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1.
探讨了1-硝基蒽醌(1-NO_2AQ)和1-氨基蒽醌(1-NH_2AQ)同时测定和分别测定的色谱条件,提出了在Shim-packCLSS-SIL色谱柱上,以正庚烷-1,4二氧六环-乙酸乙酯(65:35:5(V/V)为流动相,流量为1.5ml/min,柱温40℃,以分光光度检测器于254nm处检测时,4min内使1-NO_2AQ与1-NH_2AQ分离;5min使1-NH_2AQ与杂质分离;7min可使1-NO_2AQ与杂质分离的高效液相色谱分析法。其绝对检出下限1-NO_2AQ为0.012μg,1-NH_2AQ为0.026μg,变异系数分别为1.1%和0.96%,回收率分别为99.7%和100.2%。  相似文献   

2.
用真空葛氏摆研究了CuZnAl形状记忆合金平衡状态下的内耗。在室温至500℃ 温度范围内,观测到两个弛豫型内耗峰,峰温分别为240℃和340℃(J≈1,7Hz). 通过改变频率测得240℃峰的弛豫激活能为113kJ/mol,345℃峰的弛豫激活能 为176kJ/mol.计算了两个峰的τ0值,确定345℃峰为α相中Zener弛豫 峰,240℃峰则是由β有序相内反向畴界处某种点缺陷运动所产生。  相似文献   

3.
研究了BPH340冷轧汽车钢板的内耗谱,得到了原始态、变形态及在不同温度下退火、淬火试样的Q^-1-t曲线,以及各种因素对内耗谱的影响,说明生产汽车钢的内耗谱具有其特殊性和复杂性。  相似文献   

4.
在热重分析系统上进行磁热重分析(MTGA),测量非晶FeSiB合金升温过程的比饱和磁化强度随温度变化σ-t曲线及(dσ/dt)-t曲线,它比DSC分析能更加明显的区分晶化过程的各个阶段,结果表明,样品升温过程经历了6个阶段的变化;并且发现,在晶化温度tx以下约150℃温区内等温退火的样品,居里温度tc随退火温度ta增大而升高,在430℃附近tc上升出现拐点。(dσ/dt)-t曲线的极小温度峰温tm  相似文献   

5.
利用液态内耗仪研究了聚醋酸乙烯酯(PVAc)在其玻璃化转变温度(Tg)及其以上温度区域的力学弛豫行为.结果表明:PVAc内耗与温度的关系曲线上存在α和α′ 2个弛豫型内耗峰,α峰与PVAc的玻璃化转变有关,α′峰则对应于一种液/液转变,且两者的弛豫时间均满足Vogel Fulcher Tamman关系;在PVAc熔体内耗与频率的关系曲线上,交叉温度TB≈387 K处的α′峰的弛豫时间、弛豫强度和分布参数均出现了一个转折,这是由于降温过程中TB至Tg之间分子耦合作用显著增强的结果.  相似文献   

6.
对淬火及淬火后变形Fe-P-N合金在-50℃~350℃温度区的内耗进行了测量,并用TEM观察、分析了合金中的第二相.结果表明,在N的质量分数不超过0.003%和P的质量分数小于0.064%的实验条件下,合金的SKK峰与Snoek峰的峰高比(hSKK/hSs)和Cp-2/3呈线性关系;在Fe-P合金固溶体区中有FeP化合物存在.  相似文献   

7.
本文采用单项指标(T,Q,C)复合指标(T-Q,T-C,C-Q)和综合指标(T-Q-C),相应运用表格法,工程管理曲线法和三维图形法,提出完整实用的公路工程项目实施状态分析方法,即:实时分析→状态预测→未时分析,以满足公路工程项目管理的实际需要。  相似文献   

8.
研究了4-(8-氨基喹啉-5-偶氮)-苯横酸钠(SAOABS)的极谱行为。在0.02ml/LNH_3·H_2O-0.36mol/LNH_4Cl的缓冲溶液中,SAQABS产生两个明晰的阴极化极谱波,其二次导数波的峰电位分别为-0.52V和-1.30V(Vs.SCE)。用SAQABS的第一个波作为定量分析的基础,其线性范围为1.0×10 ̄(-6)~8.0×10 ̄(-5)mol/L。氧不干扰SAQABS的测定。还研究了SAQABS的电极过程及反应机理。  相似文献   

9.
合成了Eu(TTA)4Rh6G三元配合物(TTA:2-噻吩甲酰三氟丙酮;Rh6G:Rhodamine6G).对该配合物作了元素分析,DTA-TG分析和电导分析,测定了它的IR和UV吸收光谱,确定其化学组成为Eu:TTA:Rh6G=1:4:1,为离子缔合型.它的不同有机溶剂的溶液,在365nmUV灯照射下均能发出较强的荧光.其甲醇溶液和固态荧光光谱的最大发射峰分别为560.5nm和627.5nm.  相似文献   

10.
从广东省花都市产银环蛇(Bungarusmulticintus)蛇毒纯化得到两个K-神经毒素(K-NT):Ⅵ2d峰及Ⅷ1b峰。两者的分子量均为6500,等电聚焦PI值均为9.1。Ⅵ2d峰N端部分43个氨基酸顺序与台湾姐环蛇的K-BGT完全一致,后者是当前唯一可用于神经元烟碱乙酰胆碱受体分型的毒素探针。至此,从中国大陆产的银环蛇毒中找到K-NT家族中3个成员即:K-BGT、K_2-BGT及K_3-BGT.  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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