含氮聚氯乙烯-吡啶树脂对β-萘酚及有机酸性物质的吸附和脱附性能

以含氮聚氯乙烯-吡啶树脂作吸附剂,研究它对β-萘酚的静态吸附和脱附情况,以及温度对树脂吸附性能的影响。结果表明,含氮聚氯乙烯-吡啶树脂对β-萘酚有良好的吸附性和脱附性,在相同温度下,其吸附量和脱附率分别为1.32mmol/g和91%;树脂对β-萘酚的吸附量随着温度的升高而降低,吸附过程是一个放热过程。含氮聚氯乙烯-吡啶树脂对有机酸性物质有明显的吸附性能,虽然规律不很强,但是与酸性强弱有关,酸性明显强者(如甲酸、不饱和酸、取代酸),其吸附量较大,β-萘酚的酸性较弱,其吸附量较小。

好氧优势菌株分离及其对垃圾渗滤液中有机酸性物质的降解研究

分离筛选能够快速降解垃圾渗滤液中难降解有机酸性物质的优势菌种8株,研究了这8菌株及其混合体对苯甲酸、苯酚、邻苯二甲酸、脂肪酸等以垃圾渗滤液中常见的有机酸性物质的降解特性。这8株高效单一菌株中3株为细菌,2株为真菌,3株为放线菌。研究结果表明,8菌株对有机酸性物质的降解效果均有不同,不同菌株对不同有机酸性物质有最佳的降解效果,在特定的条件下可降解至最低甚至到零。混合菌群对芳香有机酸性混合物的降解效果最好,反应48h内芳香类酸性物质产生的COD去除率为74.7%。

Effects of Bagging with Paper Bags and Non-woven Bags on Flavor Compounds of Feicheng Peach

With Hongli Feicheng Peach as the test material, the effects of bagging with 4 kinds of paper bags and 3 kinds of non-woven bags on the soluble sugar, organic acids and aroma compounds in peach fruits were investigated using headspace solid-phase microextraction （HS-SPME） combined with gas chromatogra- phy-mass spectrometry （GC-MS） and high-performance liquid chromatography （HPLC）. The results showed that there were significant differences in sugar and acids contents of peach fruits between different bagging treatments. The sugar con- tent of peach fruits was increased when bagged with single-layer inner-black outer- yellow paper bags and double-layer inner-white outer-yellow paper bags. The organ- ic acid content in peach fruits bagged with all the types of bags except the single- layer inner-black outer-yellow paper bag was increased greatly. The count and rela- tive content of aroma compounds were all decreased after bagging. Combined with the detection results of soluble sugar, organic acids and aroma compounds, the sin- gle-layer inner-black outer-yellow paper bag was suitable for bagging of Hongli Fe- icheng peach.

Intake and Digestibility of Native and Exotic Grasses Fed Ad libitum to Djallonke Sheep in South Benin

Native （Andropogon gayanus, Panicum maximum and Pennisetum purpureum） and exotic grasses （Brachiaria ruzi：iensis, Panieum maximum cv. C1 and T58） consumed in tropical humid zone were evaluated by estimating their voluntary intake and in vivo digestibility. The measurements were performed with 4 male Djallonke sheep （28 kg LW） fed ad libitum in metabolic cages, during a 10-days in vivo trial, preceded by a 14-days accommodation period. Each grass was studied at 3 stages of development. The samples （distributed grasses, refusals and faeces） were analysed for organic matter （OM）, crude fibre （CF）, neutral detergent fibre （NDF）, acid detergent fibre （ADF）, acid detergent lignin （ADL） and crude protein （CP） contents. Voluntary digestible organic matter intake （VDOMI） and voluntary digestible crude protein intake （VDCPI） were calculated （in g kg ^-1 LW075） as synthetic parameters to compare the grasses. The chemical composition of the distributed forages varied significantly （P 〈 0.001） between species or cultivars and development stages. After 4-5 leaves per tiller stage, CP contents decreased in all species and lowest in native species. Andropogon gayanus was the most l ignified species at any stage of development. At the end of the rainy season, Pennisetum purpureum leaves and Brachiaria ruziziensis had the highest CP. For all the grasses, CP contents were higher （and CF contents lower） in the consumed material, compared to the offered forages, showing thereby the high selectivity by the sheep. Dry matter intake, OM and CP digestibility varied greatly （P 〈 0.001） between forages and development stages with high interactions between these factors （P 〈 0.001）. Voluntary digestible organic matter intake and VDCPI were the highest （P 〈 0.05） for native Panicum maximum and Pennisetum purpureum. There was a relationship between digestibility and intake parameters, and ADL content of the grasses seems to be an important factor determining at least digestibility.

蓝莓土壤pH值调控技术研究进展

土壤pH值是限制蓝莓栽培的重要因素。近年来,蓝莓栽培土壤pH值调控技术研究取得了较大进展。本文主要对通过添加无机元素或无机化合物、添加或覆盖酸性有机物质、施用酸性化学肥料以及施用生物菌肥或接种菌根真菌来降低土壤pH值的技术及机理进行了综述。对今后蓝莓栽培土壤pH值调控技术研究作出了展望。