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1.
为提高毕赤酵母重组菌产伏马毒素B1(fumonisin B1,FB1)羧酸酯酶的摇瓶发酵水平,以酶活力为指标,对发酵条件和培养基进行优化。通过单因素试验对发酵条件进行优化。通过Plackett-Burman试验筛选出关键培养基成分,再进行正交试验建立试验数据样本,最后建立误差反向传播神经网络模型进行预测并寻找最优发酵培养基组成。经优化得到的发酵条件:诱导温度28℃,初始p H 6.0,每24 h补加体积分数为1%的甲醇,诱导96 h;优化后发酵培养基组成:蛋白胨23 g/L、KH2PO444 g/L、PTM4 (Pichia trace minerals 4)微量元素溶液1.5 m L/L、K2SO47.15 g/L、Mg SO4·7H2O 5.85 g/L和酵母粉5 g/L。FB1羧酸酯酶酶活力达到402 U/m L以上,较优化前提高了1.19倍。优化后显著提高了重组菌株的产酶能力,研究结果为FB1羧酸酯酶发酵罐优化提供了基础数据。  相似文献   
2.
N—酰基肌氨酸钠的制备,性能及应用   总被引:1,自引:0,他引:1  
许虎君  连莹 《辽宁化工》1997,26(2):60-63
本文综述了N-酰基肌氨酸钠阴离子表面活性剂的制备方法和产品性能及其在化妆品,个人卫生用品和其它工业部门中的应用。  相似文献   
3.
Over the last decades, expression classification and face recognition have received substantial attention in computer vision and pattern recognition with more recent efforts focusing on understanding and modelling expression variations. In this paper, we present an expression classification and expression-invariant face recognition method by synthesising photorealistic expression manifolds to expand the gallery set. By means of synthesising expression images from neutral faces, more within-subject variability can be obtained. Eigentransformation is utilised to generate both shape and expression details for novel subjects. Expression classification and face recognition are then performed on the extended training set with synthesised expressions. Experimental results on various datasets show that the proposed method is robust for recognising various expressions and faces with varying degrees of expression. Comprehensive experiments conducted and comparisons with the existing methods are reported. Cross-database synthesis and effect of landmark quality are also studied.  相似文献   
4.
    
In this paper, we present a new shader smoothing method to improve the quality and generality of band-limiting shader programs. Previous work [YB18] treats intermediate values in the program as random variables, and utilizes mean and variance statistics to smooth shader programs. In this work, we extend such a band-limiting framework by exploring the observation that one intermediate value in the program is usually computed by a complex composition of functions, where the domain and range of composited functions heavily impact the statistics of smoothed programs. Accordingly, we propose three new shader smoothing rules for specific composition of functions by considering the domain and range, enabling better mean and variance statistics of approximations. Aside from continuous functions, the texture, such as color texture or normal map, is treated as a discrete function with limited domain and range, thereby can be processed similarly in the newly proposed framework. Experiments show that compared with previous work, our method is capable of generating better smoothness of shader programs as well as handling a broader set of shader programs.  相似文献   
5.
针对围圆冲压成形中易发生卡箍折裂的现象,使用SolidWorks建模,利用ABAQUS进行仿真运算,分析不同冲压速度下,卡箍箍带弯曲成形后的应力、应变、厚度的分布情况.结果表明:在不同冲压速度下,卡箍箍带的应力、应变以及厚度的变化趋势大致相同,均在耳圆部分和最底部出现拉应力增大、应变集中以及厚度减小的现象,表明在此3处...  相似文献   
6.
This paper presents a fast and stable technique for simulating deformable objects. Unlike in previous physically based methods, our potential energy of deformation is purely geometrically based. It is defined as the L 2 norm of the change of the differential coordinates. A key feature of this energy formulation is that the corresponding stiffness matrix is approximately constant, which enables fast and stable implicit integration and large deformations. Our algorithm can simulate various effects including solid, thin shell and plasticity. We also adopt two schemes to accelerate the simulation process: dimensionality reduction in frequency domain and adaptive rotation computation in spatial domain.  相似文献   
7.
勾画式泊松网格编辑   总被引:1,自引:0,他引:1  
结合勾画式自由变形方法简单直观易用的优点和基于微分方程的网格变形方法能够保持形变物体几何细节的性质,提出一种勾画式的泊松网格编辑方法.通过允许目标勾画线和参照勾画线不必位于相同的相机平面,把原有的二维勾画变形推广至三维,并提出了一组完整的变形操作.这些变形操作根据参照勾画线与目标勾画线决定了一系列的局部变换,并由这些局部变换产生出用户希望的梯度场,最终根据用户需要的梯度场重建出变形后的三维模型.丰富的编辑实例表明了该方法具有直观便捷的交互特点.  相似文献   
8.
Establishing corresponding features on two non-rigidly deformed 3D surfaces is a challenging and well-studied problem in computer graphics. Unlike previous approaches that constrain the matching between feature pairs using isometry-invariant distance metrics, we constrain the matching using a discrete connectivity graph derived from the Morse–Smale complex of the Auto Diffusion Function. We observed that the graph remains stable even for surfaces differing by topology or by significant deformation. This algorithm is simple to implement and efficient to run. When tested on a range of examples, our algorithm produces comparable results with state-of-art methods on surfaces with strong isometry but with greatly improved efficiency, and often gets better correspondences on surfaces with larger shape variances.  相似文献   
9.
We synthesize and animate general texture patterns over arbitrary 3D mesh surfaces. The animation is controlled by flow fields over the target mesh, and the texture can be arbitrary user input as long it satisfies the Markov-Random-Field assumptions. We achieve this by extending the texture optimization framework over 3D mesh surfaces. We propose an efficient discrete solver inspired by k-coherence search, allowing interactive flow texture animation while avoiding the blurry blending problem for the least square solver in previous work. Our technique has potential applications ranging from simulation, visualization, and special effects.  相似文献   
10.
紧跟智能建筑的发展趋势,结合社会专业人才需求,以遵从"OBE-CDIO"相融合的工程教育理念、创建"理、实、虚"相结合教学模式、实施"CQI"工程教育质量闭环控制为特色,对建筑环境与能源应用工程专业的教学课程体系、教学内容、教学方式及教学质量方面进行改革,为高校培养适应社会需求的应用型人才提供参考。  相似文献   
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