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Solid-phase extraction method was developed for the preconcentration of thorium (Th). Fungal biomass Agaricus bisporus was immobilized to Amberlite XAD-4 as solid-phase sorbent. The critical parameters such as pH of the sample solution, flow rate of the sample, volume of the sample, and the effect of major ions that affect the preconcentration of thorium in this system were evaluated. The optimum pH for the sorption of Th is 6.0, and quantitative elution occurs with 1.0 mol L?1HCl. The loading capacity was determined as 0.079 mmol g?1. The optimized method was validated through analysis of the certified reference material of tea leaves (NCS ZC73014) and successfully applied to the determination of Th in a real ore sample with satisfactory results.  相似文献   
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Changes in the chemical composition of isolated cell walls and fractions were encountered during the differentiation of vegetative and aggregated mycelia of Agaricus bisporus.Differentiation was accompanied by quantitative variations of the wall polysaccharidic components. Neutral carbohydrates were composed of glucose, galactose, mannose and xylose and glucosamine as the only amino sugar. Differences in wall chemistry were correlated to the secondary and tertiary mycelial forms.  相似文献   
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A simple, but effective on-line method for estimating the mycelial cell mass concentration from agitation speed data, a most readily-available process variable, has been developed for DO-stat cultures ofAgaricus blazei. The dynamic change of dissolved oxygen concentration (DOC) in the initial transient period and the change in yield were considered in the development of the estimation algorithm or estimator. Parameters in the estimation algorithm were calculated from the agitation speed data at 20% of DOC. The proposed estimator could accurately predict the cell mass concentration regardless of DOC levels in the tested range of 10–40%, showing a good extrapolation capability.  相似文献   
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Die herbizide Wirksamkeit von Bromoxynil und Phenmedipham wird in starkem Maße von der Lösungsmittelkomponente der Herbizidformulierung beeinflußt. Es zeigt sich, daß die Photosynthesehemmung — als Maß für die Herbizidwirkung — mit zunehmender Hydrophilie der verwendeten Lösungsmittel sinkt, was insbesondere anhand der untersuchten Essigsäurealkylesterreihe nachweisbar ist. Zwischen der Wirkstoffapplikation auf Ganzblättern und isolierten Chloroplasten treten beträchtliche Wirkungsunterschiede auf. Demnach ist der wirkungsbegrenzende Schritt nicht innerhalb der Thylakoidmembran selbst zu suchen sondern findet auf dem Wege von der Blattoberfläche zum Chloroplasten statt.  相似文献   
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We studied the appearance of fruit body primordia, the growth of individual fruit bodies and the development of the consecutive flushes of the crop. Relative growth, measured as cap expansion, was not constant. It started extremely rapidly, and slowed down to an exponential rate with diameter doubling of 1.7 d until fruit bodies showed maturation by veil breaking. Initially many outgrowing primordia were arrested, indicating nutritional competition. After reaching 10 mm diameter, no growth arrest occurred; all growing individuals, whether relatively large or small, showed an exponential increase of both cap diameter and biomass, until veil breaking. Biomass doubled in 0.8 d. Exponential growth indicates the absence of competition. Apparently there exist differential nutritional requirements for early growth and for later, continuing growth. Flushing was studied applying different picking sizes. An ordinary flushing pattern occurred at an immature picking size of 8 mm diameter (picking mushrooms once a day with a diameter above 8 mm). The smallest picking size yielded the highest number of mushrooms picked, confirming the competition and arrested growth of outgrowing primordia: competition seems less if outgrowing primordia are removed early. The flush duration (i.e. between the first and last picking moments) was not affected by picking size. At small picking size, the subsequent flushes were not fully separated in time but overlapped. Within 2 d after picking the first individuals of the first flush, primordia for the second flush started outgrowth. Our work supports the view that the acquisition of nutrients by the mycelium is demand rather than supply driven. For formation and early outgrowth of primordia, indications were found for an alternation of local and global control, at least in the casing layer. All these data combined, we postulate that flushing is the consequence of the depletion of some unknown specific nutrition required by outgrowing primordia.  相似文献   
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为探讨巴氏蘑菇子实体不同发育阶段基因的表达情况,本研究对巴氏蘑菇子实体不同发育时期(原基、采收期和开伞期)进行转录组测序,以本实验室已获得的巴氏蘑菇JA菌株的不育单孢菌株JA-15036基因组为参考基因组研究原基与采收期及开伞期样本间差异表达基因,并对差异表达基因进行了GO功能和Pathway富集分析。GO功能分析结果显示,差异表达基因主要富集在跨膜转运、碳水化合物代谢途径和膜组分,它们协同调控为子实体生长发育提供稳定的内环境。KEGG富集分析结果表明,原基期上调的差异表达基因主要富集在核糖体蛋白和DNA复制,表明原基期细胞代谢旺盛,其中核糖体蛋白基因上调为后期蛋白质合成提供重要场所;采收期和开伞期子实体时期差异表达基因主要富集在碳水化合物代谢、脂肪酸降解和氨基酸代谢等途径,为巴氏蘑菇子实体的生长发育与成熟提供营养与能量。  相似文献   
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