印度块菌粗多糖的提取及抗氧化活性研究

采用正交试验研究了热水浸提法提取印度块菌(Tuberindicum Cooke&Massee)子实体粗多糖(TICP)的最优工艺,根据方差分析结果确定了热水浸提法的最优工艺为:料液比1∶15,提取时间120 min,提取温度100℃,提取2次,多糖提取率为6.790 2%.用95%乙醇对粗多糖进行醇沉,然后利用总抗氧化能力(T-AOC)测定法、羟基自由基(OH.)清除法、铁离子螯合能力及测定还原能力等方法对上述印度块菌粗多糖的抗氧化活性进行评价,结果显示块菌粗多糖对羟基自由基的清除活性最高,其EC50值为0.26 mg/mL,其次为还原能力和铁离子螯合能力,其EC50值分别为1.15 mg/mL、2.80 mg/mL,同时块菌粗多糖具有较好的总抗氧化能力(T-AOC),当浓度为20 mg/mL时,其总抗氧化能力为72.06 U/mL.     

雪樱子粗多糖提取、纯化工艺及抗氧化活性研究

以雪樱子为原料,优化雪樱子粗多糖水提醇沉提取法及AB-8型树脂纯化工艺。并以维生素C作为对比,以羟自由基清除能力、超氧阴离子自由基清除能力、DPPH自由基清除能力作为指标,对雪樱子粗多糖进行了体外抗氧化活性的测定。结果表明,雪樱子粗多糖的优化提取工艺为:醇沉乙醇体积分数80%、料液比(g/mL)1∶20、提取温度95℃、提取时间6h,粗多糖得率为(1.421±0.081)mg/g。雪樱子多糖优化纯化工艺为:上样液质量浓度1.00mg/mL,上样液pH值5,吸附速率2BV/h,乙醇洗脱剂体积分数25%,洗脱速率2BV/h,回收率为44.99%±1.23%。雪樱子粗多糖具有较好的体外抗氧化活性。研究结果为雪樱子多糖活性分析和功能性产品开发提供了技术支持。     

甘西鼠尾草水溶性多糖提取工艺的优化及体外抗氧化活性测定

本文利用超声波辅助水提醇沉法提取甘西鼠尾草粗多糖,应用单因素和Box-Behnken响应面法进行提取工艺优化.对甘西鼠尾草粗多糖进行脱色素、脱蛋白处理得到初步纯化多糖,并对粗多糖和初步纯化多糖进行体外抗氧化活性的测定.结果表明,甘西鼠尾草粗多糖的最佳提取条件为:液料比31:1 m L/g、提取时间2. 7 h、提取温度75℃、超声波功率300 W.在此条件下,甘西鼠尾草粗多糖的提取率为6. 568%,与预测值基本一致.清除自由基实验表明,在一定浓度范围内,对·OH自由基清除活性最高清除率达64. 34%;对DPPH清除活性最大清除率达83%.     

脱脂沙苑子乙醇提取物的体外抗氧化活性研究

通过测定脱脂沙苑子乙醇提取物(ESA)对1,1-二苯基-2-苦苯肼自由基(DPPH·)、超氧阴离子自由基(O-·2)和羟基自由基(·OH)的清除能力、对Fe2 诱导的脂质过氧化反应的抑制作用、还原力和总抗氧化力,评价ESA的体外抗氧化活性,并与公认的抗氧化剂维生素C作了对照.结果表明,ESA有一定的DPPH·清除能力(IC50=419.1μg/mL)、较强的超氧阴离子清除能力(IC50=117.9μg/mL)和羟基自由基清除能力(IC50=224.4μg/mL),能有效的抑制脂质过氧化(IC50=1.70 mg/mL),有良好的总抗氧化力,说明沙苑子具有明显的抗氧化活性.     

小花忍冬叶提取物的抗氧化活性

通过T-AOC法、DPPH法、Fenton法体外抗氧化试验,对小花忍冬叶乙醇提取物的各个萃取部位进行抗氧化活性研究.结果表明,小花忍冬叶5种提取物均具有不同程度的抗氧化活性,乙酸乙酯部分羟自由基清除活性最强,IC_(50)值为67.0μg/mL;清除DPPH·自由基IC_(50)为7.2μg/mL,均高于对照Vc.研究结果提示小花忍冬叶乙醇提取物乙酸乙酯萃取部分具有很强的抗氧化活性,可作为一种新型的天然抗氧化剂和自由基清除剂,具有良好的开发前景.     

针毛鳞盖蕨不同溶剂萃取物抗氧化及其抑制α-葡萄糖苷酶活性研究

以针毛鳞盖蕨为研究对象,用体积分数95%乙醇提取后,依次用石油醚、乙酸乙酯、正丁醇3种有机溶剂萃取得各萃取物,分别测定其多酚含量,通过DPPH·和ABTS~+·清除法及PNPG法评价针毛鳞盖蕨乙醇粗提物及不同溶剂萃取物的体外抗氧化活性及降血糖活性.实验结果表明,在各萃取物中,乙酸乙酯萃取物的多酚含量最高(34.8%);针毛鳞盖蕨乙醇粗提物及各萃取物均具有一定的抗氧化和抑制α-葡萄糖苷酶活性.其中,乙酸乙酯萃取物具有显著的DPPH·清除能力、ABTS~+·清除能力及α-葡萄糖苷酶活性抑制能力,且其α-葡萄糖苷酶抑制活性IC_(50)=(5.3±0.8)μg/mL高于阳性对照阿卡波糖IC_(50)=(103.7±5.1)μg/mL.     

开口箭多糖含量测定及生物学活性研究

采用水提醇沉法提取开口箭多糖,三氯乙酸法除蛋白,蒽酮-硫酸法测定多糖含量。在体外抗氧化模拟条件下研究开口箭粗多糖对羟自由基(.OH)、过氧化氢(H2O2)和二苯代苦味酰肼基自由基(DPPH.)的清除作用,细胞培养板液体稀释法测定开口箭多糖的抑菌作用。研究结果表明:开口箭多糖含量为3.7%,粗多糖具有一定的清除.OH、H2O2和DPPH.能力,其中对H2O2具有较强的清除作用。与Vc为对照,开口箭多糖的抗氧化能力不同程度的弱于Vc。开口箭多糖对金黄色葡萄球菌、大肠埃希氏菌、枯草芽胞杆菌和白假丝酵母菌4种供试菌株均有较好的抑制作用,且粗多糖的抑菌杀菌作用强于去蛋白多糖。研究表明,开口箭多糖具有很好的抗氧化活性和较强的抑菌杀菌活性。     

多种体系中NaHS抗氧化活性的研究

采用邻苯三酚自氧化法、硫代巴比妥酸比色法、DMPD法、甲基紫法和SDS-PAGE法,检测了NaHS对超氧阴离子的清除能力、脂质过氧化的抑制作用、DMPD.+自由基的清除能力、清除羟自由基的能力及蛋白质氧化降解的保护作用.研究结果表明,NaHS在各体系中均具有很强的作用,且呈浓度依赖关系.脂质过氧化的半抑制浓度为22.04μg/mL,对超氧阴离子、DMPD和羟自由基的半清除率分别为3.44、1.26和54.07μg/mL,活性均远高于人工合成抗氧化剂Trolox.对蛋白质的氧化损伤在2μg/mL时已有明显的保护作用,作用也比Trolox强.这些结果表明NaHS在这些反应系统中均表现出突出的抗氧化活性.     

两种苦瓜多糖对人白血病细胞体外增殖的影响

采用热水浸提法提取苦瓜粗多糖,经DEAE-52纤维素层析柱对其进行分离纯化,以蒸馏水和0.1mol/L NaCl进行洗脱,分别得到水洗苦瓜多糖(W-MCP)和盐洗苦瓜多糖(S-MCP).采用MTT法对这两种苦瓜多糖对人白血病系细胞K562体外增殖抑制作用进行研究,并对其抗氧化(O2-.、DPPH和脂质过氧化)活性进行测定.结果显示:W-MCP和S-MCP对K562细胞的抑制作用随着时间延长而增强,48h时抑制率趋于稳定,在72h、400μg/mL下W-MCP和S-MCP的最大抑制率分别为30.46%和28.61%;W-MCP和S-MCP对O2-.的最高清除率分别为58.52%和44.71%,对DPPH自由基的清除作用随浓度的升高而降低,最高清除率分别为19.01%和30.11%,对脂质过氧化反应的抑制作用都较小,可见苦瓜多糖具有一定的抗氧化和抑制癌细胞增殖作用.     

玛咖多糖的提取条件及体外活性研究

优化玛咖多糖的提取条件,并通过体外实验对其抗氧化活性和降血脂功效进行研究。采用超声波辅助热水浸提并结合响应面法对玛咖多糖提取条件进行优化,通过自由基清除率评价玛咖多糖的抗氧化活性,基于玛咖多糖与胆酸钠的结合能力评价其降血脂功效。在提取温度50℃,提取时间42min,超声功率220W,料液比(g/mL)1∶32的条件下,多糖提取率达到最高11.0%。将玛咖粗多糖通过离子交换柱分离得到3个多糖组分,分别为玛咖多糖1、玛咖多糖2和玛咖多糖3。其中玛咖粗多糖、玛咖多糖1和玛咖多糖2具有较强的抗氧化活性,对DPPH自由基的较佳清除率分别为83.9%、81.8%和63.7%,对羟基自由基的较佳清除率分别为73.3%、56.8%和76.7%。此外,玛咖多糖3在体外对牛磺胆酸钠和甘氨胆酸钠的结合率分别为49.1%和32.3%。研究表明,玛咖粗多糖、玛咖多糖1和玛咖多糖2具有较好的抗氧化活性,玛咖多糖3具有一定的降血脂功效。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

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.     

Jane Eyre——A Feminist In The 19th Century

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-