抗菌剂改性纤维素物料及其抗菌性能(Ⅱ)--改性纤维素物料抗菌素的释出及其抗菌性能

抗菌剂(CA)改性棉纱布(CM)和漂白棉布(CC)系经CA与CM和CC相互吸附作用而制成.本文研究了在不同pH值溶液中抗菌素释出状况.试验结果证明,在pH＝7.0时抗菌素释出量最大.改性纤维素物料的微生物试验表明其具有抗菌性能,作为重要医疗包扎物品,具有实际应用价值.     

改性脲醛树脂的合成及其对木材改性效果试验

以聚顺丁烯二酸二乙醇酯（ＰＭ）和三聚氰胺（Ｔ）分别改性脲醛树脂（Ｕ－Ｆ），合成了两种稳定改性脲醛树脂－ＰＭ－Ｕ－Ｆ和Ｔ－Ｕ－Ｆ，考察了改性树脂中ＰＭ的含量和Ｔ／Ｕ摩尔比对木材改性效果的影响，试验结果表明，这两种改性脲醛树脂对板栗木、青岗木均有良好的改性效果。     

Accoya改性木材

新西兰：试验表明，Accoya改性木材（来自可持续经营林区的针叶材经Accoya技术处理）具有优良的耐久性。Scion，以前的新西兰林业研究所（New Zealand Forest Research Institute）对Accoya改性木材和merbau、cedar、teal（、cypress等几种木材和CCA处理木材进行了历时5年耐久性比较试验，结果表明，Accoya改性木材的状态显著优于其他样品。Accoya改性木材样品只有2个有轻微腐朽，     

酯化改性铁杉木屑制备重金属吸附剂及其吸附性能

木屑是一种常见的农林废弃物,来源广泛、价格低廉。木屑作为一种天然的生物质材料对水中的重金属离子有一定的吸附能力,但吸附效率较低。为提高木屑的吸附效率,实现农林废弃物的资源化利用,以铁杉木屑、2-氨基对苯二甲酸(2-ATP)、2-巯基丙酸(2-MPA)为原料,制备2-氨基对苯二甲酸改性铁杉木屑(AmS)和2-巯基丙酸改性铁杉木屑(MmS)两种酯化改性的新型吸附剂,并研究它们对溶液中Hg~(2+)的吸附性能。考察Hg~(2+)初始浓度、溶液p H、干扰离子以及吸附时间等对吸附性能的影响,结果表明:两种吸附剂在pH 4～8时具有较高的吸附性能,在pH 5时,AmS和MmS吸附剂的最佳吸附效率分别为93.3%和95.5%;当溶液中存在0.2 mol/L的干扰离子Ca~(2+)时,AmS和MmS吸附剂的吸附效率仍能维持在70.4%和73.4%;吸附剂的动态吸附行为均符合伪二级动力学模型,速率控制步骤为化学吸附过程,能够在60 min内快速到达吸附平衡;吸附剂的等温吸附曲线均符合Langmuir模型,为单分子层吸附。吸附试验表明,298 K时AmS和MmS吸附剂对Hg~(2+)的最大吸附容量分别为121.8和149.1 mg/g,远高于改性前的铁杉木屑(5.6 mg/g),具有良好的应用前景。     

抗菌剂改性纤维素物料及其抗菌性能(Ⅰ)——抗菌剂吸附研究实验(英文)

对纤维素物料与表面活性抗菌剂的吸附性能进行了研究。抗菌剂系乙烯基吡咯烷酮与巴豆酸共聚物和二甲基苄基烷基氯化物的合成聚合物 (具有广谱抗菌效果 )及其较低分子量的类聚物 (二甲基苄基烷基氯化物 )。确定纤维素物料对活性抗菌剂具有可逆吸附作用 ,并且决定于初始溶液浓度     

树皮的化学改性及其吸附特性研究

通过甲醛和环氧氯丙烷交联马尾松树皮，得到两种改性树皮；甲醛改性树皮（简称FMB）和环氧氯丙烷改性树皮（简称EMB）。讨论了不同改性条件对树皮得率的影响，研究了FMB、EMB对阳离子型染料碱性桃红和重金属离子铜离子的吸附特性，实验结果表明：（1）通过上述改性，可改善树皮的化学稳定性，避免有色物质的流出；（2）与未改性树皮相比，FMB、EMB对碱性桃红的吸附容量提高了约50%，达95mg/g；对铜离子的吸附容量提高了约56%，达78mg/g；（3）两种改性方法相比，吸附容量相近，但甲醛法改性成本低廉，污染少，综上所述，FMB、EMB是一种具有潜在应用价值的水处理材料。     

抗菌剂改性纤维素物料及其抗菌性能(Ⅰ)--抗菌剂吸附研究实验

对纤维素物与表面活性抗菌剂的吸附性能进行研究。抗菌剂系乙烯基吡咯烷酮与巴豆酸共聚物和二甲基苄基烷基氯化物的合成聚合物及其较低分子量的类聚物。确定纤维素物料对活性抗菌剂 可逆吸附作用，并且决定于初始溶液浓度。     

喷雾干燥法制备改性食用微晶纤维素粉末

通过对改性食用微晶纤维素溶液进行二流体和高速旋转盘式喷雾干燥试验，研究了改性食用微晶纤维素的喷雾干燥特性，获得了改性食用微晶纤维素的经济运行的优化喷雾干燥工业化条件和获取细粉的优化喷雾干燥工艺条件。     

改性玉米芯活性炭对镉的吸附性能研究

利用农业固体废物玉米芯作原料制备了活性炭,通过吸附热力学和吸附动力学过程,探讨了改性玉米芯活性炭对Cd²⁺模拟废水的吸附性能研究,以及考察了溶液pH值、活性炭投加量和温度对活性炭吸附Cd²⁺的影响。研究结果表明:磷酸改性600℃下裂解的活性炭吸附能力最好;改性玉米芯活性炭对Cd²⁺的吸附等温线更符合Freundlich模型;改性玉米芯活性炭对Cd²⁺的吸附动力学过程用准二级动力学模型能更好地拟合;经过单因素影响试验的研究表明,溶液初始pH值为6、活性炭投加量为0.01g、吸附温度为40℃时,活性炭的吸附效果最好。     

脲醛树脂浸渍轻木改性工艺及性能研究

对脲醛树脂（UF）浸渍改性轻木木材工艺、超临界CO2处理对轻木木材的浸渍性影响以及浸渍改性轻木木材的物理力学性能进行了研究。不同超临界CO2处理和浸渍工艺条件对改性材的增重率、体积湿胀率和顺纹抗压强度均有影响,与其素材相比,浸渍改性轻木木材的尺寸稳定性和力学性能显著提高,在显微镜下观察到有较多树脂分布在导管和木射线细胞中。     

Solubility of wood-cellulose in LiCl/DMAC solvent system

A LiC1/DMAC solvent system was used to dissolve wood-cellulose with aims to broaden its application in preparing functional materials of modified wood-cellulose. We studied the dissolubility complexion of wood-cellulose in a LiC1/DMAC solvent system, made sure of the important function of LiC1 in a cellulose solvent, and further confirmed its dissolution mechanism via the measurement of infrared spectra of soluble products. The study results are as follows： first, LiC1 salts, which can form intermediate complexes with cellulose, have played an important role in the LiC1/DMAC solvent system, and their solubility performance is en- hanced by reducing the hydrogen bond effect between cellulose molecules; second, the non-aqueous solvent system is a better method for dissolving wood-cellulose in homogenous phase. As found in infrared spectra, the absorption intensity of hydroxyl groups （broad peaks： 3,400 cm^-1） decreased greatly in cellulose macromolecules. This is because the degree of association between the hydroxyl groups of cellulose macromolecules is reduced, due to the destruction of the hydrogen bonds. Lastly, wood-cellulose can be dissolved in a LiC1/DMAC solvent thoroughly and efficiently, and can provide a better solvent system for homogeneous synthesis in the preparation of new functional materials via modified wood-cellulose.     

聚乙烯亚胺-纤维素的合成及对胆红素吸附性能

以聚乙烯亚胺(PEI)为功能基团、微晶纤维素(MCC)为载体通过环氧氯丙烷将PEI接枝到MCC上,制得功能高分子吸附材料PEI-MCC,通过红外光谱、元素分析、X射线衍射对PEI-MCC进行结构表征;测定其对胆红素的吸附性能。结果表明PEI-MCC的合成条件为:在N2保护下,环氧化纤维素(EC)与PEI的质量比为1∶6,反应介质为pH值11的氢氧化钠水溶液40 mL,反应温度70℃,反应时间12 h;过滤产物,水洗至中性,40℃真空干燥24 h,得微黄色固体粉末PEI-MCC,此时结晶度为78.36%,含氮量5.27%。静态吸附测得PEI-MCC对胆红素吸附容量为9.23 mg/g,吸附达平衡的时间为4 h。     

硬脂酸/TiO_2/CNF超疏水复合材料的制备与表征

研究了一种利用硬脂酸对纳米二氧化钛(Nano-TiO_2)和纤维素纳米纤维(CNF)复合物进行有机表面修饰的新方法,主要包括纳米二氧化钛、纤维素纳米纤维的制备和利用硬脂酸对Nano-TiO_2/CNF复合体系进行有机表面修饰制得超疏水材料三个工艺过程。通过傅里叶变换红外光谱仪(FTIR)和场发射扫描电子镜(SEM)等对所得的样品进行表征,得出硬脂酸中的—COOH基团与TiO_2/CNF复合体系表面的—OH基团发生脱水反应,并将疏水性—CH_3基团引入复合体系中,复合体系表面构建的纳米级粗糙结构协同体系内引入的疏水基团使最终产物具有超疏水性。     

超疏水纤维素复合气凝胶的制备及其油水分离

纤维素气凝胶因具有强亲水性和低油水选择性,且目前纤维素气凝胶表面的疏水化处理过程较冗长,限制了其在油水分离领域的应用。为了解决上述问题,笔者以硫酸水解微晶纤维素制备得到的纳米纤维素(CNC)为原料,利用甲基三甲氧基硅烷(MTMS)在水相中对其进行硅烷化改性,通过冷冻干燥得到了硅烷化纤维素复合气凝胶。结果表明:所制备的纤维素复合气凝胶具有轻质、多孔特性,随着MTMS添加量的增加,密度逐渐升高(≤0.012 0 g/cm^3),孔隙率略有下降; MTMS的加入对纤维素复合气凝胶的微观形貌影响不大,其骨架结构以二维片层形貌为主,聚甲基硅氧烷均匀地包覆在纤维素片层表面; MTMS的加入使纤维素复合气凝胶的热稳定性明显提高,且未改变纤维素气凝胶的晶型结构,但导致其结晶度逐渐下降。纤维素复合气凝胶的表面接触角随着MTMS添加量的增加而升高,最高达到153.7°,表现出优异的超亲油/超疏水性能。作为吸油材料,超疏水纤维素复合气凝胶不仅可以吸附多种油类和有机溶剂(吸附容量达到52～121 g/g),而且表现出很好的循环使用性能。     

Newly developed nanocomposites from cellulose acetate/layered silicate/poly(ε-caprolactone): Synthesis and morphological characterization

New biodegradable cellulose acetate/layered silicate grafted poly(ε-caprolactone) [(CA/layered silicate)-g-PCL] nanocomposites were prepared by in situ polymerization of ε-caprolactone in the presence of cellulose acetate (CA) and organically modified layered silicate (OMLS). The structures of the resulting composites were investigated. X-ray diffractometry was carried out to survey general structural features of (CA/OMLS)-g-PCL nanocomposites, and revealed that OMLSs having hydroxyl groups in the organic modifiers greatly altered the layered silicate structure by monomer intercalation and successive exfoliation through its polymerization. Two of the representative cases were characterized by wide-angle and small-angle X-ray scattering analyses with a synchrotron source. The morphology of these nanocomposites was further examined by transmission electron microscopy. When SPN, one of OMLSs having one hydroxyl group in its modifier, was used, the silicate layers could not be dispersed thoroughly, but existed as aggregates consisting of several silicate layers. Among them, the crystal growth of PCL developed by transcrystallization, where the crystal growth was restricted in the confined space. When Cloisite 30B, having two hydroxyl groups within the modifier, was used, the silicate layers forming the clay were dispersed completely in the composite and random orientation of the OMLS was observed.     

人心果原生质体分离初探

以人心果幼嫩叶片组织为材料,研究了酶液组合、酶解时间、酶液中甘露醇含量、pH值、温度等因素对其原生质体分离的影响,结果表明:以3%纤维素酶R-10+0.4%果胶酶Y-23为混合酶液,0.6 mol.L-1甘露醇为渗透压稳定剂,pH 5.6的酶液组合,在28℃的黑暗条件下振荡,酶解时间2 h,分离出的原生质体产量最佳,可达到12.4×106个.g-1。     

Organic Matter Added to Bareroot Nursery Beds Influences Soil Properties and Morphology of Fraxinus pennsylvanica and Quercus rubra Seedlings

Bareroot hardwood seedling production involves intensive soil management. To increase soil organic matter (OM), nurseries commonly grow a cover crop for 1 year after every 1–2 year of seedling production. Raising soil OM levels can also be achieved through addition of soil amendments. We studied the influence of chicken manure (CM) and composted leaf, tree, and lawn trimmings (Cp) on soil properties and morphology of green ash (Fraxinus pennsylvanica Marsh.) and northern red oak (Quercus rubra L.) seedlings. CM was applied at 725, 1450, or 2900 kg ha⁻¹ (CM725, CM1450, and CM2900, respectively) and Cp was applied at 200 m³ ha⁻¹. Addition of CM and Cp significantly raised soil OM levels and altered soil chemical properties compared to the control (Ctrl). Root-collar diameter increased with addition of CM1450, CM2900, or Cp compared to CM725 or Ctrl plots for northern red oak, but was largest in soils amended with CM2900 for green ash. Conversely, height was greatest with addition of CM725 for northern red oak, but green ash seedlings were shorter in Ctrl plots than in all amendments except for CM725. Root volume of green ash and northern red oak seedlings was positively influenced by addition of CM or Cp. Seedling responses to nursery soil amendments vary with different forms and amounts of OM. Benefits to seedling growth through application of appropriate materials in the proper balance can improve seedling morphological quality and positively influence soil chemical properties.