bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ocean acidification and nutrient limitation synergistically reduce growth and photosynthetic performances of a green tide alga Ulva linza
Authors: Gao Guang , Beardall John , Bao Menglin , Wang Can , Ren Wangwang , Xu Juntian 
Published: June 2018

Abstract. Large-scale green tides have been invading the coastal zones of the western Yellow Sea annually since 2008. Meanwhile, oceans are becoming more acidic due to continuous absorption of anthropogenic carbon dioxide, and intensive seaweed cultivation in Chinese coastal areas is leading to severe regional nutrient limitation. However, little is known about the combined effects of global and local stressors on the eco-physiology of bloom-forming algae. We cultured Ulva linza for 9–16 days under two levels of pCO2 (400 and 1000 µatm) and four treatments of nutrients (nutrient repletion, N limitation, P limitation, and N–P limitation) to investigate the physiological responses of this green tide alga to the combination of ocean acidification and nutrient limitation. For both sporelings and adult plants, elevated pCO2 did not affect the growth rate when cultured under nutrient-replete conditions but reduced it under P limitation; N or P limitations by themselves reduced growth rate. P limitation resulted in a larger inhibition in growth for sporelings compared to adult plants. Sporelings under P limitation did not reach the mature stage after 16 days of culture while those under P repletion became mature by day 11. Elevated pCO2 reduced net photosynthetic rate for all nutrient treatments but increased nitrate reductase activity and soluble protein content under P-replete conditions. N or P limitation reduced nitrate reductase activity and soluble protein content. These findings indicate that ocean acidification and nutrient limitation would synergistically reduce the growth of Ulva species and may thus hinder the occurrence of green tides in a future ocean environment.
Asymmetric responses of primary productivity to altered precipitation simulated by ecosystem models across three long-term grassland sites
Authors: Wu Donghai , Ciais Philippe , Viovy Nicolas , Knapp Alan K. , Wilcox Kevin , Bahn Michael , Smith Melinda D. , Vicca Sara , Fatichi Simone , Zscheischler Jakob , He Yue , Li Xiangyi , Ito Akihiko , Arneth Almut , Harper Anna , Ukkola Anna , Paschalis Athanasios , Poulter Benjamin , Peng Changhui , Ricciuto Daniel , Reinthaler David , Chen Guangsheng , Tian Hanqin , Genet Hélène , Mao Jiafu , Ingrisch Johannes , Nabel Julia E. S. M. , Pongratz Julia , Boysen Lena R. , Kautz Markus , Schmitt Michael , Meir Patrick , Zhu Qiuan , Hasibeder Roland , Sippel Sebastian , Dangal Shree R. S. , Sitch Stephen , Shi Xiaoying , Wang Yingping , Luo Yiqi , Liu Yongwen , Piao Shilong 
Published: June 2018

Abstract. Field measurements of aboveground net primary productivity (ANPP) in
temperate grasslands suggest that both positive and negative asymmetric
responses to changes in precipitation (P) may occur. Under normal range of
precipitation variability, wet years typically result in ANPP gains being
larger than ANPP declines in dry years (positive asymmetry), whereas
increases in ANPP are lower in magnitude in extreme wet years compared to
reductions during extreme drought (negative asymmetry). Whether the current
generation of ecosystem models with a coupled carbon–water system in
grasslands are capable of simulating these asymmetric ANPP responses is an
unresolved question. In this study, we evaluated the simulated responses of
temperate grassland primary productivity to scenarios of altered
precipitation with 14 ecosystem models at three sites: Shortgrass
steppe (SGS), Konza Prairie (KNZ) and Stubai Valley meadow (STU), spanning a
rainfall gradient from dry to moist. We found that (1) the spatial slopes
derived from modeled primary productivity and precipitation across sites were
steeper than the temporal slopes obtained from inter-annual variations, which
was consistent with empirical data; (2) the asymmetry of the responses of
modeled primary productivity under normal inter-annual precipitation
variability differed among models, and the mean of the model ensemble
suggested a negative asymmetry across the three sites, which was contrary to
empirical evidence based on filed observations; (3) the mean sensitivity of
modeled productivity to rainfall suggested greater negative response with
reduced precipitation than positive response to an increased precipitation
under extreme conditions at the three sites; and (4) gross primary productivity
(GPP), net primary productivity (NPP), aboveground NPP (ANPP) and belowground
NPP (BNPP) all showed concave-down nonlinear responses to altered
precipitation in all the models, but with different curvatures and mean
values. Our results indicated that most models overestimate the negative
drought effects and/or underestimate the positive effects of increased
precipitation on primary productivity under normal climate conditions,
highlighting the need for improving eco-hydrological processes in those
models in the future.
Brexit and Universities: Toward a Reconfiguration of the European Higher Education Sector?
Authors: Courtois Aline 
Published: June 2018

The prospect of “Brexit” is causing significant anxiety across the European higher education sector, as universities brace themselves for a possible departure of the United Kingdom and a reconfiguration of the sector. Our research suggests that while the impact is expected to be uneven across the region—with some possible short-term beneficiaries—research cooperation with the United Kingdom and freedom of movement are valued by universities across the region.
Inclusive Internationalization: Improving Access and Equity
Authors: De Wit Hans , Jones Elspeth 
Published: June 2018

In higher education, we are faced with two main paradoxes. First, while we may be striving to increase internationalization and global engagement, in many countries isolationist and nationalist trends result in a disconnect between local and global. Second, while credit and degree mobility is increasing globally, this billion-dollar industry reaches only a small student elite, leaving 99 percent of the world’s student population behind. An inclusive approach must address the issue that current internationalizationpolicies and practices leave out the great majority of students in the world. Internationalization for all should be the starting point for institutional strategies, reflecting an awareness that all students must be engaged in this agenda to prepare for their future lives as citizens and as professionals.
The "Champagne Tower" of Science Publishing
Authors: Siebert Sabina 
Published: June 2018

This article discusses the hierarchical nature of science publishing, whereby journals are organized in tiers with the most prestigious elite journals at the top (Cell, Nature, Science), and lowest-ranked journals at the bottom. When rejected from the top-tier journals, authors usually aim for a lower tier of journals, with some choosing smaller, specialist journals for the outlet of their work. Recently, however, a differentmechanism of cascading the papers down the hierarchy of journals has become popular, i.e., editors arrange to pass the rejected papers, with the authors’ permission, to their “sister journals” bearing the same brand. These transfer arrangements may be seen beneficial for the authors, as they reduce the publication time, but they also pose difficulties for smaller specialist journals that lose their shareof the market and experience a fall in manuscript submissions.
Two new species of Primulina (Gesneriaceae) from limestone karsts of China
Authors: Hong Xin , Li Zhong-Lin , Liu Jia-Zhi , Zhou Shou-Biao , Qin Wei-Hua , Wen Fang 
Published: June 2018

The limestone karst area of South China is a major biodiversity hotspot of global terrestrial biomes. During extensive field work on the Guangxi limestone formations, two unknown species of Gesneriaceae were collected. After conducting a comprehensive study of the literature and herbarium specimens, Primulina davidioides and P. hiemalis are recognized as two species new to science, and described and illustrated here. P. davidioides is morphologically close to P. lunglinensis based on the shape of the leaf and flower, but it can be easily distinguished by the shape of the bracts, corolla and stigma, indumentum of peduncles, pedicels and pistil and number of staminodes. P. hiemalis is closely relate to P. luzhaiensis in vegetative appearance, but differs in the shape of the calyx and stigma, number of bracts and staminodes, indumentum of the leaf blade and peduncle, and position of stamens in the corolla tube. Considering that not enough is known about their populations, it is proposed that their conservation statuses should currently be classed as data deficient (DD) according to the IUCN Red List Category and Criteria.
Fish Skin: A Natural Inspiration for Innovation
Authors: Drelich Adam J. , Monteiro Sergio N. , Brookins Jeffrey , Drelich Jaroslaw W. 
Published: June 2018

AbstractNatural materials and the structures they form, developed and perfected through millions of years of evolution, have long inspired researchers for innovations in science and engineering. One example, fish scales are notable for their strength, toughness, flexibility, and lightweight. These properties are the result of collagen fibrils and hydroxyapatite crystals that have been arranged into three‐layer structures through mechanical locking and chemical bonds, via a process that is still poorly understood. This review aims to compile the established knowledge on the composition, structure, and surface/interfacial features of fish scales. Using mainly Arapaima gigas as a focus, published information and supplementary data acquired through imaging, analytical techniques, and tensiometry are combined. This is done to take a closer look at the surfaces and interfaces of fish scales to identify their unique features and begin to overcome some of the limited understanding of surface functionalities that are created by nature.
Unraveling the Water Impermeability Discrepancy in CVD‐Grown Graphene
Authors: Kwak Jinsung , Kim Se‐Yang , Jo Yongsu , Kim Na Yeon , Kim Sung Youb , Lee Zonghoon , Kwon Soon‐Yong 
Published: June 2018

AbstractGraphene has recently attracted particular interest as a flexible barrier film preventing permeation of gases and moistures. However, it has been proved to be exceptionally challenging to develop large‐scale graphene films with little oxygen and moisture permeation suitable for industrial uses, mainly due to the presence of nanometer‐sized defects of obscure origins. Here, the origins of water permeable routes on graphene‐coated Cu foils are investigated by observing the micrometer‐sized rusts in the underlying Cu substrates, and a site‐selective passivation method of the nanometer‐sized routes is devised. It is revealed that nanometer‐sized holes or cracks are primarily concentrated on graphene wrinkles rather than on other structural imperfections, resulting in severe degradation of its water impermeability. They are found to be predominantly induced by the delamination of graphene bound to Cu as a release of thermal stress during the cooling stage after graphene growth, especially at the intersection of the Cu step edges and wrinkles owing to their higher adhesion energy. Furthermore, the investigated routes are site‐selectively passivated by an electron‐beam‐induced amorphous carbon layer, thus a substantial improvement in water impermeability is achieved. This approach is likely to be extended for offering novel barrier properties in flexible films based on graphene and on other atomic crystals.
New Frontiers in Electron Beam–Driven Chemistry in and around Graphene
Authors: Rummeli Mark H. , Ta Huy Q. , Mendes Rafael G. , Gonzalez‐Martinez Ignacio G. , Zhao Liang , Gao Jing , Fu Lei , Gemming Thomas , Bachmatiuk Alicja , Liu Zhongfan 
Published: June 2018

AbstractModern aberration corrected transmission electron microscopes offer the potential for electron beam sensitive materials, such as graphene, to be examined with low energy electrons to minimize, and even avoid, damage while still affording atomic resolution, and thus providing excellent characterization. Here in this review, the exploits in which the electron beam interactions, which are often considered negative, are explored to usefully drive a wealth of chemistry in and around graphene, importantly, with no other external stimuli. After introducing the technique, this review covers carbon phase reactions between amorphous carbon, graphene, fullerenes, carbon chains, and carbon nanotubes. It then explores different studies with clusters and nanoparticles, followed by coverage of single atom and molecule interactions with graphene, and finally concludes and highlights the anticipated exciting future for electron beam driving chemistry in and around graphene.
Epitaxial Growth of Single‐Layer Niobium Selenides with Controlled Stoichiometric Phases
Authors: Cheng Fang , Ding Zijing , Xu Hai , Tan Sherman J. R. , Abdelwahab Ibrahim , Su Jie , Zhou Pinjia , Martin Jens , Loh Kian Ping 
Published: June 2018

AbstractThe phase diagram of 2D monolayer material often differs from the bulk crystal due to electronic instability and interactions with the substrate. At the monolayer level, stoichiometric phases can transform into substoichiometric crystalline phases due to changes in chemical potential, however conditions leading to this are still relatively unexplored. Here, the growth of two distinct phases of niobium selenide by tuning the chemical potential during molecular beam epitaxy (MBE) is demonstrated. NbSe2 monolayers are grown on Au(111) under Se‐rich (low Nb:Se flux ratio) condition, whereas a new phase of niobium selenide (NbSex) monolayers is formed under Nb‐rich (high Nb:Se flux ratio) condition. Scanning tunnelling microscopy and spectroscopy are employed to investigate the geometric and electronic structures of the as‐grown NbSe2 and NbSex phases. The NbSex phase is identified as Nb9Se8 through experimental and theoretical investigation; its distorted single‐layer structure indicates a dimensionality induced reconstruction compared with its bulk counterpart (Nb3Se4). This work shows that MBE affords a high degree of control in growing complex chemical phases, which should be applicable to other metallic transition metal dichalcogenides system.
A Smart Artificial Finger with Multisensations of Matter, Temperature, and Proximity
Authors: Zhao Shuai , Zhu Rong 
Published: June 2018

AbstractSmart robots interact with their environment or collaborators through acquiring information from their visual, acoustic, and tactile sensing systems, which are developed into a high sophisticated stage. However, expedient and fast sense perceptions for safety and intelligent control of collaborative robots still remain great challenges. Here, a smart artificial finger with multisensations of matter, temperature, and proximity, which enriches its sensory system for comprehensive learning of the object it touches is proposed. The finger sensor is composed of two thermosensitive platinum ribbons on a polyimide substrate, which detect thermal properties of surroundings, that is, temperature and thermal conductivity, from which surrounding matter is identified. The sensor has a large range of detectability for discriminating diverse matters from cotton to metal, perceiving temperature stimulus and approaching object. The applications of identifying matter type, sensing proximity distance, and monitoring moisture and temperature of human skin are demonstrated. The smart finger provides promising approaches to enhance intelligence and safety of smart robots.
Ultrahigh Power Efficiency Thermally Activated Delayed Fluorescent OLEDs by the Strategic Use of Electron‐Transport Materials
Authors: Sasabe Hisahiro , Sato Ryo , Suzuki Katsuaki , Watanabe Yuichiro , Adachi Chihaya , Kaji Hironori , Kido Junji 
Published: June 2018

AbstractThermally activated delayed fluorescent (TADF) emitters are one of the most promising candidates for developing low‐cost organic light‐emitting devices (OLEDs) that can achieve an internal quantum efficiency of 100%. However, the power efficiency values are still significantly lower than that of their phosphorescent counterparts. To achieve high power efficiency, both a high external quantum efficiency and low drive voltage are required. Here, TADF OLEDs with an ultrahigh power efficiency of 133 lm W−1 and an unprecedented low turn‐on voltage of 2.22 V are successfully developed via the strategic use of electron‐transport materials (ETMs). 9‐[4‐(4,6‐Diphenyl‐1,3,5‐triazin‐2‐yl)phenyl]‐N,N,N′,N′‐tetraphenyl‐9H‐carbazole‐3,6‐diamine as a TADF emitter is used. A series of green TADF OLEDs are fabricated using two different types of pyrimidine‐based ETMs as an exciplex host partner and electron‐transport layer to minimize the drive voltages. The optimized device shows an external quantum efficiency of 29.2% and maximum power efficiency of 133.2 lm W−1 without any light‐outcoupling enhancement. The device also shows 124.0 lm W−1 at 100 cd m−2 and 95.2 lm W−1 at a high brightness of 1000 cd m−2. The drive voltages are 2.48 V at 100 cd m−2 and 2.88 V at 1000 cd m−2.
Soft Materials Driven by Photothermal Effect and Their Applications
Authors: Bisoyi Hari Krishna , Urbas Augustine M. , Li Quan 
Published: June 2018

AbstractRemote driving of functional hybrid soft materials for various applications is emerging as an enabling pursuit. Toward this end, soft materials driven by photothermal agents have been attracting tremendous attention from both fundamental science and technological applications points of view. These stimuli‐responsive materials combine the beneficial attributes of both classes of promising materials, i.e., soft materials and photothermal agents. Both inorganic and organic photothermal agents have been incorporated into the matrices of soft materials. Metal nanoparticles, carbon nanomaterials, and organic photothermal agents have been impregnated into the matrices of liquid crystals, polymers, and gels that can be remotely driven by light irradiation. In this review, the remote driving of functional hybrid soft materials and their various applications are discussed. Photothermal functional nanocomposites are demonstrated to act as actuators, therapeutic agents, drug delivery systems, microvalves, etc. Smart and adaptive systems are realized by dispersing photothermal agents into soft matter matrices. Challenges and opportunities in this fascinating frontier are outlined.
Mesoporous Carbon Nanospheres as Broadband Saturable Absorbers for Pulsed Laser Generation
Authors: Wang Fang , Jing Ying , Kang Zhe , Zhou Libo , Li Zhenrui , Liu Mingyi , Wang Tao , Yao Chuanfei , Chen Haobin , Qin Weiping , Qiao Zhen‐An , Qin Guanshi , Wu Changfeng 
Published: June 2018

AbstractBroadband pulsed laser generation is demonstrated by using mesoporous carbon nanospheres (MCNs) as saturable absorbers (SAs). The MCNs are prepared by a “silica‐assisted” method, and then mixed with sodium carboxymethylcellulose (NaCMC) to form the MCNs film. The film not only shows strong absorption from visible to mid‐infrared spectral region, but also possesses the nonlinear saturable absorption properties. As the MCNs film is inserted into the laser cavity, a mode‐locked laser at 1 µm and Q‐switched lasers at 1.56 and 2 µm are realized, respectively. In addition, by depositing the MCNs onto tapered fiber as an SA, a mode‐locked fiber laser at 2 µm is also demonstrated. The results show that MCNs are promising SA material for broadband pulsed laser generation.
Chiral Squaramide‐Catalyzed Asymmetric Mannich Reactions for Synthesis of Fluorinated 3,3′‐Bisoxindoles
Authors: Li Bing‐Yu , Du Da‐Ming 
Published: June 2018

AbstractA squaramide‐catalyzed asymmetric Mannich reaction of 3‐fluorooxindoles to isatin‐derived imines for synthesis of fluorinated 3,3′‐bisoxindoles with two contiguous stereocenters under mild conditions was developed. The corresponding 3,3′‐bisoxindoles were obtained in excellent yields with excellent diastereo‐ and enantioselectivities (up to 99% yield, >99:1 dr and >99% ee). What's more, this reaction can be gram‐scaled without compromising yield and stereoselectivity.magnified image
Metal‐Organic Framework‐Derived Carbons for Battery Applications
Authors: Li Xiaxia , Zheng Shasha , Jin Ling , Li Yan , Geng Pengbiao , Xue Huaiguo , Pang Huan , Xu Qiang 
Published: June 2018

AbstractThe applications of carbon and carbon‐based materials with high porosity, high surface area, and functionalities based on metal‐organic framework precursors and/or templates have attracted significant research interest in recent years, particularly in the field of batteries. The chemical and physical properties of carbon and carbon‐based materials obtained by the heat treatment of various metal‐organic framework precursors or templates are improved to a certain extent. In this comprehensive review, the synthetic methods and electrochemical performance of carbon materials derived from metal‐organic frameworks (metal/carbon, metal oxide/carbon, nitrogen‐doped carbon, porous carbon, etc.) along with their applications in batteries are outlined.
Sulfonated graphene oxide‐doped proton conductive membranes based on polymer blends of highly sulfonated poly(ether ether ketone) and sulfonated polybenzimidazole
Authors: Gao Shuitao , Chen Xin , Xu Hulin , Luo Tianwei , Ouadah Amina , Fang Zhou , Li Yang , Wang Run , Jing Chaojun , Zhu Changjin 
Published: June 2018

ABSTRACTSimultaneously improving the proton conductivity and mechanical properties of a polymer electrolyte membrane is a considerable challenge in commercializing proton exchange membrane fuel cells. In response, we prepared a new series of miscible polymer blends and thus the corresponding crosslinked membranes based on highly sulfonated poly(ether ether ketone) and sulfonated polybenzimidazole. The blended membranes showed more compact structures, due to the acid‐base interactions between the two constituents, and improved mechanical and morphological properties. Further efforts by doping sulfonated graphene oxide (s‐GO) forming composite membranes led to not only significantly elevated proton conductivity and electrochemical performance, but also better mechanical properties. Notably, the composite membrane with the filler content of 15 wt % exhibited a proton conductivity of 0.217 S cm−1 at 80 °C, and its maximum power density tested by the H2/air single PEMFC cell at room temperature reached 171 mW cm−2, almost two and half folds compared with that of the native membrane. As a result, these polymeric membranes provided new options as proton exchange membranes for fuel‐cell applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46547.
Colloidal Synthesis of NiWSe Nanosheets for Efficient Electrocatalytic Hydrogen Evolution Reaction in Alkaline Media
Authors: Zhao Yuanmeng , Mao Guixiang , Du Yeshuang , Cheng Gongzhen , Luo Wei 
Published: June 2018

AbstractSearching for efficient, low‐cost, and durable electrocatalysts toward the hydrogen evolution reaction (HER) is extremely urgent for future energy conversion systems. Herein, the colloidal synthesis of 2D tungsten‐doped nickel selenide nanosheets by using Ni(acac)2 (acac=aceylacetonate), [W(CO)6], and selenium powder as precursors in oleylamine is reported. The introduction of tungsten is essential for the formation of 2D nanosheets. As a result, by taking the advantage of the unique layered structure and strong synergistic electronic effect between nickel, tungsten, and selenium, the as‐synthesized Ni0.54W0.26Se nanosheets exhibit superior catalytic activity toward the HER in alkaline media, with an overpotential of 162 mV (η10), which is much lower than those of NiSe2 (η10=330 mV) and WSe2 (η10=378 mV), and higher than that of most previously reported selenide‐based electrocatalysts.