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1.
介绍了NaOH溶液中(pH>11)利用胆绿素的阳极波的极谱分析方法,研究发现胆绿素在-0.40V(VS.SCE)左右产生一灵敏、稳定的极谱阳极波,该波的二阶导数与胆绿素溶液的浓发在2×l0 ̄(-7)~1.8×l0 ̄(-6)mol·L ̄(-1)范围内成线性关系,其检测限为8×l0(-8)mol·L ̄(-1),并且在胆红素或0.02mg·L ̄(-1)白蛋白共存时无干扰,可用于胆绿素的测定,并对胆绿素的极谱阴极波和循环伏安图进行了研究,考察了胆绿素在-0.40V(VS.SCE)处的可逆波和-0.98V(VS.SCE)处的过氧化氢催化波的性质,对胆绿素的电化学反应提出了可能的机理。  相似文献   

2.
阐述了应用分光光度法测定胆汁中微量钙的方法.方法基于在强碱性溶液中钙与钙黄绿 素(荧光素-3,3’-双甲氨基-二乙酸)间形成一种配合物,于钙黄绿素溶液中加入钙后在波长509nm 处测量钙黄绿素溶液吸光度减少值.方法简便、快速,测定范围为 0.2~2.5μm Ca/mL,相对标 准偏差为±2%左右.胆汁中的镁、锌和胆绿素不干扰测定.本法可用于临床分析中钙的测定.  相似文献   

3.
胆绿素衍生物的制备与纯化   总被引:1,自引:1,他引:0  
从新鲜猪血中提取血红蛋白,以氧合血红蛋白为原料,通过偶联氧化制备胆绿素二盐酸盐(BV.2HCl)和胆绿素二甲酯(BVED),用溶剂萃取和相液相层析技术对产物进行确证和表征。对分离与纯化过程中由于BV的不稳定性所造成的困难问题及其解决办法进行了讨论。  相似文献   

4.
猪肾胆绿素还原酶活性基因的修饰   总被引:1,自引:0,他引:1  
报道采用专一性试剂DTNB、NEM、磷酸吡哆醛以及2,3-丁二酮对胆素还原酶活性进行修饰,当这几种试剂分别与该反应后,酶活性性大幅度降低;而当预先加入NADPH或胆绿素、酶活性明显受到保护,这些结果表明,半胱氨酸、赖氨酸和精氨酸残基与该酶同NADPH和胆绿素结合、以及胆绿素还原成胆红素的反应有关,是该酶活性必需的基因。  相似文献   

5.
用极谱法和分光光度法对影响胆红素,胆绿素稳定性的各种因素进行了考察比较。揭示了影响它们稳定性的主要外部因素-氧,酸度和某些金属离子,针对这些影响因素,探索了胆红素,胆绿素的稳定化途径和稳定化机制。  相似文献   

6.
从结构振动波的角度探讨了无限长输液管中结构振动特性,结果表明,在无阻尼条件下,弯曲波可分成两组,一组为沿正、反方向的传播波,另一组为沿正、反方向的衰减波.在有阻尼条件下,弯曲传播波变为沿正、反方向的远场波,同时衰减波成为正、反方向的近场波.研究了它们随阻尼、流速和频率参数的变化规律  相似文献   

7.
蛇形多向不规则波造波机波浪产生方法及特性   总被引:4,自引:0,他引:4  
介绍了自行研制的蛇形多向不规则波造波机系统.造波机宽28m,由70块高0.9m、宽0.4m的造波板组成.在此基础上论述了分段式造波机产生波浪的原理及方法,并对其产生的斜向和多向不规则波的波浪统计特性以及波浪的频谱和方向分布进行了试验研究.结果表明,研制的造波机各项性能达到了预期的指标,可产生较理想的单向和多向不规则波.  相似文献   

8.
研制了单片机程序控制波动演示仪,给出硬件电路设计和软件程序设计.波动演示仪的功能包括:波的向右运动演示。波的向左运动演示.静态波形演示。波的传播中同相点及反相点演示,单一质点振动演示等.各种波形的运动速度可以调节,并可单步执行.  相似文献   

9.
豚鼠离体小肠电活动与机械收缩   总被引:3,自引:0,他引:3  
以小肠电活动和环肌张力、纵肌张力为指标,用同步记录的方法研究了豚鼠离体小肠电活动与环肌张力、纵肌张力之间的关系,结果表明:(1)豚鼠离体小肠的电活动包括慢波与峰波;(2)豚鼠离体小肠始终存在着节律性张力活动,其环肌收缩与纵肌收缩的关系表现为拮抗收缩、共同收缩、交互抑制等形式;(3)峰波可增加收缩力,峰波的个数、振幅与小肠张力呈正变关系,尤其与环肌收缩的对应关系更为显著.(4)慢波可触发收缩,尤其是纵肌收缩.在没有峰波仅有慢波时,亦可有收缩活动甚至活跃的收缩活动.  相似文献   

10.
研究了胆素溶液及经过热处理和添加H2O2,Zn^2+或表面活性剂等之后的荧光变化,发现上述处理均使胆绿素溶液的荧光强度增大,荧光增强程度因处理方法不同而异。进一步对胆绿素的碱性水溶液的不同处理方法即热处理,热处理并加Zn^2+热处理后加Zn^2+再加表面活性剂等进行时间扫描灾光动力学研究,获得了上述不同处理形式的胆素溶液的荧光强度随时间变化的规律,新配制胆绿素碱溶液经热处理,热处理后形式的胆绿素溶  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.
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.
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   

16.
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   

17.
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   

18.
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   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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