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黄土高原半干旱区典型流域土地利用变化及驱动因素研究

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甘肃林业科技 2024年第1期49卷 1-8页

作者：张亮孛永明李旭春王丽洁鱼海霞张立靖甘肃省定西市水土保持科学研究所甘肃定西743000

利用2000、2010、2020三期遥感影像资料,基于地统计学原理,从土地利用动态度、土地利用强度、土地利用类型相互转化程度入手,解译关川河流域长时序多期土地利用/覆被变化情况。结果表明,耕地、草地为关川河流域主要的土地利用变化类型,... 详细信息

利用2000、2010、2020三期遥感影像资料,基于地统计学原理,从土地利用动态度、土地利用强度、土地利用类型相互转化程度入手,解译关川河流域长时序多期土地利用/覆被变化情况。结果表明,耕地、草地为关川河流域主要的土地利用变化类型,各地类面积占比:耕地草地>灌木人造地表>林地>水体,耕地面积保持在69%左右,草地面积保持在25%以上,耕地、灌木地、水体面积在20年间分别减少3374.82hm^(2)、11318.17hm^(2)、103.62hm^(2),林地、草地、人造地表面积分别增加128.00hm^(2)、8765.59hm^(2)、5903.01hm^(2)。研究期后十年综合土地利用动态度明显高于前十年,增幅达79.9%,土地综合利用程度高。2000-2010年间,耕地和水体转出,林地、草地、灌木地、人造地表转入;2010-2020年间,耕地和灌木地转出,林地、草地、水体、人造地表转入。社会因素的驱动对关川河流域土地利用格局的演变效应显于自然因素。本研究旨在更好地处理人地关系,为治理流域水土流失、调整土地利用结构、发展当地经济及保护生态环境提供科学依据。

关键词：关川河流域土地利用变化特征主成分分析驱动机制

CmMYB3-like negatively regulates anthocyanin biosynthesis and flower color formation during the post-flowering stage in Chrysanthemum morifolium

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Horticultural Plant Journal 2024年第1期10卷 194-204页

作者： lijie Zhou Shenhui Liu Yiguang wang Yuxi wang Aiping Song Jiafu Jiang Sumei Chen Zhiyong Guan Fadi Chen State Key Laboratory of Crop Genetics and Germplasm Enhancement The Key Laboratory of LandscapingMinistry of Agriculture and Rural AffairsCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China

Color fading caused by a decrease in anthocyanin accumulation during the post-flowering stage significantly affects postharvest quality of chrysanthemum.However,the underlying mechanism by which anthocyanin accumulation decreases during the post-flowering stage still unclear,which greatly restricts design of molecular breeding in chrysanthemum.Here,a chrysanthemum SG7 R2R3 MYB transcription factor(TF),CmMYB3-like,was identified to have a function in regulating anthocyanin biosynthesis during the post-flowering stage.Quantitative real time PCR(qRT-PCR)assays showed that the expression of CmMYB3-like was gradually downregulated when anthocyanin content increased during the flowering stage and was significantly upregulated during the post-flowering stage.Genetic transformation of chrysanthemum and dual-luciferase assays in N.benthamiana leaves showed that CmMYB3-like suppressed anthocyanin accumulation by inhibiting the transcription of CmCHS and CmANS directly and that of CmF3H indirectly.However,overexpression or suppression of CmMYB3-like did not affect the biosynthesis of flavones or flavonols.Genetic transformation of chrysanthemum revealed that the overexpression of CmMYB3-like inhibited anthocyanin accumulation,but its suppression prevented the decrease in anthocyanin accumulation during the post-flowering stage.Our results revealed a crucial role of CmMYB3-like in regulating the color of petals during the post-flowering stage and provided a target gene for molecular design breeding to improve the postharvest quality of chrysanthemum.

关键词： Post-flowering stage Color fading Anthocyanins CmMYB3-like Chrysanthemum Molecular breeding

Enhancement of CH_(3)CO^(*) adsorption by editing d-orbital states of Pd to boost C–C bond cleavage of ethanol eletrooxidation

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Science China Chemistry 2024年第2期67卷 696-704页

作者： Yuchen Qin Fengqi wang Pei Liu Jinyu Ye Qian wang Yao wang Guangce Jiang lijie Liu Pengfang Zhang Xiaobiao Liu Xin Zheng Yunlai Ren Junjun Li Zhicheng Zhang College of Sciences Henan Agricultural UniversityZhengzhou450000China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin300072China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen361005China Department of Analysis Sinopec Engineering Group Luoyang R&D Center of TechnologyLuoyang471000China School of Chemical and Material Engineering Jiangnan UniversityWuxi214211China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology Liaocheng UniversityLiaocheng252000China

Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy density.However,the weak adsorption energy of CH_(3)CO^(*) on Pd restricts the C–C bond cleavage.Inspired by the molecular orbital theory,we proposed the d-state-editing strategy to construct more unoccupied d-states of Pd for the enhanced interaction with CH_(3)CO^(*) to break C–C bonds.As expected,the reduced number of e_g electrons and more unoccupied d-states of Pd successfully formed on as-prepared porous Rh Au–Pd Cu nanosheets(PNSs).Theoretical calculations show that the optimized d-states of Rh Au–Pd Cu PNS can effectively improve the adsorption of CH_(3)CO^(*) and drastically reduce the energy barrier of C–C bond cleavage,thus boosting the complete oxidation of ethanol.The charge ratio of C_1 pathway on Rh Au–Pd Cu PNSs is 51.5%,more than 2 times higher than that of Pd NSs.Our finding provides an innovative perspective for the design of highly-efficient noble-based electrocatalysts.

关键词： C–C bond cleavage CH_(3)CO^(*)adsorption unoccupied d-states ethanol oxidation reaction RhAu–PdCu porous nanosheets

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儿童的人博卡病毒感染研究进展

中华危重病急救医学 2023年第5期35卷 548-553页

作者：朱旭王丽杰中国医科大学附属盛京医院儿内科辽宁沈阳110004

人博卡病毒是2005年首次于呼吸道样本中检出的新的病原体。人博卡病毒可感染不同年龄段的人群,主要易感人群为儿童,尤以6~24个月的婴幼儿多见。不同地区的流行季节因气候和地理位置的差异有所不同,好发于秋冬季。人博卡病毒1型与呼吸系... 详细信息

人博卡病毒是2005年首次于呼吸道样本中检出的新的病原体。人博卡病毒可感染不同年龄段的人群,主要易感人群为儿童,尤以6~24个月的婴幼儿多见。不同地区的流行季节因气候和地理位置的差异有所不同,好发于秋冬季。人博卡病毒1型与呼吸系统疾病密切相关,也可能导致威胁生命的重症,且症状的严重程度与病毒载量呈正相关。人博卡病毒1型常与其他病毒混合感染,可抑制干扰素分泌通路,影响宿主的免疫功能。目前人博卡病毒2~4型的致病性仍不明确,可能与胃肠疾病有关。诊断人博卡病毒急性感染单纯以聚合酶链反应检出DNA为依据并不可靠,应与mRNA、特异性抗原检测等多种方法联合应用,以提高诊断的准确性。目前对于人博卡病毒的认识仍然不足,尚需进一步研究。

关键词：人博卡病毒儿童混合感染致病性

Substitutions of stem-loop subdomains in internal ribosome entry site of Senecavirus A:Impacts on rescue of sequence-modifying viruses

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Journal of Integrative Agriculture 2024年第7期23卷 2391-2406页

作者： Qianqian wang Jie wang Lei Zhang Xiaoxiao Duan lijie Zhu Youming Zhang Yan Li Fuxiao Liu College of Veterinary Medicine Qingdao Agricultural UniversityQingdao 266109China College of Veterinary Medicine Inner Mongolia Agricultural UniversityHuhhot 010018China Shandong New Hope Liuhe Group Co. Ltd.Qingdao 266100China Qingdao Center for Animal Disease Control&Prevention Qingdao 266199China State Key Laboratory of Microbial Technology Shandong UniversityQingdao 266237China

Senecavirus A(SVA)has a positive-sense,single-stranded RNA genome.Its 5´untranslated region harbors an internal ribosome entry site(IRES),comprising 10 larger or smaller stem-loop structures(including a pseudoknot)that have been demonstrated to be well conserved.However,it is still unclear whether each stem-loop subdomain,such as a single stem or loop,is also highly conserved.To clarify this issue in the present study,a set of 29 SVA cDNA clones were constructed by site-directed mutagenesis(SDM)on the IRES.The SDM-modified scenarios included:(1)stem-formed complementary sequences exchanging with each other;(2)loop transversion;(3)loop transition;and(4)point mutations.All cDNA clones were separately transfected into cells for rescuing viable viruses,whereas only four SVAs of interest could be recovered,and were genetically stable during 20 passages.One progeny grew significantly slower than the other three did.The dual-luciferase reporter assay showed that none of the SDM-modified IRESes significantly inhibited the IRES activity.Our previous study indicated that a single motif from any of the ten stem structures,if completely mutated,would cause the failure of virus recovery.Interestingly,our present study revealed three stem structures,whose individual complementary sequences could exchange with each other to rescue sequence-modifying SVAs.Moreover,one apical loop was demonstrated to have the ability to tolerate its own full-length transition,also having no impact on the recovery of sequence-modifying SVA.The present study suggested that not every stem-loop structure was strictly conserved in its conformation,while the full-length IRES itself was well conserved.This provides a new research direction on interaction between the IRES and many factors.

关键词： SVA HCV IRES HCV-like IRES stem-loop structure cDNA clone virus rescue mutation

Synergism of solar-driven interfacial evaporation and photo-Fenton Cr(Ⅵ) reduction by sustainable Bi-MOF-based evaporator from waste polyester

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Journal of Energy Chemistry 2024年第7期94卷 527-540页

作者： Zifen Fan Jie Liu Huajian Liu lijie Liu Yan She Xueying Wen Huiyue wang Guixin Hu Ran Niu Jiang Gong Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSemiconductor Chemistry CenterSchool of Chemistry and Chemical EngineeringHuazhong University of Science andTechnologyWuhan430074HubeiChina

The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is fuzzy.Herein,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater production.Firstly,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic property.Attributing to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of irradiation.When integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced catalysts.In the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.

关键词： Interfacial solar steam generation Cr(VI)reduction Photo-Fenton reaction Metal-organic framework Waste plastic upcycling

Electron-distribution control via Pt/NC and MoC/NC dual junction:Boosted hydrogen electro-oxidation and theoretical study

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Journal of Energy Chemistry 2024年第1期88卷 513-520,I0011页

作者： Feng Zhou Xiaofeng Ke Yihuang Chen Mei Zhao Yun Yang Youqing Dong Chao Zou Xi’an Chen Huile Jin lijie Zhang Shun wang Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000ZhejiangChina Zhejiang Engineering Research Center for Electrochemical Energy Materials and Devices Institute of New Materials&Industry TechnologyWenzhou UniversityWenzhou 325000ZhejiangChina

The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO.

关键词： Hydrogen oxidation reaction Dual junctions CO-tolerance Platinum

联合容积絮凝法去除污水中磷的最佳投药量研究

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绿色科技 2024年第2期26卷 141-146,173页

作者：董晓南国英白雪洁郝燕飞李雯琴王立杰任淑萍张海平河北建筑工程学院河北张家口075000 河北省地质矿产勘查开发局第六地质大队河北石家庄050000 张家口市政水务有限责任公司河北张家口075000

实验研究了在不同磷浓度下铁盐、聚丙烯酰胺(PAM)和钢渣三者联合处理水中磷的方法。探索了在不同磷浓度下铁盐、聚丙烯酰胺(PAM)和钢渣三者联合容积絮凝处理水中磷的最佳投药量。在综合考虑各种情况下,原水磷浓度为8 mg/L时,三者联合容... 详细信息

实验研究了在不同磷浓度下铁盐、聚丙烯酰胺(PAM)和钢渣三者联合处理水中磷的方法。探索了在不同磷浓度下铁盐、聚丙烯酰胺(PAM)和钢渣三者联合容积絮凝处理水中磷的最佳投药量。在综合考虑各种情况下,原水磷浓度为8 mg/L时,三者联合容积絮凝最佳投加量为n(Fe)∶n(P)=2.5,PAM投加量为0.1 mg/L,钢渣投加量为4 g/L;原水磷浓度为4 mg/L时,三者联合容积絮凝最佳投加量为n(Fe)∶n(P)=3.5,PAM投加量为0.05 mg/L,钢渣投加量为3 g/L;原水磷浓度为2 mg/L时,三者联合容积絮凝最佳投加量为n(Fe)∶n(P)=2.5,PAM投加量为0.1 mg/L,钢渣投加量为3 g/L。最佳投药量下的出水磷浓度均满足《地表水环境质量标准》(GB3838-2002)Ⅲ标准。

关键词：铁盐 PAM 钢渣容积絮凝最佳投药量

Direct electron transfer of hemoglobin at 3D graphene–nitrogen doped carbon nanotubes network modified electrode and electrocatalysis toward nitromethane

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Direct electron transfer of hemoglobin at 3D graphene–nitro...