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81.
采用十二烷基二甲基甜菜碱对红薯渣(R)做两性修饰,修饰比例分别为0、100%和200%,将得到的3种两性修饰红薯渣(R、100BS-R和200BS-R)以1%质量分数加入紫色土(PS)中,制成PS(对照)、PSR、PS100BS-R和PS200BS-R 4种混合土样。用批量处理法探究各供试土样对Cu2+的吸附等温特征,并考察温度、pH值和离子浓度对Cu2+吸附的影响。结果表明:各混合土样对Cu2+的吸附等温线均符合Langmuir模型,最大吸附量为99.46 mmol/kg~136.53 mmol/kg,Cu2+吸附量呈现PS200BS-R>PS100BS-R>PSR>PS的趋势。温度和pH值升高均有利于Cu2+被吸附,当离子浓度为01 mol/L时吸附效果最佳。  相似文献   
82.
岷江干旱河谷甜樱桃发展优势及栽培技术研究   总被引:1,自引:0,他引:1  
岷江上游干旱河谷特有的生态环境条件适宜发展优质特色水果.甜樱桃作为该区域新兴特色水果之一,近5年来发展面积已超过了400hm2.甜樱桃的引种和规模化栽培表明,岷江上游干旱河谷区发展优质、高产甜樱桃具有独特的优势.总结了岷江干旱河谷栽培甜樱桃的成熟技术和管理措施,探讨了发展甜樱桃的巨大潜力,同时对存在的问题进行了分析,以期为汶川地震灾害农业产业的恢复重建和结构调整提出新的思路.  相似文献   
83.
甘薯块根腐烂真菌的分离和鉴定   总被引:1,自引:0,他引:1  
从腐烂甘薯块根中分离到4株丝状真菌,分别编号为SP-1、SP-2、SP-3和SP-4,它们都能在甘薯块根片上快速生长.将这4株真菌接种在PDA培养基上,观察其菌落形态和结构特征.提取4株菌的总DNA,利用真菌的18S rDNA通用引物进行扩增、克隆和测序,其18S rDNA序列的长度分别为1 810 bp、1 769 bp、1 768 bp和1 770 bp.将这些序列在GenBank中进行序列比对,获得的同源性较高的序列用于构建系统进化树.根据分子鉴定和形态观察的结果,SP-1菌株是匍枝根霉(Rhizopus stolonifer)SP-1,SP-2是尖镰孢(Fusarium oxysporum)SP-2,SP-3是康宁肉座菌(Hypocreakoningii)SP-3,SP-4是肉座菌属(Hypocrea),命名为Hypocrea sp.SP-4.  相似文献   
84.
马铃薯淀粉废水具有处理难度大、有机污染物浓度高等特点,属于高难度有机废水。为了有效的解决马铃薯淀粉废水造成的环境污染问题,采用强化厌氧膨胀颗粒污泥床组合好氧工艺对有机污染物质和氨氮的去除效能进行研究。研究结果表明-强化厌氧膨胀颗粒污泥床在最佳运行工况条件下(进水温度为30℃、外回流比为2和水力停留时间24 h),组合工艺出水COD质量浓度和氨氮浓度分别在92.35 mg/L和10.28 mg/L左右,去除率分别在98.85%和86.29%左右,出水水质能够满足《污水综合排放标准》(GB8978—1996)二级标准,说明该工艺是一种适用于马铃薯淀粉废水的处理技术。  相似文献   
85.
To better understand the interaction mechanisms of plant surfaces with polar organic compounds, sorption of 4-chlorophenol, 2,4- dichlorophenol, and 2,4,6-trichlorophenol by fruit cuticles (i.e., tomato, apple, and pepper), and potato tuber periderm were investigated. The roles of cuticular components (waxes, cutin, cutan and sugar) on sorption of chlorophenols are quantitatively compared. Cutin and waxes govern the sorption capacity of bulk apple cuticle by hydrophobic interactions. Potato periderm with highest sugar content exhibits the lowest sorption capability for the chlorophenols. With the increase of hydrophobicity (i.e., Kow ) of sorbate, the relative contribution of lipophilic components (wax, cutin and cutan) on total sorption increases, however, the ratios of Koc to Kow decreases due to increasing ionization degree of sorbates.  相似文献   
86.
Abstract

Fluazinam, a widely used pesticide in conventional potato cultivation, is effective against epidemics of the fungal disease late blight. To assess fluazinam persistence in soil, laboratory experiments were conducted with fluazinam added to soil as a pure chemical or contained in the commercial product Shirlan®. In a follow-up experiment, the persistence was monitored under constant temperature and water content conditions during a maximum period of 1?year. In an annual climatic rotation experiment, fluazinam added to soil was exposed to the year-round temperature and water content conditions occurring in the boreal zone. A third experiment was undertaken to clarify the effect of soil organic matter (SOM) on the recovery of fluazinam. In the follow-up and annual climatic rotation experiments, more than half of the added fluazinam was recovered after 1?year of incubation. The estimated half-life of fluazinam ranged between 355 and 833?days. The degradation of fluazinam was enhanced by an abundance of SOM, a warm temperature, and wetness. Additionally, in over half of soil samples collected from fields where potato had been intensively cultivated for many years, varying concentrations of fluazinam were detected. Fluazinam can carry over to the next growing season in professional potato production.  相似文献   
87.
甲壳素是一种天然的生物高分子 ,是仅次于纤维素的第二大可再生资源。系统介绍了提取甲壳素的原料来源及提取方法。对国内外甲壳素制取壳聚糖的方法和工艺条件作了详细的介绍 ,着重阐述了壳聚糖及其衍生物的生产方法以及在医药、食品、日化、农业、化工、环保、造纸、纺织等许多领域的应用现状和开发前景  相似文献   
88.
NaCl胁迫对甜高粱发芽期生理生化特性的影响   总被引:2,自引:0,他引:2  
王秀玲  程序  谢光辉  李桂英 《生态环境》2010,19(10):2285-2290
为筛选耐盐甜高粱材料,探讨NaCl胁迫对甜高粱发芽期生理生化特性的影响,研究了0、70、140、210 mmol.L-1NaCl胁迫对吉甜3、BJK156、甜132、凯勒、威利、考利、吉甜2、戴尔等8个甜高粱材料发芽率、发芽势、发芽指数、活力指数、芽长、根长、芽鲜质量、根鲜质量等8个指标盐害系数的影响,利用系统聚类分类法对甜高粱耐盐性进行聚类可分为3类:耐盐性最强的是甜132,耐盐性中等的是BJK156,耐盐性较敏感的是考利、吉甜3、吉甜2、戴尔、凯勒、威利。进一步研究了盐胁迫对甜高粱芽苗中丙二醛、可溶性蛋白含量及过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性的影响。结果得出:随着盐胁迫的加重丙二醛含量逐渐增加,可溶性蛋白含量逐渐减少。NaCl胁迫不同程度地提高了8个甜高粱材料POD、CAT、SOD活性,受3种NaCl质量浓度胁迫后8个甜高粱材料POD、CAT、SOD活性的变化趋势不同,这可能是它们耐盐差异的生理原因之一。另外,在3种NaCl浓度胁迫后甜132中的丙二醛增加量在8个材料中都是最低的,这与系统聚类分析得出甜132耐盐性最强的结论相吻合。研究认为丙二醛含量的变化可以作为筛选发芽期耐盐甜高粱品种的一个指标。  相似文献   
89.
A microwave technique was used to prepare foams from different potato starches in granular form, with varying amounts of amylose content, and water. In addition to native potato starch (PN), high amylose potato starch (HAP) and potato amylopectin (PAP) were used, as well as mixtures thereof. In all cases the native crystallinity of starch granules was lost upon microwave treatment and an amorphous material was created. An increased concentration of starch in the initial water dispersion resulted in a less dense foam structure. The potato amylopectin formed open cell foams, whereas increased amylose content, as in native potato starch, yielded a more compact structure with irregular pore shapes. The high amylose potato starch yielded a structure with hardly any porosity. Foaming experiments were done to compare pre-gelatinized and granular starches dispersed in water. The pre-gelatinisation did not affect the pore formation process. These experiments indicated that the molecular architecture of starch polymers is more important for foam formation than starch polymer organization in the granules. Studies of temperature profile and dry matter content during microwave treatment showed that water evaporates more rapidly from a high amylose starch solution than native potato starch and potato amylopectin solutions. Rheological measurements showed that the amylose solution had much lower viscosity than starch and amylopectin. This confirms that polymer – water interaction, such as in amylopectin solution, favours stabilization of bubbles formed upon boiling and evaporation of water, which yields high porosity materials.  相似文献   
90.
一株运动发酵单胞菌Zy-1快速生产乙醇   总被引:1,自引:0,他引:1  
经多次实验优化,得到运动发酵单胞菌Zy发酵葡萄糖生产乙醇较合适的条件.Zy的诱变菌株Zy-1在该条件下发酵葡萄糖生产乙醇比原始菌株更有较大优势.当葡萄糖浓度为200gL^-1时,发酵48h,乙醇浓度96.5gL^-1,残糖2.3gL^-1,发酵效率为94.42%.Zy-1发酵天然原料米粉、木薯、红薯干等,发酵时间44h,乙醇浓度达95gL^-1以上,发酵效率92%以上.发酵液用DNS法测定,还原糖约2gL^-1,残总糖因原料种类不同,其值有所差异(5~20gL^-1).经薄层层析分析,发酵液无葡萄糖,而是二糖、三糖等低聚糖.图2表5参12  相似文献   
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