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冻融作用与含水量对黑土中活性有机碳的影响

土壤通报 2024年第4期55卷 953-959页

作者：王楠王洋崔政武袁玉玉徐林浩张珂瑜中国科学院东北地理与农业生态研究所吉林长春130102 中国科学院大学北京100049 延边大学吉林延吉133002

【目的】明确冻融条件对土壤活性有机碳影响程度,为黑土区有机碳保持和碳平衡的研究提供基础数据和理论依据。【方法】以德惠地区典型中层黑土为研究对象,通过冻融控制试验,研究不同冻融频次、冻结时间、冻融温度及土壤含水量对土壤活... 详细信息

【目的】明确冻融条件对土壤活性有机碳影响程度,为黑土区有机碳保持和碳平衡的研究提供基础数据和理论依据。【方法】以德惠地区典型中层黑土为研究对象,通过冻融控制试验,研究不同冻融频次、冻结时间、冻融温度及土壤含水量对土壤活性有机碳的影响。【结果】土壤活性有机碳组分对冻融条件的响应差异显著。土壤可溶性有机碳、轻组有机碳、颗粒有机碳含量随着冻融频次的增加逐渐增加,当冻融20次后,含量变化幅度较小,逐渐趋于稳定;土壤微生物量碳含量在冻融12次后处于0.160~0.164 g kg^(-1)之间波动。冻结温度降低、融化温度升高均可促进土壤可溶性有机碳、轻组有机碳和颗粒有机碳含量增加,而土壤微生物量碳含量则随冻结温度的降低而降低,随融化温度的升高而增加,但含量仍比对照处理低10.42%~24.48%。土壤可溶性有机碳、轻组有机碳和颗粒有机碳含量随着冻结时间的增加差异显著,冻结时间为12~48 h时,增幅较大;冻结时间增加使得土壤微生物量碳含量显著降低,冻结时间为96 h时,降幅可达52.60%。随着土壤含水量增加可溶性有机碳、轻组有机碳和颗粒有机碳含量逐渐增加,当含水量为田间持水量的80%~100%时,轻组有机碳含量增加最显著,增幅达到9.69%~38.48%;而土壤微生物量碳含量则逐渐降低,当含水量为田间持水量的80%~100%时,含量降低不显著。【结论】冻融循环有利于增强或维持土壤有机碳含量,频繁的冻融作用能够提高部分活性有机碳组分含量,促进土壤养分循环。

关键词：冻融循环含水量黑土活性有机碳

Determination of Tetracyclines and Their Epimers in Agricultural Soil Fertilized with Swine Manure by Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry

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Journal of Integrative Agriculture 2012年第7期11卷 1189-1198页

作者： ZHENG Wen-li zhang Li-fang zhang ke-yu WANG Xiao-yang XUE Fei-qun key Laboratory of Veterinary Drug Safety Evaluation and Residues Research Shanghai Veterinary Research InstituteChinese Academy of Agricultural SciencesMinhang 200241P.R.China

A rapid, sensitive and specific ultra-high-performance liquid chromatography tandem mass spectrometry （UPLC-MS） method was developed for the analysis of tetracycline antibiotics, including tetracycline （TC）, oxytetracycline （OTC）, chlortetracycline （CTC） and their 4-epimers （4-epiTCs） in agricultural soil fertilized with swine manure. Soil samples were extracted and cleaned-up with 10 mL EDTA-McIlvaine buffer solution （pH 4.0）, then cleaned-up and pre-concentrated using the Oasis MAX cartridge and then eluted with 1 mL solution by mixing formic acid, methanol and water at a ratio of 2：15：83 （v/v/v）. The purified samples were separated by an ACQUITY UPLC BEH C18 column using acetonitrile and water containing 0.1% formic acid mobile phase and detected by a single quadrupole MS. The limits of detection for the soil extraction method （LODsoil） ranged from 0.6-2.5 lag kg-~ with recoveries from 23.3-159.2%. Finally, the method was applied to an agricultural field in an area with intensive pig-fattening farming. Tetracyclines were detected in soil from 2.8 to 42.4 μg kg-1 soil. These results demonstrate that soil from swine farms can become severely contaminated with tetracycline antibiotics and their metabolites.

关键词： tetracyclines epimers ultra performance liquid chromatography soil solid phase extraction

Spectrum-Effect Relationship Between High Performance Liquid Chromatography Fingerprints and Anticoccidial Activities of a Compound Chinese Medicine

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Journal of Integrative Agriculture 2014年第5期13卷 1082-1089页

作者： XIAO Sui FEI Chen-zhong zhang Li-fang ZHENG Wen-li zhang ke-yu XUE Fei-qun key Laboratory of Veterinary Drug Safety Evaluation and Residues Research Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences

Quality control and screening of active substances in traditional Chinese medicines have been performed using fingerprint analysis. The spectrum-effect relationship between chromatography fingerprints and efficacy of herbal drugs is considered as a potentially useful method for determining active ingredients in complex mixtures. The study was designed to develop a method for determining the bioactive components of a compound Chinese medicine called Tiefeng based on spectrum-effect relationships between high-performance liquid chromatography （HPLC） fingerprints and anticoccidial activities. Four peaks of the established HPLC fingerprint indicate the main bioactive components of this medicine. In addition, pharrnacodynamic atlas was defined and used to assess the anticoccidial activity of Tiefeng from different sources for the first time. We found that the level of anticoccidial activity of Tiefeng was consistent with the degree of similarity between the pharmacodynamic atlas and chromatogram of any sample. Furthermore, effect of this medicine was related with the main active constituents, along with the origin and the harvesting time.

关键词： herb medicine fingerprint anticoccidial index spectrum-effect relationship

Stationary Solutions for a Generalized Kadomtsev-Petviashvili Equation in Bounded Domain

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Communications in Mathematical Research 2014年第3期30卷 273-283页

作者： zhang ke-yu XU JIA-FA Li Yong Department of Mathematics Qilu Normal University School of Mathematics Shandong University

In this work, we are mainly concerned with the existence of stationary solutions for a generalized Kadomtsev-Petviashvili equation in bounded domain of Rn. We utilize variational method and critical point theory to es... 详细信息

关键词： generalized Kadomtsev-Petviashvili equation stationary solution criticaI point theory variational method

Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China

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Chinese Geographical Science 2024年第3期34卷 519-532页

作者： HAN Nianlong yu Miao JIA Peihong zhang yucheng HU ke School of Geography and Tourism Huizhou UniversityHuizhou 516007China School of Public Administration Hainan Uni-versityHaikou 570228China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina School of Geographic Sciences and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Public Administration Nanjing Agricultural UniversityNanjing 210095China

Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the *** on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)*** dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their *** results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the ***,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural *** simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)*** maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened.

关键词： human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China

Lactate dehydrogenase:An important molecule involved in acetamizuril action against Eimeria tenella

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Journal of Integrative Agriculture 2020年第5期19卷 1332-1339页

作者： LIU Li-li FEI Chen-zhong DONG Hui zhang ke-yu Fu Jian-jun LI Tao XUE Fei-qun key Laboratory of Animal Parasitology Ministry of Agriculture/Shanghai Veterinary Research InstituteChinese Academy of Agricultural SciencesShanghai 200241P.R.China East China University of Science and Technology Shanghai 200237P.R.China

Lactate dehydrogenase(LDH),a vital enzyme in anaerobic glycolysis,is closely associated with the survival of *** studies of some parasites have shown that LDH exhibits unique physicochemical properties and molecular structures and may be an ideal potential target for diagnosis and drug *** this study,we aimed to investigate the effects of acetamizuril,a novel anticoccidial compound,on LDH in the second-generation merozoites of Eimeria tenella(mz-LDH).Quantitative real-time PCR,Western blot,immunofluorescence and enzyme activity assays were each applied to detect the changes of *** results indicated that the mRNA and protein levels of mz-LDH were reduced upon acetamizuril *** of mz-LDH demonstrated that considerable amount of mz-LDH was distributed around or in the nuclei of second-generation merozoites within the untreated group;in contrast,the acetamizuril-treated group had very low level of ***,LDH enzyme activity assay suggested that a decreased LDH enzyme activity in both cytoplasm and nucleus of merozoites in the acetamizuril-treated ***,the induced apoptosis in second-generation merozoites by the acetamizuril was evaluated by detecting caspase 3 activity,and acetamizuril was found to significantly increase caspase 3 *** above findings show that LDH may play an important role in the mediating the activity of acetamizuril against coccidiosis,and further investigation into this aspect might contribute to new light on the pathogenesis of *** during its interaction with acetamizuril.

关键词： acetamizuril lactate dehydrogenase E.tenella second-generation merozoites

Development of an enhanced online tritium monitoring system using plastic scintillation fiber array

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-11页

作者： Cheng, Wen-yu Deng, ke Zeng, You-Shi Liu, Wei zhang, Qin Chinese Acad Sci Shanghai Inst Appl Phys Shanghai 201800 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

Tritium, a radioactive nuclide discharged by nuclear power plants, poses challenges for removal. Continuous online monitoring of tritium in water is crucial for real-time radiation data, given its predominant existence in the environment as water. This paper presents the design, simulation, and development of a tritium monitoring device utilizing a plastic scintillation fiber (PSF) array. Experimental validation confirmed the device's detection efficiency and minimum detectable activity. The recorded detection efficiency of the device is 1.6x10-3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$1.6\times 10{-3}$$\end{document}, which exceeds the theoretically simulated value of 4x10-4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$4\times 10{-4}$$\end{document} by four times. Without shielding, the device can achieve a minimum detectable activity of 3165BqL-1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$3165\,\hbox {Bq}\,\hbox {L}{-1}$$\end{document} over a 1600-second measurement duration. According to simulation and experimental results, enhancing detection efficiency is possible by increasing the number and length of PSFs and implementing rigorous shielding measures. Additionally, reducing the diameter of PSFs can also improve detection efficiency. The minimum detectable activity of the device can be further reduced using the aforementioned methods.

关键词： Tritium Plastic scintillating fiber array Detector WATER SOIL

Small RNA existed in commercial reverse transcriptase： primary evidence of functional small RNAs

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Protein & Cell 2015年第1期6卷 1-5页

作者： Jie Xu Xi Chen Donghai Li Qun Chen Zhen Zhou Dongxia Hou Jin Wang Qipeng zhang ke Zen Chen-yu zhang Jiangsu Engineering Research Center for microRNA Biology and Biotechnology State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing 210093 China

SMALL RNA IN REVERSE TRANSCRIPTASE： TOO SMALL TO BE FOUND Significant background in no-template or no-primer RT-PCR is frequently noted. However, the underlying mechanism is still unclear. In this issue, Jie Xu and colleagues reveal that the com- mercial reverse transcriptases contain small RNAs. In AMV reverse transcriptase, they detected microRNAs derived from the virus host chick or other birds. This surprising finding at least partially explains the high background in some AMV reverse transcriptases based RT-PCR.

关键词： Reverse Transcriptase Small RNAs miRNA Profile miRNA Expression Profile Solexa Sequencing

Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries

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Nano-Micro Letters 2024年第2期16卷 154-164页

作者： Xin Chen yu zhang Chang Chen Huinan Li yuran Lin ke yu Caiyun Nan Chen Chen Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China Beijing key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875People’s Republic of China

Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at ***,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen *** one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox *** the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic ***,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery.

关键词： Atomically dispersed Open hollow structure Discharge product Lithium Oxygen battery