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1.
用循环伏安法描述了三元络合物Cu2(EGTB)(bpy)Cl4·8H2O(以下以Cu2(Ⅱ)L代)与二氧的反应.在含0.1mol·dm-3四丁基高氯酸铵的DMF溶液中加入Cu2L,使得O2/O2-的可逆伏安图发生变化对。O2的Ip.c增大,并在比O2还原电势更正的地方产生一新峰.当[Cu2L]大约为2.4mmol·dm-3时,仅存在唯—一个峰且基本不变.结果表明Cu2L能与O2-反应产生O2,有良好的超氧化物歧化酶性质.  相似文献   

2.
厦门西海域二氧化碳体系   总被引:1,自引:0,他引:1  
由pH和碱度测定值计算了厦门西海域海水中CO_2体系及CaCO_3的饱和度,结果表明ΣCO_2、和CO_[2(.T)]的浓度分别是1.96~2.30mmol/L、1.82~2.16mmol/L、0.10~0.12mmol/L和0.017~0.026mmol/L。CaCO_3的饱和度是150.1%~208.5%。讨论了叶绿素a对ΣCO_2和CO_(2(T))的影响以及CaCO_3饱和度与Alk的关系。  相似文献   

3.
在50、100和200mmol/l下,研究了NaCI、Na2SO4和Na2CO3对小麦高生长、生物量生长、脯氨酸及Na+,K+含量的影响。NaCI处理使高度下降8.8%~35.4%、而Na2SO4和Na2CO3分别为8.8%~77.9%和53.1%~100.0%。NaCI处理使鲜重和干重分别降低14.3%~42.9%和6.1%~36.7%,而Na2SO4处理分别为14.3%~64.3%和7.2%~58.9%,Na2CO3处理分别为50.0%~74.1%和48.3%~72.8%。在NaCI、Na2SO4和Na2CO3处理下,脯氨酸含量分别增加0.0%~66.7%、0.0%~33.3%和66.7%~100.0%。Na+/K+分别提高2.5~11.9、3.6~114.1和35.1~156.6倍。结果表明:Na2CO3的胁迫比Na2SO4强,而Na2SO4的胁迫影响又比NaCl强  相似文献   

4.
葡萄糖-BrO3--Mn2+-H2SO4-丙酮体系的振荡反应   总被引:1,自引:0,他引:1       下载免费PDF全文
以葡萄糖为有机底物,与-BrO3--Mn2+-H2SO4-丙酮组成振荡反应体系,在恒温条件下进行振荡反应。结果表明:反应有诱导期,体系电导(L)不随时间(t)变化;振荡周期,L随t发生周期变化,溶液颜色在粉红色与无色之间交替变化,有典型的振荡波型。诱导期及振荡周期反应的表观活化能分别为84.275kJ/mol和98.153kJ/mol。体系振荡反应物浓度范围[葡萄糖]0.01~0.02mol/L,[BrO3-]0.03~0.045mol/L,[Mn2+]0.06~0.08mol/L,[丙酮]0.27~0.30mol/L,[H2SO4]0.8~1.2mol/L。振荡反应有Br2产生,Br2准一级消耗速率常数kBr2=1.6×10-5S-。对温度、反应物浓度、丙酮、Mn2+、Cl-、底物对振荡反应的影响作了探讨。  相似文献   

5.
盐生杜氏藻Dunaliella salina的生物学特性与培养研究   总被引:7,自引:0,他引:7  
盐生杜兵藻富含β-胡萝卜素和蛋白质,适宜在高纬度、光照强的各种咸水环境中生长,对它的生物学特性和培养条件进行了研究,发现适宜于盐生杜氏藻生长的培养基主要成分为:2mol/LNaCl,5mmol/LKNO3,6.5mmol/LNaHCO3,5mmol/LMgSor,0.3mmol/LKH2PO4。  相似文献   

6.
以过硫酸钾为引发剂,研究了丙烯酰胺与玉米淀粉接枝共聚的反应规律,实验结果表明:当[K_2S_2O_8]=-100mmol/L、[AM]=0.422mmol/L,在60℃反应3h,接枝率、接枝效率、单体转化率及产率都很高。  相似文献   

7.
CaCl2和Ca(NO3)2对降低玉米幼苗质膜透性的作用   总被引:4,自引:0,他引:4  
以玉米为实验材料,分别用150mmol/L,150mmol/L,NaCl+15mmol/L CaCl2及150mmol/LNaCl=15mmol/LCa(NO3)2的1/2浓度Hoagland溶液连续处理5天后,分别测定MDA含量,质膜透性,植物鲜重,植物干重及植物体内Na^+含量。  相似文献   

8.
单核和双核Cu(Ⅱ)—Schiff碱配合物的合成,晶体结构?…   总被引:1,自引:1,他引:0  
报导了4个Schiff碱配体的Cu(Ⅱ)配合物[(Cu(Ⅱ)(L1)]ClO4(1),[Cu(Ⅱ)(L2)(H2O)]BF4(2),Cu(Ⅱ)2(L3)2(Cl)2(3)和[Cu(Ⅱ)2(L4)(OH)(H2O)](BF4)2(4)的合成和晶体结构以及它们的电子光谱特性,4个配体由醛与胺综合而得,产物未经分离,直接用于合成配合物,以配合物产率计,综合反应的产率不低于60%。通过比较它们的晶体结构参  相似文献   

9.
用人工配制高浓度有机废水分别研究了Cl-和SO2-4对厌氧生物废水处理的抑制作用和抑制阈值.在全混流厌氧恒化器和上流式厌氧污泥床(UASB)反应器中分别得到了对厌氧消化基本无抑制作用(全混流恒化器:Cl-<4.5g/L,SO2-4<1.8g/L;UASB:Cl-<7.2g/L,SO2-4<3.0g/L);轻度抑制(全混流恒化器:Cl-=4.5~6.0g/L,SO2-4=1.8~3.3g/L;UASB:Cl-=7.2~8.2g/L,SO2-4=3.0~4.1g/L);中度抑制(全混流恒化器:Cl-=6.0~13.8g/L,SO2-4=3.3~6.5g/L;UASB:Cl-=8.2~10.0g/L,SO2-4=4.1~6.0g/L)和重度抑制(全混流恒化器:Cl->13.8g/L,SO2-4>6.5g/L;UASB:Cl->10.0g/L,SO2-4>6.0g/L)的不同Cl-和SO2-4浓度范围.  相似文献   

10.
不同程度中碱性复合盐对向日葵生长的影响   总被引:16,自引:1,他引:15  
模拟天然盐碱生态条件,将NaCl、Na2SO4、NaHCO2和Na2CO3等4种盐按不同比例混合成30种盐碱强度各不相同的混合盐溶液(浓度为50-250mmol/L,pH值为7.12-10.72),对向日葵苗进行盐碱混合胁处理。结果表明:(1)无论PH高低只要总盐浓度不超过100mol/L向日葵即可全部存活,但如果总盐浓度超过100mmol/L,同时PH值高于9.75,盐的浓度和PH值二者之中行休  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.
<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   

19.
20.
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has  相似文献   

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