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Carbon modified lithium titanate (Li4Ti5O12) anode nanocrystals for Li-ion batteries were synthesized by directly treating the titanium alkoxide and lithium acetate ethanol solution via the Reaction under Autogenic Pressure at Elevated Temperature (abbreviated to RAPET). The mixture of the liquid precursors decomposed during the RAPET process and then reacted in situ and transformed into carbon-modified Li4Ti5O12 anode nanocrystals. The organic moieties in the titanium alkoxide and the lithium salt provided both the oxygen and carbon for the synthesis. The resulting products were characterized by X-ray diffraction (XRD), elemental analysis, scanning electronic microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), nitrogen adsorption–desorption measurements, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge–discharge testing. The influences of the titanium alkoxide precursors, i.e. the length of the alkoxy group, on the properties of the final products and the presence of the in situ resulting carbon on the electrochemical performance have been investigated. [ABSTRACT FROM AUTHOR]

A series of N-aryl or N-methyl substituted bisimidazolium dichloride or dibromide salts with different alkyl bridge lengths (n = 1–4) have been synthesized starting from N-arylimidazoles or N-methylimidazoles with dialkyl bromides or the less expensive but less reactive dialkyl chlorides under solvent-free conditions. This green protocol provided most bisimidazolium chloride and bromide salts in good yields, and the reaction time was shortened to a few hours. In two examples, we showed either bisimidazolium dichloride (1a) or dibromide salt (3c) can be easily converted to the corresponding dihexafluorophosphate salt (1a′ or 3c′) in near quantitative yield. [ABSTRACT FROM PUBLISHER]

An efficient C-N coupling reaction of aryl chlorides or bromides with imidazole was successfully performed with cheap and commercially available catalytic system Cu(I)/HMTA. Both aryl bromides and aryl chlorides have been effectively catalyzed by Cu/HMTA, giving products in moderate to good yields. Moreover, aryl halides bearing either electron-withdrawing groups or electron-donating groups could be used in the reaction. [image omitted] [ABSTRACT FROM AUTHOR]

Abstract: Fe3+–Nb5+ co-doped SnO2 was prepared at 1200°C by a simple chemical co-precipitation method. The Sn1−2 x Fe x Nb x O2 solid solutions kept cassiterite structure in the range of 0

La1−xSrxMnO3 (x=0.3) (LSM) nanoparticles were prepared by a sonication-assisted coprecipitation method. The coprecipitation reaction is carried out with ultrasound radiation. Lower sintering temperatures are required for the sonication-assisted product. Fully crystallized LSM with an average particle size 24 nm is obtained after the as-prepared mixture is annealed at 900 °C for 2 h. Magnetic properties indicate that the transition temperature from the paramagnetic to ferromagnetic state of the sample is quite sharp and occurs at 366 K for samples annealed for 2 h at 900 and 1100 °C. [Copyright &y& Elsevier]

A flexible, self‐floating W18O49/carbon foam composite is fabricated by calcining melamine foam with W18O49 as an adsorbate in N2 atmosphere. This self‐floating property is simply realized by a carbonization process other than the complicated surface modification process. The simple synthesis procedure helps to increase not only the solar absorption but also the retention of W18O49 in the porous net structure. This composite absorbs almost the whole solar spectrum and generates localized heat at the surface, which is beneficial for water evaporation. Its water evaporation rate is 6.6 times higher than that of pure water. It has a stable cyclic performance over ten cycles under the illumination of simulated sunlight (500 W Xe lamp). Its flexibility makes it easy to reuse and transfer, which is evaluated by the bending deformation test. The W18O49/carbon foam composite is a prospective material in solar energy conversion field, and the preparation procedure is feasible to scale‐up. [ABSTRACT FROM AUTHOR]

A selective extraction process for recovering vanadium (IV) over chromium was proposed with use of a mixed extractant consisting of di(2-ethylhexyl) phosphate (D2EHPA) and tri-n-butyl phosphate (TBP). The influence of various factors, which included the initial aqueous pH value, the concentration of leach solution and D2EHPA, phase ratio (O/A), extraction equilibrium time and extraction temperature in the extraction process on the separation of V and Cr was investigated. Under the condition of the optimum extraction, vanadium extraction was above 94.0%. Meanwhile, under the optimum stripping conditions, the vanadium stripping was above 93.0% utilizing 1.5 mol/L sulfuric acid as the effective stripping reagent. The regeneration and reusability of the loaded organic phases after stripping were discussed. In addition, continuous three-stage extraction and stripping strategy indicated that the aggregate loss of vanadium was 0.885% and that the purity of vanadium was more than 99.9%. Under the condition of the optimum precipitation, when the pH value of the stripping solution was adjusted to 7.0 with ammonia water, the precipitation efficiency reached 99.93%. The calcination conditions (above 680 °C in air) were finally determined by TG-DTA and TG-MS experiments, and the V2O5 obtained by calcination was characterized by XRD. Additionally, a method for detecting impurity elements in vanadium matrix without interference was established. The recovery technology has practical significance in enlarging production scale, reducing specific energy consumption and cost, and realizing automatic control in vanadium leaching process. [ABSTRACT FROM AUTHOR]

The design of graphene quantum dots (GQDs)-aptamer bioconjugates as the new sensing platform is very important for developing high-sensitivity fluorescent biosensors; however, achieving new bioconjugates is still a great challenge. Herein, we report the development of a new high-sensitivity fluorescent aptasensor for the detection of ochratoxin A (OTA) based on tuning aggregation/disaggregation behavior of GQDs by structure-switching aptamers. The fluorescence sensing process for OTA detection involved two key steps: (1) cDNA-aptamer (cDNA, complementary to part of the OTA aptamer) hybridization induced the aggregation of GQD (fluorescence quenching) after cDNA was added into the GQDs-aptamer bioconjugate solution, and (2) the target of OTA triggered disaggregation of GQD aggregates (fluorescence recovery). Such new fluorescent sensing platform can be used to monitor OTA with a linear range of 0 to 1 ng/mL and very low detection limit of 13 pg/mL, which is among the best in all the developed fluorescent nanoparticles-based sensors. Such sensing strategy is also successful in analyzing OTA in practical red wine sample with 94.4-102.7% of recoveries and relative standard deviation in the range of 2.9-5.8%. The present works open a new way for signaling the target-aptamer binding event by tuning aggregation/disaggregation behavior of GQDs-bioconjugates. [ABSTRACT FROM AUTHOR]

A novel Fenton reagent, chalcopyrite CuFeS nanocrystals (NCs) with an average diameter of 10.6 ± 1 nm are synthesized by a facile solution phase method in a standard Schlenk Line, and they can efficiently degrade organic dyes (methylene blue, rhodamine B and rhodamine 6G) aqueous solution (100 mg L) within 1 min. XRD and TEM have been carried out to determine the crystal information, size, and shape of CuFeS NCs. The degradation process is investigated by UV-Vis spectroscopy, and its advantage is illustrated by comparing with bulk chalcopyrite. X-ray photoelectron spectroscopy is used to discuss its degradation mechanism. Based on this Fenton reagent, CuFeS NCs/biomass composite degradation column is made using sawdust as substrate, and it can efficiently degrade organic dyes continually (the total amount of organic dyes degraded by the column are 8.67, 8.44, and 8.64 times the amount degraded by pure CuFeS NCs, respectively). [ABSTRACT FROM AUTHOR]

Protein phosphorylation regulates and controls protein activity and function, which is the most basic and important part in organisms' lives. However, the low abundance and ionization inhibition of phosphopeptides make it difficult to understand and analyze the protein phosphorylation mechanism. In this study, we synthesize a core‐shell structured magnetic Ti4+‐based immobilized metal ion affinity chromatography material for highly selective enrichment of phosphopeptides. The introduction of negatively charged carbon layer increases the specific surface area and avoids loss of the immobilized Ti4+ during sample loading and washing. The synthesized magnetic superhydrophilic extractant is employed to separate and enrich phosphopeptides from standard protein digests coupled with MALDI‐TOF MS. It exhibits excellent enrichment performance of high selectivity (1 : 2000 molar ratio of β‐casein and BSA), sensitivity (low detection limit of 4 fmol) and preferable reusability (at least 12 times) as well as excellent adsorption capacity of 142.5 mg ⋅ g−1 and high recovery rate of 85.6 %. Moreover, sixteen phosphopeptides and four endogenous phosphopeptides can be accurately identified from non‐fat milk and human serum, further indicating the great potential and bright application in phosphoproteomics analysis. [ABSTRACT FROM AUTHOR]

Abstract: Mg-doped LaCoO3 particles were prepared in various particle sizes via a modified sol–gel method using excess MgO as pinning particles. The adsorbed oxygen species of the products were studied by XPS, TPD-O2 and TPR-H2. The amount of adsorbed oxygen varied with changes in average particle size and had an important effect on the catalytic activity towards CO oxidation. XPS and TPD-O2 results indicated that there were two kinds of surface oxygen species and that the relative ratio of the surface adsorbed oxygen to lattice oxygen increased with an increasing BET surface area. The catalytic activities of Mg-doped LaCoO3 particles were clearly enhanced with the increase of surface area and the amount of adsorbed oxygen. [Copyright &y& Elsevier]