河北省转基因抗虫棉花品种纤维品质分析

从2004年开始河北省棉花品种审定进入了除短季棉品种之外全部为转基因抗虫棉品种的新阶段,5年间共审定转基因抗虫棉花品种65个,本研究对其纤维品质性状进行了分析。结果表明:上半部平均长度集中在27.1~32.7 mm,86.2%品种属于Ⅱ型;比强度集中在24.6~32.0 cN/tex,53.85%品种属于Ⅲ型,没有Ⅰ型品种,20%品种低于Ⅲ型;马克隆值集中在3.6~5.3,13.84%品种属于Ⅰ型,83.08%品种属于Ⅱ型。2004-2007年,纤维品质逐年变好,但由于2007年吐絮期长时间降雨,造成2008年纤维品质出现了下滑。总的说来,我省转基因抗虫棉品种没有上半部平均长度≥31 mm,比强度≥34 cN/tex,马克隆值在3.7~4.2的综合表现Ⅰ型的品种,主要表现在比强度没有Ⅰ型品种,因而,我们的应该加强培育高比强的棉花新品种。     

利用微米木纤维定向重组技术形成超高强度纤维板的细胞裂解理论研究

采用人造板微观力学和木材细胞学理论，提出了一种利用定向重组微米木纤维技术形成超高强度人造板的细胞裂解理论和强度参数预测方法。应用提出的理论，可以根据纤维、木质素、细胞直径和排列的程度，建立理想状态下微米重组高强度定向纤维板木纤维细胞在定向重组微米技术形成超高强度人造板的细胞裂解理论，为人造板力学运用数学手段深入到细胞结构研究的深度提供了一种新的理论和方法。     

鹅掌楸种源材性遗传变异与选择

在鹅掌楸两个种及其杂种多地点７年生种源试验林中,随机抽取３块试验林共２８２株样本,分别遗行木材基本密度（ＢＤ）和纤维长度（ＦＬ）的测定分析,在分布型拟合与精度分析的基础上,进行一般线性方差模型分析,结果为：中国鹅掌楸种源间ＢＤ和ＦＬ均差异显著（a=0.05),５个北美鹅掌楸种源间ＢＤ和ＦＬ未达到显著差异,地点间差异及种源与地点的交互作用不显著,平均值Ｔ检测表明中国掌楸与北美鹅掌楸两种间ＢＤ和ＦＬ均不存在显著差异,鹅掌楸的ＢＤ总均值为0.397g/cm^3,ＦＬ总均值达１.603mm,属于中小密度,长纤维或近长纤维树种,差异分析揭示了种内差异是掌释属的主要变异来源,种内种源间存在选择的遗传基础,性状遗传相关分析认为,鹅掌楸ＢＤ和ＦＬ之间相互不密切（r=0.157),两本材料状与各生长因子间相关亦不密切,说明他们之间基因连锁不紧密,可独立选择。BD种源广义遗传力为H^2BD=0.65,受遗传控制较强,ＦＬ为Ｈ^FL=0.29,受遗传控制中偏弱,两性状年－年间遗传相关密切,在上述分析结果的基础上方３种标准进行了鹅掌楸属材料种源选择,其中,在“强度选择”条件下,选出ＢＤ优良的种源为庐山和桑植,ＦＬ优良的种源为浏阳和赣武夷,均为中国掌楸种源,北美种源虽然与中国种源在总体上不存在明显差异,但多数处于中等水平上,对照杂种夫性系ＢＤ和ＦＬ的均超过鹅掌楸性状总均值,但未超过最好的种源。     

闽南山地桉树纤维材优良无性系的选择研究

对福建漳州岩溪、天马 2个试验点 1 3个桉树纤维材无性系的生长性状、木材纤维形态和化学组分等性能进行测定与分析 ,并经多性状综合评判 ,选择出具有较高的生长量、生物量和纤维产量 ,适合闽南山地发展的C9、C1 0、EC1、EC3、C6共 5个纤维材优良无性系 ,其中尤以C9、C1 0、EC1三个无性系的各性状为最优。这 5个无性系 ,3a生年平均树高和胸径生长量、每株干材重量和纤维产量分别可达 3 93～ 6 60m、3 83～ 4 97cm ,9 71～ 2 0 48kg·a- 1 和 4 3 6～ 9 5 2kg·a- 1 ,而且木材纤维形态和化学组成等特性良好 ,可进一步扩大繁殖、推广应用。     

纤维性质对成纸性能的影响

对纤维的三个基本性质－长度、强度和粗度对纸性的影响进行了综述，着重讨论了对强度性质的影响。     

国内外竹材造纸及其经济效益评价

本文根据国内外(包括中国、印度、日本、孟加拉国、缅甸、菲律宾、澳大利亚、苏联等)报道的竹材制浆造纸方面资料综合而成。文章内容有引言、竹材纤维形态与化学成分、世界竹材造纸工业简况和造纸竹材利用的经济效益。文章列举大量事实说明造纸工业用竹材为原料比用针叶材或阔叶材经济效益高。     

毛竹材材性变异的研究

通过对毛竹材纤维形态，组织比量、纤维素含量和基本的分析测定，研究了不同年龄、不同胸径、竹秆不同部位栲生性状的变异特点结果表明，竹材纤维长度主要受竹秆部位的影响，与年龄和胸径无显著相关，组织比量与年龄无显著相关，与胸径有一定相关；纤维素含量和基本密度与年龄、胸径、竹秆部位均有关系，从材性变异特点来看，经营培育小径级毛竹对制浆造纸更有利。     

Effect of fibers on the flow property of turbulent fiber suspensions in a contraction

In the flow of turbulent fiber suspensions flowing through a contraction with rectangular cross-section, the Reynolds averaged Navier-Stokes equation with the term of additional stress resulting from fibers was solved with the Reynolds stress model to get distributions of the mean velocity, mean pressure, turbulent kinetic energy and turbulent dissipation. It is found that the mean velocities at exit are small around the center and large near the wall for higher concentration. Fibers reduce turbulent intensity and turbulent dissipation at central line, but enhance them over the cross section at exit. Fibers have no effect of restraint on the turbulence in the contraction flow. The additional stress resulting from fibers plays a role in the increase of drag.     

Effects of different sources of carbohydrates on intake,digestibility, chewing,and performance of Holstein dairy cows

To investigate the effects of different sources of carbohydrates on intake, digestibility, chewing, and performance, nine lactating Holstein dairy cows (day in milk= 100±21 d; body weight=645.7 ± 26.5 kg) were allotted to a 3 × 3 Latin square design at three 23-d periods. The three treatments included 34.91% (B), 18.87% (BC), and 18.86% (BB) barley that in treatment B was partially replaced with only corn or corn plus beet pulp in treatments BC and BB, respectively. The concentration of starch and neutral detergent soluble carbohydrate varied (22.2, 20.2, and 14.5; 13.6, 15.9, and 20.1% of DM in treatments B, BC, and BB, respectively). Cows in treatment BB showed a higher DMI and improved digestibility of DM, NDF, and EE compared with treatments B or BC. Ruminal pH was higher in cows fed on BB (6.83) compared with those that received B or BC treatments (6.62 and 6.73, respectively). A lower proportion of propionate accompanied the higher pH in the BB group; however, a greater proportion of acetate and acetate: propionate ratio was observed compared with cows fed either on the B or BC diet. Moreover, cows fed on the BB diet showed the lowest ruminal passage rate and longest ruminal and total retention time. Eating time did not differ among treatments, rumination time was greater among cows fed on the BB diet compared with the others, whereas total chewing activity was greater than those fed on BC, but similar to those fed on B. The treatments showed no effect on milk yield. Partially replacing barley with corn or beet pulp resulted in an increase in milk fat and a lower protein concentration. Changing dietary NFC with that of a different degradability thus altered intake, chewing activity, ruminal environment, retention time or passage rate, and lactation performance. The results of this study showed that beet pulp with a higher NDF and a detergent-soluble carbohydrate or pectin established a more consistent ruminal mat than barley and corn, thus resulting in higher mean retention time and chewing activity, whereas no changes in 3.5% FCM and milk fat were observed.     

Fiber effects in nutrition and gut health in pigs

Dietary fiber is associated with impaired nutrient utilization and reduced net energy values. However, fiber has to be included in the diet to maintain normal physiological functions in the digestive tract. Moreover, the negative impact of dietary fiber will be determined by the fiber properties and may differ considerably between fiber sources. Various techniques can be applied to enhance nutritional value and utilization of available feed resources. In addition, the extent of fiber utilization is affected by the age of the pig and the pig breed. The use of potential prebiotic effects of dietary fiber is an attractive way to stimulate gut health and thereby minimize the use of anti-microbial growth promoters. Inclusion of soluble non-starch polysaccharides （NSP） in the diet can stimulate the growth of commensal gut microbes, inclusion of NSP from chicory results in changes in gut micro-environment and gut morphology of pigs, while growth performance remains unaffected and digestibility was only marginally reduced. The fermentation products and pH in digesta responded to diet type and were correlated with shifts in the microbiota. Interestingly, fiber intake will have an impact on the expression of intestinal epithelial heat-shock proteins in the pig. Heat-shock proteins have an important physiological role in the gut and carry out crucial housekeeping functions in order to maintain the mucosal barrier integrity. Thus, there are increasing evidence showing that fiber can have prebiotic effects in pigs due to interactions with the gut micro-environment and the gut associated immune system.