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The effect of incorporation manner of Zr on the textural properties, surface physicochemical properties, reduction degree and catalytic performance of Co/SBA-15 catalyst for the Fischer – Tropsch synthesis (FTS) was investigated. The catalysts were prepared by sequential impregnation, co-impregnation and in-situ synthesis method, respectively. The loading amount of Co and Zr remained constant in all catalysts with 15 wt.% and 5 wt.%, respectively. The catalysts were characterized by N 2 adsorption – desorption, X - ray diffraction (XRD), X - ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), temperature - programmed reduction (H 2 - TPR) and evaluated for the FTS. It was revealed that the Co 3 O 4 was considered as the main surface cobalt phase, and the BET surface area and pore size were decreased regardless of the incorporation manner. The reduction degree of cobalt species increased from 80% (Co/SBA-15) to 90% (Co/Zr/SBA-15) and 85% (CoZr/SBA-15) with the addition of Zr, except for the Co/Zr-SBA-15 catalyst (74%). The catalyst prepared by sequential impregnation method (Co/Zr/SBA-15) showed the highest selectivity of long-chain hydrocarbons (C 12 –C 22 , 53%) with the chain growth probability α up to 0.84, which could be attributed to the highest reducibility of cobalt species. [ABSTRACT FROM AUTHOR]

A glucose-containing imidazolium salt β-1-imidazole-2,3,4,6-tetraacetyl-D-glucopyranosyl bromide was firstly used as efficient noncovalent organocatalyst to promote the solvent-free preparation of ortho -aminocarbonitriles via a four-component condensation of aromatic aldehyde, cyclohexanone, and 2 equiv of malononitrile at room temperature. Seven bonds were cleaved while four new bonds were formed and a six-membered ring was constructed in one-pot. [ABSTRACT FROM AUTHOR]

A series of ZSM-5/SBA-15 composite supported Co catalysts were prepared and evaluated for the Fischer–Tropsch synthesis (FTS) aimed to maximise the selectivity of C 5 –C 22 hydrocarbons in the product. The composite support was prepared by physically mixing ZSM-5 and SBA-15 of varying proportions and the finished catalysts had a constant Co loading of 15wt.%. The catalysts were tested for their performance in a high pressure fixed-bed reactor operating at T = 240 °C, P = 2.0 MPa, H 2 /CO = 2 and GHSV = 1000 h − 1 . The composite supported catalysts were shown to have much improved catalytic performance over the respective single material supported catalysts. The catalyst with 20wt.% ZSM-5 in the composite support gave the maximum CO conversion (90.6%), maximum selectivity of C 5 –C 22 hydrocarbons (70.0%) and minimum selectivity of light hydrocarbons (13.3% for CH 4 and 7.0% for C 2 –C 4 alkanes). The catalysts were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy with an energy dispersive X-ray spectrometer, temperature programmed desorption and temperature programmed reduction. It was revealed that the superior catalytic performance can be attributed to the large pore size and high dispersion of Co 3 O 4 , which afforded an optimum reducibility and acid site density. [ABSTRACT FROM AUTHOR]

Four compounds, namely, [Zn(H2L)2 ·4H2O] ( 1), [Cu(HL) ·(H2O)] ·H2O ( 2), [Ni3L2(bpy)2 ·12H2O] ·4H2O ( 3), and [Co3L2(bpy)2 ·12H2O] ·4H2O ( 4) [H3L = 4, 4′-[(5-carboxy-1, 3-phenylene)bis(oxy)]dibenzoic acid], were synthesized under solvothermal conditions by employing a semi-rigid aromatic multi-carboxylic acid ligand (H3L) and ancillary nitrogen ligand (bpy = 4, 4′-bipyridine). X-ray diffraction studies revealed that complexes 1, 3, and 4 show zero-dimensional (0D) structures, which were further extended to distinct 3D supramolecular nets by extensive hydrogen-bond interactions. However, in compound 2, 1D chains of square-shaped pores were linked together by HL2- ligands to generate a 2D porous layer along the ac plane. Comparison of the structures indicated that not only the conformation of the functional ligand, but also the ancillary ligand helped in structural determination of the compounds. Compound 1 exhibited solid fluorescence emission originating from an intraligand π→π* transition. Magnetic susceptibility measurements demonstrated that compound 2 exhibited antiferromagnetic coupling between adjacent copper(II) ions, with the corresponding J values of -141.84 cm-1. Furthermore, the thermal behaviors of the complexes 1- 4 were studied by thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Abstract: SAPO-34 molecular sieves were fabricated by a dry gel liquid-phase transport method using morpholine (Mor) or morpholine–tetraethylammonium hydroxide (Mor–TEAOH) as the structure-directing agent (SDA). The prepared samples were characterized by scanning electron microscope (SEM), nitrogen adsorption–desorption, X-ray diffraction (XRD), ammonia temperature-programmed desorption (NH3-TPD), thermo-gravimetric analysis (TG) and Fourier transform infrared spectroscopy (FT-IR). The results indicated that the dry gel liquid-phase transport method is very effective to fabricate SAPO-34 molecular sieves with average crystal size about 0.6μm using Mor–TEAOH as SDA and 3μm using Mor as SDA, respectively. Moreover, the addition of TEAOH is beneficial to produce SAPO-34 with small crystal size. Methanol-to-olefins (MTO) reaction was chosen to test the catalytic performance of as-prepared SAPO-34 catalysts. The prepared SAPO-34 catalyst using Mor–TEAOH as SDA exhibited the excellent catalytic performance in MTO process owing to its small crystal size and high crystallinity. The conversion of methanol and selectivity of ethylene and propylene are up to 100% and 87.9%, respectively. [Copyright &y& Elsevier]

We investigated the isobaric vapor-liquid equilibria (VLE) of the binary system methanol + tetrahydrofuran (THF), the ternary system methanol + THF + 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][NTf 2 ]), as well as methanol + THF + 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][NTf 2 ]) in a modified Othmer still. The results indicated that the ionic liquids ([BMIM][NTf 2 ] and [HMIM][NTf 2 ]) produced a consistent salting-in effect of THF, resulting in the incremental relative volatility of methanol to THF. The experimental data were correlated using the e-NRTL model, and the parameters were obtained with a good consistency. The ionic liquids even eliminated the azeotropic phenomenon when the mole ratio of [BMIM][NTf 2 ] was up to 0.173 and [HMIM][NTf 2 ] up to 0.128 as calculated by the e-NRTL model. [HMIM][NTf 2 ] had a stronger effect on the separation of azeotropic mixtures than [BMIM][NTf 2 ] did. [ABSTRACT FROM AUTHOR]

A series of novel l-ascorbyl fatty acid esters were synthesized by catalization of Novozym® 435 under ultrasonic irradiation and characterized by infrared spectroscopy, electrospray ionization mass spectra, and nuclear magnetic resonance. Their properties especially antioxidant activity and stability were investigated. The results showed that the reducing power, the scavenging activity of hydroxyl radical and 2,2-diphenyl-1-picrylhydrazyl radical were decreased with the increase of the number of carbon atoms in fatty acid. The hydroxyl radical scavenging activity and reducing power of l-ascorbyl saturated fatty acid esters were better than that of tert-butylhydroquinone. The induction period in lipid oxidation of l-ascorbyl saturated fatty acid esters and tert-butylhydroquinone were longer than that of l-ascorbyl unsaturated fatty acid esters and l-ascorbic acid both in soybean oil and lard. Besides, the l-ascorbyl fatty acid esters showed different stabilities in different conditions by comparing with l-ascorbic acid, and the l-ascorbyl saturated fatty acid esters were more stable than l-ascorbyl unsaturated fatty acid esters in ethanol solution. [ABSTRACT FROM AUTHOR]

Abstract: In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. [Copyright &y& Elsevier]

Spherical Ba 0.96 La 0.04 TiO 3 powders were synthesized by a wet chemical method-based on a precipitation process, able of controlling uniformity and particle size. After sintering, fine-grain Ba 0.96 La 0.04 TiO 3 ceramics with good dielectric properties were obtained. Different synthesis routes of Ba 0.96 La 0.04 TiO 3 ceramics were used, and their effects on microstructure and dielectric properties were examined. Results showed that the ceramics samples prepared by La 3+ and Ba 2+ added together (abbreviated as, BLT-T) resulted in a mixture of large and small grains, sharp permittivity peaks, and high dielectrics loss. By comparison, another ceramics samples prepared by La 3+ and Ba 2+ added separately (BLT-S) exhibited uniform grain size and broadened/flattened permittivity peaks. The high value of ε r (3255) and low tan δ (0.01) at room temperature and negligible temperature coefficient of capacitance from − 35 to 85 °C suggested the suitability of the above materials for multilayer capacitor applications. [ABSTRACT FROM AUTHOR]

Hierarchical zeolites were synthesized by alkali treatment and their applications in Fischer-Tropsch (FT) synthesis were studied. It was found that alkali treatment not only created hierarchical structure but also could tune cobalt-support interaction. The dissolution of Si by alkali treatment became easier with the increase of Si/Al ratio, and thus the amount of mesopority increased. An optimal Si/Al molar ratio was identified over the zeolite with Si/Al ratio of 80, which was found to be superior to other catalysts in terms of better diesel selectivity and lower CH selectivity due to its relatively narrow bimodal pore size distribution and moderate cobalt-support interaction. Meanwhile alkali treatment could enhance cobalt-support interaction via the formation of ɑ-SiO Co/MZ-120 catalyst showed the lowest FT activity and higher CH selectivity due to the increase of such new phase. [ABSTRACT FROM AUTHOR]

Based on a promising process of biomass to liquid (BTL) fuels, a pilot-scale plant including gasification, direct synthesis of dimethyl ether (DME) and DME to gasoline was developed. The evaluations of the designed facilities and the optimization of the operation parameters for the whole system were carried out. The several running tests demonstrated the feasibility of converting biomass to high octane gasoline in the developed pilot plant. The adopted critical components of the facilities were verified and the anticipated design goal was achieved. The operating results showed that both the pressure and gas hourly space velocity (GHSV) not only influenced the CO conversion and the DME yield, but also had a significant effect on the manipulation of the reaction heat in the adiabatic reactor. High pressure and low GHSV favored the high CO conversion and the DME yield. Considering CO conversion and temperature controlling of the adiabatic reactor, the optimized pressure and GHSV of the synthesis process were 2.2–2.5 MPa and 1200 h −1 , respectively. The per-pass conversion of CO and the production capacity of gasoline were about 45% and 4.4 kg/h, respectively under this condition. [ABSTRACT FROM AUTHOR]

A series of novel benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives were designed and synthesized. The biological activities of these derivatives were then evaluated as potential antitumour agents. These compounds were assayed for growth-inhibitory activity against HCT116, MCF-7 and HepG2 cell lines in vitro. The IC 50 values of compounds A 1 and A 7 against the cancer cells were 0.06–3.64 μM and 0.04–9.80 μM, respectively. Their antiproliferative activities were significantly better than that of 5-Fluorouracil (IC 50 : 56.96–174.50 μM) and were close to that of Paclitaxel (IC 50 : 0.026–1.53 μM). The activity of these derivatives was over 100 times more effective than other reported structures of chalcone analogues (licochalcone A). A preliminary mechanistic study suggested that these compounds inhibit p53-MDM2 binding. Compounds A 1 , A 7 and A 9 effectively inhibited tumour growth in BALB/c mice with colon carcinoma HCT116 cells. The group administered 200 mg/kg of compound A 7 showed a 74.6% tumour growth inhibition with no signs of toxicity at high doses that was similar to the inhibition achieved with the 12.5 mg/kg irinotecan positive control (70.2%). Therefore, this class of benzimidazole-2-subsituted phenyl or pyridine propyl ketene derivatives represents a promising lead structure for the development of possible p53-MDM2 inhibitors as new antitumour agents. [ABSTRACT FROM AUTHOR]

An error test and compensation method of infrared guidance hardware-in-the-loop system by self-calibration device and flight motion simulator was proposed. The optical system of the unit under test and infrared scene projector were combined into a synthesis optical system. After the pupil function of synthesis optical system reconstructed, Fourier-optics method and ray-tracing method were adopted to analyze the effect on PSF and MTF caused by “offset error” and “tilt error”. The analysis results showed that the MTF were higher than 0.4 in spatial frequency of 30 (lp/mm), when the system has offset error below 5 mm and tilt error below 0.3°. However, the tilt error would affect the position of the PSF, and it should be eliminated. To eliminate the tilt error, a self-calibration device was designed, and the tilt error compensation method by adjusting the flight motion simulator was described. Finally, the experiment results showed that the accuracy of the simulation results was improved obviously after the compensation. [ABSTRACT FROM AUTHOR]

The BMP pathway is a promising new target for the design of therapeutic agents for the treatment of low bone mass. To enrich our understanding of SAR and based on our previously concluded structure–effect relationship, 23 derivatives were prepared in this work. The synthesis, up-regulating activities on BMP-2 expression, and bone loss prevention efficacies of these compounds in rats with glucocorticoid-induced osteoporosis are presented. The bone histology of the tested rats assessed through light microscopy showed that compounds 1 , 21 , 35 , and 38 significantly increased the trabecula compared with the model group, and the trabecula of the groups treated with 8a was similar to that obtained with raloxifene and alfacalcidol. The compounds exhibited potential for development as anabolic agents. [ABSTRACT FROM AUTHOR]

Abstract: The Ho3+/Yb3+ co-doped NaGd(WO4)2 phosphors with different concentrations of Yb3+ were prepared by a facile hydrothermal route. X-ray diffraction and scanning electron microscopy were used to study the structure of the samples. The upconversion (UC) emission spectra of the samples were measured under 980nm excitation with different pumping power. Intense red luminescence at 625–675nm, weak blue luminescence at 458–492nm, green luminescence at 523–565nm and near infrared luminescence at 736–770nm emitted by Ho3+ were observed, and their emission intensities changed with the Yb3+ concentration. The transition mechanisms of the UC luminescence were also discussed. [Copyright &y& Elsevier]

Abstract: A novel class of small-molecule inhibitors of MDM2–p53 interaction with a (E)-3-benzylideneindolin-2-one scaffold was identified using an integrated virtual screening strategy that combined both pharmacophore- and structure-based approaches. The hit optimisation identified several compounds with more potent activity than the hit compound and the positive drug nutlin-3a, especially compound 1b, which exhibited both the highest binding affinity to MDM2 (K i = 0.093 μM) and the most potent antiproliferative activity against HCT116 (wild type p53) cells (GI50 = 13.42 μM). Additionally, 1b dose-dependently inhibited tumour growth in BALB/c mice bearing CT26 colon carcinoma, with no visible sign of toxicity. In summary, compound 1b represents a novel and promising lead structure for the development of anticancer drugs as MDM2–p53 interaction disruptors. [Copyright &y& Elsevier]

An abstract of the article "The first example of glucose-containing carbene broensted acid synthesis and catalysis: Efficient synthesis of five substituted tetrahydropyridines,: by Q.-J. Zhou and colleagues is presented.