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In order to investigate the composition of borage (Borago officinalis L.) seed oil, this research was performed under the field conditions at Shahriyar and Garmsar zones, Iran during the 2012 planting year. The oil yield of borage was 31.46% and 33.7% at Shahriyar and Garmsar zone, respectively, and nine and eight fatty acids were identified in the seed oil of borage at Shahriyar and Garmsar, respectively – palmitic, linoleic, stearic and γ-linolenic acids were dominant in the seed oil of borage from both zones. Unsaturated fatty acid content was more than the saturated fatty acids in both zones. The ratio of linoleic acid and α-linolenic acid in the borage cultivated at Shahriyar and Garmsar zones was 2.13 and 2.29. The fatty acid profile of Garmsar borage, oleic and oleic/linoleic acid ratio, increased. Locations with different ecological conditions resulted in changes in both seed oil content and fatty acid profile of borage.  相似文献   
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基于遗传算法的改进GLA算法   总被引:1,自引:0,他引:1  
提出了基于遗传算法的改进广义Lloyd算法(GLA)。它以种群为基础,使用选择算子对种群进行有针对性的操作,通过变异算子以提高种群的平均适应值,使其逃离局部最小点,最后采用交叉算子以增加个体的多样性,又降低了该算法对初始码书的敏感程度。高斯-马尔科夫序列实验表明,该算法较好地实现了全局最优,并有助于克服对初始码书较为敏感的缺点。  相似文献   
3.
Nowadays, time-resolved spectroscopy data can be routinely and accurately collected in UV-vis femtosecond transient absorption spectroscopy. However, the data analysis strategy and the postulation of a physically valid model for this kind of measurements may be tackled with many different approaches ranging from pure soft-modeling (model-free) to hard-modeling, where the elaboration of a parametric spectro-temporal model may be required. This paper reviews methods that are used in practice for the analysis of femtosecond transient absorption spectroscopy data. Model-based methods, common in photochemistry, are revisited, and soft-modeling methods, which originate from the chemometrics field and that recently disseminated in the photo(bio)chemistry literature, are presented. These soft-modeling methods are designed to suit the intrinsic nature of the multivariate (or multi-way) measurement. Soft-modeling tools do not require a priori physical or mechanistic models to provide a decomposition of the data on the time and wavelength dimensions, the only requirement being that these two (or more) dimensions are separable. Additionally, Bayesian data analysis, which provides a probabilistic framework for data analysis, is considered in detail, since it allows uncertainty quantification and validation of the model selection step.  相似文献   
4.
To study the effect of agitation speed (rpm) and dissolved oxygen concentration (DO) on the production of gamma linolenic acid by Mucor sp. RRL001, a central composite design experiment was performed in a 5-L stirred tank bioreactor. The design consisted of a total of 10 runs consisting of runs at five levels for each factor and was divided in two blocks. The ANOVA analysis and Pareto chart of effects suggested agitation speed (p = 0.0142) linear effect and DO concentration (p = 0.0342) quadratic effects were significant factors with significant contribution to the response. The validation run based on the optimum production zone in response surface plot resulted in the maximum 350.3 mg l−1 GLA yield as compared with model predicted value of 340.7 mg l−1. The study suggests that agitation rate is having more pronounced effect on GLA yield than dissolved oxygen concentration by ensuring enhanced mass transfer and by preventing wall growth at elevated agitation speed. Also, it shows that higher GLA yields can be obtained in a simple medium at moderate oxygen saturation and that the Mucor sp. RRL001 is resistant to high agitation linked shear stress and suitable for GLA production at higher scale.  相似文献   
5.
He-Ne激光对γ-亚麻酸产生菌少根根霉的诱变作用   总被引:10,自引:3,他引:7  
采用He-Ne激光和化学诱变剂LiCl对少根根霉孢子和原生质体进行复合诱变,从一株产GLA的出发菌株少根根霉R8#中选育出高产菌株RC378.摇瓶培养含油脂量47.8%,GLA含量12.6%,比出发菌株油脂含量提高了130.8%,GLA含量提高了276.7%.从菌落形态、同工酶酶谱、红外光谱吸收特征和油脂产量及组成比较分析表明:该菌株较出发菌株具有显著的变异.菌株RC378经传代培养,产脂量维持在41.1%~48.7%,GLA含量维持在10.8~12.6%.该菌株具有较好的遗传稳定性.  相似文献   
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研究GLA算法和随机松驰算法设计的线谱对码本性能以及两种算法的特点,训练数据采用了云均值和一阶滑动平均模型预测的误差信号,随机松驰算法选用简化的解码器扰动算法,传统观点认为随机松驰算法比GLA算法每适量索引少用1bit.实验结果表明,在小训练数据量时的确如此,但在大数据量时它们的性能相差不大。在线谱对的码本设计中,随机松驰算法设计的码本信噪比提高很小。  相似文献   
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