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1.
工艺参数对碳纳米管定向薄膜生长的影响   总被引:1,自引:0,他引:1  
为了生长出高质量的定向碳纳米管薄膜 ,研究了反应时间、反应温度等工艺参数对薄膜生长的影响。试验采用二甲苯为碳源 ,二茂铁为催化剂 ,在石英基底上催化裂解生长碳纳米管定向薄膜。通过扫描电子显微镜 (SEM)和透射电子显微镜 (TEM)观察表明 ,得到的薄膜是由定向性良好的多壁碳纳米管 (MWNTs)组成 ,管径为 2 0~ 5 0 nm。反应时间对定向生长的碳纳米管长度有决定性影响 ;随反应时间的增长 ,定向性更好。同时 ,较适合碳纳米管薄膜定向生长的反应温度区间为 10 5 3~ 1113K。而反应温度和反应时间对薄膜中碳纳米管的直径无明显影响。  相似文献   

2.
用浮动催化裂解法制取单壁碳纳米管   总被引:1,自引:0,他引:1  
为寻找一种可以批量制备高质量、高产率单壁碳纳米管的方法 ,对浮动催化裂解碳氢化合物法制取单壁碳纳米管进行了研究。实验采用苯为碳源 ,二茂铁为催化剂 ,氢气为载气 ,噻吩为添加剂。采用扫描电镜、透射电镜、高分辨透射电镜以及拉曼谱等方法对产物进行检测与评估 ,分析了参数对产物的影响。结果表明 ,裂解温度越高 ,越有利于单壁碳纳米管的生长 ;发现通过碳源和直接通入反应室的 H2 流量比为 1:2时 ,较利于单壁碳纳米管的生长。浮动催化裂解法制备出来的单壁碳纳米管直径约为 1nm,直径分布较均匀 ,并且可以半连续、低成本地生产  相似文献   

3.
泡沫浮选萃取法分离镉锌   总被引:1,自引:0,他引:1  
采用泡沫浮选萃取法分离溶液中的镉锌离子 .考察了溶液酸度、金属离子浓度、有机相与水相的比率 (O/A比 )、充气量、温度及时间对Cd2 /Zn2 分离的影响 .结果表明 :采用环烷酸 (皂 ) 煤油有机相 (0 .2mol·L-1) ,用自制的泡沫浮选萃取槽 ,在溶液 pH值为 4.0 ,O/A比为 1∶3,充气量为 30 0mL·min-1,浮选温度 2 0℃ ,浮选时间 1 0min ,溶液中Cd2 /Zn2 能很好的分离 (R(Cd)≥ 95 % ,R(Zn)≤ 2 % ) .该分离方法在湿法冶金、分析化学及环保处理等领域具有广泛的应用前景  相似文献   

4.
建立烟草提取物中二十八烷醇含量检测的气相色谱方法。采用毛细管色谱柱BD-17(30 m×530μm×1.0μm);FID检测器;气化室温度265℃;柱温为一级程序升温(150℃-1 min- 10℃·min-1-260℃-20 min);载气高纯氮39 mL·min-1;空气48 kPa;氢气49.5 kPa。平均回收率为99.7%(n=5),RSD为0.77%。该方法准确、灵敏、重现性好,可适用于二十八烷醇提取分离质控和含量检测。  相似文献   

5.
现有的5A分子筛吸附轻煤油正构烷烃的实验研究,吸附温度基本维持在300 ℃以上.本文考察了温度对分子筛吸附正构烷烃的影响,并通过正交实验研究了吸附最佳工艺条件组合.实验结果表明,吸附温度为210 ℃时,分子筛吸附正构烷烃的单位时间饱和吸附量最大,为11.45 g·h-1;同时采用正交实验,确定了最佳吸附工艺条件组合为温度=200 ℃,压力=0.3 MPa,空速=1.2 h-1以及氮气流量=50 mL·min-1,其单位时间饱和吸附量为14.90 g·h-1.  相似文献   

6.
催化裂解法制备螺旋状碳纳米管的实验研究   总被引:1,自引:0,他引:1  
在硅片上用直流溅射镀铁的方法制备催化剂 ,通过乙炔在 70 0°C下催化裂解制备碳纳米管 .对热解产物进行了扫描电镜观察和 X射线衍射测试 .本文通过对有氢气预处理和没有氢气预处理两种情况下催化裂解法制备的碳纳米管的形貌、管径大小等性质的研究 ,来初步揭示螺旋状碳纳米管的生长机理 .  相似文献   

7.
固定烟道气温室气体的微藻的分离及培养特性测定   总被引:8,自引:0,他引:8  
利用配置烟道气驯化含微藻的泥水混合试样,分离出对高浓度CO2条件有很强适应力的微藻ZY1,并对该藻的培养特性进行了测定·微藻ZY1属小球藻属·微藻ZY1在CO2的体积分数从10%到15%的范围内有较高生长力,在CO2的体积分数为10%时,生长最好·微藻ZY1对温度、气体流速、pH值等物理条件也有很宽的适应范围,在温度为25~30℃、流速为025~075L·min-1、pH4~6范围内,生长基本稳定·在培养条件为10%CO2、25℃、pH50时,微藻ZY1的增长率最高,CO2的固定率平均值为0397%·上述结果表...  相似文献   

8.
建立阿苯哒唑混悬剂的高效液相色谱含理测定方法 ,方法 :用RP - 8(4 2 5 0mm ,5 μm)色谱柱 ;6 2 %甲醇为流动相 ,流速 1mL·min-1;2 95nm检测 ,本品在 4~ 36 μg·mL-1呈良好线性 (r =0 9999) ,回收率为 99 12 %~10 2 81% ,RSD =1 13 % (n =9)。  相似文献   

9.
提出了一种解决燃料电池系统低温启动的策略,将氢气和空气预混合气体在燃料电池外部进行催化燃烧,然后将燃烧后的尾气通入燃料电池阴极流场和水流场以加热燃料电池系统.基于此低温启动策略,搭建了低温启动试验平台,研究了反应物混合气流量、氢气体积分数等参数对燃料电池低温启动过程的影响.试验结果表明:增大反应物混合气流量或增加氢气体积分数均能缩短低温启动时间;当流量为3L.min-1,氢气体积分数为5%时,电池内部温度在540s内上升到冰点以上温度,可以初步满足低温启动的要求.  相似文献   

10.
目的研究电池温度、氢气流量和空气流量对高温质子交换膜燃料电池的性能影响.方法通过电化学工作站测试了HT-PEM燃料电池的伏安特性和交流阻抗,利用等效电路法分解得到HT-PEM燃料电池中的欧姆阻抗和法拉第阻抗,分析电池温度、氢气流量和空气流量对燃料电池的伏安特性、欧姆阻抗和法拉第阻抗的影响.结果电池温度、氢气流量和空气流量对高温质子交换膜燃料电池性能有一定影响,温度升高和增大气体流量能够一定程度地提高高温质子交换膜燃料电池的性能.HT-PEM燃料电池的性能不会随着气体流量的增加而一直增加.结论升高温度降低了燃料电池的欧姆阻抗和法拉第阻抗;氢气流量变化和空气流量变化对欧姆阻抗和法拉第阻抗没有明显影响.  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.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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