bluuebunny/crossref_metadata_2025_split huggingface dataset:
Achieving Over 15% Efficiency in Organic Photovoltaic Cells via Copolymer Design
Authors: Cui Yong , Yao Huifeng , Hong Ling , Zhang Tao , Xu Ye , Xian Kaihu , Gao Bowei , Qin Jinzhao , Zhang Jianqi , Wei Zhixiang , Hou Jianhui 
Published: February 2019

AbstractTernary blending and copolymerization strategies have proven advantageous in boosting the photovoltaic performance of organic solar cells. Here, 15% efficiency solar cells using copolymerization donors are demonstrated, where the electron‐withdrawing unit, ester‐substituted thiophene, is incorporated into a PBDB‐TF polymer to downshift the molecular energy and broaden the absorption. Copolymer‐based solar cells suitable for large‐area devices can be fabricated by a blade‐coating method from a nonhalogen and nonaromatic solvent mixture. Although ternary solar cells can achieve comparable efficiencies, they are not suitable for environment‐friendly processing conditions and show relatively low photostability compared to copolymer‐based devices. These results not only demonstrate high‐efficiency organic photovoltaic cells via copolymerization strategies but also provide important insights into their applications in practical production.
High‐Performance Blue Quantum Dot Light‐Emitting Diodes with Balanced Charge Injection
Authors: Cheng Tai , Wang Fuzhi , Sun Wenda , Wang Zhibin , Zhang Jin , You Baogui , Li Yang , Hayat Tasawar , Alsaed Ahmed , Tan Zhan'ao 
Published: February 2019

AbstractThe balance of hole–electron injection is always a vital factor for the luminance, efficiency and working lifetime of quantum‐dot light‐emitting diodes (QLEDs), especially blue QLEDs. However, currently most approaches proposed to solve this issue involve tedious optimization of device architecture or material composition. Here, high‐performance blue QLEDs are reported based on CdZnS/ZnS quantum‐dot (QDs) by utilizing ZnO nanoparticles (NPs) and Al:Al2O3 as electron‐transporting layer (ETL) and cathode materials, respectively. The effect of post‐annealing temperature on the trap state density in ZnO NPs and the related mechanisms are investigated through optical and photoelectron spectroscopies. The method of controlling ZnO NPs annealing temperature leads to controllable electron‐mobility of ETL, which ultimately optimizes the balance of charge injection. Together with partially oxidized Al cathode (Al:Al2O3), high‐performance blue QLEDs are fabricated with luminance and external quantum efficiency (EQE) up to 27 753 cd m−2 and 8.92%. As far as is known, the peak luminance achieved is the record of deep blue QLEDs. This simple method for regulating charge injection balance via annealing temperature requires no modification of device architecture, making it applicable for a variety of QLEDs structures.
Time to establish pillars in point‐of‐care ultrasound
Authors: Cormack Carolynne J. , Wald Anthony M. , Coombs Peter R. , Kallos Leah , Blecher Gabriel E. 
Published: February 2019

AbstractPoint of care ultrasound (PoCUS) has evolved rapidly and is used by many medical specialties. We propose five essential pillars of PoCUS that are necessary framework for hospital‐based PoCUS training and credentialing programs. The pillars are: governance, infrastructure, administration, education and quality. It is time to establish these pillars to ensure the best practice in PoCUS use.
Practical and Scalable Kinetic Resolution of BINOLs Mediated by a Chiral Counterion
Authors: Jones Benjamin A. , Balan Tudor , Jolliffe John D. , Campbell Craig D. , Smith Martin D. 
Published: February 2019

AbstractBINOLs are valuable and widely used building blocks, chiral ligands, and catalysts that are effective across a remarkable range of different chemical transformations. Here we demonstrate that an ammonium salt catalyzed kinetic resolution of racemic BINOLs with benzyl tosylate proceeds with s up to 46. This is a scalable and practical process that can be applied across >30 different C2‐ and non‐C2‐symmetric BINOLs. Implementation of this method enables the enantioselective synthesis of a wide range of BINOL derivatives with over 99:1 e.r.
A Dual‐Stimuli‐Responsive Coordination Network Featuring Reversible Wide‐Range Luminescence‐Tuning Behavior
Authors: Yao Zhao‐Quan , Xu Jian , Zou Bo , Hu Zhenpeng , Wang Kai , Yuan Yi‐Jia , Chen Ya‐Ping , Feng Rui , Xiong Jian‐Bo , Hao Jialei , Bu Xian‐He 
Published: February 2019

AbstractWe herein report a new coordination network that deforms in a smooth and reversible manner under either thermal or pressure stimulation. Concomitantly, the organic fluorophores coordinatively bound to the channel in a face‐to‐face arrangement respond to this structural deformation by finely adapting their conformation and arrangement. As a result, the material exhibits a remarkable dual‐stimuli‐responsive luminescence shift across almost the entire visible region: The emission color of the crystal gradually changes from cyan to green upon heating and then to red upon pressure compression. Furthermore, each stage exhibits a linear dependence of both the emission maximum and intensity on the stimulus and is fully reversible.
Stereoselectively Assembled Metal–Organic Framework (MOF) Host for Catalytic Synthesis of Carbon Hybrids for Alkaline‐Metal‐Ion Batteries
Authors: Du Min , Song Dian , Huang Aoming , Chen Ruixuan , Jin Danqing , Rui Kun , Zhang Chao , Zhu Jixin , Huang Wei 
Published: February 2019

AbstractCost‐effective metal‐based nanostructured hybrids have been widely dedicated to potential energy storage and conversion applications. Herein, we develop a facile methodology for the synthesis of precise carbon‐confined hybrid nanostructures by stereoselective assembly accompanied by catalytic pyrolysis. Polyacrylonitrile fiber films favors not only metal‐polymer coordination, but also oriented assembly to ensure the well‐defined nanostructure of the carbon hybrids. During chemical vapor deposition (CVD), cobalt‐nanoparticle‐catalyzed growth of carbon‐nanotube branches driven by organic molecules (e.g. melamine) delivers hierarchical carbon hybrids. The resulting carbon hybrids exhibit outstanding electrochemical performance for metal‐ion batteries, for example, a high specific capacity of 680 mAh g−1 after 320 cycles (Li‐storage) and 220 mAh g−1 after 500 cycles (Na‐storage) without decay.
Rapid, Traceless, AgI‐Promoted Macrocyclization of Peptides Possessing an N‐Terminal Thioamide
Authors: Thombare Varsha J. , Hutton Craig A. 
Published: February 2019

AbstractPeptide macrocyclization is often a slow process, plagued by epimerization and cyclodimerization. Herein, we describe a new method for peptide macrocyclization employing the AgI‐promoted transformation of peptide thioamides. The AgI has a dual function: chemoselectively activating the thioamide and tethering the N‐terminal thioamide to the C‐terminal carboxylate. Extrusion of Ag2S generates an isoimide intermediate, which undergoes acyl transfer to generate the native cyclic peptide, resulting in a rapid, traceless macrocylization process. Cyclic peptides are furnished in high yields within 1 hour, free of epimerization and cyclodimerization.
Improved dispersion of the graphene and corrosion resistance of waterborne epoxy–graphene composites by minor cellulose nanowhiskers
Authors: Nie Jing , Liu Dongyan , Li Songtao , Qiu Zhangweijia , Ma Na , Sui Guoxin 
Published: February 2019

ABSTRACTThe uniform dispersion of graphene (GN) in a polymer matrix is still challenging at high loadings. In this study, we introduced a tiny number of cellulose nanowhiskers (CNWs; CNWs/GN = 1:20 w/w) to improve the dispersion of GN nanoplatelets in a waterborne epoxy (WEP) matrix at a GN loading of 1.0 wt %. Compared with that of 1.0% GN–WEP, the Young's modulus of the 1.0% GN–WEP–CNWs was enhanced by about 20.5%. The glass‐transition temperature increased from 70.4°C for 1.0% GN–WEP to 72.8°C for 1.0% GN–WEP–CNWs. The water contact angle of composite film increased by 17°, from about 79° for the film without CNWs to about 96° for the film with CNWs. The anticorrosion efficiency of the coatings was also evaluated with the potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The results reveal the CNW‐containing coating showed better corrosion resistance for mild steel and could be applied as a green dispersant for GN in WEP coatings. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47631.
Fluorescence Turn‐on Synthetic Lipid Rafts on Supramolecular Sheets and Hierarchical Concanavalin A Assembly
Authors: Kim Yongju , Liu Xin , Li Huichang , Lee Myongsoo 
Published: February 2019

AbstractHere we report fluorescence turn‐on synthetic lipid rafts by self‐assembly of a cationic distyrylanthracene derivative on a negatively‐charged sheet in an aqueous solution. First, the negatively‐charged 2D membrane structure is formed by lateral associations of aromatic rods with carboxylate groups. Then, the synthetic rafts are floated on the surface of the negatively‐charged sheets through electrostatic interactions. The fluorescence of the synthetic rafts is turned on due to the aggregation of the positively‐charged AIE dye on the sheets, facilitating monitoring of the formation of rafts. Concanavalin A (Con A) protein can load hierarchically onto the synthetic rafts at neutral pH to provide discrete Con A aggregates with a uniform size of ≈12 nm. The uniform aggregates of Con A on the synthetic rafts can stimulate Jurkat cells with enhanced efficiency, as compared with random‐sized aggregates of Con A.
Bibliometric analysis of the brazilian periodical journal of biochemistry education
Authors: do Nascimento Agatha Santos , de Oliveira Felipe Sales , Bianconi M. Lucia 
Published: February 2019

AbstractThe bibliometric analysis of the Brazilian periodical Journal of Biochemistry Education (JBE) covered the 117 articles published in 15 volumes in the period 2001–2017. Our results showed a positive trend in JBE publications with a significant increase in the number of articles since 2014, which can be related to the increase in research groups working in this area. The Southeast region of Brazil was the most productive one mainly due to the contribution of papers from institutions located in the State of São Paulo. Only four articles aimed the undergraduate courses (87.0%) showing methodological approaches to teach biochemistry (51.3%) and laboratory exercises (18.8%) among others. Most of the 332 authors contributed to a single article (87.7%) and just 3% of them published more than twice in JBE. The majority of the JBE articles had at least one citation in Google Scholar. There is also a great variety in the references used by the authors. Our analysis showed that JBE is an important peer reviewed publication aimed to improve teaching and learning of Biochemistry in Brazil. © 2019 International Union of Biochemistry and Molecular Biology, 47(3):249–256, 2019.
Exploring external and internal pressures on the environmental behavior of paper enterprises in China: A qualitative study
Authors: He Zhengxia , Xu Shichun , Shen Wenxing , Wang Meiling , Li Cunfang 
Published: February 2019

AbstractAs one of the typical high‐polluting and high‐energy‐consuming industries in China, the paper industry's environmental behavior has become the focus of a range of stakeholders, policy makers, and the whole society because the industry's business activities are a main source of environmental pollution and contribute to massive energy consumption. This study used a qualitative approach to examine the relative importance of external and internal pressures (EP and IP) in driving the environmental behavior of paper enterprises in China. Based on grounded theory, this study aimed to examine the EP and IP on the environmental behavior of paper enterprises to create a comprehensive theoretical model based on grounded theory code analysis. It was found that government pressure, economic pressure, social pressure, and IP have direct and significant positive effects on the corporate environmental behavior (CEB) of paper enterprises in China. Furthermore, government, economic, and social pressures have indirect and significant positive effects on CEB through other pressures. Finally, the paper concludes with a discussion of these four pressures and provides policy implications.
Cytotoxic Activity and Related Mechanisms of Prenylflavonoids Isolated fromMallotus conspurcatusCroizat
Authors: Zhang Yanjun , Zhou Dexiong , Liu Wei , Li Chenguo , Hao Lili , Zhang Gaorong , Deng Shengping , Yang Ruiyun , Qin Jiangke , Li Jun , Deng Wei 
Published: February 2019

AbstractFive prenylflavonoids, 6‐prenylnaringenin (1), 8‐prenylnaringenin (2), 7‐O‐methyl‐8‐prenylnaringenin (3), 7‐O‐methyl‐6‐prenylnaringenin (4), and 4′‐O‐methyl‐6‐prenylnaringenin (5), were isolated from the traditional herbMallotus conspurcatusCroizat(Euphorbiaceae). Compounds1–5revealed cytotoxic activity against cervical cancer (HeLa) cells with IC50values ranging from 10.08 to 60.16 μmby MTT method, and interestingly, these prenylflavonoids were less toxic to normal HL‐7702 cells. Furthermore, compounds1and5could inhibit the c‐myc expression and telomerase activity and cause mitochondrial dysfunction. These findings might contribute to a better understanding of the biological activities of prenylflavonoids and lay the foundation for further studies on the cytotoxic activity of natural products isolated fromM. conspurcatus.
Supported Cobalt Nanoparticles for Hydroformylation Reactions
Authors: Hertrich Maximilian Franz , Scharnagl Florian Korbinian , Pews‐Davtyan Anahit , Kreyenschulte Carsten Robert , Lund Henrik , Bartling Stephan , Jackstell Ralf , Beller Matthias 
Published: February 2019

AbstractHydroformylation of olefins has been studied in the presence of specific heterogeneous cobalt nanoparticles. The catalytic materials were prepared by pyrolysis of preformed cobalt complexes deposited onto different inorganic supports. Atomic absorption spectroscopy (AAS) measurements indicated a correlation of catalyst activity and cobalt leaching as well as a strong influence of the heterogeneous support on the productivity. These new, low‐cost, easy‐to‐handle catalysts can substitute more toxic, unstable and volatile cobalt carbonyl complexes for hydroformylations on a laboratory scale.
What Are We Missing by Not Measuring the Net Charge of Proteins?
Authors: Zahler Collin T. , Shaw Bryan F. 
Published: February 2019

AbstractThe net electrostatic charge (Z) of a folded protein in solution represents a bird's eye view of its surface potentials—including contributions from tightly bound metal, solvent, buffer, and cosolvent ions—and remains one of its most enigmatic properties. Few tools are available to the average biochemist to rapidly and accurately measure Z at pH≠pI. Tools that have been developed more recently seem to go unnoticed. Most scientists are content with this void and estimate the net charge of a protein from its amino acid sequence, using textbook values of pKa. Thus, Z remains unmeasured for nearly all folded proteins at pH≠pI. When marveling at all that has been learned from accurately measuring the other fundamental property of a protein—its mass—one wonders: what are we missing by not measuring the net charge of folded, solvated proteins? A few big questions immediately emerge in bioinorganic chemistry. When a single electron is transferred to a metalloprotein, does the net charge of the protein change by approximately one elementary unit of charge or does charge regulation dominate, that is, do the pKa values of most ionizable residues (or just a few residues) adjust in response to (or in concert with) electron transfer? Would the free energy of charge regulation (ΔΔGz) account for most of the outer sphere reorganization energy associated with electron transfer? Or would ΔΔGz contribute more to the redox potential? And what about metal binding itself? When an apo‐metalloprotein, bearing minimal net negative charge (e.g., Z=−2.0) binds one or more metal cations, is the net charge abolished or inverted to positive? Or do metalloproteins regulate net charge when coordinating metal ions? The author's group has recently dusted off a relatively obscure tool—the “protein charge ladder”—and used it to begin to answer these basic questions.
Morphological characteristics of p75 neurotrophin receptor‐positive cells define a new type of glial cell in the rat dorsal root ganglia
Authors: Koike Taro , Tanaka Susumu , Hirahara Yukie , Oe Souichi , Kurokawa Kiyoshi , Maeda Mitsuyo , Suga Mitsuo , Kataoka Yosky , Yamada Hisao 
Published: February 2019

AbstractIn the dorsal root ganglia (DRG), two types of glial cells (Schwann cells and satellite glial cells) have been identified based on cell morphology and expression of specific markers. In the present study, we observed unknown glial cells that were positive for p75 neurotrophin receptor (p75NTR), and therefore were immunohistochemically and ultrastructurally characterized for the first time. These cells exhibited stronger immunoreactivity against an anti‐p75NTR antibody than the DRG neurons (hereafter referred to as p75NTR++ cells). Moreover, these cells covered the glial cells surrounding proximal process of the large‐diameter DRG neurons. The proximal process is called “dendro‐axon.” The p75NTR++ cells were predominantly distributed where the first myelinating Schwann cells appear. The p75NTR++ cells were also positive for the pan‐glial cell markers S100, nestin, and Sox10, but negative for fibroblast and macrophage markers. Moreover, they were negative for a satellite glial cell marker, inwardly rectifying potassium channel Kir4.1, as well as a nonmyelinating Schwann cell marker, glial fibrillary acidic protein. In addition, their morphological features were distinct from those of the myelinating Schwann cells. To investigate the three‐dimensional ultrastructure of the p75NTR++ cells, we used array tomography combined with correlative light and electron microscopic observation. Three‐dimensional ultrastructural observation revealed that the p75NTR++ cells loosely covered glial cells around the dendro‐axons with highly ramified processes. Glial cells with these morphological features have not been reported before, indicating that the p75NTR++ glial cells are a new glial cell type in the DRG. Our results will give new insights into cell–cell relationships.
CEOs' religious beliefs and the environmental innovation of private enterprises: The moderating role of political ties
Authors: Liao Zhongju , Dong Jincai , Weng Chen , Shen Chen 
Published: February 2019

AbstractEnvironmental innovation is an important way for enterprises to take social responsibility. Based on upper echelons theory, this study constructed a model of the relationship of religious beliefs, political ties, and environmental innovation. The CEOs of 196 Chinese private enterprises were selected as the research sample, and the multiple regression analysis method was used to test the influence of the CEOs' religious beliefs on the environmental innovation of the enterprises, as well as the moderating role of the CEOs' political ties. The results showed that CEOs' Eastern religious beliefs had a positive effect on the incremental eco‐innovation of the private enterprises and a negative effect on radical eco‐innovation. However, the CEOs' Western religious beliefs had a negative effect on the incremental eco‐innovation of the private enterprises and a positive effect on radical eco‐innovation. In addition, the results showed that political ties played a positive moderating role between the CEOs' Eastern religion beliefs and the incremental eco‐innovation and between CEOs' Western religion beliefs and the radical eco‐innovation of the private enterprises.
A fast realization of new Mersenne number transformation and its applications
Authors: Hua Jingyu , Liu Fei , Xu Zhijiang , Li Feng , Wang Dongming 
Published: February 2019

SummaryThe new Mersenne number transform (NMNT) can be realized by the fast Fourier transform (FFT) with power‐of‐two length, which results in great flexibility in real‐world fixed‐point computations, such as the convolution‐based signal processing in the embedded device. Yet the FFT realization exists the truncation errors and in order to further reduce the computations, this paper puts forward a novel realization structure for the NMNT, where the Walsh‐Hadamard transform (WHT) is employed to accelerate the NMNT computation. Moreover, we also propose the refined computing structure using the matrix decomposition and multiple constant multiplication (MCM), and then all multiplications can be replaced by the shift‐addition operations without precision loss. Besides, the use of lookup table (LUT) to reduce the complexity is also discussed in our study. A typical convolution application is tested by computer simulations, while the result demonstrates that the proposed scheme produces precise computing results with reduced complexity.
Fluvio‐lacustrine sedimentation in the Agadir‐Tissint Feija (Anti‐Atlas, Morocco): A promising palaeoclimate archive for the last glacial cycle in northwest Africa
Authors: Nutz Alexis , Kwiecien Ola , Breitenbach Sebastian F. M. , Cai Yanjun , Della Porta Giovanna , Danisch Jan , Kabiri Lahcen , Bodin Stéphane 
Published: February 2019

AbstractMountainous depocentres are often the single available archives in intracontinental areas. As such, the investigation of their sedimentary dynamics is the only way to reconstruct palaeoenvironmental evolution in these peculiar regions. Here, the basin‐scale sedimentary dynamics of the Agadir‐Tissint Feija (i.e. feija is the local name for lowlands) are discussed together with new palaeoenvironmental information on the late Quaternary in the north‐western Sahara margin. The succession consists of up to ca 40 m thick fluvio‐lacustrine deposits subdivided into three depositional sequences (S1–S3) that were deposited between ca 75 ka and ca 10 ka. S1 and S2 reflect the evolution of a palaeolake intercalated by carbonate‐rich palustrine to alluvial plain environments, while S3 shows the transition to an entirely clastic alluvial plain environment. The three sequences are genetically associated with three pulses of tufa buildups at the outlet of the depocentre. Each pulse of tufa buildup is attributed to wet conditions, while each interruption is associated with drier conditions. The wet–dry alternation at the origin of S1 fits with summer insolation fluctuation suggesting that precession parameters may have paced long‐term climate variability in the area. Superimposed on wet–dry cycles, submillennial‐scale (750–900 year) shorter‐term lake fluctuations are identified in S1 and S2; their origins may be related to North Atlantic Oscillation mechanisms. Furthermore, the sudden increase in clastic sediment supply in S3 evidences a change in sediment production in the catchment area attributed to lower temperatures established during the last glacial period. Finally, this newly identified continental archive is unique at the northern Sahara margin; it enables reconstructions of the local and regional hydrological conditions during the last glacial cycle. Even if a more systematic investigation of palaeoclimate forcing is still necessary, the Agadir‐Tissint Feija will potentially bring important information to understand past and anticipate future regional climate change.