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恢复力的生态学内涵及量化方法研究综述

生态与农村环境学报 2024年第7期40卷 841-853页

作者：李艳鸽曹银贵严子循姚欣雨贺金鑫谭智元中国地质大学(北京)土地科学技术学院北京100083 中国地质大学(北京)自然文化研究院北京100083 自然资源部土地整治重点实验室北京100035 自然资源部黄土高原矿区土地复垦野外科学观测研究站北京100083

近几十年来,受自然灾害与人类活动的影响,全球生态系统严重退化,恢复力成为国际研究热点。本文以生态系统和社会-生态系统为研究对象,按照概念内涵—因素选取—量化方法的步骤对国内外恢复力研究进行系统综述。首先,以国内外现有理论与... 详细信息

近几十年来,受自然灾害与人类活动的影响,全球生态系统严重退化,恢复力成为国际研究热点。本文以生态系统和社会-生态系统为研究对象,按照概念内涵—因素选取—量化方法的步骤对国内外恢复力研究进行系统综述。首先,以国内外现有理论与研究为基础,梳理概括了国际基于概念内涵-提升原则的方法,以及国内常用的基于脆弱性和应对能力的方法,为量化因素的选取提供依据。其次,归纳了国内外主要量化方法,包括多因素综合评价法、指标替代法和模型法,并论述了每种方法适用范围及优缺点。通过对恢复力内涵及量化方法的综述,能够明晰国内外研究异同并跟进前沿进展,从而推进恢复力研究在我国国土空间生态保护修复评价和生态工程布局决策中的应用。

关键词：恢复力生态系统替代指标模型法综合评价法

Analysis of Genetic Diversity of Processing Apple Varieties

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Agricultural Sciences in China 2006年第10期5卷 745-750页

作者： SONG Ye ZHAI Heng yao yu-xin LI Ming DU yuan-peng College of Horticultural Science and Engineering Shandong Agricultural University Taian 271018 P.R.China

Genetic diversity of 18 processing apple varieties and two fresh varieties were evaluated using 12 simple sequence repeats （SSR） primer pairs previously identified in Malus domestica Borkh. A total of 87 alleles in 10 loci were detected using 10 polymorphic SSR markers selected within the range of 5-14 alleles per locus. All the 20 varieties could be distinguished using two primer pairs and they were divided into four groups using cluster analysis. The genetic similarity （GS） of groups analyzed using cluster analysis varied from 0.14 to 0.83. High acid variety Avrolles separated from other varieties with GS less than 0.42. The second group contained Longfeng and Dolgo from Northeast of China, the inherited genes of Chinese crab apple. The five cider varieties with high tannin contents, namely, Dabinette, Frequin rouge, Kermerrien, ***, and *** were clustered into the third group. The fourth group was mainly composed of 12 juice and fresh varieties. Principal coordinate analysis （PCO） also divided all the varieties into four groups. Juice and fresh apple varieties, Longfeng and Dolgo were clustered together, respectively, using both the analyses. Both the analyses showed there was much difference between cider and juice varieties, cider and fresh varieties, as well as Chinese crab apple and western European crab apple, whereas juice varieties and fresh varieties had a similar genetic background. The genetic diversity and differentiation could be sufficiently reflected by combining the two analytical methods.

关键词： processing apple varieties genetic diversity simple sequence repeats cluster analysis principal coordinate analysis

Rational modulation of electronic structure in PtAuCuNi alloys boosts efficient electrocatalytic ethanol oxidation assisted with energy-saving hydrogen evolution

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Journal of Energy Chemistry 2024年第6期93卷 557-567,I0014页

作者： Hu yao Yinan Zheng xin yu Songjie Hu Baolian Su Xiaohui Guo Key Lab of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education The College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710069ShaanxiChina Department of Inorganic Chemistry University of NamurBruxellesB-5000 NamurBelgium

Compared to conventional electrocatalytic water splitting,electrocatalytic ethanol oxidation reaction(EOR)along with hydrogen production is considered a more energy-efficient ***,we prepared a type of novel quaternary alloy catalyst(PtAuCuNi@NF)that exhibits excellent activity for EOR(0.215 V at 10 mA cm^(-2))and hydrogen evolution reaction(HER)(7 mV at 10 mA cm^(-2)).Experimental results demonstrated that both Cu and Ni modulated the electronic environment around Pt and *** electron-rich active center facilitates the rapid adsorption and dissociation of reactants and intermediates for both EOR and ***,in the ethanol-assisted overall water splitting(E-OWS),a current density of 10 mA cm^(-2)was achieved at 0.28 ***,an advanced acid-base self-powered system(A-Bsps)that can achieve a self-powered voltage of 0.59 V was ***,the self-driven hydrogen production with zero external power supply was realized by integrating A-Bsps with the E-OWS *** interesting results can provide a feasible strategy for designing and developing advanced nanoalloy-based materials for clean energy integration and use in various fields.

关键词： Pt-based alloy Electronic structure Ethanol oxidation Self-powered system Overall water splitting

EPC总承包项目中配电系统设计优化创效研究

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建筑技术开发 2024年第10期51卷 83-86页

作者：郭小晴姚欣雨武峡聂其林中建二局第三建筑工程有限公司北京100070

在EPC总承包项目中,设计阶段对项目工程质量、工程造价有着重要影响。针对EPC项目配电系统设计的优化创效实施方案,从主电源方案、变压器选型、柴油发电机选型、配电干线系统、干线电缆选择等5个方面展开技术方案对比及经济性比选,对实... 详细信息

在EPC总承包项目中,设计阶段对项目工程质量、工程造价有着重要影响。针对EPC项目配电系统设计的优化创效实施方案,从主电源方案、变压器选型、柴油发电机选型、配电干线系统、干线电缆选择等5个方面展开技术方案对比及经济性比选,对实际工程案例进行阐述与分析,为其他EPC工程总承包项目的电气专业设计优化创效提供优化方向及创效要点。

关键词： EPC总承包项目电气工程配电系统设计优化

Dissolution kinetics and reaction mechanism of Al_(2)O_(3) in molten CaF_(2)-CaO-Al_(2)O_(3) slag

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Journal of Iron and Steel Research International 2024年第4期31卷 861-869页

作者： yao-xin Du Yan-wu Dong Zhou-hua Jiang Ganna Stovpchenko yu-shuo Li Jun Huang xin-wei Wang yu-xiao Liu School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Ecological Metallurgy of Multimetallic Mineral Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina E.O.Paton Electric Welding Institute of the National Academy of Science of Ukraine Kiev 03115Ukraine

The dissolution behavior of Al_(2)O_(3) in molten CaF_(2)-CaO-Al_(2)O_(3) slag,a basic slag system of electroslag remelting process,was investigated by rotating cylinder method using corundum rods to simulate Al_(2)O_(3) inclusions in *** experimental results show that the dissolution rate of Al_(2)O_(3);rods in CaF_(2)-CaO-Al_(2)O_(3) slag increases with the increase in rotating speed and temperature,and the rate-controlling step is the mass transfer in the *** dissolution rate of Al_(2)O,in CaF_(2)-CaO-Al_(2)O_(3) slag increases with the increase in the ratio of CaO to Al_(2)O_(3),which is due to the increase in dissolution driving force and the decrease in slag *** apparent activation energy of the mass transfer of AlOs in slag C is calculated to be 222.86 kJ mol^(-1).During the dissolution of Al_(2)0,inclusions in the slag,it reacts with F in liquid slag at first,then reacts with CaO to form the intermediate compounds of xCaO-yAl_(2)O_(3) system,and finally dissolves in molten *** dissolution rate of Al_(2)O_(3) inclusions in CaF_(2)-CaO-Al_(2)O_(3) slag for electroslag remelting is positively correlated with the ratio of the dissolution driving force and slag viscosity,and the correlation coeficient is 2.487×10^(-11).

关键词： Inclusion Electroslag remelting Mass transfer:Dissolution rate-Dissolution driving force

Occurrence of viable but non-culturable(VBNC)pathogenic bacteria in tap water of public places

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 115-129页

作者： Lizheng Guo xinyan Xiao Kassim Chabi Yiting Zhang Jingjing Li Su yao xin yu China National Research Institute of Food and Fermentation Industries Co. Ltd.China Center of Industrial Culture CollectionBeijing 100015China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Environment&Ecology Xiamen UniversityXiamen 361102China

Viable but non-culturable(VBNC)bacteria have been detected in source water and effluent of drinking water treatment processes,leading to significant underestimation of viable cell *** information exists on VBNC bacteria in tap water,particularly in public *** address this gap,a comprehensive nine-month study was conducted in a major city in south-eastern China,using culture-based and quantitative PCR with propidium monoazide(PMA)dye ***-five samples were collected from five representative public places(railway station,campus,hospital,shopping mall,and institution).The findings revealed that culturable bacteria represented only 0–17.51%of the viable 16S rRNA genes,suggesting that the majority of viable bacteria existed in an uncultured or VBNC ***,opportunistic pathogens such as Escherichia coli,Enterococcus faecalis,Pseudomonas aeruginosa,Salmonella sp.,and Shigella *** primarily detected as VBNC cells,with concentrations ranging from 1.03×10^(0)to 3.01×10^(3),1.20×10^(0)to 1.42×10^(2),1.32×10^(0)to 8.82×10^(0),1.00×10^(0)to 6.71×10^(1),and 2.07×10^(0)to 1.93×10^(2)cell equivalent/100 mL,*** *** was observed in tap water after prolonged stagnation,indicating potential risks associated with bacterial *** and temporal factors accounted for 17.1%and 26.0%,respectively,of the variation in tap water community structure during the sampling period,as revealed by 16S rRNA amplicon *** study provides quantitative insights into the occurrence of VBNC bacteria in tap water and highlights the need for more sensitive monitoring methods and microbial control techniques to enhance tap water safety in public locations.

关键词： VBNC Pathogenic bacteria PMA treatment Public tap water Community structure

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： xin-Ru Wang Bao-Zhi Pan yu-Hang Guo Qing-Hui Wang yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

Polyphenolic Compound and the Degree of Browning in Processing Apple Varieties

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Agricultural Sciences in China 2007年第5期6卷 607-612页

作者： SONG Ye yao yu-xin ZHAI Heng DU yuan-peng CHEN Feng WEI Shu-wei College of Horticulture Science and Engineering Shandong Agricultural University Taian 271018 P.R.China Jinan Fruit Research Institute All China Federation of Supply and Marketing Cooperatives Jinan 250014 P.R. China State Key Laboratory of Crop Biology Shandong Agricultural University Taian 271018 P.R. China

Polyphenolic compound in processing apple （Malus domestica Borkh.） varieties and the relationship between polyphenol content and enzymatic browning were studied to provide reference for raw material selection and processing method optimization. The content of polyphenol compound in 10 processing apple varieties （4 cider and 6 juice varieties） were analyzed using the Folin-Ciocalteu method and HPLC. The degree of browning and the activities of polyphenol oxidase were also studied. The content and proportion of the polyphenol varied depending on the variety. Bitter varieties globally showed a higher polyphenol concentration than sweet or acid varieties. Proanthocyanidins, chlorogenic acid, （＋）-catechin, （-）-epicatechin were high-concentrated polyphenols in apple fruits. Phloridzin, the unique polyphenol of apple, was abundant in the bitter variety Frequin rouge fruit. Total polyphenols, proanthocyanidins, （＋）-catechin, and phloridzin had higher correlations with browning. The correlation was low between chlorogenic acid and browning. The polyphenolic profiles were correlated with the apple types. Cider apples contained more polyphenol than juice apple varieties. The content of flavan-3-ol has a close relationship with fruit browning.

关键词： apple processing varieties polyphenolic compounds browning polyphenol oxidase

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： yao Pan Xiaofeng Sun Wei Zhao xin Li yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power