夏玉米花丝生长发育动态的研究

以不同穗型的玉米品种为材料,对玉米花丝生长发育动态进行研究.结果表明,花丝的发生首先开始于果穗中下部,其次是基部和中部,顶部花丝出现最晚;花丝出现集中在开始出现后的最初两天.吐丝后第三天生长速率最大.中下部花丝最先抽出苞叶,其次是基部和中部,顶部最晚.前两天的吐丝总量超过50%,尤以第二天吐丝百分率最高.衰亡过程也开始于中下部,基部和中部其次,顶部最晚;每一根花丝从基部开始衰亡,然后向顶部逐渐推移.果穗短粗型的品种花丝发育比较集中、吐丝较快;果穗细长型的品种花丝发育较缓慢,吐丝期延长,发育较晚的顶部花丝不易吐出苞叶。     

不同照明条件下靛蓝染色真丝织物的光老化速度及褪色机制分析

光老化是对丝绸文物的损害原因之一。研究靛蓝染色丝绸文物的光老化影响因素,有利于丝绸文物展览合理选择照明光源。采用荧光紫外灯、卤素灯和LED灯作为光源,模拟靛蓝染色丝绸文物在博物馆中的自然光老化过程。3种照明条件下靛蓝染料的褪色规律曲线表明:荧光紫外灯光对靛蓝染料破坏很严重,褪色很快;LED灯光在500~650 nm波段的相对能量较大,靛蓝染料在该波段有明显吸收峰,故在LED灯光照射下褪色较快;卤素灯光在能量较低的长波段对靛蓝染料的破坏作用不明显,因此褪色速度较慢。用高效液相色谱方法进一步分析靛蓝染料光老化的内在规律表明,靛蓝色谱峰面积的变化呈现很好的规律性,可以定量判断其光老化程度。通过色谱鉴定得到靛蓝染料成分的光老化产物为靛红成分。研究结果提示:采用卤素灯光作照明,更有利于靛蓝染色丝绸文物的保护。     

夏玉米花丝与穗轴伸长动态特征研究

利用中单909（ZD909）与安农591（AN591）两个夏玉米主栽品种,调查雌穗基、中、顶部花丝伸长动态与叶片和穗轴关系特征。结果表明,雌穗基、中部花丝比顶部花丝先发育、先吐丝、先脱落。当有效积温达到900℃·d时,基、中部花丝开始发育,穗轴发育到最终长度的10%;当有效积温达到1 000℃·d时,基、中部花丝发育到最终长度的70%、60%并开始吐丝,穗轴发育到最终长度的50%左右,吐丝期前后花丝发育长度占总长度的65%以上,是决定花丝伸出苞叶的关键时期;当有效积温达到1 100℃·d时,花丝发育完全并脱落,穗轴发育到最终长度的80%以上。ZD909和AN591两个品种上述关系表现出了一致性。随后运用Logistic模型对花丝与穗轴动态伸长进行拟合,量化了花丝和穗轴发育进程。本文精确描述了花丝与穗轴伸长特征,该研究结果可以应用到对花丝与穗轴伸长发育的模拟上。     

家蚕茧丝纤度的研究现状及相关探究

蚕丝作为重要的天然蛋白质纤维,在人类的生产和生活中被广泛的应用。而茧丝纤度是家蚕品种丝质性状之一,也是衡量茧质价值的重要标准。迄今为止,对于家蚕品种及雌雄间茧丝纤度的差异等相关研究较多,但在家蚕茧丝纤度性状基因效应及形成机制等前沿基础领域的研究还有很大不足,有待加强研究力度。     

城市紧凑度与经济发展水平关系研究——以“新丝绸之路”经济带为例

在充分理解城市紧凑度和经济发展水平以及耦合关系内涵的基础上,构建城市紧凑度和经济发展水平二者的评价指标体系,运用熵值法、耦合度模型及ArcGIS9.3对“新丝绸之路”经济带铁路沿线城市紧凑度与经济发展水平耦合关系进行分析.结果表明,“新丝绸之路”经济带铁路沿线城市紧凑度总体偏低,且城市之间存在较大差距;由于大部分城市地处西北地区,经济发展相对落后,区域经济发展水平差异明显;将城市紧凑度与经济发展水平之间的耦合关系分为协调型、磨合型、拮抗型和低水平耦合型4类,近80％的城市处于协调型和磨合型耦合阶段,城市紧凑度与经济发展水平总体上处于一种良好协调的状态.今后应该合理布局城市功能分区,提高土地利用效率,因市制宜,调整优化产业结构,促使二者更加协调发展.     

Preparation of silk sericin beads using LiCl/DMSO solvent and their potential as a drug carrier for oral administration

Silk sericin (SS) was fabricated into beads using LiCl/DMSO solution as a solvent. Up to 30 % (w/v) of SS could be dissolved within 3 hours, and the shape of solidified SS depends on the concentration of SS. Ethanol was the best coagulant among alcohols, making beads with suitable mechanical strength for further application. SS beads swell more at a pH above the isoelectric point (pl) than below the pl. The pH and the presence of an enzyme greatly affect the dissolution rate of SS beads. Whereas only 10 % of SS beads were dissolved at pH 2.2 in the presence of pepsin, more than 45 % of SS beads were dissolved at pH 7.4 in the presence of trypsin. The release of drug was suppressed in a stomach-like environment while promoted in an intestine-like environment.     

Sericin-fixed filk fiber as an immobilization support of enzyme

In this study, we attempted to evaluate a novel use of sericin-fixed silk fiber (SFx) as an immobilization support of enzyme. Sericin was fixed on the silk fiber using glutaraldehyde as a fixation reagent. After 6 hours of fixation, the degree of fixation increases linearly with linear decrease of the amount of bound α-chymotrypsin (CT). This suggests that the increase of the degree of fixation is due to the further crosslinking of free aldehyde groups on the surface of sericin-fixed silk fiber (SFx). Even though perfect fixation was not achieved, sericin did not dissolve seriously and could be removed by further washing. The specific activity did not differ significantly after 6 hours of fixation. The activity of immobilized CT on SFx decreased to its half after 6 hours of incubation at 50°C. However, it retained 78% of initial activity even after 1 hour of treatment with 100% ethanol. As a result, the SFx could be used as an immobilization support of enzyme in non-aqueous media at ambient temperature.     

Dyeing of cotton and silk yarn with the extracted dye from the fruit hulls of mangosteen,<Emphasis Type="Italic">Garcinia mangostana</Emphasis> linn

The extracted dye from the dried fruit hulls of mangosteen was used as a natural dye for the dyeing of cotton and silk yarn. The optimal conditions for dye extraction were to extract the dried fruit hulls of mangosteen at 80°C for 1 hour with a 15 % w/v citric acid solution in a 1:4 ratio of mangosteen powder to solvent. Cotton dyeing with the extracted dye from the dried fruit hulls of mangosteen was carried out at 60°C for 60 minutes with a material to liquor ratio of 1:25. The effect on dyeing of mordant type with different mordanting methods was studied. The results showed that the dyeing of cotton using the post-mordanting method with ferrous sulfate and calcium hydroxide not only provided better depth of shade but also provided better wash fastness and light fastness than with other mordants (alum; zinc tetrafluoroborate) or without a mordant. Good fastness properties were also obtained using a post-mordanted silk with calcium hydroxide.     

Crosslinking reaction of phenolic side chains in silk fibroin by tyrosinase

Tyrosinase oxidizes the tyrosyl residues in silk fibroin (SF) with oxygen, resulting in the production ofo-quinone residues. Subsequently, the inter- or intramolecular crosslinks are formed by reaction with amino groups in through nonenzymatic process. The measurement of oxygen consumption proved that the tyrosyl residues in SF were mostly oxidized to quinone residues by tyrosinase. The reaction mechanisms were proposed in this study and the crosslinking reaction ofo-quinone residues and the enzymatic oxidation of tyrosyl residues could be confirmed by the measurements of UV,¹H-NMR and GFC.     

Production and storage stability of non alcoholic banana beverage powder

Powder for an instant, non-alcoholic beverage formulation was manufactured by sundrying and ovendrying of a popular dessert (silk) banana variety. The reconstituted beverage was organoleptically acceptable. The effect of traditional sundrying on mats and ovendrying methods on product quality was investigated. Sundrying resulted in losses of Vitamin A, C and total sugar contents by 74, 91 and 63%, while ovendrying losses were 73, 90 and 62%, respectively. Nutrient losses during storage for three months in transparent polythene bags reached 93, 93 and 70% in sundried samples and 84, 99 and 55% in ovendried samples, respectively. The moisture content of sundried and ovendried samples increased by 12 and 17%, respectively, during storage. The increase in microbial load in this period was higher in sundried samples.