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1.
Li  Yi  Chu  Xing-chun  Wang  Xiang  Han  Zhong-xiang  Tang  Han-ling 《Optical Review》2022,29(6):469-475
Optical Review - Based on the scintillation index of Airy beam and exponentiated Weibull channel model, analytical expressions of outage probability for free-space optical (FSO) communication links...  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.
Li  Baixue  Li  Zhen  You  Kai  Qin  Anjun  Tang  Ben Zhong 《中国科学:化学(英文版)》2022,65(4):771-777
Science China Chemistry - Secrecy has received tremendous attention in modern information society. Innovative polymer-based fluorescent materials with multiple mode emission are quite desirable to...  相似文献   
4.
本文首先通过量子分子动力学方法结合多尺度冲击技术研究固相TNT晶体在冲击波加载下的初始分解反应路径及其产物组分变化.通过综合分析键长变化、电子布居和中间产物的存在寿命三个要素给出了不同冲击波速(3-15 km/s)下2类可能的初始分解路径:在低速冲击下(≤7 km/s),TNT发生部分分解和聚合,分解主要源于C-NO2键的断裂,初始分解产物以NO2为主;在高速冲击下(≥9 km/s)则发生完全分解,分解主要始于六元环的形成,即NO2基团上的O与相邻CH3基团上的H相结合,然后六元环被打破,生成了OH自由基,初始分解产物以CN、CO、C2和OH为主.另外,根据模拟数据我们从理论上给出了TNT(ρ0=1.7 g/cm~3)冲击Hugoniot关系为Us=3.377+1.363 u.随后以分子光谱理论为基础,采用含时密度泛函理论获取这些主要分解产物的紫外可见吸收谱、荧光发射谱及振动分辨的荧光发射谱.此项研究有助于我们深入认识TNT高温高压状...  相似文献   
5.
Catalysis Surveys from Asia - Co3O4 catalyst derived from Co-MOFs demonstrated rich active sites in the catalytic reaction. In this paper, we prepared the rod-like Co3O4 catalysts by calcining...  相似文献   
6.
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   
7.
Atopic dermatitis is characterized by leukocyte migration into the skin dermis and typically driven by excessive chemokine production at the site of inflammation. Conventional topical formulations such as gels, creams, and ointments are insufficient for this treatment because of low penetration of drug molecules into the targeted skin tissues. Herein, using a simple, green, sustainable strategy, we have developed novel primary zein nanoparticles embedded in curcumin (Cur) and coated with silk sericin (ZHSCs) for the topical delivery of Cur to penetrate into the dermis and exercise anti-dermatitis effects on the lesion with minimal side-effects. Transdermal delivery experiments and porcine skin fluorescence imaging indicated that ZHSCs facilitate the penetration of Cur across the epidermis layer of skin to reach deep-seated sites. Notably, ZHSCs = 1:0.25 (zein-to-silk sericin mass ratios of 1:0.25) markedly elevated the skin permeability and cumulative turnover of Cur transferred, which were provided a greater than a 3.8-fold increase relative to free Cur. The special nanoparticles of ZHS = 1:0.25 possessed the deepest localization depth and experience a transition of the particle structure and core-shell separation after penetrating into the dermis of skin. In a cell model of dermatitis induced by tumor necrosis factor α/interferon γ co-stimulation, compared with free Cur, Cur-loaded ZHS nanoparticles down-regulated the generation of inflammatory cytokines and chemokines in keratinocytes through suppression of the nuclear translocation of NF-κBp65 and hence exerted an anti-dermatitis effect. This strategy may provide new avenues and direction for the demanding issues of valid topical delivery systems.  相似文献   
8.
Tang  Yixuan  Tian  Qiang  Hu  Haiyan 《Nonlinear dynamics》2022,109(4):2319-2354
Nonlinear Dynamics - To describe the particular mechanical behaviors of beams with both uniform and non-uniform cross sections, such as the bidirectional bending, torsion-bending coupling, the...  相似文献   
9.
A series of FR-RPUF composites were prepared by a one-step water foaming process with ammonium polyphosphate (APP) and steel slag (SS) as flame retardants. Thermogravimetric analysis (TG), limiting oxygen index (LOI), UL-94 vertical combustion test, microscale combustion calorimetry (MCC), TG-Fourier transform infrared spectrometry (TG-FTIR), scanning electron microscopy (SEM), Raman spectra and FTIR were used to investigate the thermal stability, flame retardancy, combustion performance, gas phase products, and char residue morphology of FR-RPUF composites. TG test results showed that the initial decomposition temperature (T-5wt%) and char residue rate at 700°C of RPUF/APP/SS composites were significantly enhanced by the addition of APP and SS, and the thermal stability of the composites was improved. Flame retardant test results confirmed the significantly increased LOI values of RPUF/APP/SS composites with V-0 rating. TG-FTIR also confirmed the obviously decreased release of toxic gases and flammable gases in the combustion of RPUF/APP/SS composites. SEM and Raman spectra of char residues for the composites suggested that APP/SS system improved the compactness and graphitization degree of char layer for RPUF/APP/SS composite. The above researches provide a new strategy for the utilization of SS in fire safety engineering.  相似文献   
10.
We reveal the electronic structure in Yb Cd2Sb2,a thermoelectric material,by angle-resolved photoemission spectroscopy(ARPES)and time-resolved ARPES(tr ARPES).Specifically,three bulk bands at the vicinity of the Fermi level are evidenced near the Brillouin zone center,consistent with the density functional theory(DFT)calculation.It is interesting that the spin-unpolarized bulk bands respond unexpectedly to right-and left-handed circularly polarized probe.In addition,a hole band of surface states,which is not sensitive to the polarization of the probe beam and is not expected from the DFT calculation,is identified.We find that the non-equilibrium quasiparticle recovery rate is much smaller in the surface states than that of the bulk states.Our results demonstrate that the surface states can be distinguished from the bulk ones from a view of time scale in the nonequilibrium physics.  相似文献   
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