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1.
通过对甘谷辣椒红色素进行提取,确定了其中的4种成分,研究了色素提取的最佳条件及色素的稳定性.结果表明:该色素含有辣椒红色素、辣椒玉红素、β-胡萝卜素、辣椒碱、二氢辣椒碱5种主要成分.色素在480 nm有最大吸收峰,该色素水溶性较差,油溶性较好,在pH值4~10时色调不变,具有良好的热稳定性.温度为90℃时,色素稳定.良好的耐酸碱性,耐光性较差,连续光照48 h,色素残存率为45%,1 mg/L Na+,Ca2+、Al3+溶液对色素最大吸收峰无明显影响,1 mg/L Cu2+,Fe2+溶液使色素最大吸收峰偏移.  相似文献   

2.
玫瑰花红色素的提取及其稳定性研究   总被引:3,自引:0,他引:3  
通过单因素和正交试验研究了玫瑰花红色素的提取工艺.结果表明:玫瑰花红色素属花青素类,提取的最佳条件为:70%(V/V)乙醇为溶剂、pH值为1、物料比(m/V)为1∶ 8、浸提温度60℃、时间为1 h.稳定性研究表明玫瑰花红色素对光和热敏感,在不同的pH值下表现出不同的颜色;金属离子Na 、Zn2 、Ca2 对该色素无明显影响,Cu2 使该色素颜色向黄色变化,而Fe3 则会使玫瑰花红色素的颜色发生较大的改变;玫瑰花红色素对还原剂Na2SO3较稳定,对氧化剂H2O2则很敏感.  相似文献   

3.
鸡血李红色素稳定性的动力学研究   总被引:1,自引:0,他引:1  
研究从鸡血李中提取出的红色素的稳定性及热降解动力学 结果表明 ,pH值不仅影响色素的色泽 ,同时也影响色素的降解 ,pH =5时最稳定 ;Vc ,Fe3+ ,Cu2 + 离子促进色素降解 ,而蔗糖、果糖等对色素无促进作用 色素适合酸性食品着色  相似文献   

4.
石榴花红色素是一种优质的天然红色索,在医药、食品、轻工业等行业具有广泛的应用价值。本文以石榴花作为原料,对石榴花红色素的提取条件进行了系统研究,采用了单因素和正交试验确定了浸提溶剂浓度、提取温度、料液比,提取时间及提取次数对石榴花红色素提取的影响。结果表明:石榴花红色素的最大吸收波长λmax=500nm,从石榴花中提取色素的最佳工艺条件:以pH(2~3)的50%的乙醇为浸提剂、浸提温度为40℃、提取时间3h、料液比为1:10、提取次数4次。  相似文献   

5.
五味子红色素的提取工艺   总被引:2,自引:0,他引:2  
采用pH=3的乙醇提取五味子色素, 通过单因素实验设计分别研究了提取温度、 时间、 材料与溶剂比例3种因素对五味子色素提取率的影响. 通过正交实验法, 以五味子红色素的提取率为主要指标, 对pH=3的乙醇提取五味子红色素的工艺进行优化, 确定了五味子红色素的最佳提取工艺: 以5倍量pH=3的乙醇溶液为溶剂, 75 ℃下浸提2 h. 通过对五味子红色素的红外光谱进行解析, 确定其属于吲哚类色素.  相似文献   

6.
唐菖蒲花红色素稳定性研究   总被引:1,自引:0,他引:1  
以唐菖蒲花瓣为实验材料,研究了光、热、紫外线(365nm)、PH值、还原介质、氧化介质、蔗糖、防腐剂、金属离子等对红色素稳定性的影响.结果表明:该色素为水溶性花青苷类色素,在PH为1时耐光、耐热性较强,并具有较强的抗辐射能力,但耐还原性、氧化性较差;蔗糖、苯甲酸钠对色素稳定性有影响,金属离子K 、Na 、Ca2 、Cu2 、Zn2 对色素溶液色泽影响很小,Mg2 、A13 对唐菖蒲花红色素有增色作用,而Fe3 的加入改变了色素溶液的颜色,对色度有一定影响.研究结果表明,该红色素适用于在低糖、酸性浓缩食品中使用,是一种值得开发的天然保健色素.  相似文献   

7.
:研究了从华中五味子果实中提取的色素的理化性质。该色素在酸性条件下显红色。对短期高温耐受性好。常见金属离子Cu2+、Ca2+、Mg2+、Al3+对此色素无影响。软饮料经五味子红色素着色后色泽柔和自然,并且有一定增味作用  相似文献   

8.
采用水提法从桑葚中提取桑葚红色素,使用大孔树脂纯化后研究其在果冻中的稳定性.结果表明,提取温度为80℃,提取时间为50 min,液料比为10∶1时,取得最佳提取效果,得到桑葚红色素提取率为87.56%.色素质量浓度为0.08 mg/m L时吸附率达到最大,pH值为1,体积分数为70%(V/V)的乙醇溶液解吸的最好.动态吸附时穿透点为420 m L(10.0 g树脂).木糖醇对果冻中的桑葚红色素具有保护作用;柠檬酸虽在短时间内对桑葚红色素的的稳定性有破坏作用,但整体来说影响不大;Ca~(2+)、Zn~(2+)对桑葚红色素具有破坏作用,Na~+、Fe~(2+)对桑葚红色素的稳定性影响不大,Mg~(2+)对色素有保护作用;光照对桑葚红色素影响极大.  相似文献   

9.
和田玫瑰花红色素的提取及性质研究   总被引:2,自引:0,他引:2  
文章介绍了和田玫瑰花红色素的提取,研究了光,温度,酸碱性,氧化剂,还原剂,防腐剂,添加剂,金属离子对和田玫瑰花红色素稳定性的影响与理化性质进行了初步研究。玫瑰花红色素的耐光性较好,耐热性很好,可做食品的着色剂,但在使用过程中应尽量避免长时间光照。添加剂对红色素的影响不大,防腐剂对红色素影响不大。Mg2 ,Ba2 ,Na ,K ,Cd2 ,Ca2 对色素的稳定性无影响,Al3 ,Cu2 ,Fe3 对色素有一定影响,在提取和保存过程中应避免使用铁器。  相似文献   

10.
探讨了长白山笃斯越橘冷冻果红色素的提取条件及外界因素对越橘色素稳定性的影响.结果表明:长白山笃斯越橘红色素乙醇溶液最大吸收峰的波长在526 nm处.长白山笃斯越橘色素易溶于乙醇等有机溶剂,不同提取液对色素的提取效果有一定的影响.越橘红色素的乙醇溶液呈深红色,澄清透明,丙酮溶液微溶,呈红褐色.有絮状物;最佳提取条件为85...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
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   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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