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Controlling Three-Step and Five-Step Spin Transitions by Polymorphism in an Fe^(Ⅲ) Spin Crossover Complex

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Chinese Journal of Chemistry 2024年第8期42卷 879-886页

作者： Yingying Wu shuang Peng Ziyi Zhang Yue Gao Guangyan Xu Jingwei Dai Zhao-Yang li Masahiro Yamashita School of Materials Science and Engineering Nankai University38 Tongyan RoadHaihe Educational ParkTianjin300350 China State Key Laboratory of Medicinal Chemical Biology Nankai UniversityTianjin300071 China Department of Chemistry Graduate School of ScienceTohoku UniversitySendai980-8578 Japan

Comprehensive Summary,Regulating spin crossover(SCO)behavior,especially controlling the spin transition steps,is an important scientific issue,mainly because people aim to control spin bistability and ***,SCO bistability can be regulated by changing the ligand-modifying species,non-coordinated anions,guest molecules,and metal-ion ***,the control of multistability is extremely challenging,especially in Fe(iii)SCO ***,we report that[Feiii(H-5-Br-thsa)(5-Br-thsa)]·H2O(5-Br-thsa=(5-bromo-2-hydroxybenzylidene)hydrazinecarbothioamide),a compound we have reported before,exists in two polymorphic forms:polymorph 1 exhibits three-step SCO,and polymorph 2 shows five-step SCO,with multi-step SCO behavior effectively regulated by *** to single-crystal and powder X-ray diffractometry,polymorphs 1 and 2 crystallize in different space groups during their spin transitions,with two-step symmetry breaking observed(Pbcn→Pnc2→Pbcn for polymorph 1;P21/n→Pn→P21/n for polymorph 2).We realized that the behavior of these two polymorphs depends significantly on the structure,including(i)the average Fe—N bond distance,(ii)deformation of octahedral Feiii atoms,and(iii)distinct crystal packing,which account for the large differences observed in magnetic properties.

关键词： Spin crossover Multi-step spin transition Symmetry breaking Polymorphism Magnetic property

Extensive identification of landslide boundaries using remote sensing images and deep learning method

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China Geology 2024年第2期7卷 277-290页

作者： Chang-dong li Peng-fei Feng Xi-hui Jiang shuang Zhang Jie Meng Bing-chen li Faculty of Engineering China University of GeoscienceWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China School of Mechanical Engineering and Electronic information China University of GeosciencesWuhan 430074China College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China

The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster *** is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency ***,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary *** SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic *** exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model *** experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MioU values between 0.8and 0.9;while 52 images with MioU values exceeding 0.9,which exceeds the identification accuracy of existing *** work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.

关键词： Geohazard Landslide boundary detection Remote sensing image Deep learning model Steep slope Large annual rainfall Human settlements infrastructure Agricultural land Eastern Tibetan Plateau Geological hazards survey engineering

Characteristics and genetic mechanism of the Mesoproterozoic rift system,Ordos Basin,China

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Energy Geoscience 2024年第1期5卷 141-152页

作者： Meng li Xiangbin Yan Wei Zhang Yuanling Guo Chaoying liu lingling Fan shuang Yang Petroleum Exploration and Production Research institute SINOPECBeijing100083China Exploration and Development Research institute SINOPEC North China CompanyZhengzhouHenan450006China

The Mesoproterozoic rifts are developed in the Ordos Basin located in the western margin of the North China *** on the latest 3D seismic data and previous research results,this study intends to discuss the zonal differential deformation characteristics and genetic mechanism of the Mesoproterozoic rifts in the Ordos ***-trending rifts are developed in the Mesoproterozoic in the south-central Ordos Basin,the main part of which are located near the western margin of the North China ***-trending rifts are developed in the north of the basin,while NW-NNW rifts in the Mesoproterozoic in Hangjinqi *** genetic mechanism of the Mesoproterozoic rifts is related to regional extensional stress field,plate boundary conditions and internal preexisting *** main extensional stress direction strikes NWW-SSE(120°)in the western margin of the North China Plate,based on the forward rift trend of the northern *** Hangjinqi area,the reactivation of the existing NWtrending Wulansu fault and NW-NW-trending Daolao fault,results in dextral shear stress *** boundary between the western margin of the North China Plate and its adjacent plates forms a nearly NS-trending preexisting basement tectonic belt,which intersects with the NWW-SSE(120°)extensional stress at an acute angle of 60°.Therefore,the western margin of the North China Plate is formed by oblique normal faults under oblique *** to the long time span of Columbia Supercontinent breakup(1.8e1.6 Ga),the oblique rift in the south-central Ordos Basin is formed under the continuous oblique extension at the western margin of the North China Plate.

关键词： Columbia Supercontinent Ordos Basin Rift system Mesoproterozoic Genetic mechanism

Clinical characteristics of acute non-varicose upper gastrointestinal bleeding and the effect of endoscopic hemostasis

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World Journal of Clinical Cases 2024年第9期12卷 1597-1605页

作者： Xiao-Juan Wang Yu-Peng Shi li Wang Ya-Ni li li-Juan Xu Yue Zhang shuang Han Department of Gastroenterology Honghui Hospital Affiliated to Medicine College of Xi’an Jiaotong UniversityXi'an 710054Shaanxi ProvinceChina

BACKGROUND Acute non-variceal upper gastrointestinal bleeding(ANVUGiB)constitutes a prevalent emergency within Gastroenterology,encompassing 80%-90%of all gastrointestinal hemorrhage *** condition is distinguished by its abrupt onset,swift progression,and notably elevated mortality *** To gather clinical data from patients with ANVUGiB at our hospital in order to elucidate the clinical characteristics specific to our institution and analyze the therapeutic effectiveness of endoscopic *** We retrospectively retrieved the records of 532 patients diagnosed with ANVUGiB by endoscopy at our hospital between March 2021 and March 2023,utilizing our medical record *** pertaining to general patient information,etiological factors,disease outcomes,and other relevant variables were meticulously collected and *** Among the 532 patients diagnosed with ANVUGiB,the male-to-female ratio was 2.91:1,with a higher prevalence among ***,43.6%of patients presented with black stool as their primary complaint,while 27.4%had hematemesis as their initial *** admission,17%of patients exhibited both hematemesis and black stool,while most ANVUGiB patients primarily complained of overt gastrointestinal *** routine blood examinations at admission revealed that 75.8%of patients had anemia,with 63.4%experiencing moderate to severe anemia,and 1.5%having extremely severe anemia(hemoglobinith regard to etiology,53.2%of patients experienced bleeding without a definitive trigger,24.2%had a history of using gastric mucosa-irritating medications,24.2%developed bleeding after alcohol consumption,2.8%attributed it to improper diet,1.7%to emotional excitement,and 2.3%to fatigue preceding the bleeding ***-induced ANVUGiB was more prevalent in the elderly than middle-aged and young individuals,while bleeding due to alcohol consumption showed the opposite ***,diet-related bleeding was more common

关键词： Acute non-varicose upper gastrointestinal bleeding Clinical characteristics Cause of disease Endoscopic homeostatic therapy

Prediction and quantification of effective gas source rocks in a lacustrine basin: Western Depression in the liaohe Subbasin, China

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Petroleum Science 2024年第4期21卷 2218-2239页

作者： Si-Bo Yang Mei-Jun li Hong Xiao Fang-Zheng Wang Guo-Gang Cai shuang-Quan Huang State Key Laboratory of Petroleum Resources and Prospecting College of Geosciences China University of Petroleum China University of Petroleum-Beijing at Karamay College of Petroleum Research institute of Petroleum Exploration and Development Liaohe Oilfield Company PetroChina

Due to limited data on the geochemical properties of natural gas, estimations are needed for the effective gas source rock in evaluating gas potential. However, the pronounced heterogeneity of mudstones in lacustrine successions complicates the prediction of the presence and geochemical characteristics of gas source rocks. in this paper, the liaohe Subbasin of Northeast China is used as an example to construct a practical methodology for locating effective gas source rocks in typical lacustrine basins. Three types of gas source rocks, microbial, oil-type, and coal-type, were distinguished according to the different genetic types of their natural gas. A practical three-dimensional geological model was developed, refined, and applied to determine the spatial distribution of the mudstones in the Western Depression of the liaohe Subbasin and to describe the geochemical characteristics(the abundance, type, and maturation levels of the organic matter). Application of the model in the subbasin indicates that the sedimentary facies have led to heterogeneity in the mudstones, particularly with respect to organic matter types. The effective gas source rock model constructed for the Western Depression shows that the upper sequence(SQ2) of the Fourth member(Mbr 4) of the Eocene Shahejie Formation(Fm) and the lower and middle sequences(SQ3 and SQ4) of the Third member(Mbr 3) form the principal gas-generating interval. The total volume of effective gas source rocks is estimated to be 586 km3. The effective microbial, oil-type, and coal-type gas source rocks are primarily found in the shallow western slope, the central sags, and the eastern slope of the Western Depression, respectively. This study provides a practical approach for more accurately identifying the occurrence and geochemical characteristics of effective natural gas source rocks, enabling a precise quantitative estimation of natural gas reserves.

关键词： Effective gas source rock 3D geological modeling Spatial distribution Geochemical characteristics Lacustrine rift basin

A new Keggin-type polyoxometallate-based bifunctional catalyst for trace detection and pH-universal photodegradation of phenol

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Chinese Chemical Letters 2024年第8期35卷 335-340页

作者： shuang li Jiayu Sun Guocheng liu Shuo Zhang Zhong Zhang Xiuli Wang College of Chemistry and Materials Engineering Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar CellBohai UniversityJinzhou 121013China

The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human ***,it is very important to develop a con-venient and effective method to detect and degrade phenolic ***,we report a new keggin-type polyoxometallate-based metal-organic complex self-assembled under solvothermal condition,{[Cu(dap)(3-PA)]4(SiW_(12)O_(40))(H_(2)O)_(2)}·2H_(2)O(1,dap=1,2-diaminopropane,3-HPA=3-pyridineacrylic acid).1 shows an interesting 1D ladder-like *** a bifunctional catalyst,1 can be employed as a colori-metric sensor toward phenol with the relatively low detection limit(LOD)of 0.36μmol/L(S/N=3)in the wide range(0.001-0.1 mmol/L).The title colorimetric sensor is applied to determine phenol in various water environment with good recoveries ranging from 95%-105%.in addition,1 also exhibits excellent photocatalytic degradation toward phenol under visible light with the highest removal efficiency at 96%for 100 min and wide pH *** selectivity,stability and reliability of the detection of 1 towards phenol,as well as the detection for 4-chlorophenol,o-cresol,4-nitrophenol and phloroglucinol were ***,the photocatalytic reaction kinetics and the mechanisms of photodegradation of phenol were also investigated in detail.

关键词： POM-based metal-organic complex Bifunctional catalyst Phenolic colorimetric sensor Low detection limit pH-universal photocatalysis Photodegraded phenol

lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

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Chinese Journal of Chemical Engineering 2024年第3期67卷 238-246页

作者： Yong-Yi Zeng Xin-Yi Xu Jin-Xuan Xie Wen-li Chen Lan liu Xin-Jian Yin Bi-shuang Chen School of Marine Sciences Sun Yat-Sen UniversityZhuhai 519080China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional ***,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its *** this study,an engineered strain Escherichia coli(***)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into *** potential of *** BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process *** a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light *** selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) *** the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based ***,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

关键词： Alkane-based biodiesel Renewable biomass Co-overexpression lipase Photodecarboxylase

Quantifying the impact of earthquakes and geological factors on spatial heterogeneity of debris-flow prone areas:A case study in the Hengduan Mountains

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Journal of Mountain Science 2024年第5期21卷 1522-1533页

作者： HU Xudong SHEN Yitong HU Kaiheng XU Wennian liU Daxiang HE Songtang GAO Jiazhen WEi li liU shuang Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials(China Three Gorges University) Yichang 443002China Hubei Key Laboratory of Disaster Prevention and Mitigation(China Three Gorges University) Yichang 443002China College of Civil Engineering and Architecture China Three Gorges UniversityYichang 443002China Shanghai investigation Design&Research Institute Co.Ltd.Shanghai 200335China Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of SciencesChengdu 610041China institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Wuhan Polytechnic Wuhan 430074China

Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the Hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debrisflow prone areas. Results showed that the application of GiS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debrisflow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m-2500 m elevation difference, 25°-30° average slope, and 0.13-0.15 land use index is the most favorable conditions for debris-flow occurrence;The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies.

关键词： debris-flow prone areas causal factors GiS-based method spatial heterogeneity Hengduan Mountains

Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: implications for the Ediacaran microbial mound construction and hydrocarbon exploration

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Petroleum Science 2024年第2期21卷 806-822页

作者： Jin-Min Song Xin Jin Zhong Luo Shu-Gen liu Shao-Bo liu Xing-Zhi Ma Zhi-Wu li Xue-Song Lu ling-li Zhao Ke-Ran li Jia-Xin Ren li-Zhou Tian Hao-shuang Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina PetroChina Research institute of Petroleum Exploration and Development Beijing100083China Xihua University Chengdu610039SichuanChina

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain late

关键词： Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications