森林景观界面研究概况

文章对森林景观界面的概念、由来、分类、结构与功能等进行了介绍与论述,对森林景观界面与边缘效应的关系进行了阐明,特别对森林景观界面的生态过程研究进展作了概括。森林景观界面生态过程研究主要集中在以下几个方面:生物多样性研究、土壤水分、土壤养分、光照辐射与温度、风及其他领域。文章还对森林景观界面的未来研究方向与趋势作了展望:未来的森林景观界面研究将主要聚焦于界面的结构、功能及形成维持机制的研究,景观界面与气候变化的研究,景观界面的生态过程研究。

外来杂草入侵的化学机制

由外来杂草入侵引发的严重生态和经济问题已倍受关注 .外来杂草在新生境成功入侵 ,除了具备一些基本的生物生态学特征外 ,还应具备一些特有的入侵机制 .阐明外来杂草的各种入侵机制可以为入侵杂草的预测和控制提供科学依据 .外来杂草只有在新生境中与原产地生物种间的相互作用中取得优势 ,才能定植并扩增种群而成功入侵 .在这些外来杂草和原产地生物种间的相互作用关系中 ,化学关系是不可忽视的方面 .目前研究已经证实 :植物的化感作用在外来杂草成功入侵中发挥着重要的作用 .事实上 ,植物也可以通过合成和释放特定的化学物质防御或抑制新生境的动物、植物和微生物 .外来杂草入侵的化学机制涉及到植物化学生态学的各个方面 .因此 ,外来杂草的化学生态学特征应作为入侵种预测的重要指标之一 ,外来杂草入侵的化学机制应是今后重要的研究方向

中国多孔菌名录

本文中的多孔菌系指广义非褶菌目中具有孔状子实层体的种类,按照现代分类系统包括担子菌门中多孔菌目、锈革孔菌目、褐褶菌目、糙孢孔目、革菌目、糙孢革菌目和红菇目中孔状子实体的种类,还有伞菌目、阿太菌目、鸡油菌目和木耳目中个别属,如网孔菌属、胶孔菌属、榆孔菌属、牛排菌属和纵隔孔菌属等的种类。基于作者采集的1万余号标本和国内主要标本馆标本的研究,对中国多孔菌的种类进行了系统总结,目前有604种多孔菌发现于中国,多孔菌数量位居世界第一。对中国多孔菌的名称按新近研究成果和最新命名法规(维也纳法规)进行了订正。对121种新拟了汉语学名。

Five supramolecular compounds of water-soluble sulfonylcalix[4]arenetetrasulfonate showing two calixarene conformations

Five new compounds of sulfonylcalix[4]arenetetrasulfonate (SC4AS), [H7Na(H2O)(3)(SC4AS)(phen)(5)](H2O)(11.9) (1), [H6Mn(H2O)(4)(SC4AS)(phen)(5)] (H2O)(12.7) (2), [Cu-4(SC4AS) (phen)(6)] (H2O)(4.5) (3), {[Cu (2)(SC4AS) (bpy)(2)][Cu(bpy)(2)(H2O)](2)} (H2O)(6.6) (4), and {[Zn-2(SC4AS) (phen)(2)][Zn(phen)(2)(H2O)(2)](2)} (H2O)(7) (5) (where phen 1,10-phenanthroline and bpy = 2,2'-bipyridine), were synthesized by a hydrothermal method and structurally determined by single crystal X-ray diffraction. The SC4AS ligand adopts partial cone conformation in compounds 1 and 2 and 1,2-alternate form in compounds 3-5. According to the structural analysis and density functional theory (DFT) calculations, we suggest that the metal can affect the conformation of SC4AS.

Enhanced charge collection in polymer photovoltaic cells by using an ethanol-soluble conjugated polyfluorene as cathode buffer layer

We report enhanced polymer photovoltaic (PV) cells by utilizing ethanol-soluble conjugated poly (9, 9-bis (6'-diethoxylphosphorylhexyl) fluorene) (PF-EP) as a buffer layer between the active layer consisting of poly(3-hexylthiophene)/[6, 6]-phenyl C61-butyric acid methyl ester blend and the Al cathode. Compared to the control PV cell with Al cathode, the introduction of PF-EP effectively increases the shunt resistance and improves the photo-generated charge collection since the slightly thicker semi-conducting PF-EP layer may restrain the penetration of Al atoms into the active layer that may result in increased leakage current and quench photo-generated excitons. The power conversion efficiency is increased ca. 8% compared to the post-annealed cell with Al cathode.

The preparation of sol-gel materials doped with ionic liquids and trialkyl phosphine oxides for Yttrium(III) uptake

A new material (IL923SGs) composed of ionic liquids and trialkyl phosphine oxides (Cyanex 923) for Y(III) uptake was prepared via a sol-gel method. The hydrophobic ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate (C(8)mim(+)PF(6)-) was used as solvent medium and pore templating material. The extraction of Y(III) by IL923SGs was mainly due to the complexation of metal ions with Cyanex 923 doped in the solid silica. Ionic liquid was stably doped into the silica gel matrix providing a diffusion medium for Cyanex 923, and this will result in higher removal efficiencies and excellent stability for metal ions separation. IL923SGs were also easily regenerated and reused in the subsequent removal of Y(III) in four cycles.

离子液基萃取金属离子的研究进展

室温离子液体作为一种新型绿色溶剂,因其具有不挥发、不易燃等重要特性,故近年来在各种金属离子液/液萃取领域的应用日益受到关注。本文系统评述了离子液基萃取金属离子的分配规律、萃取机理、缺陷和克服方法,并展望了该分离方法在环境分析化学领域的应用前景。

Application of room temperature ionic liquid-based extraction for metal ions

As a kind of novel green solvent, Room Temperature Ionic Liquids (RTILs) have been paid ever-increasing attentions in RTIL-based extraction for metal separation, since they have many unique proper-ties, such as non-volatile and non-flammable. The progress of that is mainly composed of the partition properties, mechanisms, defects, overcome methods and forecasts of the processes on the environmental analytical chemistry, has been reviewed.

Synthesis, structure and luminescence properties of zinc (II) complexes with terpyridine derivatives as ligands

Five zinc (II) complexes (1-5) with 4 '-phenyl-2,2 ':6 ',2 ''-terpyridine (ptpy) derivatives as ligands have been synthesized and fully characterized. The para-position of phenyl in ptpy is substituted by the group (R), i.e. tert-butyl (t-Bu), hexyloxy (OHex), carbazole-9-yl (Cz), naphthalen-1-yl-phenyl-amine-N-yl (NPA) and diphenyl amine-N-yl (DPA), with different electron-donating ability. With increasing donor ability of the R, the emission color of the complexes in film was modulated from violet (392 nm) to reddish orange (604 nm). The photoexcited luminescence exhibits significant solvatochromism because the emission of the complexes involves the intra-ligand charge transfer (ILCT) excited state. The electrochemical investigations show that the complexes with stronger electro-donating substituent have lower oxidation potential and then higher HOMO level. The electroluminescence (EL) properties of these zinc (II) complexes were studied with the device structure of ITO/PEDOT/Zn (II) complex: PBD:PMMA/BCP/AlQ/ LiF/Al. Complexes 3, 4 and 5 exhibit EL wavelength at 552, 600 and 609 nm with maximum current efficiency of 5.28, 2.83 and 2.00 cd/A, respectively.

Studied on the interactions of antibody-porphyrin by circular dichroism and ultraviolet-visible spectrophotometry

Circular dichoism and UV-vis measurements were used to study the interaction between porphyrin and monoclonal antibodies ( McAbs). McAbs-porphyrin complex formation is usually accompanied by significant bathochromic shift and hyperchromicity changes of the absorption maxima in the porphyrin soret band region. Induced CD spectra in the same region (350 similar to 450 nm) were detected upon complex formation. They follow Lamb-Beer's law and exhibit isosbestic behavior. Both the UV-Vis and induced CD spectra of the antibody: porphyrin complex remain unchanged over a broad pH range ( pH 6 similar to 11), indicating remarkable stability of the complex and reflecting the dominant role of hydrophobic interaction between the hapten benzophenone and the antibody combining site.

圆二色谱和紫外可见光谱研究抗体-卟啉的相互作用

圆二色谱 (CD)和紫外可见光谱 (UV VIS)可用来研究单克隆抗体 (McAb) 卟啉之间的相互作用。卟啉形成McAb 卟啉复合物 ,在Soret带区域最大吸收峰有显著红移和增色现象。在 3 5 0～ 45 0nm区域 ,形成复合物时能检测诱导的CD光谱。CD光谱遵守朗伯 比尔定律 ,显示等吸收行为。McAb 卟啉复合物的紫外可见吸收及诱导的CD光谱在pH 6～ 1 1的范围内保持不变 ,说明复合物异常稳定 ,也说明McAb 卟啉结合位点之间疏水相互作用是主要因素。

Crystal structure of a noval poly(aryl ether ketone) containing meta-phenyl linkage

Crystal structure of a novel aryl ether ketone polymer poly(aryl ether ketone ether ketone ketone containing meta-phenyl linkage)(PEKEKmK) was determined by means of WAXD and ED. An orthorhombic unit cell is proposed containing two chains with a=0.772 nm, b=0.604 nm and c=2.572 nm. According to the orthorhombic system, the 10 reflections of this polymer were indexed.

Crystal structure and variation in unit cell parameters with crystallization temperatures of poly (ether ketone ether ketone ketone)s containing meta-phenyl links (PEKEKmK)

The X-ray diffraction patterns of the crystalline aromatic ketone polymer PEKEKmK (aryl ether ketone ether ketone ketone polymer containing meta-phenyl links) have been investigated (for the chemical structure, see Formula). An orthorhombic unit cell is proposed to contain two chains with a = 0.772 nm, b = 0.604 nm and c = 2.572 nm. According to the orthorhombic system, the 11 reflections of this polymer were indexed. Meanwhile, variation in unit cell parameters with crystallization temperatures of PEKEKmK was also investigated. [GRAPHICS]

新型不同结构聚酯的生物降解

目的　探讨几种新型可生物降解聚酯类合物的结构及生物环境对降解规律的影响 ,为临床选择应用该类材料提供实验依据 .方法　将自行合成的聚己内酯 (PCL)、聚丙交酯(PL A)、以及它们不同摩尔比的共聚物 (PCL A2 / 1,PCL A1/2 )分别置于胆汁、胰组织悬液和血浆中 1～ 7d,植入兔肌肉内2 4wk,观察材料质量损失、超微形态变化和分子量变化 .结果　 PCL 在 2 4wk内各种性质变化最慢 :质量损失不明显 ,分子质量在胰腺悬液中下降 19.8% ,形态无明显变化 ;PCL A2 / 1在 2 4wk时质量损失 0 .5 % ,分子质量下降 6 1.7% ,材料断面出现蚀刻形态 ;PCL A1/ 2在 2 4wk质量损失 40 .4% ,分子质量下降 6 .6 % ,形态出现空洞、碎裂 ;PL A在 2 4wk质量损失 79.2 % ,分子质量下降 15 .1% ,形态完全降解 .结论　不同结构的材料在不同环境中体现不同的降解性质 .