外循环流化床生物反应器的特性及应用

针对固定化增殖细胞发酵酒精的特点,研制与开发了一种新型外循环流化床生物反应器和大规模制备固定化细胞颗粒的方法和装置。考查了固定化细胞颗粒流化特性,外循环速度对液相停留时间分布的影响,宏观发酵动力学及固定化增殖细胞发酵酒精的特点及历程。设计并完成了665L 中试规模的放大试验,连续运转近3个月。实验结果表明:以未处理无灭菌的废甘蔗糖蜜为原料,用海藻酸钙包埋的固定化酵母颗粒连续发酵酒精,终酒精浓度为8～10%(v/v),对糖收率>92%,反应器生产能力达12kg/(m~3·h)

外循环流化床生物反应器的流动及发酵特性——固定化增殖酵母连续发酵生产酒精

为解决固定化增殖酵母发酵生产酒精过程中生成的 CO_2气体附着在酵母载体表面,影响传质及生物反应速率,导致发酵过程操作条件恶化等问题,并针对发酵过程反应速度慢、要求液相停留时间长的特点,在外循环准三相流化床生物反应器发酵生产酒精过程中考察了固定化增殖酵母颗粒的特性、流化床生物反应器的流动特性及液相混合,提出了经修正的液相混合模型.在此基础上,对外循环流化床生物反应器应用于固定化酵母颗粒增殖和发酵生产酒精的过程进行了研究

Studies on Transgenic Rice with Heat-shock Inducible Expression of Hd3a Gene

Hd3A(HEAdIng dATE 3A)基因是光周期诱导水稻开花过程中的一个关键调控基因,它在短日条件下表达并促进水稻开花.通过根癌农杆菌介导的方法将热激诱导表达的Hd3A基因转化到水稻品种日本晴中.热激处理转基因植株后,检测结果表明,叶片中转基因Hd3A的表达水平比热激前显著提高,随后又下降到热激前的水平,说明转基因Hd3A在水稻中可以被热激诱导瞬间的表达.长日条件下热激转基因水稻可成功诱导其抽穗,而同样处理的野生型植株不能抽穗,表明Hd3A的瞬间表达可诱导水稻开花,且其开花的早晚与热激处理的强度有关.Hd3a(Heading date 3a)plays a key regulatory role in the photoperiod flowering pathway of rice(Oryza sativa).In this study,a heat-shock inducible Hd3a gene was transformed into wild-type rice mediated by Agrobacterium tumifaciens.The result of real-time PCR analysis showed that the expression level of transgene Hd3a increased significantly after heating treatment,and soon decreased to the background level,which suggested that Hd3a expression can be induced transiently to a very high level.In the long-day condition,the flowering of transgenic rice can be induced by heating treatment,while wild type plants can not flower with the same treatment.It proved that a transient expression of Hd3a could induce transgenic rice to flower.There was a positive correlation between flowering time and heating treatment times.福建省青年人才项目(2006F3123);霍英东教育基金(111026)资

中试规模外循环流化床反应器生产酒精

<正> 利用固定化酵母技术实现快速发酵,是当今酒精生产工艺的重大突破。"七五"期间,中科院化冶所与沈阳应用生态所,经过大量的小试研究工作,确定了适合糖蜜发酵生产酒精的优良菌种和适宜的发酵工艺条件,利用自己研制的大规模固定化酵母颗粒制备装置及相应的外循环流化床生物反应器,进行了近三个月的中间扩大试验。本文简报这一研究结果

新疆西天山松湖铁矿床地质特征及成因探讨[J]

松湖铁矿床位于新疆西天山阿吾拉勒成矿带中段,伊犁石炭-二叠纪裂谷内。矿区地层整体为一套单斜构造,主要出露下石炭统大哈拉军山组第二岩性段(C1d2),为一套海相火山碎屑岩-碳酸盐岩组合,主要岩性包括凝灰岩、晶屑岩屑凝灰岩及凝灰质粉砂岩等,局部夹少量透镜状灰岩及碳质凝灰岩。矿区内断裂及节理构造发育,其中F3逆断层沿北西西向延伸,是区内主要的

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies