Heteroaromatic organic compound with conjugated multi-carbonyl as cathode material for rechargeable lithium batteries

The heteroaromatic organic compound, N,N\u27-diphenyl-1,4,5,8-naphthalenetetra-carboxylic diimide (DP-NTCDI-250) as the cathode material of lithium batteries is prepared through a simple one-pot N-acylation reaction of 1,4,5,8-naphthalenetetra-carboxylic dianhydride (NTCDA) with phenylamine (PA) in DMF solution followed by heat treatment in 250 °C. The as prepared sample is characterized by the combination of elemental analysis, NMR, FT-IR, TGA, XRD, SEM and TEM. The electrochemical measurements show that DP-NTCDI-250 can deliver an initial discharge capacity of 170 mAh g-1 at the current density of 25 mA g-1. The capacity of 119 mAh g-1 can be retained after 100 cycles. Even at the high current density of 500 mA g-1, its capacity still reaches 105 mAh g-1, indicating its high rate capability. Therefore, the as-prepared DP-NTCDI-250 could be a promising candidate as low cost cathode materials for lithium batteries

Genome-Wide Identification and Expression Profiling of the TCP Family Genes in Spike and Grain Development of Wheat (Triticum aestivum L.)

The TCP family genes are plant-specific transcription factors and play important roles in plant development. TCPs have been evolutionarily and functionally studied in several plants. Although common wheat (Triticum aestivum L.) is a major staple crop worldwide, no systematic analysis of TCPs in this important crop has been conducted. Here, we performed a genome-wide survey in wheat and found 66 TCP genes that belonged to 22 homoeologous groups. We then mapped these genes on wheat chromosomes and found that several TCP genes were duplicated in wheat including the ortholog of the maize TEOSINTE BRANCHED 1. Expression study using both RT-PCR and in situ hybridization assay showed that most wheat TCP genes were expressed throughout development of young spike and immature seed. Cis-acting element survey along promoter regions suggests that subfunctionalization may have occurred for homoeologous genes. Moreover, protein–protein interaction experiments of three TCP proteins showed that they can form either homodimers or heterodimers. Finally, we characterized two TaTCP9 mutants from tetraploid wheat. Each of these two mutant lines contained a premature stop codon in the A subgenome homoeolog that was dominantly expressed over the B subgenome homoeolog. We observed that mutation caused increased spike and grain lengths. Together, our analysis of the wheat TCP gene family provides a start point for further functional study of these important transcription factors in wheat

Adsorptive removal of Ni and Cd from wastewater using a green longan hull adsorbent

The adsorptive removal of Ni 2+ and Cd 2+ at concentrations of approximately 50 mg L −1 in wastewater is investigated using an agricultural adsorbent, longan hull, and the adsorptive mechanism is characterized. The maximum adsorption capacity of approximately 4.19 mg g −1 Cd 2+ was obtained under the optimized conditions of room temperature, pH 5.0, and a solid-to-liquid ratio of 1:30 in approximately 15 min. For Ni 2+ , the maximum adsorption capacity of approximately 3.96 mg g −1 was obtained at pH 4.7 in approximately 20 min. The adsorption kinetics for both metal ions on the longan hull can be described by a pseudo second-order rate model and are well fitted to the Langmuir adsorption isotherm. The adsorption mechanism of the longan hull to Ni 2+ and Cd 2+ ions is shown to be a monolayer adsorption of metal ions onto the absorbent surface. Thereinto, the longan hull adsorbent contains N–H, C–H, C=O, and C=C functional groups that can form ligands when loaded with Ni 2+ and Cd 2+ , which reduces the fluorescence of the dried longan hull material

Discovery and development of natural heat shock protein 90 inhibitors in cancer treatment

Heat shock protein 90 (Hsp90) is a highly conserved molecular chaperone that plays a vital role in the signal transduction of cancers. Hsp90 inhibitors are able to inhibit Hsp90 or the complex of Hsp90 and co-chaperones resulting in the degradation of Hsp90-dependent client proteins through the ubiquitination-proteasome pathway, thereby leading to the growth inhibition of tumor cells. This review will briefly discuss the molecular structure and biological function of Hsp90, and focus on a summary of recent progress in the development and testing of natural Hsp90 inhibitors and their different means by which they interact with Hsp90

Electrochemical double-layer capacitor performance of novel carbons derived from SAPO zeolite templates

Mesoporous carbons have been synthesized using template method by polymerizing and then carbonizing carbon precursor of sucrose accommodated in novel templates of SAPO-11 and SAPO-34 after the removal of templates with NaOH solution (50 vol.% ethanol-50 vol.% H2O). High surface areas and excellent eletrochemical properties of the mesoporous carbons were identified by the Brunauer-Emmett-Teller method, cyclic voltammetry, electrochemical impedance spectroscopy and constant current charge-discharge tests. The surface areas of the sample carbons are the range of 950-975 m2/g, with a narrow pore size between 3.8 and 11.0 nm. The sample carbon derived from SAPO-11 exhibits better electrochemical performance over the one from SAPO-34, with the specific capacitance of 154.8, 113.5 F/g them, respectively, measured in 1 M KOH aqueous solution at the loading current density of 0.25 A/g

The Investigations of Surface Treatment Methods and Characterization of Oxide Films on AB_5based Metal Hydride Electrodes Ⅰ. New Nirich treatment methods and photoelectrochemical characterization of oxide films

发展了两种贮氢合金表面处理新方法．光电子能谱和循环伏安实验表明，经过处理后得到了富镍表面层，可提高电极的反应性能．采用光电化学方法对不同处理的电极表面由动电位氧化形成的氧化膜进行了表征，分别观察到与表面膜吸附氢氧化和氧化还原反应有关的阳极光电流和阴极光电流，同时依照电极在循环过程中的光电流变化区分了两种处理方法所得到的表面层抗氧化性能之差异．通过粉末单电极初期充放电实验，证实了电极经方法１处理以后其放电性能得到提高．Two simple and efficient surface treatment methods for AB_5type hydrogen storage alloys were developed. The results of X-ray photoelectron spectroscopy (XPS) and cyclic voltammetric (CV) experiments showed that the hydrogen storage alloys treated by two different methods had Nirich surface layer so that the performances of the electrodes were improved after treatment. The characterization of the oxide films which formed on the surface of electrodes through potentiodynamic oxidation with the help of photoelectrochemical microscopy (PEM) were done. The anodic photocurrent and the cathodic photocurrent related to the oxidation of hydrogen and the reduction of oxygen on the surface layer were observed in different potential regions respectively. Furthermore, it was found that the capability of oxidationresist of alloy depends on the surface treatment procedure, and it was shown that the capability of oxidationresist of alloy treated by the 1st method was better than the second. Finally, it was demonstrated that the discharge performance of the electrode treated by the 1st method was greatly improved.作者联系地址：厦门大学化学系固体表面物理化学国家重点实验室Author's Address: State Key Lab. for Phy. Chem. of the Solid Sur., Inst. of Phy, Chem, Dept. of Chem., Xiamen Univ., Xiamen 36100

Paper-Based Composite Separator with Thermotolerant and Flame-Retardant Sodium Silicate Sheath for High-Performance Sodium-Ion Batteries

In comparison to the well-known separator of lithium-ion batteries (LIBs), there are unique characteristics and requirements for the separator of sodium-ion batteries (SIBs) to affect the electrochemical performance and safety. In this work, a composite separator (AP@NSIO) is successfully fabricated by constructing a fully encapsulated sodium silicate (NSIO) ceramic sheath on the fiber surface of a low-cost, recyclable airlaid paper (AP) matrix using a facile solution immersion method. Due to the comprehensive coating of sodium silicate on the matrix fiber, the prepared AP@NSIO separator not only has excellent mechanical strength and remarkable wettability but also maintains thermal dimensional stability at 250 °C and is nonflammable in flames. Moreover, the AP@NSIO separator exhibits a high porosity of ∼50.6%, an electrolyte uptake of ∼298.9%, an ion conductivity of 2.02 mS cm–1, and a sodium-ion transfer number of 0.91. The Na3V2(PO4)3 (NVP)|AP@NSIO|Na battery has an excellent capacity retention of 94.2% (96.8 mAh g–1) after 300 cycles at a high current density of 5C and maintains almost 100% Coulombic efficiency. These results indicate that the AP@NSIO separator is a potential candidate for application in safe and high-performance SIBs, and a strategy is provided for designing functional separators for SIBs

Functional composite polymer electrolytes with imidazole modified SiO2 nanoparticles for high-voltage cathode lithium ion batteries

Poly(vinylidene fluoride-co-hexafluoro-propylene) doped with imidazole-modified silica nanoparticles (Z-SiO2) is coated in a polyethylene substrate to form a functional composite polymer electrolyte (PVDF-HFP-(Z-SiO2)/PE-based CPEs) and used for high voltage LiNi0.5Co0.2Mn0.3O2 cathode lithium-ion batteries (LIBs). The imidazole-based modified SiO2 nanoparticles are first prepared via a distillation precipitation polymerization. The composite separators with 30 wt% Z-SiO2 nanoparticles prepared via a dip-coating process exhibits a porous and uniformly dispersed morphology and enhanced performance, including excellent electrolyte uptake (310%), high ionic conductivity of 1.03 mS cm−1, and oxidative decomposition voltage up to 4.75 V. More importantly, a stable cathode electrolyte interphase (CEI) layer can be formed, endowing the Li/PVDF-HFP-(Z-SiO2)/PE-based CPEs/LiNi0.5Co0.2Mn0.3O2 (NCM523) cells superior cycling stability and rate capability (169 mAh g−1, 81.9%) under when the charge cut-off voltage increased to 4.5 V, which is higher than that assembled with PE separator (160 mAh g−1, 40.8%). These results demonstrate that the Z-SiO2 nanoparticles not only act as the fillers of the CPEs but also are water/acid scavengers in favor of the formation of a stable CEI film, which promotes the cycling performance and rate capability of high voltage NCM523 cathode and reveals promising prospect for practical applications in LIBs at high voltage operation