微米级薄片木纤维高强度人造板制造工艺的试验研究

利用微米级长木纤维在实验室成功地压制了人造板,初步验证了微米级木纤维形成高强度纤维板(MFB)的细胞裂解理论。试验结果表明这种板材外观呈现木本色,在某些物理力学性能上(MOR,MOE,握钉力等)优于MDF和B类刨花板。     

利用毕赤酵母表达蚕丝丝素蛋白典型肽段的研究

设计并克隆了一个以源于蚕丝丝素蛋白结晶区的序列为GAGAGS（GlyAlaGlyAlaGlySer）的典型肽段为基本框架的基因,并导入毕赤酵母（Pichia pastoris）X33内进行了表达.研究表明,在X33酵母里可以正确表达目的蛋白Bm f31D1-8,而且获得了0.202g/L的表达效率.     

弱刚性零件夹紧顺序禁忌搜索优化方法研究

对于弱刚性零件精密加工而言,夹紧顺序对加工精度有很大的影响.针对夹具元件的夹紧顺序优化问题,建立了夹紧顺序与工件-夹具系统变形量之间的数学模型,并将夹紧顺序作为设计变量,基于禁忌搜索算法,对夹紧顺序的选择进行优化,达到减小夹具-工件系统的变形的目的,并给出实现所提方法的夹紧顺序优化的具体实例.结果表明,该方法对夹具元件...     

乙酰丙酮分光光度法测定纤维板甲醛释放量的不确定度评定

文章依据GB／T17657—1999对用于测定纤维板中有害物质甲醛的乙酰丙酮分光光度法的不确定度进行了研究。建立了数学模型,详细分析了测定过程中影响结果的各个分量,并对各不确定度分量进行评定,计算出了该法的合成不确定度和扩展不确定度。     

生物表面活性剂应用概述及其发展前景

随着人们崇尚自然和环保意识的增强,生物表面活性剂将成为化学合成表面活性剂的理想替代品,并有更加广阔的应用前景及发展潜力.本文介绍了生物表面活性剂的特性及其生产制备方法,并综述了近几年生物表面活性剂在石油、洗涤、医药、食品等工业领域的应用与研究进展,主要介绍了利用生物表面活性剂在提高石油采收率等方面的应用,探讨了今后生物表面活性剂的主要发展方向.     

Rejection of As(III) and As(V) from arsenic contaminated water via electro-cross-flow negatively charged nanofiltration membrane system

A specially designed electro-cross-flow nanofiltration (NF) membrane system was used for this investigation. To enhance the rejection of arsenic ionic species like H₂AsO₄⁻, a NF membrane having a negative surface charge was fabricated via the interfacial polymerization process. The membrane was characterized by SEM, AFM, surface charge density, molecular weight cut-off (MWCO), total and skin thickness and pure water flux. The parameters that affected the rejections of As(III) and As(V) were studied; they included the initial arsenic concentration, the applied potential, pH of the feed, the cross-flow filtration pressure and the presence of different salts in the feed. Among those parameters, the pH of the feed greatly affected As(V) rejection; As(V) ([As(V)]_o = 1000 ppb) rejection was increased from 72.3 to 98.5% when pH of the feed was changed from 3.0 to 10.0. This might be due to the fact that higher pH enhanced the formation of negative divalent anion like HAsO₄²⁻ which should be rejected more effectively by the negative surface charge of the NF membrane. Beside the effect of the negative surface charge of the membrane, applied potential increased the As(V) rejection by 48.2% when the applied potential was increased from 0 to 2.0 V for a feed containing 1000 ppb initially. For the same change of applied potential rejection of As(III) was increased from 52.3 to 70.4%; this might be the result of the formation of anionic species like H₂AsO₃⁻ from the neutral molecule of H₃AsO₃ by the applied potential.     

Microstructure and multifunctional properties of liquid + polymer bicomponent structural electrolytes: Epoxy gels and porous monoliths

Multifunctional structural batteries and supercapacitors have the potential to improve performance and efficiency in advanced lightweight systems. A critical requirement is a structural electrolyte with superior multifunctional performance. We present here structural electrolytes prepared by the integration of liquid electrolytes with structural epoxy networks. Two distinct approaches were investigated: direct blending of an epoxy resin with a poly(ethylene‐glycol) (PEG)‐ or propylene carbonate (PC)‐based liquid electrolyte followed by in‐situ cure of the resin; and formation of a porous neat epoxy sample followed by backfill with a PC‐based electrolyte. The results show that in situ cure of the electrolytes within the epoxy network does not lead to good multifunctional performance due to a combination of plasticization of the structural network and limited percolation of the liquid network. In contrast, addition of a liquid electrolyte to a porous monolith results in both good stiffness and high ionic conductivity that approach multifunctional goals. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42681.     

An Amphiphilic BODIPY‐Porphyrin Conjugate: Intense Two‐Photon Absorption and Rapid Cellular Uptake for Two‐Photon‐Induced Imaging and Photodynamic Therapy

The new amphiphilic BODPY‐porphyrin conjugate BZnPP and its precursor BZnPH were synthesised, and their linear and two‐photon photophysical properties, together with their cellular uptake and photo‐cytotoxicity, were studied. This amphiphilic conjugate consists of a hydrophobic BODIPY moiety and a hydrophilic tetra(ethylene glycol) chain bridging a cationic triphenylphosphonium group to an amphiphilic porphyrin ZnP through acetylide linkers at its meso positions. A large two‐photon absorption cross‐section (σ=1725 GM) and a high singlet oxygen quantum yield (0.52) were recorded. Intense linear‐ and two‐photon‐induced red emissions were also observed for both BZnPP and BZnPH. Further in vitro studies showed that BZnPP exhibited very efficient cellular uptake and strong photocytotoxic but weak dark cytotoxic properties towards human breast carcinoma MCF‐7 cells. In summary, the two‐photon‐induced emission and the potent photo‐cytotoxicity of BZnPP make it an efficacious dual‐purpose tumour‐imaging and photodynamic therapeutic agent in the tissue‐transparent spectral windows.     

新荧光试剂5－（4＇－硝基－2＇－羧基苯基偶氮）－2－硫代－4－噻唑啉酮的合成及其应用研究

报道了５－（４＇－硝基－２＇－羧基苯基偶氮）－２－硫代－４－噻唑啉酮（４ＮＲＡＣＰ）的合成。经柱层析提纯，用元素分析、ＩＲ、１ＨＮＭＲ和ＭＳ确证了其结构，研究了荧光性质，发现该试剂在溴代十六烷吡啶存在下，在无水乙醇溶液中与Ｅｕ（Ⅲ）形成稳定的荧光螯合物，λｅｘ／λｅｍ＝２９０ｎｍ／３４０ｎｍ，其线性范围为１．０×１０－８～１．０×１０－６ｍｏｌ·Ｌ－１，检测限为１．５×１０－１０ｍｏｌ·Ｌ－１。测定了人工合成样品中的铕，结果满意。     

入口旋流对均一粒径液滴喷雾干燥塔影响的数值模拟

均一粒径液滴喷雾干燥塔（MDSD）在生产均匀尺寸颗粒产品中发挥着较大优势,进一步优化其干燥过程操作尤为重要。集成离散相（DPM）和反应工程法（REA）干燥方法,通过耦合分散室和主干燥室模型,本研究开发了完整的MDSD三维计算流体力学模型。并系统探究了在干燥过程中分散气旋流、热空气旋流以及二者共同旋流对颗粒运动和最终干燥效果的影响。模拟结果表明,在30°入射角下加入旋流效果最优。同时引入分散室和干燥室旋流后发现,同向旋流比反向旋流带来的干燥效果提升2%,更比无旋流操作下的干燥效果提升30%。欲达到同样的干燥效果,引入同向旋流,塔身可缩短近12%。