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1.
通过引入参数,构造了一个全平面上的、含双曲函数的非齐次核函数。利用正切函数的有理分式展开,建立了最佳常数因子与正切函数高阶导数相关联的Hilbert型积分不等式。 作为应用,通过赋予参数不同的值,建立了一些有意义的特殊结果。  相似文献   
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In this paper we recast the Serret theorem about a characterization of palindromic continued fractions in the context of polynomial continued fractions. Then, using the relation between symmetric tridiagonal matrices and polynomial continued fractions we give a quick exposition of the mathematical aspect of the perfect quantum state transfer problem.  相似文献   
4.
This paper reports the development of a dual immunosensor using magnetic microcarriers (MBs) and amperometric transduction at dual screen‐printed carbon electrodes (SPdCEs) for the simultaneous determination of two biomarkers: interleukin‐13 receptor α2 (IL‐13Rα2) and E‐cadherin (E‐CDH), with both extracellular and soluble fraction; oncogenic and tumor suppressor markers, respectively, of great relevance in metastatic processes. The implemented methodology involved the formation of sandwich‐type immunocomplexes using specific capture antibodies immobilized onto carboxylic acid magnetic microbeads (HOOC‐MBs), and biotinylated detector antibodies labeled with streptavidin?horseradish peroxidase conjugates (Strep‐HRP). The amperometric detection was performed by addition of hydrogen peroxide in the presence of hydroquinone (HQ) as the redox mediator. The dual immunosensing platform provided linear calibration ranges suitable for the determination of both biomarkers in liquid and solid clinical specimens as well as excellent selectivity against other cancer biomarkers. This simple handling dual bioplatform was applied to the determination of the soluble and extracellular fraction of the target biomarkers in serum and paraffined‐embedded tissues from colorectal cancer (CRC) patients diagnosed at different tumor grade. The obtained results reveal great potential of this configuration to improve the reliability in diagnosing metastatic CRC.  相似文献   
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Crocus sativus L. belongs to the Iridaceae family and it is commonly known as saffron. The different cultures together with the geoclimatic characteristics of the territory determine a different chemical composition that characterizes the final product. This is why a complete knowledge of this product is fundamental, from which more than 150 chemical compounds have been extracted from, but only about one third of them have been identified. The chemical composition of saffron has been studied in relation to its efficacy in coping with neurodegenerative retinal diseases. Accordingly, experimental results provide evidence of a strict correlation between chemical composition and neuroprotective capacity. We found that saffron’s ability to cope with retinal neurodegeneration is related to: (1) the presence of specific crocins and (2) the contribution of other saffron components. We summarize previous evidence and provide original data showing that results obtained both “in vivo” and “in vitro” lead to the same conclusion.  相似文献   
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从NaOH试剂浓度、反应温度与反应时间三个方面,对钡离子沉淀法提取不同温度段收集的生物油馏分中的酚类物质进行了实验研究,并利用气相色谱-质谱联用仪(GC-MS)对提取效果进行了分析。实验结果表明,钡离子沉淀法对愈创木酚类物质的提取效果较为突出,且NaOH浓度(1.0-6.0mol/L)、反应温度(30-50℃)与反应时间(10-40min)对愈创木酚的提取率影响较大。在NaOH浓度为5.5mol/L、反应温度为35℃、反应时间为20min时,提取率达到最大,其中,三个温度段收集的生物油即低温水相馏分、低温油相馏分与高温馏分中的愈创木酚提取率分别为34.1%、33.8%和33.5%。  相似文献   
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本文制备了一系列不同色浆质量分数的水性聚氨酯涂料,并将其喷涂在汽车仪表板聚氯乙烯(PVC)表皮的背面形成复合材料。 用旋转流变仪表征了涂料的粘度以评价其喷涂性能;用差示扫描量热仪表征了材料的玻璃化转变温度(Tg);利用万能材料试验机表征了材料在-30 ℃条件下的拉伸性能及抗撕裂性能;用动态热机械分析仪表征了材料的损耗比随温度的变化。 结果表明:不同色浆质量分数的涂料都能喷涂,含有涂层材料PVC表皮在-30 ℃低温爆破性能与涂层材料的Tg、低温拉伸性能、抗撕裂性能的关系并不大,而与涂层材料的阻尼性能直接相关。 材料的阻尼性能越好,其低温爆破性能越好。  相似文献   
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In this research, the experimental tests of quasi-static three-point bending and three-point bending fatigue were carried out for a ±25° biaxial braided carbon fibre reinforced polymer (CFRP) manufactured using vacuum assisted resin transfer moulding (VARTM). A finite element (FE) model was also set up for quasi-static testing and the prediction results revealed that local fibre volume fraction (FVF) is a primary source affecting the mechanical properties of braided CFRP. The fatigue of the braided CFRP was defined as three different stages according to the flexural modulus results. The damage modes of the test specimens were observed via a digital microscope and scanning electron microscope (SEM) and the process-induced defects were summarised. With compiled results and observations, this study provides a better understanding of failure and fatigue behaviour of biaxial braided composites and their flexural properties which offers a good basis for any further research in fibre volume fractions, structure design and manufacturing for braided CFRP.  相似文献   
9.
Valeriana jatamansi Jones (V. jatamansi) has been widely used for treating anxiety and its mechanism involves many aspects including GABA level. This study aimed to evaluate the anxiolytic potency of an iridoid fraction extracted from the radix and rhizomes of V. jatamansi. The iridoid fraction was extracted by using D101 resin; its major components were analysed preliminarily by thin layer chromatography, ultraviolet spectrophotometry and high-performance liquid chromatography; and its anxiolytic effects at 6 mg/kg (low-dose), 9 mg/kg (medium-dose) and 12 mg/kg (high-dose) were evaluated using the elevated plus maze test, the light–dark box test, the Vogel’s drinking conflict test, and the open field drink test. Its action mechanism was investigated using the ELISA. This study provided evidence on the anxiolytic potency of the iridoid fraction from V. jatamansi and revealed its action mechanism of regulating the GABA level.  相似文献   
10.
This paper reports a systematic study on the formation of particulate matter with diameter of <10 µm (i.e., PM10) during the combustion of two formulated water-soluble fractions (FWSFs) of bio-oil in a drop-tube-furnace (DTF) at 1400 °C under air or oxyfuel (30%O2/70%CO2) conditions. FWSF-1 was an organic-free calcium chloride solution with a calcium concentration similar to that in the bio-oil. FWSF-2 was formulated from the compositions of major organics in bio-oil WSF, doped with calcium chloride at the same concentration. The results suggest that similar to bio-oil combustion, the FWSF combustion produces mainly particulate matter with diameter of between 0.1 and 10 µm (i.e., PM0.1–10). Since there are no combustibles in the organic-free FWSF-1, the PM is produced via droplet evaporation followed by crystallization, fusion and further reactions to form CaO (in air or argon) or partially CaCO3 (under oxyfuel condition). With the addition of organics, FWSF-2 combustion produces PM10 shifting to smaller sizes due to extensive break up of droplets via microexplosion. Sprays with larger droplet size produce PM10 with increased sizes. The results show that upon cooling CaO produced during combustion in air can react with HCl gas to form CaCl2 in PM0.1. The predicted PSDs of PM10 based on the assumption that one droplet produces one PM particle is considerably larger than experimentally-measured PSDs of PM10 during the combustion of FWSFs, confirming that breakup of spray droplets takes place and such breakup is extensive for FWSF-2 when organics are present in the fuel.  相似文献   
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