bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Arylstannanes via Palladium‐Catalyzed Decarbonylative Coupling of Aroyl Fluorides
Authors: Kayumov Muzaffar , Zhao Jian‐Nan , Mirzaakhmedov Sharafitdin , Wang Dong‐Yu , Zhang Ao 
Published: October 2019

AbstractAryl stannanes are valuable precursors in organic transformations, but their synthetic methods are limited. Here we present a Pd‐catalyzed decarbonylative stannylation of acid fluorides in the absence of exogenous base. Various aryl stannanes were efficiently prepared from bench‐stable transition metal catalyst and ligand with broad functional group compatibility and substrate scope including natural products and pharmaceuticals. This protocol was also successfully used to a late‐stage diversification of an existing uricosuric drug probenecid.magnified image
Hierarchical Branched Mesoporous TiO2–SnO2 Nanocomposites with Well‐Defined n–n Heterojunctions for Highly Efficient Ethanol Sensing
Authors: Zhao Tao , Qiu Pengpeng , Fan Yuchi , Yang Jianping , Jiang Wan , Wang Lianjun , Deng Yonghui , Luo Wei 
Published: October 2019

AbstractThe direct assembly of functional nanoparticles into a highly crystalline mesoporous semiconductor with oriented configurations is challenging but of significance. Herein, an evaporation induced oriented co‐assembly strategy is reported to incorporate SnO2 nanocrystals (NCs) into a 3D branched mesoporous TiO2 framework by using poly(ethylene oxide)‐block‐polystyrene (PEO‐b‐PS) as the template, SnO2 NCs as the direct tin source, and titanium butoxide (TBOT) as the titania precursor. Owing to the combined properties of ultrasmall particle size (3–5 nm), excellent dispersibility and presence of abundant hydroxyl groups, SnO2 NCs can easily interact with PEO block of the template through hydrogen bonding and co‐assemble with hydrolyzed TBOT to form a novel hierarchical branched mesoporous structure (SHMT). After calcination, the obtained composites exhibit a unique 3D flower‐like structure, which consists of numerous mesoporous rutile TiO2 branches with uniform cylindrical mesopores (≈9 nm). More importantly, the SnO2 NCs are homogeneously distributed in the mesoporous TiO2 matrix, forming numerous n–n heterojunctions. Due to the unique textual structures, the SHMT‐based gas sensors show excellent gas sensing performance with fast response/recovery dynamics, high sensitivity, and selectivity toward ethanol.
Flow‐based reactor design for the continuous production of polymeric nanoparticles
Authors: Bovone Giovanni , Guzzi Elia A. , Tibbitt Mark W. 
Published: October 2019

AbstractPolymeric nanoparticles (NPs) are versatile and effective drug delivery systems (DDS) that can be produced via nanoprecipitation of block copolymers. Yet, translation into clinical products has been limited. Thus, methods for NP production that enable rapid formulation screening and continuous production are needed. Toward this end, we engineered a coaxial jet mixer (CJM) for controlled and continuous nanoprecipitation in flow. The CJM enabled continuous assembly of poly(ethylene glycol)‐block‐polylactide NPs with various co‐solvents and was compared to batch nanoprecipitation. Other fabricated microfluidic devices were suitable for small scale formulation screening but more limited in scalable and continuous processes. In contrast, the CJM was tolerant to all water‐miscible solvents tested, enabled formulation screening, and scalable production of NPs and DDS. In total, the CJM provides a complementary approach to the process engineering of polymeric NP formation that can be used broadly for formulation screening and production.
Activation and deactivation of the commercial‐type CuO–Cr2O3–Fe2O3 high temperature shift catalyst
Authors: Zhu Minghui , Tian Pengfei , Chen Jiacheng , Ford Michael E. , Xu Jing , Wachs Israel E. , Han Yi‐Fan 
Published: October 2019

AbstractThis work elucidates the structural evolution of a commercial‐type iron oxide‐based high temperature water–gas shift (HT‐WGS) catalyst during activation and deactivation stages. The findings highlight the importance of Cu–FeO
x interfaces. Based on the new insights, future improvement of commercial iron‐based catalysts should focus on stabilization of the active Cu–FeO
x interface. Much effort has been devoted to understanding the structure, mechanism, and promotion of the commercial‐type CuO–Cr2O3–Fe2O3 catalyst for the high temperature water–gas shift (HT‐WGS) reaction. However, structural evolution of the catalyst during the activation and deactivation stages was rarely reported. Herein, catalyst characterization, temperature‐programmed studies, and kinetic analysis were conducted on iron oxide‐based HT‐WGS catalysts. Addition of Cu was found to accelerate both the bulk (Fe2O3 → Fe3O4) and surface (active FeO
x–Cu interface) transformations during the catalyst activation stage. During catalyst deactivation, Cu accelerated both sintering of the Fe3O4 bulk phase and unfavorable encapsulation of the metallic Cu particles with a substantial FeO
x overlayer. The loss of the initial active Cu–FeO
x interfacial sites reversed the promotional effect of Cu.
Phase I/II multisite trial of optimally dosed clofarabine and low‐dose TBI for hematopoietic cell transplantation in acute myeloid leukemia
Authors: Krakow Elizabeth F. , Gyurkocza Boglarka , Storer Barry E. , Chauncey Thomas R. , McCune Jeannine S. , Radich Jerald P. , Bouvier Michelle E. , Estey Elihu H. , Storb Rainer , Maloney David G , Sandmaier Brenda M. 
Published: October 2019

AbstractClofarabine is an immunosuppressive purine nucleoside analog that may have better anti‐leukemic activity than fludarabine. We performed a prospective phase I/II multisite trial of clofarabine with 2 Gy total body irradiation as non‐myeloablative conditioning for allogeneic hematopoietic cell transplantation in adults with acute myeloid leukemia who were unfit for more intense regimens. Our main objective was to improve the 6‐month relapse rate following non‐myeloablative conditioning, while maintaining historic rates of non‐relapse mortality (NRM) and engraftment. Forty‐four patients, 53 to 74 (median: 69) years, were treated with clofarabine at 150 to 250 mg/m2, of whom 36 were treated at the maximum protocol‐specified dose. One patient developed multifactorial acute kidney injury and another developed multiorgan failure, but no other grade 3 to 5 non‐hematologic toxicities were observed. All patients fully engrafted. The 6‐month relapse rate was 16% (95% CI, 5%‐27%) among all patients and 14% (95% CI, 3%‐26%) among high‐risk patients treated at the maximum dose, meeting the pre‐specified primary efficacy endpoint. Overall survival was 55% (95% CI, 40%‐70%) and leukemia‐free survival was 52% (95% CI, 37%‐67%) at 2 years. Compared to a historical high‐risk cohort treated with the combination of fludarabine at 90 mg/m2 and 2 Gy TBI, protocol patients treated with the clofarabine‐TBI regimen had lower rates of overall mortality (HR of 0.50, 95% CI, 0.28‐0.91), disease progression or death (HR 0.48, 95% CI, 0.27‐0.85), and morphologic relapse (HR 0.30, 95% CI, 0.13‐0.69), and comparable NRM (HR 0.85, 95% CI 0.36‐2.00). The combination of clofarabine with TBI warrants further investigation in patients with high‐risk AML.
Alzheimer's disease development in adults with Down syndrome: Caregivers' perspectives
Authors: Ilacqua Alexandra , Benedict Jason , Shoben Abigail , Skotko Brian G. , Matthews Theodora , Benson Betsey , Allain Dawn C. 
Published: October 2019

AbstractResearch about Alzheimer's disease (AD) in individuals with Down syndrome (DS) has predominantly focused on the underlying genetics and neuropathology. Few studies have addressed how AD risk impacts caregivers of adults with DS. This study aimed to explore the perceived impact of AD development in adults with DS on caregivers by assessing caregiver knowledge, concerns, effect on personal life, and resource utilization via a 40‐question (maximum) online survey. Survey distribution by four DS organizations and two DS clinics resulted in 89 caregiver respondents. Only 28 caregivers correctly answered all three AD knowledge questions. Caregivers gave an average AD concern rating of 5.30 (moderately concerned) and an average impact of possible diagnosis rating of 6.28 (very strong impact), which had a significant negative correlation with the age of the adult with DS (p = .009). Only 33% of caregivers reported utilization of resources to gain more information about the AD and DS association, with low levels of perceived usefulness. Our data reveal caregivers' misconceptions about AD development in DS, underutilization of available resources, and substantial concerns and perceived impacts surrounding a possible AD diagnosis. This study lays the foundation for how the medical community can better serve caregivers of aging adults with DS.
Conversion of Knill–Laflamme–Milburn Entanglement to Greenberger–Horne–Zeilinger Entanglement
Authors: Shen Cai‐Peng , Xiu Xiao‐Ming , Dong Li , Zhu Xiao‐Yu , Chen Li , Liang Erjun , Yan Lei‐Lei , Su Shi‐Lei 
Published: October 2019

AbstractSchemes for converting photonic polarized‐entangled Knill–Laflamme–Milburn (KLM) states to Greenberger–Horne–Zeilinger (GHZ) states are proposed using weak cross‐Kerr nonlinearity and X‐quadrature homodyne measurement. Analyses show that the two‐qubit (Bell state) and three‐qubit conversion cases have very high fidelities and close‐to‐unity probabilities. The conversion processes are robust against photon loss. The schemes linking these two entangled states may be helpful to the study of quantum information processing based on them.
Photocaged Quinone Methide Crosslinkers for Light‐Controlled Chemical Crosslinking of Protein–Protein and Protein–DNA Complexes
Authors: Liu Jun , Cai Lingchao , Sun Wei , Cheng Rujin , Wang Nanxi , Jin Ling , Rozovsky Sharon , Seiple Ian B. , Wang Lei 
Published: October 2019

AbstractSmall‐molecule crosslinkers are invaluable for probing biomolecular interactions and for crosslinking mass spectrometry. Existing chemical crosslinkers target only a small selection of amino acids, while conventional photo‐crosslinkers target almost all residues non‐specifically, complicating data analysis. Herein, we report photocaged quinone methide (PQM)‐based crosslinkers that target nine nucleophilic residues through Michael addition, including Gln, Arg, and Asn, which are inaccessible to existing chemical crosslinkers. PQM crosslinkers were used in vitro, in Escherichia coli, and in mammalian cells to crosslink dimeric proteins and endogenous membrane receptors. The heterobifunctional crosslinker NHQM could crosslink proteins to DNA, for which few crosslinkers exist. The photoactivatable reactivity of these crosslinkers and their ability to target multiple amino acids will enhance the use of chemical crosslinking for studies of protein–protein and protein–DNA networks and for structural biology.
Direct Identification of Acetaldehyde Formation and Characterization of the Active Site in the [VPO4].+/C2H4 Couple by Gas‐Phase Vibrational Spectroscopy
Authors: Li Ya‐Ke , Debnath Sreekanta , Schlangen Maria , Schöllkopf Wieland , Asmis Knut R. , Schwarz Helmut 
Published: October 2019

AbstractThe gas‐phase reaction of the heteronuclear oxide cluster [VPO4].+ with C2H4 is studied under multiple collision conditions at 150 K using cryogenic ion‐trap vibrational spectroscopy combined with electronic structure calculations. The exclusive formation of acetaldehyde is directly identified spectroscopically and discussed in the context of the underlying reaction mechanism. In line with computational predictions it is the terminal P=O and not the V=O unit that provides the oxygen atom in the barrier‐free thermal C2H4→CH3CHO conversion. Interestingly, in the course of the reaction, the emerging CH3CHO product undergoes a rather complex intramolecular migration, coordinating eventually to the vanadium center prior to its liberation. Moreover, the spectroscopic structural characterization of neutral C2H4O deserves special mentioning as in most, if not all, ion/molecule reactions, the neutral product is usually only indirectly identified.
Singlet Fission in Pyrene‐Fused Azaacene Dimers
Authors: Mora‐Fuentes Juan P. , Papadopoulos Ilias , Thiel Dominik , Álvarez‐Boto Roberto , Cortizo‐Lacalle Diego , Clark Timothy , Melle‐Franco Manuel , Guldi Dirk M. , Mateo‐Alonso Aurelio 
Published: October 2019

AbstractSinglet fission has emerged as a promising strategy to avoid the loss of extra energy through thermalization in solar cells. A family of dimers consisting of nitrogen‐doped pyrene‐fused acenes that undergo singlet fission with triplet quantum yields as high as 125 % are presented. They provide new perspectives for nitrogenated polycyclic aromatic hydrocarbons and for the design of new materials for singlet fission.
An Engineered Superhydrophilic/Superaerophobic Electrocatalyst Composed of the Supported CoMoSx Chalcogel for Overall Water Splitting
Authors: Shan Xinyao , Liu Jian , Mu Haoran , Xiao Yao , Mei Bingbao , Liu Wengang , Lin Gang , Jiang Zheng , Wen Liping , Jiang Lei 
Published: October 2019

AbstractThe development of high‐efficiency electrocatalysts for large‐scale water splitting is critical but also challenging. In this study, a hierarchical CoMoSx chalcogel was synthesized on a nickel foam (NF) through an in situ metathesis reaction and demonstrated excellent activity and stability in the electrocatalytic hydrogen evolution reaction and oxygen evolution reaction in alkaline media. The high catalytic activity could be ascribed to the abundant active sites/defects in the amorphous framework and promotion of activity through cobalt doping. Furthermore, the superhydrophilicity and superaerophobicity of micro‐/nanostructured CoMoSx/NF promoted mass transfer by facilitating access of electrolytes and ensuring fast release of gas bubbles. By employing CoMoSx/NF as bifunctional electrocatalysts, the overall water splitting device delivered a current density of 500 mA cm−2 at a low voltage of 1.89 V and maintained its activity without decay for 100 h.
Synergistic N‐Heterocyclic Carbene/Palladium‐Catalyzed Umpolung 1,4‐Addition of Aryl Iodides to Enals
Authors: Yang Wenjun , Ling Bo , Hu Bowen , Yin Haolin , Mao Jianyou , Walsh Patrick J. 
Published: October 2019

AbstractAn umpolung 1,4‐addition of aryl iodides to enals promoted by cooperative (terpy)Pd/NHC catalysis was developed that generates various bioactive β,β‐diaryl propanoate derivatives. This system is not only the first reported palladium‐catalyzed arylation of NHC‐bound homoenolates but also expands the scope of NHC‐induced umpolung transformations. A diverse array of functional groups such as esters, nitriles, alcohols, and heterocycles are tolerated under the mild conditions. This method also circumvents the use of moisture‐sensitive organometallic reagents.
Structural Evolution of Water on ZnO(100): From Isolated Monomers via Anisotropic H‐Bonded 2D and 3D Structures to Isotropic Multilayers
Authors: Yu Xiaojuan , Schwarz Paul , Nefedov Alexei , Meyer Bernd , Wang Yuemin , Wöll Christof 
Published: October 2019

AbstractThe surface chemistry of water on zinc oxides is an important topic in catalysis and photocatalysis. Interaction of D2O with anisotropic ZnO(10
0) surfaces was studied by IR reflection absorption spectroscopy using s‐ and p‐polarized light incident along different directions. Interpretation of the experimental data is aided using isotopologues and DFT calculations. The presence of numerous species is revealed: intact monomers, a mixed 2D D2O/OD adlayer, an anisotropic bilayer, and H‐bonded 3D structures. The isolated water monomers are identified unambiguously at low temperatures. The thermally induced diffusion of water monomers occurs at elevated temperatures, forming dimers that undergo autocatalytic dissociation via proton transfer. Polarization‐ and azimuth‐resolved IR data provide information on the orientation and strength of H‐bonds within the 2D and 3D structures. Ab initio molecular dynamics simulations reveal strong anharmonic couplings within the H‐bond network.
Amorphous Ionic Polymers with Color‐Tunable Ultralong Organic Phosphorescence
Authors: Wang He , Shi Huifang , Ye Wenpeng , Yao Xiaokang , Wang Qian , Dong Chaomin , Jia Wenyong , Ma Huili , Cai Suzhi , Huang Kaiwei , Fu Lishun , Zhang Yanyun , Zhi Jiahuan , Gu Long , Zhao Yanli , An Zhongfu , Huang Wei 
Published: October 2019

AbstractAmorphous purely organic phosphorescence materials with long‐lived and color‐tunable emission are rare. Herein, we report a concise chemical ionization strategy to endow conventional poly(4‐vinylpyridine) (PVP) derivatives with ultralong organic phosphorescence (UOP) under ambient conditions. After the ionization of 1,4‐butanesultone, the resulting PVP‐S phosphor showed a UOP lifetime of 578.36 ms, which is 525 times longer than that of PVP polymer itself. Remarkably, multicolor UOP emission ranging from blue to red was observed with variation of the excitation wavelength, which has rarely been reported for organic luminescent materials. This finding not only provides a guideline for developing amorphous polymers with UOP properties, but also extends the scope of room‐temperature phosphorescence (RTP) materials for practical applications in photoelectric fields.
A Light‐up Logic Platform for Selective Recognition of Parallel G‐Quadruplex Structures via Disaggregation‐Induced Emission
Authors: Deiana Marco , Chand Karam , Jamroskovic Jan , Obi Ikenna , Chorell Erik , Sabouri Nasim 
Published: October 2019

AbstractThe design of turn‐on dyes with optical signals sensitive to the formation of supramolecular structures provides fascinating and underexplored opportunities for G‐quadruplex (G4) DNA detection and characterization. Here, we show a new switching mechanism that relies on the recognition‐driven disaggregation (on‐signal) of an ultrabright coumarin‐quinazoline conjugate. The synthesized probe selectively lights‐up parallel G4 DNA structures via the disassembly of its supramolecular state, demonstrating outputs that are easily integrable into a label‐free molecular logic system. Finally, our molecule preferentially stains the G4‐rich nucleoli of cancer cells.
High‐performance PA1/TPU films with enhanced dielectric constant and low loss tangent
Authors: Yuan Dandan , Chen Minzhang , Xu Yuanting , Huang Lei , Ma Jun , Peng Qinghai , Cai Xufu 
Published: October 2019

ABSTRACTPolymer composites with high dielectric constant are promising materials for energy‐storage application. However, their development has generally been hindered due to the challenge to balance dielectric constant and loss tangent. In this work, a novel thermoplastic polyurethane (TPU)‐based composite with high dielectric constant and low loss tangent was prepared by inducing polyamide‐1(PA1). The optimal content of PA1 in TPU matrix was 1.0 wt %. Importantly, the dielectric constant of TPU exhibited great stability at the frequency range of 103–106 Hz and increased sharply with the addition of PA1. In specific, the dielectric constant of TPU increased from 8 to 41 with the incorporation of 1.0 wt % PA1, which was five times higher than that of pure TPU. Meanwhile, the loss tangent still kept at a low level of less than 0.02. This work may provide a new direction for preparation of dielectric polymer composites with excellent comprehensive performance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48469.
Preparation of hydrophilic woven fabrics: Surface modification of poly(ethylene terephthalate) by grafting of poly(vinyl alcohol) and poly(vinyl alcohol)‐g‐(N‐vinyl‐2‐pyrrolidone)
Authors: Erdoğan Meryem Kalkan , Akdemir Özgür , Hamitbeyli Agamirza , Karakışla Meral 
Published: October 2019

ABSTRACTOne of the most industrially important synthetic textile materials, woven poly(ethylene terephthalate) (PET) fabrics, have limitations in the usage of casual apparel applications due to their unwanted hydrophobicity. For that reason, in this study, to impart permanent hydrophilicity to the PET fabrics, hydrophilic poly(vinyl alcohol) (PVA) and a PVA‐based copolymer were introduced to the alkaline hydrolysis pretreated PET surface by graft copolymerization for the first time. The graft modification of PET fabric surface was performed with an industrial‐adaptable approach. The synthesis of a novel PVA‐g‐(N‐vinyl‐2‐pyrrolidone) copolymer was achieved by the introduction of glycidyl methacrylate monomer to the PVA backbone. The structure of the copolymer was evidenced by attenuated total reflection–Fourier transform infrared spectroscopy and 1H‐NMR techniques. The introduction of PVA and copolymer structures with desired functional groups to the PET fabric surface was confirmed with the X‐ray photoelectron spectroscopy technique. It was obtained that the contact angle–wetting time of PET fabric (145° and 98 s) could be dropped to 37° and 0.1 s and 64° and 0.7 s after PVA and copolymer grafting, respectively. This suggests that the graft‐modified PET fabrics may find the potential of use in the textile applications as the alternative hydrophilic materials. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48584.
Improved hydrothermal aging performance of glass fiber‐reinforced polymer composites via silica nanoparticle coating
Authors: Zhang Yongchao , Mi Changwen 
Published: October 2019

ABSTRACTThe long‐term exposure to a hot and humid environment severely damages the bonding integrity of fiber‐reinforced polymer composites and thus significantly degrades their mechanical performances. In this work, we aim to develop an improvement procedure for effectively enhancing the bonding strength in glass fiber‐reinforced polymers (GFRPs). Glass fibers were coated with a thin layer of silica nanoparticles of different concentrations by the use of the evaporative deposition method. Micromorphological comparisons in terms of scanning electron microscope imaging demonstrate significant improvements on the surface roughness of glass fibers. With the coated glass fibers, GFRP composite laminates were designed, molded through the vacuum‐assisted resin infusion technique, and experimentally tested for quantitatively studying their hydrothermal aging performance. The water absorption tests conducted for three exposure temperatures suggest that both the water diffusion rate and the equilibrium water content can be effectively reduced due to the introduction of the silica coating. With increased exposure temperatures, however, the desired reductions become much less significant. A so‐called water‐channel diffusion mechanism along fiber/resin interfaces was proposed to explain the coupling effects of silica coating and exposure temperature. Reductions of water diffusion rate and equilibrium water content were expected to slow down the hydrothermal aging performance of GFRPs. For this purpose, both uniaxial tensile test and three‐point bending test were subsequently performed on GFRP specimens that have been subjected to different coating concentrations, exposure temperatures, and exposure durations. When compared with untreated GFRP specimens, both experiments demonstrate that the residual strength and stiffness can be effectively promoted through coating a thin layer of silica nanoparticles on glass fiber surfaces. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,137, 48652.