bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observation of atomic oxygen O(1S) green‐line emission in the summer polar upper mesosphere associated with high‐energy (≥30 keV) electron precipitation during high‐speed solar wind streams
Authors: Lee Young‐Sook , Kwak Young‐Sil , Kim Kyung‐Chan , Solheim Brian , Lee Regina , Lee Jaejin 
Published: November 2016

AbstractThe auroral green‐line emission at 557.7 nm wavelength as arising from the atomic oxygen O(1S → 1D) transition typically peaks at an altitude of ~100 km specifically in the nightside oval, induced by auroral electrons within an energy range of ~100 eV–30 keV. Intense aurora is known as being suppressed by sunlight in summer daytime but usually occurs in low electrical background conductivity. However, in the present study in summer (July) sunlit condition, enhancements of O(1S) emission rates observed by using the Wind Imaging Interferometer/UARS were frequently observed at low altitudes below 90 km, where ice particles are created initially as subvisible and detected as polar mesosphere summer echoes, emerging to be an optical phenomenon of polar mesospheric clouds. The intense O(1S) emission occurring in summer exceeds those occurring in the daytime in other seasons both in occurrence and in intensity, frequently accompanied by occurrences of supersonic neutral velocity (300–1500 m s−1). In the mesosphere, ion motion is controlled by electric field and the momentum is transferred to neutrals. The intense O(1S) emission is well associated with high‐energy electron precipitation as observed during an event of high‐speed solar wind streams. Meanwhile, since the minimum occurrences of O(1S) emission and supersonic velocity are maintained even in the low precipitation flux, the mechanism responsible is not only related to high‐energy electron precipitation but also presumably to the local conditions, including the composition of meteoric‐charged ice particles and charge separation expected in extremely low temperatures (<150 K).
Nonlinear acoustic waves in the viscous thermosphere and ionosphere above earthquake
Authors: Chum J. , Cabrera M. A. , Mošna Z. , Fagre M. , Baše J. , Fišer J. 
Published: November 2016

AbstractThe nonlinear behavior of acoustic waves and their dissipation in the upper atmosphere is studied on the example of infrasound waves generated by vertical motion of the ground surface during the Mw 8.3 earthquake that occurred about 46 km from Illapel, Chile on 16 September 2015. To conserve energy, the amplitude of infrasound waves initially increased as the waves propagated upward to the rarefied air. When the velocities of air particles became comparable with the local sound speed, the nonlinear effects started to play an important role. Consequently, the shape of waveform changed significantly with increasing height, and the original wave packet transformed to the “N‐shaped” pulse resembling a shock wave. A unique observation by the continuous Doppler sounder at the altitude of about 195 km is in good agreement with full wave numerical simulation that uses as boundary condition the measured vertical motion of the ground surface.
Investigation of the influence of liquid surface films on O3 and PAN deposition to plant leaves coated with organic/inorganic solution
Authors: Sun Shang , Moravek Alexander , Trebs Ivonne , Kesselmeier Jürgen , Sörgel Matthias 
Published: November 2016

AbstractThis study investigates the influence of leaf surface water films on the deposition of ozone (O3) and peroxyacetyl nitrate (PAN) under controlled laboratory conditions. A twin‐cuvette system was used to simulate environmental variables. We observed a clear correlation between the O3 deposition on plants (Quercus ilex) and the relative humidity (RH) under both light and dark conditions. During the light period the observed increase of the O3 deposition was mainly attributed to the opening of leaf stomata, while during the absence of light the liquid surface films were the reason for O3 deposition. This finding was supported by experimentally induced stomatal closure by the infiltration of abscisic acid. In the case of PAN, no relationship with RH was found during the dark period, which indicates that the nonstomatal deposition of PAN is not affected by the liquid surface films. Consequently, the ratio of the O3 and PAN deposition velocities is not constant when relative humidity changes, which is in contrast to assumptions made in many models. The flux partitioning ratio between nonstomatal and stomatal depositions as well as between nonstomatal and total depositions was found to be Rnsto/sto = 0.21–0.40, Rnsto/tot = 0.18–0.30 for O3 and Rnsto/sto = 0.26–0.29, Rnsto/tot = 0.21–0.23 for PAN. Furthermore, we demonstrate that the formation of the liquid surface film on leaves and the nonstomatal O3 deposition are depending on the chemical composition of the particles deposited on the leaf cuticles as proposed previously.
Financial Implications of the Emergency Medicine Interview Process
Authors: Van Dermark Jeffrey Todd , Wald David A. , Corker John Robert , Reid David Godley 
Published: November 2016

AbstractBackgroundEmergency medicine (EM) residency interviews are an important, yet costly process for programs and applicants. The total economic burden of the EM interviewing process is previously unstudied. Graduate medical education funding and student finances are both fragile shifting sources, which appear to fund most of these economic expenditures.ObjectivesThe total economic impact of the EM interview season is unknown. This study sought to calculate total dollars spent by EM residency programs and senior medical students (M4) during interview season. Potential solutions for reducing this burden will be outlined.MethodsInstitutional review board–approved, piloted e‐mail surveys were sent to accredited (Accreditation Council for Graduate Medical Education [ACGME] and American Osteopathic Association [AOA]) EM program directors (PDs) and M4 student members of EMRA. PDs were queried after the 2014–2015 interview season. PDs questions included demographics, estimated faculty, and resident and administrative time used, along with dollars spent during the 2014–2015 interview season. M4 questions included demographics and dollars spent during the 2015–2016 season. Results were reported using descriptive statistics. Financial data for EM programs were calculated with academic EM faculty, resident, and administrative assistant salaries along with reported hours used during the interview season.ResultsA total of 82 of 223 EM PDs completed the survey, reporting an mean annual cost of $210,649.04 per program to review, screen, and interview applicants based on time spent by faculty, resident, and administrative assistants. A total of 84.6% of EM program costs were due to faculty hours. A total of 180 of 1,425 EM‐bound M4 students completed the survey, reporting a mean annual estimate of US$5,065.44 per student to apply and interview. Seventy‐two percent of estimated costs were due to airfare and lodging. Loans and credit cards were the top two methods of payments of these interview costs by students. Extrapolating the cost of EM personnel with hours spent, the economic burden of an interview season for EM programs is approximately US$46,974,735.92. M4 students spent US$19,724,823.40 for application fees and interview‐related expenses.ConclusionsEmergency medicine residency programs and applicants appear to spend over US$66 million per cycle on the interview process. EM residency programs may save resources by reducing faculty hours associated with the interview process and leveraging administrative and resident resources. Creation of regional or national fixed interview locations may also be appropriate. Applicants may reduce travel costs by participating in video interviews, reducing program applications, and attending regionalized interview days. A full conversation among all specialties and organized medicine needs to take place to reform the systems in place to reduce the economic burden on students and residency programs.
Pitfalls in the use of epinephrine for anaphylaxis: patient and provider opportunities for improvement
Authors: Cohen Michael B. , Saunders Stefanie S. , Wise Sarah K. , Nassif Samih , Platt Michael P. 
Published: November 2016

BackgroundEpinephrine remains the mainstay of treatment for life‐threatening allergic reactions. A number of challenges are encountered with epinephrine, resulting in underutilization and misutilization of epinephrine. The purpose of this study was to identify the scope of epinephrine pitfalls and opportunities for improvement in the management of allergy emergencies.MethodsA PubMed search from 1990 to 2015 was performed to identify all cases and reports pertaining to the use and misuse of epinephrine for anaphylaxis. Studies were assessed for obstacles or complications related to proper administration of epinephrine for treatment of allergic reactions, and were divided into problems originating with patients compared to healthcare providers.ResultsThere were 1840 publications related to epinephrine use, of which 61 reports met inclusion criteria for pitfalls in the use of epinephrine. The most common problems reported related to lack of autoinjector availability (22), inadequate education of patients or providers (9), uncertainty about when or how to administer epinephrine (9), concern for systemic effects (13), failure to administer (8), and accidental administration (2). Responsibility for errors was divided among patients (18), providers (39), or both (4).ConclusionEpinephrine is a potent medication with lifesaving indications and is the standard of care for treatment of anaphylaxis. The delivery of epinephrine in both trained and untrained populations carries certain pitfalls and complications that can have serious consequences. Identification of the scope of the problem is an important step in improving education for both providers and patients who are tasked with use of epinephrine for allergy emergencies.
Hydrophobic‐functionalized ZIF‐8 nanoparticles incorporated PDMS membranes for high‐selective separation of propane/nitrogen
Authors: Yuan Jianwei , Li Qianqian , Shen Jie , Huang Kang , Liu Gongping , Zhao Jing , Duan Jingui , Jin Wanqin 
Published: November 2016

AbstractIt is still a great challenge to prepare high performance mixed matrix membranes (MMMs) because of the difficulty in finely tuning the compatibility between filler and organic phases. In this work, ZIF‐8 nanoparticles hydrophobically functionalized by 5, 6‐dimethylbenzimidazole (DMBIM) via shell ligand exchange (SLE) reaction were incorporated into polydimethylsiloxane (PDMS) matrix to fabricate defect‐free MMMs. Organic‐–inorganic interface compatibility was realized because of more abundant organic ligands from DMBIM. The effects of different loadings on membrane microstructure and gas separation performance were investigated systematically. A significantly enhanced C3H8/N2 separation performance with C3H8 permeability over 2.10 × 104 Barrer (91 % higher than that of pure PDMS membrane) and C3H8/N2 selectivity of 99.5 (116 % higher than that of pure PDMS membrane) were achieved. Additionally, the as‐prepared membrane also exhibited excellent stability during long term operation. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Towards transparent PMMA/SiO2 nanocomposites with promising scratch‐resistance by manipulation of SiO2 aggregation followed by in situ polymerization
Authors: Zhang Qing , Huang Wan‐Xia , Zhong Gan‐Ji 
Published: November 2016

ABSTRACTPoly(methyl methacrylate) grafted silica (SiO2‐g‐PMMA) was synthesized via in situ suspension polymerization. To achieve better uniform dispersion, hexadecyltrimethylammonium bromide (CTAB) was introduced into xylene to manipulate SiO2 aggregation. SiO2‐g‐PMMA or SiO2 was incorporated into PMMA matrix by in situ polymerization to prepare PMMA‐based nanocomposites. The effect of CTAB amount, in the range 0–35 wt %, on the modification was evaluated by DLS, TGA, and FTIR. Furthermore, morphology, optical, mechanical, and thermal properties of PMMA nanocomposites was characterized by SEM, UV–vis, DMA, and TGA. Owing to surface functionalization, SiO2‐g‐PMMA exhibited far more excellent compatibility and dispersion in matrix compared with SiO2. Surface hardness and thermal properties of nanocomposites were enhanced significantly under the premise in high transparency. It is expected that transparent nanocomposites with promising scratch‐resistance could have wide applications, such as airplane shielding window and daily furniture. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44612.
Effect of optimization methods on Hansen solubility ellipsoids
Authors: Weng Ming 
Published: November 2016

ABSTRACTIn Hansen solubility parameters (HSPs) space, the solubility region of a solute is modeled as an axis‐aligned ellipsoid, of which Hansen sphere is a special case. The solubility ellipsoids of six materials are determined by the data fit function proposed by Hansen and a new objective function, both solved by a hybrid global‐local search algorithm. From the calculated and reported results, the validity and applicability of four types of currently used optimization methods are analyzed, the findings of and reasons for disputable problems are elucidated. The results reveal that the objective function defined for finding a smallest ellipsoid enclosing all good solvents and having the lowest number of outliers leads to reliable results, thereby has advantages over the methods based on the data fit function. The global convergence and capability of locating multiple optima are essential for a search algorithm used for determining solubility regions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44621.
The morphology evolution and crystallization behavior of microinjection molded polyoxymethylene/molybdenum disulfide nanocomposite
Authors: Yang Sen , Chen Yinghong , Yang Chaonan , Ding Weiwei 
Published: November 2016

ABSTRACTMicroinjection molding was carried out on polyoxymethylene (POM)/molybdenum disulfide (MoS2) nanocomposite prepared by solid state shear milling (S3M) technology. The morphology evolution and crystallization behavior were then investigated under different conditions of mold temperature and injection speed. The comparison between the microinjection molded micropart with conventional injection molded macropart was also conducted. Results showed that the higher mold temperature could improve the filling property and replication quality. The MoS2 particles played a heterogeneous nucleation role and remarkably affected the crystallization process of POM. Meanwhile, the crystallization orientation and skin‐core structure induced by the shear stress presented the similar evolution tendency under different microinjection conditions. The multi‐melting behaviors of microparts occurring under different microinjection conditions were attributed to the formation of shish‐kebab structures. The increase of crystallinity and the reduction of mechanical property occurring in macropart are related to its crystallization morphology formed, which is different from that of micropart. The results of this work would lay a foundation for preparation of POM/MoS2 transmission microparts with good comprehensive performance. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44625.
Encapsulated graphenes through ultrasonically initiated in situ polymerization: A route to high dielectric permittivity, low loss materials with low percolation threshold
Authors: Fan Ping , Wang Lei , Jia Shunxin , Chen Feng , Yang Jintao , Zhong Mingqiang 
Published: November 2016

ABSTRACTTo improve dielectric performance of polystyrene (PS) without sacrificing its flexibility and processability, PS encapsulated graphene sheets (PSG) were synthesized by ultrasonically initiated in situ polymerization and was incorporated into PS matrix as fillers. The structure and properties of the obtained PSG were investigated by Fourier transform infrared, transmission electron microscopy, scanning electron microscope, and atom force microscopies. The results showed that the in situ formed PS layers attached on the surface of graphene and there were strong interfacial interactions between them. In virtue of this core‐shell architecture and intrinsic properties of PSG, PS/PSG nanocomposites exhibited improved dielectric performance and a typical percolation transition with very low percolation threshold of 0.2 wt %. Compared with pure PS, significantly increased dielectric permittivity and a low loss tangent were observed for the composites. These composites might be potential flexible dielectric materials for use in high‐frequency capacitors with low loss. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44628.
Compressive stress relaxation modeling of butadiene rubber under thermo‐oxidative aging
Authors: Zheng Wei , Zhao Xiuying , Li Qiangguo , Chan Tung W. , Zhang Liqun , Wu Sizhu 
Published: November 2016

ABSTRACTThe compressive stress relaxation tests of butadiene rubber (BR) at different thermo‐oxidative aging temperatures were carried out. Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR‐ATR) was used to observe the variations of internal groups before and after the thermo‐oxidative aging. Magnetic resonance‐crosslink density (MR‐XLD) spectroscopy was used to measure the crosslink densities. The results showed the compressive stress relaxation of BR during thermo‐oxidative aging was dominated by chemical reactions: crosslinking, chain scission, and oxidation. Then an empirical model and an amendatory standard linear solid (SLS) model were put forward to describe the compressive stress relaxation behavior of BR. Both models fitted the data well. The SLS model, based on the aging mechanism of BR, not only made up the disadvantages of the empirical model, but also considered the changes of intrinsic viscosity (η) during the thermo‐oxidative aging of BR. The SLS model showed that the thermo‐oxidative aging of BR was mainly dominated by the crosslinking and oxidation reactions. This research proposes the amendatory SLS model and has important significance for study the stress relaxation behavior of crosslinked rubbers during thermo‐oxidative aging. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44630.
Synthesis, characterization, and catalytic activity of fluorescent polyimide nanocomposites
Authors: Sribala Govindarajan , Meenarathi Balakrishnan , Anbarasan Ramasamy 
Published: November 2016

ABSTRACTA fluorescent polyimide (PI) was synthesized by using perylene tetracarboxylic dianhydride (PTCDAH) and a oxydianiline (ODA) in N‐methyl pyrrolidone (NMP) solvent at 160 °C for 5 h under nitrogen atmosphere. Similarly, the fluorescent PI nanocomposites were prepared in the presence of silver (Ag) and vanadium pentoxide (V2O5) nanoparticles under identical experimental conditions. The above synthesized PI and its nanocomposites were characterized by FTIR spectroscopy, UV‐visible spectroscopy, Fluorescence emission spectroscopy, DSC, TGA, SEM, and FESEM. The data are carefully analyzed and compared with the literature values. The catalytic activity of the fluorescent nanocomposite fiber was tested towards the reduction of p‐nitrophenol (NiP), Cr(VI) and Rhodamine6G (R6G) dye. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44633.
MFI Acid Catalysts with Different Crystal Sizes and Porosity for the Conversion of Furanic Compounds in Alcohol Media
Authors: Antunes Margarida M. , Lima Sérgio , Fernandes Auguste , Magalhães Ana L. , Neves Patrícia , Silva Carlos M. , Ribeiro Maria F. , Chadwick David , Hellgardt Klaus , Pillinger Martyn , Valente Anabela A. 
Published: November 2016

AbstractSolid acid catalysts possessing MFI topology and different crystal sizes and porosities were explored for the conversion of carbohydrate‐biomass‐derived α‐angelica lactone and 5‐(hydroxymethyl)furfural, in 1‐butanol at T=120–170 °C, to give levulinate esters and furanic ethers. Micro/mesoporous microcrystalline catalysts were prepared by post‐synthesis base/acid treatments of ZSM‐5 zeolite; the influence of the desilication (base) conditions on the material properties was investigated. A nanocrystalline ZSM‐5 sample was synthesised by using hydrothermal, dynamic conditions and used as a reference material. A comparison of the catalytic performances of materials featuring different morphological, textural, and acid properties highlights a complex interplay between the acid and textural properties. The best‐performing catalyst (MZS0.6) was obtained by post‐synthesis‐treatment; fairly good catalytic stability was confirmed by catalyst recycling, contact tests, and characterisation of the spent catalyst. MZS0.6 was compared with the macrorecticular ion‐exchange resin Amberlyst‐15, chosen as a benchmark solid acid catalyst, in the two reaction systems.
Catalytically Triggered Energy Release from Strained Organic Molecules: The Surface Chemistry of Quadricyclane and Norbornadiene on Pt(111)
Authors: Bauer Udo , Mohr Susanne , Döpper Tibor , Bachmann Philipp , Späth Florian , Düll Fabian , Schwarz Matthias , Brummel Olaf , Fromm Lukas , Pinkert Ute , Görling Andreas , Hirsch Andreas , Bachmann Julien , Steinrück Hans‐Peter , Libuda Jörg , Papp Christian 
Published: November 2016

AbstractWe have investigated the surface chemistry of the polycyclic valence‐isomer pair norbornadiene (NBD) and quadricyclane (QC) on Pt(111). The NBD/QC system is considered to be a prototype for energy storage in strained organic compounds. By using a multimethod approach, including UV photoelectron, high‐resolution X‐ray photoelectron, and IR reflection–absorption spectroscopic analysis and DFT calculations, we could unambiguously identify and differentiate between the two molecules in the multilayer phase, which implies that the energy‐loaded QC molecule is stable in this state. Upon adsorption in the (sub)monolayer regime, the different spectroscopies yielded identical spectra for NBD and QC at 125 and 160 K, when multilayer desorption takes place. This behavior is explained by a rapid cycloreversion of QC to NBD upon contact with the Pt surface. The NBD adsorbs in a η2:η1 geometry with an agostic Pt−H interaction of the bridgehead CH2 subunit and the surface. Strong spectral changes are observed between 190 and 220 K because the hydrogen atom that forms the agostic bond is broke. This reaction yields a norbornadienyl intermediate species that is stable up to approximately 380 K. At higher temperatures, the molecule dehydrogenates and decomposes into smaller carbonaceous fragments.
“Bis‐Click” Ligation of DNA: Template‐Controlled Assembly, Circularisation and Functionalisation with Bifunctional and Trifunctional Azides
Authors: Yang Haozhe , Seela Frank 
Published: November 2016

AbstractLigation and circularisation of oligonucleotides containing terminal triple bonds was performed with bifunctional or trifunctional azides. Both reactions are high yielding. Template‐assisted bis‐click ligation of two individual non‐complementary oligonucleotide strands was accomplished to yield heterodimers exclusively. In this context, the template fulfils two functions: it accelerates the ligation reaction and controls product assembly (heterodimer vs. homodimer formation). Intermolecular bis‐click circularisation of one oligonucleotide strand took place without template assistance. For construction of oligonucleotides with terminal triple bonds in the nucleobase side chain, 7‐ or 5‐functionalised 7‐deaza‐dA and dU residues were used. These oligonucleotides are directly accessible by solid‐phase synthesis. When trifunctional azides were employed instead of bifunctional linkers, functionalisation of the remaining azido group was performed with small molecules such as 1‐ethynyl pyrene, biotin propargyl amide or with ethynylated oligonucleotides. By this means, branched DNA was constructed.