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1.
用热分析方法对魔芋品种鉴别进行了研究.采用热重分析(TG-DTG)在静态空气气氛下对白魔芋原粉、花魔芋原粉、红魔芋原粉的TG-DTG曲线进行分析,根据其图谱的特征差异进行鉴别.研究发现,在DTG曲线上白魔芋原粉、花魔芋原粉、红魔芋原粉分别在272.8、270.8、265.1℃以上时逐渐热解炭化,分别在469、476.3、433.5SO以上开始燃烧,不同魔芋品种的DTG曲线有明显差别,从峰的位置可快速简便的鉴别魔芋品种.  相似文献   

2.
为了建立一种快速分析鉴别不同类型的中药昆布的方法,采用热重—微分热重(TG-DTG)和差热分析(DTA)对不同产地的海带和昆布进行热分析研究.以α-Al2O3为参照物,N2为气氛的条件下,固定反应的升温速率和温度范围,进行图谱峰形的比较鉴别.结果表明,不同产地的海带和昆布之间TG、DTG、DTA图谱中峰形有所不同,利用海带和昆布热分析图谱的差异,可以快速鉴别不同产地的中药昆布.  相似文献   

3.
骨类垃圾为厨余垃圾中的重要组成部分,为了缓解厨余垃圾的处理压力,本文选取无烟煤与烟煤分别按照不同比例与牛骨掺混,采用ZTC-B型综合(同步)热分析仪对其混合燃烧过程进行了热重分析,并对结果进行了动力学分析。结果表明:煤与牛骨单独燃烧的TG-DTG曲线差异明显;掺混燃烧时随着混合物中牛骨质量分数的增加,DTG峰值温度向着低温区偏移,整体燃烧温度区间变窄,综合燃烧特性指数不断降低,燃尽特性指数不断升高;掺混燃烧过程中会产生协同作用,无烟煤、烟煤与牛骨的混合物在400 ℃左右产生了抑制作用,其相对值分别为-8 %与-4 %,在524 ℃和627 ℃左右产生了促进作用,其相对值分别为7 %和9 %;动力学分析表明采用2个连续一级反应模型可以很好地描述其掺烧过程。  相似文献   

4.
采用热重法(TG)测定了槲皮素和芦丁的TG-DTG曲线.结果表明:槲皮素的DTG曲线有一个明显的失重峰,峰顶温度为349℃,失重率为33.32%.芦丁的DTG曲线有三个失重峰,在278℃的失重峰最为明显,失重率为29.71%.用TG-DTG法对两者在非等温条件下进行热分解动力学研究,把从TG-DTG曲线中取得的数据和30个不同的方程采用Achar微分法和Madhusudanan-Krishnan-Ninan(MKN)积分法对其进行非等温分解动力学研究,得到动力学参数(表观化学能E和频率因子A)和分解动力学机理及方程.得出结论:槲皮素和芦丁动力学方程均为da/dt=A exp(-E/RT)3/2(1-α)4/3[1(1-α)1/3-1]-1,其分解机理符合三维扩散机理Three-dimensional,3D.二者的表现化学能分别为93.63和107.86kJ·mol-1,ln A 分别是25.80和39.57 s-1.  相似文献   

5.
复合涂膜对草莓保鲜效果的研究   总被引:1,自引:0,他引:1  
采用魔芋精粉作为被膜剂,对草莓进行CaCl2、水杨酸(SA)、中药浓缩液等浸泡处理,以浸钙浓度、浸钙时间,水杨酸浓度、中草药浓度、魔芋精粉浓度五个因素作五水平五元二次正交旋转组合试验,经过线华回归分析,建立模型得出:在保证好果率大于75%的情况下,经以浓度为5.8%的CaCl2浸泡2min,再以孽度为0.0397%的SA、0.16%的魔芋精粉、40%的中药为配方制得的复合液涂膜,对草莓果实有较好的保鲜效果。  相似文献   

6.
综述了魔芋精粉各种生产工艺、魔芋精粉的性质以及改性研究的情况。  相似文献   

7.
以邵阳地方风味豆腐为基准,利用对豆腐部分理化性质的测量与观察,以对照实验方法研究魔芋精粉在豆腐生产中的合理添加量.实验表明,魔芋精粉、熟石膏粉和精石灰的最佳添加量为:以1L豆浆为基准,添加1.0g熟石膏粉、2.0g魔芋精粉、0.8g精石灰粉.在此条件下,豆腐的平均出品率可增加18.5%,并且可以在相同含水量的前提下提高豆腐的相对硬度(32.7%)与韧性.从而改变传统豆腐制作工艺中出现的易碎、韧性差等不良现象.  相似文献   

8.
以胡萝卜、板栗粉为主料、魔芋精粉、卡拉胶为凝胶剂研究了板栗糕的加工技术。根据原辅料对板栗糕的色泽、口感、成型性和质地的影响,经研究认为,板栗糕的最佳配方是:栗粉15g,胡萝卜20g,水130ml,卡拉胶1.0g,魔芋精粉0.5g,白砂粉30g。其工艺流程是:先用少量水将主料胡萝卜和板栗粉充分混匀成糊,再用水溶胀卡拉胶和魔芋精粉,然后将两者混合,微火熬制,不断搅拌,趁热装模,冷却后,脱模制得产品。制品色泽浅红,有板栗清香,口感软而富弹性。  相似文献   

9.
本文制备了稳定的题目化合物,对所得样品进行了表征。采用TG-DTG法研究了它们的热分解行为,通过IR对反应物、中间产物和最终产物进行了鉴别。发现中间产物有低水合物和碱式盐,最终产物是氧化镜。进行了样品一些脱水过程的动力学研究,借助不同升温速率下的TG—DTG曲线,用Kissinger法计算了它们脱水的表观活化能值,利用DSC法求出了它们的脱水焓值。  相似文献   

10.
研究以魔芋精粉和鲜牛奶为原料制备功能性酸奶的工艺优化,采用磷酸法提纯魔芋精粉并以直投式发酵剂进行发酵。在单因素实验的基础上,通过Box-Benhnken响应面法得出功能性魔芋酸乳制备的最佳工艺条件为:糖添加量6.14%,发酵剂添加量6.71%,魔芋精粉添加量0.43%,发酵时间4h。直投式发酵剂具有类型多、活力强的优点,采用此发酵剂制备魔芋酸乳的过程简单,容易推广。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
14.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

15.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

16.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

17.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

18.
The concept of nanopore analysis, using the pore-forming protein a-hemolysin to detect individual nucleic acids at a single-molecule level, was first proposed in 1996. Over the past two decades, tremendous progress has been made in the nanopore field, and nanopore analysis has become a label-free and high-throughput method for probing bio- molecules and other analytes with single-molecule sensi- tivity, especially holds the promising for "third generation" DNA sequencing. However, challenges still remain in the experimental strategies and the design of whole nanopore-based instruments. Here, we proudly present a special topic dedicated to the topic of "Nanopore Analysis", with 8 reviews/articles providing up to date coverage of the experimental strategies, theoretical calcu- lations and simulations, and instrument design. Reviews and articles on the experimental strategies cover control of DNA partitioning into a nanopore, detection of target DNA, and the advantages of nanopore-based DNA sequencing. The theoretical calculations and simulations discuss the translocation behavior of DNA, and an inte- grated measurement system and data analysis software are presented for instrument design.  相似文献   

19.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

20.
<正>1 Introduction Endeavours on learning methods have long occupied the mind spaces of scholars and there have been theories abound on how people learn and in what way organisations can use some of the knowledge gained in the art of learning to maximise human productivity.While the theories by themselves are not solutions to problems,they are steps of inquiry that provide us with interesting perspectives that we can use to extend our knowledge of the dimensions of learning.This paper is an exploratory work on the theories postulated by three notable scholars including Zimmerman  相似文献   

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