Fibers and 3D mesh scaffolds from biodegradable starch-based blends: production and characterization

The aim of this work is the production of fibers from biodegradable polymers to obtain 3D scaffolds for tissue engineering of hard tissues. The scaffolds required for this highly demanding application need to have, as well as the biological and mechanical characteristics, a high degree of porosity with suitable dimensions for cell seeding and proliferation. Furthermore, the open cell porosity should have adequate interconnectivity for a continuous flow of nutrients and outflow of cell metabolic residues as well as to allow cell growth into confluent layers. Blends of corn starch, a natural biodegradable polymer, with other synthetic polymers (poly(ethylene vinyl alcohol), poly(epsilon-caprolactone), poly(lactic acid)) were selected for this work because of their good balance of properties, namely biocompatibility, processability and mechanical properties. Melt spinning was used to produce fibers from all the blends and 3D meshes from one of the starch-poly(lactic acid) blends. The experimental characterization included the evaluation of the tensile mechanical properties and thermal properties of the fibers and the compression stiffness, porosity and degradation behavior of the 3D meshes. Light microscopy picture of 3D meshes.     

Facile cyclic ammonium salt with the smallest size for high performance electric double layer capacitors

A novel cyclic ammonium salt, N,N-dimethylpyrrolidinium tetrafluoroborate (P₁₁-BF₄), was successfully synthesized for the first time. The smallest cyclic structure of P₁₁-BF₄ induced high solubility and conductivity in PC, which can easier enter the micropores of activated carbon and occupy more surface area during charge/discharge process.     

一种用于空气中二氧化碳现场测定的新方法

一种用于空气中二氧化碳现场测定的新方法于爱民，杨广德，王锐，金钦汉（吉林大学化学系，长春１３００２３）关键词微波诱导等离子体，离子化检测器，气相色谱仪，二氧化碳二氧化碳在植物生长代谢及其生态平衡过程中起着重要作用，现场测定二氧化碳是目前农业、环境科学...     

Synthesis and Crystal Structure of （Et4N）2[Pd2（mp）2（mpH）2]

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆ（Ｅｔ_４Ｎ）_２［Ｐｄ_２（ｍｐ）_２（ｍｐＨ）_２］ＳｈｉＪｉ－Ｃｈｅｎｇ；ＨｕａｎｇＸｉａｏ－Ｙｉｎｇ；ＷｅｎＴｉｎｇ－Ｂｉｎ；ＤｅｎｇＹｕ－Ｈｅｎｇ；ＣｈｅｎｇＣｈａｎｇ－Ｎｅｎｇ；Ｌｉ?..     

A vacuum ultraviolet photoionization mass spectrometric study of acetone

The photoionization and dissociative photoionization of acetone have been studied at the photon energy range of 8-20 eV. Photoionization efficiency spectra for ions CH3COCH3+, CH3+, C2H3+, C3H3+, C3H5+, CH(2-)CO+, CH3CO+, C3H4O+, and CH3COCH2+ have been measured. In addition, the energetics of the dissociative photoionization has been examined by ab initio Gaussian-3 (G3) calculations. The computational results are useful in establishing the dissociation channels near the ionization thresholds. With the help of G3 results, the dissociation channels for the formation of the fragment ions CH3CO+, CH2CO+, CH3+, C3H3+, and CH3COCH2+ have been established. The G3 results are in fair to excellent agreement with the experimental data.     

氮硫杂冠醚及其衍生物的合成

以噻吩、水杨醛、二胺、溴乙酸、烯丙基氯和丙烯腈为原料合成了 4,5 :14 ,15 二苯 3 ,16 二氧 2 1 硫 7,12 二氮双环[16.2 .1]二十一环 1( 2 0 ) ,18 二烯 (简称氮硫杂冠醚 )及其 5种衍生物 ,经元素分析 ,IR ,1 HNMR和MS谱表征了这些化合物的结构 .     

水热法合成Ce0.67Zr0.33O0.2固溶体研究

采用两种不同前驱体通过水热法合成了Ce0.67Zr0.33O0.2固溶体,并通过XRD,BET,TPR等手段考察了样品的相结构,比表面及还原特性.结果表明,在180℃,12 h的水热条件下,以共沉淀产物为前驱体所制得的Ce0.67Zr0.33O0.2固溶体比表面积较高,但存在一定程度的相分离;以凝胶产物为前驱体制得的Ce0.67Zr0.33O0.2固溶体结构更完整,具有良好的还原特性及热稳定性.     

Photopolymerization induced by a benzophenone derivative photoinitiator

A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP （HTCTH）, was synthesized based on 4-hydroxy benzophenone （HBP）, toluene-2,4-diisocyanate （TDI） and hydroquinone （HQ）. HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone （BP）. It showed that both rate of polymerization （Rp） and final conversion （P） increased with increase of amine and HTCTH concentration in photopolymerization.     

An Efficient Synthesis of Pyrazolo[3,4‐b]Pyridine Derivatives in Aqueous Media

A series of pyrazolo[3,4‐b]pyridines was synthesized by the reaction of 5‐aminopyrazole with benzylidenemalononitrile in aqueous media. The structures were characterized by IR, ¹H NMR, and elemental analysis and were further confirmed by X‐ray diffraction analysis.     

1－芳氧乙酰氧基－1－（1H－1，2，4－三唑－1－基）－3，3－二甲基－2－丁酮衍生物的研究

以三乙胺为缚酸剂，用芳氧乙酸同ω－溴代－ω－（１Ｈ－１，２，４－三唑－１－基）频哪酮反应，合成了一系列三唑类新化合物，探讨了化合物的合成方法。通过ＩＲ￣１ＨＮＭＲ、ＭＳ分析及元素分析确定了化合物的结构，生物活性测定结果表明，部分化合物具有良好的除草活性，同时表现出一定程度的植物生长调节活性及杀菌活性．