Intramolecular substitutions of square planar rhodium(Ⅰ) catioriic complexes of ds-dicarbonyl nitrogen coordinated tridentate

Four kinds of square planar cis-dicarbonyl-N,N-bis(2-pyridylethyl)-p-substituted-phenylamino rhodium(Ⅰ) are reported.The changes of their structures were analyzed by XPS,IR and NMR spectroscopy The results show that the weak N→Rh coordinated bond can replace very soon the strong Rh-Cπ back donation bond to form tris-nitrogen coordinated complexes due to the steric effect when the temperature is over 50℃,This reaction is reversible.The bis-nitrogen coordinated structure of the complex recovered when put under the atmosphere of CO     

Meta-analysis of CO2 conversion,energy efficiency,and other performance data of plasma-catalysis reactors with the open access PIONEER database

This paper brings the comparison of performances of CO₂ conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field, organised in an open access online database. This tool is open to all users to carry out their own analyses, but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made, and ultimately to improve the efficiency of CO₂ conversion by plasma-catalys...     

Role of carbon matrix heteroatoms at synthesis of carbons for catalysis and energy applications

The conceptual ideas about the positive effects of N- and O-heteroatoms on the reactivity of carbons in gasification processes, their catalytic activity in electron transfer reactions, as well as the performance of the electrode double-layer supercapacitors due to their electron-donating influence on the π-conjugated system of graphene layers have been developed. This influence decreases both work function and band gap of carbons, and also significantly affects their electron-donating properties. As a result of our investigations based on quantum chemical calculations of model graphene clusters with N- and O-heteroatoms in different positions, prognostic data have been obtained. These data have been confirmed by our experimental results of catalytic activity of corresponding carbons in H2O2 decomposition reaction, their reactivity in gasification processes, and also their performance as electrodes in supercapacitors.     

Discovery of ferrocene-carborane derivatives as novel chemical antimicrobial agents against multidrug-resistant bacteria

Antimicrobial resistance has now become a very serious global public health problem. New drug discovery and development are urgently needed to combat the growing threat of multidrug-resistant (MDR) bacteria. The aim of this study was to explore the potential application of three ferrocene-carborane derivatives as new promising agents to confront the problem of increasing antibiotic resistance. The results of agar diffusion bioassay, minimal inhibitory concentrations (MIC) testing and time-kill assay illustrate their broad-spectrum antimicrobial activities to both American Type Culture Collection (ATCC) control strains and MDR clinical isolates. It is evident that the relevant antimicrobial properties are all in a dose-dependent manner and gradually transform into a bactericidal effect from a bacteriostatic effect with the increasing of the drug concentration. Furthermore, these ferrocene-carborane derivatives have no/little toxic effect on normal cells like HELF cells and lead to little hemolysis at their MICs. This raises the possibility to develop novel antimicrobial drugs using these new ferrocene carborane derivants.     

Design strategies for rechargeable aqueous metal-ion batteries

Rechargeable aqueous metal-ion batteries(AMBs) have attracted extensive scientific and commercial interest due to their potential for cost-effective, highly safe, and scalable stationary energy storage. However, their limited output voltage, inadequate energy density, and poor reversibility of ambiguous electrode reactions in aqueous electrolytes strongly limit their practical viability. This review aims to elucidate the challenges of existing AMBs from the material design to whole device applic...     

Molecularly Imprinted Polymer with Calix[4]arene Derivative for the Recognition of Acetanilide

Two molecularly imprinted polymers binding to analgesic acetanilide were prepared using either dual functional monomers of calix[4]arene derivative and acrylamide or single monomer acrylamide, respectively. The polymers were ground, sieved and investigated by equilibrium binding experiment to evaluate their recognition properties for the template and other substrates. Scatchard analysis showed that homogeneous recognition sites were formed in the imprinted polymer matrix. Our results demonstrated that the polymer using two functional monomers exhibited better selectivity for the template. This study may open new frontiers for the development and application of imprinted polymers, such as drug separation and purification.     

Hydrophobic Interface Cages in Microemulsions: Concept and Experiment Using Tetraphenylethylene-based Double-tailed Surfactant

Although hydrophobic interface regions adjacent to water droplets play a vital role in microemulsion-based studies,their widespread applications have not been explicitly evoked owing to their small spaces.Herein,we designed and synthesized a novel double-tailed anionic surfactant(TPE-di-C8SS)by linking the propeller-shaped tetraphenylethylene(TPE)with two octyl chains and an anionic sulfonate headgroup through a methoxy-butyl spacer.The extra spacer and steric hindrance between rigid TPE groups can create the large cavities in hydrophobic interface regions,which we call the hydrophobic interface cages(HICs).The potentials and advantages of HICs in the easily-prepared TPE-di-C8SS microemulsion have been implemented by comparing the extraction efficiency towards cationic rhodamine B with Aerosol OT(AOT)microemulsion.The results provided solid evidence that HICs rather than water droplets contributed to a higher extraction efficiency.This work not only proposes a concept of HICs but also provides a new perspective of their utilization in microemulsion-based applications.     

The application of sulfur-containing peptides in drug discovery

The purpose of the present review is to focus on the discovery of various sulfur-containing peptides with particular emphasis on their pharmacological mechanisms. This presentation is organized according to the structures of the sulfur-containing peptides.     

Dispersion of Titanium（Ⅳ） Oxide Nanoparticles in Mixed Matrix Membrane Using Octaisobutyl Polyhedral Oligomeric Silsesquioxane for Enhanced CO2/CH4 Separation Performance

Titanium(IV) oxide (TiO2) nanoparticles have been incorporated into mixed matrix membranes (MMMs) to improve gas separation performance. However, TiO2 nanoparticles tend to agglomerate due to high surface energy and van der Waals forces. This leads to precipitation which causes the formation of non-homogeneous MMM morphology. In this study, the effect of octaisobutyl polyhedral oligomeric silsesquioxane (POSS) addition on TiO2/polysulfone MMM was investigated. The aims are to enhance gas separation performance whilst preventing agglomeration of TiO2 nanoparticles. The results demonstrated that inclusion of POSS as dispersant increases MMMs’ CO2/CH4 selectivity and permeance, possibly due to less void formation and more evenly distributed pore structure. For example, synergistic addition of 5 wt% TiO2 and 5 wt% POSS increased the CO2/CH4 selectivity up to 390% compared to MMM without POSS. This is supported by elemental mapping of titanium which revealed that POSS successfully dispersed TiO2 nanoparticles and prevented aggregation. TiO2-POSS/PSf MMMs also retained their favorable thermal stability.     

Synthesis and Crystal Structure of a Mn(II) Complex with Thiosemicarbazone Derivative of Pyridine-3-carbaldehyde Showing Unusual Coordination Mode of Tridentate Thiosemicarbazone

1 INTRODUCTION Heterocyclic thiosemicarbazones as well as their metal complexes have been attracting considerable interest due to their biological activities, such as antiviral, antibacterial, antimalarial, antifungal, and antitumoral activities[1～5]. This prompted us to carry out structural studies of these complexes to provide a basis for understanding their behaviors in living systems. Although quite a number of investigations on the 2-heterocyclic thiosemicarbazones have ap- peared[6…     

Loaded rubber-like materials subjected to small-amplitude vibrations

This paper proposes a constitutive law and a method for characterizing highly preloaded viscoelastic materials subjected to linear （small-amplitude） vibrations. A multiplicative non-separable variables law has been suggested to model the behavior that depends on both stretch and time/frequency. This approach allows splitting the intricate combined test performed simultaneously on both stretch and frequency, generally in a limited experimental domain up to 100 Hz, into two independent tests. Thus, on one hand, the dynamic complex modulus dependent on frequency alone is evaluated on the basis of vibration tests in a large experimental domain up to 100 kHz. On the other hand, energetic parameters are determined from a quasi-static hyperelastic tensile test. The complex modulus, dependent on both stretch and frequency, is then deduced from the results acquired from uncoupled investigations. This work shows that, in extension, the elastic modulus increases with increasing stretch, and the loss factor decreases with increasing stretch; while, in compression, around the material undeformed state, the modulus increases as the stretch increases till a certain value of compression stretch （upturn point depending on material characteristics）, and then the modulus decreases as the stretch increases. Globally, preload rigidifies materials but reduces their damping property. These results closely match a well-known observation in solid mechanics.     

Synthesis of Aryl Allyl Ether in the Recyclable Ionic Liquid [bmim]PF_6

Ionic liquids, especially imidazonium salts, have recently gained recognition as possible environmentally benign alternative chemical process solvents. This is mainly due to their nonvolatile nature, insolubility in some solvents as well as their ability to dissolve a wide range of organic and inorganic materials, allowing the ionic liquids easy recovery and recycling. Examples of their application in organic reactions have been summarized in a number of recent review articles. 1 Aryl allyl et…     

Rhodamine Mechanophore Functionalized Mechanochromic Double Network Hydrogels with High Sensitivity to Stress

Mechanochromic hydrogels, a new class of stimuli-responsive soft materials, have potential applications in a number of fields such as damage reporting and stress/strain sensing. We prepared a novel mechanochromic hydrogel using a strategy that has been developed to prepare dual-network(DN) hydrogels. A hydrophobic rhodamine derivative(Rh mechanophore) was covalently incorporated into a first network as a cross-linker. This first network embedded with Rh mechanophore within the DN hydrogel was pre-stretched. This guaranteed that the stress could be transferred extensively to the Rh-crosslinked first network once the hydrogel was under an applied force. Interestingly, we found that the threshold stress required to activate the mechanochromism of the hydrogel was less than 200 kPa, and much less than those in previous reports. Moreover, because of the excellent sensitivity of the hydrogel to stress, the DN hydrogel exhibited reversible freezing-induced mechanochromism. Benefiting from the sensitivity of Rh mechanophore to both p H and force, the DN hydrogel showed p H-regulated mechanochromic behavior. Our experimental results indicate that the preparation strategy we used introduces sensitive mechanochromism into the hydrogel and preserves the advantageous mechanical properties of the DN hydrogel. These results will be beneficial to the design and preparation of mechanochromic hydrogels with high stress sensitivity, and foster their practical applications in a number of fields such as damage reporting and stress/strain sensing.     

Fine-tuning of polymer photovoltaic properties by the length of alkyl side chains

This paper reports the synthesis and characteristics of a series of alkyl-substituted planar polymers. The physical properties are carefully tuned to optimize their photovoltaic performance. Depending on the length of soluble alkyl side chains which modify the structural order and orientation substantially in polymer backbones, the device performance can be improved significantly. The tuning of HOMO energy levels optimized polymers’ spectral coverage of absorption and their hole mobility, as well as miscibility with fullerene; all these efforts enhanced polymer solar cell performances. The shortcircuit current, Jsc for polymer solar cells was increased by adjusting polymer chain packing ability. It was found that films with well distributed polymer/fullerene interpenetrating network exhibit improved solar cell conversion efficiency. Enhanced efficiency up to 5.8% has been demonstrated. The results provide important insights about the roles of flexile chains in structure-property relationship for the design of new polymers to be used in high efficient solar cells.     

一种高效简易的聚(4-乙烯基三溴化吡啶)催化乙醇合成乙酸盐的方法(英文)

Poly(4-vinylpyridinium tribromide) is an efficient catalyst for the conversion of various alcohols to their corresponding acetate derivatives with acetic anhydride.This method has some advantages such as mild reaction conditions,good to excellent yields,and ease of work-up.     

Cryoactivated proton-involved redox reactions enable stable-cycling fiber cooper metal batteries operating at -50 °C

Fiber-shaped batteries that feature outstanding flexibility, light weight, and wovenability are extremely attractive for powering smart wearable electronic textiles, which further stimulates their demand in extreme environments. However, there are rare reports on ultralow-temperature fiber batteries to date.This is mainly attributed to the poor conductivity of electrodes and freezing of electrolytes that restrain their satisfactory flexible operation in cold environments. Herein, we propose a fi...     

SIGNIFICANCE OF AUTHIGENIC MICROSPHEROID PYRITE BY SCANNING ELECTRON MICROSCOPE

This article discusses in detail the authigenic microspheroid pyrites in sediments by the scanning electron microscope, especially their basic types, surface structure and the surface changes of the single crystals in the kerogen of source rocks as well as their relation to the types of kerogen.     

Simultaneous Determination of Magnolol and Honokiol rby Synchronous Fluorescence Spectroscopy

A simple sensitive and quick assay for simultaneously determining magnolol （MOL） and honokiol （HOL） has been described based on their natural fluorescence. This method is based on the fact that synchronous fluorometry could resolve the overlapping of fluorescence spectra, which was aroused by their similar molecular structures. In this work, the synchronous spectrum, maintaining a constant difference of Aλ =10 nm between the emission and excitation wavelengths, has been selected for the determination of HOL and MOL. Under the optimum conditions, the fluorescence intensity is proportional to the concentration of MOL and HOL in solution over the range 0.075-0.7 μg/mL and 0.05-0.9 μg/mL with the detection limit of 0.029 μg/mL and 0.019 μg/mL, respectively. The method was applied to the simultaneous determination of MOL and HOL in pharmaceutical dosage with satisfactory results.     

Azide-alkyne click polymerization: An update

The great achievements of click chemistry have encouraged polymer scientists to use this reaction in their field.This review assembles an update of the advances of using azide-alkyne click polymerizati...