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1.
水泥熟料分析是一个经典的综合性实验,涉及重量分析和配位滴定分析的很多原理及操作。为了有效开展实验教学、缩短课堂讲解时间、客观评价学生实验数据及结果,我们开展了线上线下混合式教学,引导学生课前自主学习,训练学生综合和创新实验技能。这一改革提高了实验教学质量,取得了较好的教学效果。  相似文献   
2.
Herein, we investigated the analytical features of potentiometric immunosensors for detection of alpha-fetoprotein (AFP) in hepatocellular carcinoma at different electrodes, such as carbon fiber microelectrode (CFME) and carbon-disk electrode (CDE), respectively. To construct such an immunosensor, anti-AFP capture antibodies were first conjugated covalently onto the activated electrodes through typical carbodiimide coupling. Thereafter, one-step immunoreaction protocol was successfully introduced to develop a new potentiometric immunoassay upon addition of AFP. Accompanying the antigen-antibody reaction, the surface charges of the modified electrodes were changed for the readout of electric potential. Results indicated that the linear range of CDE-based immunosensor was 0.1–100 ng mL−1 AFP, whereas the assay sensitivity by using CFME could be further increased to 3.2 pg mL−1 with the linear range from 0.01 to 500 ng mL−1 AFP. Meanwhile, CFME-based immunosensor showed high sensitivity, good reproducibility and specificity, and could be utilized for the analysis of human serum specimens with consistent results relative to commercialized ELISA kit.  相似文献   
3.
Acta Mathematica Sinica, English Series - We are interested in the existence and asymptotic behavior for the least energy solutions of the following fractional eigenvalue problem $$\left({\rm{P}}...  相似文献   
4.
As one of the most attractive non-radiative power transfer mechanisms without cables,efficient magnetic resonance wireless power transfer(WPT)in the near field has been extensively developed in recent years,and promoted a variety of practical applications,such as mobile phones,medical implant devices and electric vehicles.However,the physical mechanism behind some key limitations of the resonance WPT,such as frequency splitting and size-dependent efficiency,is not very clear under the widely used circuit model.Here,we review the recently developed efficient and stable resonance WPT based on non-Hermitian physics,which starts from a completely different avenue(utilizing loss and gain)to introduce novel functionalities to the resonance WPT.From the perspective of non-Hermitian photonics,the coherent and incoherent effects compete and coexist in the WPT system,and the weak stable of energy transfer mainly comes from the broken phase associated with the phase transition of parity-time symmetry.Based on this basic physical framework,some optimization schemes are proposed,including using nonlinear effect,using bound states in the continuum,or resorting to the system with high-order parity-time symmetry.Moreover,the combination of non-Hermitian physics and topological photonics in multi-coil system also provides a versatile platform for long-range robust WPT with topological protection.Therefore,the non-Hermitian physics can not only exactly predict the main results of current WPT systems,but also provide new ways to solve the difficulties of previous designs.  相似文献   
5.
In the present study, a specific and sensitive approach using ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry was developed and validated for the quantitative analysis of 14 constituents in rat plasma, liver, and heart. The method was fully validated and successfully applied to pharmacokinetic, hepatic disposition, and heart tissue distribution studies of 14 compounds after the oral administration of Qi-Li-Qiang-Xin capsule. Ginsenoside Rb1, alisol A, astragaloside IV, and periplocymarin were found to be highly exposed in rat plasma, while toxic components such as hypaconitine, mesaconitine, and periplocin had low circulation levels in vivo. Moreover, sinapine thiocyanate, neoline, formononetin, calycosin, and alisol A exhibited significant liver first-pass effects. Notably, high levels of alisol A, periplocymarin, benzoylmesaconine, and benzoylhypaconine were observed in the heart. Based on high exposure and appropriate pharmacokinetic features in the systemic plasma and heart, astragaloside IV, ginsenoside Rb1, periplocymarin, benzoylmesaconine, benzoylhypaconine, and alisol A can be considered as the main potentially effective components. Ultimately, the results provide relevant information for discovery of effective substances, as well as further anti-heart failure action mechanism investigations of Qi-Li-Qiang-Xin capsule.  相似文献   
6.
曾彦  梁浩  管诗雪  王俊普  梁文嘉  黄梦阳  彭放 《中国物理 B》2022,31(1):16104-016104
Structural stability in terms of the decomposition temperature in LiMn2O4 was systematically investigated by a series of high-temperature and high-pressure experiments.LiMn2O4 was found to have structural stability up to 5 GPa at room temperature.Under ambient pressure,the compound decomposed at 1300℃.The decomposition temperature decreased with increasing pressure,yielding more complex decomposed products.Below the decomposition temperature,the crystal structure of LiMn2O4 varied with pressure.The presented results in this study offer new insights into the thermal and pressure stability of LiMn2O4 materials as a cathode for lithium-ion batteries that can operate under extreme conditions.Therefore,these findings may serve as a useful guide for future work for improving lithium-ion batteries.  相似文献   
7.
Development of subcellular organelle-targeted bioimaging probes is of great importance in the field of early detection of diseases and exploring the behaviors of subcellular organelles. Herein, we present a triphenylphosphonium functionalized conjugated macrocyclic tetramaleimide (TPP-CMT) as a mitochondrial-targeting bioimaging probe. The core of TPP-CMT is obtained by connecting two pyrenes and two benzenes through four maleimides. This unique structure endows TPP-CMT with exceptional far red/near-infrared aggregation-induced emission (FR/NIR-AIE) characteristics. TPP-CMT is an excellent fluorescent emitter in most solvents and even in solid states. The quantum yield of TPP-CMT was higher than 27% when dissolved in common middle-polarity organic solvent and this value remained at 28.2% in its solid state. The introduction of four triphenylphosphonium on maleimide positions endows TPP-CMT with mitochondrial-targeting ability. Thanks to the FR/NIR-AIE characteristics and the mitochondrial-targeting ability, this well-designed fluorescent probe was successfully employed for mitochondrial targeting bioimaging of HeLa and HepG2 cells.   相似文献   
8.
本文分析了新冠疫情形势下《聚合物改性》课程线上教学实施的问题。依托"QQ课堂"和"超星学习通"平台,通过"在线讲授理论环节"和"居家实验"相结合的形式,开展了融"理论+实践"为一体的《聚合物改性》课程在线教学。把需要在实验室完成的实验生活化,既锻炼了学生的动手能力又能尝试自己制作的美食,既激发了学生的学习兴趣,又进行了劳动教育。这些探索和实践有望为疫情期间其它化学类课程的在线教学提供一定的借鉴和参考。  相似文献   
9.
Czechoslovak Mathematical Journal - We propose a lower bound sequence for the minimum eigenvalue of Hadamard product of an M-matrix and its inverse, in terms of an S-type eigenvalues inclusion set...  相似文献   
10.
基于 HL-2M 托卡马克初始等离子体放电的工程需求,设计并研制了直流辉光放电清洗系统,包括电 极、馈线、电源、控制以及监测等关键部件和辅助子系统。研制完成后开展了系统装配和工程调试,并投入到首 次等离子体放电。实验结果表明,该直流辉光放电系统运行稳定、可靠,且此辉光放电清洗显著降低了真空室本 底杂质浓度,能满足 HL-2M 装置初始等离子体放电的壁条件需求。  相似文献   
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