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1.
Evaluation of the effect of processing on cocoa polyphenols: antiradical activity,anthocyanins and procyanidins profiling from raw beans to chocolate 下载免费PDF全文
Matteo Bordiga Monica Locatelli Fabiano Travaglia Jean Daniel Coïsson Giuseppe Mazza Marco Arlorio 《International Journal of Food Science & Technology》2015,50(3):840-848
The content and composition of anthocyanins and procyanidins in fermented cocoa beans (from different geographic origins: Ecuador, Cameroon, Ivory Coast, Ghana and Nigeria), roasted nibs, cocoa mass and chocolate were determined, beside the determination of the total antiradical capacity. Concerning geographic origin, cocoa beans and processed products from Ecuador showed the highest levels of anthocyanins, followed by Nigeria and Cameroon. Generally, as cocoa beans were further processed, the levels of anthocyanins and flavan‐3‐ols decreased. The largest observed losses of phenolics occurred during roasting. A progressive decreasing trend in polyphenol concentration was observed in the other processed samples as well. Despite the original content of polyphenols in raw cocoa beans, technological processes imply a significant impact on cocoa quality, confirming the need of specific optimisation to obtain high value chocolate. 相似文献
2.
Shelf Life of Minimally Processed Honeydew, Kiwifruit, Papaya, Pineapple and Cantaloupe 总被引:3,自引:0,他引:3
R. E. O'CONNOR-SHAW R. ROBERTS A. L FORD S. M. NOTTINGHAM 《Journal of food science》1994,59(6):1202-1206
This study was to determine the shelf life of minimally processed honeydew melon, kiwifruit, papaya, pineapple, and cantaloupe stored at 4°C. Sensory assessments were carried out at 3-day intervals by highly trained panels until the end of shelf life. Microbiological counts were made immediately after dicing fruit and at the end of shelf life. Results indicated that both the length of shelf life and type of spoilage were related to fruit species. Minimally processed fruit had longer shelf life at 4°than at temperatures recommended for whole fruit when these were greater than 4°C. Spoilage of 4°C-stored kiwifruit, papaya and pineapple pieces was not a consequence of microbial growth. 相似文献
3.
研究了围长为2的n阶本原极小强连通有向图的1-指数集,证明了当n(≥5)为奇数时,En(1)={4,5,6,7,…,2n-5},无缺数段。 相似文献
4.
在对微创手术的作业要求及运动自由度等参数分析的基础上,提出了一种新型的RCM机构方案并对其进行详细的机械结构设计;运用D-H法进行机械臂的正运动学求解,并以此绘制机械臂的工作空间;基于对微创手术过程的分析,利用三维软件UG对远程运动中心机构典型运动过程进行了虚拟仿真,并用有限元分析软件ANSYS对重要部件进行强度分析。实验结果表明,所设计的远程运动中心机构能够较好地完成手术规划,满足微创手术要求。 相似文献
5.
本文阐述了数控铣镗床PLC程序设计方法和思路.并就用户特定机床面板PLC程序设计及用平旋盘实现铣镗、车复合加工的电气设计作了详细描述? 相似文献
6.
针对在微创手术中传统采用的钢针的不足,如与组织作用,双方均产生较大变形,造成很大误差,严重影响治疗效果。另外在手术中常常遇到一些重要的组织和器官要避开,传统的钢针无法满足需要。本文采用带斜尖的柔性针,完全利用进针时斜尖与组织的侧向作用力使针轴产生弯转。这样不但可以更精确控制针的轨迹,而且还能绕过障碍物准确达到靶点。本文首先简化了WebsterIII等人提出的柔性针非完整约束系统的自行车模型,提出了自行车前、后轮模型。在此基础上,又提出了更符合实际的带返程度的自行车模型,并进行了运动学建模研究。以实验数据拟合了模型中各参数,同时验证了此模型的合理性和准确性。 相似文献
7.
8.
Shuang Huang Mengyi He Chuanjie Yao Xinshuo Huang Deyuan Ma Qiqi Huang Jingbo Yang Fanmao Liu Xingqiao Wen Ji Wang Huijiuan Chen Xi Xie 《Advanced functional materials》2023,33(15):2214485
Current catheter devices in minimally invasive surgery still possess limited functional options, lacking multimodal integration of both sensing and therapy. Catheter devices usually operate outside the tissue, incapable to detect intra-tissue biochemical information for accurate localization and assessment of lesions during surgery. Inspired by the feature and functions of Petromyzontidae, here a multimodal core-shell microneedles-integrated bioelectronic catheter (MNIBC) for tissue-penetrating theranostics in endoscopic surgery is developed. The microneedle (MN) device possesses individually addressable functionality at single-MN tip resolution, enabling multiplex functions (a total of 11 functions distributed in three types of catheters) including biochemical sensing, myoelectric modulation, electroporation, and drug delivery in a submucosal environment. The MNIBC is prepared through hybrid fabrication and dimensionality reduction strategies, where the MN electrodes are functionalized with an MXene-carbon nanotube (MXene-CNT)-based electron mediator, addressing the challenge of reduced electrode sensitivity on ultra-small MN tip. The functionalities of MNIBC are demonstrated both ex vivo and in vivo on anesthetized rabbits via laparoscopy, simulated cystoscopy, and laparotomy. The MNIBC can effectively detect intra-tissue biochemical signals in the bladder, and offers localized electroporation and intra-tissue drug delivery for precise treatments of lesions. The versatile features of the MNIBC present a highly advanced platform for precise surgeries. 相似文献
9.
针对大规模分布式传感器网络提出一种拓扑三级分簇结构优化算法. 通过引入传感器休眠模式, 并考虑到分簇数目较多的情况, 对多个簇头节点采用生成最小刚性图的方法进行拓扑优化, 以实现传感器网络整体能量均衡,使传感器网络具有较好的连通性和鲁棒性. 仿真实验表明, 与已有相关算法相比, 采用所提出的算法可使网络延缓出现节点死亡现象, 有利于实现网络负载均衡, 并且网络中节点整体存活时间较长, 从而延长网络的生命周期.
相似文献10.
Performance of an Adaptive Controller for the Neuromuscular Blockade Based on Inversion of a Wiener Model 下载免费PDF全文
An adaptive controller based on a minimally parameterized parsimonious Wiener model for the effect of the muscle relaxant rocuronium in the neuromuscular blockade is presented. The controller structure combines inversion of the recursively identified static nonlinearity of the Wiener model with a positive compartmental control law for the linearized system. The overall strategy exploits the fact that the model has only two parameters, which are estimated by an extended Kalman filter. Due to the fact that the positive control law for total mass conservation of compartmental systems is only proven to be convergent for time‐invariant systems, the identification of the parameter in the linear block of the minimally parameterized parsimonious Wiener model is stopped when the controller is turned on. The controller was implemented in the platform Galeno and tested in simulation and in thirteen real cases of patients under general anesthesia. The good reference tracking results and robustness to noise show the reliability of the proposed strategy. 相似文献