铬天青S－溴化十六烷基三甲铵－乙醇高灵敏分光光度法测定植物和土壤水中铝

本文探讨了铝与铬天青Ｓ的最佳显色反应条件。当ｐＨ为６．５，在溴化十六烷基三甲铵（ＣＴＭＡＢ）和乙醇的存在下，铝与铬天青Ｓ形成绿色配合物，最大吸收峰位于６３５ｕｍ，表观摩尔吸光系数为１．６５×１０５Ｌ／ｍｏｌ·ｃｍ，铝含量在０～０．２４μｇ／ｍＬ范围内符合比耳定律。在本实验条件下，该方法具有良好的选择性，应用于植物和土壤水中铝的测定，结果满意。     

Vermicomposting leachate as liquid fertilizer for the cultivation of sugarcane (Saccharum sp.)

In vermicomposting, the main product is the worm casts, but a leachate is generated that contains large amounts of plant nutrients. This leachate is normally diluted to avoid plant damage. We investigated how dilution of vermicompost leachate combined with different concentrations of nitrogen (N) - phosphorus (P) - potassium (K) triple 17 fertilizer, and polyoxyethylene tridecyl alcohol as dispersant and polyethylene nonylphenol as adherent to increase efficiency of fertilizer uptake, affected sugarcane plant development. The vermicomposting leachate with pH 7.8 and electrolytic conductivity 2.6 dS m^?1, contained 834 mg potassium (K) l^?1, 247 mg nitrate (NO₃^?) l^?1 and 168 mg phosphate (PO₄^3?) l^?1, was free of pathogens and resulted in a 65% germination index. Vermicompost leachate did not inhibit sugarcane growth and mixed with 170 g l^?1 NPK triple 17 fertilizer resulted in the best plant development. No dispersant or adherent was required to improve plant height and stem development.     

Oxygen enrichment with magnesium peroxide for minimizing hypoxic stress of flooded corn

Flooding/waterlogging is a major factor responsible for hypoxic stress in agriculture. The aim of this study was to develop an effective oxygen buffer with magnesium peroxide (MgO₂) to generate hydrogen peroxide (H₂O₂) and release bioavailable oxygen. MgO₂ provided a relatively stable level (approx. 300 µM) of bioavailable oxygen. The oxygen‐buffer system is adjustable and controllable by adding Mg²⁺ or EDTA to the aqueous system. Regular H₂O₂ was also able to provide bioavailable oxygen but the system was poorly buffered with respect to oxygen release. The accessibility of plants to bioavailable oxygen was indicated by the activity of alcohol dehydrogenase (ADHase, EC 1.1.1.1), an anaerobically induced enzyme of flooded plants. The application of MgO₂ to flooded soil reduced ADHase activity in corn‐root tips by 91.3%. This application of MgO₂ presents a novel pathway to significantly (P < 5%) minimize adverse impacts of hypoxia on flooded corn seedlings. This finding may have broad implications for addressing hypoxicity problems in crop science and technology.     

固定化酵母细胞糖蜜酒精连续发酵的研究

本文报道采用海藻酸钙作载体固定酵母活细胞用于糖蜜酒精连续发酵的研究。结果表明:在发酵液中加人研制的微量 MG 稳定剂,可显著提高载体的稳定性。固定化酵母细胞可连续正常使用6个月以上。在温度30—33℃,pH4—5,糖浓度16％～19％(W/V)发酵条件下,每升固定化酵母细胞每小时可产酒精24～25g;固定化酵母细胞分批和连续发酵,分别比传统的游离酵母分批发酵效率提高24％和8倍以上。     

杨树肉桂醇脱氢酶基因序列和表达模式分析及CAD4酶活性检测

应用生物信息学方法从杨树基因组数据库中筛选出19个杨树肉桂醇脱氢酶基因,它们聚为3类.序列分析表明,杨树CAD基因家族主要通过全基因组加倍和串联复制的方式进行扩张.杨树和拟南芥CAD家族共6对旁系同源基因,在较强的净化选择压力下进化.19个基因在杨树不同组织中均有表达,表达量较高的是PoptrCAD17、PoptrCA...     

龙胆草有效成分提取方法的研究

应用四种方法－冷浸法、温度法、冷浸研磨法、索氏提取法对龙胆草中有效成分进行提取，结果表明，索氏提取得率最高，其它三种方法差异较小。     

增施CO2对温室沙培厚皮甜瓜生长发育影响的初步研究

在日光温室内燃烧酒精增施ＣＯ２气肥,能提高通风前无土栽培温室内ＣＯ２浓度,明显增强西域１号网纹甜瓜植株生长势,增产３６．６％,增值５１．４％。     

解淀粉芽胞杆菌HAB-6抑菌活性成分的分析

为明确解淀粉芽胞杆菌Bacillus amyloliquefaciens HAB-6菌株的抑菌活性物质,采用平板对峙法检测其对17种植物病原真菌的拮抗能力,通过硫酸铵沉淀法、酸沉淀法、有机溶剂萃取法提取HAB-6菌株的活性物质,并检测其稳定性。结果表明:解淀粉芽胞杆菌HAB-6菌株对17种植物病原真菌均具有良好的抑菌活性,抑制率可达45.48%~72.20%;不同提取方法中仅正丁醇粗提物有抑菌活性,在5 mg/m L浓度下抑菌圈直径达21.49 mm;正丁醇粗提物经紫外线照射120 min后,抑菌活性为对照的78%,而经100℃高温处理后抑菌活性仍为对照的91%,表明HAB-6菌株的活性物质具有较好的热稳定性;但不耐强酸强碱,其适宜的p H为5.0~9.0。正丁醇粗提物可抑制芒果炭疽病菌孢子萌发和菌丝生长,能有效抑制芒果炭疽病菌对芒果果实的侵染。表明HAB-6菌株抑菌谱广,其正丁醇提取物具较强的抑菌活性和较好的稳定性,具有良好的开发应用前景。     

西气东输二线冰堵问题与处理

针对西气东输二线管道因站场卧式过滤分离器冰堵而无法正常运行的问题,对红柳站冰堵问题进行分析,结果表明：红柳站天然气进站温度过低、烟墩一红柳站间管段高程差较大以及管道输量的增加是冰堵发生的主要原因。详细阐述了更换过滤分离器滤芯、掺混西气东输一线高温天然气和注醇、烟墩站启动压缩机增压等处理冰堵问题的方法与措施,提出了西气东输二线预防和处理冰堵的相关建议。     

酸性醇醚磷酸酯中单、双酯含量的测定

以三氯氧磷和醇醚为原料合成的醇醚磷酸酯中含有大量盐酸,盐酸的存在影响产品中单、双酯含量的确定.通过测定氯离子含量可间接确定醇醚磷酸酯中的盐酸含量,从而可较准确的测定单酯、双酯、三酯及磷酸含量.