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1.
Haiwei Cao Lei Yin Haihuan Cao Haiyang Guo Wenbo Ren Yanyan Li Jing Huang 《Journal of separation science》2022,45(10):1683-1692
Meropenem, a representative β-lactam antibiotic, is widely used to treat complicated and serious infections. Therefore, it is of great significance to monitor the plasma drug concentration for individualized antimicrobial therapy. This study first describes the development and validation of high-performance liquid chromatography–tandem mass spectrometry cubed method for monitoring meropenem in human plasma. Protein precipitation with methanol and a chromatographic analysis time of 7 min make this method simple and of high throughput. Meropenem was extracted from human plasma with recoveries >94.1%. Calibration curves were linear (R2 > 0.995) in the concentration range of 0.5–50 μg/mL. Overall accuracy and precision did not exceed 8.0% as well as no significant matrix effect was observed. The novelty of this method is that the triple-stage mass spectrometry technology improves the selectivity and sensitivity. A comparison of the presented method and traditional liquid chromatography–tandem mass spectrometry method was assessed in 44 patients treated with meropenem and Passing–Bablok regression coefficients and Bland–Altman plots showed that no significant difference between the two methods. So the triple-stage mass spectrometry method developed in this study is appropriate and practical for the monitor of meropenem in the daily clinical laboratory practice. 相似文献
2.
铒掺杂硼酸盐玻璃广泛应用于发光材料中,研究其发光动力学性质对于优化和提高其发光效率具有重要意义. 本文采用传统的熔融淬火法合成了摩尔比为2%的掺铒硼酸盐玻璃,并在低于硼酸盐玻璃转变温度(260 °C)下退火,退火处理后的掺铒硼酸盐玻璃光学性质得到了一定程度的提高. 硼酸盐玻璃未掺杂和掺杂Er3+的热性能采用差示扫描量热法以10 °C/min的速度进行测量. 同时还测量了掺铒硼酸盐玻璃发光机理的吸收光谱、激发光谱、稳态发射光谱、瞬态发射光谱和衰减动力学曲线. 实验结果表明Er3+在不同激发波长下556 nm处发射时具有不同的寿命,在掺铒硼酸盐玻璃中可能存在激发态阱,利用实验数据得到了激发态阱的深度为0.14 eV. 相似文献
3.
Yin Qingqing Xu Fen Sun Lixian Li Yaying Liao Lumin Wang Tao Guan Yanxun Xia Yongpeng Zhang Chenchen Wei Sheng Zhang Huanzhi Li Bin 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6583-6592
Journal of Thermal Analysis and Calorimetry - Polyethylene glycol (PEG) is widely used as phase change materials (PCMs). However, the leakage and low thermal conductivity issues restrict its... 相似文献
4.
The photoactivity of CdS nanorods was greatly improved by amino functionalized accordion-like MXene and spherical ZnSnO3. MXene possesses good electron transfer capability and ZnSnO3 presents matched energy band with CdS, which deeply accelerate the electron transfer and prevent the recombination of photogenerated electron-hole pair, leading to a strong photoelectrochemical (PEC) response. Taking the merit of the improved photoactivity of CdS nanorods, a novel PEC biosensor was constructed for DNA hydromethylation detection based on immune recognition of target molecule, where 5-hydroxymethyl-2′-deoxycytidine triphosphate (5hmdCTP) was employed as detect target, CdS/MXene was used as photoactive material, and ZnSnO3 was adopted as signal amplification unit. Under enzymatic covalent reaction of –CH2OH of 5hmdCTP with –NH2 of MXene, 5hmdCTP was specifically recognized and captured. Then, taking advantages of the covalent reaction between phosphate group of 5hmdCTP and ZnSnO3, the signal amplification unit was captured. Under the optimum conditions, this PEC biosensor presents wide linear range of 0.008–100 nM and low detection limit of 4.21 pM (3σ). The applicability of the developed method was evaluated by investigating the effect of Cd2+ and perfluorohexane compound pollutant on 5-hydroxymethylcytosine content in the genomic DNA of the roots and leaves of wheat seedlings. 相似文献
5.
Czechoslovak Mathematical Journal - A nonincreasing sequence π = (d1,…, dn) of nonnegative integers is a graphic sequence if it is realizable by a simple graph G on n vertices. In this... 相似文献
6.
惯性约束核聚变研究最近取得可喜成果,美国国家点火装置NIF装置实验上聚变增益达到了输入激光能量的三分之二.但是,这一成果与人们的预期还有较大差距,需要更深入研究激光与等离子体相互作用初期的动力学过程.我们发展了一种新方法,用单发长脉冲电子束团为探针,测量激光等离子体内电磁场在整个等离子体持续时间内的演化过程.实验中,高压静电电子源产生能量0—100 keV连续可调、脉宽10ns的电子束团.1 J,532 nm,脉宽约4 ns的激光脉冲聚焦到银靶上,激发产生等离子体.电子束团穿过激光等离子体,被其中的电磁场调制后成像,单发电子束团时间宽度会覆盖整个等离子体持续时间,通过分析电子束团的调制强度,推得等离子体内电磁场的变化.实验上成功实现了单发电子束团对整个激光等离子体内电场的诊断测量,获得了演化曲线,推算出实验条件下电子束通过路径上平均电场的最大值约为7.74×10~5 V/m. 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.
随着量子信息科学的迅速发展,以光子为物理载体的量子纠缠源已成为量子非定域性检验、量子通信、量子计算以及量子精密测量等领域必不可少的资源和重要技术手段。利用非线性介质中的自发参量下转换过程,从早期的β相偏硼酸钡晶体到后来的基于准相位匹配的周期性极化晶体等,双光子极化纠缠源凭借其在亮度和品质方面的优势得到了快速发展,这为基于卫星平台的广域量子通信和量子物理的基础检验提供了可能。从基本原理出发,系统介绍了近年来面向空间平台应用的量子纠缠源的发展和最新成果,特别是以“墨子号”量子科学实验卫星为代表的星载量子纠缠源载荷;此外,对国际上近几年关于星载量子纠缠源的进展以及未来发展趋势也进行了较为全面的介绍和分析。 相似文献
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