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The present study firstly aimed at developing a multi-residue method to identify and quantify 38 veterinary antibiotics (belonging to five different classes) not only for raw swine wastewater but also for wastewater differently treated by different units. The proposed method is based on a solid-phase extraction procedure and ultra high performance liquid chromatography with mass spectrometry. For sample preparation, the optimal loading sample volume was selected as 50 mL, the pH of which was adjusted to approximately 3.0 using formic acid. Then 0.1 g/L ethylenediaminetetraacetic acid disodium salt was added. The recovery rates for different types of wastewaters were in the range of 35.94–124.51% and the relative standard deviations were in the range of 0.36–14.62%. All the matrix standard curves exhibited high linearity (0.9956–0.9999). The matrix effects for the target antibiotics ranged from –61.73 to +148.75%. To ensure the practicality of the method, we performed the detection of the actually added concentration to determine method detection limits and quantitation limits. The quantitation limits of most of the target antibiotics were 0.04 μg/L, except for spiramycin (0.1 μg/L) and roxithromycin (0.2 μg/L). This optimized and validated method was applied to analyze antibiotic residues in swine water samples from four swine farms.  相似文献   
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Acta Mathematica Sinica, English Series - For a finite group G, the power graph $$\cal{P}(G)$$ is a simple connected graph whose vertex set is the set of elements of G and two distinct vertices x...  相似文献   
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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   
5.
Hu  Duo-Duo  Gao  Qian  Dai  Jing-Cheng  Cui  Ru  Li  Yuan-Bo  Li  Yuan-Ming  Zhou  Xiao-Guo  Bian  Kang-Jie  Wu  Bing-Bing  Zhang  Kai-Fan  Wang  Xi-Sheng  Li  Yan 《中国科学:化学(英文版)》2022,65(4):753-761
Science China Chemistry - A light-induced, nickel-catalyzed three-component arylsulfonation of 1,3-enynes in the absence of photocatalyst is reported. This methodology exhibited mild conditions,...  相似文献   
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量子通信是当前量子信息领域的研究前沿和热点。增益开关半导体激光产生技术是一种实现脉冲激光产生的成熟方法,将其与注入锁定技术结合,可以满足量子通信应用对激光脉冲的需求。系统地介绍了增益开关半导体激光器的工作原理和注入锁定方案,以及其在量子密钥分发、量子随机数产生等方面的应用现状,着重从物理原理、实验方案和最新研究进展等方面进行阐述,并对其下一步的发展进行简要展望。  相似文献   
7.
邵云 《大学物理》2022,(1):32-38
文章逐个分析计算了单摆的摆角、摆球的自转、摆线质量、空气浮力以及空气阻力对于单摆周期的影响,以1 m长5°小幅单摆为例,得到这5种因素带来的系统相对误差分别为+0.45‰、+0.02‰、-0.45‰、+0.07‰、-0.14‰,合计仅为-0.05‰,即这5种误差因素几乎相互抵消,小幅单摆实验在理论上的系统误差极小.文章给出了较为详细的推理、计算和分析过程,尤其空气阻力矩的推理过程以及图、表等,意在提供较为完整和准确的认识.文末,针对人们在空气阻力认识上可能存在的某些不足,文章给出了几点必要的说明.  相似文献   
8.
Juglandis Mandshuricae Cortex is the bark of Juglans mandshurica Maxim., which has been used as a folk medicine plant in China and India. In this study, an ultra-high performance liquid chromatography–quadrupole/orbitrap high-resolution mass spectrometry method was developed to clarify and quantify the chemical profiling of Juglandis Mandshuricae Cortex rapidly. A total of 113 compounds were characterized. Among them, seven flavonoids were simultaneously quantified in 15 min, including myricetin, myricetrin, taxifolin, kaempferol, quercetin, quercitrin, and naringenin. The method was validated for accuracy, precision, and the limits of detection and quantification. All calibration curves showed a good linear relationship (r > 0.9990) within test ranges. The intra- and inter-day relative standard deviations were less than 2.16%. Accuracy validation showed that the recovery was between 95.6 and 101.3% with relative standard deviation values below 2.85%. The validated method was successfully applied to determine the contents of seven flavones in Juglandis Mandshuricae Cortex from seven sources and the contents of these places were calculated respectively. This method provides a theoretical basis for further developing the medicinal value of Juglandis Mandshuricae Cortex.  相似文献   
9.
Bulk assemblies of zero-dimensional (0D) metal halides with ‘host-guest’ system provide a promising platform for rationally structural tunability and photoluminescence modulation. In this work, we first report a series of ternary 0D metal halides, (bmpy)9[Pb3Cl11](MnCl4)2-2x(SbCl5)2x (bmpy+ = 1-buty-1-methylpyrrolidinium+, C9NH20+), where the organic cation bmpy+ cocrystallizes with [Pb3Cl11]5- trimer clusters, [MnCl4]2? tetrahedra, and [SbCl5]2? pyramids. The emission color of (bmpy)9[Pb3Cl11](MnCl4)2-2x(SbCl5)2x can be easily tuned from green to warm white and finally to orange-red by controlling the excitation wavelength or the [SbCl5]2?/[MnCl4]2? molar ratio, promising its potential for application in multicolor light-emitting devices or even in encrypting multilevel optical codes. This work presents a novel structural modulation strategy to fabricate superior ordered single-crystalline multicomponent materials with multifunctionalities of 0D luminescent metal halides.  相似文献   
10.
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   
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