浓缩菠萝汁生产线

<正>菠萝(pineapple)也叫凤梨,它印香蕉、荔枝、芒果并列为世界四大名果,以气味芳香,果肉甜美和艳丽的美观外型蜚声全球。     

Fabrication of electric papers of graphene nanosheet shelled cellulose fibres by dispersion and infiltration as flexible electrodes for energy storage

An electrically conductive and electrochemically active composite paper of graphene nanosheet (GNS) coated cellulose fibres was fabricated via a simple paper-making process of dispersing chemically synthesized GNS into a cellulose pulp, followed by infiltration. The GNS nanosheet was deposited onto the cellulose fibers, forming a coating, during infiltration. It forms a continuous network through a bridge of interconnected cellulose fibres at small GNS loadings (3.2 wt%). The GNS/cellulose paper is as flexible and mechanically tough as the pure cellulose paper. The electrical measurements show the composite paper has a sheet resistance of 1063 Ω□(-1) and a conductivity of 11.6 S m(-1). The application of the composite paper as a flexible double layer supercapacitor in an organic electrolyte (LiPF(6)) displays a high capacity of 252 F g(-1) at a current density of 1 A g(-1) with respect to GNS. Moreover, the paper can be used as the anode in a lithium battery, showing distinct charge and discharge performances. The simple process for synthesising the GNS functionalized cellulose papers is attractive for the development of high performance papers for electrical, electrochemical and multifunctional applications.     

新型紫外光产酸剂的合成及其光聚合动力学研究

以2-硝基噻吩,甲基磺酰氯及苯乙腈为原料合成了一种紫外光产酸剂(5-甲磺酸酯亚胺-5H-噻吩-2-亚基)-苯基-乙腈(MTPA),通过傅里叶红外光谱仪、核磁共振仪和紫外吸收光谱仪及热重分析对所合成的产物的结构和性能进行了表征,并利用实时红外(RT-IR)对该引发剂进行了光聚合反应动力学研究。考察了单体、产酸剂浓度对引发速率及单体转化率的影响。结果表明,在一定浓度范围内,随着引发剂浓度增大,聚合速率加快,最终的双键转化率也增高。     

Transfer function measurement for the SSRF SRF system

A digital transfer function measurement system has been embedded in the low-level radio frequency (LLRF) system of the storage ring of the Shanghai Synchrotron Radiation Facility. The measurement results indicate that the decreased control accuracy at high current is primarily owing to ripples from the high-voltage power supply, the transient beam loading effect, and the digital aliasing effect. The current LLRF algorithm is not able to suppress these disturbances.     

基于吉布斯采样的TFBS识别算法研究

计算机方法识别转录因子结合位点（TFBS,也称“模式”）是目前生物信息学的一个很有吸引性和挑战性的课题。吉布斯采样识别模式的算法本质上是一个启发式搜索方法,容易陷入非全局最优的局部最大值。为此,提出了一种改进的吉布斯采样策略YGMS（Yeast Gibbs Motif Sampler）采识别酿酒酵母共表达基因调控区域转录因子结合位点。在酵母的共调控基因序列的数据集测试中,YGMS比其他几个基于吉布斯采样算法更有效地识别出真实模式序列,在一定程度上提高了算法的性能。     

非对称门限服务与完全服务的性能解析

为了能在无线传感器网络选择一种合适的非对称轮询服务,对非对称门限服务与完全服务的性能进行了分析和比较判定了两种服务在不同情况下其各自特性的优越性.通常在分析非对称轮询服务的时候,一般采用由浅入深的分析方法.所以两队列的服务模型将会作为基础,借此进行拓展,对多队列的非对称服务进行解析.分析过程中使用了马尔科夫链和概率母函数的方法构建了服务系统的数学模型.通过对数学模型的解析给出了非对称服务系统平均排队队长和平均查询周期的表达式.根据理论值的精确计算与实验仿真值的对比结果,可以验证出二者是保持一致的.并且,对未来在无线传感器网络中实现非对称的门限服务和完全服务进行了初步设计,可以实现将多跳的路由协议,转变成单跳的轮询协议,减少数据传输的冲突性.     

Motor Fault Diagnosis Based on Short-time Fourier Transform and Convolutional Neural Network

With the rapid development of mechanical equipment, the mechanical health monitoring field has entered the era of big data. However, the method of manual feature extraction has the disadvantages of low efficiency and poor accuracy, when handling big data. In this study, the research object was the asynchronous motor in the drivetrain diagnostics simulator system. The vibration signals of different fault motors were collected. The raw signal was pretreated using short time Fourier transform (STFT) to obtain the corresponding time-frequency map. Then, the feature of the time-frequency map was adaptively extracted by using a convolutional neural network (CNN). The effects of the pretreatment method, and the hyper parameters of network diagnostic accuracy, were investigated experimentally. The experimental results showed that the influence of the preprocessing method is small, and that the batch-size is the main factor affecting accuracy and training efficiency. By investigating feature visualization, it was shown that, in the case of big data, the extracted CNN features can represent complex mapping relationships between signal and health status, and can also overcome the prior knowledge and engineering experience requirement for feature extraction, which is used by traditional diagnosis methods. This paper proposes a new method, based on STFT and CNN, which can complete motor fault diagnosis tasks more intelligently and accurately.     

棉籽中单氰胺储藏稳定性及残留行为

目的 建立测定棉籽中单氰胺残留的液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS),研究棉籽中单氰胺的储藏稳定性和大田施药后单氰胺在棉籽中的残留行为及其消解规律.方法 样品用乙腈-水溶液(80:20,V:V)提取,离心后用丹磺酰氯进行衍...     

面皮加工与品质研究进展

面皮作为我国西北地区的传统特色小吃,因其口感独特而深受人们的喜爱。随着社会的发展和生活节奏的加快,面皮已经逐渐成为居民日常方便食品之一,其消费量逐年增加。然而,面皮传统加工和品质无法满足其工业化生产和长距离物流运输的需求,限制其进一步发展。本文结合相关文献,就面皮的加工及工艺改进、品质变化及应对方法和面皮包装等研究进展进行综述。食用胶的添加、加工温度和pH是面皮加工的关键影响因素,其中添加合适食品添加剂是控制面皮老化的有效手段;巴氏杀菌和高压高温杀菌技术可有效控制面皮霉变;真空包装是目前面皮主要的包装形式;进一步明确面皮的加工工艺、品质变化及其预防措施,并对其今后研究提出建议,以期为面皮工业化生产提供参考。     

真空提取核桃粕多酚的抗氧化活性研究

目的 探究真空提取的核桃粕(walnut meal)多酚的抗氧化活性。方法 以非真空条件下提取的多酚为对照,采用超声波辅助真空法提取核桃粕多酚,用HPD-100型大孔树脂对多酚进行纯化,福林酚(Folin-Ciocalte)法测定多酚含量,通过试剂盒检测多酚对1,1-二苯基-2-苦基肼自由基(1,1-diphenyl-2-picrylhydrazyl,DPPH)、超氧阴离子自由基的清除率及Fe³⁺还原能力(ferric reducing antioxidant power,FRAP)来评价其体外抗氧化活性,用cck8(cell countingkit-8)法测定不同浓度的核桃粕多酚对HepG2细胞的毒性作用,确定3个无毒性作用浓度,以770μmol/L的H₂O₂诱导HepG2细胞建立氧化应激损伤模型,通过测定HepG2细胞中丙二醛(malonicdialdehyde, MDA)含量、超氧化物歧化酶(superoxide dismutase, SOD)活力、谷胱甘肽(glutathione, GSH)含量探究12.5、25...