绿豆饮料添加稳定剂的响应面法优化

【目的】以绿豆为原料,添加不同的稳定剂优化绿豆饮料的稳定性。【方法】以绿豆饮料离心沉淀率为指标,在调查羧甲基纤维素钠(CMC-Na)、三聚磷酸钠(STPP)、六偏磷酸钠(SHMP)3个单体稳定剂影响绿豆饮料稳定性单因素试验结果的基础上,采用响应面分析确定最佳稳定剂配比。【结果】结果表明,当复合稳定剂CMC-Na、STPP和SHMP的添加量分别为0.02%、0.10%、0.06%时,绿豆饮料的离心沉淀率最小值为9.19%。【结论】降低沉淀率,部分解决绿豆饮料沉淀问题,为绿豆饮料生产提供参考。     

小麦高分子量谷蛋白亚基与小麦品质性状关系的研究

采用SDS-PAGE方法, 通过对4个优质亲本与3个农艺亲本间杂交获得的F2群体的每一单株及其亲本进行小麦高分子量谷蛋白亚基(HMW-GS)组成分析, 并对每一F2单株上F3籽粒群体的高分子量谷蛋白亚基组成与其籽粒蛋白质含量、 SDS-沉降值的关系进行研究,结果表明：小麦高分子量谷蛋白亚基组成不同的群体间籽粒蛋白质含量差异不显著     

Genetic mapping of sedimentation volume across environments using recombinant inbred lines of durum wheat

SDS-sedimentation volume (SV) is a biochemical index widely used to evaluate flour quality in durum and bread wheats. Significant association between SV and endosperm proteins (gliadin, high-molecular-weight- and low-molecular-weight-glutenin subunits) have been reported. Protein loci, however, account for only a portion of the total genetic variability. The objective of this study was to identify and locate quantitative trait loci (QTLs) associated with SV in a set of recombinant inbred (RI) lines, derived from a cross between the cv.‘Messapia’ of durum wheat and the accession MG4343 of the var. dicoccoides, and characterized for 259 genetic and molecular (RFLP) markers. Significant differences were detected for the quality index in the six environments examined, while the pattern of variability was that of a quantitative trait. Regression analysis of marker loci and sedimentation volume indicated, as expected, that chromosome 1B, on which are located the Gli-B 1/Glu-B 3 loci for some gliadin and glutenin subunits, is important for wheat quality. Two additional regions located on chromosomes 6AL and 7BS, and four regions on 1AL, 3AS, 3BL and 5AL, were shown to have single-factor effects on sedimentation volume at P < 0.001 and P < 0.01, respectively. Positive effects were contributed by both parents. A multiple linear regression model consisting of seven significant loci on different chromosomes explained 62–91% of the genotypic variation of the trait. The availability of linked markers to QTLs may facilitate the genetic dissection of quantitative traits and the early selection in wheat breeding programmes.     

Water Conservation Forest Impacts on the Runoff Generation and Sedimentation at the Natural Slope Scale in the Miyun Reservoir Watershed

在考虑地表流边界条件情况下,森林对降雨径流和泥沙的影响是一个非常复杂的过程．本文给出了水源保护林在自然坡面尺度上对径流泥沙影响的初步试验研究结果,森林在自然坡面尺度上对１９９７年７月３１日至８月１日降雨过程的洪峰流量消减率达４５５９％,洪水总量的消减率为６．８％,森林坡面径流总量为９８０．７８ｍ３,荒草坡为１０５２２３ｍ３．森林对１９９６年７月３０日降雨过程的洪峰流量消减率为１７．９５％,森林坡面的径流总量为１５．０８ｍ３,荒草坡为１８．３８ｍ３．从１９９６年森林对降雨径流较低的消减率看,降雨量与降雨强度对径流泥沙有很大的影响．     

木材厂环境中空气微生物的初步研究

本文采用自然沉降平板法,对哈尔滨市某木材厂空气微生物种类和数量进行测定.结果表明:未经空气净化器处理的木材生产车间中的空气微生物数量(54939 cfu(m-3)是经空气净化器处理(25768 cfu(m-3)的2.1倍.空气净化器虽然能够净化生产车间中的空气微生物,但其净化率为53.1%,净化后的空气未达到洁净空气的标准,因此还应同时采取其他相应净化措施.净化器可以显著降低空气中放线菌的数量,尤其能够完全清除放线菌,如:疮痂类群(Scabies), 烬灰类群(Cinereas)和吸水类群(Hygroscopicas),但对细菌和真菌效果不明显.建议今后采用更有效可行的方法来净化木材生产车间中的空气微生物.     

Bacterial community composition shifts in sediments influenced by fish feeds

This study investigated the influence of fish feed deposition on the microbial community of sediments in a coastal lake. Microcosms were designed to simulate the addition of fish feeds to the sediment, and physicochemical factors as well as composition of microbial assemblages were analysed. Although total organic carbon and total organic nitrogen did not significantly increase, redox potential and total sulphides showed a transition of sediment environments into anaerobic condition due to the addition of fish feeds. The bacterial community composition shifted with fish feed deposition as revealed by the band profiles of denaturing gradient gel electrophoresis, Sørensen's similarity indices and cell numbers of sulphate‐reducing bacteria. Occurrence of anaerobic bacteria (sulphate and nitrate reducers) and disappearance of strictly aerobic bacteria were observed with fish feed inputs. The results clarify the succession of the microbial flora and suggest negative impact of uneaten fish feeds on the microbial community in sediment and resultant environmental deterioration of fish‐farming areas.     

Artificial reefs as a reef restoration strategy in sediment‐affected environments: Insights from long‐term monitoring

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沉积作用及应力历史对自重应力和沉降的影响

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