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Influencing factors and significance of organic and inorganic nitrogen isotopic compositions in lacustrine sedimentary rocks

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Geoscience Frontiers 2023年第2期14卷 27-39页

作者： Juan Chen Jianfa Chen Lipeng Yao Qingyong Luo Shengbao Shi Jianping Chen Lei Zhu Zeya Chen Key Laboratory of Environment Change and Resources Use in beibu gulf(Nanning Normal university) Ministry of EducationNanning 530001China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China

Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous Qingshankou Formation(QF,86–92 Ma)in Songliao basins,by evaluating the organic and inorganic nitrogen isotopic compositions rather than only organic or bulk nitrogen isotopic *** results indicate that the nitrogen isotope values of bulk rock(δ^(15)N_(bulk))in the non-metamorphic stage are significantly different from that of kerogen,which challenge the conceptual framework of sedimentary nitrogen isotope ***δ^(15)N_(bulk)from the YF and QF were lower than their respective the nitrogen isotope values of kerogen(δ^(15)N_(ker)),with offsets up to5.1‰,which have the inverse relationship for the metamorphosed *** evolution did not significantly modify the d15N of bulk rock and *** d15N of sediments from the YF(δ^(15)N_(bulk),1.6‰–5.6‰)were lower than that of rock from the QF(δ^(15)N_(bulk),10.2‰–15.3‰).The nitrogen isotope values of silicate incorporated nitrogen(δ^(15)N_(sil))were slightly lower than those of the d15Nker in the YF and obviously lower for the *** fact that different nitrogen cycles occur in the YF and QF due to the different depositional redox conditions leads to different isotopic *** YF water environment dominated by oxic conditions is not conducive to the occurrence of denitrification and anammox,and no abundant N2 loss leads to the relatively lightδ^(15)N_(bulk).In the stratified water for the QF,redox transition zone promotes denitrification and anammox,resulting in the heavyδ^(15)N_(bulk)of rock and promotes the DNRA,resulting in heavyδ^(15)N_(ker)and lowδ^(15)N_(sil).

关键词： Nitrogen isotopes Bulk rock Kerogen Extracted organic matter Thermal maturation Nitrogen biogeochemical cycle

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Modelling spatial variation in the treatment costs of nonpoint source pollution in mountainous regions of southwest China

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Journal of Mountain Science 2019年第8期16卷 1901-1912页

作者： LIU Ju FU Bin ZHANG Cheng-hu WANG Yu-kuan Key Laboratory of Environment Change and Resources Use in beibu gulf(Ministry of Education) Key Laboratory of Earth Surface Process and Intelligent SimulationNanning Normal UniversityNanning 530001China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

Non-point source(NPS) pollution is considered to be one of the main threats of the aquatic environment. Mountainous regions are particularly important water sources for urban areas. The various driving factors of NPS pollution such as terrain, precipitation, and vegetation type in mountainous regions show clear spatial heterogeneity. Consequently, the management systems required for NPS pollution in mountainous regions are complex. In this study, we developed a framework to estimate and map the treatment costs for NPS pollution in mountainous regions and applied this method in Baoxing County, a typical mountainous county in Sichuan Province of southwest China. The export levels of total nitrogen(TN) and total phosphorus(TP) in Baoxing County were estimated using the water purification model in InVEST(Itegrated Valuation of Ecosystem Services and Tradeoffs) tool. NPS pollutant treatment costs were calculated based on the level of pollutants exports, water yield, water quality targets, and treatment costs of NPS pollutants per unit mass. The results show that at the watershed level the amounts of TN and TP exported in Baoxing County were below threshold limits. However, at the sub-watershed level, TN and TP excesses of 291.64 and 2.96 tons per year were found, respectively, with mean TN and TP treatment costs of 6.58 US$/hm^2 and 0.35 US$/hm^2. Appraising pollution treatment cost intuitively reflects the overall expenditure in NPS pollution reduction from an economic perspective. This study provides a foundation for the implementation of Payment for Ecosystem Service(PES) and the prevention and control of NPS pollution.

关键词： Nonpoint source pollution Water treatment cost Water purification model InVEST Tool Export coefficient Spatial variation

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Transcriptome Analysis of the Digestive Tract of Tachypleus tridentatus and Carcinoscorpius rotundicauda

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Journal of Ocean university of China 2022年第3期21卷 591-600页

作者： LI Yuhong KWAN Kit Yue LI Sansu LIU Yingchun WENG Bosen HUANG Wenshu WENG Zhaohong Department of Environmental Science and Engineering Huaqiao UniversityXiamen361021China College of Marine Sciences Beibu Gulf UniversityQinzhou535011China School of Biomedical Sciences Huaqiao UniversityXiamen361021China School of Basic Medical Sciences Fujian Medical UniversityFuzhou350108China Fisheries College Jimei UniversityXiamen361021China

Transcriptome assemblies for the stomach,midgut,and fecal mucosa of Tachypleus tridentatus and Carcinoscorpius rotundicauda are reported for the first time in this *** assembly resulted in 373069 unigenes with an N50 of 1314,while transcriptome assembly resulted in 736378 unigenes and an N50 of *** annotated unigenes showed the highest similarity to fishes,amphibians,and reptiles,with most unigenes closely related to metabolism,translation,biogenesis,signal transduction,energy production,immune response,and ***(4768)were mapped to KEGG pathways,and the most enriched pathways were involved in translation,environmental information signal processing,metabolism,endocrine system,immune system,nervous system,and varying *** 65889,2001,and 7162 differentially expressed genes(DEGs)were identified in the stomach,midgut,and fecal mucosa between the two horseshoe crab species,*** with ***,99.95%of the DEGs in the *** stomach were down-regulated,while 99.97%of the DEGs of *** fecal mucosa and 55.42%of the DEGs of the *** midgut were *** midgut DEGs were involved in hydrolase activity,protein metabolism,and cell cytoplasm,while most stomach and fecal mucosa DEGs were involved in catalytic activity and primary metabolic *** stomach DEGs were assigned to the cellular component in cellular macromolecular complexes,while most fecal mucosa DEGs were assigned to the cellular component in cell and cell *** results will benefit the investigation of the molecular mechanisms of the digestive tract related to the feeding habits and environmental traces of horseshoe crabs.

关键词： transcriptome digestive tract Tachypleus tridentatus Carcinoscorpius rotundicauda differentially expressed genes(DEGs)

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Preparation and Performance of a Fluorine-Free and Alkali-Free Liquid Accelerator for Shotcrete

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Journal of Renewable Materials 2021年第11期9卷 2001-2013页

作者： Jianbing Zhang Rongjin Liu Siyuan Fu Tianyu Gao Zhongfei Zhang College of Material Science and Engineering Guilin University of TechnologyGuilin541004China Guangxi Engineering and Technology Center for Utilization of Industrial Waste Residue in Building Materials Guilin541004China Guangxi beibu gulf Engineering Research Center for Green Marine Materials Guilin541004China

Based on aluminum sulfate,a fluorine-free and alkali-free liquid accelerator(FF-AF-A)was prepared in this *** setting time and compressive strength of three cement types with different FF-AF-A dosages were fully *** compatibility of the FF-AF-A with the superplasticizers were also investigated,and the early hydration behavior and morphology of the hydration products of reference cement paste with the FF-AF-A were explored by hydration heat,X-ray diffractometry(XRD),and scanning electron microscopy(SEM).Test results indicated that adding the FF-AF-A at 8 wt%of the cement weight resulted in 2 min 35 s initial setting time and 6 min 30 s final setting *** 1-day compressive strength of the cement mortar with 8 wt%of FF-AF-A reached 13.5 MPa,which represents an increase of 35%as compared to the strength of cement mortar without the FF-AF-A,and the 28-day compressive strength ratio was 119%.In addition,the FF-AF-A also showed good compatibility with different superplasticizer *** results show that,when the FF-AF-A was added to the cement paste,it promoted the formation of ettringite crystals due to the aluminum ions(Al^(3+))and sulfate ions(SO_(4)^(2-))reacted with gypsum in the cement,as well as promoted the hydration of tricalcium aluminate(C_(3)A)and tricalcium silicate(C3S)leading to the overall structure becomes more *** a consequence,the hydration heat rate of the cement sharply increased,the cement paste setting time is shortened,and the compressive strength of cement mortar is improved.

关键词： Shotcrete alkali-free liquid accelerator setting time compressive strength mechanism

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STGI:a spatio-temporal grid index model for marine big data

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Big Earth Data 2020年第4期4卷 435-450页

作者： Tengteng Qu Lizhe Wang Jian Yu Jining Yan Guilin Xu Meng Li Chengqi Cheng Kaihua Hou Bo Chen College of Engineering Peking UniversityBeijingChina School of Computer Science China University of GeosciencesWuhanChina Key Laboratory of Environmental Evolution and Resource Utilization in beibu gulf Nanning Normal UniversityNanningChina Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhenChina

Marine big data are characterized by a large amount and complex structures,which bring great challenges to data management and *** on the GeoSOT Grid Code and the composite index structure of the MongoDB database,this paper proposes a spatio-temporal grid index model(STGI)for efficient optimized query of marine big data.A spatio-temporal secondary index is created on the spatial code and time code columns to build a composite index in the MongoDB database used for the storage of massive marine *** comparative experiments demonstrate that the retrieval efficiency adopting the STGI approach is increased by more than two to three times compared with other index *** theoretical analysis and experimental verification,the conclusion could be achieved that the STGI model is quite suitable for retrieving large-scale spatial data with low time frequency,such as marine big data.

关键词： GeoSOT spatio-temporal grid index model marine big data MongoDB

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Notes on Rings with Strong 2-Sum Property

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Algebra Colloquium 2020年第4期27卷 821-830页

作者： Yu Li Huadong Su Gaohua Tang Yiqiang Zhou School of Mathematics and Statistics Guangxi Normal University GuilinGuangxi 541004China School of Mathematics and Statistics Southwest University Chongqing 400715China School of Mathematics and Statistics Nanning Normal University Nanning 530001China School of Sciences Beibu Gulf UniversityQinzhouGuangxi 535011China Department of Mathematics and Statistics Memorial university of Newfoundland St.John'sCanada

A ring is said to satisfy the strong 2-sum property if every element is a sum of two commuting *** this note,we present some sufficient or necessary conditions for the matrix ring over a commutative local ring to have... 详细信息

关键词： (strong)2-sum property involution property unit matrix ring local ring

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Total Maximum Allocated Loads on Stoichiometry of Nitrogen and Identification of Critical Form in Jiaozhou Bay, China

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Journal of Ocean university of China 2020年第3期19卷 622-632页

作者： LIN Guohong SONG Xianli LU Dongliang LI Keqiang LIANG Shengkang WANG Xiulin Key Laboratory of Marine Chemistry Theory and Technology(Ocean university of China) Ministry of EducationQingdao 266100China College of Material Science and Engineering Qingdao UniversityQingdao 266100China Marine Biology Institute of Shandong Province Qingdao 266104China Guangxi Key Laboratory of Marine Disaster in the beibu gulf Qinzhou UniversityQinzhou 535099China

Total pollutant load control management for total dissolved nitrogen(TDN) is an urgent task required to gain a good water quality status in Jiaozhou Bay(JZB), China. In this paper, the stoichiometry of multiform TDN on land-ocean interactions associated with marine biogeochemical reaction(LOIMBR) was studied by modeling the load-response relationship based on a three-dimensional water quality model of nitrogen in JZB. The results showed that the stoichiometry on LOIMBR of dissolved organic nitrogen(DON), NO3-N and NH4-N was 3:1:1, with one-third of the contribution on the concentration of dissolved inorganic nitrogen(DIN) in JZB for the land-based DON loads to DIN loads. Based on the stoichiometric relationship of nitrogen forms, the total maximum allocated load(TMAL) of equivalent TDN(ETDN) was approximately 5300 t a^-1 in JZB, equivalent to the TMAL of 5700, 5800 and 15600 t a^-1 for NH4-N, NO3-N and DON, respectively. According to the loads of ETDN, there were four outfalls overloaded in JZB in 2015, which lie in the head of the bay. In the four overloaded outfalls, besides NO3-N, NH4-N was the critical nitrogen control form for Moshui River, while DON for Dagu River and Haibo River. The results of numerical experiments further showed that JZB will achieve good water quality after 7 years by implementation of the 'different emission reduction' based on TMAL of ETDN, which is significantly better than 'equal percent removal'.

关键词： total dissolved nitrogen water quality stoichiometry total maximum allocated load Jiaozhou Bay

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A New Species of Nidirana(Anura,Ranidae)from Southern Guangxi,China

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Asian Herpetological Research 2022年第2期13卷 109-116页

作者： Weicai CHEN Wanxiao PENG Peng LI Youjun LIU Key Laboratory of Environment Change and Resources Use in beibu gulf Ministry of Education Nanning Normal UniversityNanning 530001GuangxiChina Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation Nanning Normal UniversityNanning 530001GuangxiChina Shiwandashan National Nature Reserve Fangchenggang 538000GuangxiChina

A new music frog,Nidirana shiwandashanensis ***.,is described from Shiwandashan National Nature Reserve,Shangsi County,Guangxi,*** analysis based on mtDNA sequences indica tes tha t the new species is closest to ***,*** *** from its congeners based on morphological characters,molecular data,and *** advertisement calls are comprised of 6–8 double notes,which are distinct from its sister taxon,***,the new species occurs in the evergreen forest at Shiwandashan National Nature Reserve between 500–600 m a.s.l.

关键词： bioacoustics morphology Nidirana phylogeny

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Agricultural opportunity costs assessment based on planting suitability:a case study in a mountain county in southwest China

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Journal of Mountain Science 2017年第12期14卷 2568-2580页

作者： liu ju fu bin wang yu-kuan lu ya-feng xu pei institute of mountain hazards and environment chinese academy of sciencesChengdu 610041China key laboratory of environment change and resources use in beibu gulf(guangxi teachers education university) ministry of educationNanning 530001China wanzhou key regional ecology and environment monitoring station Chongqing 404020China

Payment for ecosystem services(PES) has become an increasingly popular means of ecosystem conservation. Opportunity cost is an important factor to increase the investment efficiency of PES ***, the distribution of opportunity cost is usually unclear in mountainous regions due to the obvious environment changes. In this study, we developed a framework to assess the distribution of agricultural opportunity costs in mountainous regions and applied this method to Baoxing County, a typical mountainous county in Sichuan Province of southwest China. Planting suitability of 17 crops was assessed based on agricultural statistics and natural conditions data within a GIS *** opportunity cost was quantified with a weighted summation of farmers' willingness to cultivate and each crop's opportunity cost. Finally,specific agricultural opportunity cost was obtained according to the spatial areas of the protection programs and land use status. The results showed that agricultural opportunity costs of PES in Baoxing County were estimated to be more than $30 million,with a mean of 400.85 $/ha. Agricultural opportunity costs in mountainous regions displayed some obvious spatial variation and areas with lower agricultural opportunity costs could be selected as priority areas for PES. Our findings revealed that the planting suitability evaluation can make agricultural opportunity costs mapping more reasonable. It will be helpful for the PES programs implementation in mountainous regions.

关键词： Opportunity cost Planting suitability Willingness to accept Ecosystem service Spatial variation Baoxing County

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Gonadal transcriptomic analysis and differentially expressed genes between the testes and ovaries in Trachinotus ovatus

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Aquaculture and Fisheries 2022年第1期7卷 31-39页

作者： Pingping He Peng Zhu Pinyuan Wei Xiaofei Zhuo Yuan Ma Xiaohan Chen Yong Lin Youhou Xu Hui Luo Jinxia Peng Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture Guangxi Academy of Fisheries SciencesNanning530021China beibu gulf university Qinzhou535000China College of Animal Science Southwest UniversityChongqing402460China

The Trachinotus ovatus is a popular aquaculture species in *** are no obvious morphological differences between male and female fish,even during maturity,prompting research studies on sex-related features of this *** examine sex determination-and gonadal development-related genes,we conducted transcriptome analysis of the ovaries and testes of ***.A total of 345,972,132 high-quality clean reads were obtained from 12 *** addition,28,137 gonad-expressed unigenes were obtained by mapping the clean reads to the *** reference genome.A total of 8,237 differentially expressed genes(DEGs)were identified between stage I ovaries and testes,including 3,235 testicular upregulated and 5,002 ovarian upregulated ***,13,448 DEGs were obtained between stage III ovarian and testicular libraries,including 7,576 testicular upregulated and 5,872 ovarian upregulated *** DEGs included some sex-determining genes such as sry,dmrt1,and *** between ovarian and testicular libraries were significantly enriched with KEGG pathways that are involved in gonadal development,sex determination,and gonadal ***,10 DEGs(seven testicular upregulated and three ovarian upregulated unigenes)were selected for quantitative real-time PCR *** genes(zinc-binding protein A33-like,pro-opiomelanocortin-like,leucine-rich repeat and transmembrane domain-containing protein 2-like,and forkhead boxC1)showed a specific testicular expression *** gonadally expressed as well as testicular and ovarian DEGs provide useful information for further research on the reproductive biology of ***.

关键词： Transcriptome Trachinotus ovatus Gonad High-throughput sequencing RT-qPCR

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