L-半胱氨酸自组装膜修饰电极对抗坏血酸的电催化氧化及其分析应用

研究了L-半胱氨酸自组装膜修饰电极(L-Cys/Au SANs)的制备方法和其电化学行为,发现该电极对抗坏血酸(AA)具有明显的电催化氧化作用,在pH 4.03的BR缓冲溶液中,AA在L-半胱氨酸自组装膜修饰电极上产生一灵敏的氧化峰,峰电流与AA浓度分别在8.0×10-7-8.0×10-6mol·L-1和4.0×10-5-4.0×10-4 mol·L-1范围内呈良好的线性关系,相关系数分别为0.997 0和0.996 7,检测限为1.6×10-7mol·L-1.该方法可用于AA的测定.     

甲氨蝶呤在Co/GC离子注入修饰超微电极上的电化学行为

甲氨蝶呤 (MTX)在 0 0 0 5mol·L-1 Tris 0 0 5mol·L-1 NaCl(pH7 12 )缓冲溶液中 ,用Co/GC离子注入修饰超微电极进行伏安测定 ,得到一良好的还原峰 ,峰电位Ep=- 0 978V(vs.SCE) .峰电流ip 与MTX的浓度在 8 0× 10 -8～ 9 6× 10 -6mol·L-1 范围内成线性关系 ,检出限为1 0× 10 -8mol·L-1 .基于此建立了测定MTX的新方法 .用于市售药片测定 ,回收率在 98 9%～10 6 2 %之间 .用线性扫描和循环伏安法研究了体系的电化学行为及电极反应机理 .实验表明 ,MTX的还原为不可逆吸附过程 ,并伴随 2个电子参与电极反应 .经扫速对催化效率的影响实验证明体系存在催化作用     

不对称草酰胺镍配合物修饰电极的制备及其对甲醛的电催化研究

研究了不对称配体氮苯甲酸氮乙二胺草酰胺镍配合物修饰电极的制备 ,用循环伏安法探讨了该修饰膜的电化学性质及其对甲醛的电催化氧化。在 0 .1mol·L-1NaOH溶液中 ,膜的循环伏安图在 0 .4V和 0 .3V处有一对准可逆的氧化还原峰 ,对应着Ni(Ⅱ ) /Ni(Ⅲ )的氧化还原反应过程 ,属一电子过程 ,实验结果还表明电荷在膜中的传递为扩散控制。实验测定了在 0 .1mol·L-1NaOH中 3种不同厚度修饰膜电极、扫速在 10～ 40 0mV/s范围内氧化还原峰的特征。当配合物表面含量是 9.4× 10 -10 mol·cm-2 时 ,膜中电荷的扩散系数Dct是 1.1× 10 -12 cm2 ·s-1。该修饰膜对甲醛有良好的电催化作用且稳定性高 ,连续催化 2h以上峰电流才开始下降。常温下将修饰电极置于空气中放置 10d其催化性能也不发生变化     

聚L-苯丙氨酸修饰电极测定对乙酰氨基酚

采用循环伏安法制备了聚L-苯丙氨酸薄膜修饰玻碳电极,研究了对乙酰氨基酚在该修饰电极上的电化学行为,建立了循环伏安法测定对乙酰氨基酚的新方法.研究发现:在pH 7.0的磷酸盐缓冲溶液中,聚L-苯丙氨修饰电极对对乙酰氨基酚存在灵敏的氧化作用,氧化峰电位负移50 mV.对乙酰氨基酚的浓度在2.0×10-5~2.0×10-4mol.L-1和8.0×10-7~2.0×10-5mol.L-1范围内与其峰电流呈良好的线性关系,检出限为5.0×10-7mol.L-1.对1.0×10-5mol.L-1对乙酰氨基酚平行测定5次,相对标准偏差为1.6%.该法可用于药品中对乙酰氨基酚的测定,结果满意.     

二甲基亚砜中Co2+、Ni2+和Fe2+的电化学行为

研究了二甲基亚砜中Co2+、Ni2+和Fe2+电化学行为. 在1.00×10-2 mol·L-1CoCl2-0.1 mol·L-1LiClO4-DMSO、1.00×10-2mol·L-1NiCl2-0.1 mol·L-1LiClO4-DMSO和1.00×10-2 mol·L-1FeCl2-0.1 mol·L-1LiClO4-DMSO体系中利用循环伏安法和计时电流法测定3种体系中Co2+、Ni2+和Fe2+的扩散系数DO. 结果在304 K时,循环伏安法测定3种体系中Co2+、Ni2+和Fe2+的扩散系数DO分别为1.31×10-5、1.27×10-5和1.59×10-5 cm2*s-1;在299 K时,计时电流法测定Co2+、Ni2+和Fe2+的扩散系数DO分别为1.01×10-5、1.43×10-5和1.39×10-5 cm2·s-1.     

抗癌药物甲氨蝶呤在Nafion修饰电极上的伏安法研究

本文研究了Nafion修饰玻碳电极对抗癌药物甲氨蝶呤的阴极溶出伏安法特性,探讨了其电极反应机理,建立了测定甲氨蝶呤的方法.用本方法.甲氨蝶呤的最低检测限为2.2×10~(-8)mol·L~(-1),在4.4×10~(-8)～2.5×10~(-6)mol·L~(-1)之间,峰高与浓度呈良好的线性关系,连续测定十次,其相对标准偏差为1.5%.对样品进行分析,获得了满意的结果.     

邻菲罗啉的电化学性质研究

0.5 mol·L-1的一氯乙酸和0.1 g·L-1的十二烷基磺酸钠溶液中,邻菲啰啉有一灵敏极谱峰,其峰电位是-0.75 V(vs.SCE).峰电流与邻菲啰啉的浓度在4.0×10-7～3.8×10-5mol·L-1范围内呈线性关系(r=0.998 5),检测下限为2.0×10-7mol·L-1.利用线性扫描极谱法和循环伏安法研究了邻菲啰啉的电化学性质.     

甲氨蝶呤的电化学行为及应用的研究

在 0 .1mol·L- 1NH3 NH4 Cl (pH 9.8)缓冲溶液中 ,甲氨蝶呤在单扫示波极谱上有一灵敏的导数极谱峰 ,峰电位Ep=- 0 .83V(vs .SCE) .峰电流ip 与甲氨蝶呤的浓度在 5 .4× 10 - 8～ 6.5× 10 - 6 mol·L- 1范围内成线性关系 ,检出限为 4 .33× 10 - 8mol·L- 1.基于此建立了单扫示波极谱测定甲氨蝶呤的新方法 ,用于市售药片的测定 ,回收率在 92 .9%～ 10 6.8%之间 ,结果令人满意 .用线性扫描和循环伏安法研究了体系的电化学行为及电极反应机理 ,实验表明 ,甲氨蝶呤的还原属于具有吸附性的准可逆过程 ,并伴随 2个电子、2个氢离子参与电极反应 .     

抗癌药物甲氨蝶呤在Nafion修饰电极上的伏安法研究

本文研究了 Nafion 修饰玻碳电极对抗癌药物甲氨蝶呤的阴极溶出伏安法特性,探讨了其电极反应机理,建立了测定甲氨蝶呤的方法。用本方法.甲氨蝶呤的最低检测限为2.2×10~(-8)mol·L~(-1),在4.4×10~(-8)～2.5×10~(-6)mol·L~(-1)之间,峰高与浓度呈良好的线性关系,连续测定十次,其相对标准偏差为1.5%。对样品进行分析,获得了满意的结果。     

一种新的PVC膜铬(VI)离子选择电极的研制及应用

以自制的硝基酞菁钯研制了PVC膜铬(VI)离子选择电极.在B R缓冲液(pH为1.97)中,电极在铬(VI)离子浓度为1.0×10-5mol·L-1～1.0×10-2mol·L-1范围内呈良好的线性关系,检测限为2.95×10-6mol·L-1.实验测得的电极响应斜率与混合价态离子斜率的理论推断值相符.在选定的条件下,大部分的离子对铬(VI)的测定基本无干扰,电极用于电镀废水铬(VI)离子的测定,结果令人满意.     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.     

On Tragic Consciousness In The Works By Ernest Hemingway

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.