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1.
采用Ar^+离子溅射方法将300nm SnO2薄膜沉积在Si片上,分别对膜层进行60keV,5×10^16cm^-2Mg^+离子注入和100kdV,6×10^16cm^-1Nb^+离子注入,对未注入,Mg^+离子注入,Nb^+离子注入3种薄膜进行500℃,4h退火处理.  相似文献   

2.
用TBD-Span80-二甲苯乳状液膜体系研究了La^3+的迁移行为,确定了完全、快速迁移La^3+的条件。在该条件下,能够使La^3+从常见过渡元素Fe^3+、Co^2+、Ni^2+、Cu^2+、Cd^2+、Mn^2+、Zn^2+等离子的混合液中得到完全分离。  相似文献   

3.
微波辐射下壳聚糖的化学改性及其应用研究(Ⅱ)   总被引:7,自引:3,他引:4  
在稀醋酸溶液中,微波辐射下壳聚糖与Cu^2+反应制备了壳聚糖Cu^2+配合物,然后将制得的配合物与环氧氯丙烷在微波辐射下再进行交联反应后,用稀酸除去Cu^2+,合成了具有Cu^2+离子孔穴的交联壳聚糖树脂。考察了该树脂对Cu^2+、Ni^2+、Co^2+的吸附性能。实验表明,使用微波辐射模板法制备具有Cu^2+离子孔穴的交联壳聚糖树脂,能大大缩短反应时间;制备的树脂在酸性条件下不会发生软化和溶解,  相似文献   

4.
Hg^2+对玉米幼苗膜脂过氧化防御系统的影响   总被引:3,自引:0,他引:3  
用控制营养液Hg^2+量(0mg/L,0.3mg/L,0.6mg/L)的方法培养玉米幼苗,得到3种Hg^2+水平的玉米幼苗叶片为材料,研究不同Hg^2+水平对玉米幼叶膜透性及其膜脂过氧化防御系统的影响,结果表明,经Hg^2+处理的玉米幼叶膜相对透性和丙二醛含量显著上升;SOD活性呈“先上升后下降”趋势,而POD,CAT活性呈明显下降趋势。且0.6mg/LHg^2+处理的各项指标变化幅度均大于0.3  相似文献   

5.
复合型纳滤膜的制备及表征   总被引:12,自引:0,他引:12  
在聚砜基膜上用界面聚合法制备了两种复合型纳滤膜PA01和PA02。在0.3MPa下,PA01膜对MgSO4溶液和FeCl3溶液的脱直 96.0%和78.0%,水通量分别为8.5(L.m^-2.h^-1)和7.9(L.m^-2.h^-1);PA02膜对MgSO4ipwkiyw (2.0g.L^-1)和CaCl溶液(0.5g.L^-1)的脱盐率分别为98.0%和88.8%,水通量分别为1.0(L。m^  相似文献   

6.
^4^5Ca跨膜流动测定技术用于中药钙拮抗作用的研究   总被引:1,自引:2,他引:1  
应用45Ca跨膜流动测定研究的钙拮抗剂verapamil,中药西红花(Crocus SativusL.),“地奥心血康”(DAXXK),川红花及银杏叶等对大鼠主动脉45Ca跨膜内流的作用,以确定其对细胞膜Ca^2^+通道影响。实验结果表明:西红花,川红花,DAXXK对平滑肌细胞膜上电压依赖Ca^2^+通道(PDC)和受体操纵Ca^2^+通道(ROC)都有阻滞作用,并以西红花的阻滞作用最强;而银杏叶  相似文献   

7.
两亲性卟啉-紫精化合物具有分子同光电子转移体系。用LB膜技术在透明导电玻璃基片上制备成分子排列规则的超薄膜材料,并用两种光电池(导电玻璃/LB膜/I3,I/导电玻璃,导电玻璃/LB膜/Hg探针)测量了LB膜的光量子产率和光电开关性能。作为分子光电二极 管,其最大光最子产率为3.17×10^-^6,光电开关的响应起始时间和驰豫时间分别约为0.2和0.3S,并具有较好的光电响应寿命。  相似文献   

8.
水合五氧化二锑的合成及其对Sc^3+吸附性能的研究   总被引:7,自引:2,他引:7  
利用所合成的水合五氧化二锑,研究了它对Sc^3=及其他离子的吸附性能。结果表明,所合成的HAP在酸性条件下不仅能吸附Na^+,而且对SC^3+也有很好的吸附性能。此外,还测定了所合成的HAP在不同烘烤温度下的晶胞参数及对Sc^3+的吸附交换性能。实验表明经250℃烘烤的HAP具有对Sc^3+最大的吸附交换容量。  相似文献   

9.
研究了单(Si^+)双(Si^+/As^+)离子注入半绝缘砷化镓电激活的均匀性,结果表明,LECSi-GaAs衬底中深电子陷阱能级均匀性分布好坏,对注入层电激活性有一定影响,当SI-GaAs中碳含量小于5*10^15cm^-3时,对注入层电激活影响不大,采用多重能量Si^+注入,可改善栽流子纵向分布的均匀性,采用Si^+/As^+双离子注入可改善LEC SI-GaAs衬底中EL2横向不均匀分布对电  相似文献   

10.
纯化小麦液泡膜H^+-ATPase,测定了纯化的小麦液泡膜H^+-ATPase受Mg^2+和Ca^2+双重激活的特性及两种激活状态下酶的特性,Mg^2+激活时酶水解活性受DCCD的抑制,受旨酰丝氨酸(PS)影响明显,ATP水解和泵质子活性相偶联,而在Ca^2+激活时酶水解活性不受DCCD抑制,受PS影响微弱,Ca^2+激活时ATP水解与泵质子活性解偶联,Mg^2+和Ca^2+对小麦液泡膜H^+-A  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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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