bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust, Superelastic Hard Carbon with In Situ Ultrafine Crystals
Authors: Ding Chenfeng , Huang Lingbo , Yan Xiaodong , Dunne Francis , Hong Song , Lan Jinle , Yu Yunhua , Zhong Wei‐Hong , Yang Xiaoping 
Published: October 2019

AbstractAdvancement in developing superelastic carbon aerogels is highly demanded in new industry sectors, particularly in wearable functional electronics for artificial intelligence applications. However, it is very challenging to increase the compressive strength and electrical conductivity while lowering the density of carbon aerogels. Here, an ultralight and superelastic hard carbon aerogel with in situ ultrafine carbon crystals is reported. Based on a novel precursor prepared from self‐assembling bacterial cellulose and thiourea molecules, the resulting aerogel possesses a unique cellular structure and simultaneously exhibits remarkable compressive and electrical properties with ultralow density in addition to excellent compressive cyclability. Specifically, the normalized compression strength and electrical conductivity are up to 20 and 10 times, respectively, of reported carbon aerogels. Armed with the compressed aerogel electrodes, the supercapacitor exhibits excellent electrochemical performance in areal capacitance, rate capability, and high‐power cyclic stability. Furthermore, the supercapacitor displays distinguished pressure‐response capacitive signal and excellent signal cyclicality. This study provides a unique carbon aerogel for advanced wearable monitoring and energy storage systems.
Dynamically Reconfigurable, Multifunctional Emulsions with Controllable Structure and Movement
Authors: Ku Kang Hee , Li Jie , Yoshinaga Kosuke , Swager Timothy M. 
Published: October 2019

AbstractDynamically reconfigurable oil‐in‐water (o/w) Pickering emulsions are developed, wherein the assembly of particles (i.e., platinum‐on‐carbon and iron‐on‐carbon particles) can be actively controlled by adjusting interfacial tensions. A balanced adsorption of particles and surfactants at the o/w interface allows for the creation of inhomogeneity of the particle distribution on the emulsion surface. Complex Pickering emulsions with highly controllable and reconfigurable morphologies are produced in a single step by exploiting the temperature‐sensitive miscibility of hydrocarbon and fluorocarbon liquids. Dynamic adsorption/desorption of (polymer) surfactants afford both shape and configuration transitions of multiple Pickering emulsions and encapsulated core/shell structured can be transformed into a Janus configuration. Finally, to demonstrate the intrinsic catalytic or magnetic properties of the particles provided by carbon bound Pt and Fe nanoparticles, two different systems are investigated. Specifically, the creation of a bimetallic microcapsule with controlled payload release and precise modulation of translational and rotational motions of magnetic emulsions are demonstrated, suggesting potential applications for sensing and smart payload delivery.
A Bendable, Stretchable Transistor with Aligned Carbon Nanotube Films
Authors: Yu Ilhwan , Ye Youngsin , Moon Sangji , Lee Seoung‐Ki , Joo Yongho 
Published: October 2019

AbstractControlling the packing density and degree of alignment of carbon nanotubes is essential for obtaining optimal charge transport properties in carbon nanotube transistors. Here, a method is introduced for evaporative self‐assembly at the air–water interface to deposit continuous films of well‐aligned, uniform semiconducting bundle nanotubes for stretchable and bendable transistor applications. Polymer‐wrapped nanotubes in organic ink are dropped on the water surface and diffused at the air–water interface to deposit aligned semiconducting single‐walled carbon nanotubes on a partially submersed substrate. The speed dependency of the substrate is also elucidated. The optimized conditions enable alignment within ±5° at a packing density of ≈12.5 nanotubes µm−1 with continuously well‐ordered layers. The semiconducting single‐walled carbon nanotube films enabled a high degree of stretchability, with the flexible nature of the ion gel maintaining the charge properties of the device. The resulting ion‐gel‐based field effect transistor devices have a high mobility of 5.11 cm2 V−1 s−1 and an on/off ratio >104 under both bending and elongation and demonstrate a continuous performance over 1000 stretching cycles.
Geomaterial‐Functionalized Microfluidic Devices Using a Universal Surface Modification Approach
Authors: Zhang Yaqi , Yesiloz Gurkan , Sharahi Hossein Jiryaei , Khorshidian Hossein , Kim Seonghwan , Sanati‐Nezhad Amir , Hejazi Seyed Hossein 
Published: October 2019

AbstractThe layer‐by‐layer (LbL) self‐assembly technique is used to coat the surface of flow channels in microfluidic chips with geomaterials. The surface modifications diminish the discrepancy between the surface chemistry of synthesized microfluidic devices and those of underground porous rocks. Hence, the use of visual models and, in particular, microfluidic devices is broadened to simulate the multiphase flows and fluid–solid interactions in actual rocks. Glass and quartz substrates are successfully coated with silicon dioxide (SiO2), bentonite, and montmorillonite. On‐chip functionalization of polydimethylsiloxane (PDMS) and glass micromodels with SiO2 is also accomplished. The functionalized coatings using confocal laser scanning microscopy (CLSM), atomic force microscopy (AFM), and contact angle measurements are characterized. The surface modification technique is shown to be material‐independent, which generates a hydrophilic surface. The surface‐coated chips, functionalized by clay particles, are utilized to illustrate the role of water salinity on oil displacement.
Effect of Dielectric Environment on Excitonic Dynamics in Monolayer WS2
Authors: Fu Yang , He Dawei , He Jiaqi , Bian Ang , Zhang Lu , Liu Shuangyan , Wang Yongsheng , Zhao Hui 
Published: October 2019

AbstractAn experimental study on the effect of hexagonal boron nitride (h‐BN) underlay and cap layers on excitonic dynamics in monolayer WS2 is reported. A monolayer WS2 flake is fabricated by mechanical exfoliation. By using a dry transfer technique, three regions of the sample are obtained: WS2 directly on SiO2, WS2 on h‐BN, and WS2 sandwiched by two h‐BN flakes. Photoluminescence measurements show higher yield and narrower linewidth of the h‐BN/WS2/h‐BN region. Transient absorption measurements reveal that the top h‐BN layer enhances the exciton formation, prolongs the exciton lifetime, and slightly affects the exciton–exciton annihilation. By performing spatially resolved transient absorption measurements, exciton diffusion coefficients of about 100, 40, and 26 cm2 s−1 for the regions of WS2, h‐BN/WS2, and h‐BN/WS2/h‐BN, respectively, are obtained. The suppression of exciton diffusion by h‐BN is attributed to the additional phonon scattering mechanisms introduced by h‐BN, which decreases the exciton mean free path and thus the diffusion coefficient. The findings provide useful information for designing and understanding the effect of h‐BN layers interfacing with 2D semiconductors.
Fabrication of a MoS2/Graphene Nanoribbon Heterojunction Network for Improved Thermoelectric Properties
Authors: Oh Jinwoo , Kim Youngwoo , Chung Seungjun , Kim Heesuk , Son Jeong Gon 
Published: October 2019

AbstractA number of 2D materials have been developed that have properties different from bulk materials due to the quantum confinement effect. These 2D materials can also form a vertical van der Waals heterojunction at a large interface with other 2D materials, resulting in unique electronic and thermoelectric properties. However, it is difficult to fabricate a van der Waals heterostructure of 2D materials that can provide a sufficient temperature gradient while also forming carrier paths across the vertical heterojunction. Here, a heterojunction network structure constructed of highly conductive sub‐20‐nm graphene nanoribbons (GNRs) arrays stacked on a semiconducting molybdenum disulfide (MoS2) monolayer is suggested to maximize the heterojunction effect on carrier transport. This heterojunction network allows the carriers inevitably pass back and forth between the GNR and the MoS2 through the vertical heterojunction, effectively utilizing the interfacial properties in thermoelectricity. This structure also can modify the band structure by controlling the linewidth of the nanoribbons, or introduce an interlayer at the heterojunctions to enhance the tunneling effect between the two layers, thus significantly improved thermoelectric properties are achieved such as enhanced electrical conductivity of 700 S m−1 and a high power factor of 222 µW m−1 K−1.
Self‐Sealed Polyamide (PA)/Zinc Imidazole Framework (ZIF) Thin Film Nanocomposite (TFN) Nanofiltration Membranes with Nanoscale Turing Type Structures
Authors: Yang Wenjie , Zhu Yaoyao , Sun Zhijuan , Gao Congjie , Xue Lixin 
Published: October 2019

AbstractPolyamide (PA) thin‐film composite (TFC) nanofiltration (NF) membranes with superior water permeating nanoscale Turing type networks are formed using preloaded zinc(II) cations as diffusion slower during the interfacial polymerization on polysulfone support. Large nanopores in the size of about 4.3–8.0 Å formed during the interfacial polymerization process are self‐sealed by in situ grown zinc imidazole framework (ZIF) nanocrystals in a counterdiffusion polymerization reaction of Zn(II) cations with imidazole ligands. PA/ZIF mixed matrix NF membranes with superior water permeating networks are formed. Such novel membranes show not only 3–4 fold higher water flux than TFC membranes, but also retain comparably high salt rejection and antifouling resistance capability. The impact of Zn(II) loading levels, counterdiffusion reaction times, and structures of imidazole ligands on the structures and properties of formed TFN‐ZIF membranes are studied.
Insect Solutions for Open Self‐Cleaning Microfluidics
Authors: Zhang Chengqi , Adler Peter H. , Kornev Konstantin G. 
Published: October 2019

AbstractInsect feeding devices with unobstructed channels offer a wetting–dewetting dichotomy that allows fluid to be self‐contained but the channels to be self‐cleaning. An explanation of this unprecedented robustness is previously lacking. C‐faced channels are fabricated with different openings and their surfaces are modified to study the effects of different contact angles on channel wettability. X‐ray microcomputed tomography (micro‐CT) reveals hidden features of wetting–dewetting transitions of droplets in these channels. A wetting–dewetting phase diagram is theoretically constructed and experimentally validated to reveal the conditions for which a liquid will spread to form a column that is self‐contained in these channels. This study significantly relaxes the requirements for materials to be wettable and self‐contain fluids. This work offers promising new applications for microfluidics that can keep the empty channels clean but allow efficient transport of probing liquids.
Palladium‐Catalyzed Cascade Reductive and Carbonylative Cyclization of Ortho‐Iodo‐Tethered Methylenecyclopropanes (MCPs) Using N‐Formylsaccharin as CO Source
Authors: Fan Xing , Shi Min , Wei Yin 
Published: October 2019

AbstractA palladium‐catalyzed reductive and carbonylative cyclization of ortho‐iodo‐tethered methylenecyclopropanes (MCPs) using N‐formylsaccharin as CO source has been developed, affording the desired indanone derivatives in moderate to good yields with high regio‐ and stereoselectivity and good functional group compatibility.magnified image
Synthesis of Indenones via Palladium‐Catalyzed Ligand‐Free Carbonylation
Authors: Song Juan , Sun Haisen , Sun Wei , Fan Yuxuan , Li Cui , Wang Haotian , Xiao Kang , Qian Yan 
Published: October 2019

AbstractA palladium‐catalyzed ligand‐free carbonylation reaction has been developed for the synthesis of indenones. Under CO atmosphere, this cascade reaction proceeded smoothly to provide the desired indenones in moderate to excellent yields with good functional‐group compatibility. The mechanistic investigations suggested the in situ formation of palladium nanoparticles and this transformation was driven by a controlled reaction sequence of alkyne insertion followed by carbonylation and annulation to form the indenone framework.magnified image
Mutations in the sonic hedgehog pathway cause macrocephaly‐associated conditions due to crosstalk to the PI3K/AKT/mTOR pathway
Authors: Klein Steven D. , Nguyen Dzung C. , Bhakta Viraj , Wong Derek , Chang Vivian Y. , Davidson Tom B. , Martinez‐Agosto Julian A. 
Published: October 2019

AbstractThe hedgehog (Hh) pathway is highly conserved and required for embryonic patterning and determination. Mutations in the Hh pathway are observed in sporadic tumors as well as under syndromic conditions. Common to these syndromes are the findings of polydactyly/syndactyly and brain overgrowth. The latter is also a finding most commonly observed in the cases of mutations in the PI3K/AKT/mTOR pathway. We have identified novel Hh pathway mutations and structural copy number variations in individuals with somatic overgrowth, macrocephaly, dysmorphic facial features, and developmental delay, which phenotypically closely resemble patients with phosphatase and tensin homolog (PTEN) mutations. We hypothesized that brain overgrowth and phenotypic overlap with syndromic overgrowth syndromes in these cases may be due to crosstalk between the Hh and PI3K/AKT/mTOR pathways. To test this, we modeled disease‐associated variants by generating PTCH1 and Suppressor of Fused (SUFU) heterozygote cell lines using the CRISPR/Cas9 system. These cells demonstrate activation of PI3K signaling and increased phosphorylation of its downstream target p4EBP1 as well as a distinct cellular phenotype. To further investigate the mechanism underlying this crosstalk, we treated human neural stem cells with sonic hedgehog (SHH) ligand and performed transcriptional analysis of components of the mTOR pathway. These studies identified decreased expression of a set of mTOR negative regulators, leading to its activation. We conclude that there is a significant crosstalk between the SHH and PI3K/AKT/mTOR. We propose that this crosstalk is responsible for why mutations in PTCH1 and SUFU lead to macrocephaly phenotypes similar to those observed in PTEN hamartoma and other overgrowth syndromes associated with mutations in PI3K/AKT/mTOR pathway genes.
Visible‐Light‐Induced Remote C−H Difluoroalkylation of 8‐Aminoquinolines via Debrominative Coupling with Functionalized Difluoromethyl Bromides
Authors: Jin Can , Zhu Rui , Sun Bin , Zhang Liang , Zhuang Xiaohui , Yu Chuanming 
Published: October 2019

AbstractAn efficient photocatalytic regioselective difluoroalkylation of 8‐aminoquinolines at the C‐5 position via a debrominative coupling reaction with difluoromethyl bromides has been developed. A series of 8‐aminoquinolines amides proved to be tolerated for this transformation, aﬀording a variety of 5‐difluoromethylated quinoline derivatives in moderate to excellent yields. This protocol was highlighted by its readily available starting materials, wide functional group tolerance, operational simplicity, and mild conditions.
A stable pillared metal–organic framework constructed by H4TCPP ligand as luminescent sensor for selective detection of TNP and Fe3+ ions
Authors: Ye Yu , Sun Libo , Zhang Chenghui , Du Jianfeng , Liu Yuchuan , Song Xiaowei , Liang Zhiqiang 
Published: October 2019

AbstractA novel luminescent metal–organic framework (Zn‐TCPP/BPY) with pillared structure based on 2,3,5,6‐tetrakis(4‐carboxyphenyl)pyrazine (H4TCPP) and 4,4′‐bipyridine (BPY) has been designed and synthesized through a solvothermal reaction. The [Zn2(COO)4] paddlewheel units are linked by TCPP4− ligands to form two‐dimensional layers and further connected by BPY ligands as pillars to construct the twofold interpenetrating three‐dimensional framework. Interestingly, Zn‐TCPP/BPY possesses outstanding stability in organic solvents and water as well as maintains its structural rigidity in aqueous solutions of different pH values (3–12). After activation, Zn‐TCPP/BPY possesses permanent porosity with Brunauer–Emmett–Teller surface area of 630 m2 g–1. Remarkably, Zn‐TCPP/BPY displays excellent fluorescent property in virtue of the aggregation‐induced emission effect of the H4TCPP ligand, which can be highly active and quenched by small amounts of 2,4,6‐trinitrophenol (TNP) and Fe3+ ions. Furthermore, the detection effect of Zn‐TCPP/BPY remains basically the same even after five cycles. The excellent stability, high sensitivity, and recyclability of Zn‐TCPP/BPY make it an outstanding chemical sensor for detecting TNP and Fe3+ ions.
Formaldehyde‐free curing of cotton cellulose fabrics in anhydrous media
Authors: Mommer Stefan , Kurniadi Juliana , Keul Helmut , Möller Martin 
Published: October 2019

ABSTRACTThe effect of formaldehyde‐free curing on standard cotton cellulose fabrics in anhydrous media is studied. Different crosslinkers are applied via (1) a pad‐cure‐dry process (solid/liquid) and (2) in a vapor chamber (solid/gas). The performance of each crosslinker and set of conditions is assessed by measuring dry crease recovery angles, DCRAs. We find that in control samples (treatment without crosslinker) the DCRAs are altered depending on the solvent. Using DMF, carbonyldiimidazole shows the best DCRA (160.1°, 15° higher than the non‐treated fabrics). In ethyl acetate, triglycidyl isocyanurate shows the highest DCRA (22° higher than the control). The most promising crosslinkers are applied with selected catalysts known from literature. Here, trigycidyl isocyanurate in combination with the superbase P4‐t‐Bu gives the best DCRA (35° higher than the control). Using the vapor‐chemical finishing, divinylsulfone as crosslinker increases the DCRA to 162.7° (18° higher than non‐treated fabrics). Hence, cotton cellulose fabrics can be successfully finished in anhydrous conditions. © 2019 The Authors.Journal of Applied Polymer Sciencepublished by Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48371.
Spray processable polyurea formulations: Effect of chain extender length on material properties of polyurea coatings
Authors: Tripathi Manorama , Parthasarathy Surekha , Roy Prasun Kumar 
Published: October 2019

ABSTRACTThe increasing usage of polyurea coatings has attracted the attention of researchers worldwide. Commercial polyurea formulations contain chain extenders as an essential ingredient, which increases the possibility of intermolecular H‐bonding by bringing the urea linkages closer. In this work, we establish the effect of increasing chain length of chain extender on the material properties of the polymer. Different types of chain extender were blended with a long chain diamine and subsequently reacted with an MDI‐based isocyanate prepolymer through a reactive spray processing technique. Polyurea coatings containing aromatic chain extenders were found to exhibit higher tensile strength as compared to their aliphatic analogues. Increasing the chain length of the aliphatic chain extender led to a reduction in the mechanical strength. A suitable combination of aromatic and aliphatic chain extender of short length was found to force the macromolecule to orient in such a fashion so as to result in optimal H‐bonding. This manifested in terms of improved processability, as confirmed by chemorheological investigations. Fourier transform infrared spectroscopy was used to understand the H‐bonded internal structure of the polymer. Optimum H‐bonding resulted in improved mechanical properties of the spray‐coated polyurea. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48573.
Acrylic acid/allyloxy polyethylene glycol copolymer with methoxysilicon end groups as a highly effective dispersant for nano‐SiO2aqueous system
Authors: Yang Bing , Zhou Yu , Chen Hongxiang , Zhang Song , Liu Jingyi 
Published: October 2019

ABSTRACTIn order to improve the dispersity and stability of nano‐SiO2aqueous system with high solid content, acrylic acid/allyloxy polyethylene glycol copolymer dispersants with methoxysilicon end groups (KH590‐AAx‐APEGy) were synthesized by photopolymerization. After adding KH590‐AAx‐APEGyinto the nano‐SiO2aqueous system, the viscosity, the curing time, the particle size, and the zeta potential of these systems were respectively measured. The results showed that introducing polyethylene glycol chain into the dispersant was beneficial to better exerting its electrostatic repulsion and steric hindrance effects and further improving the dispersibility of the nano‐SiO2aqueous system. Moreover, the dispersion stability of SiO2nanoparticles in water was closely related to the composition, the molecular weight, and the addition amount of KH590‐AAx‐APEGyand the solid content. When the molecular weight of KH590‐AAx‐APEGywas 3200 g mol−1and its addition amount was 0.1 wt %, the nano‐SiO2aqueous system with 20 wt % solid content showed the best dispersity and stability. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48617.
Development of novel microsatellite markers for Alkanna tinctoria by comparative transcriptomics
Authors: Ahmad Muhammad , Lazic Desanka , Hansel‐Hohl Karin , Lexer Christian , Sehr Eva Maria 
Published: October 2019

PremiseAlkanna tinctoria (Boraginaceae) is an important medicinal herb with its main distribution across the Mediterranean region. To reveal its genetic variation and population structure, microsatellite markers were developed and validated in four Greek populations.Methods and ResultsRNA‐Seq data of the related species Arnebia euchroma and Echium plantagineum were assembled and mined to identify conserved ortholog sets containing simple sequence repeat motifs. Fifty potential loci were identified and then tested on A. tinctoria, of which 17 loci were polymorphic. The number of alleles ranged from one to nine, and the levels of observed and expected heterozygosity ranged from 0.000 to 1.000 and 0.000 to 0.820, respectively. Most of these loci could be successfully amplified in eight other species of Boraginaceae (Alkanna graeca, A. hellenica, A. sfikasiana, Echium vulgare, E. plantagineum, Lithospermum officinale, Borago officinalis, and Anchusa officinalis).ConclusionsThis study provides the first set of microsatellite loci for studying the genetic variation and population structure of A. tinctoria and shows their potential usefulness in other Boraginaceae species.