There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

On August 17, 2017 at 12∶41:04 UTC the Advanced LIGO and Advanced Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with a combined signal-to-noise ratio of 32.4 and a false-alarm-rate estimate of less than one per 8.0×10^{4}  years. We infer the component masses of the binary to be between 0.86 and 2.26  M_{⊙}, in agreement with masses of known neutron stars. Restricting the component spins to the range inferred in binary neutron stars, we find the component masses to be in the range 1.17-1.60  M_{⊙}, with the total mass of the system 2.74_{-0.01}^{+0.04}M_{⊙}. The source was localized within a sky region of 28  deg^{2} (90% probability) and had a luminosity distance of 40_{-14}^{+8}  Mpc, the closest and most precisely localized gravitational-wave signal yet. The association with the γ-ray burst GRB 170817A, detected by Fermi-GBM 1.7 s after the coalescence, corroborates the hypothesis of a neutron star merger and provides the first direct evidence of a link between these mergers and short γ-ray bursts. Subsequent identification of transient counterparts across the electromagnetic spectrum in the same location further supports the interpretation of this event as a neutron star merger. This unprecedented joint gravitational and electromagnetic observation provides insight into astrophysics, dense matter, gravitation, and cosmology.

/pdf/gw170817-observation-of-gravitational-waves-from-a-binary-q2x9byg981.pdf

GW170817: observation of gravitational waves from a binary neutron star inspiral

Metal halides perovskites, such as hybrid organic–inorganic CH3NH3PbI3, are newcomer optoelectronic materials that have attracted enormous attention as solution-deposited absorbing layers in solar cells with power conversion efficiencies reaching 20%. Herein we demonstrate a new avenue for halide perovskites by designing highly luminescent perovskite-based colloidal quantum dot materials. We have synthesized monodisperse colloidal nanocubes (4–15 nm edge lengths) of fully inorganic cesium lead halide perovskites (CsPbX3, X = Cl, Br, and I or mixed halide systems Cl/Br and Br/I) using inexpensive commercial precursors. Through compositional modulations and quantum size-effects, the bandgap energies and emission spectra are readily tunable over the entire visible spectral region of 410–700 nm. The photoluminescence of CsPbX3 nanocrystals is characterized by narrow emission line-widths of 12–42 nm, wide color gamut covering up to 140% of the NTSC color standard, high quantum yields of up to 90%, and radiativ...

/pdf/nanocrystals-of-cesium-lead-halide-perovskites-cspbx3-x-cl-4ktrqyr1d2.pdf

Nanocrystals of Cesium Lead Halide Perovskites (CsPbX3, X = Cl, Br, and I): Novel Optoelectronic Materials Showing Bright Emission with Wide Color Gamut

We report a detailed study on the first colloidal synthesis of NiAs nanocrystals. By optimizing the synthesis parameters, we were able to obtain trioctylphosphine-capped NiAs nanoplatelets with an average diameter of ∼10 nm and a thickness of ca. 4 nm. We then studied the performance of such NiAs nanocrystals as electrocatalysts for electrochemical water splitting reactions, namely, acidic hydrogen evolution reaction (HER) and alkaline oxygen evolution reaction (OER). These nanocrystals were found to be the most HER active ones among the transition metal arsenides reported to date despite exhibiting less than 40 h of stability under benchmark operative conditions (i.e., −10 mA cmgeo–2). When tested as alkaline OER electrocatalysts, our NiAs nanocrystals behaved as a pre-catalyst and transformed superficially into an active Ni-oxy/hydroxide. As a result, NiAs nanocrystals featured an OER activity higher than that of benchmark Ni0 nanocrystals. Noticeably, the OER performance, in terms of , was retained for up to 60 h of continuous operation. The present study highlights how transition metal arsenides, whose structural features could be successfully controlled through a proper tuning of the synthetic parameters, might represent an emerging class of materials for electrocatalytic applications.

Colloidal Synthesis of Nickel Arsenide Nanocrystals for Electrochemical Water Splitting

The realization of a stable lithium-metal free (LiMF) sulfur battery based on amorphous carbon anode and lithium sulfide (Li2S) cathode is here reported. In particular, a biomass waste originating full-cell combining a carbonized brewer's spent grain (CBSG) biochar anode with a Li2S-graphene composite cathode (Li2S70Gr30) is proposed. This design is particularly attractive for applying a cost-effective, high performance, environment friendly, and safe anode material, as an alternative to standard graphite and metallic lithium in emerging battery technologies. The anodic and cathodic materials are characterized in terms of structure, morphology and composition through X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron and Raman spectroscopies. Furthermore, an electrochemical characterization comprising galvanostatic cycling, rate capability and cyclic voltammetry tests were carried out both in half-cell and full-cell configurations. The systematic investigation reveals that unlike graphite, the biochar electrode displays good compatibility with the electrolyte typically employed in sulfur batteries. The CBSG/Li2S70Gr30 full-cell demonstrates an initial charge and discharge capacities of 726 and 537 mAh g−1, respectively, at 0.05C with a coulombic efficiency of 74%. Moreover, it discloses a reversible capacity of 330 mAh g−1 (0.1C) after over 300 cycles. Based on these achievements, the CBSG/Li2S70Gr30 battery system can be considered as a promising energy storage solution for electric vehicles (EVs), especially when taking into account its easy scalability to an industrial level. 

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/eem2.12567

Lithium‐metal free sulphur battery based on waste biomass anode and nano‐sized
 
 Li
 2
 S
 
 cathode

The anti-inflammatory activity of a new class of phenyl-pyrazolone derivatives, structurally related to phenidone, has been evaluated using the Croton oil ear test in mice as model of acute inflammation. Derivative 5h reduces the percentage of oedema similarly to indomethacin and more efficiently than phenylbutazone. The anti-inflammatory activity of these two reference drugs depends on their COX inhibition, but for the synthesized derivatives it has not been demonstrated a significant COX or LOX inhibition, as previously reported. While the anti-inflammatory activity of phenidone is correlated to its anti-oxidant properties, the redox potential of these compounds appears not decisive in the inflammatory process inhibition. In order to investigate the mechanism of action for these compounds, we quantified their anti-oxidant activity and the lipophilicity, and a relationship between the calculated logP and the percentage of oedema reduction was found. We hypothesize that the anti-inflammatory activity, recorded in vivo, could be related to lipophilic parameter of these compounds.

Anti-Inflammatory and Anti-Oxidant Activity of a New Class of Phenyl- Pyrazolone Derivatives

Oxidation of Diazo Compounds by Dimethyl Dioxirane: An Extremely Mild and Efficient Method for the Preparation of Labile α-Oxo Aldehydes.

The figure on the cover portrays a novel donor–acceptor nanoassembly, based on a single-walled carbon nanotube (SWNT) as the electron acceptor and poly(methyl methacrylate) (PMMA)-carrying porphyrin units (H2P) as the excited-state electron donors. In these supramolecular “polymer wraps”, reported on p. 871 by Guldi and co-workers, SWNTs quench the photoexcited H2P chromophores, resulting in the creation of microsecond-lived radical ion pairs.

Cover Picture: Novel Photoactive Single‐Walled Carbon Nanotube–Porphyrin Polymer Wraps: Efficient and Long‐Lived Intracomplex Charge Separation (Adv. Mater. 7/2005)

Mirko Prato

Papers

Colloidal Synthesis of Nickel Arsenide Nanocrystals for Electrochemical Water Splitting

Lithium‐metal free sulphur battery based on waste biomass anode and nano‐sized Li 2 S cathode

Anti-Inflammatory and Anti-Oxidant Activity of a New Class of Phenyl- Pyrazolone Derivatives

Oxidation of Diazo Compounds by Dimethyl Dioxirane: An Extremely Mild and Efficient Method for the Preparation of Labile α-Oxo Aldehydes.

Cover Picture: Novel Photoactive Single‐Walled Carbon Nanotube–Porphyrin Polymer Wraps: Efficient and Long‐Lived Intracomplex Charge Separation (Adv. Mater. 7/2005)