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OH regulator of highly dispersed Ru sites on host Pd nanocrystals for selective ethanol electro-oxidation

Nano Research 2024年第5期17卷 3863-3871页

作者： Zhihe Xiao Yueguang Chen Renjie Wu Yuwei he chunfeng Shi Leyu Wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Research Institute of Petroleum Processing SINOPECBeijing 100083China

The ethanol oxidation reaction(EOR)is crucial in direct alcohol fuel cells and chemical production.However,the electro-oxidation of ethanol molecules to produce acetaldehyde and carbon monoxide can poison the active sites of nanocatalysts,resulting in reduced performance and posing challenges in achieving high activity and selectivity for ethanol oxidation.In this study,we employed a dynamic seed-mediated method to precisely modify highly dispersed Ru sites onto well-defined Pd nanocrystals.The oxyphilic Ru sites serve as"OH valves",regulating water dissociation,while the surrounding Pd atomic arrangements control electronic states for the oxidation dehydrogenation of carbonaceous intermediates.Specifically,Ru0.040@Pd nanocubes(Ru:Pd=0.04 at.%),featuring(100)facets in Ru-Pd4 configurations,demonstrate an outstanding mass activity of 6.53 A·mgPd^(-1) in EOR under alkaline conditions,which is 6.05 times higher than that of the commercial Pd/C catalyst(1.08 A·mgPd-1).Through in-situ experiments and theoretical investigations,we elucidate that the hydrophilic Ru atoms significantly promote the dynamic evolution of H_(2)O dissociation into OHads species,while the electron redistribution from Ru to adjacent Pd concurrently adjusts the selective oxidation of C_(2) intermediates.This host-guest interaction accelerates the subsequent oxidation of carbonaceous intermediates(CH_(3)CO_(ads))to acetate,while preventing the formation of toxic*CHx and*CO species,which constitutes the rate-determining step.

关键词： OH regulator atomic sites ethanol electro-oxidation host-guest interaction

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A cost-efficient quantum access network with qubit-based synchronization

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 12-22页

作者： chunfeng Huang Ye Chen Tingting Luo Wenjie he Xin Liu Zhenrong Zhang Kejin Wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Multimedia Communications and Network Technology School of Computer Electronics and InformationGuangxi UniversityNanning 530004China

Quantum key distribution(QKD)is a physical layer encryption technique that enables two distant parties to exchange secure keys with information-theoretic security.In the last two decades,QKD has transitioned from laboratory research to real-world applications,including multi-user quantum access networks(QANs).This network structure allows users to share a single-photon detector at a network node through time-division multiplexing,thereby significantly reducing the network cost.However,current QAN implementations require additional hardware for auxiliary tasks such as time synchronization.To address this issue,we propose a cost-efficient QAN that uses qubit-based synchronization.In this approach,the transmitted qubits facilitate time synchronization,eliminating the need for additional synchronization hardware.We tested our scheme by implementing a network for two users and successfully achieved average secure key rates of 53.84 kbps and 71.90 kbps for each user over a 50-km commercial fiber spool.In addition,we investigated the capacity of the access network under cross-talk and loss conditions.The simulation results demonstrate that this scheme can support a QAN with 64 users with key rates up to 1070 bps.Our work provides a feasible and cost-effective way to implement a multi-user QKD network,further promoting the widespread application of QKD.

关键词： quantum key distribution quantum access network qubit-based synchronization

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Ligand effect in surface atomic sites of group VI B transition metals on ultrathin Pt nanowires for enhanced oxygen reduction

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Nano Research 2024年第6期17卷 5298-5304页

作者： Yuwei he Yueguang Chen Renjie Wu Zhihe Xiao Mengxian Li chunfeng Shi Leyu Wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Petroleum Molecular and Process Engineering SINOPEC Research Institute of Petroleum Processing Co.Beijing 100083China

Increasing the utilization efficiency of platinum is critical for advancing proton exchange-membrane fuel cells(PEMFCs).Despite extensive research on catalysts for the cathodic oxygen reduction reaction(ORR),developing highly active and durable Pt-based catalysts that can suppress surface dealloying in corrosive acid conditions remains challenging.herein,we report a facile synthesis of bimetallic ultrathin PtM(M=Mo,W,and Cr)nanowires(NWs)composed of group VI B transition metal atomic sites anchored on the surface.These NWs possess uniform sizes and well-controlled atomic arrangements.Compared to PtW and PtCr catalysts,the PtMo0.05 NWs exhibit the highest half-wave potential of 0.935 V and a mass activity of 1.43 A·mgPt^(−1).Remarkably,they demonstrate a remarkable 23.8-fold enhancement in mass activity compared to commercial Pt/C for ORR,surpassing previously reported Pt-based catalysts.Additionally,the PtMo NWs cathode in membrane electrode assembly tests achieves a remarkable peak power density of 1.443 W·cm^(−2)(H_(2)-O_(2)conditions at 80℃),which is 1.09 times that of commercial Pt/C.The ligand effect in the bimetallic surface not only facilitates strong coupling between Mo(4d)and Pt(5d)atomic orbitals to hinder atom leaching but also modulates the d-states of active site,significantly optimizing the adsorption of key oxygen(*O and*OH)species and accelerating the rate-determining step in ORR pathways.

关键词： ligand effect oxygen reduction reaction group VI B transition metal ultrathin nanowires multiple oxygen species

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Accumulation, transportation, and distribution of tetracycline and cadmium in rice

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Journal of Environmental Sciences 2023年第4期126卷 58-69页

作者： chunfeng he Jini Zhou Chen Yang Zhiyi Song Junheng he Ziqing Huang Yurong Deng Jinling Wang Yu Xiong Zhi Dang College of Environment and Energy South China University of TechnologyGuangzhou 510006China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationGuangzhou 510006China Department of Environmental Sciences The State University of New JerseyRutgers UniversityNew BrunswickNJ 08901USA Guangdong Institute of Ecological Environment and Soil Guangzhou 510650China

Co-exposure to heavy metal and antibiotic pollution might result in complexation and synergistic interactions,affecting rice growth and further exacerbating pollutant enrichment.Therefore,our study sought to clarify the influence of different Tetracycline (TC) and Cadmium(Cd) concentration ratios (both alone and combined) on rice growth,pollutant accumulation,and transportation during the tillering stage in hydroponic system.Surprisingly,our findings indicated that the interaction between TC and Cd could alleviate the toxic effects of TC/Cd on aerial rice structures and decrease pollutant burdens during root elongation.In contrast,TC and Cd synergistically promoted the accumulation of TC/Cd in rice roots.However,their interaction increased the accumulation of TC in roots while decreasing the accumulation of Cd when the toxicant doses increased.The strong affinity of rice to Cd promoted its upward transport from the roots,whereas the toxic effects of TC reduced TC transport.Therefore,the combined toxicity of the two pollutants inhibited their upward transport.Additionally,a low concentration of TC promoted the accumulation of Cd in rice mainly in the root tip.Furthermore,a certain dose of TC promoted the upward migration of Cd from the root tip.Laser ablation-inductively coupled plasma mass spectrometry demonstrated that Cd mainly accumulated in the epidermis and stele of the root,whereas Fe mainly accumulated in the epidermis,which inhibited the absorption and accumulation of Cd by the rice roots through the generation of a Fe plaque.Our findings thus provide insights into the effects of TC and Cd co-exposure on rice growth.

关键词： Laser ablation-inductively coupled plasma mass spectrometry Tetracycline Cadmium Accumulation Distribution

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Alterations of soil aggregates and intra-aggregate organic carbon fractions after soil conversion from paddy soils to upland soils:Distribution,mineralization and driving mechanism

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Pedosphere 2024年第1期34卷 121-135页

作者： Longfei KANG Jiamei WU chunfeng ZHANG Baoguo ZHU Guixin CHU College of Life Science Shaoxing UniversityShaoxing 312000China The Key Laboratory of Oasis Eco-agriculture Xinjiang Production and Construction Group/Department of Resources and Environmental SciencesAgronomy CollegeShihezi UniversityShihezi 832000China Hunan Institute of Agricultural Environment and Ecology Changsha 410000China Jiamusi Branch Heilongjiang Academy of Agricultural SciencesJiamusi 154007China

Investigating the impacts of soil conversion on soil organic carbon(OC) content and its fractions within soil aggregates is essential for defining better strategies to improve soil structure and OC sequestration in terrestrial ecosystems. However, the consequences of soil conversion from paddy soil to upland soil for soil aggregates and intra-aggregate OC pools are poorly understood. Therefore, the objective of this study was to quantify the effects of soil conversion on soil aggregate and intra-aggregate OC pool distributions. Four typical rice-producing areas were chosen in North and South China, paired soil samples(upland soil converted from paddy soil more than ten years ago vs. adjacent paddy soil) were collected(0–20 cm) with three replicates in each area. A set of core parameters(OC preservation capacity, aggregate carbon(C) turnover, and biological activity index) were evaluated to assess the responses of intra-aggregate OC turnover to soil conversion. Results showed that soil conversion from paddy soil to upland soil significantly improved the formation of macro-aggregates and increased aggregate stability. It also notably decreased soil intra-aggregate OC pools, including easily oxidized OCa(EOCa), particulate OCa(POCa), and mineral-bound(MOCa) OC, and the sensitivity of aggregate-associated OC pools to soil conversion followed the order: EOCa(average reduction of 21.1%) > MOCa(average reduction of 15.4%) > POCa(average reduction of 14.8%). The potentially mineralizable C(C_(0)) was significantly higher in upland soil than in paddy soil, but the corresponding decay constant(k) was lower in upland soil than in paddy soil. Random forest model and partial correlation analysis showed that EOCa and pH were the important nutrient and physicochemical factors impacting k of C mineralization in paddy soil,while MOCa and C-related enzyme(β-D-cellobiohydrolase) were identified as the key factors in upland soil. In conclusion, this study evidenced that soil conversion from paddy soil to upland soil increased the pe

关键词： decay constant easily oxidized organic C macro-aggregate meso-aggregate micro-aggregate mineral-bound organic C particulate organic C potentially mineralizable C

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Increased N6-methyladenosine is related to the promotion of the methyltransferase METTL14 in ovarian aging

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Genes & Diseases 2024年第3期11卷 151-154页

作者： chunfeng Qian Zhenxing Liu Yonghong Qian Jie Ding Rulei Chen Han Su Minghong Shen Hong Li Boxian Huang State Key Laboratory of Reproductive Medicine and Offspring health Suzhou Affliated Hospital of Nanjing Medicine and Offspring HealthSuzhou Affiliated Hospital of Nanjing Medical UniversitySuzhouMunicipal HospitalGusu SchoolNanjing Medical UniversitySuzhouJiangsu 215002China Department of Gynecology Affliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu School of Nanjing Medical UniversitySuzhouJiangsu 215002China Department of Pathology Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu School of Nanjing Medical UniversitySuzhouJiangsu 215002China

The ovary is a vital female reproductive organ that functions to produce oocyte gametes and cyclically expressed sex hormones to maintain reproductive capacity and hormone homeostasis.Ovarian aging,characterized by declines in follicle quantity and oocyte quality,leads to premature ovarian failure,premature ovarian insufficiency,or diminished ovarian reserve,thus contributing to female infertility.Distinct gene-expression signatures from RNA transcriptional level and post-transcriptional regulation are relative to oocyte quality and reproductive age.

关键词： promotion signature maintain

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Synthesis and characterization of high entropy(TiVNbTaM)_(2)AlC(M=Zr,Hf)ceramics

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Journal of Advanced Ceramics 2024年第2期13卷 237-246页

作者： Lei Cao Qiqiang Zhang Lijing Du Shuai Fu Detian Wan Yiwang Bao Qingguo Feng chunfeng Hu Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Green Building Materials China Building Materials AcademyBeijing 100024China

The high-entropy design of MAX phases is expected to confer superior properties,but its study was hindered by the complex synthesis method and limited purity of samples.In this work,two noteworthy types of high-entropy MAX phase structural ceramics,high-entropy(TiVNbTaM)_(2)AlC(M=Zr,Hf),were designed and prepared by the in-situ synthesis using spark plasma sintering(SPS).The microstructure and lattice parameters of sintered samples were determined.Compared with the single-component MAX phases,the highly pure high-entropy(TiVNbTaZr)_(2)AlC sample had good physical and mechanical properties,including electrical conductivity of 0.96×106Ω^(-1)·m^(-1),thermal expansion coefficient of 3.65×10^(-6) K^(-1),thermal conductivity of 8.98 W·m^(-1)·K^(-1),Vickers hardness of 9.80 GPa,flexural strength of 507 MPa,fracture toughness of 5.62 MPa·m^(1/2),and compressive strength of 1364 MPa,which exhibited the remarkable hardening-strengthening effect.

关键词： MAX phase high-entropy ceramic microstructure physical properties mechanical properties

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异形纤维及其制造技术进展

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高分子材料科学与工程 2024年第3期40卷 172-179页

作者：范春峰何鉴峰王建北京化工大学机电工程学院北京100029

异形纤维是指横截面形状为非圆形的纤维,可弥补圆形纤维在抗扭强度、粗糙度、弹性、表观等性能方面的不足,并具有良好的光泽、染色、抗污、阻燃、隔热、隔音等性能,在纺织、复合材料、建筑、生物医学、汽车、航空航天、光学等领域得到... 详细信息

异形纤维是指横截面形状为非圆形的纤维,可弥补圆形纤维在抗扭强度、粗糙度、弹性、表观等性能方面的不足,并具有良好的光泽、染色、抗污、阻燃、隔热、隔音等性能,在纺织、复合材料、建筑、生物医学、汽车、航空航天、光学等领域得到了广泛应用。文中介绍了异形纤维的类型、特点、应用领域,总结了异形纤维的制造技术及其影响因素,分析了异形纤维横截面形态表征方法及对性能的影响。相关综述可为异形纤维的研究开发提供科学参考和技术借鉴。

关键词：异形纤维制造方法力学性能复合材料

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New dual functional CYP450 gene involves in isoflavone biosynthesis in Glycine max L.

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Synthetic and Systems Biotechnology 2023年第1期8卷 157-167页

作者： Yaying Xia chunfeng he Su Yan Jinyue Liu Haijun Huang Xue Li Qian Su Wenbo Jiang Yongzhen Pang Key Laboratory of Plant Resources and Beijing Botanical Garden Institute of BotanyChinese Academy of SciencesBeijing100093China Institute of Animal Science Chinese Academy of Agricultural SciencesBeijing100193China University of Chinese Academy of Sciences Beijing100049China

Glycine max L.accumulates a large amount of isoflavonoid compounds,which is beneficial for plant defense,plant-microbe symbiotic interactions,and human health.Several CYP450 subfamily genes are involved in the flavonoid biosynthetic pathway in plants.In the present study,we found 24 CYP82 subfamily genes were differentially expressed in various tissues of soybean,in Phytophthora sojae-infected soybean varieties and in soybean hairy roots treated with cell wall glucan elicitor.Six of them(GmCYP82A2,GmCYP82A3,GmCYP82A4,GmCYP82A23,GmCYP82C20 and GmCYP82D26)were co-expressed with other known isoflavonoid pathway genes in soybean.Their enzymatic activity in yeast feeding assays showed that only GmCYP82D26 was able to convert naringenin to daidzein with both aryl migration and dehydration function.When GmCYP82D26 was over-expressed in soybean hairy roots,the contents of the two major isoflavonoid aglycones in soybean(daidzein and genistein)were reduced,but total flavonoids were not affected.When GmCYP82D26 was suppressed by RNAi in the hairy roots,daidzein content was decreased but genistein content was increased,with unchanged total flavonoid content.GmCYP82D26 was found to be localized in the endoplasmic reticulum at subcellular level when transiently expressed in tobacco leaf epidermis.GmCYP82D26 gene was preferentially expressed in roots,with low expression level in other tissues in soybean.Homology modeling and molecular docking showed that GmCYP82D26 could form hydrogen bond with both heM and naringenin at C5-OH and C4 carbonyl.All these results indicated that GmCYP82D26 possesses new and dual enzymatic activity,which bridges the two branches(daidzein and genistein branch)of isoflavonoid pathway in soybean.

关键词： Soybean CYP82 CYP82D26 Isoflavonoids Enzymatic activity

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A 1-bp deletion in the MC04g1399 is highly associated with failure to produce fruit wart in bitter gourd

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Horticultural Plant Journal 2024年第1期10卷 171-180页

作者： Jia Liu Junjie Cui Jichi Dong Jian Zhong chunfeng Zhong Fanchong Yuan Wendong Guan Fang Hu Jiaowen Cheng Kailin Hu College of Horticulture South China Agricultural UniversityGuangzhouGuangdong 510642China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China) Ministry of Agriculture and Rural AffairsGuangzhouGuangdong 510642China Guangdong Vegetables Engineering Research Center GuangzhouGuangdong 510642China Department of Horticulture Foshan UniversityFoshanGuangdong 528225China henry Fok School of Biology and Agricultural Shaoguan UniversityShaoguanGuangdong 512023China

Fruit wart is an important appearance trait influencing consumer preferences of bitter gourd(Momordica charantia L.).The molecular genetic mechanisms underlying fruit wart formation in bitter gourd are largely unknown.In this study,genetic analysis based on four generations showed that fruit wart formation in bitter gourd was controlled by a single dominant locus named as Fwa.The Fwa locus was initially mapped into a 4.82 Mb region on pseudochromosome 4 by BSA-seq analysis and subsequently narrowed down to a 286.30 kb region by linkage analysis.A large F2population consisting of 2360 individuals was used to screen recombinants,and the Fwa locus was finally fine mapped into a 22.70 kb region harboring four protein-coding genes through recombination analysis.MC04g1399,encoding an epidermal patterning factor 2-like protein,was proposed as the best candidate gene for Fwa via sequence variation and expression analysis.In addition,a 1-bp insertion and deletion(InDel)variation within MC04g1399 was converted to a cleaved amplified polymorphic sequence(CAPS)marker that could precisely distinguish between the warty and non-warty types with an accuracy rate of 100%among a wide panel of 126 bitter gourd germplasm resources.Our results not only provide a scientific basis for deciphering the molecular mechanisms underlying fruit wart formation but also provide a powerful tool for efficient genetic improvement of fruit wart via marker-assisted selection.

关键词： Bitter gourd Fruit wart Bulk segregant analysis Fine-mapping Candidate gene

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