Simultaneously enhancing the thermal stability and electrochemical performance of solid polymer electrolytes by incorporating rod-like Zn2(OH)BO3 particles

Solid polymer electrolytes provide high safety and good electrochemical stability in solid-state lithium batteries (SSLBs) compared with conventional liquid electrolytes. In this work, a novel solid polymer composite electrolyte based on poly (ethylene oxide) (PEO) filled with rod-like Zn₂(OH)BO₃ particles was prepared by a grinding process followed with a heating treatment process and a cold pressing process. The effect of the incorporation amount of rod-like Zn₂(OH)BO₃ particles on the ionic conductivity was investigated systemically. It is found that 10 mol% of rod-like Zn₂(OH)BO₃ particles addition resulted in a highest ionic conductivity of 2.78 × 10⁻⁵ at 30 °C and the improved ionic conductivity was considered to be caused by the reducing of PEO crystallinity and the increasing of Li ion migrating pathway on the interface between the Zn₂(OH)BO₃ and PEO. In addition, the optimum composite electrolyte exhibited a high electrochemical stability window of 4.51 V (vs. Li/Li⁺), good lithium stability and excellent thermal stability.     

Mechanical properties of graphene films enhanced by homo-telechelic functionalized polymer fillers via π–π stacking interactions

Most researches on graphene/polymer composites are focusing on improving the mechanical and electrical properties of polymers at low graphene content instead of paying attention to constructing graphene’s macroscopic structures. In current study the homo-telechelic functionalized polyethylene glycols (FPEGs) were tailored with π-orbital-rich groups (namely phenyl, pyrene and di-pyrene) via esterification reactions, which enhanced the interaction between polyethylene glycol (PEG) molecules and chemical reduced graphene oxide (RGO) sheets. The π–π stacking interactions between graphene sheets and π-orbital-rich groups endowed the composite films with enhanced tensile strength and tunable electrical conductivity. The formation of graphene network structure mediated by the FPEGs fillers via π–π stacking non-covalent interactions should account for the experimental results. The experimental investigations were also complemented with theoretical calculation using a density functional theory. Atomic force microscope (AFM), scanning electron microscope (SEM), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), UV–vis and fluorescence spectroscopy were used to monitor the step-wise preparation of graphene composite films.     

Self-assembly of flower-like polyaniline–polyvinyl alcohol multidimensional architectures from 2D petals

Flower-like polyaniline–polyvinyl alcohol (PANI/PVA) multidimensional architectures assembled from 2D petals were successfully synthesized in the dilute solution of PVA by the oxidation polymerization. PANI/PVA flowers have a diameter of about 2.5 μm and consist of many interlaced sheet petals. Chemical structure and composition of polymerized PANI/PVA were characterized by Fourier transform infrared (FTIR) spectroscopy, Ultraviolet and visible spectroscopy (UV–vis), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In order to research the formation mechanism of the 3D flower-like PANI/PVA, their growth process was followed by measuring the morphological evolutions of products with the different polymerization times. The results showed that the flower-like PANI/PVA originated from sheet petals, which then self-assembled into flower-like microstructures. In addition, the effect of PVA concentration on the morphology of the 3D flower-like PANI/PVA was also investigated.     

Preparation of layered nickel aluminium double hydroxide from waste solution of nickel

The separation of nickel has been carried out from a waste solution containing 3.18 g/L Ni with other impurities such as Fe, Zn, Cu and As. Iron was removed by precipitation and Cu and Zn were removed by solvent extraction using LIX 622N and NaTOPS-99, respectively. After removal of all these impurities nickel was extracted by 1.5 M NaTOPS-99 in two counter-current stages at A:O ratio of 3:1 and the loaded organic was stripped with 30 g/L H₂SO₄ at phase ratio of unity. The strip solution of nickel was treated with Al₂(NO)₃ · 9H₂O for co-precipitation by increasing the pH of solution with 1 M NaOH up to 10. The Ni–Al layered double hydroxide was confirmed through XRD characterization.     

Cyanide and removal options from effluents in gold mining and metallurgical processes

Cyanide has been widely used as an essential raw material in several industries including textile, plastics, paints, photography, electroplating, agriculture, food, medicine and mining/metallurgy. Because of its high affinity for gold and silver, cyanide is able to selectively leach these metals from ores. Cyanide and cyanide compounds in wastewater streams are regulated. Residues and wastewater streams containing cyanide compounds have to be treated to reduce the concentration of total cyanide and free cyanide below the regulated limits.Natural degradation reactions can render cyanide non-toxic, resulting in carbon dioxide and nitrogen compounds. These natural reactions have been utilised by the mining industry as the most common means of attenuating cyanide. However, the rate of natural degradation is largely dependent on environmental conditions and may not produce an effluent of desirable quality in all cases year round. Technologies that include chemical, biological, electrochemical and photochemical methods have been developed to remove cyanide and cyanide compounds to below the regulated limits in wastewaters. This paper discusses commercially available and emerging methods for removing cyanide from waste streams, particularly from tailings and tailings reclaim waters that are generated in the gold mining processes.     

Process intensification applied to an aqueous LiBr rotating absorption chiller with dry heat rejection

This paper describes the development and operation of a rotating double effect absorption heat pump, which uses an aqueous lithium bromide solution as the absorbent and dry heat rejection. The design principles are outlined including the operation of the major components and the ways in which the integration of the processes has been achieved. The operation of the fluid management system is described. Experimental performance data are presented from laboratory testing for the machine operating as a chiller.     

Small wind turbine for built up areas

A UK-based inventor is offering for license a small wind turbine design that uses proven technology based on high lift aircraft wing designs and commercially proven small turbine generators. The technology called Combined Augmentation Turbine Technology or CATT comprises a conventional horizontal axis propeller rotating within a short aerodynamic duct. The key to the technology is a unique method of controlling airflow through the duct, such that its performance is guaranteed in any wind regime. This results in a modern version of a ducted turbine suitable for use in built up areas where wind quality and speed is variable and generally lower (typically 3 to 7 m/s) than on wind farm sites (8 to 10m/s). The CATT duct configuration is designed to ‘process’ the veering and slightly turbulent winds into a smoother air flow which generates up to 70% more torque and power generating capability than from the propeller alone. The speed of the propeller is controlled by turning the duct horizontally, such that noise, wear and safety issues are minimized. In comparison to non-ducted turbines, the inventor claims that CATT operates in moderate wind speeds, is less sensitive to wind velocity/quality, runs quieter and requires lower cost blades.This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news.     

Effects of thin film processing on pentacene/C60 bilayer solar cell performance

Solar cells based on pentacene/C₆₀ bilayer heterojunctions have been fabricated with a structure of ITO/poly(styrenesulfonate) (PEDOT:PSS)/pentacene (40 nm)/fullerene (C₆₀)(40 nm)/2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) (10 nm)/Al. The effect of pentacene crystalline domain size on performance was investigated by controlling the pentacene deposition rate. The devices show improved light-to-electricity conversion efficiencies from 0.49% to 1.12% under an AM 1.5 solar simulator (100 mW/cm²), when the pentacene evaporation rate is in a range of 5 Å/s–0.5 Å/s. Atomic force microscopy (AFM) measurements show that the pentacene films deposited by a slow evaporation rate have larger crystalline domains and a fewer amorphous domains, compared to films obtained by faster evaporation rates. Upon thermal annealing at 200 °C for 1 min, there is merging of pentacene crystalline domains. These changes in film morphology impact the charge separation at the donor/acceptor interface and the hole and electron mobilities, and hence, directly affect the device performance.     

Application of membrane separation processes in petrochemical industry: a review

In this paper a general review on different membrane processes and membrane reactors was done. As the main aim of this paper is to review the application of membrane processes in petrochemical industry, processes such as olefin/paraffin separation, light solvent separation, solvent dewaxing, phenol and aromatic recovery, dehydrogenation, oxidative coupling of methane and steam reforming of methane were discussed in detail. Besides, separation using polymer-inorganic nano composite membranes and wastewater treatment using membrane bio-reactors were reviewed.     

Ag/AgCl微电极束的制作及其原位检测焊缝局部腐蚀的效果

金属焊接件焊缝处易优先发生腐蚀,单个微电极难以测量焊接件同一时刻、不同位置的局部腐蚀行为。自制了Ag/AgCl微电极束,用其测试了X80钢焊接件在天然海水和模拟的咸淡水(0.1 mol/L NaCl溶液)中以及X65-316L焊接件在模拟的酸性海洋大气环境(0.1 mol/L,pH=2的NaCl溶液)中的电位分布,预测了焊材的局部腐蚀行为。结果表明:制作的Ag/AgCl微电极束性能稳定,用其测定X80焊接件和X65-316L焊接件在不同环境中的电位分布,可准确推测腐蚀发生的位置。