cyano (CN) substituents at the thiophene positions have been synthesized and investigated with regard to their molecular and semiconducting properties. Intense absorption, strong fluorescence, and reversible oxidation and reduction processes are common to all of these dyes. Their characterization as organic semiconductors in vacuum‐processed thin‐film transistors reveals p‐channel operation with field‐effect mobilities ranging from 0.01 to 0.7 cm2 V−1 s−1. The highest mobility is found for the DPP dyes bearing the 2‐ethylhexyl substituents, which is surprising, considering that as a result of the chiral substituents, this material is a mixture of (R,R), (S,S), and (R,S) stereoisomers. The high carrier mobility in the films of the DPPs bearing stereoisomerically inhomogeneous ethylhexyl groups is rationalized here by single‐crystal X‐ray diffraction (XRD) analysis in combination with XRD and atomic force microscopy studies on thin films, which reveal the presence of slightly different 2D layer arrangements for the n‐alkyl and the 2‐ethylhexyl derivatives. For the cyano‐substituted DPPs possessing the lowest LUMO levels, ambipolar transport characteristics are observed.
Effective Codelivery of lncRNA and pDNA by Pullulan‐Based Nanovectors for Promising Therapy of Hepatocellular Carcinoma
Authors: Ren Yanli , Li Rui‐Quan , Cai Yi‐Ran , Xia Tian , Yang Ming , Xu Fu‐Jian
Published: September 2016

Hepatocellular carcinoma (HCC) is one of the most common cancers. Maternally expressed gene 3 (MEG3, one kind of long noncoding RNA [lncRNA]) can act as a tumor suppressor and regulate P53 target gene expression. However, lncRNA MEG3 demonstrates relatively low or no expression in human HCC. This study provides a promising concept to codeliver lncRNA and pDNA for cancer therapy. As proof‐of‐concept, the pcDNA‐MEG3 and pcDNA‐P53 plasmids‐condensed nanocomplexes with the liver‐targeting polycation gene vector, pullulan‐based ethanolamine‐modified poly(glycidyl methacrylate) (denoted as PuPGEA), are proposed to codeliver lncRNA and pDNA to treat HCC. Pullulan‐containing nanovectors are shown to be able to effectively mediate gene delivery in liver cells. To assess gene delivery performances of PuPGEA, a series of assays such as in vitro gene transfection, HCC cell proliferation, colony formation, migration, matrigel transwell assays, and in vivo xenograft animal models are carried out. The codelivery system with PuPGEA/(MEG3+P53) nanocomplexes demonstrates additive effects in suppressing HCC compared to PuPGEA/MEG3 or PuPGEA/P53 nanocomplexes alone. These results suggest that codelivery of lncRNA and pDNA by polycation nanovectors is a promising method to treat cancers.
Ultra‐High Surface Area Activated Porous Asphalt for CO2 Capture through Competitive Adsorption at High Pressures
Authors: Jalilov Almaz S. , Li Yilun , Tian Jian , Tour James M.
Published: September 2016

This study reports an improved method for activating asphalt to produce ultra‐high surface area porous carbons. Pretreatment of asphalt (untreated Gilsonite, uGil) at 400 °C for 3 h removes the more volatile organic compounds to form pretreated asphalt (uGil‐P) material with a larger fraction of higher molecular weight π‐conjugated asphaltenes. Subsequent activation of uGil‐P at 900 °C gives an ultra‐high surface area (4200 m2 g−1) porous carbon material (uGil‐900) with a mixed micro and mesoporous structure. uGil‐900 shows enhanced room temperature CO2 uptake capacity at 54 bar of 154 wt% (35 mmol g−1). The CH4 uptake capacity is 37.5 wt% (24 mmol g−1) at 300 bar. These are relevant pressures in natural gas production. The room temperature working CO2 uptake capacity for uGil‐900 is 19.1 mmol g−1 (84 wt%) at 20 bar and 32.6 mmol g−1 (143 wt%) at 50 bar. In order to further assess the reliability of uGil‐900 for CO2 capture at elevated pressures, the authors study competitive sorption of CO2 and CH4 on uGil‐900 at pressures from 1 to 20 bar at 25 °C. CO2/CH4 displacement constants are measured at 2 to 40 bar, and found to increase significantly with pressure and surface area.
Investigating the Role of 4‐Tert Butylpyridine in Perovskite Solar Cells
Authors: Habisreutinger Severin N. , Noel Nakita K. , Snaith Henry J. , Nicholas Robin J.
Published: September 2016

The majority of hole‐transporting layers used in n‐i‐p perovskite solar cells contain 4‐tert butylpyridine (tBP). High power‐conversion efficiencies and, in particular, good steady‐state performance appears to be contingent on the inclusion of this additive. On the quest to improve the steady state efficiencies of the carbon nanotube‐based hole‐transporter system, this study has found that the presence of tBP results in an extraordinary improvement in the performance of these devices. By deconstructing a prototypical device and investigating the effect of tBP on each individual layer, the results of this study indicate that this performance enhancement must be due to a direct chemical interaction between tBP and the perovskite material. This study proposes that tBP serves to p‐dope the perovskite layer and investigates this theory with poling and work function measurements.
Modeling Thermochemical Solar‐to‐Fuel Conversion: CALPHAD for Thermodynamic Assessment Studies of Perovskites, Exemplified for (La,Sr)MnO3
Authors: Bork Alexander H. , Povoden‐Karadeniz Erwin , Rupp Jennifer L. M.
Published: September 2016

Two‐step solar thermochemical fuel production has the potential to reduce global greenhouse gas emissions and replace fossil fuels. The success of the technology relies on the development of materials with high thermochemical efficiency. Perovskites with the general structure ABO3 have received much attention recently due to impressive fuel productivity and their amenability of substituting and doping both A‐ and B‐site. Despite the potential of perovskites for solar‐to‐fuel conversion, literature on their solar thermochemical efficiency is scarce and finding the best chemical composition and optimum operation conditions is unknown. For this purpose, this study suggests to use Computer Coupling of Phase Diagrams and Thermochemistry (CALPHAD) data libraries to access the relevant thermodynamic properties of perovskites. This work demonstrates the usefulness of employing CALPHAD data by a full thermodynamic study of the model case compositions of La1–xSrxMnO3–δ. This study uses data on oxygen‐nonstoichiometry and heat capacity in the temperature range of 1073–1873 K relevant for solar‐to‐fuel. Unlike earlier thermodynamic assessments of perovskites that rely on a single literature source and a limited temperature range, the CALPHAD approach takes all available data in literature into consideration. Thermochemical equilibrium models of fuel yields are accompanied by validations toward experimental results in literature, and this study highlights the effects of strontium doping level on the efficiency.
An Ultrathin Flexible Single‐Electrode Triboelectric‐Nanogenerator for Mechanical Energy Harvesting and Instantaneous Force Sensing
Authors: Chen Shu Wen , Cao Xia , Wang Ning , Ma Long , Zhu Hui Rui , Willander Magnus , Jie Yang , Wang Zhong Lin
Published: September 2016

The trends in miniaturization of electronic devices give rise to the attention of energy harvesting technologies that gathers tiny wattages of power. Here this study demonstrates an ultrathin flexible single electrode triboelectric nanogenerator (S‐TENG) which not only could harvest mechanical energy from human movements and ambient sources, but also could sense instantaneous force without extra energy. The S‐TENG, which features an extremely simple structure, has an average output current of 78 μA, lightening up at least 70 LEDs (light‐emitting diode). Even tapped by bare finger, it exhibits an output current of 1 μA. The detection sensitivity for instantaneous force sensing is about 0.947 μA MPa−1. Performances of the device are also systematically investigated under various motion types, press force, and triboelectric materials. The S‐TENG has great application prospects in sustainable wearable devices, sustainable medical devices, and smart wireless sensor networks owning to its thinness, light weight, energy harvesting, and sensing capacities.
Pinch‐based shortcut method for the conceptual design of adiabatic absorption columns
Authors: Redepenning Christian , Marquardt Wolfgang
Published: September 2016

Shortcut methods are valuable tools for the fast evaluation of key performance indicators in the early phase of conceptual process design. For the design of absorption columns, operation at minimum solvent demand represents a thermodynamically sound indicator, which is, however, difficult to determine because an infinite number of separation stages need to be considered. Instead, the suggested shortcut model exploits the existence of the pinch point to identify operation at minimum solvent demand. Existing shortcut concepts, such as the well‐known equation of Kremser (Natl Pet News, 22, 43–49, 1930), are significantly outperformed by the novel shortcut model, which can be gradually refined to any desired accuracy. Integration into a stepwise procedure results in reliable solutions. The model covers rigorous thermodynamics; no simplifications regarding phase equilibrium, heat effects, or number of components are required. The performance of the method is illustrated by several case studies with up to seven components. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1213–1225, 2017
The neuropsychological function of children with achondroplasia
Authors: Wigg Kimberley , Tofts Louise , Benson Suzanne , Porter Melanie
Published: September 2016

The current observational study had three specific objectives: (i) to document any neuropsychological impairment in a sample of children with achondroplasia; (ii) to explore individual variability; and (iii) to determine the functional impact of any impairments. Fourteen children aged between 6 and 15 years with a medically confirmed diagnosis of achondroplasia (FGFR 3 mutation positive) underwent a comprehensive standardized neuropsychological evaluation. On average, while generally still within normal limits, significantly lower scores compared to standardized means were identified on: Full‐scale IQ, verbal IQ, working memory, arithmetic, attention, executive functioning and aspects of day‐to‐day emotional, social, and behavioral functioning. Clinically significant levels of impairment at a group level were identified on measures of: arithmetic, attention, and executive functioning. There was variability among the group and for most measures scores ranged from impaired to within normal limits. A high percentage of children were impaired on measures of: verbal IQ, attention and executive functioning. Results of this study suggest a need for individual neuropsychological evaluation and monitoring of children with achondroplasia and suggest verbal IQ, arithmetic, attention, and executive functioning are particularly common areas of impairment. © 2016 Wiley Periodicals, Inc.
Unusual X‐chromosome inactivation pattern in patients with Xp11.23‐p11.22 duplication: Report and review
Authors: Di‐Battista Adriana , Meloni Vera Ayres , da Silva Magnus Dias , Moysés‐Oliveira Mariana , Melaragno Maria Isabel
Published: September 2016

In females carrying structural rearrangements of an X‐chromosome, cells with the best dosage balance are preferentially selected, frequently resulting in a skewed inactivation pattern and amelioration of the phenotype. The Xp11.23‐p11.22 region is involved in a recently described microduplication syndrome associated with severe clinical consequences in males and females, causing intellectual disability, behavior problems, epilepsy with electroencephalogram anomalies, minor facial anomalies, and early onset of puberty. Female carriers usually present an unusual X‐chromosome inactivation pattern in favor of the aberrant chromosome, resulting in functional disomy of the duplicated segment. Here, we describe a girl carrying a de novo ∼9.7 Mb Xp11.3‐p11.22 duplication of paternal origin and skewed X‐chromosome inactivation pattern of the normal X‐chromosome. We reviewed other cases previously reported and determined the minimal critical region possibly responsible for this unusual inactivation pattern. The critical region encompasses 36 RefSeq genes, including at least 10 oncogenes and/or genes related to the cell cycle control. We discuss the molecular mechanisms that underlie the positive selection of the cells with the active duplicated chromosome. © 2016 Wiley Periodicals, Inc.
Oxygen‐Rich 1,2,4‐Triazolo[3,4‐d]‐1,2,4‐triazolo[3,4‐f]furazano[3,4‐b]pyrazines as Energetic Materials
Authors: Sheremetev Aleksei B. , Korolev Vecheslav L. , Potemkin Aleksandr A. , Aleksandrova Natali S. , Palysaeva Nadezhda V. , Hoang Trung H. , Sinditskii Valery P. , Suponitsky Kyrill Yu.
Published: September 2016

A convenient one‐pot synthesis of 5,10‐bis(trinitromethyl)‐ (5) and 5,10‐bis(fluorodinitromethyl)furazano[3,4‐e]di([1,2,4]triazolo)[4,3‐a:3′,4′‐c]pyrazines (6) by employing the reaction of 5,6‐dichlorofurazano[3,4‐b]pyrazine with 5‐(trinitromethyl)‐ and 5‐(1‐fluoro‐1,1‐dinitromethyl)tetrazoles, respectively, was developed. The protocol was carried out under mild conditions at a moderate temperature and over short reaction times to synthesize the products in excellent yields. For the first time, these polynitromethyl‐substituted compounds, which may have potential use as explosive and propellant materials, have been fully characterized. The burning rate of compound5was shown to be slightly superior to that of 2,4,6,8,10,12‐hexanitrohexaazaisowurtzitane (CL‐20).
Ultraviolet Photodissociation Induced by Light‐Emitting Diodes in a Planar Ion Trap
Authors: Holden Dustin D. , Makarov Alexander , Schwartz Jae C. , Sanders James D. , Zhuk Eugene , Brodbelt Jennifer S.
Published: September 2016

The first application of light‐emitting diodes (LEDs) for ultraviolet photodissociation (UVPD) mass spectrometry is reported. LEDs provide a compact, low cost light source and have been incorporated directly into the trapping cell of an Orbitrap mass spectrometer. MS/MS efficiencies of over 50 % were obtained using an extended irradiation period, and UVPD was optimized by modulating the ion trapping parameters to maximize the overlap between the ion cloud and the irradiation volume.
Achieving High Efficiency and Eliminating Degradation in Solid Oxide Electrochemical Cells Using High Oxygen‐Capacity Perovskite
Authors: Jun Areum , Kim Junyoung , Shin Jeeyoung , Kim Guntae
Published: September 2016

Recently, there have been efforts to use clean and renewable energy because of finite fossil fuels and environmental problems. Owing to the site‐specific and weather‐dependent characteristics of the renewable energy supply, solid oxide electrolysis cells (SOECs) have received considerable attention to store energy as hydrogen. Conventional SOECs use Ni‐YSZ (yttria‐stabilized zirconia) and LSM (strontium‐doped lanthanum manganites)‐YSZ as electrodes. These electrodes, however, suffer from redox‐instability and coarsening of the Ni electrode along with delamination of the LSM electrode during steam electrolysis. In this study, we successfully design and fabricate highly efficient SOECs using layered perovskites, PrBaMn2O5+δ (PBM) and PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF50), as both electrodes for the first time. The SOEC with layered perovskites as both‐side electrodes shows outstanding performance, reversible cycling, and remarkable stability over 600 hours.
Hierarchical Nanowires Synthesized by Supramolecular Stepwise Polymerization
Authors: Zhuang Zeliang , Jiang Tao , Lin Jiaping , Gao Liang , Yang Chaoying , Wang Liquan , Cai Chunhua
Published: September 2016

The self‐organization of pre‐assembled aggregates is an efficient stepwise strategy for fabricating nanostructures with a second level of hierarchy. Herein, we report that anisotropic spindle‐like micelles, self‐assembled from polypeptide graft copolymers with rigid backbones, can serve as ideal pre‐assembled subunits for constructing one‐dimensional materials with hierarchical structures. By adding organic solvents and dialyzing against water, reactive points can be generated at the ends of the spindle‐like micelles, which subsequently drive the anisotropic micelles to grow as rods in a chain and eventually self‐assemble into hierarchical nanowires in a stepwise manner. The second self‐assembly step is a hierarchical process that resembles step polymerization. Hierarchical structures can be precisely synthesized by this new type of polymerization. These nanostructures can be tailored by the activity of the reactive points, which depends on the nature of the solvent and the molecular architecture.
Surface Modification of Water Purification Membranes
Authors: Miller Daniel J. , Dreyer Daniel R. , Bielawski Christopher W. , Paul Donald R. , Freeman Benny D.
Published: September 2016

Polymeric membranes are an energy‐efficient means of purifying water, but they suffer from fouling during filtration. Modification of the membrane surface is one route to mitigating membrane fouling, as it helps to maintain high levels of water productivity. Here, a series of common techniques for modification of the membrane surface are reviewed, including surface coating, grafting, and various treatment techniques such as chemical treatment, UV irradiation, and plasma treatment. Historical background on membrane development and surface modification is also provided. Finally, polydopamine, an emerging material that can be easily deposited onto a wide variety of substrates, is discussed within the context of membrane modification. A brief summary of the chemistry of polydopamine, particularly as it may pertain to membrane development, is also described.
Symbiotic Control in Mechanical Bond Formation
Authors: Wang Yuping , Sun Junling , Liu Zhichang , Nassar Majed S. , Botros Youssry Y. , Stoddart J. Fraser
Published: September 2016

Since the advent of mechanically interlocked molecules (MIMs), many approaches to templating their formation using various different noncovalent bonding interactions have been introduced and explored. In particular, employing radical‐pairing interactions between BIPY.+ units, the radical cationic state of 4,4′‐bipyridinium (BIPY2+) units, in syntheses is not only a convenient but also an attractive source of templation because of the unique properties residing in the resulting catenanes and rotaxanes. Herein, we report a copper‐mediated procedure that enables the generation, in the MIM‐precursors, of BIPY.+ radical cations, while the metal itself, which is oxidized to CuI, catalyzes the azide–alkyne cycloaddition reactions that result in the efficient syntheses of two catenanes and one rotaxane, assisted by radical‐pairing interactions between the BIPY.+ radical cations. This procedure not only provides a fillip for making and investigating the properties of Coulombically challenged catenanes and rotaxanes, but it also opens up the possibility of synthesizing artificial molecular machines which operate away from equilibrium.
Gold‐Nanoparticle‐Loaded Carbonate‐Modified Titanium(IV) Oxide Surface: Visible‐Light‐Driven Formation of Hydrogen Peroxide from Oxygen
Authors: Teranishi Miwako , Hoshino Riyoko , Naya Shin‐ichi , Tada Hiroaki
Published: September 2016

Gold nanoparticle‐loaded rutile TiO2 with a bimodal size distribution around 10.6 nm and 2.3 nm (BM‐Au/TiO2) was prepared by the deposition precipitation and chemical reduction (DP‐CR) technique. Visible‐light irradiation (λ>430 nm) of the BM‐Au/TiO2 plasmonic photocatalyst yields 35 μm H2O2 in aerated pure water at irradiation time (tp)=1 h, and the H2O2 concentration increases to 640±60 μm by the addition of 4 % HCOOH as a sacrificing electron donor. Further, a carbonate‐modified surface BM‐Au/TiO2 (BM‐Au/TiO2‐CO32−) generates a millimolar level of H2O2 at tp=1 h with a quantum efficiency (Φ) of 5.4 % at λ=530 nm under the same conditions. The recycle experiments confirmed the stable performance of BM‐Au/TiO2.
Economics of biofuels and bioproducts from an integrated pyrolysis biorefinery
Authors: Dang Qi , Hu Wenhao , Rover Marjorie , Brown Robert C. , Wright Mark M.
Published: September 2016

This paper describes a novel integrated biorefinery based on fast pyrolysis and subsequent bio‐oil upgrading to produce three product portfolios: hydrocarbon biofuels (gasoline and diesel), bio‐based products (bioasphalt, calcium acetate, and dextrose), and hydrocarbon chemicals (aromatics, olefins, and fuel oil). Based on the economic assumptions and historical market prices of the products, we calculate internal rates of return (IRRs) of the biorefinery (2000 dry metric tons per day) over 30 years to evaluate its performance. Given the historical low, average, and high prices of the products, a total of 27 scenarios are explored and the maximum IRR for each scenario is determined. Results indicate that upgrading bio‐oil to bio‐based products yields the maximum IRR of 67.9% if bio‐based products can be marketed at a historical high price level (between $257 and $1491 per metric ton) and an IRR of 42.5% at an average price level (between $240 and $950 per metric ton). Under some market conditions, the biorefinery should produce hydrocarbon chemicals or biofuels to increase the IRR. We also estimate the IRR probability distribution using Monte Carlo simulation by ‐incorporating distributions of product prices and bio‐oil fractions allocated for three product portfolios. Average IRRs of −3.9% for biofuels, 42.7% for bio‐based products, and 17.3% for hydrocarbon chemicals are observed with standard deviations of 24.4%, 24.1%, and 6.5%, respectively. The integrated ‐biorefinery exhibits an IRR distribution of 16.2% ± 16.4% suggesting that the integrated biorefinery could balance the economic disadvantages and benefits from individual product portfolio to achieve profitable IRRs. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
Untersuchungen zu Herstellungs‐ und Instandhaltungs kosten von unterschiedlichen Konzepten zur Sicherstellung der Dauerhaftigkeit von Parkbauten
Authors: Schubert Maren , Dauberschmidt Christoph , Eltschig Christian , Nechvatal Dirk , Rapolder Markus , Schedl Tobias
Published: September 2016

Es ist derzeit eine intensive Diskussion im Gange, wie man die Dauerhaftigkeit von Parkbauten sicherstellen kann. Dabei werden häufig Kosten als Argument für oder gegen eine bestimmte Ausführung vorgebracht, ohne dass bisher eine durchgängige Kostenbetrachtung für verschiedene Konzepte zur Sicherstellung der Dauerhaftigkeit durchgeführt worden ist.

In dieser Veröffentlichung werden die Kosten verschiedener Konzepte anhand einer virtuellen zweigeschossigen Tiefgarage mit üblichen Abmessungen für die beiden maßgeblichen Bauteile „Zwischendecke” und „Bodenplatte” verglichen. Dabei wird bei den Herstellungskosten z. B. auch die von dem Oberflächenschutz‐ oder Abdichtungssystem abhängige Mindestbewehrung berücksichtigt. Zudem werden in Abhängigkeit vom gewählten Oberflächenschutz‐ oder Abdichtungssystem die Kosten für die Instandhaltung, bestehend u. a. aus der Wartung, der Inspektion und der Instandsetzung, über einen Nutzungszeitraum von 50 Jahren angesetzt und miteinander ver glichen. Bei den Kostenansätzen werden die marktüblichen Schwankungen bzw. die angesetzten Instandsetzungszyklen durch die Betrachtung von Mittel‐, Minimal‐ und Maximalwerten berücksichtigt.

Für die Zwischendecke werden die Beschichtungs‐ bzw. Abdichtungssysteme „OS 11”, „Gussasphalt (ein‐/zweischichtig) mit Schweißbahn”, „Gussasphalt (ein‐/zweischichtig) mit OS 10” und „PMMA” betrachtet. Für die Bodenplatte werden getrennt für die Lastfälle „Wasserwechselzone” (WW) und „Wasserdruck” (WD) die Systeme „OS 11”, „Gussasphalt (ein‐/zweischichtig) mit Schweißbahn” und „OS 8 mit begleitender Rissbehandlung” untersucht. Dabei werden für die laufenden Instandhaltungskosten ingenieurmäßige Anhaltswerte nach dem jetzigen Wissensstand gewählt. Es wird erwartet, dass durch aktuell laufende Forschungsprojekte zukünftig wissenschaftlich fundierte Ansätze vorliegen werden, die zu einer Fortschreibung des Kostenvergleichs führen werden.
Zentrische Druckversuche an schlanken UHPC‐Stützen
Authors: Schmidt Angela , Curbach Manfred
Published: September 2016

Im Rahmen des von der DFG geförderten Schwerpunktprogramms (SPP) 1542 „Leicht Bauen mit Beton” wurden im Teilprojekt „Querschnittsadaption stabförmiger Druckbauteile” zentrische Druckversuche an unbewehrten UHPC‐Stützen mit quadratischem und rechteckigem Querschnitt durchgeführt. Die Ergebnisse wurden anschließend mit Versuchsreihen anderer Forscher verglichen. Der Fokus der Untersuchungen lag auf dem Versagensverhalten von knickgefährdeten Stützen bei unterschiedlichen Randbedingungen. Für diese Versuche wurden sowohl eine gelenkige als auch eine eingespannte Lagerung umgesetzt. Neben einer Analyse des Versagensvorgangs wurden die Ergebnisse mit der idealen Knicklast nach Euler und mit der Spannungsgleichung nach Theorie II. Ordnung verglichen. Vor‐ und Nachteile der Ansätze werden abschließend aufgezeigt, gegenübergestellt und diskutiert.
Transposable elements: Self‐seekers of the germline, team‐players of the soma
Authors: Haig David
Published: September 2016

The germ track is the cellular path by which genes are transmitted to future generations whereas somatic cells die with their body and do not leave direct descendants. Transposable elements (TEs) evolve to be silent in somatic cells but active in the germ track. Thus, the performance of most bodily functions by a sequestered soma reduces organismal costs of TEs. Flexible forms of gene regulation are permissible in the soma because of the self‐imposed silence of TEs, but strict licensing of transcription and translation is maintained in the germ track to control proliferation of TEs. Delayed zygotic genome activation (ZGA) and maternally inherited germ granules are adaptations that enhance germ‐track security. Mammalian embryos exhibit very early ZGA associated with extensive mobilization of retroelements. This window of vulnerability to retrotransposition in early embryos is an indirect consequence of evolutionary conflicts within the mammalian genome over postzygotic maternal provisioning.
Discovery of Unusual Biaryl Polyketides by Activation of a SilentStreptomyces venezuelaeBiosynthetic Gene Cluster
Authors: Thanapipatsiri Anyarat , Gomez‐Escribano Juan Pablo , Song Lijiang , Bibb Maureen J. , Al‐Bassam Mahmoud , Chandra Govind , Thamchaipenet Arinthip , Challis Gregory L. , Bibb Mervyn J.
Published: September 2016

Comparative transcriptional profiling of a ΔbldMmutant ofStreptomyces venezuelaewith its unmodified progenitor revealed that the expression of a cryptic biosynthetic gene cluster containing both type I and type III polyketide synthase genes is activated in the mutant. The 29.5 kb gene cluster, which was predicted to encode an unusual biaryl metabolite, which we named venemycin, and potentially halogenated derivatives, contains 16 genes including one—vemR—that encodes a transcriptional activator of the large ATP‐binding LuxR‐like (LAL) family. Constitutive expression ofvemRin the ΔbldMmutant led to the production of sufficient venemycin for structural characterisation, confirming its unusual biaryl structure. Co‐expression of the venemycin biosynthetic gene cluster andvemRin the heterologous hostStreptomyces coelicoloralso resulted in venemycin production. Although the gene cluster encodes two halogenases and a flavin reductase, constitutive expression of all three genes led to the accumulation only of a monohalogenated venemycin derivative, both in the native producer and the heterologous host. A competition experiment in which equimolar quantities of sodium chloride and sodium bromide were fed to the venemycin‐producing strains resulted in the preferential incorporation of bromine, thus suggesting that bromide is the preferred substrate for one or both halogenases.
Intrapancreatic accessory spleen: a rare cause of recurrence of immune thrombocytopenic purpura
Authors: García Angarita Francisco , Sanjuanbenito Dehesa Alfonso
Published: September 2016

Key Clinical Message

Accessory splenectomy should be considered in any patient with recurrence of immune thrombocytopenic purpura, if studies (scintigraphy using heat‐damaged Tc99m‐labeled red blood cells) are suggestive of residual functional splenic tissue. The most common benefit after removal of accessory spleen seems to be the reduction of dose in medical treatment.
Highly Selective and Stable NiSn/SiO2 Catalyst for Isobutane Dehydrogenation: Effects of Sn Addition
Authors: Wang Guowei , Wang Haoren , Zhang Huanling , Zhu Qingqing , Li Chunyi , Shan Honghong
Published: September 2016

Ni/SiO2 catalysts with large surface area Ni particles exhibit high hydrogenolysis activity, leading to the formation of large amounts of methane and coke. To destroy the active sites for hydrogenolysis, namely the aggregated Ni ensembles, Sn species were introduced into the Ni/SiO2 catalyst. As expected, isobutene selectivity was significantly increased to 90.2 %. The promoting role of Sn on the dehydrogenation performance could be interpreted as both a geometric and electronic effect. On one hand, Sn addition efficiently dispersed aggregated Ni particles and reduced Ni particle size from 77 to 16 nm, weakening the ability of Ni for C−C bond rupture. On the other hand, additional electrons provided by Sn led to a high electronic density of Ni, facilitating the desorption of isobutene from the catalyst and suppressing secondary reactions. Consequently, coke formation was effectively inhibited over the NiSn/SiO2 catalyst, further guaranteeing a good stability and prolonged cycle time.
On the Synergism between Cu and Ni for Photocatalytic Hydrogen Production and their Potential as Substitutes of Noble Metals
Authors: Majeed Imran , Nadeem Muhammad Amtiaz , Hussain Ejaz , Waterhouse Geoffrey I. N. , Badshah Amin , Iqbal Azhar , Nadeem Muhammad Arif , Idriss Hicham
Published: September 2016

A series of Cu(OH)2–Ni(OH)2/P25 photocatalysts was prepared by co‐deposition–precipitation (total metal loading ≈1 wt %) and their performance was evaluated for H2 production. Among this series, the 0.8 Cu(OH)2–0.2 Ni(OH)2/P25 photocatalyst demonstrated very high H2 production rates in 20 vol % ethanol/water and 5 vol % glycerol/water mixtures (10 and 22 mmol h−1 g−1, respectively). Detailed analyses based on reaction kinetics, photoluminescence, X‐ray photoelectron spectroscopy (XPS), and charge carrier scavenging suggest that both working catalysts are composed of Cu and Ni metals in their active phases. Cu0 is produced directly by the transfer of electrons from the conduction band of TiO2 to surface Cu(OH)2 nanoclusters, whereas Ni0 is formed indirectly through a process of gradual dissolution of Ni(OH)2 to yield aqueous Ni2+ owing to the acidic environment of the medium, followed by Ni2+ reduction by electrons from the TiO2 conduction band. The high rates of H2 production that match those obtained with noble metals can be explained owing to a considerably less negative ΔGo of Cu oxide formation when compared with that of Ni oxide formation and higher work function of Ni than that of Cu.
Reverse Stereoselectivity in the Lipase‐Catalyzed Hydrolysis of Diacetylated Pyrimidine Acyclonucleosides
Authors: Kołodziejska Renata , Studzińska Renata
Published: September 2016

The enzymatic hydrolysis of the prochiral acetyl groups of pyrimidine acyclonucleoside derivatives was catalyzed effectively by lipase Amano PS from Burkholderia cepacia (BCL) to give monoacetates with a high optical purity. The stereopreference of BCL depends on the structure of the substrates. The BCL‐catalyzed hydrolysis of the unsubstituted acyclonucleoside 2‐{[2,4‐dioxo‐3,4,5,6,7,8‐hexahydroquinazolin‐1(2H)‐yl]methoxy}propane‐1,3‐diyl diacetate is enantiotopically selective (pro‐R). After the reaction, the enantiomerically pure 2‐S isomer was obtained. The additional group on the ring caused a dramatic change in the stereopreference of the enzyme‐catalyzed deacylation compared to that of the unsubstituted compound, and the reverse chiral preference was observed. The enzymatic deacylation of prochiral ester groups of acyclonucleoside analogs substituted at C‐6 and C‐8 in 2,4‐dioxo‐3,4,5,6,7,8‐hexahydroquinazoline ring led to the 2‐R isomer (pro‐S selectivity).
Activating Oxygen Molecules over Carbonyl‐Modified Graphitic Carbon Nitride: Merging Supramolecular Oxidation with Photocatalysis in a Metal‐Free Catalyst for Oxidative Coupling of Amines into Imines
Authors: Zhang Jun‐Jun , Ge Jie‐Min , Wang Hong‐Hui , Wei Xiao , Li Xin‐Hao , Chen Jie‐Sheng
Published: September 2016

Carbonyl‐modified carbon nitride (m‐O=C3N4) can act as a highly efficient metal‐free photocatalyst for selective oxidation reactions, as exemplified herein by the oxidative coupling of amines to imines by using dioxygen molecules and visible light. The C=O groups built‐in on the surface of the material significantly boosted the activity by following the principle of supramolecular oxidation, that is, they largely promoted the oxidation reaction at room temperature by binding in situ formed H2O2 photogenerated on the surface from the dioxygen molecules and accelerated the reaction between H2O2 and the amines.
Role of Organic Acids in Flux Enhancement of Polyamide Nanofiltration Membranes
Authors: Akbari Ahmad , Ostadmoradi Nafiseh , Rostami Sayed Majid Mojallali , Homayoonfal Maryam
Published: September 2016

A novel thin‐film composite (TFC) nanofiltration membrane containing hydrophilic organic additives was fabricated via interfacial polymerization. Three organic acids, i.e., lactic, maleic, and citric acid, served as aqueous‐phase additives and their role in membrane structure and nanofiltration membrane flux enhancement was investigated. Fourier transform‐infrared (FT‐IR) analysis confirmed the presence of organic acids in the polyamide (PA) layer. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses were applied to investigate the membrane morphology. The more carboxylic functional groups present in the additive resulted in higher hydrophilicity and porosity and flux was enhanced significantly compared to the neat PA membrane, while salt rejection was influenced only to a minor extent.
Highly Dispersed Polyoxometalate‐Doped Porous Co3O4 Water Oxidation Photocatalysts Derived from POM@MOF Crystalline Materials
Authors: Lan Qing , Zhang Zhi‐Ming , Qin Chao , Wang Xin‐Long , Li Yang‐Guang , Tan Hua‐Qiao , Wang En‐Bo
Published: September 2016

Rational design of earth‐abundant photocatalysts is an important issue for solar energy conversion and storage. Polyoxometalate (POM)@Co3O4 composites doped with highly dispersive molecular metal–oxo clusters, synthesized by loading a single Keggin‐type POM cluster into each confined space of a metal–organic framework (MOF), exhibit significantly improved photocatalytic activity in water oxidation compared to the pure MOF‐derived nanostructure. The systematic synthesis of these composite nanocrystals allows the conditions to be tuned, and their respective water oxidation catalytic performance can be efficiently adjusted by varying the thermal treatment temperature and the feeding amount of the POM. This work not only provides a modular and tunable synthetic strategy for preparing molecular cluster@TM oxide (TM=transition metal) nanostructures, but also showcases a universal strategy that is applicable to design and construct multifunctional nanoporous metal oxide composite materials.
Stepwise Regioselective Hydrogenation of cis‐2‐C60(CF2)2 Homofullerene with [6,6]‐Open/Closed Valence Tautomerism
Authors: Bogdanov Viktor P. , Semivrazhskaya Olesya O. , Belov Nikita M. , Troyanov Sergey I. , Markov Vitaliy Yu. , Ioffe Ilya N. , Kemnitz Erhard , Goryunkov Alexey A.
Published: September 2016

The homofullerene compound cis‐2‐C60(CF2)2, which has an unusual kind of open/closed valence tautomerism undergoes consecutive regioselective hydrogenation at bridgehead carbon atoms upon reduction with Zn/Cu couple in H2O‐toluene mixture. The tautomerism barrier in cis‐2‐C60(CF2)2 is negligible in the neutral state, whereas negative charging both impedes tautomeric transformation and promotes regioselective addition of electrophilic species at the bridgehead carbon atoms. In light of this observation, two novel homofullerene derivatives, mixed [6,6]‐open/closed C60(CF2)2H2 and [6,6]‐open cis‐2‐C60(CF2)2H4, were synthesized and their structures were unambiguously determined by means of single crystal X‐ray crystallography and NMR spectroscopy.
Phosphorus and Halogen Co‐Doped Graphene Materials and their Electrochemistry
Authors: Wang Lu , Sofer Zdenek , Zboril Radek , Cepe Klara , Pumera Martin
Published: September 2016

Doping of graphene materials with heteroatoms is important as it can change their electronic and electrochemical properties. Here, graphene is co‐doped with n‐type dopants such as phosphorus and halogen (Cl, Br, I). Phosphorus and halogen are introduced through the treatment of graphene oxide with PX3 gas (PCl3, PBr3, and PI3). Graphene oxides are prepared through chlorate and permanganate routes. Detailed chemical and structural characterization demonstrates that the graphene sheets are covered homogeneously by phosphorus and halogen atoms. It is found that the amount of phosphorus and halogen introduced depends on the graphene oxide preparation method. The electrocatalytic effect of the resulting co‐doped materials is demonstrated for industrially relevant electrochemical reactions such as the hydrogen evolution and oxygen reduction reactions.
Detoxification of Chemical Warfare Agents Using a Zr6‐Based Metal–Organic Framework/Polymer Mixture
Authors: Moon Su‐Young , Proussaloglou Emmanuel , Peterson Gregory W. , DeCoste Jared B. , Hall Morgan G. , Howarth Ashlee J. , Hupp Joseph T. , Farha Omar K.
Published: September 2016

Owing to their high surface area, periodic distribution of metal sites, and water stability, zirconium‐based metal–organic frameworks (Zr6‐MOFs) have shown promising activity for the hydrolysis of nerve agents GD and VX, as well as the simulant, dimethyl 4‐nitrophenylphosphate (DMNP), in buffered solutions. A hurdle to using MOFs for this application is the current need for a buffer solution. Here the destruction of the simulant DMNP, as well as the chemical warfare agents (GD and VX) through hydrolysis using a MOF catalyst mixed with a non‐volatile, water‐insoluble, heterogeneous buffer is reported. The hydrolysis of the simulant and nerve agents in the presence of the heterogeneous buffer was fast and effective.
ChemInform Abstract: Chemical Sensors Based on Metal—Organic Frameworks
Authors: Yi Fei‐Yan , Chen Dongxiao , Wu Meng‐Ke , Han Lei , Jiang Hai‐Long
Published: September 2016

Review: [34 refs.
In‐situ‐Reaktionsverfolgung mittels ATR‐IR‐Spektroskopie bei der CO2‐Hydrierung zu Ameisensäure
Authors: Ehnes Christoph , Lucas Martin , Claus Peter
Published: September 2016

Bei der Hydrierung von Kohlendioxid zu Ameisensäure stellt die Analytik aufgrund der ungünstigen Gleichgewichtslage und des komplexen Reaktionsmediums eine Herausforderung dar. Geringe Ausbeuten, trotz des Einsatzes eines Ru/γ‐Al2O3‐Katalysators, Bildung von Ameisensäure‐Amin‐Addukten und Folgereaktionen mit dem Lösungsmittel erschweren die Analytik. Die Kopplung des Reaktors mit der ATR‐IR‐Spektroskopie gestattet die präzise In‐situ‐Verfolgung der Reaktion. Eine weitere Stärke ist die störungsfreie Zugänglichkeit der initialen Kinetik. So konnte eine Abweichung vom Arrheniusverhalten gefunden werden.
Ethylene Epoxidation with Nitrous Oxide over Fe–BTC Metal–Organic Frameworks: A DFT Study
Authors: Maihom Thana , Choomwattana Saowapak , Wannakao Sippakorn , Probst Michael , Limtrakul Jumras
Published: September 2016

The epoxidation of ethylene with N2O over the metal‐organic framework Fe–BTC (BTC=1,3,5‐benzentricarboxylate) is investigated by means of density functional calculations. Two reaction paths for the production of ethylene oxide or acetaldehyde are systematically considered in order to assess the efficiency of Fe–BTC for the selective formation of ethylene oxide. The reaction starts with the decomposition of N2O to form an active surface oxygen atom on the Fe site of Fe–BTC, which subsequently reacts with an ethylene molecule to form an ethyleneoxy intermediate. This intermediate can then be selectively transformed either by 1,2‐hydride shift into the undesired product acetaldehyde or into the desired product ethylene oxide by way of ring closure of the intermediate. The production of ethylene oxide requires an activation energy of 5.1 kcal mol−1, which is only about one‐third of the activation energy of acetaldehyde formation (14.3 kcal mol−1). The predicted reaction rate constants for the formation of ethylene oxide in the relevant temperature range are approximately 2–4 orders of magnitude higher than those for acetaldehyde. Altogether, the results suggest that Fe–BTC is a good candidate catalyst for the epoxidation of ethylene by molecular N2O.