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Development of a class-specific polyclonal antibody-based indirect competitive ELISA for detecting fluoroquinolone residues in milk

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第7期13卷 545-554页

作者： Guo-ying FAN Ruo-song YANG jin-qing jiang Xin-yao CHANG Jun-jie CHEN Yong-hua QI Shi-xiu WU Xue-feng YANG College of Veterinary Medicine Northwest A&F UniversityYangling 712100China College of Animal Science Henan Institute of Science and TechnologyXinxiang 453003China

Modified 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide(EDC)method was employed to synthesize the artificial antigen of norfloxacin(NOR),and New Zealand rabbits were used to produce anti-NOR polyclonal antibody(pAb).Based on the checkerboard titration,an indirect competitive enzyme-linked immunosorbent assay(icELISA) standard curve was *** assay was sensitive and had a working range from 0.12 to 68.40 ng/ml,with the half maximal inhibitory concentration(IC50)and limit of detection(LOD)values of 2.7 ng/ml and 0.06 ng/ml,*** produced pAb exhibited high cross-reactivity to fluoroquinolones(FQs)tested,and the IC50 values to enoxacin,ciprofloxacin,and pefloxacin were 3.1,3.4,and 4.1 ng/ml,*** also indicated that the concentrations of NaOH and methanol in assay buffer should not be higher than 10%and 30%.When spiked in milk at 5,20,and 50 ng/ml,the recoveries for NOR,enoxacin,ciprofloxacin,and pefloxacin ranged 90.5%-98.0%,84.0%-95.2%,94.0%-106.0%,and 89.5%-100.0%,*** results suggest that this class-specific pAb-based icELISA could be utilized for the primary screening of FQ residues in animal-original products.

关键词： Norfloxacin Fluoroquinolones Indirect competitive ELISA Class-specificity Milk

Analysis of 19-nortestosterone residue in animal tissues by ion-trap gas chromatography-tandem mass spectrometry

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第6期12卷 460-467页

作者： jin-qing jiang Lei ZHANG Guang-ling LI Hai-tang ZHANG Xue-feng YANG Jun-wei LIU Ren-feng LI Zi-liang WANG Jian-hua WANG College of Veterinary Medicine Northwest A &F University Yangling 712100 China College of Animal Science Henan Institute of Science and Technology Xinxiang 453003 China College of Resources and Environment Henan Institute of Science and Technology Xinxiang 453003 China

A rapid sample treatment procedure for the gas chromatography-tandem mass spectrometry （GC-MS） determination of 19-nortestosterone （19-NT） in animal tissues has been developed. In our optimized procedures, enzymatic hydrolysis with β-glucuronidase from Escherichia coliwas performed in an acetate buffer （pH 5.2, 0.2 mol/L） Next, the homogenate was mixed with methanol and heated at 60℃ for 15 min, then placed in an ice-bath at -18℃ for 2 h. After liquid-liquid extraction with n-hexane, the analytes were subjected to a normal-phase solid phase ex- traction （SPE） C18 cartridge for clean-up. The dded organic extracts were derivatized with heptafluorobutydc anhydride （HFBA）, and then the products were injected into GC-MS. Using electron impact mass spectrometry （El-MS） with positive chemical ionization （PCI）, four diagnostic ions （mlz 666, 453, 318, and 306） were determined. A standard calibration curve over the concentration range of 1-20 ng/g was reached, with Y=467084X-68354 （R^2=0.9997） for 19-NT, and the detection limit was 0.3 ng. When applied to spiked samples collected from bovine and ovine, the recoveries ranged from 63% to 101% with relative standard deviation （RSD） between 2.7% and 8.9%. The procedure is a highly efficient, sensitive, and more economical method which offers considerable potential to resolve cases of suspected nandrolone doping in husbandry animals.

关键词： 19-Nortestosterone (19-NT) Gas chromatography-tandem mass spectrometry (GC-MS) Animal tissues

Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang jiang Tian MAO jin-Song WANG Xiu-qing HU Xiao-Xin ZHANG Liping FU Nan JIA Tianfang WANG National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia Yu Wang Chun Cheng Yang qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

The gut-eye axis:from brain neurodegenerative diseases to age-related macular degeneration

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Neural Regeneration Research 2025年第10期20卷 2741-2757页

作者： Qianzi jin Suyu Wang Yujia Yao Qin jiang Keran Li Department of Ophthalmology The Affiliated Eye Hospital of Nanjing Medical UniversityNanjingJiangsu ProvinceChina The Fourth School of Clinical Medicine Nanjing Medical UniversityNanjingJiangsu ProvinceChina

Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts ***,the specific pathogenesis remains unclear,and effective early treatment options are consequently *** microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a *** intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other *** dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many *** recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the ***,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s ***,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular ***,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable *** such,the intestinal flora may play an important role in age-related macular *** the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic ***,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular ***-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the inte

关键词： age-related macular degeneration biological agents blinding eye disease dietary nutrition fecal microbial transplantation gut-eye axis intestinal flora metabolite microecology neurodegenerative disease

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-Lin jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： CO 2 methanation Metal hydride Ni catalysts Carbonate Metal-carbonate interface

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城市燃气发展规划的探讨

煤气与热力 2005年第8期25卷 67-68页

作者：金庆江唐山市燃气总公司河北唐山063000

分析了城市燃气现状中管网及紧缺的气源与燃气发展的矛盾,提出了燃气发展规划思路。

关键词：管网气源发展规划

水电站有载调压变压器重瓦斯动作原因分析和处理

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水电站机电技术 2023年第6期46卷 117-119页

作者：金清江天台县龙溪水库事务中心浙江天台317200

电力系统广泛使用的都是无载调压变压器,应用的较少,主要应用于电压可能发生较大变化的电网,具有专用的分接头切换开关,能根据二次电压的变化(依据负荷情况)以及事先设定的动作电压变化值和延时时间,自动调节分接开关位置,从而调整变压... 详细信息

电力系统广泛使用的都是无载调压变压器,应用的较少,主要应用于电压可能发生较大变化的电网,具有专用的分接头切换开关,能根据二次电压的变化(依据负荷情况)以及事先设定的动作电压变化值和延时时间,自动调节分接开关位置,从而调整变压器低压侧电压。按照变压器运行维护规程,对气体继电器保护动作的可能原因、日常巡查的内容,都作了相应的规定,但这些规定具有典型性,是相对比较常见的瓦斯保护动作案例。针对水电站110 kV有载调压变压器分接开关操作时发生的重瓦斯保护动作致主变跳闸事件,就有载调压分接开关操作引起重瓦斯保护动作的进行原因分析、故障处理、防范措施等非典型案例阐述,分析其原因,进行故障处理,具有非典型案例的性质。案例阐述可供广大发、变、输、供等电力运行、维护、检修人员参考和借鉴。

关键词：变压器有载调压瓦斯保护气体继电器水电站