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The iridium-catalyzed asymmetric hydrogenation of β-keto esters with chiral tridentate P,N,N-ligands (f-amphox) has been developed. Under the optimized conditions, a wide range of β-keto esters can...

The Ir-catalyzed asymmetric hydrogenation of simple aromatic ketones with chiral ferrocenyl P,N,N-ligands has been developed. Under the optimized conditions, a wide range of ketones were hydrogenated to afford the corresponding chiral alcohols in good to excellent enantioselectivities (up to 98% ee).

The Ir-catalyzed asymmetric hydrogenation of β-keto esters with chiral ferrocenyl P,N,N-ligands has been developed. Under the optimized conditions, a wide range of β-keto esters were hydrogenated to afford the corresponding β-hydroxy esters in good to excellent enantioselectivities (up to 95% ee).

Novel hierarchical multi-porous carbonaceous beads were prepared by a simple process derived from nano-CaCO3 in-situ encapsulated hydrogels for the efficient batch and column removal of antibiotics from water. The obtained material (CCx-CB) was characterized by several techniques and methodologies such as, SEM, TEM, XRD, Raman, BET, MIP and FTIR. To evaluate the feasibility of CCx-CB carbonaceous beads as a potential adsorbent for antibiotic removal, batch adsorption experiments and fixed bed column experiments were conducted using tetracycline as the model antibiotic. The results showed that CCx-CB carbonaceous beads were effective in removing tetracycline with no significant change at pH (3.0–7.0). The adsorption of TC onto CCx-CB carbonaceous beads better fitted the pseudo-second-order kinetics model, and the maximum adsorption capacity calculated from Langmuir isotherm model was 279.3 mg/g at pH 7.0. In the fixed bed column experiments, lower influent TC concentration and lower flow rate lead to favorable adsorption of TC on CCx-CB carbonaceous beads. The Adams-Bohart and Thomas models were applied to the experimental data to predict the breakthrough curves using non-linear regression. More significantly, the carbonaceous beads also exhibit excellent regeneration ability over the adsorption-desorption process. The obtained results suggested that the CCx-CB exhibit a promising candidate for tetracycline removal because of their highly effective TC adsorption capacity, low cost and good regenerability.

The asymmetric hydrogenation of N-arylimines with the chiral phosphine-phosphoramidite ligand, (Sc,Sa)-PEAPhos 2b, has been developed. The results revealed that the presence of the substituents on the 3,3′-positions of the binaphthyl backbone significantly improved the enantioselectivity. The utility of this methodology was demonstrated in the synthesis of the chiral fungicide (R)-metalaxyl.

The Large High Altitude Air Shower Observatory (LHAASO) will be constructed at Mt. Haizishan, Sichuan Province, China. Among several detector components of the LHAASO, the Water Cherenkov Detector Array (WCDA) is of great importance for gamma-ray astronomy from 100 GeV to 30 TeV. The single-channel counting rate of a photo- multiplier tube can reach as high as 30 -35 kHz, most of them are background noise hits from the low energy cosmic ray showers, bringing a big challenge on data transferring, data storage and event reconstruction. In this paper, a dedicated trigger scheme and a fast noise filtering method aiming to deal with these high rate background noise hits are introduced. These methods are tested with some Monte Carlo simulation data, showing a fair efficiency in filtering background noise hits, while most of the real shower signals are kept. This method is proposed to be applied in a stage of the online processing just after the data are acquired in LHAASO-WCDA.

Gold-titania/protonated zeolite (Au–TiO 2 /HZSM-5) composite photocatalysts were prepared via the sol–gel and impregnation processing. The structural features of the photocatalysts were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and ultraviolet visible diffuse reflection spectroscopy (UV–vis); the adsorption and photo-degradation of Methyl Orange (MO) were studied in the aqueous solution. The results showed that the nanoAu particles were incorporated in TiO 2 /HZSM-5. The introduction of Au particles not only maintained the adsorption capacity of photocatalysts, but also promoted the photodegradation efficiency of Methyl Orange (MO). The effects of Au content, TiO 2 content, catalyst amount and calcination temperature were examined and the repeatability of photocatalytic activity was also tested. Moreover, the Methyl Orange (MO) photodegradation activity of 0.32%Au-25%TiO 2 /HZSM-5 nanocomposites is the best. A plausible mechanism is proposed for the route of degradation.

Ningwu porphyrite-type iron deposits are located in Ningwu Mesozoic volcanic basin, which belongs to the middle and lower reaches of the Yangtze River metallogenic province. The volcanic rocks can be divided into Longwangshan, Dawangshan, Gushan and Niangniangshan Formations from early to late. All these volcanic rocks are rich in alkali, and show the similar patterns in rare earth element (REE) distribution. However, some differences can be found in the trace elements and REE patterns. The study of petrology and REE geochemical characteristics shows that these rocks are derived from the underplating of the lithospheric mantle and are contaminated by crustal materials, undergo AFC process during the magmatic evolution.

Western Tianshan High-pressure (HP)-metamorphic belt is characterized by developed High-pressure (HP) veins, which are composed by HP-metamorphic minerals. The host rocks of the HP-veins are mainly composed by eclogites and blueschists. As the direct record of the deep fluids in the paleo-subduction zones, the HP-veins can provide us deep samples for probing into the deep fluids in the subduction zones. Fluids in the deep subduction zones play an important role in crust-mantle exchange related to plate subduction process. The electron microprobe analyses of HP-metamorphic minerals omphacite inside the veins and host rocks in western Tianshan high-pressure metamorphic belt is mostly paid attention. The result shows that the composition of the omphacite from HP-veins have the same composition of the omphacite from the host rocks, which indicates that the fluids from which the HP-vein precipitated originated from the host rock.

Dabashan Thrust and Fold Belt is situated in the transfer zone between Qinling Orogen and Sichuan Basin, where multi-generation calcite veins were developed. Two kinds of veins, bedding-parallel and fracture-filled veins, were collected for analyses of rare-earth elements (REE), samarium-neodymium and strontium isotopes. The total REE contents of the calcites from the bedding-parallel vein are much higher than those from fracture-filled veins and are rich in light REE (LREE). The chondrite-normalized patterns of REE curves of the calcites from fracture-filled veins are flatten. The 87Sr/86Sr and 143Nd/144Nd ratios of calcites from bedding-parallel vein are from 0.71068 to 0.71115 and from 0.51192 to 0.512058, respectively. On the 147Sm/143Nd vs 143Nd/144Nd diagram, the six samples from the bedding-parallel vein give a Sm-Nd isochron age of 357±230 Ma (2σ)( MSWD = 24) with an initial 143Nd/144Nd ratio of 0.51168±0.00019. However, the plots of the four samples from fracture-filled veins are rather scatter either on 147Sm/143Nd vs 143Nd/144Nd or on 87Sr/86Sr vs 143Nd/144Nd diagram. The fluids, from which the two kinds of veins precipitated, are different in origin and flowing.

The highly enantioselective asymmetric hydrogenation of N-arylamines using chiral phosphine-phosphoramidite ligands is demonstrated.

The key point of speaker recognition is to extract the unique, effective, stable and reliable features that can stand for the personality of the speaker from the speech signal. This paper applied the psychologically weighted technology in mel-cepstrum analysis and adopted the Signal-to-Mask Ratios (SMRS) obtained from the psychoacoustic model as the weighting function to obtain the weighted mel-cepstrum coefficients (WMCEP) as features in speaker recognition. Experiments showed that the WMCEP not only described the speaker’s formant much better than MFCC and MCEP, but also had robustness to some extent for speaker recognition.