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• CZ48 was incorporated into PLA microbubbles via a double emulsion technique. • The encapsulation efficiency and drug-loading content were ˜85.73% and 26.07%. • The half-life time of CZ48 and CPT of CZ48-loaded microbubbles was enhanced. • Controlled release of CZ48–loaded microbubbles was achieved in vitro and in vivo. CZ48, a prodrug of camptothecin (CPT) with derivative resistant to lactone hydrolysis, suffers from limited application for cancer treatment due to poor water-solubility, thus causing its low bioavailability and absorption in vivo. To echo this problem, CZ48 was incorporated into poly (lactic acid) (PLA) microbubbles via a double emulsion technique (W/O/W), and the successful loading was confirmed by X-ray diffraction (XRD) patterns and confocal laser scanning microscope (CLSM). The obtained CZ48-loaded microbubbles had a diameter ranging from 0.5 to 6.7 μm, and the encapsulation efficiency and drug-loading content were as high as 85.73 ± 2.41% and 26.07 ± 0.76%, respectively. The in vitro drug release demonstrated that only about 55% of CZ48 was released for CZ48-loaded PLA microbubbles in 48 h. In contrast, over 90% of CZ48 was released for free CZ48 crystals sample in only 5 h. Besides, in vivo pharmacokinetic studies further revealed that the availability of both CZ48 and its metabolite CPT were obviously enhanced after the incorporation of CZ48 into PLA microbubbles. To be noted, the value of AUC 0-∞ of the CZ48-loaded microbubbles was about 5-fold higher than that of free CZ48 suspension, implying a much higher anticancer effect of the CZ48-loaded microbubbles. The half-life time (T 1/2) of both CZ48 and CPT of the CZ48-loaded microbubbles were also significantly longer than that of the free CZ48, indicating a delayed release time for the microbubbles. Hence, this work promotes a promising drug carrier system for the controlled release of CZ48 as well as other drugs with poor water-solubility. [ABSTRACT FROM AUTHOR]

The understanding and tailoring of the electrochemistry of graphite is of significant industrial importance. We develop a method of etching pits into the basal planes of highly oriented pyrolytic graphite (HOPG) by electrolysis. The etching of HOPG was realized by performing electrochemical reactions at alternating potentials at room temperature, and the resulting membranes are characterized using atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectra, X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectrscopy, and cyclic voltammetry. Etching only occurs when the electrolysis at negative bias is followed by a brief switch to a positive bias. The size of the etched pits can be tuned by varying the applied potential and reaction time, with deeper pits formed with increased redox cycles and reaction time. Cyclic voltammetry reveals that the electrochemical performance is enhanced greatly as etching progresses due to exposure of edge sites. For its ease of application, efficiency and low cost, our wet etching approach has great promise as a method to develop high active electrodes and nanoporous membranes at large scales for various industrial applications. [ABSTRACT FROM AUTHOR]

A mechano-chemical method was used to synthesize solid solution Na(BH 4 ) 1-x Br x with 0 ≤ x ≤ 1. Samples with compositions of x ≤ 0.333 were annealed, in order to form a single phase material. Bromide substitution leads to smaller unit cell size and lower temperature and enthalpy of the order-disorder phase transition of NaBH 4 . There is a linear relation between the amount of substitution, the temperature, the enthalpy and the kinetics of the phase transition. This linear relation between enthalpy and amount of substitution can be expressed by the function ΔH = −6.268x + 1.206 where x is the amount of substitution and ΔH is the enthalpy. [ABSTRACT FROM AUTHOR]

We report the synthesis of CdS nanospheres and reduced graphene oxide (rGO) hybrid nanocomposites (CdS@rGO) under hydrothermal conditions. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) are employed to confirm the structures and morphologies of sphere-like CdS@rGO nanocomposites. The electrocatalytic activity for the reduction of triiodide and chemical stability for CdS@rGO composites are studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and Tafel plots. The short-circuit current density ( J sc ), open-circuit voltage ( V oc ) and fill factor ( FF ) are 14.81 mA cm −2 , 0.76 V and 0.656, respectively. Most importantly, these CdS@rGO materials are used as the counter electrode (CE) of dye-sensitized solar cells (DSCs), and their conversion efficiency of this CE reaches 7.39%, which is comparable to the conventional platinum counter electrode (7.44%) under the same test conditions. Meanwhile, the CdS@rGO CE possesses the robust stability and the cost-effective performance in addition to the high power conversion efficiency. [ABSTRACT FROM AUTHOR]

A novel bifunctional Ti–Fe kaolinite composite with excellent adsorption and photocatalytic properties was synthesized by a simple precipitation method. X-ray diffraction analysis and high-resolution transmission electron microscope analysis confirmed the existence of rutile phase TiO 2 and amorphous iron in the composite. The specific surface area of the Ti–Fe kaolinite composite is 5.5 times higher than that of the original kaolinite. The composite was used as an adsorbent as well as photocatalyst for Cr(VI) removal. The results indicate that the low pH is favorable to the Cr(VI) removal by the composite and the removal rate of Cr(VI) reached 87% at pH 3.0. Visible light irradiation obviously increased the removal of Cr(VI) by the composite and greatly shortened reaction equilibrium time, which may be attributed to the photocatalytic reduction of Cr(VI) to Cr(III) by TiO 2 associated with simultaneous redox cycle of Fe(III)/Fe(II). Various common co-existing ions did not show obvious effects on the removal of Cr(VI) by the composite. The composite exhibited very high stability for the Cr(VI) removal. The adsorption models and thermodynamics of Cr(VI) onto the composite were studied. [ABSTRACT FROM AUTHOR]

Five silver(I) complex of 4-amino-3,5-dipropyl-4 H-1,2,4-triazole (4-NH-3,5-Prtz) or 4-amino-3,5-dibutyl-4 H-1,2,4-triazole (4-NH-3,5-Butz), namely [Ag(4-NH-3,5-Butz)(NO)] ( 1), [Ag(4-NH-3,5-Prtz)(NO)](NO) ( 2), [Ag(4-NH-3,5-Prtz)](ClO) ( 3), [Ag(4-NH-3,5-Prtz)](CFSO) ( 4) and [Ag(4-NH-3,5-Butz)](BF) ( 5), have been prepared and structurally characterized by X-ray single crystal diffractions. Based on the structural data, a possible mechanism for the formation of Agtz cluster has been proposed, involving the formation of a dimer of dimer-(Agtz), followed by the replacement of counterions by two additional triazoles. [ABSTRACT FROM AUTHOR]

Highlights: [•] A series of fcc structured equiatomic solid solutions were designed. [•] The solid solution limit in multi-component equiatomic alloys was explored. [•] Topological instability sets the solid solution limit. [•] Decomposition occurs when the lattice strain reaches a critical value of 0.018. [ABSTRACT FROM AUTHOR]

Two new three-dimensional 12-connected metal–organic coordination polymers, [Zn2(bptc)(H2O)]·C2H5OH·H2O (1) and [Cd4(bptc)2(bbi)(H2O)]·H2O (2) (H4bptc=biphenyl-2,5,2′,5′-tetracarboxylic acid, bbi=1,1′-(1,4-butanediyl)bis(imidazole)), have been solvothermally synthesized and structurally characterized by single crystal X-ray diffraction analyses. All compounds are also characterized by elemental analyses, IR spectra, thermogravimetric (TG) analyses and X-ray powder diffraction (XRD). Topological analysis indicates that both 1 and 2 are 12-connected frameworks with fcu topology, which are based on cuboid cage and rob-like {Cd3} subunit as 12-connected nodes, respectively. Furthermore, the luminescence properties of the two compounds were discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract: Graphene oxide–Fe2O3 (GO–Fe2O3) hybrid material was synthesized as a heterogeneous catalyst for photo-Fenton degradation of organic contaminants by an easy and scalable impregnation. X-ray diffraction analysis and high-resolution transmission electron microscope analysis confirm the existence of the Fe2O3 nanoparticles in the GO–Fe2O3 catalyst. Fourier transform infrared spectroscopy analysis proves that the combination of Fe2O3 and GO sheet is due to the metal–carbonyl coordination. The catalytic activities of the GO–Fe2O3 catalyst were evaluated by the degradation of Rhodamine B and 4-nitrophenol under visible light irradiation (>420nm) in the presence of hydrogen peroxide. The results show that the catalyst exhibited excellent catalytic property at a wide pH range of 2.09–10.09 and stable catalytic activity after seven recycles, which could be attributed to the synergetic effects of the adsorptive power of GO and the hydroxyl radicals produced by heterogeneous photo-Fenton reactions. The present results suggest that the GO–Fe2O3 hybrid material can act as an efficient heterogeneous catalyst for degradation of organic contaminants, which may provide insight into the design and development of high-efficiency visible-light photocatalyst for water treatment. [Copyright &y& Elsevier]

The fly ash sample was characterized by size fraction, X-ray diffraction, contact angle measurements and X-ray fluorescence. The function of a new type of frother (KD) which can produce more stable foam than conventional frothers was studied. The effect of the column flotation operating variables on the removal of unburned carbon from the fly ash was also systematically examined. Within the range studied, the optimum frother dosage is 400 g/t, superficial gas velocity is 1. 8 cm/s, froth thickness is about 150-200 mm and circulating pressure is 0. 22 MPa. The results indicate that Cyclonic-Static Micro-bubble Flotation Column (FCSMC ) technique is effective in removing the unburned carbon from coal fly ash. Under the optimized conditions, a cleaning ash with 3. 15% LOI (Loss on Ignition) and 91. 88% RUC(Removal Rate of Unburned Carbon) is obtained. [ABSTRACT FROM AUTHOR]

Abstract: A large new family of rare-earth metal–cadmium–germanides RE2CdGe2 (RE=Y, Pr, Nd, Sm, Gd–Yb) has been synthesized and structurally characterized. All eleven structures have been established from single-crystal X-ray diffraction data and have been found to belong to the tetragonal Mo2FeB2 structure type (ordered ternary variant of the U3Si2 structure type—space group P4/mbm (No. 127), Z=2; Pearson symbol tP10). The structural variations among the three series of isostructural RE2MgGe2, RE2InGe2, and RE2CdGe2 compounds are discussed, as well as the crystal chemistry changes as a function of the decreasing size of the rare-earth metals (lattice constants a=7.176(2)–7.4589(12)Å and c=4.1273(14)–4.4356(13)Å). The experimental results have been complemented by tight-binding linear muffin-tin orbital (TB–LMTO) electronic structure calculations. [Copyright &y& Elsevier]

Abstract: Two new coordination polymers, {[Zn3L2.5(μ 3-OH)(H2O)3]·4H2O} n (1) and [Zn2L1.5(μ 3-OH)(4,4′-bpy)0.5] n (2) (H2L=2,5-bis(4-methylbenzoyl)terephthalic acid, 4,4′-bpy=4,4′-bipyridine), have been hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, TG, PXRD and single crystal X-ray diffraction. Complex 1 possesses a 2D double-layer configuration with 48·62 network constructed with trinuclear zinc(II) clusters and L2− ligands, which extends into a 3D architecture via O–H···O interactions between coordinated water molecules and lattice water molecules. Complex 2 is a uninodal 8-connected 3D framework with a 424·64 network based on tetranuclear zinc(II) clusters as nodes. Moreover, the luminescent properties of complexes 1 and 2 were also investigated. [Copyright &y& Elsevier]

The microstructural features and micromechanical behavior of individual phases in a cast Al0.8CoCrCuFeNi high-entropy alloy (HEA) were characterized by high-resolution scanning electron microscopy and micro-compression tests. Use of neutron diffraction enabled the detection of a new phase which was otherwise unobservable by conventional X-ray diffraction. The identified phase constitution agreed well with the compositional analysis and the micro-compression results. The delicate microscale characterization of individual phase provides new insights for the design of novel HEAs with desirable mechanical properties. [ABSTRACT FROM AUTHOR]

An exceedingly rare 2D → 3D polythreading framework based on (4)-c sql networks with arms, [Cd(L)(bipy) 2 ] n , has been prepared and characterized by X-ray diffraction analysis, and its solid state luminescence has been examined at room temperature. [ABSTRACT FROM AUTHOR]

new approach was developed to prepare high-performance isobutylene-isoprene rubber/swollen organoclay nanocomposites by shear mixing. Compared with traditional melt compounding method, better dispersion of nanoclay layers in rubber matrix was verified through transmission electron microscopy (TEM) and X-ray diffraction (XRD). The nanocomposites also exhibit significantly improved mechanical properties and gas barrier property. As a mechanism, the molecules of organic swelling agent play a vital role in accelerating the diffusion and intercalation of the matrix molecules. [ABSTRACT FROM AUTHOR]

Al-0.05Ga-0.05Sn-0.05Pb-xMg alloys with different Mg content have been prepared. Electrochemical tests including constant current discharge test, current polarization test, electrochemical impedance spectroscopy (EIS) test, and Tafel test are performed. The surface states of the alloys after constant current discharge were analyzed by scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS). X-ray diffraction (XRD) analysis was carried out. We find that different Mg contents have great influence on discharge performance of aluminum alloy anodes by changing the corrosion behavior. The SEM and XRD show that Mg can influence the distribution of corrosion and change the grain size to improve the discharge performance of aluminum anodes. Al-0.05Ga-0.05Sn-0.05Pb-0.1Mg shows the best electrochemical performance due to uniform corrosion and proper grain size. At 800 mA cm−2 constant current discharge, the potential of the aluminum anode can reach − 1.54 V (vs Hg/HgO), and the utilization ratio is over 98%. [ABSTRACT FROM AUTHOR]

In this study, Zn-Ni composite coatings with different Ni contents were deposited on low-carbon steel using Low pressure cold spray (LPCS) method. The morphology, element distribution and phase compositions of powders and as-sprayed coatings were analyzed by using scanning electron microscopy, energy dispersive spectrometer and X-ray diffraction respectively. The corrosion protection mechanism of these composite coatings were investigated using electrochemical technique and their corrosion morphologies. The results show that Zn-Ni composite coatings exhibited a better sacrificial anodic protection and physical shielding effect, where the corrosion resistance of the coating with 10 wt% Ni in the feedstock was best. The corrosion products were mainly composed of Zinc hydroxide Zn(OH) 2 , basic zinc chloride hydrate ZnCl 2 ·4Zn(OH) 2 ·H 2 O, basic zinc carbonate hydrate Zn 4 ·CO 3 (OH) 6 ·H 2 O and the corrosion products is not mixed with alumina. The corrosion process mainly includes active dissolution of zinc, zinc cathodic protection, physical shielding caused by corrosion products. [ABSTRACT FROM AUTHOR]

The FeSSe particles dispersed in the pores of carbon (FeSSe/PC) were prepared using a simple one-pot solid-state method, which were then characterized by XRD, SEM, TEM, XPS, and Raman spectrum techniques. As the anode material for lithium-ion batteries, FeSSe/PC displays an initial discharge capacity as high as 699.5 mAh/g at 0.1 C, and 327.9 mAh/g can be maintained after 200 cycles, much enhanced than those of pure FeSSe. The small particles of FeSSe wrapped in carbon can effectively buffer the volume expansion during charging/discharging to improve the electrochemical performance. [ABSTRACT FROM AUTHOR]

In this paper a new type of autoclaved aerated concrete (ACC) was developed using coal gangue (CGC) and iron ore tailings (ITOs). The material compositions, calcination temperatures of the coal gangue, and the composition of the hydration products were analysed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscope (SEM). The optimal thermal activation temperatures and the activation mechanisms of the calcined coal gangue were also studied. The results indicated that the optimal calcination temperature of coal gangue was approximately 600 °C. The bulk density and compressive strength of AAC samples were approximately 609 kg m −3 and 3.68 MPa, respectively, which passed the requirements of A3.5, B06 level of AAC sample regulated by GB/T 11969-2008. Before the autoclaving, the hydration products in ACC containing CGC and ITOs were tobermorite, hibschite, ettringite, and C–S–H gel; during the autoclaving, ettringite was decomposed and more tobermorite formed coupled with C–S–H gel and hibschite. [ABSTRACT FROM AUTHOR]

Abstract: Hydrothermal reaction of Cd(NO3)2, Co(NO3)2, Na(3-cba) and NaN3 yielded a 3D heterometallic coordination polymer, [Cd(μ5-3-tzba)(μ2-3-cba)(μ3-OH)Co(H2O)] n ·2nH2O 1 (3-H2tzba=3-(5H-tetrazol)benzoic acid and 3-Hcba=3-cyanobenzoic acid), which was characterized by single-crystal X-ray diffraction. The in situ [2+3] cycloaddition reaction of nitrile and azide in presence of Cd(II) salt afforded tetrazolate-based 3-tzba2− ligand. In 1, metal-oxo chains [Cd(μ3-OH)Co] n are linked by 3-tzba2− in an unprecedented μ5-κN1:κN2:κN3:κN4:κO1,O2 coordination mode to form 2D layers, which are further pillared by 3-cba− to generate a 3D open framework encapsulating 1D chiral channels. Variable-temperature magnetic studies show that 1 exhibits antiferromagnetic interactions between Co(II) ions bridged by μ3-OH group. [Copyright &y& Elsevier]

Abstract: Novel magnetic bioactive glass-ceramics (M GC) were synthesized by doping Mg ferrite to wollastonite–fluorapatite-containing glass-ceramics. The phase composition was investigated by XRD. The magnetic property was measured by VSM. The in vitro bioactivity was investigated by simulated body fluid (SBF) soaking experiment. Cell growth on the surface of the material was evaluated by co-culturing osteoblast-like ROS17/2.8 cells with M GC. The results showed that CaSiO3, Ca2MgSi2O7, Ca5(PO4)3F and Fe2MgO4 were the main phases of M GC. Under a magnetic field of 10,000Oe, the saturation magnetization and coercive force of M GC were 7.2emu/g and 175Oe, respectively. After soaking in SBF for 14days, a lot of hydroxyapatite containing CO3 2− was observed on the surface of M GC. The experiment of co-culturing cells with M GC showed that osteoblast-like ROS17/2.8 cells could attach well on the surface of M GC. The material has the potential to be used as thermoseeds for hyperthermia. [Copyright &y& Elsevier]