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151.
Chengfei Wang Xiaowei Li Ziquan Lv Yingyu Wang Yuebin Ke Xi Xia 《Journal of separation science》2020,43(12):2321-2329
A rapid and reliable method for the detection of five carbapenems (biapenem, imipenem, doripenem, meropenem, and faropenem) in water was developed and validated. After acidification of water samples with acetic acid, carbapenems were isolated using a Bond Elut PPL cartridge. The target compounds were separated using ultra high performance liquid chromatography with a chromatographic run time of 5 min and detected on a triple quadrupole mass spectrometer operated in positive electrospray ionization and multiple reaction monitoring mode. Mean recoveries were in the range of 76.6–106.5%, with satisfactory intraday and interday relative standard deviations lower than 10.0 and 10.8%, respectively. The limits of detection and quantification were in the ranges of 0.05–0.2 µg/L and 0.1–0.5 µg/L, respectively, depending on the analyte. The proposed method was applied to the analysis of river samples and wastewater samples from swine farms, and no carbapenems were detected in the collected samples. 相似文献
152.
Mingguang Wu Jiaqin Liao Lingxiao Yu Ruitao Lv Peng Li Wenping Sun Rou Tan Xiaochuan Duan Lei Zhang Fang Li Jiyoung Kim Kang Ho Shin Ho Seok Park Wenchao Zhang Zaiping Guo Haitao Wang Yongbing Tang George Gorgolis Costas Galiotis Jianmin Ma 《化学:亚洲杂志》2020,15(7):995-1013
Carbon is a simple, stable and popular element with many allotropes. The carbon family members include carbon dots, carbon nanotubes, carbon fibers, graphene, graphite, graphdiyne and hard carbon, etc. They can be divided into different dimensions, and their structures can be open and porous. Moreover, it is very interesting to dope them with other elements (metal or non‐metal) or hybridize them with other materials to form composites. The elemental and structural characteristics offer us to explore their applications in energy, environment, bioscience, medicine, electronics and others. Among them, energy storage and conversion are extremely attractive, as advances in this area may improve our life quality and environment. Some energy devices will be included herein, such as lithium‐ion batteries, lithium sulfur batteries, sodium‐ion batteries, potassium‐ion batteries, dual ion batteries, electrochemical capacitors, and others. Additionally, carbon‐based electrocatalysts are also studied in hydrogen evolution reaction and carbon dioxide reduction reaction. However, there are still many challenges in the design and preparation of electrode and electrocatalytic materials. The research related to carbon materials for energy storage and conversion is extremely active, and this has motivated us to contribute with a roadmap on ‘Carbon Materials in Energy Storage and Conversion’. 相似文献
153.
Nonlinear Dynamics - In this paper, we present a novel methodology for nonlinear dynamic analysis of chemical processes that are posed as differential–algebraic equations (DAE) systems. With... 相似文献
154.
Nonlinear Dynamics - This paper discusses the finite time consensus (FTC) issue of nonlinear heterogeneous multi-agent systems (HMASs) by combining integral sliding-mode control (SMC),... 相似文献
155.
Polymer-bonded sugars (PBSs) can be used as a substitute material for polymerbonded explosives (PBXs) due to their ability to simulate the mechanical properties... 相似文献
156.
Yanxia Xu Yanbing Lv Ruili Wu Huaibin Shen Huawei Yang Han Zhang Jinjie Li Lin Song Li 《Particle & Particle Systems Characterization》2020,37(3):1900441
Indium phosphide (InP) quantum dots (QDs) are ideal substitutes for widely used cadmium-based QDs and have great application prospects in biological fields due to their environmentally benign properties and human safety. However, the synthesis of InP core/shell QDs with biocompatibility, high quantum yield (QY), uniform particle size, and high stability is still a challenging subject. Herein, high quality (QY up to 72%) thick shell InP/GaP/ZnS core/shell QDs (12.8 ± 1.4 nm) are synthesized using multiple injections of shell precursor and extension of shell growth time, with GaP serving as the intermediate layer and 1-octanethiol acting as the new S source. The thick shell InP/GaP/ZnS core/shell QDs still keep high QY and photostability after transfer into water. InP/GaP/ZnS core/shell QDs as fluorescence labels to establish QD-based fluorescence-linked immunosorbent assay (QD-FLISA) for quantitative detection of C-reactive protein (CRP), and a calibration curve is established between fluorescence intensity and CRP concentrations (range: 1–800 ng mL−1, correlation coefficient: R2 = 0.9992). The limit of detection is 2.9 ng mL−1, which increases twofold compared to previously reported cadmium-free QD-based immunoassays. Thus, InP/GaP/ZnS core/shell QDs as a great promise fluorescence labeling material, provide a new route for cadmium-free sensitive and specific immunoassays in biomedical fields. 相似文献
157.
Meccanica - A flow mixing nozzle can produce satisfactory atomization for heavy oil. However, the study of the internal flow pattern of this nozzle, along with the spray morphology and its... 相似文献
158.
Hongfa Lv Lianping Wang Shuang Liu Wei Hu Jianfeng Wang Xuming Deng Jinying Gao 《Molecules (Basel, Switzerland)》2022,27(7)
Listeria monocytogenes (L. monocytogenes) is an important Gram-positive food-borne pathogen that severely threatens public health. A checkerboard microdilution method was performed to evaluate the synergistic effect of lithocholic acid (LCA) with Gentamicin (Genta) against L. monocytogenes. BacLight LIVE/DEAD staining, scanning electron microscopy and biofilm inhibition assays were further used to explore the bactericidal effect and antibiofilm effect of this combination on L. monocytogenes. Additionally, the synergistic effects of LCA derivatives with Genta were also evaluated against L. monocytogenes, S. aureus and S. suis. The results indicated that a synergistic bactericidal effect was observed for the combined therapy of LCA at the concentration without affecting bacteria viability, with Genta. Additionally, LCA in combination with Genta had a synergistic effect against Gram-positive bacteria (L. monocytogenes, S. aureus and S. suis) but not against Gram-negative bacteria (E. coli, A. baumannii and Salmonella). BacLight LIVE/DEAD staining and scanning electron microscopy analysis revealed that the combination of LCA with Genta caused L. monocytogenes membrane injury, leading to bacteria death. We found that 8 μg/mL LCA treatment effectively improved the ability of Genta to eradicate L. monocytogenes biofilms. In addition, we found that chenodeoxycholic acid, as a cholic acid derivative, also improved the bactericidal effect of Genta against Gram-positive bacteria. Our results indicate that LCA represents a broad-spectrum adjuvant with Genta for infection caused by L. monocytogenes and other Gram-positive pathogens. 相似文献
159.
Xinchun He Wenwen Lv Xiaomeng Shi Hao Wei Min Shi Feijun Wang 《Tetrahedron letters》2018,59(11):1038-1041
Phosphonylation of the pretreated 2-(hydroxymethyl)phenol derivatives with acetic anhydride using trialkylphosphites as the nucleophilic reagents was reported, providing a practical way to the synthesis of novel highly steric 3,3′-bis-substituted benzo[d][1,2]oxaphosphole 2-oxides. 相似文献
160.
随着社会经济的高速发展,能源的短缺和生态的破坏引起了人们的关注。近年来,寻找合适的解决方案已成为关注的重点。作为一种绿色环保技术,光催化由于其高效、低成本等优点而成为能源和环境问题的研究热点。在许多光催化材料中,三元硫化物硫化铟锌(ZnIn2S4)由于具有可见光响应特性、简单的制备方法和出色的稳定性而表现出巨大的潜力。然而,较高的载流子复合率限制了其光催化性能。近年来,许多研究报道了改性ZnIn2S4以提高其光催化性能,在此,本文详细介绍了各种改性研究,包括ZnIn2S4单体的合成、半导体化合物的结构、贵金属沉积、碳元素改性、离子掺杂。然后,系统完整地总结了ZnIn2S4在光催化、降解有机污染物、去除六价铬、还原CO2和有机合成等方面表现出的光催化特性和机理。最后,对ZnIn2S4的发展前景提出了展望,以期ZnIn2S4光催化剂得到更广泛和深入的研究,尽快在实际生产中得到应用。 相似文献