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Simultaneous integration of Fe clusters and NiFe dual single atoms in nitrogen-doped carbon for oxygen reduction reaction

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Nano Research 2024年第4期17卷 2291-2297页

作者： Jirong Bai Yuebin Lian Yaoyao deng Mei Xiang Peng Xu Quanfa Zhou yawen Tang Yaqiong Su Research Center of Secondary Resources and Environment School of Chemical Engineering and MaterialsChangzhou Institute of TechnologyChangzhou 213022China Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Chemistry Engineering Research Center of Energy Storage Materials and Devices of Ministry of EducationNational Innovation Platform(Center)for Industry-Education Integration of Energy Storage TechnologyXi’an Jiaotong UniversityXi’an 710049China

Atomically-dispersed iron-based electrocatalysts are promising substitutes for noble metal electrocatalysts because of excellent performance in oxygen reduction reaction(ORR).Rationally modulating the local coordination environment of the Fe site and optimizing the binding energy of oxygen reduction intermediates are effective strategies to optimize ORR ***,we report a new method in which Ni is introduced to construct NiFe dual single atoms and iron nanoclusters loaded on the nitrogen-doped carbon with a highly porous *** design plays a synergistic role of dual single atoms and clusters,optimizes the 3d orbital and Fermi level of Fe,breaks the symmetrical structure of Fe-N_(4),and effectively improves the adsorption/desorption behavior of the oxygen-containing *** tests show FeNCs/NiFeSAs-NC has an excellent intrinsic *** calculations show the oxygen-containing species on the Ni active site will move to the middle of NiFe(bridge site connection)after optimization and that the key step is OH desorption,with a reaction energy of 0.27 *** electron exchange between NiFe-N6 and Fe-cluster is very strong,further indicating the introduction of Ni species and Fe clusters has a regulatory effect on the electronic structure of Fe-N_(4).

关键词： NiFe dual single atoms Fe clusters OH*adsorption energy oxygen reduction reaction

Magnetically Separable Straw@Fe_(3)O_(4)/Cu_(2)O Composites for Photocatalytic Degradation of Methyl Orange under Visible Light Irradiation

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1003-1009页

作者： Wang Jingjing Zhang yawen School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China

Fe_(3)O_(4)and Cu_(2)O were successively immobilized on alkali-treated straw,and the magnetically separable straw@Fe_(3)O_(4)/Cu_(2)O composite was *** straw@Fe_(3)O_(4)/Cu_(2)O was characterized by Fourier transform infrared spectroscopy,X-ray diffraction,scanning electron microscopy,X-ray photoelectron spectroscopy and vibrating sample magnetometry,*** performance of the straw@Fe_(3)O_(4)/Cu_(2)O was evaluated by measuring the degradation of methyl orange(MO)under irradiation of visible *** introduction of Fe3O4 not only endowed the straw@Fe_(3)O_(4)/Cu_(2)O with magnetic separation feature but also significantly enhanced photocatalytic activity because Fe3O4 could prevent recombination of hole-electron *** active species capture experiment showed that holes(h+),hydroxyl(∙OH)and superoxide(∙O2ˉ)radicals all took part in the MO *** addition,the photocatalytic mechanism of straw@Fe_(3)O_(4)/Cu_(2)O was proposed based on the experimental *** five cycles for the photodegradation of MO,the straw@Fe_(3)O_(4)/Cu_(2)O still displayed good photocatalytic activity,suggesting that the as-prepared composite had great potential for practical use in wastewater treatment.

关键词： Straw Cu_(2)O Fe_(3)O_(4) Photocatalysis Visible light

Cotton flooding and drought analysis regarding growth stages in Hubei,China,using a daily agrometeorological index

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 173-183页

作者： Long Qian Cheng Chen Xiaohong Chen Wenzhi Zeng yawen Gao Kenan deng School of Civil Engineering Sun Yat-sen UniversityGuangzhou 510275China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminatsy Shanghai 200233China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

Cotton yield is restricted worldwide by flooding and drought that occur across various growth *** this study,cotton flooding and drought in Hubei(a major cotton-production province in China)from 1961 to 2019 were analyzed regarding growth stages through a daily index named the standardized antecedent precipitation evapotranspiration index(SAPEI).In addition,the impacts of flooding and drought on cotton climatic yield were quantified using multiple regression *** results showed that the temporal trends of cotton flooding and drought intensities were generally smooth,except for an obvious downward trend for cotton drought intensity at the flowering and boll-forming ***,cotton drought intensity varied more drastically than that of flooding over the ***-flooding proneness was much greater than cotton-drought proneness at all growth stages,and the most flooding-prone and drought-prone periods were identified as the flowering and boll-forming stage and the budding stage,*** terms of spatial distribution,northeastern Hubei and southwestern Hubei were most prone to flooding and drought,*** SAPEI-based regression model(R2=0.490,p<0.001),obviously outperforming the SPEI-based model(R2=0.278,p<0.05),revealed that both cotton flooding and drought exhibited negatively significant effects on cotton climatic yield and that the yield-reducing effect of cotton flooding was much greater than that of ***,when growth stages were further considered using regression analysis,only the flowering and boll-forming stage was detected with a significant yield-reducing effect of cotton *** conclusion,the SAPEI can effectively assist in monitoring cotton flooding and drought;cotton flooding,especially during the flowering and boll-forming stage and that occurring in northeastern Hubei,is the key issue for cotton field water management in Hubei.

关键词： irrigation drainage climatic yield waterlogging

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秦岭中部自然保护区植被生长状况遥感监测

自然保护地 2022年第2期2卷 48-59页

作者：王晓雅凌子燕陈研翟俊邓雅文荔琢彭凯锋遥感科学国家重点实验室北京师范大学地理科学学部北京100875 北京师范大学地理科学学部北京100875 环境遥感与数字城市北京市重点实验室北京师范大学地理科学学部北京100875 北部湾环境演变与资源利用教育部重点实验室南宁师范大学地理科学与规划学院南宁530001 南宁师范大学地理科学与规划学院南宁530001 生态环境部卫星环境应用中心北京100094

秦岭地区是中国自然保护区较为集中的地区之一,也是中国重要的生态保护屏障,秦岭中部有多个国家级自然保护区,然而目前鲜有研究分析秦岭中部自然保护区的植被生长状况,且对于自然保护区的保护成效尚不明确,因此探究该区域长时序的植被... 详细信息

秦岭地区是中国自然保护区较为集中的地区之一,也是中国重要的生态保护屏障,秦岭中部有多个国家级自然保护区,然而目前鲜有研究分析秦岭中部自然保护区的植被生长状况,且对于自然保护区的保护成效尚不明确,因此探究该区域长时序的植被生长状况有助于了解秦岭地区自然保护区的保护成效及植被生长情况。本文利用Landsat、MODIS、GLASS等遥感数据及相关产品分析了秦岭中部地区14个国家级自然保护区近二三十年归一化植被指数(NDVI)、叶面积指数(LAI)、净初级生产力(NPP)、植被覆盖度(FVC)的空间分布特征及趋势变化情况,并综合4个指标探究秦岭中部自然保护区的植被变化情况与保护成效,研究结果表明,1)在空间上,太白山自然保护区中南部与汉中朱鹮自然保护区南部的植被类型与其他区域存在差异;2)在趋势上,各自然保护区的植被生长状况呈现显著增加趋势或维持稳定状态;3)综合各指标发现,秦岭中部自然保护区的整体保护成效良好,但极个别地区仍需要重点关注。

关键词：秦岭中部自然保护区植被指数生长状况动态趋势遥感

An effective pharmacological hydrogel induces optic nerve repair and improves visual function

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Science China(Life Sciences) 2024年第3期67卷 529-542页

作者： Lipeng Wang Shan Zhang yawen Han Shuo Tang Jiarui Li Lina Bu Dongyu Zhao Hongkui deng Department of Cell Biology Schoolof Basic Medical SciencesPeking University Stem Cell Research CenterStateKey Laboratoryof Naturaland Biomimetic DrugsPeking University Health Science Center Beijing 100191China MOE Key Laboratory of Cell Proliferation and Differentiation College of Life SciencesPeking-Tsinghua Center for Life SciencesPeking UniversityBeijing 100871China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China Changping Laboratory Beijing 102206China Department of Ophthalmology Peking University People's Hospital Eye Diseases and Optometry InstituteBeijing 100871China Department of Biomedical Informatics School of Basic Medical SciencesPeking UniversityBeijing 100191China

Irreversible eye lesions, such as glaucoma and traumatic optic neuropathy, can cause blindness;however, no effective treatments exist. The optic nerve, in particular, lacks the capacity to spontaneously regenerate, requiring the development of an effective approach for optic nerve repair, which has proven challenging. Here, we demonstrate that a combination of the small molecules 3BDO and trichostatin A(TSA)—which regulate mTOR and HDAC, respectively—packaged in thermosensitive hydrogel for 4-week-sustained release after intravitreal injection, effectively induced optic nerve regeneration in a mouse model of optic nerve crush injury. Moreover, this combination of 3BDO and TSA also protected axon projections and improved visual responses in an old mouse model(11 months old) of glaucoma. Taken together, our data provide a new, local small molecule-based treatment for the effective induction of optic nerve repair, which may represent a foundation for the development of pharmacological methods to treat irreversible eye diseases.

关键词： retinal ganglion cell axon regeneration old-age glaucoma small molecules pharmacological hydrogel visual function repair

Advances and prospects of rare earth metal-organic frameworks in catalytic applications

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Journal of Rare Earths 2020年第8期38卷 801-818,I0001页

作者： Xiaochen Sun Kun Yuan yawen Zhang Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

In recent years,rare earth metal-organic frameworks(RE-MOFs)have attracted increasing attention because of abundant coordination behaviors,adjustable channels and stable *** various electron structures of rare earth ions contribute to the catalytic applications of RE-MOFs and their *** this review,we systematically summarize the research progress that using RE-MOFs and their derivates as catalysts for organic reaction,photocatalytic reaction,and CO oxidation *** major parts include synthetic strategies and catalytic applications of the ***,impressive achievements of RE-MOF catalysts are emerging and a prospect is provided for the development of RE-MOF catalysts at the end of the review.

关键词： Rare earth metal-organic frameworks Synthesis methodology Heterogeneous catalysis Photocatalysis

Non-invasive Observation of Human Tissue Samples with Full Field Optical Coherence Tomography

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Chinese Journal of Electronics 2019年第5期28卷 987-992页

作者： MU Ning GAO Wanrong ZHOU yawen Department of Optical Engineering Nanjing University of Science and Technology

In this work, we report on non-invasive observation of human esophagus, liver, and uterus samples with Full field optical coherence tomography(FFOCT).ln imaging process, fresh human samples were fixed in formalin immediately after excision and then imaged directly without staining and cutting the samples into a serial of thin slices. Tissue microstructures of each type of normal or cancerous tissue as well as their changes with the increase of the depth beneath tissue surface can be identified in the depth-resolved images. The results demonstrate the potential of applications of the en face images in clinic practice.

关键词： En face images Optical sectioning imaging Full field optical coherence tomography(FFOCT) Tissue microstructures

Effects of solvents and temperature on spherulites of self-assembled phloroglucinol tristearate

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Frontiers of Chemical Science and Engineering 2020年第3期14卷 389-396页

作者： yawen Yao Sabine Rosenfeldt Kai Zhang Wood Technology and Wood Chemistry Georg-August-University of Goettingen37077 GottingenGermany Department of Chemistry and Bavarian Polymer Institute University of Bayreuth95447 BayreuthGermany

Herein,phloroglucinol tristearate(PhgTS)was used to study the crystallization process due to its unique symmetric structure containing a benzene ring and three aliphatic *** of crystallized PhgTS from four solvents under diverse conditions were analyzed in detail and their formation process was *** cross is shown by PhgTS spherulites obtained from aprotic solvents via polarized optical *** comparison,no Maltese cross can be observed from branch-like crystals formed from protic *** on the micro-scaled morphology,lamellae were found to be the basic blocks constructing both PhgTS spherulites and branch-like crystals,which were formed predominantly by stacked PhgTS *** differential characters of the solvents did not affect the formation of lamellas,the solvents played a crucial role in the formation of self-assembled microscaled *** particular,the morphologies of spherulites were strongly affected by the concentration of PhgTS solutions,surrounding tempera-ture and evaporation rate of ***,a higher concentration of PhgTS led to more homogeneous spherulites,a lower evaporation rate resulted in more compact spherulites,and a higher surounding temperature generated preferentially more ring-banded spherulites of PhgTS.

关键词： phloroglucinol tristearate aprotic and protic solvent self-assembly spherulites

Compensation for Neurodegeneration by Hippocampal Neurogenesis in Alzheimer’s Disease: Where is the way?

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Neuroscience Bulletin 2021年第6期37卷 885-888页

作者： Jie Zheng yawen Li Department of Pharmacology Key Laboratory of Basic Pharmacology of Ministry of EducationJoint International Research Laboratory of Ethnomedicine of Ministry of EducationKey Laboratory of Basic Pharmacology of Guizhou ProvinceZunyi Medical UniversityZunyi 563000China Digestive Disease Institute of Guizhou Province Clinical Medical Research Center of Digestive Diseases of Guizhou ProvinceDepartment of GastroenterologyAffiliated Hospital of Zunyi Medical UniversityZunyi 563000China

Neurodegeneration,a defining hallmark of Alzheimer's disease(AD),features the progressive loss of neuronal structure and *** approaches to AD show limited efficiency in halting the neurodegeneration to *** the lack of neuronal renewability in most subareas of the adult brain,symptomatic drugs or treatments cannot repopulate neurons and rewire the degenerated neuronal circuits in AD.

关键词： degeneration Alzheimer drugs