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1.
通过单因素实验和正交试验以感官评定及固形物溶出率为评价指标对香菇菌汤煮制工艺进行优化,并采用高效液相色谱技术对煮制后香菇及汤液中非挥发性特征风味物质进行测定。结果表明,当煮制温度为120℃、煮制时间为45min、香菇质量浓度为0.050g/mL时,香菇菌汤感官评价及固形物溶出率较好。在煮制过程中,香菇中风味物质逐渐向汤液中转移,使得汤液中可溶性糖醇、有机酸、呈味核苷酸等非挥发性风味物质含量显著高于煮制后香菇中含量。除此之外,在煮制后汤液中,特征性风味氨基酸含量也显著高于煮制后香菇中含量。但是,与新鲜香菇相比风味氨基酸在煮制后汤液及香菇中绝大多数含量有所降低。  相似文献   

2.
以猪血为材料,运用热变性和乙醇除杂蛋白,再经过旋转蒸发、离子交换、活性炭脱色、浓缩得到血活素产品,并对产品进行了性能分析。结果表明:该产品已基本无大分子蛋白,干物质含量在25.6 mg/mL。微量金属含量为铜0.04 mg/mL、锌0.003 2 mg/mL、铁0.4μg/mL。运用该产品代替小牛血清培养细胞,细胞生长较明显,虽然与小牛血清培养效果存在差距,但可看出该产品在细胞培养方面具有潜在的开发前途。  相似文献   

3.
本文以CTAB为包被试剂合成了球形、棒状和三角形三种不同形态的纳米金颗粒,研究了它们对金黄色葡萄球菌(Staphylococcusaureus,S.aureus)和大肠杆菌(Escherichiacoli,E.coli)杀菌性能的差异.通过平板计数法和浊度法;确定了它们对两种菌的最小杀菌浓度(minimum bactericidal concentrations,MBC)和最小抑菌浓度(minimum inhibitory concentrations,MIC).棒状纳米金、三角形纳米金、球形纳米金对大肠杆菌的MIC分别为0.65μg/mL、3.71μg/mL、21.21μg/mL,MBC分别为1.30μg/mL、11.09μg/mL、21.21μg/mL;对金黄色葡萄球菌的MIC分别为0.26μg/mL、0.56μg/mL、2.65μg/mL,MBC分别为0.52μg/mL、1.11μg/mL、2.65μg/mL.结果表明无论是对大肠杆菌还是金黄色葡萄球菌,棒状纳米金的杀菌效果均高于其它两种形态,并且三种不同形态的纳米金对金黄色葡萄球菌的杀菌效果均优于大肠杆菌.  相似文献   

4.
蒜头果果仁中7种金属元素含量的测定   总被引:1,自引:0,他引:1  
采用湿法硝酸—高氯酸对蒜头果果仁进行了消解前处理,用电感耦合等离子体原子发射光谱法(ICP-AES)测定了蒜头果果仁中Al、Ca、Fe、K、Mg、Mn、Zn 7种金属元素的含量。结果表明,7种元素含量分别为18.65μg/g,192.6μg/g,9.946μg/g,12.12 mg/g,2.259 mg/g,25.55μg/g和23.46μg/g。元素的检出限为0.001 2~0.169 8μg/mL,RSD=1.04%~7.58%(n=5),回收率为97.49%~109.6%。建立了蒜头果果仁中7种金属元素含量测定方法。该方法简便、快速,测定结果准确可靠。  相似文献   

5.
虫草真菌克列特尼棒束孢霉菌丝体主要成分分析   总被引:2,自引:0,他引:2  
从新鲜冬虫夏草上分离得到一株虫草真菌,经鉴定定名为克列特尼棒束孢霉(Isaria cretacea Morris)。并对冬虫夏草和此菌干菌丝体的主要化学成分进行了比较。结果表明,冬虫夏草与克列特尼棒束孢霉的粗蛋白含量相应为23.39mg/100mg和23.69mg/100mg;氨基酸含量为6.741mg/100mg和5.762mg/100mg;虫草菌素含量为66.99μg/g和249.71μg/g。此外,对二者的甘露醇和麦角甾醇结晶的熔点、紫外光谱、红外光谱等也进行了分析,表明二者均具有相同的性质。  相似文献   

6.
猕猴桃中维生素C的高效液相色谱分析   总被引:2,自引:0,他引:2  
用0.1%的草酸作为流动相,高效液相色谱法测定了猕猴桃中维生素C的含量.当维生素C浓度在0~500μg/mL范围内浓度与色谱峰面积呈正比关系,标准工作曲线线性相关系数为0.9915.实验结果表明:国产陕西猕猴桃维生素C含量最高,含量为234.41 mg/100 g,进口新西兰金果维生素C含量次之,含量为187.33 mg/100 g,进口新西兰绿果维生素C含量最低,含量为109.42 mg/100 g.  相似文献   

7.
川藏地区产油菜籽中有效化学成分含量比较研究   总被引:1,自引:0,他引:1  
目的:比较川藏地区产油菜籽中有效化学成分的含量.方法:以有效化学成分含量为指标,采用紫外分光光度法分别测定油菜籽中酚酸、植酸、硫甙以及原花青素的含量.结果:四川产油菜籽中酚酸含量为76.7 mg/g,植酸含量为55.0 mg/g,硫甙含量为20.4μmol/g,原花青素含量为518.6μg/g;西藏产油菜籽中酚酸含量为52.4 mg/g,植酸含量为76.7 mg/g,硫甙含量为128.7μmol/g,原花青素含量为870.2μg/g.结论:四川和西藏地区产油菜籽中有效化学成分的含量具有较明显的差异.  相似文献   

8.
目的 基于Nrf2/HO-1铁死亡信号通路探讨补阳还五汤对血管紧张素Ⅱ(AngiotensinⅡ,AngⅡ)诱导的H9c2大鼠心肌细胞铁死亡的影响。 方法 体外培养H9c2心肌细胞,分别设正常组(ZC)、模型组(MX)、补阳还五汤低剂量组(BD)、补阳还五汤中剂量组(BZ)、补阳还五汤高剂量组(BG)和阳性对照组(YX)。除正常组外,其余各组采用1μM血管紧张素Ⅱ(AngⅡ)建立心肌细胞损伤模型,同时补阳还五汤低、中、高剂量组分别用含0.5mg/mL、1mg/mL、2mg/mL补阳还五汤的培养基培养,阳性对照组使用含10μM铁死亡抑制剂Ferrostatin-1(Fer-1)的培养基培养,24h后收集细胞。采用CCK-8法检测各组心肌细胞活性;细胞铁含量检测试剂盒测定细胞内铁含量;免疫荧光染色法检测各组Nrf2蛋白表达;q-PCR法检测各组细胞核转录相关因子2(Nrf2)、血红加氧酶-1(HO-1)、谷胱甘肽过氧化物酶4(GPX4)的mRNA表达水平;ELISA试剂盒检测细胞谷胱甘肽(GSH)和GPX4的蛋白表达水平;Western blot法检测Nrf2和HO-1的蛋白表达。结果 补阳还五汤高剂量组可明显提高AngⅡ诱导的H9c2细胞活力下降,减少AngⅡ条件下铁含量(P﹤0.05);与模型组相比,补阳还五汤高剂量组能显著逆转AngⅡ诱导的H9c2细胞GSH、GPX4、Nrf2和HO-1的基因和蛋白表达水平的下降,使AngⅡ条件下受到抑制的Nrf2表达增加,与阳性对照组结果一致。结论 补阳还五汤可能通过Nrf2/HO-1信号通路调控心肌细胞铁死亡从而保护高血压继发的心肌损伤。  相似文献   

9.
本文提出微波高压消解-火焰原子吸收光谱法(AG-FAAS)测定食用菌中痕量铜、锌、铁和锰的方法.该方法检出限Cu2 、Zn2 、Mn2 为:1.0×10-9g/mL和Fe3 为:5.0×10-9g/mL.Mn2 、Fe3 Cu2 和Zn2 的含量分别在0.250~4.000、0.500~2.500、0.100~0.500和0.300~1.500μg/mL范围内符合比尔定律,相关系数为0.9997~0.9999.此法用于茶树菇、香菇中铜、锌、铁和锰含量的测定,结果令人满意.  相似文献   

10.
为了对中药方剂温脾养胃颗粒进行科学的质量控制,本研究建立了君药黄芪和白芍的主要成分含量测定方法并应用于制剂的稳定性研究。分别建立适用于温脾养胃颗粒中黄芪甲苷和芍药苷含量测定的UHPLC-MS/MS和HPLC-UV方法,并以芍药苷含量为指标,通过影响因素试验和经典恒温试验进行制剂稳定性研究,拟定贮藏条件,预测有效期。结果表明,黄芪甲苷和芍药苷的线性范围分别为1~60μg/mL(r=0.999 8)、10~100μg/mL(r=0.999 6),颗粒剂中黄芪甲苷和芍药苷的平均含量分别为0.126 mg/g、1.02 mg/g。颗粒剂的指标成分含量受温度及光照影响较小,但对环境湿度相对敏感,应密封置阴凉干燥处保存,有效期至少为1年。  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.
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   

13.
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   

14.
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   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
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   

17.
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   

18.
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   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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