Double-emulsion templated macroporous cellulose microspheres as a high-performance chromatographic media for protein separation

Cellulose - Cellulose microspheres are commonly chromatographic media yet seriously limited in biomacromolecules separation and purification due to the slow mass transfer kinetics resulting from...     

High-strength and low-swelling chitosan/cellulose microspheres as a high-efficiency adsorbent for dye removal

Cellulose - Dye contamination of water supplies has a serious threat to human health, prompting the development of highly effective and eco-friendly adsorbents. In this work, polyelectrolyte...     

Synthesis,Adsorptive, and Photocatalytic Properties of Carbon Nanotubes/TiO<Subscript>2</Subscript> Nanocomposite Photocatalysts

The carbon nanotubes/TiO₂ (CNTs/TiO₂) composite photocatalysts composed of TiO₂ nanoparticles and multiwalled carbon nanotubes (CNTs) were prepared by a facile hydrothermal method. The photocatalysts were characterized by a range of analytical techniques including X-ray powder diffraction, field emission scanning electron microscope, thermal gravimetric analysis and UV–Vis optical absorption spectra, etc. The amount of TiO₂ nanoparticles growing on CNTs could be tuned by adjusting the dosage of precursor in the reaction solution. Both the adsorptivity and photocatalytic activities of pure CNTs, pure TiO₂, and the CNTs/TiO₂ nanocomposites were tested by the removal of methylene blue from water in dark and under a simulated sunlight, respectively. By comparison, the improved photocatalytic activity of the CNTs/TiO₂ nanocomposite is mainly due to that the CNTs can disperse the active component of TiO₂ nanoparticles, provide a larger the specific surface area, as well as act as an electron sink to accelerate the separation of the photogenerated charges.     

Mössbauer spectroscopic study on nanocrystalline LaFeO3 materials

Perovskite-type nanocrystalline materials LaFeO₃ with different crystal size were synthesized. These samples with different compacted pressure were investigated by Mössbauer spectroscopy at room temperature. The results showed that the LaFeO₃ crystal in size of 70nm possessed an antiferromagnetic structure, that of 12nm was the superposition of the weaker antiferromagnetic structure and the stronger superparamagnetic structure. The rate of interface atoms to crystal atoms and the hyperfine field in nanocrystals varied with the compacted pressure.     

Citronellol-Based Long-Lasting Antibacterial Cotton Fabrics without Bacterial Resistance

Antibacterial cotton helps prevent the growth and spread of harmful microorganisms, reduces the risk of infection, and has a prolonged service life by reducing bacterial degradation. However, most antibacterial agents used are toxic to humans and the environment. Citronellol-poly(N,N-dimethyl ethyl methacrylate) (CD), a highly effective antibacterial polymer, is synthesized from natural herbal essential oils (EOs). CD exhibited efficient, rapid bactericidal activity against Gram-positive, Gram-negative, and drug-resistant bacteria. Citronellol's environmental benignity makes CDs less hemolytic. Notably, negligible drug resistance developed after 15 bacterial subcultures. The CD-treated cotton fabric displayed better antibacterial performance than AAA-grade antibacterial fabric, even after repeated washing. This study extends the practical application of EOs to antibacterial surfaces and fabrics, which is promising for use in personal care products and medical settings.     

Preparation and Characterization of Monodispersed Co2O3 Ultrafine Particle Sol

The present, paper contains a new composite material Co_2O_3UFP sol prepared by using W/O microemulsion method, and its size distribution, interracial and optical nonlincar properties are discussed. The method for the preparation of UFP sol is as follows: at first, CoCl_2 and DBS so-     

One-step formation of w/o/w multiple emulsions stabilized by single amphiphilic block copolymers

Multiple emulsions are complex polydispersed systems in which both oil-in-water (O/W) and water-in-oil (W/O) emulsion exists simultaneously. They are often prepared accroding to a two-step process and commonly stabilized using a combination of hydrophilic and hydrophobic surfactants. Recently, some reports have shown that multiple emulsions can also be produced through one-step method with simultaneous occurrence of catastrophic and transitional phase inversions. However, these reported multiple emulsions need surfactant blends and are usually described as transitory or temporary systems. Herein, we report a one-step phase inversion process to produce water-in-oil-in-water (W/O/W) multiple emulsions stabilized solely by a synthetic diblock copolymer. Unlike the use of small molecule surfactant combinations, block copolymer stabilized multiple emulsions are remarkably stable and show the ability to separately encapsulate both polar and nonpolar cargos. The importance of the conformation of the copolymer surfactant at the interfaces with regards to the stability of the multiple emulsions using the one-step method is discussed.     

Design of super-tough and antibacterial PPR/nano-ZnO composites based on the excellent dispersion of ZnO particles

Herein, polyvinyl pyrrolidone (PVP) dispersants are used to disperse and isolate zinc oxide (ZnO) particles. A high-pressure spray device is used to dry the dispersed nano-fillers quickly to achieve the structure of PVP chains wrapping and isolating ZnO particles. Scanning electron microscopy shows that most of the size of the agglomerated ZnO nanoparticles in polypropylene random (PPR, obtained by random copolymerization of propylene and ethylene) is maintained below 100 nm, and only a small amount of large agglomerates with a particle size less than 400 nm. An excellent dispersion of nano-ZnO fillers prepared by this method can greatly improve the toughness of PPR and endow it with good antibacterial properties. When the content of the ZnO nanoparticles is 3 wt%, the notched impact strength of PVZ3 increases to 48.85 kJ m⁻² (unbroken), which is 3.6 times than that of pure PPR. In addition, 3 phr ZnO nanoparticles give PPR excellent antibacterial properties, with an antibacterial rate of 99.9% (Escherichia coli and Staphylococcus aureus). The value of antibacterial activity (E. coli) of PVZ3 reached more than 6.0, which is nearly three times that of PZ.     

单柱离子色谱法同时测定碱金属、铵离子和胺类

用草酸为淋洗液的单柱离子色谱法同时测定了碱金属、铵离子和胺类。淋洗液的最佳浓度为４．０ｍｍｏｌ／Ｌ,在此条件下测得了碱金属、铵离子和胺类的检出限、相对标准偏差和工作曲线方程,应用于自来水、井水、汽水和雪样分析,结果良好。     

Surface Photovoltage Studies of Moisture Sensitive Characteristic of Copper Tetrasulfonato-Phthalocyanine

The surface photovoltaic characteristic of copper tetrasulfonato- phthalocyanine (CuTsPc) in water vapor was studied by surface photovoltage spectroscopy (SPS). It was found that the adsorption of water vapor caused some marvelous changes of the photovoltaic response, that is, the SPS signal diminished rapidly and even reversed; the bands were widened and displayed a bathochromic shift. The dependence of surface photovoltage on the vapor pressure indicates that the reversed signal reaches to a maximum when the vapor pressure is 4.7×102 Pa. The time response velocity, reversibility, selectivity and reproducibili-ty were examined as well. All results obtained show that CuTsPc is of great significance in the manufacture of moisture sensitive devices. In addition, the mechanism of moisture sensitivity is discussed.