bluuebunny/crossref_metadata_2025 huggingface dataset:
Toward High Performance Thiophene‐Containing Conjugated Microporous Polymer Anodes for Lithium‐Ion Batteries through Structure Design
Authors: Zhang Chong , He Yongwu , Mu Pan , Wang Xue , He Qian , Chen Yu , Zeng Jinghui , Wang Feng , Xu Yunhua , Jiang Jia‐Xing
Published: November 2017

Poly(thiophene) as a kind of n‐doped conjugated polymer with reversible redox behavior can be employed as anode material for lithium‐ion batteries (LIBs). However, the low redox activity and poor rate performance for the poly(thiophene)‐based anodes limit its further development. Herein, a structure‐design strategy is reported for thiophene‐containing conjugated microporous polymers (CMPs) with extraordinary electrochemical performance as anode materials in LIBs. The comparative study on the electrochemical performance of the structure‐designed thiophene‐containing CMPs reveals that high redox‐active thiophene content, highly crosslinked porous structure, and improved surface area play significant roles for enhancing electrochemical performances of the resulting CMPs. The all‐thiophene‐based polymer of poly(3,3′‐bithiophene) with crosslinked structure and a high surface area of 696 m2 g−1 exhibits a discharge capacity of as high as 1215 mAh g−1 at 45 mA g−1, excellent rate capability, and outstanding cycling stability with a capacity retention of 663 mAh g−1 at 500 mA g−1 after 1000 cycles. The structure–performance relationships revealed in this work offer a fundamental understanding in the rational design of CMPs anode materials for high performance LIBs.
Hydrogel Encapsulation Facilitates Rapid‐Cooling Cryopreservation of Stem Cell‐Laden Core–Shell Microcapsules as Cell–Biomaterial Constructs
Authors: Zhao Gang , Liu Xiaoli , Zhu Kaixuan , He Xiaoming
Published: November 2017

Core–shell structured stem cell microencapsulation in hydrogel has wide applications in tissue engineering, regenerative medicine, and cell‐based therapies because it offers an ideal immunoisolative microenvironment for cell delivery and 3D culture. Long‐term storage of such microcapsules as cell–biomaterial constructs by cryopreservation is an enabling technology for their wide distribution and ready availability for clinical transplantation. However, most of the existing studies focus on cryopreservation of single cells or cells in microcapsules without a core–shell structure (i.e., hydrogel beads). The goal of this study is to achieve cryopreservation of stem cells encapsulated in core–shell microcapsules as cell–biomaterial constructs or biocomposites. To this end, a capillary microfluidics‐based core–shell alginate hydrogel encapsulation technology is developed to produce porcine adipose‐derived stem cell‐laden microcapsules for vitreous cryopreservation with very low concentration (2 mol L−1) of cell membrane penetrating cryoprotective agents (CPAs) by suppressing ice formation. This may provide a low‐CPA and cost‐effective approach for vitreous cryopreservation of “ready‐to‐use” stem cell–biomaterial constructs, facilitating their off‐the‐shelf availability and widespread applications.
Polyhedral 30‐Faceted BiVO4 Microcrystals Predominantly Enclosed by High‐Index Planes Promoting Photocatalytic Water‐Splitting Activity
Authors: Li Ping , Chen Xingyu , He Huichao , Zhou Xin , Zhou Yong , Zou Zhigang
Published: November 2017

Unprecedented 30‐faceted BiVO4 polyhedra predominantly surrounded by {132}, {321}, and {121} high‐index facets are fabricated through the engineering of high‐index surfaces by a trace amount of Au nanoparticles. The growth of high‐index facets results in a 3–5 fold enhancement of O2 evolution from photocatalytic water splitting by the BiVO4 polyhedron, relative to its low‐index counterparts. Theory calculations reveal that water dissociation is more energetically favorable on the high‐index surfaces than on the low‐index (010), (110), and (101) surfaces, which is accompanied by a notable reduction in the overpotential (0.77–1.14 V) for the oxygen evolution reaction. The apparent quantum efficiency of O2 generation without an external electron supply reaches 18.3% under 430 nm light irradiation, which is an order of magnitude higher than that of the catalysts reported hitherto.
Liquid‐Phase Transmission Electron Microscopy for Studying Colloidal Inorganic Nanoparticles
Authors: Kim Byung Hyo , Yang Jiwoong , Lee Donghoon , Choi Back Kyu , Hyeon Taeghwan , Park Jungwon
Published: November 2017

For the past few decades, nanoparticles of various sizes, shapes, and compositions have been synthesized and utilized in many different applications. However, due to a lack of analytical tools that can characterize structural changes at the nanoscale level, many of their growth and transformation processes are not yet well understood. The recently developed technique of liquid‐phase transmission electron microscopy (TEM) has gained much attention as a new tool to directly observe chemical reactions that occur in solution. Due to its high spatial and temporal resolution, this technique is widely employed to reveal fundamental mechanisms of nanoparticle growth and transformation. Here, the technical developments for liquid‐phase TEM together with their application to the study of solution‐phase nanoparticle chemistry are summarized. Two types of liquid cells that can be used in the high‐vacuum conditions required by TEM are discussed, followed by recent in situ TEM studies of chemical reactions of colloidal nanoparticles. New findings on the growth mechanism, transformation, and motion of nanoparticles are subsequently discussed in detail.
Metal–Organic Frameworks as Platforms for Catalytic Applications
Authors: Jiao Long , Wang Yang , Jiang Hai‐Long , Xu Qiang
Published: November 2017

Metal–organic frameworks (MOFs), also called porous coordination polymers, represent a class of crystalline porous materials built from organic linkers and metal ions/clusters. The unique features of MOFs, including structural diversity and tailorability as well as high surface area, etc., enable them to be a highly versatile platform for potential applications in many fields. Herein, an overview of recent developments achieved in MOF catalysis, including heterogeneous catalysis, photocatalysis, and eletrocatalysis over MOFs and MOF‐based materials, is provided. The active sites involved in the catalysts are particularly emphasized. The challenges, future trends, and prospects associated with MOFs and their related materials for catalysis are also discussed.
Redox Mediators for Li–O2 Batteries: Status and Perspectives
Authors: Park Jin‐Bum , Lee Seon Hwa , Jung Hun‐Gi , Aurbach Doron , Sun Yang‐Kook
Published: November 2017

Li–O2 batteries have received much attention due to their extremely large theoretical energy density. However, the high overpotentials required for charging Li–O2 batteries lower their energy efficiency and degrade the electrolytes and carbon electrodes. This problem is one of the main obstacles in developing practical Li–O2 batteries. To solve this problem, it is important to facilitate the oxidation of Li2O2 upon charging by using effective electrocatalysis. Using solid catalysts is not too effective for oxidizing the electronically isolating Li‐peroxide layers. In turn, for soluble catalysts, red‐ox mediators (RMs) are homogeneously dissolved in the electrolyte solutions and can effectively oxidize all of the Li2O2 precipitated during discharge. RMs can decompose solid Li2O2 species no matter their size, morphology, or thickness and thus dramatically increase energy efficiency. However, some negative side effects, such as the shuttle reactions of RMs and deterioration of the Li‐metal occur. Therefore, it is necessary to study the activity and stability of RMs in Li–O2 batteries in detail. Herein, recent studies related to redox mediators are reviewed and the mechanisms of redox reactions are illustrated. The development opportunities of RMs for this important battery technology are discussed and future directions are suggested.
Ultrathin 2D Photocatalysts: Electronic‐Structure Tailoring, Hybridization, and Applications
Authors: Di Jun , Xiong Jun , Li Huaming , Liu Zheng
Published: November 2017

As a sustainable technology, semiconductor photocatalysis has attracted considerable interest in the past several decades owing to the potential to relieve or resolve energy and environmental‐pollution issues. By virtue of their unique structural and electronic properties, emerging ultrathin 2D materials with appropriate band structure show enormous potential to achieve efficient photocatalytic performance. Here, the state‐of‐the‐art progress on ultrathin 2D photocatalysts is reviewed and a critical appraisal of the classification, controllable synthesis, and formation mechanism of ultrathin 2D photocatalysts is presented. Then, different strategies to tailor the electronic structure of ultrathin 2D photocatalysts are summarized, including component tuning, thickness tuning, doping, and defect engineering. Hybridization with the introduction of a foreign component and maintaining the ultrathin 2D structure is presented to further boost the photocatalytic performance, such as quantum dots/2D materials, single atoms/2D materials, molecular/2D materials, and 2D–2D stacking materials. More importantly, the advancement of versatile photocatalytic applications of ultrathin 2D photocatalysts in the fields of water oxidation, hydrogen evolution, CO2 reduction, nitrogen fixation, organic syntheses, and removal pollutants is discussed. Finally, the future opportunities and challenges regarding ultrathin 2D photocatalysts to bring about new opportunities for future research in the field of photocatalysis are also presented.
Printing Semiconductor–Insulator Polymer Bilayers for High‐Performance Coplanar Field‐Effect Transistors
Authors: Bu Laju , Hu Mengxing , Lu Wanlong , Wang Ziyu , Lu Guanghao
Published: November 2017

Source–semiconductor–drain coplanar transistors with an organic semiconductor layer located within the same plane of source/drain electrodes are attractive for next‐generation electronics, because they could be used to reduce material consumption, minimize parasitic leakage current, avoid cross‐talk among different devices, and simplify the fabrication process of circuits. Here, a one‐step, drop‐casting‐like printing method to realize a coplanar transistor using a model semiconductor/insulator [poly(3‐hexylthiophene) (P3HT)/polystyrene (PS)] blend is developed. By manipulating the solution dewetting dynamics on the metal electrode and SiO2 dielectric, the solution within the channel region is selectively confined, and thus make the top surface of source/drain electrodes completely free of polymers. Subsequently, during solvent evaporation, vertical phase separation between P3HT and PS leads to a semiconductor–insulator bilayer structure, contributing to an improved transistor performance. Moreover, this coplanar transistor with semiconductor–insulator bilayer structure is an ideal system for injecting charges into the insulator via gate‐stress, and the thus‐formed PS electret layer acts as a “nonuniform floating gate” to tune the threshold voltage and effective mobility of the transistors. Effective field‐effect mobility higher than 1 cm2 V−1 s−1 with an on/off ratio > 107 is realized, and the performances are comparable to those of commercial amorphous silicon transistors. This coplanar transistor simplifies the fabrication process of corresponding circuits.
High‐Pressure‐Induced Comminution and Recrystallization of CH3NH3PbBr3 Nanocrystals as Large Thin Nanoplates
Authors: Yin Tingting , Fang Yanan , Chong Wee Kiang , Ming Koh Teck , Jiang Shaojie , Li Xianglin , Kuo Jer‐Lai , Fang Jiye , Sum Tze Chien , White Timothy J. , Yan Jiaxu , Shen Ze Xiang
Published: November 2017

High pressure (HP) can drive the direct sintering of nanoparticle assemblies for Ag/Au, CdSe/PbS nanocrystals (NCs). Instead of direct sintering for the conventional nanocrystals, this study experimentally observes for the first time high‐pressure‐induced comminution and recrystallization of organic–inorganic hybrid perovskite nanocrystals into highly luminescent nanoplates with a shorter carrier lifetime. Such novel pressure response is attributed to the unique structural nature of hybrid perovskites under high pressure: during the drastic cubic–orthorhombic structural transformation at ≈2 GPa, (301) the crystal plane fully occupied by organic molecules possesses a higher surface energy, triggering the comminution of nanocrystals into nanoslices along such crystal plane. Beyond bulk perovskites, in which pressure‐induced modifications on crystal structures and functional properties will disappear after pressure release, the pressure‐formed variants, i.e., large (≈100 nm) and thin (<10 nm) perovskite nanoplates, are retained and these exhibit simultaneous photoluminescence emission enhancing (a 15‐fold enhancement in the photoluminescence) and carrier lifetime shortening (from ≈18.3 ± 0.8 to ≈7.6 ± 0.5 ns) after releasing of pressure from 11 GPa. This pressure‐induced comminution of hybrid perovskite NCs and a subsequent amorphization–recrystallization treatment offer the possibilities of engineering the advanced hybrid perovskites with specific properties.
Exploration of Chirality and Achirality of Self‐Assembled Monolayer Formed by Unsymmetrically Substituted Fluorenone Derivative at the Liquid/Solid Interface
Authors: Hu Yi , Miao Kai , Dong Meiqiu , Xu Li , Zha Bao , Miao Xinrui , Deng Wenli
Published: November 2017

The self‐assemblies of 2‐decyloxy‐7‐pentadecyloxy‐9‐fluorenone (DPF) are characterized by scanning tunneling microscopy at the liquid/solid interface. Achiral Dimer and chiral S‐like structures are observed in 1‐octanoic acid. The solvent molecule takes part in the self‐assembly via forming COOH⋯OC and COOH⋯COOH hydrogen bonds. When 1‐phenyloctane and n‐tetradecane are used as the solvents, DPF self‐assembles into chiral Z‐like structure, which are classified into Types I–IV according to the packing styles. For the purpose of exploring the effect of solvent and the competition between these three structures, the self‐assemblies of DPF in mixed solvents and on dry surface are investigated. The results show that S‐like structure is preferred in mixed solvents, while the Z‐like structure has priority when the function of solvent is excluded. DPF molecule shows polarity thus dipole−dipole interaction plays significant roles on forming stable adlayers by forming antiparallel dipole pairs. Furthermore, density functional theory calculation is performed to reveal the driving forces of hydrogen bonds and van der Waals interactions. In light of the popularity of studying chirality at the liquid/solid interface, it is believed that the findings will provide implications for designing chiral systems and will promote the exploration of self‐assembly in the field of surface science.
Graphene Oxide Epoxy (GO‐xy): GO as Epoxy Adhesive by Interfacial Reaction of Functionalities
Authors: Vinod Soumya , Tiwary Chandra Sekhar , Samanta Atanu , Ozden Sehmus , Narayanan Tharangattu N. , Vajtai Robert , Agarwal Vipin , Singh Abhishek K. , John George , Ajayan Pulickel M.
Published: November 2017

The unique combination of layered structure and chemical moieties grants very interesting physiochemical properties to graphene oxide (GO). Functional groups such as epoxide, hydroxyl, and carboxyl are abundantly distributed along the hexagonal lattice of carbon atoms. The superior properties of GO and increased interfacial interaction with other compounds make them excellent filler materials in polymers such as epoxies for creating multifunctional composites. Alternatively, the presence of epoxide group on GO opens up the possibility of using it as the major epoxy matrix constituent rather than just as a filler material. In this work, the formation of GO‐xy (cross‐linked GO via the epoxide functionality) resin is reported by reaction of GO with polymercaptan‐based hardener by completely eliminating the need for conventional epoxy component. Substituting epoxy with GO marks notable advance in preparing adhesive materials with high temperature stability.
A Hybrid Piezoelectric and Triboelectric Nanogenerator with PVDF Nanoparticles and Leaf‐Shaped Microstructure PTFE Film for Scavenging Mechanical Energy
Authors: Zhu Jianxiong , Zhu Yali , Wang Xiaohu
Published: November 2017

In this paper, a hybrid of piezoelectric polyvinylidene fluoride (PVDF)/polytetrafluoroethylene (PTFE) compound film and triboelectric leaf‐shaped microstructure film for mechanical energy harvesting is first reported. The nanoparticles compound film is designed with PVDF particles and leaf‐shaped PTFE. The triboelectric nanogenerator (TENG) is positioned at the upper side of the prototype and the piezoelectric nanogenerator (PENG) is placed at the lower side. It is found that the designed PENG could greatly enhance the harvested power by a coupling effect of PVDF nanoparticles and the compound PVDF/PTFE film than commercial film, and the leaf‐shaped PTFE film could benefit the electric output for the TENG. The average output power density of TENG and PENG can achieve 2.75 and 0.15 mW m−2 with resistor 300 MΩ, respectively. It is found that with the increasing external accelerations on prototype, the maximum generated output voltage by this mechanic‐electric conversion could obtain around 55 and −5.6 V by the two peak values, respectively. In the end, a random test using finger tap to light eight light‐emitting diodes is demonstrated the mechanical energy conversion performance of the TENG and PENG with the generated peak voltage of TENG and PENG 25 and −5.2 V, respectively.
Effect of UV Irradiation and Heat Treatment on the Surface Potential Distribution of Monolayer WS2 on SiO2/Si and Au Substrates
Authors: Han Weipeng , Qi Junjie , Li Feng , Xu Minxuan , Bai Fan , Fang Youyin , Liu Xinxin , Zhang Yue
Published: November 2017

The surface potential is relevant to work function and Fermi level of materials, which is of great significance to the research of charge transport, carrier concentration, and nanodevices design. Here the effect of UV illumination and heat treatment on the surface potential distribution of chemical vapor deposition grown monolayer WS2 on SiO2/Si and Au substrates is studied statistically. The experimental observation indicates that with the increase in light intensity, the surface potential of WS2 decreases on SiO2/Si substrate, while increases on Au substrate. Heat treatment is introduced to tuning the surface potential of monolayer WS2, resulting in the surface potential of WS2 on SiO2/Si substrate decrease and increase on Au substrate after annealing, respectively. The mechanism of the observed phenomenon is discussed in terms of the surface modification of the adsorption/desorption of charges on surface, photoinduced carriers, and charge transfer. This study provides a significant insight into the surface properties and can help optimize the performance of electronic and photonic devices.
Hydrogenation of Carbonyl Derivatives Catalysed by Manganese Complexes Bearing Bidentate Pyridinyl‐Phosphine Ligands
Authors: Wei Duo , Bruneau‐Voisine Antoine , Chauvin Téo , Dorcet Vincent , Roisnel Thierry , Valyaev Dmitry A. , Lugan Noël , Sortais Jean‐Baptiste
Published: November 2017

Manganese(I) catalysts incorporating readily available bidentate 2‐aminopyridinyl‐phosphine ligands achieve a high efficiency in the hydrogenation of carbonyl compounds, significantly better than parent ones based on more elaborated and expensive tridentate 2,6‐(diaminopyridinyl)‐diphosphine ligands. The reaction proceeds with low catalyst loading (0.5 mol%) under mild conditions (50 °C) with yields up to 96%.

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Ruthenium(II)‐Catalyzed C−H Chalcogenation of Anilides
Authors: Ma Wenbo , Weng Zhengyun , Rogge Torben , Gu Linghui , Lin Jiafu , Peng Ai , Luo Xiang , Gou Xiaojun , Ackermann Lutz
Published: November 2017

Ruthenium‐catalyzed C−H chalcogenations of anilides with readily available diselenides and disulfides have been achieved. Our strategy features ample substrate scope, affording the mono‐ortho selenylated and thiolated anilides with complete site selectivity control and high catalytic efficacy. Detailed mechanistic studies provide strong support for a facile base‐assisted internal electrophilic substitution (BIES) metalation event.

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Ligand‐free Iron(II)‐Catalyzed N‐Alkylation of Hindered Secondary Arylamines with Non‐activated Secondary and Primary Alcohols via a Carbocationic Pathway
Authors: Nayal Onkar S. , Thakur Maheshwar S. , Kumar Manoranjan , Kumar Neeraj , Maurya Sushil K.
Published: November 2017

Secondary benzylic alcohols represent a challenging class of substrates for N‐alkylation of amines. Herein, we describe an iron(II)‐catalyzed eco‐friendly protocol for N‐alkylation of secondary arylamines with secondary benzyl alcohols through a carbocationic pathway instead of the known borrowing hydrogen transfer (BHT) approach. Transiently generated carbocations, produced from alcohols via self‐condensation, were coupled with arylamines to provide highly functionalized amine products. The scope of this methodology involves N‐alkylation of primary, secondary and heterocyclic amines with primary/secondary benzylic, allylic and heterocyclic alcohols, which are common key structures in numerous pharmaceuticals drugs. The method can also be easily adopted for the amination of various natural products.

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Chiral Phosphoric Acid Catalyzed Enantioselective Friedel‐Crafts Reaction of N‐Protected 4‐Aminoindoles with β,γ‐Unsaturated α‐Ketimino Esters
Authors: Ding Yu‐Yang , Xu Deng‐Feng , Meng Shan‐Shui , Li Yang , Zhao Jun‐Ling
Published: November 2017

Through a hydrogen bonding guided substrate modification strategy, we have developed a chiral phosphoric acid catalyzed highly enantioselective Friedel‐Crafts reaction of N‐protected 4‐aminoindoles with β,γ‐unsaturated α‐ketimino esters. The mechanism and origins of the enantioselectivity of this process are indentified using DFT calculations. Both the experimental and calculation results indicated that the NH moiety at the indole C4 position is essential for the stereocontrol of this reaction. To further examine the potential usefulness of this method, gram scale synthesis and derivatizations of one of the products were also carried out.

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Tert‐Butyl Nitrite Mediated Expeditious Methylsulfoxidation of Tetrazole‐amines with DMSO: Metal‐free Synthesis of Antifungal Active Methylsulfinyl‐1H‐tetrazole Derivatives
Authors: Dai Peng , Luo Kai , Yu Xiang , Yang Wen‐Chao , Wu Lei , Zhang Wei‐Hua
Published: November 2017

A tert‐butyl nitrite mediated methyl‐sulfoxidation of tetrazole‐amines in neat DMSO or methyl‐sulfinyl derivatives is revealed for the first time. The reaction exhibits good group tolerance, as well as highly selectivity to sulfinyl substitutions. This new protocol provides an expeditious and operationally simple procedure for C−S(O) bond construction. Preliminary bioactivity evaluation on selected products shows promising antifungal activities.

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Asymmetric Flexible MXene‐Reduced Graphene Oxide Micro‐Supercapacitor
Authors: Couly Cedric , Alhabeb Mohamed , Van Aken Katherine L. , Kurra Narendra , Gomes Luisa , Navarro‐Suárez Adriana M. , Anasori Babak , Alshareef Husam N. , Gogotsi Yury
Published: November 2017

Current microfabrication of micro‐supercapacitors often involves multistep processing and delicate lithography protocols. In this study, simple fabrication of an asymmetric MXene‐based micro‐supercapacitor that is flexible, binder‐free, and current‐collector‐free is reported. The interdigitated device architecture is fabricated using a custom‐made mask and a scalable spray coating technique onto a flexible, transparent substrate. The electrode materials are comprised of titanium carbide MXene (Ti3C2Tx) and reduced graphene oxide (rGO), which are both 2D layered materials that contribute to the fast ion diffusion in the interdigitated electrode architecture. This MXene‐based asymmetric micro‐supercapacitor operates at a 1 V voltage window, while retaining 97% of the initial capacitance after ten thousand cycles, and exhibits an energy density of 8.6 mW h cm−3 at a power density of 0.2 W cm−3. Further, these micro‐supercapacitors show a high level of flexibility during mechanical bending. Utilizing the ability of Ti3C2Tx‐MXene electrodes to operate at negative potentials in aqueous electrolytes, it is shown that using Ti3C2Tx as a negative electrode and rGO as a positive one in asymmetric architectures is a promising strategy for increasing both energy and power densities of micro‐supercapacitors.
The Influence of Solvent Additive on Polymer Solar Cells Employing Fullerene and Non‐Fullerene Acceptors
Authors: Song Xin , Gasparini Nicola , Baran Derya
Published: November 2017

Small‐molecule‐based non‐fullerene acceptors (NFAs) are emerging as a new field in organic photovoltaics, due to their structural versatility, the tunability of their energy levels, and their ease of synthesis. High‐efficiency polymer donors have been tested with these non‐fullerene acceptors in order to further boost the efficiency of organic solar cells. Most of the polymer:fullerene systems are optimized with solvent additives for high efficiency, while little attention has been paid to NFA‐based solar cells so far. In this report, the effect of the most common additive, 1,8‐diiodooctane (DIO), on PTB7‐Th:PC71BM solar cells is investigated and it is compared with non‐fullerene acceptor 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno‐[1,2‐b:5,6b′]di‐thiophene (ITIC) devices. It is interesting that the high boiling solvent additive does have a negative impact on the power conversion efficiency when PTB7‐Th is blended with ITIC acceptor. The solar cell devices are studied in terms of their optical, photophysical, and morphological properties and find out that PTB7‐Th:ITIC devices with DIO results in coarser domains, reduced absorption strength, and slightly lower mobility, while DIO improves the absorption strength of the PTB7‐Th:PC71BM blend film and increase the aggregation of PC71BM in the blend, resulting in higher fill factor and Jsc.
Contract farming and technical efficiency: Evidence from low‐value and high‐value crops in Nepal
Authors: Mishra Ashok K. , Shaik Saleem , Khanal Aditya R. , Bairagi Subir
Published: November 2017

Contract farming (CF), an institutional innovation, can reduce transaction costs and solve market imperfections in many developing countries. This study compares productivity and technical efficiency (TE) of contract and independent producers of high yielding variety (HYV) paddy seed (a low‐value crop) and ginger (a high‐value crop) producers in a sample of smallholders in Nepal. We address the self‐selection into CF by using propensity score matching and translog stochastic frontier function to estimate our empirical model. Using farm‐level data from Nepal, our findings show that CF increased the average TE levels of HYV paddy seed producers from 87% to 94% and the average TE levels of ginger producers from 89% to 97%. Finally, we find that human capital and distance to the market increases the technical inefficiency of low‐value crop smallholders in Nepal. [EconLit citations: C21, O13, Q12].
Outcome of patients with relapsed/refractory acute lymphoblastic leukemia after blinatumomab failure: No change in the level of CD19 expression
Authors: Jabbour Elias , Düll Johannes , Yilmaz Musa , Khoury Joseph D. , Ravandi Farhad , Jain Nitin , Einsele Hermann , Garcia‐Manero Guillermo , Konopleva Marina , Short Nicholas J. , Thompson Philip A. , Wierda William , Daver Naval , Cortes Jorge , O'brien Susan , Kantarjian Hagop , Topp Max S.
Published: November 2017

Blinatumomab, a bi‐specific T‐cell engaging CD3‐CD19 antibody construct, has shown significant activity in patients with relapsed/refractory (R/R) B‐cell acute lymphoblastic leukemia (ALL). Despite this improvement, most patients relapse. Here, we describe the outcome of 68 patients with R/R ALL after failure of blinatumomab therapy: 38 (56%) blinatumomab refractory; 30 (44%) relapsing after initial response. After a median follow‐up of 49 months, 9 (13%) patients remained alive. The median overall survival after blinatumomab failure was 5.2 months. At the time of failure, among 61 patients evaluated for immunophenotype, 56 (92%) had CD19‐positive blasts; only five (8%) had ALL recurrence with CD19‐negative disease. Two patients progressed with lower CD19 expression. In summary, the outcome of patients with R/R ALL after blinatumomab failure is poor and treatment of these patients remains an unmet medical need. Our findings indicate that blinatumomab therapy would not exclude a significant number of patients from the potential benefit of subsequent CD19‐directed therapies such as chimeric antigen receptor T‐cell therapy.
Rare FMR1 gene mutations causing fragile X syndrome: A review
Authors: Sitzmann Adam F. , Hagelstrom Robert T. , Tassone Flora , Hagerman Randi J. , Butler Merlin G.
Published: November 2017

Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, typically due to CGG‐repeat expansions in the FMR1 gene leading to lack of expression. We identified a rare FMR1 gene mutation (c.413G>A), previously reported in a single patient and reviewed the literature for other rare FMR1 mutations. Our patient at 10 years of age presented with the classical findings of FXS including intellectual disability, autism, craniofacial findings, hyperextensibility, fleshy hands, flat feet, unsteady gait, and seizures but without the typical CGG‐repeat expansion. He had more features of FXS than the previously reported patient with the same mutation. Twenty individuals reported previously with rare missense or nonsense mutations or other coding disturbances of the FMR1 gene ranged in age from infancy to 50 years; most were verbal with limited speech, had autism and hyperactivity, and all had intellectual disability. Four of the 20 individuals had a mutation within exon 15, three within exon 5, and two within exon 2. The FMR1 missense mutation (c.413G>A) is the same as in a previously reported male where it was shown that there was preservation of the post‐synaptic function of the fragile X mental retardation protein (FMRP), the encoded protein of the FMR1 gene was preserved. Both patients with this missense mutation had physical, cognitive, and behavioral features similarly seen in FXS.
Mutation spectra and founder effect of TMC1 in patients with non‐syndromic deafness in Xiamen area, China
Authors: Jiang Yi , Gao Song , Wu Lihua , Jin Xiaohua , Deng Tao , Wang Ligang , Huang Shasha , Gao Xue , Chen Juan , Han Dongyi , Gao Huafang , Dai Pu
Published: November 2017

To analyze the spectrum and founder effect of TMC1 mutations in patients with non‐syndromic deafness in the Xiamen area. Sporadic pedigrees were detected by targeted next‐generation sequencing, and 110 unrelated patients from Xiamen Special Education School were analyzed through Sanger sequencing for the TMC1 gene. In total, 53 SNPs were designed to analyze the haplotypes of the TMC1 c.2050G>C mutation. The probands of three families were found to be homozygous for TMC1 c.2050G>C, and their parents were all heterozygous for the TMC1 c.2050G>C mutation. In 110 unrelated patients from Xiamen Special Education School, four were found to carry compound heterozygotes of TMC1 c.2050G>C, which were compound heterozygotes of c.804G>A, c.1127T>C, c.1165C>T, and c.1396_1398delAAC, respectively. Three types of TMC1 polymorphisms (c.45C>T, c.1713C>T, c.2208+49C>T) and two heterozygotes of novel variants (c.1764‐4C>A, c.2073G>A[p.K691K]) were found in the remaining 100 patients. In total, four novel variants were detected in this study. These mutations and variants were not detected in 100 normal samples. The haplotypes of the probands of families with TMC1 c.2050G>C were identical. There were unique hotspots and spectra of TMC1 mutations in the Xiamen deaf population. Haplotype analysis is useful to understand the founder effect of the hot spot mutation.
Phenotype and genotype analysis of a French cohort of 119 patients with CHARGE syndrome
Authors: Legendre Marine , Abadie Véronique , Attié‐Bitach Tania , Philip Nicole , Busa Tiffany , Bonneau Dominique , Colin Estelle , Dollfus Hélène , Lacombe Didier , Toutain Annick , Blesson Sophie , Julia Sophie , Martin‐Coignard Dominique , Geneviève David , Leheup Bruno , Odent Sylvie , Jouk Pierre‐Simon , Mercier Sandra , Faivre Laurence , Vincent‐Delorme Catherine , Francannet Christine , Naudion Sophie , Mathieu‐Dramard Michèle , Delrue Marie‐Ange , Goldenberg Alice , Héron Delphine , Parent Philippe , Touraine Renaud , Layet Valérie , Sanlaville Damien , Quélin Chloé , Moutton Sébastien , Fradin Mélanie , Jacquette Aurélia , Sigaudy Sabine , Pinson Lucile , Sarda Pierre , Guerrot Anne‐Marie , Rossi Massimiliano , Masurel‐Paulet Alice , El Chehadeh Salima , Piguel Xavier , Rodriguez‐Ballesteros Montserrat , Ragot Stéphanie , Lyonnet Stanislas , Bilan Frédéric , Gilbert‐Dussardier Brigitte
Published: November 2017

CHARGE syndrome (CS) is a genetic disorder whose first description included Coloboma, Heart disease, Atresia of choanae, Retarded growth and development, Genital hypoplasia, and Ear anomalies and deafness, most often caused by a genetic mutation in the CHD7 gene. Two features were then added: semicircular canal anomalies and arhinencephaly/olfactory bulb agenesis, with classification of typical, partial, or atypical forms on the basis of major and minor clinical criteria. The detection rate of a pathogenic variant in the CHD7 gene varies from 67% to 90%. To try to have an overview of this heterogenous clinical condition and specify a genotype–phenotype relation, we conducted a national study of phenotype and genotype in 119 patients with CS. Selected clinical diagnostic criteria were from Verloes (2005), updated by Blake & Prasad (). Besides obtaining a detailed clinical description, when possible, patients underwent a full ophthalmologic examination, audiometry, temporal bone CT scan, gonadotropin analysis, and olfactory‐bulb MRI. All patients underwent CHD7 sequencing and MLPA analysis. We found a pathogenic CHD7 variant in 83% of typical CS cases and 58% of atypical cases. Pathogenic variants in the CHD7 gene were classified by the expected impact on the protein. In all, 90% of patients had a typical form of CS and 10% an atypical form. The most frequent features were deafness/semicircular canal hypoplasia (94%), pituitary defect/hypogonadism (89%), external ear anomalies (87%), square‐shaped face (81%), and arhinencephaly/anosmia (80%). Coloboma (73%), heart defects (65%), and choanal atresia (43%) were less frequent.
Hinweise auf eine Triplett‐Sensibilisierung in der [2+2]‐Photocycloaddition von Eniminiumionen mit sichtbarem Licht
Authors: Hörmann Fabian M. , Chung Tim S. , Rodriguez Elsa , Jakob Matthias , Bach Thorsten
Published: November 2017

Eniminiumionen, die aus den entsprechenden Carbonylverbindungen (Enonen und Enalen) hergestellt wurden, konnten durch Energietransfer in ihren Triplett‐Zustand angeregt werden. Die Intermediate unterzogen sich bei einer Anregungswellenlänge von λ=433 nm oder λ=457 nm in guten Ausbeuten (50–78 %) einer intra‐ oder intermolekularen [2+2]‐Photocycloaddition. Für die Reaktion wurden Iridium‐ oder Rutheniumkatalysatoren (2.5 Mol‐%) mit einer ausreichend hohen Triplett‐Energie verwendet. Ausgehend von einem chiralen sekundären Amin wurde ein Eniminiumion synthetisiert, das mit hoher Enantioselektivität (88 % ee) in einer intermolekularen [2+2]‐Photocycloaddition umgesetzt werden konnte.
Nanoscale Chemical Imaging of Reversible Photoisomerization of an Azobenzene‐Thiol Self‐Assembled Monolayer by Tip‐Enhanced Raman Spectroscopy
Authors: Zheng Li‐Qing , Wang Xing , Shao Feng , Hegner Martin , Zenobi Renato
Published: November 2017

An understanding of the photoisomerization mechanism of molecules bound to a metal surface at the molecular scale is required for designing photoswitches at surfaces. It has remained a challenge to correlate the surface structure and isomerization of photoswitches at ambient conditions. Herein, the photoisomerization of a self‐assembled monolayer of azobenzene‐thiol molecules on a Au surface was investigated using scanning tunneling microscopy and tip‐enhanced Raman spectroscopy. The unique signature of the cis isomer at 1525 cm−1 observed in tip‐enhanced Raman spectra was clearly distinct from the trans isomer. Furthermore, tip‐enhanced Raman images of azobenzene thiols after ultraviolet and blue light irradiation are shown with nanoscale spatial resolution, demonstrating a reversible conformational change. Interestingly, the cis isomers of azobenzene‐thiol molecules were preferentially observed at Au grain edges, which is confirmed by density functional theory.
A General Synthesis of Porous Carbon Nitride Films with Tunable Surface Area and Photophysical Properties
Authors: Peng Guiming , Xing Lidan , Barrio Jesús , Volokh Michael , Shalom Menny
Published: November 2017

Graphitic carbon nitride (g‐CN) has emerged as a promising material for energy‐related applications. However, exploitation of g‐CN in practical devices is still limited owing to difficulties in fabricating g‐CN films with adjustable properties and high surface area. A general and simple pathway is reported to grow highly porous and large‐scale g‐CN films with controllable chemical and photophysical properties on various substrates using the doctor blade technique. The growth of g‐CN films, ascribed to the formation of a supramolecular paste, comprises g‐CN monomers in ethylene glycol, which can be cast on different substrates. The g‐CN composition, porosity, and optical properties can be tuned by the design of the supramolecular paste, which upon calcination results in a continuous porous g‐CN network. The strength of the porous structure is demonstrated by high electrochemically active surface area, excellent dye adsorption and photoelectrochemical and photodegradation properties.
Enhanced antifungal activities of four Zn(II) complexes based on uniconazole
Authors: Ren Guo‐Yu , Li Jie , Zhou Jin‐Hua , Yan Biao , Ren Ying‐Hui , Sun Xiao‐Hong , Ma Hai‐Xia
Published: November 2017

Four Zn(II) complexes, [ZnL2(SO4)]n (1), [ZnL4(H2O)2]•2(NO3)•4EtOH (2), [ZnL2Cl2]•L (3), and [ZnL2Br2]•L (4) (L = uniconazole), were synthesized using a hydrothermal method and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. Complex 1 formed a one‐dimensional polymer chain. However, complexes 2‐4 were obtained as zero‐dimensional mononuclear coordination compounds. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all complexes show better antifungal activities than their ligands and mixtures. In addition, the interactions between the metal salts of complexes 1‐4 and uniconazole seem to be synergistic. Furthermore, the polymer chain structure of complex 1 significantly enhanced the bioactivity, especially against Botryosphaeria ribis (I). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity after the formation of Zn(II) complexes. The resulting data show that the HOMO–LUMO energy gaps of complexes 1‐4 (0.0578, 0.0946, 0.1053, and 0.1245 eV) are smaller than that of the free ligand (0.1247 eV) and correlate with the antifungal activity of the zinc complexes.
Experimental investigation on bubble dynamic behavior in a confined space bioreactor with bacterial suspension
Authors: Guo Cheng‐Long , Tang Qin‐Yuan , Pei Hong‐Shan , Zhang Guo‐Feng , Guo Fei‐Qiang
Published: November 2017

In this work, a confined space bioreactor with bacterial suspension was developed to experimentally investigate the adsorption of microorganisms at the gas–liquid interface and the effects of inner diameter, inclined angle, and gas flow rate on bubble dynamic behavior. The results indicated that the adsorption of microorganisms at the gas–liquid interface was affected by the bacterial chemotaxis and the gas–liquid interface expansion, and the confined space was conducive to accelerate the detachment of smaller bubble and exacerbate the fluctuation of gas–liquid interface. Moreover, the larger inner diameter induced that the bubble was squeezed by the 2 side walls of the confined space bioreactor, restricting the bubble shocking and slowing down the bubble rising velocity for increasing the bubble residence time. Furthermore, the smallest bubble departure size and the shortest inrush time were observed at horizontal capillary orifice, but the largest inrush bubble number was obtained at down‐45° capillary orifice. In addition, the inrush bubble number increased with increasing gas flow rate, but the bubble departure sizes were not much different. The results can be used to optimize the design of aeration system for improving the performance of the bioreactor.
Traditional and innovative protective coatings for outdoor bronze: Application and performance comparison
Authors: Salvadori Barbara , Cagnini Andrea , Galeotti Monica , Porcinai Simone , Goidanich Sara , Vicenzo Antonello , Celi Claudio , Frediani Piero , Rosi Luca , Frediani Marco , Giuntoli Giulia , Brambilla Laura , Beltrami Ruben , Trasatti Stefano
Published: November 2017

A comparative evaluation of traditional and innovative coatings for outdoor bronze surfaces was carried out, including blending or pre‐treatment with non‐toxic corrosion inhibitors on bare and patinated bronze surfaces to simulate both as cast and aged surfaces. Coatings recently applied in bronze conservation practice, commercially available coatings and an innovative end‐capped poly(lactic acid) with a benzotriazole (BTA) moiety have been tested, as well as a triple‐layer system (wax/acrylic polymer/wax). BTA, single‐layer Soter wax, and double layer Incral44/Soter wax were used as a reference. The products were evaluated in terms of aesthetic features, molecular structure, and corrosion protection by means of colorimetric, spectroscopic, and electrochemical tests. All inhibitors showed similar or significantly better results compared to BTA. In particular, sodium oleate and tolyltriazole could be considered as promising lower‐toxicity alternatives to BTA, while the triple‐layer coating applied without pre‐filming inhibitors proved to give a very high protection against corrosion. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46011.
Effect of two different plasticizers on the properties of poly(3‐hydroxybutyrate) binary and ternary blends
Authors: Seoane Irene Teresita , Manfredi Liliana Beatriz , Cyras Viviana Paola
Published: November 2017

Plasticized poly(3‐hydroxybutyrate) (PHB) films were obtained by solvent casting. The effects of two different additives on several properties of PHB have been examined, utilizing tributyrin and poly[di(ethyleneglycol) adipate] (A). Based on changes in the glass transition temperature (Tg) and cold crystallization temperature of host PHB, the two components are miscible with PHB and they can act as plasticizers. Binary and ternary blends were obtained by adding both plasticizers separately or together, respectively. The effect of plasticizer addition on the optical transparency, water vapor permeability, and tensile properties of the films was studied. It was found that the blends remain transparent and water vapor permeability was maintained constant until a 20 wt % of plasticizer content. Plasticizing effect was corroborated and it depended on the plasticizer percentage. Binary blends had an increased plasticity, in concordance with Tg diminution of PHB. Although ternary blends presented Tg diminution, mechanical properties were not improved probaby due to strong interactions between plasticizers. Finally, binary and ternary blends presented enhanced properties, causing an increment on processability. A correct knowledge between the formulation of the film and the role played by each component could allow getting custom films. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46016.
Highly toughened polylactide by renewable Eucommia ulmoides gum
Authors: Kang Hailan , Yao Lei , Li Yushi , Hu Xiaoran , Yang Feng , Fang Qinghong , Zhang Liqun
Published: November 2017

Polylactide (PLA) derived from natural sources has attracted increasing interest and has provided a promising alternative to traditional plastics derived from petroleum sources. With no loss of environmental friendly features, PLA was highly toughened by Eucommia ulmoides gum (EUG) derived from Eucommia ulmoides oliv. The dynamic mechanical analysis, scanning electron microscopy (SEM), and differential scanning calorimetry results show that the PLA–EUG blends were immiscible systems. SEM micrographs revealed that EUG particles were well dispersed in the PLA matrix with number‐average particle diameters of 2–4 μm. The mechanical properties indicated that the tensile strength decreased with increasing EUG contents, but the elongation at break and the impact strength were enhanced. The notched impact strength of the blends improved by 5.9‐fold compared to that of neat PLA. The PLA–EUG blends exhibited distinct shear‐thinning behavior; this indicated good processability, and the storage modulus and loss modulus of the PLA–EUG blends increased with EUG content. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46017.
Mechanical properties of 3D printed polycaprolactone honeycomb structure
Authors: Zhang Pengfei , Arceneaux Donald Joseph , Khattab Ahmed
Published: November 2017

Polycaprolactone is well known as a healing agent material in crack self‐healing applications but not as a structural material. In this study, the focus is on the durability and energy absorption of honeycomb structure made from polycaprolactone through three‐dimensional (3D) printing. The mechanical behavior of honeycomb structures was investigated through in‐plane quasi‐static compression tests at temperatures of 5 °C, room temperature (22 °C), and 40 °C. Energy absorption efficiency and energy absorption capability at different temperatures and in different loading directions was investigated according to the selected stepping upward stress. The “shape recovery” ratio after compression deformation was calculated. The results reveal that the polymeric honeycomb structure has exceptional repeatability under compressive loads. Specimens with relative density 0.20 showed high energy absorption capability, up to 0.988 J cm−3. After the removal of compression loads, specimens recovered up to 80% after the first deformation and up to 70% after the fifth deformation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46018.
Novel imidazole‐grafted hybrid anion exchange membranes based on poly(2,6‐dimethyl‐1,4‐phenylene oxide) for fuel cell applications
Authors: Chen Jiqin , Shen Chunhui , Gao Shanjun , Yuan Yuan , Ren Xuechao
Published: November 2017

Novel organic–inorganic hybrid membranes, based on poly(2,6‐dimethyl‐1,4‐phenylene oxide), have been prepared through 1,2‐dimethylimidazole functional groups and double crosslinking agents including 3‐glycidyloxypropyltrimethoxysilane and tetraethyl orthosilicate by sol–gel process for the purpose of improving the conductivity and alkaline resistance. The structure of membranes was characterized using Fourier‐transform infrared spectra, 1H NMR, and X‐ray diffraction. The physico‐chemical properties of all membranes were shown in ion exchange capacity, water uptake, stability, and conductivity. Membranes with OH– conductivity up to 0.022 at 25 °C and 0.036 S cm−1 at 80 °C. Promisingly, the chemical stability of the resulting membranes remains unchanged after storage in 2 mol dm−3 KOH at 25 °C over at least 10 days. The tensile strength can be higher than 30 MPa, and the elongation at break (Eb) is in the range 6.68–10.84%. Hence, this hybrid membrane can be potentially applied in alkaline fuel cells. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46034.