Fabrication and characterization of a high performance polyimide ultrafiltration membrane for dye removal.

Membrane separation technology is one of the cost effective and most efficient technologies for treatment of wastewater from textile industry. However, development of membranes with better performance and thermal stability is still a highly challenging task. In this study, successful preparation of a novel thermally stable polyimide (PI) polymer was demonstrated using 2,4,6-trimethyl-1,3-phenylenediamine, 4,4'-diaminodiphenylmethane and 1,2,4,5-benzenetetracarboxylic dianhydride components.

Highly Efficient Purification of Multicomponent Wastewater by Electrospinning Kidney-Bean-Skin-like Porous H-PPAN/rGO--PAO@Ag/Ag Composite Nanofibrous Membranes.

Due to the complexity of harmful wastewater components, environmental and multifunctional materials are required for sewage purification. In this paper, a novel kidney-bean-skin-like hydrophilic porous polyacrylonitrile/reduced graphene oxide--poly(amidoxime)-loaded Ag (H-PPAN/rGO--PAO@Ag/Ag) composite nanofiber membrane was fabricated by combining electrospinning and hydrolysis methods. The spinning solution was pumped at a rate of 0.

S Doped ZnO Nanowires@PAN Nanofibrous Membranes for Photocatalytic Degradation of Dye.

Background: Wastewater involving a lot of contaminants like organic dyes from the textile finishing industry causes a greater adverse impact on human beings. There are many patents on nanofibers involved metallic oxides, this paper studies photocatalytic degradation of free-pollution Zinc Oxide (ZnO) nanomaterials on dye decontamination.

Objective: Polyacrylonitrile (PAN) nanofibrous membranes loaded with Zinc Oxide (ZnO) nanowires were fabricated and evaluated for photocatalytic degradation.

Hierarchically Assembled Graphene Oxide Composite Membrane with Self-Healing and High-Efficiency Water Purification Performance.

Graphene oxide (GO) with a two-dimensional lamellar structure and single-atom thickness has exhibited advantages in water purification by stacking to a continuous membrane. However, a proper method to further increase the separation property of the GO membrane is still urgently needed. Besides, damage to the membrane during the full-scale application processes and the resulted consequential loss are prevalent problems need to be solved.

Recent Progress in Carbon-Based Buffer Layers for Polymer Solar Cells.

Carbon-based materials are promising candidates as charge transport layers in various optoelectronic devices and have been applied to enhance the performance and stability of such devices. In this paper, we provide an overview of the most contemporary strategies that use carbon-based materials including graphene, graphene oxide, carbon nanotubes, carbon quantum dots, and graphitic carbon nitride as buffer layers in polymer solar cells (PSCs). The crucial parameters that regulate the performance of carbon-based buffer layers are highlighted and discussed in detail.

Catalytic degradation of TCE by a PVDF membrane with Pd-coated nanoscale zero-valent iron reductant.

Trichloroethylene (TCE) has serious threat to ecosystem. Fe-Pd nanoparticles (NPs) are good materials for catalytic degradation of TCE but still face severe challenges including easy fouling, agglomeration, deactivation and difficult separation and reuse etc. To overcome these drawbacks, we have constructed a novel structured PVDF/Fe-Pd NPs composite membrane with nanosized surface pores to execute the TCE degradation.

Cluster-Nuclei Coassembled into Two-Dimensional Hybrid CuO-PMA Sub-1 nm Nanosheets.

In the sub-1 nm scale region, nanomaterials have shown some novel and interesting chemical and physical properties, such as flexibility, polymer-like rheology, etc. However, how to limit the size of hybrid nanomaterials into sub-1 nm scale is still a great challenge. Herein, by incorporating phosphomolybdic acid (PMA) clusters into inorganic materials (CuO) during the nucleation step, we first synthesized the two-dimensional (2D) hybrid CuO-PMA sub-1 nm nanosheets (SNSs).

4-aminoantipyrine modified carbon dots and their analytical applications through response surface methodology.

A sensitive and selective nanoprobe for detection of hypochlorite (OCl) based on 4-aminoantipyrine (AAP) modified carbon dots (CDs-AAP) has been prepared. The CDs-AAP exhibit an emission peak at 484 nm when the excitation wavelength is 370 nm, accompanying 36 nm red shift compare with the pristine CDs. The addition of OCl lead to the AAP on the surface of CDs experience a process of hydrazide hydrolysis and double bond addition, causing the singlet and triplet electrons of the excited state more closer in energy (ie, the energy difference between the two is reduced), eventually quenching the fluorescence of CDs due to heavy atomic effects.

Determination of ultra trace amounts of metronidazole by 3-phenyl-N-[4-(10,15,20-triphenyl-porphyrin-5-yl)-phenyl]- acrylamide as the fluorescence spectral probe in CTAB microemulsion.

In this work, 3-Phenyl-N-[4-(10,15,20-triphenyl-porphyrin-5-yl)-phenyl]- acrylamide (TPPCA) was synthesized for the determination of metronidazole (MTZ). It was found that the type of fluorescence quenching was static quenching determined by Stern-Volmer plot and UV absorption spectroscopy, and thermodynamic related parameters were also obtained. Furthermore, the corresponding measurement conditions: the acidity of the system, the type of surfactant, the concentration of TPPCA and the sequence of reagent addition were optimized.

Fabrication of centrifugally spun prepared poly(lactic acid)/gelatin/ciprofloxacin nanofibers for antimicrobial wound dressing.

Centrifugal spinning is a novel technology for producing ultrafine fibers in high yield with diameters ranging from micro to nanometers. The obtained fibers have potential applications in the field of tissue engineering, wound dressing, and biomedicine In this paper, a system of poly(lactic acid)/gelatin (PLA/GE) nanofibers loaded with ciprofloxacin (CPF) drug for wound dressings were successfully prepared by centrifugal spinning. The nanofibers were characterized by scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR).

Study on Preparation and Separation and Adsorption Performance of Knitted Tube Composite β-Cyclodextrin/Chitosan Porous Membrane.

In order to obtain membranes with both organic separation and adsorption functions, knitted tube composite β-cyclodextrin/chitosan (β-CD/CS) porous membranes were prepared by the non-solvent induced phase separation (NIPS) method using CS and β-CD as a membrane-forming matrix, glutaraldehyde as crosslinking agent to improve water stability, and knitted tube as reinforcement to enhance the mechanical properties. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), contact angle, water flux, bovine serum albumin (BSA) rejection and tensile test were carried out. The FTIR demonstrated that the β-CD and CS had been successfully crosslinked.

N-Propyl-N-Methylpyrrolidinium Difluoro(oxalato)borate as a Novel Electrolyte for High-Voltage Supercapacitor.

Development of high voltage electrolyte is one of the effective ways to improve the performance of supercapacitor. The new ionic liquid N-propyl-N-methylpyrrolidinium difluoro(oxalato)borate (PyDFOB) was designed and mixed with propylene carbonate (PC) as electrolyte for supercapacitor. The operating voltage of the new electrolyte system has been proven to be up to 3.

Effect of volatile solvent and evaporation time on formation and performance of PVC/PVC--PEGMA blended membranes.

In order to further improve the performances of fabricated PVC/PVC--poly(ethylene glycol) methyl ether methacrylate (PVC/PVC--PEGMA) blended membranes, we investigated the inner connections between affecting parameters during preparation and membrane performances. Two parameters including the composition of casting solutions and the solvent evaporation time were selected. In this study, PVC/PVC--PEGMA blended membranes were prepared by non-solvent induced phase separation (NIPS) using 1-methyl-2-pyrrolidinone (NMP) and tetrahydrofuran (THF) as mixing solvents.

Fabrication of a Novel Nanofiltration Membrane with Enhanced Performance via Interfacial Polymerization through the Incorporation of a New Zwitterionic Diamine Monomer.

It is known that the polyamide (PA) barrier layer's inherent microstructure and surface physicochemical properties of thin film composite nanofiltration membrane are crucial for its separation performance. Herein, we designed and synthesized a new zwitterionic aromatic diamine monomer 3-(4-(2-((4-aminophenyl)amino)ethyl)morpholino-4-ium)propane-1-sulfonate (PPD-MEPS) through a three steps reaction, and this hydrophilic molecule was incorporated into the active layer to tailor the poly(piperazine-amide)-based nanofiltration membranes with significantly improved water permeability and antifouling properties. As a -phenylenediamine (PPD) derivative, PPD-MEPS possesses two active amine units, which can react with trimesoyl chloride in the organic phase during the interfacial polymerization reaction process.

Novel fluorescein- and pyridine-conjugated schiff base probes for the recyclable real-time determination of Ce and F.

The effect of aminopyridines substituted at different positions on the fluorescence properties deserves to be studied. Since 2-aminopyridyl-based probes have been reported, the effects of 3-aminopyridine and 4-aminopyridine on the performance of fluorescein probes were discussed in here. Two Schiff base fluorescein probes FN-1, FN-2 were designed and synthesized.

High Performance of PIM-1/ZIF-8 Composite Membranes for O/N Separation.

This work reports the preparation, characterization, and O/N separation properties of composite membranes based on the polymer of intrinsic microporosity (PIM-1) and the zeolitic imidazolate framework (ZIF-8). Especially, the composite membranes were prepared by growing ZIF-8 nanoparticles on one side of the PIM-1 membrane in methanol. Fourier transform infrared spectroscopy and thermo-gravimetric analysis indicated that there is no strong chemical interaction between ZIF-8 nanoparticles and PIM-1 chains.

Multilayer Nanofiber Composite Separator for Lithium-Ion Batteries with High Safety.

An original Von Koch curve-shaped tipped electrospinneret was used to prepare a polyimide (PI)-based nanofiber membrane. A multilayer AlO@polyimide/polyethylene/AlO@polyimide (APEAP) composite membrane was tactfully designed with an AlO@ polyimide (AP) membrane as outer shell, imparting high temperature to the thermal run-away separator performance and a core polyethylene (PE) layer imparts the separator with a thermal shut-down property at low temperature (123 °C). An AP electrospun nanofiber was obtained by doping AlO nanoparticles in PI solution.

Musical training sharpens behavioral tuning more saliently than peripheral tuning.

Musical training appears to enhance performance at both peripheral and central auditory sites. We compared behavioral and peripheral frequency tuning in normal-hearing musicians and nonmusicians, whose native language is Mandarin. The results indicate that, at higher probe frequencies, musical training sharpens behavioral tuning more saliently than peripheral tuning.

Effects of uninterrupted sinusoidal LF-EMF stimulation on LTP induced by different combinations of TBS/HFS at the Schaffer collateral-CA1 of synapses.

Long-term potentiation (LTP) is an important aspect of synaptic plasticity and is one of the main mechanisms involved in memory. Low-frequency electromagnetic fields (LF-EMFs) such as transcranial magnetic stimulation are emerging neuromodulation tools for the regulation of LTP. However, whether LF-EMFs have different effects on different types of LTP has not yet been verified.

Free-Standing CoO-POM Janus-like Ultrathin Nanosheets.

A single-step solution-based strategy is used to obtain 2D Janus-like free-standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D-to-1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM-CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene.

Location of Tensile Damage Source of Carbon Fiber Braided Composites Based on Two-Step Method.

Acoustic emission (AE) source localization is one of the important purposes of nondestructive testing. The localization accuracy reflects the degree of coincidence between the identified location and the actual damage location. However, the anisotropy of carbon fiber three-dimensional braided composites will have a great impact on the accuracy of AE source location.

Characteristic of Stimulus Frequency Otoacoustic Emissions: Detection Rate, Musical Training Influence, and Gain Function.

Stimulus frequency otoacoustic emission (SFOAE) is an active acoustic signal emitted by the inner ear providing salient information about cochlear function and dysfunction. To provide a basis for laboratory investigation and clinical use, we investigated the characteristics of SFOAEs, including detection rate, musical training influence, and gain function. Sixty-five normal hearing subjects (15 musicians and 50 non-musicians, aged 16-45 years) were tested and analyzed at the probe level of 30 and 50 dB sound pressure levels (SPL) in the center frequency of 1 and 4 kHz in the study.

Effects of carbon nanotubes on growth of wheat seedlings and Cd uptake.

Carbon nanotubes (CNTs) have been widely used in many scientific fields including plant sciences due to their unique physical and chemical properties. However, little is known about the toxic effects of CNTs combined with cadmium (Cd) on wheat. The aim of this study was to investigate the effects of single-walled carbon nanotubes (SW) and multi-walled carbon nanotubes (MW) on the phytotoxicity of Cd in wheat.