bluuebunny/crossref_metadata_2025 huggingface dataset:
Deriving Global OH Abundance and Atmospheric Lifetimes for Long‐Lived Gases: A Search for CH3CCl3 Alternatives
Authors: Liang Qing , Chipperfield Martyn P. , Fleming Eric L. , Abraham N. Luke , Braesicke Peter , Burkholder James B. , Daniel John S. , Dhomse Sandip , Fraser Paul J. , Hardiman Steven C. , Jackman Charles H. , Kinnison Douglas E. , Krummel Paul B. , Montzka Stephen A. , Morgenstern Olaf , McCulloch Archie , Mühle Jens , Newman Paul A. , Orkin Vladimir L. , Pitari Giovanni , Prinn Ronald G. , Rigby Matthew , Rozanov Eugene , Stenke Andrea , Tummon Fiona , Velders Guus J. M. , Visioni Daniele , Weiss Ray F.
Published: October 2017

An accurate estimate of global hydroxyl radical (OH) abundance is important for projections of air quality, climate, and stratospheric ozone recovery. As the atmospheric mixing ratios of methyl chloroform (CH3CCl3) (MCF), the commonly used OH reference gas, approaches zero, it is important to find alternative approaches to infer atmospheric OH abundance and variability. The lack of global bottom‐up emission inventories is the primary obstacle in choosing a MCF alternative. We illustrate that global emissions of long‐lived trace gases can be inferred from their observed mixing ratio differences between the Northern Hemisphere (NH) and Southern Hemisphere (SH), given realistic estimates of their NH‐SH exchange time, the emission partitioning between the two hemispheres, and the NH versus SH OH abundance ratio. Using the observed long‐term trend and emissions derived from the measured hemispheric gradient, the combination of HFC‐32 (CH2F2), HFC‐134a (CH2FCF3, HFC‐152a (CH3CHF2), and HCFC‐22 (CHClF2), instead of a single gas, will be useful as a MCF alternative to infer global and hemispheric OH abundance and trace gas lifetimes. The primary assumption on which this multispecies approach relies is that the OH lifetimes can be estimated by scaling the thermal reaction rates of a reference gas at 272 K on global and hemispheric scales. Thus, the derived hemispheric and global OH estimates are forced to reconcile the observed trends and gradient for all four compounds simultaneously. However, currently, observations of these gases from the surface networks do not provide more accurate OH abundance estimate than that from MCF.
Raindrop Size Distribution Measurements at 4,500 m on the Tibetan Plateau During TIPEX‐III
Authors: Chen Baojun , Hu Zhiqun , Liu Liping , Zhang Guifu
Published: October 2017

As part of the third Tibetan Plateau Atmospheric Scientific Experiment field campaign, raindrop size distribution (DSD) measurements were taken with a laser optical disdrometer in Naqu, China, at 4,508 m above sea level (asl) during the summer months of 2013, 2014, and 2015. The characteristics of DSDs for five different rain rates, for two rain types (convective and stratiform), and for daytime and nighttime rains were studied. The shapes of the averaged DSDs were similar for different rain rates, and the width increased with rainfall intensity. Little difference was found in stratiform DSDs between day and night, whereas convective DSDs exhibited a significant day‐night difference. Daytime convective DSDs had larger mass‐weighted mean diameters (Dm) and smaller generalized intercepts (NW) than the nighttime DSDs. The constrained relations between the intercept N0 and shape μ, slope Λ and μ, and NW and Dm of gamma DSDs were derived. We also derived empirical relations between Dm and the radar reflectivity factor in the Ku and Ka bands.
Rapid Adjustments Cause Weak Surface Temperature Response to Increased Black Carbon Concentrations
Authors: Stjern Camilla Weum , Samset Bjørn Hallvard , Myhre Gunnar , Forster Piers M. , Hodnebrog Øivind , Andrews Timothy , Boucher Olivier , Faluvegi Gregory , Iversen Trond , Kasoar Matthew , Kharin Viatcheslav , Kirkevåg Alf , Lamarque Jean‐François , Olivié Dirk , Richardson Thomas , Shawki Dilshad , Shindell Drew , Smith Christopher J. , Takemura Toshihiko , Voulgarakis Apostolos
Published: October 2017

We investigate the climate response to increased concentrations of black carbon (BC), as part of the Precipitation Driver Response Model Intercomparison Project (PDRMIP). A tenfold increase in BC is simulated by nine global coupled‐climate models, producing a model median effective radiative forcing of 0.82 (ranging from 0.41 to 2.91) W m−2, and a warming of 0.67 (0.16 to 1.66) K globally and 1.24 (0.26 to 4.31) K in the Arctic. A strong positive instantaneous radiative forcing (median of 2.10 W m−2 based on five of the models) is countered by negative rapid adjustments (−0.64 W m−2 for the same five models), which dampen the total surface temperature signal. Unlike other drivers of climate change, the response of temperature and cloud profiles to the BC forcing is dominated by rapid adjustments. Low‐level cloud amounts increase for all models, while higher‐level clouds are diminished. The rapid temperature response is particularly strong above 400 hPa, where increased atmospheric stabilization and reduced cloud cover contrast the response pattern of the other drivers. In conclusion, we find that this substantial increase in BC concentrations does have considerable impacts on important aspects of the climate system. However, some of these effects tend to offset one another, leaving a relatively small median global warming of 0.47 K per W m−2—about 20% lower than the response to a doubling of CO2. Translating the tenfold increase in BC to the present‐day impact of anthropogenic BC (given the emissions used in this work) would leave a warming of merely 0.07 K.
Can We Monitor Snow Properties on Sea Ice to Investigate Its Role in Tropospheric Ozone Depletion?
Authors: Domine Florent
Published: October 2017

In the lower troposphere over the Arctic Ocean, ozone is often destroyed in spring by chemical chain reactions involving the reactive bromine species Br and BrO. The role of surface snow in generating reactive bromine has been suspected, but many details of the processes not understood. Using unique data such as BrO concentrations from instruments on buoys, Burd et al. (2017, https://doi.org/10.1002/2017JD026906) observed that the snowmelt onset date often coincides with the end of the reactive bromine season. They proposed that the decrease in snow‐specific surface area and/or the occurrence of liquid water in snow induced by melting dramatically slows the rate of surface reactions generating bromine, indicating that the physical state of the snow is critical for bromine generation. Their suggestion is discussed, and a method to test it using novel instrumentation recently available is proposed.
The Total Electron Content of the Martian Ionosphere From MRO/SHARAD Observations
Authors: Mendillo Michael , Narvaez Clara , Campbell Bruce
Published: October 2017

The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter (MRO), used to search for subsurface water ice, requires corrections to range delays and image distortions caused by radiowave propagation through the Martian ionosphere. These corrections yield a phase parameter that is linearly correlated with values of the total electron content (TEC), defined as the integral of the electron density profile Ne(h). This new database has been validated using previous observational patterns of TEC magnitudes and variability versus latitude, local time, and season. The SHARAD TEC data span the years 2007 to 2014, providing the first opportunity to study solar cycle effects upon daytime TEC magnitudes. A parameterization of TEC versus solar zenith angle and solar flux, within the context of photochemical equilibrium theory, provides a flexible TEC module for the Mars Initial Reference Ionosphere (MIRI) model. A high spatial resolution study of TEC variability in the southern hemisphere confirmed a previously tentative conclusion about daytime TEC morphology controlled by the local inclination angles of crustal magnetic fields.
Silicate Weathering and Carbon Cycle Controls on the Oligocene‐Miocene Transition Glaciation
Authors: Stewart Joseph A. , James Rachael H. , Anand Pallavi , Wilson Paul A.
Published: October 2017

Changes in both silicate weathering rates and organic carbon burial have been proposed as drivers of the transient “Mi‐1” glaciation event at the Oligocene‐Miocene transition (OMT; ~23 Ma). However, detailed geochemical proxy data are required to test these hypotheses. Here we present records of Li/Ca, Mg/Ca, Cd/Ca, U/Ca, δ18O, δ13C, and shell weight in planktonic foraminifera from marine sediments spanning the OMT in the equatorial Atlantic Ocean. Li/Ca values increase by 1 μmol/mol across this interval. We interpret this to indicate an ~20% increase in silicate weathering rates, which would have lowered atmospheric CO2, potentially forcing the Antarctic glaciation ~ 23 Ma. δ13C of thermocline dwelling planktonic foraminifera track the global increase in seawater δ13C across the OMT and during the Mi‐1 event, hence supporting a hypothesized global increase in organic carbon burial rates. High δ13C previously measured in epipelagic planktonic foraminifera and high Cd/Ca ratios during Mi‐1 are interpreted to represent locally enhanced primary productivity, stimulated by increased nutrients supply to surface waters. The fingerprint of high export production and associated organic carbon burial at this site is found in reduced bottom water oxygenation (inferred from high foraminiferal U/Ca) and enhanced respiratory dissolution of carbonates, characterized by reduced foraminiferal shell weight. Replication of our results elsewhere would strengthen the case that weathering‐induced CO2 sequestration preconditioned climate for Antarctic ice sheet growth across the OMT, and increased burial of organic carbon acted as a feedback that intensified cooling at this time.
Possible Cause of Extremely Bright Aurora Witnessed in East Asia on 17 September 1770
Authors: Ebihara Yusuke , Hayakawa Hisashi , Iwahashi Kiyomi , Tamazawa Harufumi , Kawamura Akito Davis , Isobe Hiroaki
Published: October 2017

Extremely bright aurora was witnessed in East Asia on 17 September 1770, according to historical documents. The aurora was described as “as bright as a night with full moon” at magnetic latitude of 25°. The aurora was dominated by red color extending from near the horizon up beyond the polar star (corresponding to elevation angle of ~35°). We performed a two‐stream electron transport code to calculate the volume emission rates at 557.7 nm (OI) and 630.0 nm (OI). Two types of distribution of precipitating electrons were assumed. The first one is based on the unusually intense electron flux measured by the DMSP satellite in the March 1989 storm. The distribution consists of hot (peaking at 3 keV) and cold (peaking at 71 eV) components. The second one is the same as the first one, but the hot component is removed. We call this high‐intensity low‐energy electrons (HILEEs). The first spectrum results in an auroral display with a bright, lower green border. The second one results in red‐dominated aurora extending up to the elevation angle of 35° when the equatorward boundary of the electron precipitation is located at 32° invariant latitude. The poleward boundary of the precipitation would be 42° invariant latitude or greater to explain the auroral display extending from near the horizon. The origin of the HILEEs is probably the plasma sheet or the plasmasphere that is transported earthward toL ~ 1.39 due to enhanced magnetospheric convection. Local heating or acceleration is also plausible.
Social Desirability and the Interpretation of Uncertainty Terms in Self‐Report Questions
Authors: Holtgraves Thomas
Published: October 2017

Uncertainty terms (e.g., possible) are words that are not fixed and hence open to interpretation. This research examined the role of social desirability in how these words are interpreted in self‐report questions. Participants in Experiments 1 (N = 96; MTurk workers) and 2 (N = 96; college students) judged trait (N = 48) and behavior (N = 36) items endorsed by a hypothetical individual to be more likely if they were lower in social desirability. In Experiments 3 (N = 97) and 4 (N = 97) college student participants interpreted four different uncertainty terms (likely, possible, unlikely, and pretty sure) as indicating greater certainty when they referred to socially undesirable (relative to socially desirable) traits (N = 36) and behaviors (N = 24). These results suggest that participants may interpret self‐report items differently, depending on the social desirability of the content.Copyright © 2017 John Wiley & Sons, Ltd.
A fuzzy C‐regression model algorithm using a new PSO algorithm
Authors: Taieb Adel , Soltani Moez , Chaari Abdelkader
Published: October 2017

In this paper, a new methodology is introduced for the identification of the parameters of the multiple‐input–multiple‐output local linear Takagi‐Sugeno fuzzy models using the weighted recursive least squares (WRLS). The WRLS is sensitive to initialization, which leads to no convergence. In order to overcome this problem, adaptive chaos particle swarm optimization is proposed to optimize the initial states of WRLS. This new algorithm is improved versions of the original particle swarm optimization algorithm. Finally, comparative experiments are designed to verify the validity of the proposed clustering algorithm and the Takagi‐Sugeno fuzzy model identification method, and the results show that the new method is effective in describing a complicated nonlinear system with significantly high accuracies compared with approaches in the literature.
Influences of Friction Stir Welding and Post‐Weld Heat Treatment on Al–Cu–Li Alloy
Authors: Lin Yi , Lu Change , Wei Chengyang , Zheng Ziqiao
Published: October 2017

In this paper, the influences of friction stir welding (FSW) and post‐weld heat treatment (PWHT) on the microstructures and tensile properties of Al–Cu–Li alloy are investigated. After FSW, strengthen loss occurred in the welding area. Remarkable softening occurs in the thermo‐mechanically affected zone (TMAZ) resulting from dissolution of Al3Li (δ′) phases. Recrystallization and precipitation of ultra‐fine δ′ phases take place in the nugget zone (NZ) that lightens the softening degree of this zone. A noteworthy enhancement in the hardness and tensile strength of the joint is achieved after T8 re­aging treatment (3% − pre‐deformation, 30 h at 152 °C). However, re‐solution treatment coupled with re‐aging treatment leads to ductility deterioration in the joint because coplanar slip of coarse Al3Li phases induces severe stress concentration during plastic deformation.
Spectroscopic Indications of Tunnel Barrier Charging as the Switching Mechanism in Memristive Devices
Authors: Arndt Benedikt , Borgatti Francesco , Offi Francesco , Phillips Monifa , Parreira Pedro , Meiners Thorsten , Menzel Stephan , Skaja Katharina , Panaccione Giancarlo , MacLaren Donald A. , Waser Rainer , Dittmann Regina
Published: October 2017

Resistive random access memory is a promising, energy‐efficient, low‐power “storage class memory” technology that has the potential to replace both flash storage and on‐chip dynamic memory. While the most widely employed systems exhibit filamentary resistive switching, interface‐type switching systems based on a tunable tunnel barrier are of increasing interest. They suffer less from the variability induced by the stochastic filament formation process and the choice of the tunnel barrier thickness offers the possibility to adapt the memory device current to the given circuit requirements. Heterostructures consisting of a yttria‐stabilized zirconia (YSZ) tunnel barrier and a praseodymium calcium manganite (PCMO) layer are employed. Instead of spatially localized filaments, the resistive switching process occurs underneath the whole electrode. By employing a combination of electrical measurements, in operando hard X‐ray photoelectron spectroscopy and electron energy loss spectroscopy, it is revealed that an exchange of oxygen ions between PCMO and YSZ causes an electrostatic modulation of the effective height of the YSZ tunnel barrier and is thereby the underlying mechanism for resistive switching in these devices.
Thrombosis‐Responsive Thrombolytic Coating Based on Thrombin‐Degradable Tissue Plasminogen Activator (t‐PA) Nanocapsules
Authors: Li Cong , Du Hui , Yang Aizhen , Jiang Shuaibing , Li Zhenhua , Li Dan , Brash John L. , Chen Hong
Published: October 2017

Surface modification with bioactive agents capable of combating thrombosis is a widely used strategy for developing antithrombotic biomaterials. However, exposure of the blood to the antithrombotic agent on the material surface may cause hemostatic disorders under normal conditions. Ideally an implanted biomaterial should respond appropriately on demand to a specific change in the physiologic environment, as happens in the body itself. In the present study, a thrombosis‐responsive surface coating with the ability to lyse fibrin as it forms is reported. The coating consists of nanocapsules (NCs) in which the fibrinolysis activator t‐PA is encapsulated in a thrombin‐degradable hydrogel shell. The t‐PA NCs are attached to several materials covalently through a polydopamine adhesive layer. The resulting surfaces are treated with the antifouling agent glutathione (GSH) to prevent further interactions with blood/plasma components. The t‐PA NCs/GSH‐coated surface is stable and remain inert in normal plasma environment while releasing t‐PA and promoting fibrinolysis when thrombin is present. The fibrinolytic activity increases with increasing thrombin concentration, and therefore presumably with the extent of thrombosis. This work constitutes the first report of an antithrombotic coating whose function is triggered and regulated, respectively, by the appearance of thrombin and the extent of coagulation.
A Multifunctional Nanoplatform against Multidrug Resistant Cancer: Merging the Best of Targeted Chemo/Gene/Photothermal Therapy
Authors: Cheng Wei , Nie Junpeng , Gao Nansha , Liu Gan , Tao Wei , Xiao Xiaojun , Jiang Lijuan , Liu Zhigang , Zeng Xiaowei , Mei Lin
Published: October 2017

Synergistic therapy that combines chemo‐, gene‐, or photothermal means shows great potential for enhancing the therapeutic effects on cancers. Tumor‐targeted nanoparticles based on a doxorubicin (DOX)‐gated mesoporous silica nanocore (MSN) encapsulated with permeability glycoprotein (P‐gp) small interfering RNA (siRNA) and a polydopamine (PDA) outer layer for DOX loading and folic acid decoration are designed. The multifunctional nanoplatform tactfully integrates chemo‐ (DOX), gene‐ (P‐gp siRNA), and photothermal (PDA layer) substances in one system. In vitro results reveal that DOX release behaviors are both pH‐ and thermal‐responsive and the release of co‐delivered P‐gp siRNA is also pH‐dependent due to the pH‐cleavable DOX gatekeeper on MSN. In addition, due to the near‐infrared light‐responsive PDA outer layer and folic acid conjugation, the nanoparticles exhibit outstanding photothermal activity and selective cell targeting ability. Subsequently, in vitro and in vivo antitumor experiments both demonstrate the enhanced antitumor efficacy of the multifunctional nanoparticles, indicating the significance of synergistic therapy combining chemo‐, gene‐, and photothermal treatments in one system.
Suppressing Lithium Dendrite Growth by Metallic Coating on a Separator
Authors: Lee Hongkyung , Ren Xiaodi , Niu Chaojiang , Yu Lu , Engelhard Mark H. , Cho Inseong , Ryou Myung‐Hyun , Jin Hyun Soo , Kim Hee‐Tak , Liu Jun , Xu Wu , Zhang Ji‐Guang
Published: October 2017

Lithium (Li) metal is one of the most promising candidates for the anode in high‐energy‐density batteries. However, Li dendrite growth induces a significant safety concerns in these batteries. Here, a multifunctional separator through coating a thin electronic conductive film on one side of the conventional polymer separator facing the Li anode is proposed for the purpose of Li dendrite suppression and cycling stability improvement. The ultrathin Cu film on one side of the polyethylene support serves as an additional conducting agent to facilitate electrochemical stripping/deposition of Li metal with less accumulation of electrically isolated or “dead” Li. Furthermore, its electrically conductive nature guides the backside plating of Li metal and modulates the Li deposition morphology via dendrite merging. In addition, metallic Cu film coating can also improve thermal stability of the separator and enhance the safety of the batteries. Due to its unique beneficial features, this separator enables stable cycling of Li metal anode with enhanced Coulombic efficiency during extended cycles in Li metal batteries and increases the lifetime of Li metal anode by preventing short‐circuit failures even under extensive Li metal deposition.
Slow‐Photon‐Effect‐Induced Photoelectrical‐Conversion Efficiency Enhancement for Carbon‐Quantum‐Dot‐Sensitized Inorganic CsPbBr3 Inverse Opal Perovskite Solar Cells
Authors: Zhou Shujie , Tang Rui , Yin Longwei
Published: October 2017

All‐inorganic cesium lead halide perovskite is suggested as a promising candidate for perovskite solar cells due to its prominent thermal stability and comparable light absorption ability. Designing textured perovskite films rather than using planar‐architectural perovskites can indeed optimize the optical and photoelectrical conversion performance of perovskite photovoltaics. Herein, for the first time, this study demonstrates a rational strategy for fabricating carbon quantum dot (CQD‐) sensitized all‐inorganic CsPbBr3 perovskite inverse opal (IO) films via a template‐assisted, spin‐coating method. CsPbBr3 IO introduces slow‐photon effect from tunable photonic band gaps, displaying novel optical response property visible to naked eyes, while CQD inlaid among the IO frameworks not only broadens the light absorption range but also improves the charge transfer process. Applied in the perovskite solar cells, compared with planar CsPbBr3, slow‐photon effect of CsPbBr3 IO greatly enhances the light utilization, while CQD effectively facilitates the electron–hole extraction and injection process, prolongs the carrier lifetime, jointly contributing to a double‐boosted power conversion efficiency (PCE) of 8.29% and an increased incident photon‐to‐electron conversion efficiency of up to 76.9%. The present strategy on CsPbBr3 IO to enhance perovskite PCE can be extended to rationally design other novel optoelectronic devices.
Improving Efficiency and Stability of Perovskite Solar Cells by Modifying Mesoporous TiO2–Perovskite Interfaces with Both Aminocaproic and Caproic acids
Authors: Chen Ruihao , Cao Jing , Wu Youyunqi , Jing Xiaojing , Wu Binghui , Zheng Nanfeng
Published: October 2017

In the field of photovoltaic industry, organolead halide perovskite solar cells (PSCs) as cleaner and cheaper photo‐voltaic devices have shown a bright prospect with power conversion efficiency (PCE) rapidly climbing from 3.8% to certified 22.1% in a few years. Interface engineering has been proven to be highly effective to solve the instability‐to‐moisture issue and enhance the performance of PSCs. Here, this work develops a simple and easy‐proceeding strategy that depositing both aminocaproic acid [H2NCH2(CH2)4COOH, abbreviated as AmCA] and caproic acid [CH3(CH2)4COOH, CA] at the mesoporous TiO2/perovskite interface leads to significant enhancement in both the efficiency and stability of PSCs. These two organic modifiers work synergistically to enhance the overall performance of PSCs by promoting electron transfer through the interaction between amino groups on AmCA and perovskite layer, and resisting moisture with alkyl chains from CA. The champion efficiency of modified cells reaches 18.2%, with an average PCE of 17.5% in reliable reproducibility, with significant improvement in stability under 50 ± 5% relative humidity in air. The developed simple interfacial modification approach should be effective to enhance both efficiency and stability of PSCs with other architectures as well. More importantly, this scenario may provide insight into the commercialization of perovskite solar cells in the not‐too‐distant future.
Self‐Powered UV Photodetector Array Based on P3HT/ZnO Nanowire Array Heterojunction
Authors: Ouyang Bangsen , Zhang Kewei , Yang Ya
Published: October 2017

Self‐powered photodetector array based on organic–inorganic heterojunction is extremely suitable for light imaging applications, owing to their unique flexibility and stability. Here, a self‐powered ultraviolet (UV) photodetector based on p‐P3HT/n‐ZnO nanowire array heterojunction is demonstrated, which exhibits photoconductive gain of 4.2 × 10−4, responsivity of 125 µA W−1, specific detectivity of 3.7 × 107 Jones, and response/recovery speed of less than 100 ms at a low light intensity of 0.84 mW cm−2 for λ = 365 nm. The responsivity of this photodetector can be further enhanced by ≈21.9% under a temperature difference of −15.4 °C, owing to the thermo‐phototronic effect. Moreover, a photodetector array with 16 pixels is successfully demonstrated for light imaging of complex patterns, such as number‐shape and cross‐shape. This study provides a practical solution to achieve large‐scale UV imaging by integrating inorganic–organic hybrid photodetector into self‐powered array configuration.
Bioinspired Anti‐Moiré Random Grids via Patterning Foams
Authors: Li Zheng , Huang Zhandong , Yang Qiang , Su Meng , Zhou Xue , Li Huizeng , Li Lihong , Li Fengyu , Song Yanlin
Published: October 2017

Transparent conductors with specific patterns are essential for touch screens as sensing electrodes. Among them, metal grids are a kind of optimal alternative for traditional transparent conductors, while moiré patterns hinder metal grids in the application of display planes. Nevertheless, random or aperiodic pattern grids can avoid the patterns. A series of bioinspired random (BR) grids is demonstrated that can avoid moiré patterns and exhibit great optoelectronic performance comparable to indium tin oxide (ITO). The BR grids comprising random hexagons originate from biological networks with line arrangements that are random and aperiodic. They are fabricated through a controllable and highly efficient method of patterning foams, and are composed of close‐packed silver nanoparticles (AgNPs). This type of grid has potential to extend applications of high‐transparent functional devices.
The Next‐Generation of Nonlinear Optical Materials: Rb3Ba3Li2Al4B6O20F—Synthesis, Characterization, and Crystal Growth
Authors: Yu Hongwei , Young Joshua , Wu Hongping , Zhang Weiguo , Rondinelli James M. , Halasyamani Shiv
Published: October 2017

Nonlinear optical (NLO) materials are of intense academic and technological interest attributable to their ability to generate coherent radiation over a range of different wavelengths. The requirements for a viable NLO material are rather strict, and their discovery has mainly been serendipitous. This study reports synthesis, characterization, and, most importantly, growth of large single crystals of a technologically viable NLO material—Rb3Ba3Li2Al4B6O20F. Through the judicious selection of cations, Rb3Ba3Li2Al4B6O20F exhibits a 3D structure that facilitates the growth of large single crystals along the optical axis direction. Measurements on these crystals indicate that Rb3Ba3Li2Al4B6O20F exhibits a moderate birefringence of 0.057 at 1064 nm enabling Type I phase‐matching down to 243 nm. Theoretical calculations indicate the symmetry adapted mode displacement (SAMD) parameter scales with the second‐harmonic generation intensity.
Iridium‐Catalyzed Regio‐ and Stereoselective C‐H Oxidative Reaction to (Z)‐3‐Arylidene‐2‐oxindole Imides under Neutral Conditions
Authors: Tu Zhikai , Tan Jie , Chen Zhiyuan , Tu Tao
Published: October 2017

Unsymmetrical 3‐arylidene‐2‐oxindoles are useful pharmacophores for many clinical drugs or intermediates in alkaloids synthesis. An IridiumIII‐catalyzed sequential C−H oxidative reaction of 2‐indolyl enamides has been established. This protocol utilized α,α‐dimethyl benzylhydroperoxide as the oxidant and silver fluoride as a key promoter, to provide a wide range of (Z)‐3‐arylidene‐2‐oxindole imides in moderate to good yields, together with good regio‐ and stereoselectivity. The silver fluoride was found to function as a base to facilitate the generation of the active Iridium catalyst species. The resulting (Z)‐3‐arylidene‐2‐oxindole imides could be further transformed to various valuable derivatives. Mechanistically, radical‐process was excluded from this C−H oxidative transformation, and a 6‐membered cationic iridacycle intermediate was proposed to be involved in the catalytic cycle.

magnified image
Synergistic effects of sulfur poisoning and gas diffusion on polarization loss in anodes of solid oxide fuel cells
Authors: Niu Yinghua , Lv Weiqiang , Wei Zhaohuan , Huo Weirong , He Weidong
Published: October 2017

Poisoning effects of sulfur compounds on the performances of solid oxide fuel cells are non‐trivial. However, the synergistic effects of gas diffusion, adsorption, desorption and reaction in anodes are typically neglected. In this work, an analytical model is derived to quantitatively evaluate the poisoning effects of H2S. The results show that sulfur poisoning correlates closely with inefficient gas diffusion for small anode pore size, small porosity/tortuosity, and low working temperatures. As compared with concentration polarization, H2S‐diffusion‐induced activation polarization in thin anodes with a large
is detrimental, especially for low‐temperature operations with a high H2S concentration and a low current density. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1127–1134, 2018
1(3)‐Formyl‐β‐carbolines: Potential Aldo‐X Precursors for the Synthesis of β‐Carboline‐Based Molecular Architectures
Authors: Devi Nisha , Kumar Sunit , Pandey Satyendra Kumar , Singh Virender
Published: October 2017

β‐Carboline, a privileged scaffold in the alkaloid family, has a broad spectrum of medicinal properties and is found in several commercial drugs, such as tadalafil, cipargamin, and abecarnil. Owing to the immense pharmacological importance of β‐carboline derivatives, their synthesis has been one of the frontier areas of research in recent years. In this context, 1(3)‐formyl‐9H‐β‐carbolines are promising “aldo‐X” bifunctional building blocks (AXB3s) that offer alternate avenues for the diversity‐oriented synthesis of β‐carboline derivatives. This Focus Review is an assimilation of recent literature (2011–2017) pertaining to the synthesis and applications of 1(3)‐formyl‐β‐carbolines for the construction of β‐carboline‐tethered and ‐fused molecular architectures. In addition, the medicinal potential of β‐carboline derivatives has been highlighted.
Pd‐Catalyzed Cyclopropanation Reaction of Aliphatic Ketones with Monosubstituted Allyl Reagents
Authors: Huang Jian‐Qiang , Zhao Jing‐Feng , Yang Zhen , Ding Chang‐Hua , Hou Xue‐Long , Peng Xiao‐Shui , Wong Henry Nai Ching
Published: October 2017

A Pd‐catalyzed cyclopropanation reaction with aliphatic ketones as nucleophiles using a modified pyridine‐NHC ligand was achieved. The reaction afforded the corresponding cyclopropanes in moderate to good yields with high cyclopropane/allylation selectivity.
Stroke‐induced chronic systolic dysfunction driven by sympathetic overactivity
Authors: Bieber Michael , Werner Rudolf A. , Tanai Edit , Hofmann Ulrich , Higuchi Takahiro , Schuh Kai , Heuschmann Peter U. , Frantz Stefan , Ritter Oliver , Kraft Peter , Kleinschnitz Christoph
Published: October 2017

Objective

Cardiac diseases are established risk factors for ischemic stroke incidence and severity. Conversely, there is increasing evidence that brain ischemia can cause cardiac dysfunction. The mechanisms underlying this neurogenic heart disease are incompletely understood. Although it is established that ischemic stroke is associated with cardiac arrhythmias, myocardial damage, elevated cardiac enzymes, and plasma catecholamines in the acute phase, nothing is known about the delayed consequences of ischemic stroke on cardiovascular function.

Methods

To determine the long‐term cardiac consequences of a focal cerebral ischemia, we subjected young and aged mice to a 30‐minute transient middle cerebral artery occlusion and analyzed cardiac function by serial transthoracic echocardiography and hemodynamic measurements up to week 8 after surgery. Finally, animals were treated with metoprolol to evaluate a pharmacologic treatment option to prevent the development of heart failure.

Results

Focal cerebral ischemia induced a long‐term cardiac dysfunction with a reduction in left ventricular ejection fraction and an increase in left ventricular volumes; this development was associated with higher peripheral sympathetic activity. Metoprolol treatment prevented the development of chronic cardiac dysfunction by decelerating extracellular cardiac remodeling and inhibiting sympathetic signaling relevant to chronic autonomic dysfunction.

Interpretation

Focal cerebral ischemia in mice leads to the development of chronic systolic dysfunction driven by increased sympathetic activity. If these results can be confirmed in a clinical setting, treating physicians should be attentive to clinical signs of heart failure in every patient after ischemic stroke. Therapeutically, the successful β‐blockade with metoprolol in mice could also have future clinical implications. Ann Neurol 2017;82:729–743
Das Cysteinom der Proteinkinasen als Zielstruktur in der Arzneistoffentwicklung
Authors: Chaikuad Apirat , Koch Pierre , Laufer Stefan A. , Knapp Stefan
Published: October 2017

Wirkstoffe, die ihre Wirkung über die Ausbildung einer kovalenten Bindung entfalten, repräsentieren einen beachtlichen Anteil unseres Arsenals an effektiven Arzneistoffen. Allerdings wurde die aufwendige Entwicklung kovalenter Inhibitoren wegen Sicherheitsbedenken bis vor kurzem nur als eine wenig attraktive Strategie im rationalen Wirkstoffdesign angesehen. Die kürzliche Zulassung von vier kovalenten Kinaseinhibitoren und die Entwicklung hochpotenter kovalenter Kinasehemmstoffe mit bemerkenswerter Selektivität erhöhte das Interesse in der industriellen und akademischen Forschung maßgeblich und bestätigte das Konzept der kovalenten Kinasehemmung für klinische Anwendungen. Die Häufigkeit von Cysteinen an verschiedenen Positionen innerhalb und in der Nähe des aktiven Zentrums legt nahe, dass ein wesentlicher Teil der Kinasen durch kovalente Inhibitoren adressiert werden kann. In diesem Aufsatz geben wir eine Übersicht über die neuesten Entwicklungen in diesem schnell wachsenden Gebiet und heben die einzigartigen Möglichkeiten und Herausforderungen dieser Strategie hervor.
Effects of Bithiophene Imide Fusion on the Device Performance of Organic Thin‐Film Transistors and All‐Polymer Solar Cells
Authors: Wang Yingfeng , Yan Zhenglong , Guo Han , Uddin Mohammad Afsar , Ling Shaohua , Zhou Xin , Su Huimin , Dai Junfeng , Woo Han Young , Guo Xugang
Published: October 2017

Two new bithiophene imide (BTI)‐based n‐type polymers were synthesized. f‐BTI2‐FT based on a fused BTI dimer showed a smaller band gap, a lower LUMO, and higher crystallinity than s‐BTI2‐FT containing a BTI dimer connected through a single bond. s‐BTI2‐FT exhibited a remarkable electron mobility of 0.82 cm2 V−1 s−1, and f‐BTI2‐FT showed a further improved mobility of 1.13 cm2 V−1 s−1 in transistors. When blended with the polymer donor PTB7‐Th, f‐BTI2‐FT‐based all‐polymer solar cells (all‐PSCs) attained a PCE of 6.85 %, the highest value for an all‐PSC not based on naphthalene (or perylene) diimide polymer acceptors. However, s‐BTI2‐FT all‐PSCs showed nearly no photovoltaic effect. The results demonstrate that f‐BTI2‐FT is one of most promising n‐type polymers and that ring fusion offers an effective approach for designing polymers with improved electrical properties.
Selektive C‐H‐Bindungsaktivierung durch eine Kaskade aus Photochemie und Biokatalyse
Authors: Zhang Wuyuan , Burek Bastien O. , Fernández‐Fueyo Elena , Alcalde Miguel , Bloh Jonathan Z. , Hollmann Frank
Published: October 2017

Selektive Oxyfunktionalisierungen von inerten C‐H‐Bindungen können unter milden Bedingungen durch den Einsatz von Peroxygenasen erreicht werden. Dieser Ansatz wird jedoch durch die schlechte Stabilität der Enzyme in Anwesenheit stöchiometrischer Mengen des Oxidationsmittels Wasserstoffperoxid erschwert. Hier zeigen wir, dass sich anorganische Photokatalysatoren wie goldbeladenes Titandioxid zur effizienten Bereitstellung geeigneter Mengen an H2O2 durch reduktive Aktivierung von Umgebungssauerstoff und simultaner Oxidation von Methanol eignen und gleichzeitig eine hohe Reaktivität und Stabilität des Enzyms gewährleisten. Mithilfe dieses Ansatzes konnte die stereoselektive Hydroxylierung von Ethylbenzol zu (R)‐1‐Phenylethanol in hoher Enantioselektivität (>98 % ee) und sehr hoher katalytischer Produktivität (TON>71.000) erreicht werden.
Electrostatic‐Assisted Liquefaction of Porous Carbons
Authors: Li Peipei , Schott Jennifer A. , Zhang Jinshui , Mahurin Shannon M. , Sheng Yujie , Qiao Zhen‐An , Hu Xunxiang , Cui Guokai , Yao Dongdong , Brown Suree , Zheng Yaping , Dai Sheng
Published: October 2017

Porous liquids are a newly developed porous material that combine unique fluidity with permanent porosity, which exhibit promising functionalities for a variety of applications. However, the apparent incompatibility between fluidity and permanent porosity makes the stabilization of porous nanoparticle with still empty pores in the dense liquid phase a significant challenging. Herein, by exploiting the electrostatic interaction between carbon networks and polymerized ionic liquids, we demonstrate that carbon‐based porous nanoarchitectures can be well stabilized in liquids to afford permanent porosity, and thus opens up a new approach to prepare porous carbon liquids. Furthermore, we hope this facile synthesis strategy can be widely applicated to fabricate other types of porous liquids, such as those (e.g., carbon nitride, boron nitride, metal–organic frameworks, covalent organic frameworks etc.) also having the electrostatic interaction with polymerized ionic liquids, evidently advancing the development and understanding of porous liquids.
Dimethylamin als Substrat in Hydroaminoalkylierungsreaktionen
Authors: Bielefeld Jens , Doye Sven
Published: October 2017

Übergangsmetallkatalysierte Hydroaminoalkylierungen von Alkenen haben im vergangenen Jahrzehnt große Fortschritte gemacht und entwickeln sich zu einer greifbaren Alternative zur industriellen Synthese von Aminen durch Hydroformylierung von Alkenen und nachfolgende reduktive Aminierung. Ein großes Hindernis war in der Vergangenheit, dass Methylamin und Dimethylamin als industriell wichtigste Amine in diesen Reaktionen nicht zufriedenstellend umgesetzt werden konnten. Wir zeigen hier erstmals die erfolgreiche Umsetzung von Dimethylamin in katalytischen Hydroaminoalkylierungen von Alkenen mit guten Ausbeuten, sowie die Anwendbarkeit für eine Reihe verschiedener Alkene und die Toleranz gegenüber verschiedenen funktionellen Gruppen. Zusätzlich präsentieren wir die katalytische Dihydroaminoalkylierungsreaktion mit Dimethylamin, über die nie zuvor berichtet wurde.
Catalytic Enantioselective Synthesis of Mariline A and Related Isoindolinones through a Biomimetic Approach
Authors: Min Chang , Lin Yingfu , Seidel Daniel
Published: October 2017

The catalytic enantioselective synthesis of isoindolinones was achieved through the condensation of 2‐acyl‐benzaldehydes and anilines. In the presence of 1 mol % of a chiral phosphoric acid catalyst, reactions reach completion within 10 min and provide products with up to 98 % ee. Anilines with an ortho t‐butyl group form atropisomeric products, thereby enabling the simultaneous generation of axial and point chirality from two achiral substrates. This method was applied to the first synthesis of mariline A.
Lithium Azide as an Electrolyte Additive for All‐Solid‐State Lithium–Sulfur Batteries
Authors: Eshetu Gebrekidan Gebresilassie , Judez Xabier , Li Chunmei , Bondarchuk Oleksandr , Rodriguez‐Martinez Lide M. , Zhang Heng , Armand Michel
Published: October 2017

Of the various beyond‐lithium‐ion battery technologies, lithium–sulfur (Li–S) batteries have an appealing theoretical energy density and are being intensely investigated as next‐generation rechargeable lithium‐metal batteries. However, the stability of the lithium‐metal (Li°) anode is among the most urgent challenges that need to be addressed to ensure the long‐term stability of Li–S batteries. Herein, we report lithium azide (LiN3) as a novel electrolyte additive for all‐solid‐state Li–S batteries (ASSLSBs). It results in the formation of a thin, compact and highly conductive passivation layer on the Li° anode, thereby avoiding dendrite formation, and polysulfide shuttling. It greatly enhances the cycling performance, Coulombic and energy efficiencies of ASSLSBs, outperforming the state‐of‐the‐art additive lithium nitrate (LiNO3).
Mild Reduction of Phosphine Oxides with Phosphites To Access Phosphines
Authors: Li Peng , Wischert Raphael , Métivier Pascal
Published: October 2017

A new method for the iodine‐catalyzed reduction of phosphine oxides with phosphites at room temperature is reported. The mild reaction conditions, scalability, and simple purification requirements render it a method of choice for the large‐scale production and facile regeneration of a variety of phosphines. Mechanistic studies, supported by DFT calculations of the oxygen transfer between the starting phosphine oxide and the phosphite reagent, are also presented. Such transmutations of phosphorus species were previously unknown.
Decoupled Thermo‐ and pH‐Responsive Hydrogel Microspheres Cross‐Linked by Rotaxane Networks
Authors: Kureha Takuma , Aoki Daichi , Hiroshige Seina , Iijima Keisuke , Aoki Daisuke , Takata Toshikazu , Suzuki Daisuke
Published: October 2017

Rotaxane cross‐linked (RC) microgels that exhibit a decoupled thermo‐ and pH‐responsive volume transition were developed. The pH‐induced changes of the aggregation/disaggregation states of cyclodextrin in the RC networks were used to control the swelling capacity of the entire microgels. Different from conventional thermo‐ and pH‐responsive microgels, which are usually obtained from copolymerizations involving charged monomers, the RC microgels respond to temperature as intended, even in the presence of charged functional molecules such as dyes in the microgel dispersion. The results of this study should lead to new applications, including drug delivery systems that require a retention of their smart functions even in environments that may contain foreign ions, for example, in in vivo experiments.
The Cysteinome of Protein Kinases as a Target in Drug Development
Authors: Chaikuad Apirat , Koch Pierre , Laufer Stefan A. , Knapp Stefan
Published: October 2017

Drugs that function through covalent bond formation represent a considerable fraction of our repository of effective medicines but safety concerns and the complexity of developing covalent inhibitors has rendered covalent targeting a less attractive strategy for rational drug design. The recent approval of four covalent kinase inhibitors and the development of highly potent covalent kinase probes with exceptional selectivity has raised significant interest in industry and academic research and validated the concept of covalent kinase targeting for clinical applications. The abundance of cysteines at diverse positions in and around the kinase active site suggests that a large fraction of kinases can be targeted by covalent inhibitors. Herein, we review recent developments of this rapidly growing area in kinase drug development and highlight the unique opportunities and challenges of this strategy.
Transient Behavior of the Metal Interface in Lithium Metal–Garnet Batteries
Authors: Fu Kun (Kelvin) , Gong Yunhui , Fu Zhezhen , Xie Hua , Yao Yonggang , Liu Boyang , Carter Marcus , Wachsman Eric , Hu Liangbing
Published: October 2017

The interface between solid electrolytes and Li metal is a primary issue for solid‐state batteries. Introducing a metal interlayer to conformally coat solid electrolytes can improve the interface wettability of Li metal and reduce the interfacial resistance, but the mechanism of the metal interlayer is unknown. In this work, we used magnesium (Mg) as a model to investigate the effect of a metal coating on the interfacial resistance of a solid electrolyte and Li metal anode. The Li–Mg alloy has low overpotential, leading to a lower interfacial resistance. Our motivation is to understand how the metal interlayer behaves at the interface to promote increased Li‐metal wettability of the solid electrolyte surface and reduce interfacial resistance. Surprisingly, we found that the metal coating dissolved in the molten piece of Li and diffused into the bulk Li metal, leading to a small and stable interfacial resistance between the garnet solid electrolyte and the Li metal. We also found that the interfacial resistance did not change with increase in the thickness of the metal coating (5, 10, and 100 nm), due to the transient behavior of the metal interface layer.
Dimethylamine as a Substrate in Hydroaminoalkylation Reactions
Authors: Bielefeld Jens , Doye Sven
Published: October 2017

Transition‐metal‐catalyzed hydroaminoalkylations of alkenes have made great progress over the last decade and are heading to become a viable alternative to the industrial synthesis of amines through hydroformylation of alkenes and subsequent reductive amination. In the past, one major obstacle of this progress has been an inability to apply these reactions to the most important amines, methylamine and dimethylamine. Herein, we report the first successful use of dimethylamine in catalytic hydroaminoalkylations of alkenes with good yields. We also report applicability for a variety of alkenes to show the tolerance of the reaction towards different functional groups. Additionally, we present a catalytic dihydroaminoalkylation reaction using dimethylamine, which has never been reported before.
Assembly, Thermodynamics, and Structure of a Two‐Wheeled Composite of a Dumbbell‐Shaped Molecule and Cylindrical Molecules with Different Edges
Authors: Matsuno Taisuke , Kamata Sho , Sato Sota , Yokoyama Atsutoshi , Sarkar Parantap , Isobe Hiroyuki
Published: October 2017

A carbonaceous dumbbell was able to spontaneously glue two tubular receptors to form a unique two‐wheeled composite through van der Waals interactions, thus forcing the wheel components into contact with each other at the edges. In the present study, two tubular receptors with enantiomeric carbon networks were assembled on the dumbbell joint, and the handedness of the receptors was discriminated, thus leading to the self‐sorting of homomeric receptors from a mixture of enantiomeric tubes. The crystal structures of the composites revealed the structural origins of the molecular recognition driven by van der Waals forces as well as the presence of a columnar array of C120 molecules in a 1:1 composite.
Polyaniline‐grafted polyurethane coatings for corrosion protection of mild steel surfaces
Authors: Karmakar Himadri S. , Arukula Ravi , Thota Apparao , Narayan Ramanuj , Rao Chepuri R. K.
Published: October 2017

We report the superior corrosion‐resistant properties of conducting polyurethane networks of polyaniline (PANI), poly‐m‐aminophenol (PmAP), and poly‐o‐anisidine (PoA) coated on mild steel panels. These networks were prepared by blending conducting polyanilines with isocyanate‐containing prepolyurethanes. Free‐standing polyurethane films were obtained after a moisture cure for several days to ensure complete reaction of the excess isocyanate. The films were electrochemically active with conductivity in the range of 10−2 to 10−3 S/cm. The solution blends and formed films were characterized by infrared, ultraviolet, thermogravimetric analysis, and differential scanning calorimetry. Electrochemical corrosion studies of the coated films on mild steel panels showed excellent corrosion protection in the following order: PU‐PANI > PU‐PmAP > PU‐PoA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45806.