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101.
近年来,有机场效应晶体管(OFETs)由于在柔性器件和可穿戴电子学中的潜在应用受到了学术界和工业界的普遍关注,尤其是以聚合物半导体材料构筑的晶体管性能得到了快速的发展.如何设计合成用于OFETs的高性能聚合物半导体材料,一直是我们的追求目标.然而,分子结构对迁移率的影响仍缺少系统的比较.本文综述了近年来国内外新型聚合物材料的最新进展.我们按照材料的种类以及载流子的传输类型进行了分类,对高性能聚合物材料的发展过程、材料的设计思路以及相应的FETs性能进行了系统地归纳总结.通过研究分子及分子聚集态结构与器件性能之间的关系,希望为以后设计合成新型的高性能的聚合物材料提供有益的借鉴和指导. 相似文献
102.
对QuEChERS前处理方法从提取、分离、净化等方面进行优化以减弱样本中的基质效应,提高灵敏度;使用提取试剂(含0.1%甲酸的乙腈:甲醇=70:30,V/V)进行提取,加入无水硫酸镁、硼酸钠、研磨珠进行提取分离,使用混合净化剂(十八烷基硅烷(C18):乙二胺-N-丙基硅烷(PSA)=1:2,m/m)进行净化,UPLC-MS/MS测定,外标法定量。结果表明:在优化条件下,苯丙胺类及其相关9种物质的色谱峰分离良好,且各标准化合物的线性相关系数均大于0.991,检出限(LODs)为0.3~1.0 ng/mL,定量限(LOQs)均为2.5 ng/mL;血液添加标准品样本在低(20 ng/mL)、中(100 ng/mL)、高(400 ng/mL)3个浓度的加标回收率为80.1%~103.1%,精密度相对标准偏差(RSD)为1.5%~8.6%;临床4份检测样本中有3份检出苯丙胺类阳性,准确率为71.5%~99.1%。所建立的QuEChERS方法与UPLC-MS/MS结合的分析方法可应用于血液样本中苯丙胺类及其相关9种药物的同时检测分析。 相似文献
103.
The isoscaling behavior in the reaction system of 58,64Ni + 9Be has been studied by using the heavy-ion phase-space exploration(HIPSE) model. The extracted isoscaling parameters α and β for both heavy and light fragments for HIPSE model calculations are in good agreement with recent experimental data. The investigation shows that the parameters in the HIPSE model have some effect on the isoscaling parameter. The isoscaling parameters for hot and cold fragments have been extracted. 相似文献
104.
Assuming a core plus valence nucleon structure, one-nucleon removal reaction is investigated within the framework of few-body Glauber theory. Fermi-type distribution is used for the core density, while the wavefunction of the valence nucleon is calculated by solving the single particle eigenvalue problem of the SchrSdinger equation with the Woods-Saxon potential. The parallel momentum distribution (P//) of the fragments is calculated for isotopes with 3 〈 Z 〈 18. A remarkable scaling property is observed from the dependence of the dimensionless quantity P^2 v/R^2 e on the full width at half maximum of the parallel momentum distribution (FWHMp//). R^2 v/R^2 c is a measure of the exotic extent of the nuclear halo. Based on the obtained 2 2 scaling law, FWHMp// can be used as an experimental observable to extract R^2 v/R^2 c and measure the exotic extent for the nuclear halo. 相似文献
105.
The local temperature effect on strangeness enhancement in relativistic heavy ion collisions is discussed in the framework of the thermal model in which the K^+ /h^+ ratio becomes smaller with increasing freeze-out temperature. Considering that most strangeness particles of final-state particles are from the kaon meson, the temperature effect may play a role in strangeness production in hot dense matter where a slightly different temperature distribution in different areas could be produced by jet energy loss. This phenomenon is predicted by thermal model calculation at RHIC energy. The /Ф ratio in central Au+Au collisions at 200GeV from the thermal model depends on the freeze-out temperature obviously when γs is different. It should be one of the reasons why strangeness enhancements of and Ф are different though they include two strange quarks. These results indicate that thermodynamics is an important factor for strangeness production and the strangeness enhancement phenomenon. 相似文献
106.
Isoscaling Behavior in ^48,40Ca+^9Be Collisions at Intermediate Energy Investigated by the HIPSE Model 下载免费PDF全文
The fragment production cross sections for 140 Me V/nucleon ^48,40 Ca^+9 Be reactions are calculated by the heavyion phase space exploration (HIPSE) model. Isoscaling behavior is observed. The isoscaling parameters a and β for both heavy and light fragments from the HIPSE model calculations are in good agreement with the experimental data. It is shown that the potential parameters in the HIPSE model have very little effect on the isoscaling parameters. The effect of the excitation energy and evaporation on the isoscaling behavior is also discussed. 相似文献
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109.
SrTiO3双晶基片是高温超导电子学研究中外延YBCO薄膜所需要的基础材料;是制作高温超导量子干涉器件(SQUID)的核心。由于其特殊的制造工艺,加之研究因素所附加的高昂成本,至今只有少数国家涉足这一领域。文中展示作者在钛酸锶双晶研究方面所取得的阶段性进展。 相似文献
110.
The present detection limit for 182Hf at CIAE HI-13 AMS systems could not satisfy various applications (e. g. detection of a nearby supernovae signal). Therefore, techniques were developed in this work to improve the AMS measurement of 182Hf mainly on building a new injector and using a method that based on solid-phase reaction for the preparation of HfF4 samples from HfO2. The experimental results show that mass resolution of the injector can reached 630, and the F-/O- and beam current of 180HfF5- for HfF4 samples produced by dry method is about 2—3 times and 1.5 times of that by previously method, respectively. 相似文献