bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding anisotropic mechanical properties of shales at different length scales: In situ micropillar compression combined with finite element calculations
Authors: Keller Lukas M. , Schwiedrzik Jakob J. , Gasser Philippe , Michler Johann 
Published: June 2017

AbstractFrom microstructural observations and experimental work it is known that shales consist of a mechanically weak porous fine‐grained clay matrix with embedded and mechanically strong silt/sand grains. Thereby, the respective contents of weak and strong constituents control bulk mechanical properties. In addition, the clay matrix is characterized by a preferred orientation of clay platelets, which are a major control on the bulk anisotropy of shales. To date, little is known about the micromechanical properties of the fine‐grained porous clay matrix, which is particularly true in case of its micromechanical anisotropy. Such information can, however, only be assessed on the microscale. Therefore, the drained micromechanical properties parallel and perpendicular to bedding were investigated by means of compressing micropillars with a flat punch indenter in a scanning electron microscope. Microscopic failure mechanism was found to be anisotropic: (i) in case loading was parallel to bedding it occurred by a combination of localized shearing, kinking/buckling of elongated clay aggregates, and bedding parallel splitting and (ii) for loading perpendicular to bedding failure occurred mainly by localized shearing. The measured stiffness of the drained porous clay matrix perpendicular (Ev) and parallel (Eh) to bedding was about 8 GPa and 30 GPa, respectively. Using these stiffness values as input in voxel‐based finite element modeling and in combination with realistic microstructures, which are characterized with different contents of “soft” and “hard” constituents, revealed that the measured high microscale anisotropy Eh/Ev = 3.75 is crucial in understanding the bulk anisotropy of clay rocks.
Opening Two‐Dimensional Materials for Energy Conversion and Storage: A Concept
Authors: Xue Yinghui , Zhang Qin , Wang Wenjie , Cao Hui , Yang Quanhong , Fu Lei 
Published: June 2017

AbstractThe development of two‐dimensional (2D) materials is experiencing a renaissance since the adventure of graphene. 2D materials typically exhibit strong in‐plane covalent bonding and weak out‐of‐plane van der Waals interactions through the interlayer gap. Opening 2D materials is an effective way to alter the physical and chemical properties, such as band gap, conductivity, optical property, thermoelectric property, photovoltaic property and superconductivity. A larger interlayer distance means more accessible active sites for catalysis, an ion‐accessible surface in the interlayer space, which may greatly enhance the performance of 2D materials for energy conversion and storage. Moreover, opening 2D materials by intercalation can change the band filling state and the Fermi level. This review mainly focuses on the opening of 2D materials and their subsequent applications in energy conversion and storage fields, expecting to promote the development of such a new class of materials, namely expanded 2D materials. The exciting progresses of these expanded materials made in both energy conversion and storage devices including solar cells, thermoelectric devices, electrocatalyst, supercapacitors and rechargeable batteries, is presented and discussed in depth. Furthermore, prospects and further developments in these exciting fields of the expanded 2D materials are also commented.
The Emergence of the Mixed Perovskites and Their Applications as Solar Cells
Authors: Xiao Jia‐Wen , Liu Lang , Zhang Deliang , De Marco Nicholas , Lee Jin‐Wook , Lin Oliver , Chen Qi , Yang Yang 
Published: June 2017

AbstractThe halide perovskite (PVSK) materials (with ABX3 formulation) have emerged as “dream materials” for photovoltaic (PV) applications due to their remarkable physical properties such as high optical absorption coefficient, carrier mobility, long carrier diffusion lengths, etc. These properties have enabled the PV devices to reach higher than 20% power conversion efficiencies (PCE) in record time. The further pursuit of higher PCE and improved stability brings forth increasing interests in so‐called “mixed composition” PVSK materials, consisting of partial substitution of the A, B, and/or X‐sites with alternative elements/molecules of similar size. Herein, we highlight the recent advances in developing mixed PVSK for PVs and their relevant optoelectronic properties. We mainly focus on mixed PVSK materials in the form of polycrystalline thin films, but also discuss nanostructured and two‐dimensional (2D) PVSK materials due to the increasing interest of broad readership. Efforts are exerted to elucidate the design principles of mixed PVSK and fabrication techniques for high performance optoelectronic devices, which help deepen our fundamental understanding of mixed PVSK systems. We hope this review will shed light onto the design and synthesis of mixed PVSK materials to further the progress of PVSK photovoltaics towards higher efficiencies and longer lifetimes.
Design Strategies toward Advanced MOF‐Derived Electrocatalysts for Energy‐Conversion Reactions
Authors: Liu Jinlong , Zhu Dongdong , Guo Chunxian , Vasileff Anthony , Qiao Shi‐Zhang 
Published: June 2017

AbstractThe key challenge to developing renewable and clean energy technologies lies in the rational design and synthesis of efficient and earth‐abundant catalysts for a wide variety of electrochemical reactions. This review presents materials design strategies for constructing improved electrocatalysts based on MOF precursors/templates, with special emphasis on component manipulation, morphology control, and structure engineering. Guided by these strategies, recently developed MOF‐derived materials have exhibited remarkable activity, selectivity, and stability for various energy‐conversion processes, manifesting great potential for replacing precious‐metal‐based catalysts in next‐generation energy devices. Existing challenges and opportunities regarding MOF‐derived electrocatalysts are also discussed. It is anticipated that by extending current materials design strategies to a wider range of MOF precursors for various energy‐related electrocatalytic reactions, significant advances toward achieving highly efficient electrocatalysts can be made.
Hourglass Triboelectric Nanogenerator as a “Direct Current” Power Source
Authors: He Chuan , Han Chang Bao , Gu Guang Qin , Jiang Tao , Chen Bao Dong , Gao Zhen Liang , Wang Zhong Lin 
Published: June 2017

AbstractHourglass, or sandglass, is known for centuries to record the passage of time. Here, an hourglass triboelectric nanogenerator (HG‐TENG) is reported as a power source by harnessing the kinetic energy of falling particles. By employing the geometry of an hourglass and replacing the sand with a mixture of polytetrafluoroethylene (PTFE) pellets and Al balls, the HG‐TENG delivers a train of electrical pulses of the same sign without a rectifier bridge. When the volume ratio of the PTFE pellets to the Al balls is 1:1, the HG‐TENG is able to light up 160 commercial light emitting diodes intermittently for 18 s. Furthermore, it is demonstrated that the HG‐TENG can also serve as a self‐powered UV counterfeit detector.
Gluing Ionic Liquids to Oxide Surfaces: Chemical Anchoring of Functionalized Ionic Liquids by Vapor Deposition onto Cobalt(II) Oxide
Authors: Xu Tao , Waehler Tobias , Vecchietti Julia , Bonivardi Adrian , Bauer Tanja , Schwegler Johannes , Schulz Peter S. , Wasserscheid Peter , Libuda Joerg 
Published: June 2017

AbstractIonic liquids (IL) hold a great potential as novel electrolytes for applications in electronic materials and energy technology. The functionality of ILs in these applications relies on their interface to semiconducting nanomaterials. Therefore, methods to control the chemistry and structure of this interface are the key to assemble new IL‐based electronic and electrochemical materials. Here, we present a new method to prepare a chemically well‐defined interface between an oxide and an IL film. An imidazolium‐based IL, which is carrying an ester group, is deposited onto cobalt oxide surface by evaporation. The IL binds covalently to the surface by thermally activated cleavage of the ester group and formation of a bridging carboxylate. The anchoring reaction shows high structure sensitivity, which implies that the IL film can be adhered selectively to specific oxide surfaces.
Tire tread compounds with reduced rolling resistance and improved wet grip
Authors: Veiga Viviane Dall'Agnol , Rossignol Taline Marchesini , Crespo Janaina da Silva , Carli Larissa Nardini 
Published: June 2017

ABSTRACTThe aim of this work is to investigate the replacement of carbon black by silica‐organosilane coupling agent system and the number of processing steps on the mechanical properties, rolling resistance, and wet grip of truck tire treads. Eight compounds were prepared: two formulations based on carbon black, five formulations with the partial replacement of carbon black by a silica‐organosilane coupling agent system, and one formulation with the total replacement of carbon black with silica. The rolling resistance decreased by 10% and the wet grip increased by 18.5% for the compound with 15 phr of silica, 3 phr of organosilane, and three processing steps compared to the standard compound. The processing steps also promoted an improvement in these properties for the composition with 50 phr of carbon black. The partial use of silica reduced the abrasion loss, thus confirming the durability of the compound. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45334.
Examining horizontal and vertical social ties to achieve social–ecological fit in an emerging marine reserve network
Authors: Alexander Steven M. , Armitage Derek , Carrington Peter J. , Bodin Örjan 
Published: June 2017

Abstract

Most MPA networks are designed only with ecological processes in mind to increase their conservation utility. However, since MPA networks often involve large geographic areas, they also affect and involve multiple actors, institutions, and policy sectors.
A key challenge when establishing an effective MPA network is to align the ‘social system’ with the biophysical MPA network (the ‘ecological system’). This challenge is often denoted as ‘social–ecological fit’.
Facilitating collaborative social interactions among various actors and stakeholders (social connectivity) is equally as important as accomplishing ecological connectivity. New analytical approaches are required to effectively examine this ‘social’ dimension of fit.
An emerging marine reserve network in Jamaica and the recent invasion of Indo‐Pacific lionfish are used as a case study to: (1) examine the extent to which horizontal and vertical social ties bring local and national actors together to collaborate, coordinate, and share knowledge; and (2) assess the extent to which different attributes and features of such multilevel social networks may enhance or inhibit particular aspects of social–ecological fit.
Findings suggest that multilevel linkages have played the greatest role in relation to enhancing fit in the marine reserve network in the context of the recent lionfish invasion. However, the long‐term propensity of the multi‐actor and multilevel networks to enhance social–ecological fit is uncertain given the prevalence of weak social ties, lack of a culture of information sharing and collaboration, and limited financial resources.
Metabolic modeling of energy balances in Mycoplasma hyopneumoniae shows that pyruvate addition increases growth rate
Authors: Kamminga Tjerko , Slagman Simen‐Jan , Bijlsma Jetta J. E. , Martins dos Santos Vitor A. P. , Suarez‐Diez Maria , Schaap Peter J. 
Published: June 2017

ABSTRACTMycoplasma hyopneumoniae is cultured on large‐scale to produce antigen for inactivated whole‐cell vaccines against respiratory disease in pigs. However, the fastidious nutrient requirements of this minimal bacterium and the low growth rate make it challenging to reach sufficient biomass yield for antigen production. In this study, we sequenced the genome of M. hyopneumoniae strain 11 and constructed a high quality constraint‐based genome‐scale metabolic model of 284 chemical reactions and 298 metabolites. We validated the model with time‐series data of duplicate fermentation cultures to aim for an integrated model describing the dynamic profiles measured in fermentations. The model predicted that 84% of cellular energy in a standard M. hyopneumoniae cultivation was used for non‐growth associated maintenance and only 16% of cellular energy was used for growth and growth associated maintenance. Following a cycle of model‐driven experimentation in dedicated fermentation experiments, we were able to increase the fraction of cellular energy used for growth through pyruvate addition to the medium. This increase in turn led to an increase in growth rate and a 2.3 times increase in the total biomass concentration reached after 3–4 days of fermentation, enhancing the productivity of the overall process. The model presented provides a solid basis to understand and further improve M. hyopneumoniae fermentation processes. Biotechnol. Bioeng. 2017;114: 2339–2347. © 2017 The Authors. Biotechnology and Bioengineering published by Wiley Periodicals, Inc.
A novel free ammonia based pretreatment technology to enhance anaerobic methane production from primary sludge
Authors: Wei Wei , Zhou Xu , Xie Guo‐Jun , Duan Haoran , Wang Qilin 
Published: June 2017

ABSTRACTThis study proposed a novel free ammonia (FA, i.e., NH3) pretreatment technology to enhance anaerobic methane production from primary sludge for the first time. The solubilization of primary sludge was substantially enhanced following 24 h FA pretreatment (250–680 mg NH3‐N/L), by which the release of soluble chemical oxygen demand (SCOD) (i.e., 0.4 mg SCOD/mg VS added; VS: volatile solids) was approximately 10 times as much as that without pretreatment (i.e., 0.03 mg SCOD/mg VS added). Then, biochemical methane potential (BMP) tests demonstrated that FA pretreatment of 250–680 mg NH3‐N/L was capable of enhancing anaerobic methane production while the digestion time was more than 7 days. Model based analysis indicated that the improved anaerobic methane production was due to an increased biochemical methane potential (B0) of 8–17% (i.e., from 331 to 357–387 L CH4/kg VS added), with the highest B0 achieved at 420 mg NH3‐N/L pretreatment. However, FA pretreatment of 250–680 mg NH3‐N/L decreased hydrolysis rate (k) by 24–38% compared with control (i.e., from 0.29 d−1 to 0.18–0.22 d−1), which explained the lower methane production over the first 7 days’ digestion period. Economic analysis and environmental evaluation demonstrated that FA pretreatment technology was environmentally friendly and economically favorable. Biotechnol. Bioeng. 2017;114: 2245–2252. © 2017 Wiley Periodicals, Inc.
A profile of auditory‐responsive neurons in the larval zebrafish brain
Authors: Vanwalleghem Gilles , Heap Lucy A. , Scott Ethan K. 
Published: June 2017

AbstractMany features of auditory processing are conserved among vertebrates, but the degree to which these pathways are established at early stages is not well explored. In this study, we have observed single cell activity throughout the brains of larval zebrafish with the goal of identifying the cellular responses, brain regions, and brain‐wide pathways through which these larvae perceive and process auditory stimuli. Using GCaMP and selective plane illumination microscopy, we find strong responses to auditory tones ranging from 100 Hz to 400 Hz. We also identify different categories of auditory neuron with distinct frequency response profiles. Auditory responses occur in the medial octavolateral nucleus, the torus semicircularis, the medial hindbrain, and the thalamus, and the flow of information among these regions resembles the pathways described in adult fish and mammals. The details of these patterns, however, indicate that auditory processing is still rudimentary in larvae. The range of frequencies detected is small, and while different neurons have distinct response profiles, most are sensitive to multiple frequencies, and distinct categories show substantial overlap in their responses. Likewise, while there are signs of nascent spatial representations of frequency in the larval brain, this only faintly resembles the clear tonotopy seen in adult fish and mammals. Overall, our results show that many fundamental properties of the auditory system are established early in development, and suggest that zebrafish will provide a good model in which to study the development and refinement of these pathways.
Impact of spectral power distribution of daylight simulators on whiteness specification for surface colors
Authors: Wei Minchen , Chen Siyuan 
Published: June 2017

AbstractThe impact of spectral power distribution of daylight simulators (ie, D65 simulators) on surface whiteness specification was investigated by focusing on how CIE whiteness and tint values of 8 whiteness samples with fluorescent whitening agents (FWAs) vary under different D65 simulators. Large variations in both whiteness (∼16 points) and tint (∼1.6 points) are observed under the D65 simulators above BB grade, as characterized using the CIE metamerism index. However, it is found the variations of the whiteness and tint values are smaller under the D65 simulators whose radiant power in the UVA band (ie, 300‐340 nm) was within ±30% in comparison to CIE standard D65 illuminant, as defined in BS 950, which may be a better alternative for evaluating the quality of a D65 simulator for surface white specification using CIE whiteness and tint formulas. The findings also suggest the necessity to fine‐tune or revise the CIE whiteness and tint formulas to characterize the surface whiteness under nonperfect D65 simulators or arbitrary light sources.
Scale‐dependent effects of post‐fire canopy cover on snowpack depth in montane coniferous forests
Authors: Stevens Jens T. 
Published: June 2017

AbstractWinter snowpack in dry montane regions provides a valuable ecosystem service by storing water into the growing season. Wildfire in coniferous montane forests has the potential to indirectly affect snowpack accumulation and ablation (mass loss) rates by reducing canopy cover, which reduces canopy interception of snow but also increases solar radiation and wind speed. These counteracting effects create uncertainty regarding the canopy conditions that maximize post‐fire snowpack duration, which is of concern as montane regions across the western United States experience increasingly warm, dry winters with below‐average snowpack. The net effect of wildfire on snowpack depth and duration across the landscape is uncertain, and likely scale dependent. In this study, I tested whether intermediate levels of wildfire severity maximize snowpack depth by increasing accumulation while slowing ablation, using gridded, repeated snow depth measurements from three fires in the Sierra Nevada of California. Increasing fire severity had a strong negative effect on snowpack depth, suggesting that increased ablation after fire, rather than increased accumulation, was the dominant control over snowpack duration. Contrary to expectations, the unburned forest condition had the highest overall snowpack depth, and mean snow depth among all site visits was reduced by 78% from unburned forest to high‐severity fire. However, at the individual tree scale, snowpack depth was greater under canopy openings than underneath canopy, controlling for effects of fire severity and aspect. This apparent paradox in snowpack response to fire at the stand vs. individual tree scales is likely due to greater variation in canopy cover within unburned and very low severity areas, which creates smaller areas for snow accumulation while reducing ablation via shading. Management efforts to maximize snowpack duration in montane forests should focus on retaining fine‐scale heterogeneity in forest structure.
An empirical examination of consumer effects across twenty degrees of latitude
Authors: Lavender James T. , Dafforn Katherine A. , Bishop Melanie J. , Johnston Emma L. 
Published: June 2017

AbstractThe strength and importance of consumer effects are predicted to increase toward low latitudes, but this hypothesis has rarely been tested using a spatially consistent methodology. In a consumer‐exclusion experiment spanning twenty degrees of latitude along the east Australian coast, the magnitude of consumer effects on sub‐tidal sessile assemblage composition was not greater at low than high latitudes. Across caged and control assemblages, Shannon's diversity, Pielou's evenness, and richness of functional groups decreased with increasing latitude, but the magnitude of consumer effects on these metrics did not display consistent latitudinal gradients. Instead, latitudinal gradients in consumer effects were apparent for individual functional groups. Solitary ascidians displayed the pattern consistent with predictions of greater direct effects of predators at low than high latitude. As consumers reduced the biomass of this and other competitive dominants, groups less prone to predation (e.g., hydroids, various groups of bryozoans) were able to take advantage of freed space in the presence of consumers and show increased abundances there. This large‐scale empirical study demonstrates the complexity of species interactions, and the failure of assemblage‐level metrics to adequately capture consumer effects over large spatial gradients.
Gender differences in colorectal cancer survival: A meta‐analysis
Authors: Yang Yafan , Wang Guiying , He Jingli , Ren Shuguang , Wu Fengpeng , Zhang Jianfeng , Wang Feifei 
Published: June 2017

A meta‐analysis was conducted to determine the influence of gender on overall survival (OS) and cancer‐specific survival (CSS) in colorectal cancer patients. Major databases were searched for clinical trials, which compare survival differences between male and female for colorectal cancer patients. A list of these studies and references, published in English and Chinese from 1960 to 2017, was obtained independently by two reviewers from databases such as PubMed, Medline, ScienceDirect, the China National Knowledge Infrastructure (CNKI) and Web of Science. Overall survival and cancer‐specific survival were compared using Review Manager 5.3. Females had significantly better OS (hazard ratio [HR] = 0.87; 95% confidence interval [CI] = 0.85–0.89) and CSS (HR = 0.92; 95% CI = 0.89–0.95) than males after meta‐analysis. These results suggest that gender seems to be a significant factor influencing survival results among colorectal cancer patients.
A novel versatile precursor suitable for 18F‐radiolabeling via “click chemistry”
Authors: Lugato B. , Stucchi S. , Ciceri S. , Iannone M.N. , Turolla E.A. , Giuliano L. , Chinello C. , Todde S. , Ferraboschi P. 
Published: June 2017

As an effort to improve 18F‐radiolabeling of biomolecules in method robustness and versatility, we report the synthesis and radiolabeling of a new azido precursor potentially useful for the so‐called “click reaction,” in particular the ligand‐free version of the copper(I)‐catalyzed alkyne‐azide cycloaddition. The new azido precursor may help to overcome problems sometimes exhibited by most of the currently used analogues, as it is safe to handle and it displays long‐term chemical stability, thus facilitating the development of new radiolabeling procedures. Moreover, the formed 18F‐labeled 1,2,3‐triazole is potentially metabolically stable and could enhance the in vivo circulation time. The above azido precursor was successfully radiolabeled with 18F, with 51% radiochemical yield (nondecay‐corrected). As a proof of concept, the 18F‐labeled azide was then tested with a suitable alkyne functionalized aminoacid (l‐propargylglycine), showing 94% of conversion, and a final radiochemical yield of 27% (>99% radiochemical purity), nondecay‐corrected, with a total preparation time of 104 minutes.