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1.
以衡阳师范学院近两届毕业生实习调查报告的评优数据为研究对象,分析了衡阳师院实习调查环节的落实现状,并探究其原因,有针对性地提出了一些具体措施,以供其它新办本科院校参考.表4,参6.  相似文献   

2.
高职特色的《园林昆虫学》教学改革尝试   总被引:1,自引:0,他引:1  
高职特色的《园林昆虫学》教学改革,应主动适应经济社会的发展需要,突出实用性和针对性,加强实践能力培养,贯彻产学结合思想,从实际出发,办出特色.在遵循上述原则的基础上,调整教学课时的分配比例,联系生产单位实训,改革教学内容,改革教学方法,改革教学评估体系.  相似文献   

3.
固固共混法制备聚合氯化铝混凝剂   总被引:3,自引:2,他引:1  
采用固固共混法,制备具有不同铝浓度和碱化度(B)的聚合氯化铝(PAC)混凝剂.实验结果表明,在高铝浓度下可制备出较高含量Alb的PAC,制备条件对PAC中Alb的含量影响很大.B值的升高可以提高PAC中Alb的含量,但铝浓度的提高和熟化时间的延长则会降低产品中Alb的含量.反应温度为80℃左右时可制备出高Alb含量的PAC.加药时间和熟化时间对制备的影响不大.  相似文献   

4.
多糖产生菌T与β-胡萝卜素产生菌C1-B的融合研究   总被引:3,自引:0,他引:3  
以多糖产生菌T和胡萝卜素产生菌C1-B为双亲,用原生质体融合技术选育出了1株既产多糖又产胡萝卜素的杂交品系,在对这两株菌的原生质体形成、再生的研究基础上,以PEG6000加新生磷酸钙为助融剂,对其进行了原生质体的融合,融合率达3.48×10-7,并选择出了遗传性能稳定的融合子F.该融合子具有双亲优势,得到的发酵液多糖和β胡萝卜素产量分别达8.7g/L和13.7mg/L.  相似文献   

5.
以三油酸甘油酯-醋酸纤维素复合膜(TECAM)萃取作为监测水体中痕量有机氯农药的方法.探讨分析过程中的影响因素和优化条件,结果表明,膜萃取分析方法对17种有机氯农药的平均加标回收率为53%-111%,对强疏水性污染物表现出较高的回收率.利用该方法在南方某自来水厂各工艺段水体中检测出了滴滴涕及其代谢产物、六六六等五种有机氯农药.  相似文献   

6.
有机磷农药降解菌的紫外诱变育种   总被引:20,自引:0,他引:20  
有机磷农药降解菌地衣芽孢杆菌( Bacilluslicheniformis) 经紫外线诱变后,筛选出突变菌株P12 .在θ=30℃,溶解氧ρ(O2) =2 .5 mg L-1 的培养条件下,3 d 内对甲胺磷的降解率为80 .1% ,比出发菌株提高了将近10%的降解率.农药斜面连续传代10 次,降解活力保持稳定.  相似文献   

7.
从市售蔬菜乳酸发酵产品中分离、筛选出一组菜籽饼高效脱毒菌株:酵母菌 Y12 和乳酸杆菌 L3141 .经过正交试验选择出该两分离株混合发酵菜籽饼脱毒的最佳条件,以此建立了限定性固体混合发酵菜籽饼脱毒的工艺.结果表明:在加水量 w = 80 % ,加糖量 w = 1 % ,自然p H 值和30 ℃条件下,接种( w)10 % 液体菌种( Y12 : L3141 = 0 .5 :1) 厌气发酵4 d ,菜籽饼硫葡萄糖苷脱毒率可达91 .30 % 以上.经过化验分析,脱毒后菜籽饼粗蛋白质和氨基酸总含量分别比 C K 提高3 .9 % 和5 .6 % .小白鼠急性毒性试验表明小白鼠无中毒症状反应  相似文献   

8.
在紫色砂岩发育的严重侵蚀红壤上,开展尾叶桉施肥试验。结果表明,NPK复合肥的施用,明显地促进了尾叶桉的生长,但在未加人微量元素肥料的情况下,表现出明显的微量元素缺乏病症,致使尾叶桉分生组织畸变,上部枝条折断,成丛生状,顶端优势不明显。20个月生时,NPK+微肥处理的树高和胸径,与NPK处理的相比较,分别提高54.3%和104.9%,是对照无肥处理的3.64倍和1.58倍,表现出极显著的微量元素施肥效果。  相似文献   

9.
高职《企业经营管理》课程教学与考试考核方法初探   总被引:2,自引:0,他引:2  
根据《企业经营管理》教学经验,初步总结出《企业经营管理》课程教学与考试考核方法.认为《企业经营管理》教学应该采取灵活多样的教学方法和科学合理的考试考核方法,以达到培养集创新型、应用型和技能型于一体的企业经营管理一线的合格人才的目标.参4.  相似文献   

10.
有机废水厌氧酸化和聚羟基烷酸生产组合系统的研究   总被引:6,自引:0,他引:6  
以30g/L葡萄糖合成废水为原料,研究了厌氧酸化的操作温度(θ)对酸化率的影响,确定了达到最佳酸化产物分布时的pH值,并以酸化反应器的出水为碳源,在5L发酵罐上进行了分批和流加发酵实验.结果表明,θ=40℃时,废水的酸化率接近100%;控制pH5.7,停留时间10h可使丁酸占UASB反应器出水中总酸质量的68%;与分批发酵相比,流加发酵法可大幅度地提高PHA的产量,发酵54h后,DCW和PHA的质量浓度可分别达到15.8g/L和10g/L.  相似文献   

11.
On the behaviour of the residence time at the bottom of the mixed layer   总被引:1,自引:0,他引:1  
To understand why the findings of Deleersnijder et al. [(2006), Environ Fluid Mech 6: 25–42]—the residence time in the mixed layer in not necessarily zero at the pycnocline—are consistent with those of Delhez and Deleersnijder [(2006), Ocean Dyn 56:139–150]—the residence time in a control domain vanishes at the open boundaries of this control domain—, it is necessary to consider a control domain that includes part of the pycnocline, in which the eddy diffusivity is assumed to be zero. Then, depending on the behaviour of the eddy diffusivity near the bottom of the mixed layer, the residence time may be seen to exhibit a discontinuity at the interface between the mixed layer and the pycnocline. If such a discontinuity exists, the residence time is non-zero in the former and zero in the latter. This is illustrated by analytical solutions obtained under the assumption that the eddy diffusivity is constant in the mixed layer.  相似文献   

12.
知识经济时代,企业最宝贵的财富是知识型员工。知识型员工是生产力的代表。知识型员工的工作效率决定了企业的竞争能力.因此。如何激励知识型员工成为企业探讨的一个重要问题.本文从知识型员工的特点入手。按有关知识管理专家提出的激励因素,从四个方面阐述了对知识型员工的激励策略。并提出了对知识型员工的管理对策.  相似文献   

13.
14.
豪猪消化系统的解剖研究   总被引:3,自引:0,他引:3  
为了了解豪猪的消化生理,为豪猪的人工饲养技术研究提供基础依据,以达到高效饲养豪猪的目的,笔者对豪猪的消化器官进行了系统解剖研究.结果表明:豪猪的胃为单室胃.盲肠很发达,这与其能够消化植物纤维有关.豪猪肝脏很发达,其重量为402 g,是其体重的4.59%,肝脏分叶多而明显.  相似文献   

15.
Our research indicates that, due to the depletion of conventional, and hence cheap, crude oil supplies (i.e. peak oil), increasing the supply of oil in the future would require exploiting lower quality resources (i.e. expensive), and thus will most likely occur only at high prices. This situation creates a system of feedbacks where economic growth, which requires more oil, would require high oil prices that will undermine that economic growth. We conclude that the economic growth of the past 40 years is unlikely to continue unless there is some remarkable change in how we manage our economy.  相似文献   

16.
17.
Animals disperse in space through different movement behaviors, resulting in different displacement distances. This is often described with a displacement kernel where the long-distance dispersers are within the tail of the kernel. A displacement with a large proportion of long-distance dispersers may have impact on different aspects of spatial ecology such as invasion speed, population persistence, and distribution. It is, however, unclear whether the kurtosis of the kernel plays a major role since a fatter tail also influences the variance of the kernel. We modeled displacement in landscapes with different amounts and configurations of habitats and handled kurtosis and variance separately to study how these affected population distribution and transition time. We conclude that kurtosis is not important for any of these aspects of spatial ecology. The variance of the kernel, on the other hand, was of great importance to both population distribution and transition time. We argue that separating variance and kurtosis can cast new light on the way in which long-distance dispersers are important in ecological processes. Consequences for empirical studies are discussed.  相似文献   

18.
19.
Very high resolution imagery from an airborne multi-spectrål scanner has been used to estimate the distribution of different salt-marsh communities along a 30-km stretch of the North Norfolk coast. Field observations have been used to develop a mathematical relationship between the vegetation, physical environment and sediment accumulation. This relationship has been used to produce provisional sediment accretion maps for the north Norfolk coast.  相似文献   

20.
The use during settlement of secretions of the 9 different types of gland in the foot of the pediveliger of Ostrea edulis L. was examined experimentally. During settlement, there is a progressive decrease in the crawling speed of the larva and a strengthening of its bond with the substratum. Both changes are related to (a) a change from ciliary to muscular pedal locomotion; (b) the increasing acidity and viscosity of the mucoid secretions used; (c) the secretion of a byssus thread by the glands of the byssus duet; (d) changes in the form and composition of this byssus. At the termination of settlement, the entire contents of 2 types of gland are discharged. Their secretions give rise to the cement which permanently fixes the larva to the substratum. The 9 types of gland are utilised sequentially in a manner closely related to the 6 phases recognised in settlement behaviour.  相似文献   

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