bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of height of flotation column on flow field
Authors: Su Wenbing , Yan Xiaokang , Wang Lijun , Zhang Haijun , Cao Yijun 
Published: May 2019

AbstractCyclonic‐static microbubble flotation column (FCSMC) is a sorting equipment for micro fine‐grained minerals. The column height is an important factor affecting the flotation efficiency, which will directly affect the flow field and separation performance. In this study, particle image velocimetry measurement on single phase of lab‐scale FCSMC with diameter D of 0.1 m was tested to verify the accuracy of the turbulent model used in computational fluid dynamics simulation. Then the FCSMC with different upper column and lower column height were simulated and analyzed. Results show that the axial velocity and tangential velocity play a major role in FCSMC. With the increasing of the upper column height, both tangential velocity and centrifugal intensity decrease, which help to get a static environment for column flotation unit. But too high upper column height will affect the separation of the cyclone flotation unit due to small centrifugal intensity. When the lower column height‐to‐diameter ratio H2/D increases from 1 to 4, it has no obvious effect on column flotation unit, but does effect on the flow field of the cyclone flotation unit. As the lower column height increases, the upward overflow is more prominent and the region becomes larger. Peculiarly, tangential velocity is large under too small lower column height, like H2/D = 1, but is bad for the separation of large size tailings due to low distance and great suction. Within the scope of this study, the lower column height range is more suitable for H2/D = 2–3.
Reinforced properties of polybenzoxazine‐based nanocomposites with siloxane benzoxazine‐modified halloysite nanotubes
Authors: Li Jing , Shen Zhiqiang , Li Huanxin , Xu Li , Song Huaijun , Guan Gang , Liu Guoji 
Published: May 2019

ABSTRACTSiloxane benzoxazine monomer (Ba‐s) was synthesized using phenol, 3‐aminopropyltriethoxysilane (KH‐550), and paraformaldehyde, and then introduced onto halloysite nanotubes (HNTs) surface as a coupling agent to obtain functionalized HNTs (mHNTs). 1, 6‐hexanediamine/phenol benzoxazine (Ba‐h) was selected as a matrix to blend with mHNTs at the mass ratios of 1:0, 9:1, 7:1, 6:1, 4:1,7:3, and 3:2, respectively. The ring‐opening copolymerization behaviors of the nanocomposites were investigated by differential scanning calorimetry. The results implied that the polymerization temperature of Ba‐h was decreased by the grafted HNTs. The results of thermogravimetric analysis and dynamic mechanical analysis displayed that the obtained copolymers exhibit different degrees of improvement in the thermal stability and mechanical properties of Ba‐h. These enhancements are attributed to the homogeneous dispersion of HNTs and the strong matrix‐nanoparticle interactions based on SEM and TEM results. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47882.
High‐density polyethylene membranes embedded with carboxylated and polyethylene glycol‐grafted nanodiamond to be used in membrane bioreactors
Authors: Kivi Masoud Azimian , Alinia Hossein , Jafarzadeh Yoones , Yegani Reza 
Published: May 2019

ABSTRACTIn this work, neat and modified nanodiamond (ND) particles were embedded into high‐density polyethylene (HDPE) membranes to improve hydrophilicity and antifouling properties. The membranes were prepared via thermally induced phase separation (TIPS) method and used for pharmaceutical wastewater treatment in membrane bioreactors (MBR) system. To prevent the agglomeration of ND, it was modified using two methods: thermal carboxylation (ND‐COOH) and grafting with polyethylene glycol (ND‐PEG). Membranes with different concentration of ND‐COOH and ND‐PEG nanoparticles ranging from 0.00 to 1.00 wt % were prepared and characterized using a set of analyses including water contact angle, pure water flux, tensile strength, differential scanning calorimeter, field emission scanning electron microscopy, and energy dispersive X‐ray spectroscopy. It was found that the optimum contents of ND‐COOH and ND‐PEG nanoparticles were 0.50 wt % and 0.75 wt %, respectively. The interfacial interaction between nanoparticles and HDPE matrix was studied based on Pukanzsky model. To examine the performance of membranes, critical flux, filtration experiment in the MBR, and fouling analysis of membranes were carried out. The results showed that among the fabricated membranes, 0.75 wt % HDPE/ND‐PEG membrane had the highest water flux and the best antifouling properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47914.
Enantioselective synthesis and biological investigation of tetrahydro‐β‐carboline‐based HDAC6 inhibitors with improved solubility
Authors: Grünstein Elisabeth , Sellmer Andreas , Mahboobi Siavosh 
Published: May 2019

AbstractAberrant epigenetic changes in DNA methylation and histone modification by acetylation or deacetylation regulate the pathogenesis of many diseases. Especially selective inhibitors are getting more and more attention. We recently reported on a new class of potent and selective anti‐inflammatory and antirheumatic histone deacetylase 6 (HDAC6) inhibitors (e.g., Marbostat‐100). The attachment of a morpholinoethoxy part to the head group dramatically enhances the solubility, in particular the solubility in aqueous solutions, of the lead compound Marbostat‐100. Here, we present the enantioselective synthesis of small‐molecule compounds based on the tetrahydro‐β‐carboline core system with improved solubility, and the influence of the stereochemistry on the biological activity. The enantiomers were synthesized in good enantiomeric excess (ee) purity and were potent and selective HDAC6 inhibitors, whereas theS‐derivativeS‐21is clearly the eutomer. The potency of our selective HDAC6 inhibitors is demonstrated byKivalues in the range of 0.5–2 nM toward HDAC6, and the selectivity was proved in cellular assays by Western blot analysis taking ac‐tubulin as surrogate parameter.
Framing experts' (dis)agreements about uncertain environmental events
Authors: Løhre Erik , Sobkow Agata , Hohle Sigrid Møyner , Teigen Karl Halvor 
Published: May 2019

AbstractAgreements and disagreements between expert statements influence lay people's beliefs. But few studies have examined what is perceived as a disagreement. We report six experiments where people rated agreement between pairs of probabilistic statements about environmental events, attributed to two different experts or to the same expert at two different points in time. The statements differed in frame, by focusing on complementary outcomes (45% probability that smog will have negative health effects vs. 55% probability that it will not have such effects), in probability level (45% vs. 55% probability of negative effects), or in both respects. Opposite frames strengthened disagreement when combined with different probability levels. Approximate probabilities can be “framed” in yet another way by indicating reference values they are “over” or “under”. Statements that use different directional verbal terms (over vs. under 50%) indicated greater disagreement than statements with the same directional term but different probability levels (over 50% vs. over 70%). Framing and directional terms similarly affected consistency judgments when both statements were issued by the same expert at different occasions. The effect of framing on perceived agreement was significant for medium (10 and 20 percentage points) differences between probabilities, whereas the effect of directional term was stable for numerical differences up to 40 percentage points. To emphasize agreement between different estimates, they should be framed in the same way. To accentuate disagreements or changes of opinion, opposite framings should be used.
Moisture effects on robustness of sorghum grain protein near‐infrared spectroscopy calibration
Authors: Peiris Kamaranga H. S. , Bean Scott R. , Chiluwal Anuj , Perumal Ramasamy , Jagadish S. V. Krishna 
Published: May 2019

AbstractBackground and objectivesA near‐infrared (NIR) spectroscopy method was developed for rapid and nondestructive evaluation of protein content of intact sorghum grains. Effect of grain sample moisture variation on the robustness of protein calibration was investigated.FindingsAn initial NIR protein calibration model with sorghum grains in 7.28%–11.57% moisture content range with coefficient of determination (R2) of 0.94 and standard error of cross‐validation (SECV) of 0.41%, predicted protein content of an external validation set of different varieties with R2 = 0.90, root‐mean‐square error of prediction (RMSEP) = 0.42% and bias = −0.02%. However, when grains with a wider range of moisture content (7.50%–17.75%) were used for validation, prediction errors increased with R2 = 0.72 RMSEP = 0.87% and bias = −0.32%. Inclusion of grains with a wider moisture range to the calibration set improved the performance of the calibration model with a R2 = 0.83, RMSEP = 0.67% with a bias of −0.04%.ConclusionsVariation of moisture content in grains affected the performance of the NIR protein calibration model. Likewise, inclusion of moisture variation in the calibration sample set improved the robustness of the model.Significance and noveltyIn addition to the traits of interest, variation of other physical or chemical traits should also be considered for inclusion into the calibration sample set to improve the robustness of NIR calibration models. This is especially important when NIR spectroscopy methods are developed for evaluation of breeding populations as the future grain samples from numerous crosses may be substantially diverse.
Molybdenum Selenide Electrocatalysts for Electrochemical Hydrogen Evolution Reaction
Authors: Zhang Kaili , Li Yahao , Deng Shengjue , Shen Shenghui , Zhang Yan , Pan Guoxiang , Xiong Qinqin , Liu Qi , Xia Xinhui , Wang Xiuli , Tu Jiangping 
Published: May 2019

AbstractRational construction and smart modification of cost‐effective and high‐performance electrocatalysts are of great importance for the development of high‐efficiency electrochemical hydrogen evolution reaction (HER). Molybdenum selenide (MoSe2)‐based nanocomposites are considered as one of the most promising electrocatalysts for HER, owing to its superior catalytic activity, long‐term stability, and relatively low cost. In this Review, we summarize the recent progress on MoSe2‐based electrocatalysts for HER including synthesis methods, electrochemical properties and catalytic mechanisms. The mechanism of HER and influencing factors of MoSe2‐based electrocatalysts are briefly reviewed. Additionally, the benefits and the difficulties of different synthetic methods are also summarized. Furthermore, diverse modification strategies to increase electrocatalytic activity of MoSe2 are thoroughly discussed. Finally, the challenges and outlook on the advancement of MoSe2‐based electrocatalysts are presented.
A Generalized Kinetic Framework Applied to Whole‐Cell Bioelectrocatalysis in Bioflow Reactors Clarifies Performance Enhancements for Geobacter Sulfurreducens Biofilms
Authors: Zarabadi Mir Pouyan , Couture Manon , Charette Steve J. , Greener Jesse 
Published: May 2019

AbstractA common kinetic framework for studies of whole‐cell catalysis is vital for understanding and optimizing bioflow reactors. In this work, we demonstrate the applicability of a flow‐adapted version of Michaelis‐Menten kinetics to an electrocatalytic bacterial biofilm. A three‐electrode microfluidic biofilm flow reactor measured increased turnover rates by as much as 50 % from a Geobacter sulfurreducens biofilm as flow rate was varied. Based on parameters from the applied kinetic framework, flow‐induced increases to turnover rate, catalytic efficiency and device reaction capacity could be linked to an increase in catalytic biomass. This study demonstrates that a standardized kinetic framework is critical for quantitative measurements of new living catalytic systems in flow reactors and for benchmarking against well‐studied catalytic systems such as enzymes.
Solution Synthesis of Porous Silicon Particles as an Anode Material for Lithium Ion Batteries
Authors: Wang Fei , Sun Lin , Zi Wenwen , Zhao Baoxun , Du Hongbin 
Published: May 2019

AbstractNanostructured silicon‐based materials with porous structures have recently been found to be impressive anode materials with high capacity and cycling performance for lithium‐ion batteries. However, the current methods of preparing porous silicon have generally been confronted with the requirement for multiple steps and complex synthesis. In the present study, porous silicon with high surface area was prepared by using a high yielding and simple reaction in which commercial magnesium powder readily reacts with HSiCl3 with the help of an amine catalyst under mild conditions. The obtained porous silicon was coated with a nitrogen‐doped carbon layer and used as the anode for lithium‐ion batteries. The porous Si‐carbon nanocomposites exhibited excellent cycling performance with a retained discharge capacity of 1300 mA h g−1 after 200 cycles at 1 A g−1 and a discharge capacity of 750 mA h g−1 at a current density of 2 A g−1 after 250 cycles. Remarkably, the Coulombic efficiency was maintained at nearly 100 % throughout the measurements.
1,4‐Dehydrogenation with a Two‐Coordinate Cyclic (Alkyl)(amino)silylene
Authors: Koike Taichi , Kosai Tomoyuki , Iwamoto Takeaki 
Published: May 2019

AbstractCyclic (alkyl)(amino)silylene (CAASi) 1 has been found to successfully dehydrogenate 1,4‐dihydroaromatic compounds containing various substituents to afford the corresponding aromatic compounds. The observed high substrate generality proves 1 to be a potential 1,4‐dehydrogenation reagent for organic compounds. For the reaction with 9,10‐dimethyl‐9,10‐dihydroanthracene, silylene 1 activated not only benzylic C−H bonds but also aromatic C−H bonds to yield a silaacenaphthene derivative, which is an unprecedented reaction of silylenes. The results of the experimental and computational study of the reaction of CAASi 1 with 9,10‐dihydroanthracene and 1,4‐cyclohexadiene are consistent with the notion that 1,4‐dehydrogenation with CAASi 1 proceeds mainly through a stepwise hydrogen‐abstraction mechanism.
Strategies for the Synthesis of Chiral Carbon‐Bridged Group IV ansa‐Metallocenes
Authors: Bau Michael A. , Wiesler Stefan , Younas Sara L. , Streuff Jan 
Published: May 2019

AbstractThis minireview provides a survey of the various synthetic approaches to chiral ansa‐metallocenes of Ti, Zr, and Hf containing a carbon‐based bridge. The individual strategies to install substitution patterns at either the cyclopentadienyl framework or the bridging unit are highlighted with focus on the progress made towards a direct preparation of single complex stereoisomers. The review further includes the discussion of potential problems such as the formation of undesired diastereomers, the threat of racemization of enantiopure material, and synthetic challenges originating from the synthesis, purification, and isolation of the target complexes. The review has been written with the goal in mind to facilitate the design and synthesis of new chiral ansa‐metallocene derivatives for emerging research areas in asymmetric catalysis and organometallic chemistry.
Laser‐Induced Wurtz‐Type Syntheses with a Metal‐Free Photoredox Catalytic Source of Hydrated Electrons
Authors: Kohlmann Tim , Kerzig Christoph , Goez Martin 
Published: May 2019

AbstractUpon irradiation with ns laser pulses at 355 nm, 2‐aminoanthracene in SDS micelles readily produces hydrated electrons. These “super‐reductants” rapidly attack substrates such as chloro‐organics and convert them into carbon‐centred radicals through dissociative electron transfer. For a catalytic cycle, the aminoanthracene needs to be restored from its photoionization by‐product, the radical cation, by a sacrificial donor. The ascorbate monoanion can only achieve this across the micelle–water interface, but the monoanion of ascorbyl palmitate results in a fully micelle‐contained regenerative electron source. The shielding by the micelle in the latter case not only increases the life of the catalyst but also strongly suppresses the interception of the carbon‐centred radicals by the hydrogen‐donating ascorbate moiety; and in conjunction with the high local concentrations effected by the pulsed laser, termination by radical dimerization thus dominates. We have obtained a complete and consistent picture through monitoring the individual steps and the assembled system by flash photolysis on fast and slow timescales, from microseconds to minutes; and in preparative studies on a variety of substrates, we have achieved up to quantitative dimerization with a turnover on the order of 1 mmol per hour.
A Multifunctional, Charge‐Neutral, Chiral Octahedral M12L12 Cage
Authors: Boer Stephanie A. , White Keith F. , Slater Benjamin , Emerson Adrian J. , Knowles Gregory P. , Donald William A. , Thornton Aaron W. , Ladewig Bradley P. , Bell Toby D. M. , Hill Matthew R. , Chaffee Alan L. , Abrahams Brendan F. , Turner David R. 
Published: May 2019

AbstractA chiral, octahedral M12L12 cage, which is charge neutral and contains an internal void of about 2000 Å3, is reported. The cage was synthesised as an enantiopure complex by virtue of amino‐acid‐based dicarboxylate ligands, which assemble around copper paddlewheels at the vertices of the octahedron. The cage persists in solution with retention of the fluorescence properties of the parent acid. The solid‐state structure contains large pores both within and between the cages, and displays permanent porosity for the sorption of gases with retention of crystallinity. Initial tests show some enantioselectivity of the cage towards guests in solution.
The clinical outcomes of patients who developed typical atrial flutter on class 1C anti arrhythmic medications treated with hybrid approach
Authors: Grossman Lior , Katz Moshe , Beinart Roy , Nof Eyal 
Published: May 2019

IntroductionA common approach to patients, who developed atrial flutter secondary to treatment with class 1C anti‐arrhythmic drugs for atrial fibrillation (AF) (1C flutter), is a hybrid approach: ablation of the Cavo‐Tricuspid isthmus (CTI) and continuation 1C medical treatment to prevent recurrence of AF. We aim to explore the clinical outcome of patients treated in this approach.Methods and ResultsTwo hundred and four consecutive patients who underwent ablation for typical AFL at a tertiary medical center between 2010 and 2016 were enrolled and followed up. The clinical outcome of patient treated by the hybrid approach (treatment group; n = 67) was compared to patient without history of AF (control group; n = 137). The primary endpoint was time to occurrence of AF. Twenty‐eight (41.8%) patients in treatment group had AF occurrence in 1 year, including 9 (13.4%) patients who needed to escalate anti‐arrhythmic drug treatment to class III, and 11 (16.4%) patients who underwent AF ablation. In comparison, only 21 (15.3%) patients in control group had occurrence during the first year after ablation. The median time from ablations till AF occur was 106 ± 481 days in treatment group, and 403 ± 668 days in control group (P < .01).ConclusionsThere is a relatively high rate of AF recurrence in patients treated with the hybrid approach during the first year after CTI ablation. An alternative approach should be considered in this selected population.
Visible‐Light‐Driven Plasmonic Photocatalysis Enhanced by Charge Accumulation
Authors: Kao Kun‐Che , Nishi Hiroyasu , Tatsuma Tetsu 
Published: May 2019

AbstractPlasmon‐induced charge separation (PICS) at the interface between a plasmonic material and semiconductor is employed to drive photocatalytic reactions for conversion and storage of solar energy. Most of the conventional photoelectrodes based on PICS have an n‐M type structure with an interface between n‐type semiconductor (typically TiO2) and plasmonic metal (typically Au) nanoparticles. Here we develop n‐M‐p type photoelectrodes by coating the TiO2/Au photoelectrode with Ni(OH)2 or CrOx, which can collect and store positive charges. Both of the photoelectrodes show efficient PICS under visible light and accumulate positive charges released from resonant Au nanoparticles. The accumulated charges can be used for oxidation of organic species such as ethanol in the dark. The TiO2/AuNP/Ni(OH)2 photoelectrode exhibits an oxygen evolution ability under visible light with a certain bias voltage.
Rendering differential performance preference through intelligent network edge in cloud data centers
Authors: Shen Dian , Zhou Pengcheng , Gao Yidan , Guo Xiaolin , Xiong Runqun 
Published: May 2019

SummarySharing the network infrastructure, the performance of emerging distributed applications and services in data centers is directly impacted by the network. As these applications are becoming more and more demanding, it is challenging to satisfy their requirements of low latency, high throughput, and low packet loss rate simultaneously. Prior approaches typically resort to flow control or scheduling mechanisms, prioritizing flows according to their demands. However, none of the methods can solely satisfy the various demands of data center applications. Addressing this challenge, we propose tasch, a preference aware flow scheduling mechanism equipped in the software network edge (ie, end‐host networking). This mechanism utilizes multiple separate queues for flows with different preferences, which guarantees low packet delay for latency‐sensitive flows and provides bandwidth guarantees for throughput‐sensitive flows. A coordinating algorithm is presented to share the network resource among multiple queues with pareto‐optimality. tasch is implemented as a thin and plugable kernel module in Linux based hypervisors, which lies between the complicated physical network and tenants VMs. Subsequently, based on the flow traces of real‐world applications, extensive experiments were conducted to verify the effectiveness of network management mechanism.
Tracking Conformational Changes in Calmodulin in vitro, in Cell Extract, and in Cells by Electron Paramagnetic Resonance Distance Measurements
Authors: Dalaloyan Arina , Martorana Andrea , Barak Yoav , Gataulin Diana , Reuveny Eitan , Howe Andrew , Elbaum Michael , Albeck Shira , Unger Tamar , Frydman Veronica , Abdelkader Elwy H. , Otting Gottfried , Goldfarb Daniella 
Published: May 2019

AbstractIt is an open question whether the conformations of proteins sampled in dilute solutions are the same as in the cellular environment. Here we address this question by double electron‐electron resonance (DEER) distance measurements with Gd(III) spin labels to probe the conformations of calmodulin (CaM) in vitro, in cell extract, and in human HeLa cells. Using the CaM mutants N53C/T110C and T34C/T117C labeled with maleimide‐DOTA‐Gd(III) in the N‐ and C‐terminal domains, we observed broad and varied interdomain distance distributions. The in vitro distance distributions of apo‐CaM and holo‐CaM in the presence and absence of the IQ target peptide can be described by combinations of closed, open, and collapsed conformations. In cell extract, apo‐ and holo‐CaM bind to target proteins in a similar way as apo‐ and holo‐CaM bind to IQ peptide in vitro. In HeLa cells, however, in the presence or absence of elevated in‐cell Ca2+ levels CaM unexpectedly produced more open conformations and very broad distance distributions indicative of many different interactions with in‐cell components. These results show‐case the importance of in‐cell analyses of protein structures.