竹叶黄酮精华水乳液制备

基于竹叶黄酮具有防晒、保湿、美白等功效,在符合含量要求的范围之内,将竹叶提取物添加至水乳液中.首先对竹叶黄酮提取液进行了提取优化研究,并以芦丁作为标样,测定了竹叶提取液中黄酮含量。制备了竹叶黄酮精华水乳液并进行了乳液质感试用测评试验。结果表明:用20%(V/V)乙醇在25℃下超声提取20 min,竹叶黄酮提取效果较好。通过与市场上其它9个品牌的精华水乳液的质感试用测评,竹叶黄酮精华水乳液在使用质感上有较佳的表现,具有一定的市场前景。     

竹叶黄酮提取物的抑菌活性研究

采用稀释法研究了竹叶黄酮提取物的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）,并采用滤纸片法对竹叶黄酮提取物及其水解产物的抑菌活性进行了对比研究。试验结果表明竹叶黄酮提取物对藤黄微球菌、沙门氏菌、马红球菌、痢疾志贺氏菌、柠檬酸杆菌的抑菌效果及杀菌效果较好,其中竹叶黄酮提取物水解产物对藤黄微球菌的抑菌杀菌效果尤为明显,...     

竹叶黄酮壳聚糖缓释微球的制备及其性能研究

以壳聚糖为载体材料,戊二醛为交联剂,竹叶黄酮作为模型药物,采用乳化交联法,制备了载竹叶黄酮壳聚糖缓释微球。研究了载药比对微球的形貌、药物收率、包埋率和载药量的影响。结果表明:竹叶黄酮-壳聚糖微球呈规则球形,粒径10~50μm;竹叶黄酮经壳聚糖加载后,其释放时间长,释药均匀,具有良好的缓释性能。     

氧化石墨烯辅助乙醇提取竹叶黄酮

采用氧化石墨烯(GO)辅助乙醇回流提取竹叶黄酮,通过部分析因-响应面法得到提取竹叶黄酮的最优条件,分析了提取机理.结果表明,最优提取条件为温度82℃、时间86 min、乙醇浓度80%(Φ)、液固比17 m L/g,GO加入量为1.5 mg/g(干物料),该条件下竹叶黄酮的提取率可达88.4%,比乙醇回流提取高约10.6%.GO能水解植物细胞壁,降低纤维素的结晶度和晶粒尺寸,使传质阻力减小,从而提高竹叶黄酮的提取率.     

高品质竹叶黄酮的筛选及测定方法的比较

以不同产地竹叶为原料,对27个品种竹叶中黄酮活性组分的含量进行了测定,黄酮的质量分数为0.50%～1.72%,其中筛选出黄酮含量较高的是淡竹、绿竹和毛竹,成为工业上提取竹叶黄酮活性组分的最佳原料,而水竹黄酮含最虽高,但是分布较少.选用分光光度法和高效液相色谱法,对比研究竹叶中黄酮含革的差异性,确立了定量测定方法.NaNO<,2>-Al(NO<3>)<,3>-NaOH比色法测定结果偏高,以荭草苷、异牡荆苷为标准品,用C18ODS色谱柱,以V(甲醇)∶V(水)=50∶50为流动相,以360nm为检测波长,测定的竹叶中黄酮含量为5.9～13.1 mg/g.HPLC法测定结果更为可靠、准确.     

竹叶黄酮的提取、纯化及抗氧化性能研究

对竹叶中的黄酮类化合物进行提取、纯化及抗氧化性能研究。考察了大孔树脂对竹叶黄酮的吸附、解吸工艺参数,当黄酮上样量流速为1.0 m L/min,pH为5.0时,黄酮吸附率最高为80.13%。当洗脱剂乙醇流速为1.5 m L/min,乙醇浓度为60%时,黄酮解吸率最佳为90.6%。竹叶黄酮在光照、强酸、强碱条件下,自由基清除率下降明显。     

竹叶黄酮提取分析方法的研究及其新进展

从竹叶黄酮的基本性质着手,根据其溶解性,显色反应等特性,选取适当的提取方法。综述了五种应用较广泛的提取新方法、新技术,及分析方法,并简要论述了各种新技术和方法的原理以及应用于竹叶黄酮工业生产方面的情况。     

竹叶黄酮护肤霜功效的研究

将竹叶黄酮添加到护肤霜基质中制得竹叶黄酮护肤霜,按有关标准对产品进行了性能测试和评价.护肤功效检测表明,含质量分数为1.5％的竹叶黄酮护肤霜在UVB区的平均吸光度为1.273,在UVA区的防晒效果达到三星级,具有较好的防晒功效;有优良的保湿功效;能显著降低皮肤黑色素含量而美白皮肤;可改善皮肤纹理度,降低皮肤粗糙度;增加皮肤弹性;且人体试验安全、无刺激性,是一种天然的化妆品功能性成分添加剂.     

壳聚糖絮凝竹叶提取液及机理探讨

以澄清率和黄酮保留率为评价指标,考察了絮凝剂种类与用量、溶液pH值、絮凝时间与温度等因素对竹叶醇提取水溶液絮凝效果的影响。结果表明,壳聚糖絮凝效果明显优于明胶;单因素及正交实验法得到壳聚糖絮凝的较优工艺条件为:溶液pH值5.5,壳聚糖质量浓度为0.1mg/mL,40℃下絮凝10min,静置2h,此时竹叶醇提取水溶液的黄酮保留率为95.8%、澄清率为95.0%。且壳聚糖对竹叶醇提水溶液的絮凝效果优于竹叶水提液和醇提液。Zeta电位和傅里叶红外变换(FT-IR)光谱分析表明,壳聚糖通过电中和反应和吸附架桥作用除去竹叶提取液中的脂类、鞣酸类、蛋白质、多糖和小分子萜类等杂质,提高溶液的澄清度,同时对竹叶黄酮有很好的保留作用。     

竹叶黄酮在护肤品中防晒功效的初步评价

考察竹叶黄酮对紫外线辐射的防护效能。将竹叶黄酮添加到基质霜膏中制得护肤霜,采用紫外分光光度法,以紫外吸收值(透光率)为指标,对护肤霜的防晒效果进行评价。结果表明,在测试时间内,含竹叶黄酮1.0%和2.0%的护肤霜都能有效抵抗UVB辐射,按照布特星级分类标示,对UVA辐射的防护可达到三星级。竹叶黄酮可作为护肤品中的防晒功能添加剂。     

微波辅助提取竹叶黄酮的研究

用微波辐射技术辅助乙醇提取竹叶总黄酮的结果表明,微波辅助萃取的最佳工艺条件为:固液比为1∶25(w/w),溶剂乙醇的体积分数为60%,微波功率为600 W,辐射时间为6 min。在此条件下,竹叶中的总黄酮提取率可达2.93%。     

Bio-derived sodium silicate for the manufacture of alkali-activated binders: Use of bamboo leaf ash as silicate source

Alkali activated binders are a promising alternative to the use of Portland cement in the manufacture of concrete for curbing CO₂ emissions. Novel sources of silicates have been investigated in recent years for reducing cost and environmental impacts associated with the use of chemical activators. This study describes the production of solid sodium silicate (SS) activating powder from bamboo leaf ash (BLA). Bamboo leaves were calcined at 550–800°C, mixed with NaOH pellets, and heated in an oven at 300°C. The obtained silicate powder was used for activating blended fly ash/slag samples. Mechanical and microstructural properties of BLA-based samples were compared to those of samples made with commercially available chemicals. The strength of BLA-activated mortars matched the commercially-sourced activators, being 25–30 MPa at 7 days and exceeding 40 MPa at 28 days. The microstructural analysis suggested that BLA-based SS showed a lesser degree of dissolution of precursors at 7 days, but the quality of the matrix was higher than that of NaOH-activated samples. These results confirmed that the reactivity of BLA-silicate powder was similar to that of commercial SS solutions, and show the potential valorization of future biomass renewable waste in the production of low carbon, alkali-activated concretes.     

竹材热解过程的动力学

在不同升温速率（5、10、20、30 K&#8226;min^-1）下,对竹材进行TG、DTG分析.试样从313～650 K的升温过程经历了水分析出﹑第一步热解和第二步热解过程.用Levenberg-Marquardt方法对非等温动力学过程进行数据拟合,结果表明,半纤维素在较低温度下热解,仅生成挥发性组分,表现为第一步热解,可以用简单一级反应描述;纤维素和木质素在较高温度下热解,表现为第二步热解,是竞争的平行一级反应,产物分别是挥发性组分和竹炭.第一热解过程与热解升温速率有关,而第二热解过程与升温速率无关.     

Performance of bamboo plastic composites with hybrid bamboo and precipitated calcium carbonate fillers

The influences of hybrid bamboo and precipitated calcium carbonate (PCC) fillers in a recycled polypropylene/polyethylene matrix on the properties of bamboo plastic composites were studied. Thermogravimetric and Fourier transform infrared analyses of both thermo‐mechanically refined bamboo fiber (RBF) and ground bamboo particle (GBP) showed relatively higher holocellulose content in RBF, and more effective silane grafting on the RBF surface. The raw PCC particles contained over 95% calcium carbonate, and had an agglomerated form consisting of particles with a mean diameter of about 1.2 microns. Compounding the PCC particles with the plastic resin helped separate and disperse them in the matrix. Measured flexural strength and modulus of PCC‐only‐filled composites increased significantly from 15 to 30% PCC content levels, while the tensile and impact strength of composites decreased with the addition of PCC. For composites with hybrid bamboo and PCC fillers, tensile and flexural moduli were improved with the increase of PCC content. After silane treatment, RBF‐filled composites showed noticeably increased mechanical properties compared with those of GBP‐filled composites. For modulus values, PCC–bamboo–polymer composites were 3–4 times higher than those of PCC–polymer composites at high PCC levels. POLYM. COMPOS., 2012. © 2011 Society of Plastics Engineers     

PEW-g-MAH改性竹粉对PVC材料加工性能的影响

采用自制的聚乙烯蜡接枝马来酸酐(PEW-g-MAH)对竹粉进行包覆改性,研究了竹粉用量对竹粉/PVC复合材料加工性能的影响,并通过SEM对其界面进行了观察。结果表明:①竹粉/PVC复合材料的平衡转矩、平衡温度、塑化时间均随竹粉用量的增加而增大;②与未改性竹粉相比,经过PEW-g-MAH处理的竹粉可降低竹粉/PVC复合材料的平衡转矩、平衡温度,稍微缩短塑化时间;③SEM照片表明,PEW-g-MAH不仅改善了竹粉在PVC基体中的分散性,而且提高了两者的相容性。     

BSL-based coatings for bamboo protection

Bhilawanut shell liquid is a natural product, and because of its phenolic nature it undergoes reactions similar to those of phenol. Surface coatings based on BSL were prepared from formaldehyde, styrene, hexamine, and epichlorohydrin for the protection of bamboo surfaces. BSL-based coatings were applied on bamboo and the performance of these coatings was evaluated by accelerated and chemical resistance tests. It was observed that these coatings can be used for the protection of bamboo from corrosive environments. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 487–493, 1998     

竹粉用量对PVC/竹粉复合材料力学性能的影响

采用自制的聚乙烯蜡接枝马来酸酐(PEW-g-MAH)改性竹粉,制成PVC/竹粉复合材料,研究了竹粉用量对PVC/竹粉复合材料力学性能的影响。结果表明:随着竹粉用量的增加,试样力学性能总体呈现降低的趋势;添加PEW-g-MAH改性竹粉的试样力学性能要明显优于添加未改性竹粉的试样。SEM分析表明:经PEW-g-MAH处理后,竹粉与PVC树脂的相容性得到改善,可提高试样的力学性能。     

培育竹业 循环发展

赤水丰富的竹资源经过现代化工业精深加工提高了产品附加值。以赤天化纸业公司为龙头的工业经济延长了产业链,推动赤水生态效益和经济效益走上了可持续发展的道路。实现了农民增收、企业增效、财政增长的良性循环。退耕还林激活了地方经济,激活了一方产业。     

环保抗菌纤维——竹纤维

介绍了我国自主开发的竹纤维的性能、制备及应用 ,对竹纤维的产品开发和应用进行了分析 ,指出竹纤维是一种环保抗菌纤维 ,其前景看好。