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对文题所述方法,根据实验数据进行仿真研究,获得了满意的结果。为高度复杂的非线性生化过程的模型化提供了一条新的途径。 相似文献
3.
提出了利用上位机参与实时控制,综合分析在线参数、离线参数和间接参数,辅助发酵过程工艺研究和优化控制,并给出了上位机软件包的部分源程序及框图。该软件包对发酵工艺人员进一步了解菌种的遗传特性、细胞代谢调节和反应器工程特性方面有较大帮助。 相似文献
4.
张英霞 《科技情报开发与经济》2003,13(12):288-289
就新规范中住宅给水管管径、引入管阀门设置、水箱进水管和溢水管设置、水箱水位控制、通气管系统设计及地漏的设置等方面谈了作者学习《建筑给水排水设计规范》(GB50015-2003)的体会。 相似文献
5.
Brian H. Davison Nhuan P. Nghiem Gerald L. Richardson 《Applied biochemistry and biotechnology》2004,114(1-3):653-669
More than 25 sorbents were tested for uptake of succinic acid from aqueous solutions. The best resins were then tested for
successive loading and regeneration using hotwater. The key desired properties for an ideal sorbent are high capacity, complete
stable regenerability, and specificity for the product. The best resins have a stable capacity of about 0.06 g of succinic
acid/g of resin at moderate concentrations (1–5 g/L) of succinic acid. Several sorbents were tested more exhaustively for
uptake of succinic acid and for successive loading and regeneration using hot water. One resin, XUS 40285, has a good stable
isotherm capacity, prefers succinate over glucose, and has good capacities at both acidic and neutral pH. Succinic acid was
removed from simulated media containing salts, succinic acid, acetic acid, and sugar using a packed column of sorbent resin,
XUS 40285. The fermentation byproduct, acetate, was completely separated from succinate. A simple hot water regeneration successfully
concentrated succinate from 10 g/L (inlet) to 40–110 g/L in the effluent. If successful, this would lower separation costs
by reducing the need for chemicals for the initial purification step. Despie promising initial results of good capacity (0.06
g of succinic/g of sorbent), 70% recovery using hot water, and a recovered concentration of >100 g/L, this regeneration was
not stable over 10 cycles in the column. Alternative regeneration schemes using acid and base were examined. Two (XUS 40285
and XFS-40422) showed both good stable capacities for succinic acid over 10 cycles and >95% recovery in a batch operation
using a modified extraction procedure combining acid and hot water washes. These resins showed comparable results with actual
broth. 相似文献
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Ong LG Abd-Aziz S Noraini S Karim MI Hassan MA 《Applied biochemistry and biotechnology》2004,118(1-3):73-79
The oil palm sector is one of the major plantation industries in Malaysia. Palm kernel cake is a byproduct of extracted palm
kernel oil. Mostly palm kernel cake is wasted or is mixed with other nutrients and used as animal feed, especially for ruminant
animals. Recently, palm kernel cake has been identified as an important ingredient for the formulation of animal feed, and
it is also exported especially to Europe, South Korea, and Japan. It can barely be consumed by nonruminant (monogastric) animals
owing to the high percentages of hemicellulose and cellulose contents. Palm kernel cake must undergo suitable pretreatment
in order to decrease the percentage of hemicellulose and cellulose. One of the methods employed in this study is fermentation
with microorganisms, particularly fungi, to partially degrade the hemicellulose and cellulose content. This work focused on
the production of enzymes by Aspergillus niger and profiling using palm kernel cake as carbon source. 相似文献
9.
The effect of the trace metals Cu, K, Na, and Ca, separately or in mixture, on fermentation time, ethanol production rate,
and cell growth in the fermentation of synthetic media containing sucrose is discussed. The results are related to the range
of contents found in raw materials, molasses and raisins, in order to determine their optimum concentrations for alcohol production. 相似文献
10.
Shi Nian-Qing Prahl Kristine Hendrick Jim Cruz Jose Lu Ping Cho Jae-Yong Jones Sharon Jeffries Thomas 《Applied biochemistry and biotechnology》2000,84(1-9):201-216
Pichia stipitis CBS 6054 will grow on d-xylose, d-arabinose, and l-arabinose. d-Xylose and l-arabinose are abundant in seed hulls of maize, and their utilization is important in processing grain residues. To elucidate
the degradation pathway for l-arabinose, we obtained a mutant, FPL-MY30, that was unable to grow on d-xylose and l-arabinose but that could grow on d-arabinitol. Activity assays of oxidoreductase and pentulokinase enzymes involved in d-xylose, d-arabinose, and l-arabinose pathways indicated that FPL-MY30 is deficient in d-xylitol dehydrogenase (D-XDH), d- and l-arabinitol dehydrogenases, and d-ribitol dehydrogenase. Transforming FPL-MY30 with a gene for xylitol dehydrogenase (PsXYL2), which was cloned from CBS 6054 (Gen Bank AF127801), restored the D-XDH activity and the capacity for FPL-MY30 to grow on
l-arabinose. This suggested that FPL-MY30 is critically deficient in XYL2 and that the d-xylose and l-arabinose metabolic pathways have xylitolas a common intermediate. The capacity for FPL-MY30 to grow on d-arabinitol could proceed through d-ribulose. 相似文献