bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immersion mode ice nucleation measurements with the new Portable Immersion Mode Cooling chAmber (PIMCA)
Authors: Kohn Monika , Lohmann Ulrike , Welti André , Kanji Zamin A. 
Published: April 2016

AbstractThe new Portable Immersion Mode Cooling chAmber (PIMCA) has been developed for online immersion freezing of single‐immersed aerosol particles. PIMCA is a vertical extension of the established Portable Ice Nucleation Chamber (PINC). PIMCA immerses aerosol particles into cloud droplets before they enter PINC. Immersion freezing experiments on cloud droplets with a radius of 5–7 μm at a prescribed supercooled temperature (T) and water saturation can be conducted, while other ice nucleation mechanisms (deposition, condensation, and contact mode) are excluded. Validation experiments on reference aerosol (kaolinite, ammonium sulfate, and ammonium nitrate) showed good agreement with theory and literature. The PIMCA‐PINC setup was tested in the field during the Zurich AMBient Immersion freezing Study (ZAMBIS) in spring 2014 in Zurich, Switzerland. Significant concentrations of submicron ambient aerosol triggering immersion freezing at T > 236 K were rare. The mean frozen cloud droplet number concentration was estimated to be 7.22·105 L−1 for T < 238 K and determined from the measured frozen fraction and cloud condensation nuclei (CCN) concentrations predicted for the site at a typical supersaturation of SS = 0.3%. This value should be considered as an upper limit of cloud droplet freezing via immersion and homogeneous freezing processes. The predicted ice nucleating particle (INP) concentration based on measured total aerosol larger than 0.5 μm and the parameterization by DeMott et al. (2010) at T = 238 K is INPD10=54 ± 39 L−1. This is a lower limit as supermicron particles were not sampled with PIMCA‐PINC during ZAMBIS.
The Use of27Al NMRto Study Aluminum Compounds: A Survey of the Last 25 Years
Authors: Martineau Charlotte , Taulelle Francis , Haouas Mohamed 
Published: April 2016

AbstractUse of27Al nuclear magnetic resonance (NMR) spectroscopy for the study of the chemistry of aluminum in a variety of compounds during the last 25 years is reported. A compilation of NMR data, including chemical shifts and heteronuclear scalar couplings, is provided for a wide range of families of aluminum compounds in both solution and solid state. Recent methodological and technological advances in the field of quadrupolar NMR are detailed and their applications to27Al nucleus are illustrated. The potential of this technique is exemplified with some representative studies of relevance to mineral, biological, and organic aluminum‐based systems.
Advances in the Catalysis of Organic Processes by Metal Phenolates
Authors: Da Silva Serra Maria Elisa , Murtinho Dina M. B. 
Published: April 2016

Abstract
Transition‐metal catalysts with phenolate ligands comprise a great variety of compounds with appropriate characteristics capable of promoting numerous reactions of extreme importance in synthetic organic chemistry. Included in these transformations are oxidations of alkenes, sulfides, alcohols, and alkanes, cyanations, alkynylations, alkylations, hydroaminations, and nitroaldol reactions. An extensive review of the catalysis of organic processes by metal phenolates has been presented in a previous volume of this series. This chapter is an update of the advances published from 2011 to the beginning of 2015, with emphasis on the type of reactions catalyzed by metal phenolates that have gained more attention in the literature during this period.
Advances in Deposition of Metals from Metal Enolates
Authors: Lang Heinrich , Adner David , Georgi Colin 
Published: April 2016

AbstractThis chapter describes the use of metal enolates as precursors for the deposition and growth of nano‐sized materials of a large variety of metal, mixed metal‐metal oxide, and alloy layers and patterns, an area that has rapidly developed during the last couple of decades. As metal enolates, mostly mononuclear main group, transition metal, and rare earth metal complexes featuring various β‐diketonate or β‐ketoiminate ligands have been used. Based on their intrinsic properties, for example, reactivity, transparency, conductivity, and magnetism, a large variety of metal and/or metal oxide deposits are available at present. As deposition processes, mainly gas‐phase (e.g., CVD2–9 and ALD8–19) or liquid‐phase procedures (including spin‐coating, dip‐coating, sol–gel, and printing techniques) were used. Controlled decomposition of the appropriate metal enolates allows the generation of diverse metal and metal oxide materials, for example, dense or porous thin layers and nanomaterials in the form of particles, dots, rods, tubes, and wires. Where appropriate, the similarities and differences, including elementary decomposition steps that are common for the respective metal enolate precursors, are discussed as well.
Working Memory Capacity and Self‐Explanation Strategy Use Provide Additive Problem‐Solving Benefits
Authors: Redifer Jenni L. , Therriault David J. , Lee Christine S. , Schroeder Amber N. 
Published: April 2016

SummaryThe present study examined the impact of working memory capacity (WMC) on college students' ability to solve probability problems while using a self‐explanation strategy. Participants learned to solve probability problems in one of three conditions: a backward‐faded self‐explanation condition, an example problem pairs self‐explanation condition, or a control (no self‐explanation) condition. Even when accounting for the impact of WMC, learning to problem‐solve using self‐explanation led to superior problem‐solving performance. Conditions that prompted self‐explanation during problem‐solving resulted in significantly better problem‐solving performance than the control condition. These findings provide insight into the influence of individual differences on problem‐solving when strategies are provided, as well as information about the effectiveness of the self‐explanation strategy during mathematical problem‐solving. Copyright © 2016 John Wiley & Sons, Ltd.
Restricted Equilibrium Swelling of n‐Alkanes Posed by Ginger Spent Filled Polyurethane Green Composites during Sorption, Desorption, Resorption, and Redesorption Processes
Authors: Mahadevaiah Chethana ,   Siddaramaiah 
Published: April 2016

ABSTRACTPolyurethane (PU) based green composites with varying amounts of ginger spent (GS) have been fabricated and characterized for swelling and molecular transport behaviors in n‐alkane probe molecules. Sorption–desorption–resorption–redesorption (S‐D‐RS‐RD) behaviors have been performed to determine the true factor for transport coefficient. Sorption results are obtained by a gravimetric method and diffusion coefficient (D) has been calculated using Fick's equation for the linear data points of time‐dependent sorption/resorption curves. The observation was made that diffusion coefficient follows Fick's rule. Sorption studies have been carried out at 25, 40, and 60°C. A significant increase in sorption values has been noticed with raise in temperature. Sorption (S) and diffusion (D) coefficients of n‐alkanes depend on GS content in PU matrix. From the temperature dependence of diffusion and permeation (P) coefficients, the Arrhenius activation parameters have been used to estimate activation parameters such as diffusion (ED) and permeation (EP). Thermodynamic parameters such as enthalpy (ΔH) and entropy (ΔS) have been interpreted for sorption/resorption results. The percentage weight change for desoption and redesorption processes has been recorded; these results depend on the volatility of the penetrant molecules.
Quality Choice and Market Access: Evidence from Chilean Wine Grape Production
Authors: Jano Pilar A. 
Published: April 2016

ABSTRACTThis paper examines the determinants of becoming a producer of high‐quality wine grapes. We explore the case of wine‐grape farmers in Chile where we observe a bifurcation of farmer types.“Quasi‐subsistence” farmers produce traditional wine‐grape varieties and complement their subsistence income with cash coming from wine‐grape sale. On the other hand, we observe “entrepreneurial” farmers who produce classic varieties that have the potential to produce high‐quality wines. We study this bifurcation empirically using primary data collected during the 2011–2012 growing season. We find that wealth and cultivation ability provide economically and statistically significant explanatory power, but that buyer characteristics also matter. Our results suggest that a farmer's entry into the supply chain for high‐quality production is not an individual's choice. Rather it is a joint decision that cannot be fully understood without considering the objectives, incentives, and information of supplier and buyer. [EconLit citations: O14; Q140; L26].
Solvent‐Free Pot‐, Atom‐ and Step‐Economic Synthesis of Novel Benzo[d]thiazole‐[1,3]‐thiazine Hybrids in a One‐Pot Reaction
Authors: Wadhwa Preeti , Kaur Tanpreet , Sharma Anuj 
Published: April 2016

AbstractThe first catalyst‐ and solvent‐free synthesis of novel benzo[d]thiazole‐[1,3]‐thiazine hybrids from benzo[d]thiazol‐2‐amines, isothiocyanates and dialkyl acetylenedicarboxylates with no more than 30 min of microwave irradiation is described. Moreover, the proposed strategy involves neither tedious workup nor column purification steps. This approach provides a diversity‐oriented route for the rapid assembly of benzo[d]thiazole‐[1,3]‐thiazine frameworks. Furthermore, the methodology has excellent green credentials, scoring well in a number of green metrics, hence showing this approach to be an ideal green and sustainable process.
Nonlinear optical characteristics of monolayer MoSe2
Authors: Le Chinh Tam , Clark Daniel J. , Ullah Farman , Senthilkumar Velusamy , Jang Joon I. , Sim Yumin , Seong Maeng‐Je , Chung Koo‐Hyun , Park Hyoyeol , Kim Yong Soo 
Published: April 2016

In this study, we utilized picosecond pulses from an Nd:YAG laser to investigate the nonlinear optical characteristics of monolayer MoSe2. Two‐step growth involving the selenization of pulsed‐laser‐deposited MoO3 film was employed to yield the MoSe2 monolayer on a SiO2/Si substrate. Raman scattering, photoluminescence (PL) spectroscopy, and atomic force microscopy verified the high optical quality of the monolayer. The second‐order susceptibility χ(2) was calculated to be ∼50 pm V−1 at the second harmonic wavelength ∼810 nm, which is near the optical gap of the monolayer. Interestingly, our wavelength‐dependent second harmonic scan can identify the bound excitonic states including negatively charged excitons much more efficiently, compared with the PL method at room temperature. Additionally, the MoSe2 monolayer exhibits a strong laser‐induced damage threshold ∼16 GW cm−2 under picosecond‐pulse excitation. Our findings suggest that monolayer MoSe2 can be considered as a promising candidate for high‐power, thin‐film‐based nonlinear optical devices and applications.
Functionalization of Two‐Dimensional MoS2: On the Reaction Between MoS2 and Organic Thiols
Authors: Chen Xin , Berner Nina C. , Backes Claudia , Duesberg Georg S. , McDonald Aidan R. 
Published: April 2016

AbstractTwo‐dimensional layered transition metal dichalcogenides (TMDs) have attracted great interest owing to their unique properties and a wide array of potential applications. However, due to their inert nature, pristine TMDs are very challenging to functionalize. We demonstrate a general route to functionalize exfoliated 2H‐MoS2 with cysteine. Critically, MoS2 was found to be facilitating the oxidation of the thiol cysteine to the disulfide cystine during functionalization. The resulting cystine was physisorbed on MoS2 rather than coordinated as a thiol (cysteine) filling S‐vacancies in the 2H‐MoS2 surface, as originally conceived. These observations were found to be true for other organic thiols and indeed other TMDs. Our findings suggest that functionalization of two‐dimensional MoS2 using organic thiols may not yield covalently or datively tethered functionalities, rather, in this instance, they yield physisorbed disulfides that are easily removed.
Insights Into the Allosteric Inhibition of the SUMO E2 Enzyme Ubc9
Authors: Hewitt William M. , Lountos George T. , Zlotkowski Katherine , Dahlhauser Samuel D. , Saunders Lindsey B. , Needle Danielle , Tropea Joseph E. , Zhan Chendi , Wei Guanghong , Ma Buyong , Nussinov Ruth , Waugh David S. , Schneekloth John S. 
Published: April 2016

AbstractConjugation of the small ubiquitin‐like modifier (SUMO) to protein substrates is an important disease‐associated posttranslational modification, although few inhibitors of this process are known. Herein, we report the discovery of an allosteric small‐molecule binding site on Ubc9, the sole SUMO E2 enzyme. An X‐ray crystallographic screen was used to identify two distinct small‐molecule fragments that bind to Ubc9 at a site distal to its catalytic cysteine. These fragments and related compounds inhibit SUMO conjugation in biochemical assays with potencies of 1.9–5.8 mm. Mechanistic and biophysical analyses, coupled with molecular dynamics simulations, point toward ligand‐induced rigidification of Ubc9 as a mechanism of inhibition.
Unraveling Epitaxial Habits in the NaLnF4 System for Color Multiplexing at the Single‐Particle Level
Authors: Zhang Yuhai , Huang Ling , Liu Xiaogang 
Published: April 2016

AbstractWe report an epitaxial growth technique for scalable production of hybrid sodium rare‐earth fluoride (NaLnF4) microcrystals, including NaYF4, NaYbF4, and NaLuF4 material systems. The single crystalline nature of the as‐synthesized products makes them strong upconversion emission. The freedom of combining a lanthanide activator (Er3+ or Tm3+) with a sensitizer (Yb3+) at various doping concentrations readily gives access to color multiplexing at the single‐particle level. Our kinetic and thermodynamic investigations on the epitaxial growth of core–shell microcrystals using NaLnF4 particle seeds suggest that within a certain size regime it is plausible to exert precise control over shell thickness and growth orientation under hydrothermal conditions.
Mono‐ und ditope Bisfunktionalisierung von Graphen
Authors: Knirsch Kathrin C. , Schäfer Ricarda A. , Hauke Frank , Hirsch Andreas 
Published: April 2016

AbstractWir berichten zum ersten Mal über die Bisfunktionalisierung von Graphen auf der Basis zweier konsekutiver Reduktions‐ und kovalenter Additionsschritte. Dieser Ansatz wurde sowohl für die lösungsmittelbasierte Funktionalisierung von Graphen im präparativen Maßstab als auch für die Derivatisierung individueller Kohlenstofflagen auf Oberflächen genutzt. Im ersten Fall ist der elektrophile Angriff aus beiden Halbräumen der Basalebene möglich, was zum Aufbau spannungsfreier Architekturen führt. Im zweiten Fall hingegen gewinnen Retrofunktionalisierungsreaktionen an Bedeutung, insbesondere wenn das entsprechende Anion des Erstaddenden eine gute Abgangsgruppe darstellt.
Nonpeptidic Selective Inhibitors of the Chymotrypsin‐Like (β5 i) Subunit of the Immunoproteasome
Authors: Sosič Izidor , Gobec Martina , Brus Boris , Knez Damijan , Živec Matej , Konc Janez , Lešnik Samo , Ogrizek Mitja , Obreza Aleš , Žigon Dušan , Janežič Dušanka , Mlinarič‐Raščan Irena , Gobec Stanislav 
Published: April 2016

AbstractElevated expression of the immunoproteasome has been associated with autoimmune diseases, inflammatory diseases, and various types of cancer. Selective inhibitors of the immunoproteasome are not only scarce, but also almost entirely restricted to peptide‐based compounds. Herein, we describe nonpeptidic reversible inhibitors that selectively block the chymotrypsin‐like (β5i) subunit of the human immunoproteasome in the low micromolar range. The most potent of the reversibly acting compounds were then converted into covalent, irreversible, nonpeptidic inhibitors that retained selectivity for the β5i subunit. In addition, these inhibitors discriminate between the immunoproteasome and the constitutive proteasome in cell‐based assays. Along with their lack of cytotoxicity, these data point to these nonpeptidic compounds being suitable for further investigation as β5i‐selective probes for possible application in noncancer diseases related to the immunoproteasome.
Astellifadiene: Structure Determination by NMR Spectroscopy and Crystalline Sponge Method, and Elucidation of its Biosynthesis
Authors: Matsuda Yudai , Mitsuhashi Takaaki , Lee Shoukou , Hoshino Manabu , Mori Takahiro , Okada Masahiro , Zhang Huiping , Hayashi Fumiaki , Fujita Makoto , Abe Ikuro 
Published: April 2016

AbstractGenome mining of a terpene synthase gene from Emericella variecolor NBRC 32302 and its functional expression in Aspergillus oryzae led to the production of the new sesterterpene hydrocarbon, astellifadiene (1), having a 6‐8‐6‐5‐fused ring system. The structure of 1 was initially investigated by extensive NMR analyses, and was further confirmed by the crystalline sponge method, which established the absolute structure of 1 and demonstrated the usefulness of the method in the structure determination of complex hydrocarbon natural products. Furthermore, the biosynthesis of 1 was proposed on the basis of isotope‐incorporation experiments performed both in vivo and in vitro. The cyclization of GFPP involves a protonation‐initiated second cyclization sequence, 1,2‐alkyl migration, and 1,5‐hydride shift to generate the novel scaffold of 1.
Triply Linked Corrole Dimers
Authors: Ooi Shota , Tanaka Takayuki , Park Kyu Hyung , Kim Dongho , Osuka Atsuhiro 
Published: April 2016

AbstractThe oxidation of 10–10′ singly linked corrole dimers with DDQ at low concentration in CHCl3 afforded meso–meso, β–β, β–β triply linked 2H‐corrole dimers (with two inner NH groups in each corrole unit), which exhibited characteristic 1H NMR and absorption spectra attributable to their nonaromatic electronic networks. These 2H‐corrole dimers were reduced with NaBH4 to aromatic 3H‐corrole dimers, which were unstable and easily oxidized back to the 2H‐corrole dimers upon exposure to air. Bis(zinc(II)) complexes of the 2H‐corrole dimers were synthesized and characterized as rare examples of nonaromatic zinc(II) corrole complexes.
Mono‐ and Ditopic Bisfunctionalization of Graphene
Authors: Knirsch Kathrin C. , Schäfer Ricarda A. , Hauke Frank , Hirsch Andreas 
Published: April 2016

AbstractFor the first time, the bisfunctionalization of graphene by employing two successive reduction and covalent bond forming steps is reported. Bulk functionalization in dispersion and functionalization of individual sheets deposited on surfaces have both been carried out. Whereas in the former case attacks from both sides of the basal plane are possible and can lead to strain‐free architectures, in the latter case, retrofunctionalizations can become important when the corresponding anion of the addend is a sufficiently good leaving group.
π‐Extended “Earring” Porphyrins with Multiple Cavities and Near‐Infrared Absorption
Authors: Rao Yutao , Kim Taeyeon , Park Kyu Hyung , Peng Fulei , Liu Lei , Liu Yunmei , Wen Bin , Liu Shubin , Kirk Steven Robert , Wu Licheng , Chen Bo , Ma Ming , Zhou Mingbo , Yin Bangshao , Zhang Yuexing , Kim Dongho , Song Jianxin 
Published: April 2016

Abstractβ,β‐tripyrrin‐bridged earring porphyrins were synthesized through Suzuki–Miyaura cross coupling reactions. These porphyrinoids have multiple cavities and can accommodate two or three metal ions per molecule. The structures of the porphyrins have been elucidated by x‐ray diffraction analysis, and feature curved π planes. The electronic spectra of the porphyrins exhibit near‐infrared (NIR) absorptions and metal insertion leads to red‐shifted and intensified absorption features. Electrochemical analysis and transient absorption measurements indicated that the porphyrins exhibit effective electronic communication between their central and peripheral moieties.
Effect of unfunctionalized and HNO3‐functionalized MWCNT on the mechanical and electrical performances of PEMFC bipolar plates
Authors: Athmouni Nafaa , Mighri Frej , Elkoun Saïd 
Published: April 2016

ABSTRACTThis study aims at developing lightweight and high performance electrically conductive nanocomposites for proton exchange membrane fuel cell (PEMFC) bipolar plates (BPPs). These composites were made from an optimized co‐continuous mixture of Polyethylene terephthalate (PET) and polyvinylidene fluoride (PVDF) reinforced with highly conductive carbon additives composed of carbon black (CB) and synthetic graphite (GR). Multiwall carbon nanotubes (MWCNT) were functionalized then used to improve BPPs electrical conductivity and their mechanical properties, such as flexural and impact strengths. It was observed that the best BPP prototype was obtained using nitric acid (HNO3)‐functionalized MWCNT. The latter led to the smothest BPP surface, the lowest through‐plane resitivity (0.12 Ω cm) and the highest impact and flexural strengths. These results are attributed to the improved dispersion of the functionalized MWCNT, a result of their best compatibilization with the (PET/PVDF) polymeric phase. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43624.
Synthesis and properties of new water‐soluble copolymers based on methyl acrylic acid sucrose ester and methyl acrylic acid
Authors: Chen Yan , Liu Jin , Li Zhen 
Published: April 2016

ABSTRACTThe new series of copolymers were obtained based on free radical solution copolymerization by mixing self‐made methyl acrylic acid sucrose ester (MASE) and methyl acrylic acid (MAA) with different ratios. Copolymerization behavior and properties of the new copolymers was investigated with the reaction time, temperature, monomer ratios and characterized by Fourier transform infrared spectra (FT‐IR), carbon nuclear magnetic resonance (13C NMR), and intrinsic viscosity. The results indicated that sucrose was successfully grafted onto poly (methyl acrylic acid). Further, it was demonstrated that low temperature benefited the esterification of MASE. Importantly, the copolymers were founded to have good compatibility with polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), and polyethylene (PE). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2016,133, 43627.