Using atmospheric pressure plasma for enhancing the deposition of printing paste on cotton fabric for digital ink-jet printing

Atmospheric pressure plasma (APP) treatment was applied as a pretreatment process to enhance the deposition of printing paste in order to improve the final colour properties of digital ink-jet printed cotton fabrics. Three printing pastes containing natural polymers, i.e. (1) sodium alginate, (2) chitosan and (3) sodium alginate-chitosan mixture, were prepared separately. After APP treatment, cotton fabric was padded with different printing pastes prior to digital ink-jet printing. Experimental results showed that APP pretreatment could increase the colour yield of the digital ink-jet printed cotton fabric significantly even after washing. In addition, other properties such as colour fastness to crocking, colour fastness to laundering, outline sharpness and anti-bacterial properties were also improved when compared with those of the control cotton fabric printed without APP pretreatment. However, the influence of printing paste on the colour properties of the digital ink-jet printed cotton fabrics depended very much on the composition of the printing paste. The scanning electron microscope images evidenced that the APP treatment could enhance the deposition of printing paste on the cotton fabric surface as proved qualitatively by both the contact angle and wetting time measurement as well as quantitatively by both the X-ray photoelectron spectroscopy and carboxyl group/nitrogen content analysis.     

环境敏感水凝胶的研究进展

综述了环境敏感水凝胶在制备、功能性及其应用方面的研究进展 ,尤其是温敏水凝胶、pH敏感水凝胶和盐敏水凝胶的研究状况 ,也对光敏和生物分子敏感水凝胶进行了简单评述     

Effects of shell composition,dosage and alkali type on the morphology of polymer hollow microspheres

Polymer hollow microspheres were prepared by performing alkali treatment on the multilayer core/shell polymer latex particles containing carboxyl groups. Effects of the shell composition and dosage as well as alkali type on the morphology of the microspheres were investigated. Results showed that in comparison with acrylonitrile(AN) and methacrylic acid(MAA), using butyl acrylate(BA) as the shell co-monomer decreased the glass transition temperature(T_g) of shell effectively and was beneficial to the formation of uniform and big hollow structure. Along with the increase of the shell dosage, the alkali-treated microspheres sequentially presented porous and hollow morphology, and the size of microspheres increased, while the hollow diameter increased first and then decreased, and the maximum hollow ratio reached 39.5%. Furthermore, the multilayer core/shell microspheres had better tolerance to NH_3·H_2O than to NaOH. When the molar ratio of alkali to methacrylic acid(MR_(alkali/acid)) for Na OH ranged from 1.15 to 1.30 or MRalkali/acid for NH_3·H_2O ranged from 1.30 to 2.00, the regular polymer hollow microspheres could be obtained.     

Synthetic Two-dimensional Organic Structures

Synthetic two-dimensional(2 D) polymers have totally different topology structures compared with traditional linear or branched polymers. The peculiar 2 D structures bring superior properties. Although, from linear to 2 D polymers, the study of these new materials is still in its infancy, they already show potential applications especially in optoelectronics, membranes, energy storage and catalysis, etc. In this review, we summarize the recent progress of the 2 D materials from three respects:(1) Chemistry—different types of polymerization reactions or supramolecular assembly to construct the 2 D networks were described;(2) Preparation methods—surface science, crystal engineering approaches and solution synthesis were introduced;(3) Functionalization and some early applications.     

Synergistic effects of CdS in sodium titanate based nanostructures for hydrogen evolution

Synergistic effect of CdS decorated sodium titanate nanostructures showed enhanced H₂ production abilities. The confinement effect and synergistic effect of decorated CdS inside the sodium titanate nanotubes are investigated.     

Synthesis of the Chiral Pair of a Novel Thromboxane Antagonist, 3‐[2‐(3‐Benzenesulfonylamino‐7‐oxabicyclo[2.2.1]hept‐2‐yl‐methyl)phenyl] Propionic Acid

Preparation of the enantiomeric pair of 3‐[2‐(3‐benzenesulfonylamino‐7‐oxabicyclo[2.2.1]hept‐2‐yl‐methyl)phenyl] propionic acid, a novel thromboxane antagonist is reported. They are synthesized from either enantiomers of known (1R,2R,3R,4S)‐3‐[2‐(3‐carboxy‐7‐oxabicyclo[2,2,1]hept‐2‐yl‐methyl)phenyl]‐propionic acid methyl ester via epimerization, modified Curtius' rearrangement and sulfonylamino formation. Other derivatives may be prepared similarly.     

Structure and coordination environment of the zinc complex with vanillin of double-stranded helix

The structure and coordination environment of unusually double-stranded helix of complex [Zn(C₈H₇O₃)₂(H₂O)₂] are studied experimentally and by the density functional theory (DFT) method. The Zn²⁺ ion coordinates six oxygen atoms of deprotonated vanillin and water molecules forming an octahedron. The intermolecular hydrogen bonds and π interactions of the vanillin fragments contributed to the formation of the double-stranded helical supramolecular structure in the crystal. Counterpoise geometric parameters of the calculation agree with the crystal structure determined by experiment. The stabilization energy between the donor and acceptor obtained from an analysis of natural bond orbitals of the indicated six ligand oxygen atoms act as electron donor to Zn²⁺ ion. The results of the density functional theory on the complex demonstrate that the different coordinated oxygen atoms, which have different chemical environment, distort the coordination octahedron. The text was submitted by the authors in English.     

Highly efficient cryogenically-cooled Yb:YAG laser

A MOPA laser system for high pulse energy and high average power has been developed by using a cryogenic Yb:YAG. In the regenerative amplifier with our original TRAM architecture, the high pulse energies of 6.5 and 1.5 mJ were obtained at the repetition rate of 200 Hz and 1 kHz, respectively. An optical efficiency was as high as η_o-o = 9.3% with an excellent beam quality of M ² < 1.1, which ensured that a cryogenic Yb:YAG TRAM had a high thermal strength. The following four pass power amplifier with a cryogenic Yb:YAG rod showed 140 mJ at 100 Hz. Both a high optical efficiency of η_o-o = 30% and a high slope efficiency of η_s = 44% showed that an efficient laser operation could be realized for a power amplification with both a high pulse energy and a high average power by using a cryogenic Yb:YAG.     

Biosafety evaluation and quantitative determination of poly(hexamethylene biguanide) (PHMB) coated on cellulosic fabrics by Kubelka–Munk equation

Cellulose - It is difficult to directly determine the quantity of cationic finishing agents on the surface of cellulosic fabrics. Herein, we report a direct and feasible method by...     

近红外发光Ag2S-CdS 核壳结构水溶性量子点的合成及光学性质

本文以谷胱甘肽(GSH)作为表面活性剂,采用两步法,先生成Ag2S核,再生长CdS,得到了高质量的Ag2S-CdS核壳结构水溶性量子点。我们用XRD,TEM,HRTEM和EDS研究了产物的结构,形貌和组分,用紫外可见吸收光谱和荧光发射光谱研究了所得量子点的光学性质,同时考察了反应时间,GSH的量,Ag和S源前驱物的含量对量子点光学性质的影响。实验结果表明量子点稳定性好,荧光寿命长,可在710~718 nm近红外区域发光。在核生长过程中,Ag和S源的含量同时影响量子点的发光位置和强度,而GSH量和壳层生长中S源的量几乎只影响近红外发光强度,发光位置保持不变。不同的量子点光学性质可能来源于量子点中组分及表面缺陷的分布。