bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of slurry/clean fluid boundary dispersion during placement of particulate suspension into a fracture
Authors: Reza Md. Omar , Nikrityuk Petr , Eskin Dmitry 
Published: July 2018

AbstractThe main objective of this work is to understand the major peculiarities of the process of clean fracturing fluid being displaced by a flow of particulate suspension (slurry) in a fracture channel. A number of 2D and 3D numerical simulations (based on an Euler‐Euler type model) of slurry flows in channels of complex geometry are carried out. The performance of the model is validated against experimental data by Gillies et al. Euler‐Euler simulations of a laminar slurry flow in a horizontal pipeline showed good agreement between computed and measured particle concentration distributions across a pipe. Numerical studies of slurry flows in 2D and 3D channels show the formation of an M‐shape profile of the solid phase across a channel at the initial fracture section. Our computations demonstrate the rapid growth of a dispersion zone separating a slurry and a clean fluid. It is shown that the dispersion zone is shorter in a tortuous channel than in a straight one. The computations illustrate a reduction in the dispersion zone length with an increase in the fracturing fluid viscosity. The results obtained show the importance of taking into account the previously ignored process of slurry/clean fluid boundary dispersion in prospective hydraulic fracturing simulators.
A fault detection method based on horizontal visibility graph‐integrated complex networks: Application to complex chemical processes
Authors: Geng Zhiqiang , Wang Zun , Hu Haixia , Han Yongming , Lin Xiaoyong , Zhong Yanhua 
Published: July 2018

AbstractWith the trend towards large‐scale structure and complexity in modern chemical processes, it is difficult to describe the system operating status and fault conditions via traditional approaches. In addition, there are obstacles to fault detection research in complex chemical processes due to the characteristics of the equipment hardware used in chemical systems, data collection and handling, strong internal correlations in chemical systems, factors affecting transmission, and randomness and cascade in process failures. Therefore, this paper presents a fault detection method based on horizontal visibility graph (HVG) analysis‐integrated complex networks. The data for each variable in the system are regarded as a time series, each time series is modelled into a network by the horizontal visibility algorithm, and each single‐layer network corresponding to a time series is abstracted as a node. Meanwhile, the correlation between two single‐layer networks is used to characterize the correlation between the corresponding nodes. Moreover, a complex network structure representing the chemical system can be constructed from the correlations. In addition, according to the correlation ratio matrix obtained from the fault state and the normal state, the variance of each node determines the faulty node. Finally, we verify the validity and the effectiveness of the proposed method by applying it to the Tennessee Eastman (TE) process.
The Light‐Driven Isomerization of Aqueous Nitrate: A Theoretical Perspective
Authors: Mewes Jan‐Michael , Jerabek Paul , Bohle D. Scott , Schwerdtfeger Peter 
Published: July 2018

AbstractThe front cover artwork is provided by the CTCP group at Massey University. The image shows the potential energy hypersurface for the NO3− to ONOO− rearrangement. The water and shining light symbolize the photochemical process in aqueous solution. Read the full text of the Article at10.1002/cptc.201800022.
Highly Efficient Base‐Free Dehydrogenation of Formic Acid at Low Temperature
Authors: Prichatz Christoph , Trincado Monica , Tan Lilin , Casas Fernando , Kammer Anja , Junge Henrik , Beller Matthias , Grützmacher Hansjörg 
Published: July 2018

AbstractThe ruthenium complex [RuH2(PPh3)4] is a competent catalyst for the selective dehydrogenation of formic acid (FA) at low temperature. It tolerates water and shows excellent performance (TOF up to 36 000 h−1 at 60 °C). Remarkably, no basic additives are necessary to obtain such high activity and the defined complex is stable for up to 120 days, making this system one of the most effective formic acid dehydrogenation catalysts known to date.
Riverine regime shifts through reservoir dams reveal options for ecological management
Authors: Meißner T. , Schütt M. , Sures B. , Feld C. K. 
Published: July 2018

AbstractWorldwide, dams are a main threat reducing river ecological functioning and biodiversity by severely altering water temperature, flow, and sediment regimes up‐ and downstream. Sustainable dam management therefore has a key role in achieving ecological targets. Here, we present an analysis of the effects of reservoir dams and resulting regime shifts on community structure and function of lotic macroinvertebrates. Our study derived management options to improve ecological integrity of affected streams. To do this, we contrasted time series data for water temperature (15‐min intervals over one year), discharge (daily means over 10 yr), and records of deposited fine sediments against macroinvertebrate samples from pairs of river reaches downstream of dams and of comparable tributaries not affected by dams in the German low mountain range. We observed a decline in the density and diversity of disturbance‐sensitive macroinvertebrates (Ephemeroptera, Plecoptera, and Trichoptera) and a correlation between hydrologic metrics and macroinvertebrate deterioration downstream of the dams. Typical “rhithral” (flow‐adapted) species changed to “littoral” (flow‐avoiding) species below dams, thus indicating a hydrologic regime shift. Increased fine sediment accumulations and deficits of pebbles and small cobbles below dams indicated a severe habitat loss below dams. Additional comparison with undisturbed reference streams allowed us to derive management options that could mitigate the negative impact of hydrologic alterations and accumulations of fine sediments downstream of dams. These options are conditional on the season and in particular address the frequency and duration of low and high flow events.
Impact of lake‐catchment processes on phytoplankton community structure in temperate shallow lakes
Authors: Toporowska Magdalena , Ferencz Beata , Dawidek Jarosław 
Published: July 2018

AbstractResearch on lake‐catchment and biological processes is still innovative. Few reports on this topic exist in the scientific literature. This paper presents species richness, diversity, biomass composition of phytoplankton, and occurrence of cyanobacterial blooms in relation to complex lake‐catchment processes in four shallow lakes. The results revealed that phytoplankton species richness increased with increasing lake trophic state, whereas the opposite relationship was observed for phytoplankton biodiversity. In less eutrophic and deeper lakes, the majority of dominant taxa were representatives of mixed, meso to eutrophic small‐ and medium‐sized lakes. In highly eutrophic lakes, the dominant taxa were common representatives of shallow, very rich in nutrients, turbid, mix layers, and eu‐hypertrophic environments. Redundancy analysis showed that lake depth, flushing time, and conductivity were the most significant factors for phytoplankton development and composition. The hypertrophic, polimictic, and flow‐through Lake Syczyńskie was the most dynamic ecosystem among the lakes. Water mixing and high concentrations of P‐PO4 were beneficial for heavy blooms of the cyanobacterium Planktothrix agardhii observed in Lake Syczyńskie despite the high rate of water exchange. Contrary to the findings of some previous studies, P. agardhii seems to be resistant to flushing at very high loads and concentrations of nutrients (mostly of P‐PO4 and N‐NO3). Phytoplankton assemblages reflected the lakes' habitats, trophic status, and lake‐catchment processes and revealed complex factors that influenced the lakes' functioning. The use of phytoplankton as an indicator of lake‐catchment processes may help understand ecosystem dynamics, essential for the proper selection of management practices protecting aquatic systems against eutrophication.
Vestiges of older greenstone in Mesoarchaean Chakradharpur granite gneiss, Singhbhum Craton, India: Implications for plume‐lithosphere interaction at rifted cratonic margin
Authors: Ghose Naresh C. , Saha Abhishek 
Published: July 2018

The Chakradharpur granite gneiss (CGG) represents an uplifted Archaean basement within the North Singhbhum Orogen (NSO) of Singhbhum‐Orissa Craton in the eastern Indian shield and shares a Mesoarchaean 3.12 Ga age equivalent to the emplacement of Singhbhum granite (SBG) phase III. The CGG hosts numerous enclaves of tonalitic gneisses, metamorphosed ultramafic and mafic volcanics, metagabbros, metasediments, and conglomerates that collectively represent vestiges of an older greenstone belt preserved within it. The mineralogical composition of the ultramafic volcanic enclaves of CGG has been overprinted by greenschist facies metamorphism presenting a talc‐tremolite‐phlogopite‐actinolite assemblage with prominent development of crenulation cleavage, pressure solutions and relict spinifex texture. These are characterised by restricted low SiO2 (39.7–46.8 wt.%) at consistently high MgO (20.7–28 wt.%) contents, and geochemically classified as: (a) subalkaline (Na2O + K2O < 2) komatiite and meimechite and (b) an alkaline (Na2O + K2O > 2) type picrobasalt‐foidite‐basanite assemblage. Depleted LILE and LREE chemistry, Al2O3/TiO2 versus (Gd/Yb)N and HFSE abundances suggest that the studied Al‐undepleted Munro‐type komatiite and meimechite were derived by high degree (30%–50%), shallow level (<90 km) partial melting of a hot, anhydrous mantle plume carrying depleted components. It is suggested that the komatiite‐meimechite melts were deflected by an Archaean cratonic keel and erupted through thinned continental lithosphere at a rifted cratonic margin. Geochemical evidence of crustal contamination preserved in these komatiites are equated with minor input from reworking of older continental materials and interaction between plume‐derived asthenospheric melts and metasomatized subcontinental lithospheric mantle (SCLM). Zr/Hf, Zr/Sm, Nb/Ta, Zr/Nb, and Nb/Th ratios for the picrobasalt, high Mg basalt, foidite and basanite rocks corroborate their generation through variable degrees of partial melting of a heterogeneous lithospheric mantle source carrying depleted plume‐derived melts and enriched components from metasomatized lithosphere. Mantle processes involved assimilation of metasomatic components of SCLM by ascending melts of plume incubating at the base of lithosphere ensued by melt generation at different mantle depths extending from garnet to spinel peridotite domains. Therefore, the geochemical signatures of ultramafic enclaves in CGG invoke distinct magmatic episodes during plume‐craton interaction, melt generation at thinned craton margin to rifted continental interior and melting of metasomatized continental lithosphere that collectively contributed to the evolution of Archaean mantle lithosphere system, volcanism with diverse chemical compositions and greenstone generation in the Singhbhum Craton.
Altered white matter microstructure mediates the relationship between hemoglobin levels and cognitive control deficits in end‐stage renal disease patients
Authors: Mu Junya , Chen Tao , Li Peng , Ding Dun , Ma Xueying , Zhang Ming , Liu Jixin 
Published: July 2018

AbstractThe brain–kidney crosstalk theory suggested that the brain and kidneys may be considered end organs on parallel trajectories and subject to shared risk factors, which are receiving increasing attention. Cognitive control deficits were frequently presented in patients with end‐stage renal disease (ESRD). Whether or not cognitive control impairment is concerned with brain–kidney crosstalk is in need of further research. To detect the relationship between ESRD and cognitive control impairment, diffusion tensor imaging was collected in 64 healthy controls (HCs) and 64 patients with ESRD. Tract‐based spatial statistics and fixel‐based analysis were used to detect the difference of white matter (WM) microstructure and morphology between ESRD patients and HCs in the whole brain. Tractography atlas‐based analysis was also used to investigate the difference of diffusional characteristics along fiber bundles of interest between the two groups. For the whole‐brain analysis, ESRD patients showed WM microstructural alteration and fiber density variation in the cingulum. In addition, ESRD patients exhibited higher MD and RD than HCs along the anterior cingulum. Among all of the blood biochemistry tests that represent kidney disease to a degree, the stepwise regression analysis showed that only hemoglobin significantly contributed to the cognitive control deficits in ESRD patients. Mediation analysis proved that the relationship between hemoglobin and cognitive control deficits of ESRD patients was mediated by WM microstructural alteration of the cingulum. Our results indicated that the anterior cingulum was correlated with cognitive control deficits and mediated the impact of hemoglobin on cognitive control.
Does size affect the relation between option compensation and managerial risk taking? Evidence from Canadian listed companies
Authors: Chakraborty Atreya , Gao Lucia Silva , Sheikh Shahbaz 
Published: July 2018

AbstractWe examine the effect of CEO option compensation on firm risk in Canadian firms listed on the S&P/TSX index. Results show that there is a robust size effect. Option compensation has a positive and significant effect on firm risk only in small firms and no significant effect in large firms. Moreover, option compensation has no significant effect on firm risk in cross‐listed firms, but within the sample of cross‐listed firms option compensation has a positive and significant effect in small firms only. Overall, our results suggest that CEO compensation is more effective in encouraging risk taking in small Canadian firms.
Identification of optimized rod shapes to guide anatomical spinal reconstruction for adolescent thoracic idiopathic scoliosis
Authors: Kokabu Terufumi , Kanai Satoshi , Abe Yuichiro , Iwasaki Norimasa , Sudo Hideki 
Published: July 2018

ABSTRACTAdolescent idiopathic scoliosis (AIS), the most common pediatric musculoskeletal disorder, causes a three‐dimensional deformity of the spine. Although rod curvature could play an important role in anatomical spinal reconstruction in patients with thoracic AIS, intraoperative contouring of the straight rod induces notches into the rod, leading to decreased fatigue strength. Here, we analyzed pre‐bent rod geometries from 46 intraoperative tracings of the rod geometry, which can provide anatomical spinal reconstruction in patients with thoracic AIS. The center point clouds of the rod shapes were extracted and approximated as arcs and straight lines. The difference between the center point clouds were evaluated using the iterative closest point methods. When the rod shapes were divided into six groups based on length followed by hierarchical cluster analysis, 10 representative rod shapes were obtained with a difference value of 5 mm. Thus, we identified optimized rod shapes to guide anatomical spinal reconstruction for thoracic AIS, which will reduce not only the risk of rod breakage but also operation time, leading to decreased patient burden. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:3219–3224, 2018.
Cover Image, Volume 98, Issue 12
Authors: Yan Jia‐wei , Ban Zhao‐jun , Lu Hong‐yan , Li Dong , Poverenov Elena , Luo Zi‐sheng , Li Li 
Published: July 2018

The cover image, by Jia‐wei Yan et al., is based on the Review The aroma volatile repertoire in strawberry fruit: a review, DOI: 10.1002/jsfa.9039.
image
“Single‐pot” approach towards the preparation of alkyl and polyfluoroalkyl organo‐silica monolithic capillaries for reversed‐phase liquid chromatography
Authors: Narciso Meirelles Lucas , Silva Campos Thales , Rodriguez Zulema , Hernandez Rebecca , Svec Frantisek , Zajickova Zuzana 
Published: July 2018

AbstractOrgano‐silica monolithic capillary columns were prepared using thermally initiated polymerization of mixtures containing 3‐(methacryloyloxy)propyltrimethoxysilane as the silicon‐containing monomer, an aqueous acid catalyst, ethylene dimethacrylate as the cross‐linker, a functional monomer selected from the group comprising octadecyl methacrylate, trifluoroethyl methacrylate, pentafluoropropyl methacrylate, and heptadecafluorodecyl methacrylate, toluene as the porogen, and 2,2′‐azobisisobutyronitrile as the initiator. The permeability of the monoliths was controlled by varying the composition of the polymerization mixture. Chromatographic properties of resulting monolithic 100 μm i.d. capillaries were evaluated utilizing four sets of probe compounds under isocratic elution conditions in the reversed‐phase mode. Baseline separation of alkylbenzenes and the best steric selectivity were achieved using the octadecyl methacrylate monolithic column verifying that its surface was the most hydrophobic. In contrast, separation of a mixture containing polar compounds was observed using columns prepared in the absence of the functional monomer due to the presence of residual surface silanols at the pore surface. Polyfluoroalkyl stationary phases, especially those with a high number of fluorine atoms, exhibited the highest selectivity towards fluorine‐containing analytes.
Synthesis and Characterization of Shell‐Cross‐Linked Glycopolymer Bilayer Vesicles
Authors: Nishimura Tomoki , Toh Wei‐Lun , Akiyoshi Kazunari 
Published: July 2018

AbstractVesicles composed of self‐assembled lipids or amphiphilic polymers have significant potential in applications such as delivery of cargo for therapeutics. However, they are fragile under physiological conditions such as inside living cells or the bloodstream, in which a vast number of other molecules are present in high concentrations. This is because vesicles are in dynamic equilibrium between unimers and vesicles. Therefore, the development of more robust vesicles by covalent cross‐linking of the shell was focused on. Cross‐linked polymer vesicles were prepared by the self‐assembly of maltopentaose‐b‐poly(propylene glycol) followed by the reaction between divinyl sulfone and the hydroxyl group in a maltopentaose unit. It was found that two equivalents of DVS to the polymer is an optimal condition for the cross‐linking without changing in size. The bilayer structures were retained after the cross‐linking reactions. Importantly, the cross‐linked polymer vesicles retained their size and polydispersity even in 50:50 v/v methanol/water solution. This work highlights the potential of the divinyl sulfone shell cross‐link as a promising tool for stabilization of glycopolymer vesicles.
Atom Transfer Radical Polymerization (ATRP) Catalyzed by Visible Light‐Absorbed Small Molecule Organic Semiconductors
Authors: Wang Lei , Li Run , Zhang Kai. A.I. 
Published: July 2018

AbstractAtom transfer radical polymerization is successfully conducted with an organic semiconductor (OS)‐based visible light activated photocatalyst via a precisely designed catalytic cycle. The living nature of the polymerization by the OS type photocatalyst is proved by the linearly‐increasing molecular weight with consumption of the monomer, the expected molecular weight from MALDI‐TOF measurements, and the chain extending reaction, as well as block copolymer synthesis. Benefitting from clear and measurable reductive potential as well as the oxidative potential of the OS‐type photocatalyst, the intrinsic demand for “living radical polymerization” is discussed and examined, which indicates the diversity and great potential of OS‐type photocatalysts for organic synthesis.
Nickel exposure reduces enterobactin production in Escherichia coli
Authors: Washington – Hughes Clorissa L. , Ford Geoffrey T. , Jones Alsten D. , McRae Kimberly , Outten F. Wayne 
Published: July 2018

AbstractEscherichia coli is a well‐studied bacterium that can be found in many niches, such as industrial wastewater, where the concentration of nickel can rise to low‐millimolar levels. Recent studies show that nickel exposure can repress pyochelin or induce pyoverdine siderophore production in Pseudomonas aueroginosa. Understanding the molecular cross‐talk between siderophore production, metal homeostasis, and metal toxicity in microorganisms is critical for designing bioremediation strategies for metal‐contaminated sites. Here, we show that high‐nickel exposure prolongs lag phase duration as a result of low‐intracellular iron levels in E. coli. Although E. coli cells respond to low‐intracellular iron during nickel stress by maintaining high expression of iron uptake systems such as fepA, the demand for iron is not met due to a lack of siderophores in the extracellular medium during nickel stress. Taken together, these results indicate that nickel inhibits iron accumulation in E. coli by reducing the presence of enterobactin in the extracellular medium.
A new approach to design asymptotically stabilizing control and adaptive control
Authors: Noori Skandari Mohammad Hadi , Nazemi Alireza 
Published: July 2018

SummaryIn this paper, we propose a new approach to design the asymptotically stabilizing control and adaptive control for nonlinear systems. We first propose an infinite‐horizon optimal control (OC) problem according to the nonlinear control system. We prove that its OC can be an asymptotically stabilizing control or adaptive control for the original nonlinear system. Then, we convert the infinite‐horizon OC problem into an equivalent finite‐horizon OC problem. Moreover, we utilize the Legendre pseudospectral method to solve the proposed problem. Finally, several examples are given to illustrate the efficiency of the approach.
Dimensional impact of nanofillers on the micromorphology and rheology of PP/PS composites under continuous elongation flow
Authors: Zhang Xiao‐qiu , Tan Yong‐bin , Chen Rong‐yuan , Zhang Gui‐zhen , Qu Jin‐ping 
Published: July 2018

Three kinds of nanoscaled fillers, namely, zero‐dimensional nanosphere titanium dioxide (TiO2), one‐dimensional multi‐walled carbon nanotubes (MWCNTs), and two‐dimensional nanoplate montmorillonite (MMT), were added to the representative polypropylene (PP)/polystyrene (PS) blends by eccentric rotor extruder based on elongation flow. Confirmed from images of transmission electron microscopy and scanning electron microscopy, three kinds of nanofillers were uniformly dispersed in the blends under continuous elongation flow and the presence of nanofillers led to a marked decrease of dispersed phase size of PS. The dispersed PS particles were turned into spherical status in matrix with the addition of TiO2 and MWCNTs and showed irregular shapes in the composites with MMT. The PS particle size of PP/PS/MMT was decreased most obviously, dropping from 4.44 to 1.42 μm, which resulted in obvious improvements in storage modulus and complex viscosity of the composites. The results of wide‐angle X‐ray diffraction and dynamic mechanical analysis indicated that MMT nanoparticles were highly intercalated in PP/PS blends, which obviously improved compatibility of PP and PS. Our work certified that the two‐dimensional nanoplate MMT are better compatibilizers compared with the zero‐dimensional nanosphere TiO2 and one‐dimensional MWCNTs for PP/PS composites.