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ZHANG WenlingDepartment of Mathematics Physics National Natural Science Foundation of China Beijing China 《中国科学A辑(英文版)》2004,(6)
We use qualitative analysis and numerical simulation to study peaked traveling wave solutions of CH-γ and CH equations. General expressions of peakon and periodic cusp wave solutions are obtained. Some previous results become our special cases. 相似文献
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杂多酸在活性炭上的固载化Ⅲ.活性炭在酸性介质中对钨硅杂多酸(SiW_(12))的吸附 总被引:1,自引:0,他引:1
在氢离子浓度均为3mol/L的硫酸,盐酸,磷酸,醋酸水溶液中和冰醋酸中研究了具有Keggin结构的硅钨杂多酸(SiW_(12))在不同来源活性炭上的吸附作用。各活性炭对SiW_(12)吸附等温线的形式是不相同的,吸附剂载体的微孔结构以及杂多酸的溶剂化起着重要的作用。并且在无机酸介质中,杂多酸的吸附量比在水溶液中成规律性地增加,且与酸强度成正比关系。在有机酸介质中,吸附作用比较复杂。根据所得结果,提出了在酸性介质中杂多酸在活性炭表面的吸附模型。 相似文献
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新老混凝土的粘结机理和测试方法研究综述 总被引:11,自引:0,他引:11
就影响新老砼粘结性能的主要因素,新老砼结合面处理方法,修补材料的选择和应用,粘结剂的种类,新老砼粘结性能试验方法,新老砼粘结机理五个方面的问题进行了论述。依实际工程砼结构修补加固统计结果,指出实际砼修补量最大的是道路和桥梁,提出了关于道路、桥梁、汽车库、飞机场等交通设施,砼修补需进一步研究的问题。 相似文献
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A rapid and simple method using capillary electrophoresis (CE) with chemiluminescence (CL) detection was developed for the determination of levodopa. This method was based on enhance effect of levodopa on the CL reaction between luminol and potassium hexacyanoferrate(III) (K3[Fe(CN)6]) in alkaline aqueous solution. CL detection employed a lab-built reaction flow cell and a photon counter. The optimized conditions for the CL detection were 1.0 × 10−5 M luminol added to the CE running buffer and 5.0 × 10−5 M K3[Fe(CN)6] in 0.6 M NaOH solution introduced postcolumn. Under the optimal conditions, a linear range from 5.0 × 10−8 to 2.5 × 10−6 M (r = 9991), and a detection limit of 2.0 × 10−8 M (signal/noise = 3) for levodopa were achieved. The precision (R.S.D.) on peak area (at 5.0 × 10−7 M of levodopa, n = 11) was 4.1%. The applicability of the method for the analysis of pharmaceutical and human plasma samples was examined. 相似文献
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Indirect detection of paracetamol was accomplished using a capillary electrophoresis-chemiluminescence (CE-CL) detection system, which was based on its inhibitory effect on a luminol-potassium hexacyanoferrate(III) (K3[Fe(CN)6]) CL reaction. Paracetamol migrated in the separation capillary, where it mixed with luminol included in the running buffer. The separation capillary outlet was inserted into the reaction capillary to reach the detection window. A four-way plexiglass joint held the separation capillary and the reaction capillary in place. K3[Fe(CN)6] solution was siphoned into a tee and flowed down to the detection window. CL was observed at the tip of the separation capillary outlet. The CL reaction of K3[Fe(CN)6] oxidized luminol was employed to provide the high and constant background. Since paracetamol inhibits the CL reaction, an inverted paracetamol peak can be detected, and the degree of CL suppression is proportional to the paracetamol concentration. Maximum CL signal was observed with an electrophoretic buffer of 30 mM sodium borate (pH 9.4) containing 0.5 mM luminol and an oxidizer solution of 0.8 mM K3[Fe(CN)6] in 100 mM NaOH solution. Under the optimal conditions, a linear range from 6.6 × 10−10 to 6.6 × 10−8 M (r = 0.9999), and a detection limit of 5.6 × 10−10 M (signal-to-noise ratio = 3) for paracetamol were achieved. The relative standard deviation (R.S.D.) of the peak area for 5.0 × 10−9 M of paracetamol (n = 11) was 2.9%. The applicability of the method for the analysis of pharmaceutical and biological samples was examined. 相似文献
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本文采用高温分解和焙烧硝酸盐的方法合成了一系列Ni基六铝酸盐催化剂BaNiyAl12-yO19-δ (y=0.1、0.3、0.6、0.9和1.0),并对它们在甲烷部分氧化制合成气反应中的催化性能、催化剂表面积碳及活性组分Ni流失等情况进行了考察。结果表明,该催化剂对甲烷部分氧化制合成气反应具有较好的催化活性,在850 ℃,甲烷转化率和CO选择性分别可达92%和95%。并且催化剂BaNiyAl12-yO19-δ (y=0.3)在100小时的POM反应后,催化剂表面积碳很少,积碳量仅为样品净重的0.8%,特别是100小时反应后,催化剂表面活性组分Ni没有发生流失。这种低积碳量和无活性组分Ni流失与催化剂结构中Ni与相邻原子间的强相互作用有关。 相似文献
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Design and application of 60mer oligonucleotide microarray in SARS coronavirus detection 总被引:6,自引:0,他引:6
SHI Rong MA Wenli WU Qinghua ZHANG Bao SONG Yanbin GUO Qiuye XIAO Weiwei WANG Yan & ZHENG Wenling . Institute of Molecular Biology First Military Medical University Guangzhou China . Department of Medical Research Guangzhou Liu Hua Qiao Hospital Guangzhou China Correspondence should be addressed to Ma Wenli 《科学通报(英文版)》2003,48(12):1165-1169
In April 2003, a novel coronavirus[1,2] which was associated with cases of Severe Acute Respiratory Syn-drome (SARS) was first isolated and sequenced in Canada. The genome of SARS coronavirus (SARS-CoV) is 29727[3] nucleotides in length and has 11 known open reading frames (ORFs). Although the genome organiza-tion of this virus is similar to that of other coronaviruses, phylogenetic analyses and sequence alignment show that SARS-CoV is not closely related to any of the previously ch… 相似文献