bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exogenous/Endogenous‐Triggered Mesoporous Silica Cancer Nanomedicine
Authors: Yang Bowen , Chen Yu , Shi Jianlin 
Published: June 2018

AbstractRecent advances in nanomedicine‐based theranostic platforms have catalyzed the generation of new theranostic modalities for pathological abnormalities, such as cancer. Mesoporous silica–based nanomedicines, which feature unique physicochemical properties and specific applicability, are extensively explored for numerous oncological applications. Due to the well‐defined morphology, specific surface area, and pore volume, mesoporous silica nanoparticle (MSN)‐based theranostic platforms have provided unprecedented opportunities for the development of next‐generation cancer nanomedicine. However, current understanding on the underlying mechanisms of how these feasible theranostic platforms interact with exogenous/endogenous triggers and how this unique responsiveness for optimized cancer therapy can be taken advantage of is still preliminary. In this progress report, efforts are made to give a comprehensive overview of the development of MSN‐based “smart” theranostic platforms, from exogenous physical irradiation–triggered platforms for localized therapy to endogenous biological stimulus–triggered platforms for tumor microenvironment responsiveness. It is highly expected that these elaborately fabricated MSN‐based nanoformulations will play an indispensable role in the efficient cancer therapy based on their high therapeutic outcome and reduced side effects.
Ion‐Migration Inhibition by the Cation–π Interaction in Perovskite Materials for Efficient and Stable Perovskite Solar Cells
Authors: Wei Dong , Ma Fusheng , Wang Rui , Dou Shangyi , Cui Peng , Huang Hao , Ji Jun , Jia Endong , Jia Xiaojie , Sajid Sajid , Elseman Ahmed Mourtada , Chu Lihua , Li Yingfeng , Jiang Bing , Qiao Juan , Yuan Yongbo , Li Meicheng 
Published: June 2018

AbstractMigration of ions can lead to photoinduced phase separation, degradation, and current–voltage hysteresis in perovskite solar cells (PSCs), and has become a serious drawback for the organic–inorganic hybrid perovskite materials (OIPs). Here, the inhibition of ion migration is realized by the supramolecular cation–π interaction between aromatic rubrene and organic cations in OIPs. The energy of the cation–π interaction between rubrene and perovskite is found to be as strong as 1.5 eV, which is enough to immobilize the organic cations in OIPs; this will thus will lead to the obvious reduction of defects in perovskite films and outstanding stability in devices. By employing the cation‐immobilized OIPs to fabricate perovskite solar cells (PSCs), a champion efficiency of 20.86% and certified efficiency of 20.80% with negligible hysteresis are acquired. In addition, the long‐term stability of cation‐immobilized PSCs is improved definitely (98% of the initial efficiency after 720 h operation), which is assigned to the inhibition of ionic diffusions in cation‐immobilized OIPs. This cation–π interaction between cations and the supramolecular π system enhances the stability and the performance of PSCs efficiently and would be a potential universal approach to get the more stable perovskite devices.
Lanthanide Contraction as a Design Factor for High‐Performance Half‐Heusler Thermoelectric Materials
Authors: Liu Yintu , Fu Chenguang , Xia Kaiyang , Yu Junjie , Zhao Xinbing , Pan Hongge , Felser Claudia , Zhu Tiejun 
Published: June 2018

AbstractForming solid solutions, as an effective strategy to improve thermoelectric performance, has a dilemma that alloy scattering will reduce both the thermal conductivity and carrier mobility. Here, an intuitive way is proposed to decouple the opposite effects, that is, using lanthanide contraction as a design factor to select alloying atoms with large mass fluctuation but small radius difference from the host atoms. Typical half‐Heusler alloys, n‐type (Zr,Hf)NiSn and p‐type (Nb,Ta)FeSb solid solutions, are taken as paradigms to attest the validity of this design strategy, which exhibit greatly suppressed lattice thermal conductivity and maintained carrier mobility. Furthermore, by considering lanthanide contraction, n‐type (Zr,Hf)CoSb‐based alloys with high zT of ≈1.0 are developed. These results highlight the significance of lanthanide contraction as a design factor in enhancing the thermoelectric performance and reveal the practical potential of (Zr,Hf)CoSb‐based half‐Heusler compounds due to the matched n‐type and p‐type thermoelectric performance.
Atomic Cobalt Covalently Engineered Interlayers for Superior Lithium‐Ion Storage
Authors: Wang Changda , Xie Hui , Chen Shuangming , Ge Binghui , Liu Daobin , Wu Chuanqiang , Xu Wenjie , Chu Wangsheng , Babu Ganguli , Ajayan Pulickel M. , Song Li 
Published: June 2018

AbstractWith the unique‐layered structure, MXenes show potential as electrodes in energy‐storage devices including lithium‐ion (Li+) capacitors and batteries. However, the low Li+‐storage capacity hinders the application of MXenes in place of commercial carbon materials. Here, the vanadium carbide (V2C) MXene with engineered interlayer spacing for desirable storage capacity is demonstrated. The interlayer distance of pristine V2C MXene is controllably tuned to 0.735 nm resulting in improved Li‐ion capacity of 686.7 mA h g−1 at 0.1 A g−1, the best MXene‐based Li+‐storage capacity reported so far. Further, cobalt ions are stably intercalated into the interlayer of V2C MXene to form a new interlayer‐expanded structure via strong V–O–Co bonding. The intercalated V2C MXene electrodes not only exhibit superior capacity up to 1117.3 mA h g−1 at 0.1 A g−1, but also deliver a significantly ultralong cycling stability over 15 000 cycles. These results clearly suggest that MXene materials with an engineered interlayer distance will be a rational route for realizing them as superstable and high‐performance Li+ capacitor electrodes.
Highly Branched VS4 Nanodendrites with 1D Atomic‐Chain Structure as a Promising Cathode Material for Long‐Cycling Magnesium Batteries
Authors: Wang Yanrong , Liu Ziteng , Wang Caixing , Yi Xu , Chen Renpeng , Ma Lianbo , Hu Yi , Zhu Guoyin , Chen Tao , Tie Zuoxiu , Ma Jing , Liu Jie , Jin Zhong 
Published: June 2018

AbstractRechargeable magnesium batteries have attracted increasing attention due to the high theoretical volumetric capacities, dendrite formation‐free characteristic and low cost of Mg metal anodes. However, the development of magnesium batteries is seriously hindered by the lack of capable cathode materials with long cycling life and fast solid‐state diffusion kinetics for highly‐polarized divalent Mg2+ ions. Herein, vanadium tetrasulfide (VS4) with special one‐dimensional atomic‐chain structure is reported to be able to serve as a favorable cathode material for high‐performance magnesium batteries. Through a surfactant‐assisted solution‐phase process, sea‐urchin‐like VS4 nanodendrites are controllably prepared. Benefiting from the chain‐like crystalline structure of VS4, the S22‐ dimers in the VS4 nanodendrites provide abundant sites for Mg2+ insertion. Moreover, the VS4 atomic‐chains bonded by weak van der Waals forces are beneficial to the diffusion kinetics of Mg2+ ions inside the open channels of VS4. Through a series of systematic ex situ characterizations and density functional theory calculations, the magnesiation/demagnesiation mechanism of VS4 are elucidated. The VS4 nanodendrites present remarkable performance for Mg2+ storage among existing cathode materials, exhibiting a remarkable initial discharge capacity of 251 mAh g‐1 at 100 mA g‐1 and an impressive long‐term cyclability at large current density of 500 mA g‐1 (74 mAh g‐1 after 800 cycles).
Functional Film with Electric‐Field‐Aided Aligned Assembly of Quantum Rods for Potential Application in Liquid Crystal Display
Authors: Kaur Sandeep , Murali G. , Manda Ramesh , Chae Young Cheol , Yun Minhee , Lee Joong Hee , Lee Seung Hee 
Published: June 2018

AbstractHarnessing the unique polarized light emission characteristic from semiconductor quantum rods (QRs) necessitates their large‐area unidirectional alignment. Herein, the aligned assembly of CdSe/CdS QRs is demonstrated by fabricating a functional film on a micrometer‐spaced interdigitated electrodes substrate over an area of ≈1.3 cm2. The external electric field is used to control the position and orientation of QRs which is later frozen by the polymerization of reactive mesogen under the exposure of UV light. Under the fluorescence microscope, a judicious change in the QRs emission intensity with the polarizer axis positioned parallel and perpendicular to the alignment direction suggests the optical anisotropy. The degree of alignment of QRs is characterized by the polarization ratio which is measured 0.48 from the photoluminescence spectra. It is found that factors such as optimal QRs concentration and the presence of liquid crystal contributed for better QRs alignment. Such films may be advantageous for liquid crystal display devices to accomplish light polarization and wider color gamut.
Efficient Solar‐Driven Water Oxidation over Perovskite‐Type BaNbO2N Photoanodes Absorbing Visible Light up to 740 nm
Authors: Seo Jeongsuk , Hisatomi Takashi , Nakabayashi Mamiko , Shibata Naoya , Minegishi Tsutomu , Katayama Masao , Domen Kazunari 
Published: June 2018

AbstractPhotoelectrochemical water splitting using semiconductors absorbing a wide range of visible light is a potentially attractive means of harvesting large portions of the solar spectrum. However, this is also very challenging because narrowing the semiconductor band gap lowers the driving force for photoreactions. Herein, a highly active perovskite BaNbO2N exhibiting photoexcitation up to 740 nm for water oxidation is reported. The synthesis route, consisting of moderate nitridation and subsequent annealing in inert Ar flow, enhances the crystallinity of the BaNbO2N surface without inducing the reduction of the Nb species. As a result, a particulate BaNbO2N photoanode exhibits a photocurrent of 5.2 mA cm−2 at 1.23 VRHE under simulated solar irradiation, which is the highest yet reported for an oxynitride responsive at wavelengths above 600 nm. Suppressing the reduction of B‐site cations during the synthesis of perovskite AB(O,N)3, which otherwise results in surface defects or impurities, is critical for achieving high water oxidation activity.
Revising the Concept of Pore Hierarchy for Ionic Transport in Carbon Materials for Supercapacitors
Authors: Borchardt Lars , Leistenschneider Desirée , Haase Jürgen , Dvoyashkin Muslim 
Published: June 2018

AbstractRapid motion of electrolyte ions is a crucial requirement to ensure the fast charging/discharging and the high power densities of supercapacitor devices. This motion is primarily determined by the pore size and connectivity of the used porous carbon electrodes. Here, the diffusion characteristics of each individual electrolyte component, that is, anion, cation, and solvent confined to model carbons with uniform and well‐defined pore sizes are quantified. As a result, the contributions of micropores, mesopores, and hierarchical pore architectures to the overall transport of adsorbed mobile species are rationalized. Unexpectedly, it is observed that the presence of a network of mesopores, in addition to smaller micropores—the concept widely used in heterogeneous catalysis to promote diffusion of sorbates—does not necessarily enhance ionic transport in carbon materials. The observed phenomenon is explained by the stripping off the surrounding solvent shell from the electrolyte ions entering the micropores of the hierarchical material, and the resulting enrichment of solvent molecules preferably in the mesopores. It is believed that the presented findings serve to provide fundamental understanding of the mechanisms of electrolyte diffusion in carbon materials and depict a quantitative platform for the future designing of supercapacitor electrodes on a rational basis.
Highly Efficient Oxygen Reduction Reaction Activity of Graphitic Tube Encapsulating Nitrided CoxFey Alloy
Authors: Sultan Siraj , Tiwari Jitendra N. , Jang Jue‐Hyuk , Harzandi Ahmad M. , Salehnia Foad , Yoo Sung Jong , Kim Kwang S. 
Published: June 2018

AbstractNonprecious metals are promising catalysts to avoid the sluggish oxygen reduction reaction (ORR) in next‐generation regenerative fuel cells or metal–air batteries. Therefore, development of nonprecious metal catalysts for ORR is highly desirable. Herein, precise tuning of the atomic ratio of Fe and Co encapsulated in melamine‐derived nitrogen‐rich graphitic tube (NGT) is reported. The Co1.08Fe3.34 hybrid with metalnitrogen bonds (1: Co1.08Fe3.34@NGT) shows remarkable ORR catalytic activities (80 mV higher in onset potential and 50 mV higher in half‐wave potential than those of state‐of‐the‐art commercial Pt/C catalysts), high current density, and stability. In acidic solution, 1 also shows compatible performance to commercial Pt/C in terms of ORR activity, current density, stability, and methanol tolerance. The high ORR activity is ascribed to the co‐existence of FeN, CoN, and sufficient metallic FeCo alloys which favor faster electron movement and better adsorption of oxygen molecules on the catalyst surface. In the alkaline anion exchange membrane fuel cell setup, this cell delivers the power density of 117 mW cm−2, demonstrating its potential use for energy conversion and storage applications.
Farmers’ preference for bundled input–output markets and implications for adapted dairy hubs in Tanzania—A choice experiment
Authors: Rao Elizaphan J.O. , Mtimet N. , Twine E. , Baltenweck I. , Omore A. 
Published: June 2018

AbstractDairy business hubs (DBHs) are flexible mechanisms for linking farmers to input and output markets. Yet participation by smallholders in these hubs will only be realized if the hub options are adapted to the needs of farmers. We analyze preference for DBHs in Tanzania using survey data from smallholder dairy producers in Tanga and Morogoro. Applying choice experiment method, we find significant preference for hub options with higher milk prices and payment for milk on a fortnight rather than cash basis. Farmers also prefer options that bundle milk marketing with input provision. For bundled inputs, farmers prefer hub options that allow payment for such inputs via credit or check‐off rather than cash. Our analyses also reveal significant heterogeneity in preference among farmers that should be considered in adapting dairy hubs to Tanzania. Emerging dairy hubs in Tanzania should be supported to either establish in‐house input provision arrangements or to enter contracts with agro‐input dealers in their environs. [EconLit citations: C25, C99, Q13]
Price transmission dynamics for quality‐certified food products: A comparison between conventional and organic fluid milk in Italy
Authors: Antonioli Federico , Ben Kaabia Monia , Arfini Filippo , Gil José M. 
Published: June 2018

AbstractDespite the vast number of works investigating price transmission (PT) processes in diverse agrifood markets, very little has been said about quality‐differentiated products. In this paper, we compare the conventional and organic fluid milk sectors in Italy to better understand the economic organization and functioning of one of the most important agrifoods in Italy. Using a unique dataset featuring processor and retail (scanner) prices for the two types of milk, we estimate Momentum‐Threshold Autoregressive models to account for asymmetric price movements in both sectors, but the PT results are eventually symmetric. The Vector Error Correction Model estimations and Impulse Response Functions analysis provide significant insights into the differences between the two markets. [EconLit citations: Q130, Q110, C590]
RhI‐Catalyzed Intramolecular [3+2] Cycloaddition of 1‐Allene‐vinylcyclopropanes
Authors: Liu Cheng‐Hang , Li Feng , Yuan Yuan , Dou Meng , Yu Zhi‐Xiang 
Published: June 2018

AbstractA rhodium‐catalyzed intramolecular [3+2] cycloaddition of 1‐allene‐vinylcyclopropanes (1‐allene‐VCPs) to construct cyclopentane‐embedded bicyclic structures with quaternary stereocenters at the bridgehead position has been developed with good to excellent yields. In addition, this transformation could also be conducted on a large scale with reduced catalyst loading, which could be useful for further derivatizations and applications.
The Existence of Nitrate Radicals in Irradiated TiO2 Aqueous Suspensions in the Presence of Nitrate Ions
Authors: Parrino Francesco , Livraghi Stefano , Giamello Elio , Palmisano Leonardo 
Published: June 2018

AbstractEvidence of the existence of nitrate radical in irradiated aqueous TiO2 suspensions in the presence of nitrate ions are reported for the first time. The joint use of UV/Vis and EPR spectroscopy showed that nitrate radicals are formed by hole induced oxidation of nitrate ions. Photocatalytic degradation of a model alkene compound allowed to highlight the presence of an intermediate organic nitrate deriving from nitrate radical attack to the double bond of the substrate. These results not only allow deeper understanding of photocatalytic processes, but open the route to new green photocatalytic syntheses initiated by nitrate radicals and to new insights in the field of atmospheric chemistry.
Über bisherige Denkweisen hinaus – neue Wirkstoffe zur Überwindung der Antibiotika‐Krise
Authors: Lakemeyer Markus , Zhao Weining , Mandl Franziska A. , Hammann Peter , Sieber Stephan A. 
Published: June 2018

AbstractDie öffentliche Wahrnehmung von Antibiotika als verlässliche Arzneimittel veränderte sich drastisch, als Meldungen über “multiresistente Super‐Erreger” die Nachrichten aufrüttelten. Während die Ursachen für die bakterielle Resistenzentwicklung schnell erkannt wurden, befindet sich die Forschung zur Wiedergewinnung von Antibiotika als effektive Arzneistoffe immer noch am Anfang. Dieser Aufsatz umfasst zahlreiche Aspekte des Entwicklungsprozesses neuer Antibiotika, von der Grundlagenforschung bis zum fertigen Medikament. Er bietet einen interdisziplinären Überblick über Methoden zur Identifizierung neuer Antibiotika und erörtert Strategien, um ihren molekularen Wirkmechanismus aufzuklären. Die Darstellung ausgewählter Antibiotika, die kürzlich mithilfe dieser Plattformen entdeckt wurden, verdeutlicht die Effizienz der Ansätze und hebt vielversprechende klinische Kandidaten mit therapeutischem Potential hervor. Zusätzlich wird das Konzept von Molekülen erörtert, die Krankheitserreger “entwaffnen”, indem sie Schlüsselpunkte der Virulenz adressieren. Der Aufsatz schließt mit einer kritischen Beurteilung jener antibakteriellen Wirkstoffe, die sich derzeit in klinischer Entwicklung befinden. Insgesamt soll dieser Aufsatz ausgewählte, innovative antibakterielle Ansätze verknüpfen, um interdisziplinäre Partnerschaften zwischen Chemikern aus der akademischen und industriellen Forschung anzuregen.
Nonlinear Unmixing of Hyperspectral Datasets for the Study of Painted Works of Art
Authors: Rohani Neda , Pouyet Emeline , Walton Marc , Cossairt Oliver , Katsaggelos Aggelos K. 
Published: June 2018

AbstractNonlinear unmixing of hyperspectral reflectance data is one of the key problems in quantitative imaging of painted works of art. The approach presented is to interrogate a hyperspectral image cube by first decomposing it into a set of reflectance curves representing pure basis pigments and second to estimate the scattering and absorption coefficients of each pigment in a given pixel to produce estimates of the component fractions. This two‐step algorithm uses a deep neural network to qualitatively identify the constituent pigments in any unknown spectrum and, based on the pigment(s) present and Kubelka–Munk theory to estimate the pigment concentration on a per‐pixel basis. Using hyperspectral data acquired on a set of mock‐up paintings and a well‐characterized illuminated folio from the 15th century, the performance of the proposed algorithm is demonstrated for pigment recognition and quantitative estimation of concentration.
Ultrafast Iron‐Catalyzed Reduction of Functionalized Ketones: Highly Enantioselective Synthesis of Halohydrines, Oxaheterocycles, and Aminoalcohols
Authors: Blasius Clemens K. , Vasilenko Vladislav , Gade Lutz H. 
Published: June 2018

AbstractA molecularly defined chiral boxmi iron alkyl complex catalyzes the hydroboration of various functionalized ketones and provides the corresponding chiral halohydrines, oxaheterocycles (oxiranes, oxetanes, tetrahydrofurans, and dioxanes) and amino alcohols with excellent enantioselectivities (up to >99 %ee) and conversion efficiencies at low catalyst loadings (as low as 0.5 mol %). Turnover frequencies of greater than 40000 h−1 at −30 °C highlight the activity of this earth‐abundant metal catalyst which tolerates a large number of functional groups.
A Platinum(II) Complex of Heptamethine Cyanine for Photoenhanced Cytotoxicity and Cellular Imaging in Near‐IR Light
Authors: Mitra Koushambi , Lyons Charles E. , Hartman Matthew C. T. 
Published: June 2018

AbstractControlled generation of cytotoxic agents with near‐IR light is a current focus of photoactivated cancer therapy, including that involving cytotoxic platinum species. A heptamethine cyanine scaffolded PtII complex, IR797‐Platin exhibits unprecedented Pt−O bond scission and enhancement in DNA platination in near‐IR light. This complex also displayed significant singlet oxygen quantum yield thereby qualifying as a near‐IR photodynamic therapeutic agent. The complex showed 30–60 fold enhancement of cytotoxicity in near‐IR light in various cancer cell lines. The cellular imaging properties were also leveraged to observe its significant co‐localization in cytoplasmic organelles. This is the first demonstration of a near‐IR light‐initiated therapy involving the cytotoxic effects of both active cisplatin and singlet oxygen.
Enhanced Cytosolic Delivery and Release of CRISPR/Cas9 by Black Phosphorus Nanosheets for Genome Editing
Authors: Zhou Wenhua , Cui Haodong , Ying Liming , Yu Xue‐Feng 
Published: June 2018

AbstractA biodegradable two‐dimensional (2D) delivery platform based on loading black phosphorus nanosheets (BPs) with Cas9 ribonucleoprotein engineered with three nuclear localization signals (NLSs) at C terminus (Cas9N3) is successfully established. The Cas9N3‐BPs enter cells effectively via membrane penetration and endocytosis pathways, followed by a BPs biodegradation‐associated endosomal escape and cytosolic releases of the loaded Cas9N3 complexes. The Cas9N3‐BPs thus provide efficient genome editing and gene silencing in vitro and in vivo at a relatively low dose as compared with other nanoparticle‐based delivery platforms. This biodegradable 2D delivery platform offers a versatile cytosolic delivery approach for CRISPR/Cas9 ribonucleoprotein and other bioactive macromolecules for biomedical applications.
A Simple, Broad‐Scope Nickel(0) Precatalyst System for the Direct Amination of Allyl Alcohols
Authors: Sweeney Joseph B. , Ball Anthony K. , Lawrence Philippa A. , Sinclair Mackenzie C. , Smith Luke J. 
Published: June 2018

AbstractThe preparation of allylic amines is traditionally accomplished by reactions of amines with reactive electrophiles, such as allylic halides, sulfonates, or oxyphosphonium species; such methods involve hazardous reagents, generate stoichiometric waste streams, and often suffer from side reactions (such as overalkylation). We report here the first broad‐scope nickel‐catalysed direct amination of allyl alcohols: An inexpensive NiII/Zn couple enables the allylation of primary, secondary, and electron‐deficient amines without the need for glove‐box techniques. Under mild conditions, primary and secondary aliphatic amines react smoothly with a range of allyl alcohols, giving secondary and tertiary amines efficiently. This “totally catalytic” method can also be applied to electron‐deficient nitrogen nucleophiles; the practicality of the process was demonstrated in an efficient, gram‐scale preparation of the calcium antagonist drug substance flunarizine (Sibelium®).