不同基质配方对辣椒穴盘育苗质量的影响

在温室条件下,以泥炭土和珍珠岩为主要原料,按照不同的比例配合,对不同基质配方对辣椒幼苗生长发育的影响进行了研究。结果表明:辣椒幼苗在珍珠岩含量为25%的复合基质(泥炭土:珍珠岩=3:1)中表现最好,幼苗生长简单指标和复合指标均高于用其它3种配方;珍珠岩含量为50%的复合基质(泥炭土:珍珠岩=1:1)对辣椒幼苗生长有明显的抑制作用;综合分析表明,泥炭土与珍珠岩按照3:1配比作为辣椒穴盘育苗基质效果最佳。     

Enzymatic activity as a parameter for the characterization of the composting process

Enzymatic activity (EA) was explored as a possible tool for composting characterization. Three composts (yard wastes, cotton wastes and a mixture of the two) were sampled during different phases of the process and divided in two fractions. The first was immediately analysed for microbial biomass C (B_C) and EAs (β-glucosidase, arylsulphatase, acid and alkaline phosphatase). The second fraction was air-dried prior to analysis for the same EAs and for organic C (C_ORG), total N (N_TOT), dissolved organic C (DOC), extractable C (C_E) and humic-like C (C_H).B_C decreased throughout the composting period (149 days), whereas EA in moist fractions stabilized between 50 (β-glucosidase, alkaline phosphatase) and 90 (arylsulphatase, acid phosphatase) days of composting.EA was always reduced by air‐drying (β-glucosidase: 40-80%; arylsulphatase: 10-50%; acid phosphatase: 10-70%; alkaline phosphatase: 50-90%), but this effect was less prominent as composting proceeded, especially for β-glucosidase and alkaline phosphatase.EA in air-dried samples displayed the same trend as in moist ones, except that there was a marked difference (47-66%) between initial and final activities of all four enzymes.EAs in air‐dried compost and content of humic-like substances showed a similar trend: a marked increase in the first 90 days of the process and no significant variations afterwards. This suggests that the formation of humic-enzymatic complexes has taken place and indicates that this process occurs almost totally during the first stage of composting.EA steadiness in air-dried samples occurred concurrently with the achievement of compost stability, as indicated by the conventional indexes (i.e. C_H, C_ORG/N_TOT). Therefore, the development of a stable enzyme activity in air-dried compost could represent a simple measure of compost stabilization in routine analysis of composting process.     

芦丁及芦丁金属配合物对木材霉菌的抑菌性初探

为探究新型木材防霉剂,采用抑菌圈法、载片观察法及木材防霉试验,探究芦丁及芦丁不同金属配合物对黑曲霉的抑菌效果。结果表明,芦丁-锰、芦丁-镁、芦丁-锌可以减少黑曲霉的菌丝数量,影响孢子的产生和成熟,对黑曲霉具有明显的抑制作用;芦丁、芦丁-铜、芦丁-铁可以影响黑曲霉的菌丝生长,但是对孢子的产生和成熟的影响较小,对黑曲霉的抑制作用不明显。浓度为1.6mg·mL-1的芦丁-锰、芦丁-镁、芦丁-锌浸注处理毛白杨的侵染值分别为0.67、1.33和1.50;芦丁、芦丁-铜、芦丁-铁浸注处理毛白杨的侵染值分别为2.33、2.50和3.33。芦丁-锰、芦丁-镁、芦丁-锌对黑曲霉具有较好的抑制效果,可用于制备木材防霉剂。本试验结果为芦丁金属配合物制备环保型木材防霉剂提供一定的理论依据。     

复杂基质的食品中甜蜜素的检测方法

介绍了一种复杂基质的食品中甜蜜素的快速气相色谱检测方法(GC-FID)。样品通过水提取后离心,用正己烷对提取液进行净化。取25 mL水相,先后加入5 mL 50 g/L的亚硝酸钠和5 mL 100 g/L的硫酸,密闭冰浴衍生0.5 h。经GC/MS定性,最终衍生产物为环己烷亚硝酸酯。对于10 g样品的检测限为1.5 mg/kg(信噪比>3.0),4个水平添加甜蜜素的回收率,范围为62.55%~106.71%,平均回收率为(80.89±9.63)%,平均变异系数为12.10%。本方法满足复杂样品中的低浓度的甜蜜素监测。     

1996～2006年福建省社会-经济-自然复合生态系统生态位变化分析

依据福建省的实际情况,建立了福建省社会-经济-自然复合生态系统生态位评价指标体系,并运用全排列多边形综合指数法对1996～2006年福建省社会-经济-自然复合生态系统生态位变化做出了定量分析.结果表明:1996～2006年资源生态位总体上是在较高水平上呈现波浪式上升,环境、经济、社会生态位总体上呈逐渐上升的趋势;综合生态位也呈逐渐上升的趋势,从1996年的0.28上升至2006年的0.66,上升了1.36倍.     

模块化数控编程在复杂零件中的应用

编程人员在进行手工编程时,遇到复杂零件往往无从下手,用常规的编程方法进行编程,数值计算相当繁琐,工作量大,很容易出错,且程序很难校对.针对此类问题,本文提出了一种模块化数控编程,并以一薄壁零件为例对模块化数控编程在复杂零件中的应用进行了探讨和阐述.在进行模块化编程时,首先对复杂零件进行分析,确定加工工艺过程,之后对零件进行模块化分析,将零件分成若干个模块,分别对每个模块进行编程,通过分析可以发现模块化编程省时快速,不容易出错,且程序容易校对,极大地提高了编程效率.     

低蛋白饲粮不同添加物对生长育肥猪生产性能的影响

本试验通过降低生长育肥猪饲粮蛋白质水平2个百分点,其它营养水平不变,并在低蛋白饲粮中添加赖氨酸及复合促生长剂1号,共5周的饲养进行对比试验。结果表明：在低蛋白饲粮中添加复合促生长剂1号,能够显著提高生长育肥猪的日增重、饲料转化率及经济效益,并能超过高蛋白饲粮组;在低蛋白粮中添加赖氨酸,可提高生长育肥猪的日增重、饲料利用率及经济效益,但达不到高蛋白饲粮饲喂水平。     

Effect of the Silicic Acid Polymerization Degree on the Coagulating Property of Polyalumium Silicate Chloride

Polyaluminum silicate is a new type of inorganic macromolecular flocculants, which is developed as a complex product in recent years on the base of polyalumium flocculant and polysilicic acid flocculant. Sodium silicate is diluted to the concentration of 3.0% SiO 2 with distilled water. The solution was adjusted to pH 4.5 with sulphate acid and kept at quiescency for different time to get polysilicic acid with different polymerization degrees. Using polysilicic acid prepared and aluminium chloride as materials, a series of polyaluminium silicate chlorides(PASC) with different basicities(B), Al/Si molar ratios and polymerization degree of silicic acid are prepared by copolymerization technique. The Al-Ferron timed complex colorimetric method is applied to characterize species distribution of PASC and to study its influence factors. The interaction between hydrolyzed aluminum species and polysilicic acid with different polymerization degrees in PASC is discussed.The flocculant prepared is applied to the treatment of commercial concrete wastewater. The turbidity removal of commercial concrete wastewater is up to 97% when a PASC, prepared with polysilicic acid of 145 min polymerization degree.     

沿海混盐水体褶皱臂尾轮虫的复合类群及其种群动态

于 2002年 7月至 12月对大连一沿海混盐水体中褶皱臂尾轮虫复合类群的种类组成和种群动态进行了研究。根据轮虫被甲的形态特点和测量结果, 鉴定出该复合类群中的 5个轮虫同胞物种: Bra chionusplicatilisYamamoto、B plicatilisMüller、B rotundiformisTschugunoff、B ibericusDalian、B hepato tomusDalian, 它们分属于L、SS和SM三大类群。对轮虫种群季节分布的研究结果表明, 该水体中褶皱臂尾轮虫复合类群的种群分布符合重叠模型假说, 通过应用灰色系统理论, 拟合计算出不同轮虫种群的增长率。文中讨论了轮虫复合类群形成的原因, 以及水体中生态因子对轮虫分布的影响。此外,文中还给出了这 5种轮虫形态分类的Fisher判别方程。     

Integrated Evaluation and the Physiological and Biochemical Responses of Semi-Wild Cotton under Complex Salt-Alkali Stress

[Objective] The genetic diversity of semi-wild cotton was abundant, so more new elite resistant genes could be found and applied to improve the resistance of cotton. The aim of this study was to primarily study on the regulation of response to salt-alkali stress, explore the method of integrated evaluation and characterize the resistance of semi-wild cotton. [Method] Four semi-wild and two cultivated Gossypium hirsutum accessions were evaluated for phonotypical, physiological and biochemical traits under alkali-salt versus normal conditions in hydroponic solutions. The alkali-salt tolerance was determined based on principal component analysis, cluster analysis, correlation analysis, grey rational analysis and analysis of variance. [Result] On the basis of the overall results, the alkali-salt stress tolerance of the six accessions was ranked as: Marie-galante85 > Latifolium32 > CRI16 > CRI12 > Latifolium40 > Latifolium130. Roots were found to be the most important responsive systems to complex alkali-salt stress. At seedling growth stage, the active scavenging system played a crucial role in response to alkali-salt stress. In addition, the salt tolerant and salt sensitive accessions showed different response tends towards leaf peroxidase, root ascorbate peroxidase and root catalase within 48 h, suggesting the accessions have different levels of response to salt stress. [Conclusion]Our study identified the most alkali-salt tolerant accessions and provided basic concept of complex alkali-salt tolerance mechanism within cotton accessions. And, our study provided a simple and rapid, highly accurate and precise method for evaluating salt resistance of cotton, and proved that the balance of ROS system play an important role in response to salt-alkali stress. Hence, mining of salt tolerant genes from these accessions may facilitate the development of novel salt tolerant variety.