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Pr-Tb synergistic strengthening on coercivity of Nd-Ce-Fe-B magnets grain boundary diffused with Pr-Tb-Al-Ga alloys

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Journal of Rare Earths 2024年第9期42卷 1704-1709页

作者： Ruifang Song hang zhao Haibo Feng Institute of Functional Materials Central Iron & Steel Research Institute

Sintered Nd-Ce-Fe-B magnets were grain boundary diffused（GBDed） with PrxTb80-xAl10Ga10（at%）(x=0,20,40,60,80) *** effect of Pr/Tb content in diffusion source on magnetic properties,microstructure and elements distribution of GBDed magnets was *** Pr is used to substitute for 75% Tb in diffusion source,Tb consumption per unit coercivity improvement of GBDed magnet reduces by 77%,compared with the Tb80Al10Ga10diffused *** element diffuses into magnets and then forms Tb-rich shell with high magneto-crystalline anisotropy field surrounding main phase grains,resulting in substantial coercivity *** with low melting point diffuses deeply along liquid grain boundary phase during GBD *** can eliminate some sharp defects of main phase grains and make grain boundaries smooth,which provides diffusion channels for further diffusion of Tb ***,there are more diffusion channels for Tb and less Tb enriched at surface region,making Tb diffuse more deeply and improving Tb utilization *** method significantly improves the coercivity,and realizes the green,efficient and high-quality utilization of heavy rare earth（HRE）elements.

关键词： Grain boundary diffusion Rare earths Microstructure Synergistic strengthening

Heterocatalytic ethylene methoxycarbonylation via a pseudo-hydride pathway over Pt/MoS

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Science China Chemistry 2024年

作者： Bo-hang zhao Bin Zhang Institute of Molecular Plus Department of Chemistry School of Science Tianjin University

Ethylene (C2H4) methoxycarbonylation (EMC) with CO and methanol (CH3OH) to methyl propanoate (MP) is industrially important due to its 100%atom efficiency [1].However, the heavy reliance on homogeneous Pd-based catalysts and strong acid media over commercial EMC processes still causes economic and environmental concerns[2]. At present, supported single-atom catalysts (SACs) can serve as bridges for accessing homogeneous catalysts in traditional heterogeneous catalytic processes. SACs have been extensively studied because they may provide new opportunities for exploring heterogeneous catalysts for the EMC process [3]. However, the mechanism of the heterocatalytic EMC process on SACs is still unclear. Therefore,developing efficient SACs and unveiling their working mechanism are highly important for identifying the heterocatalytic EMC field.

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Nitrite-catalyzed economic and sustainable bromocyclization of tryptamines/tryptophols to access hexahydropyrrolo[2,3-b]indoles/tetrahydrofuroindolines in batch and flow

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Chinese Chemical Letters 2024年第7期35卷 247-252页

作者： Xiao Xiao Biao Chen Jia-Wei Li Jun-Bo Zheng Xu Wang hang zhao Fen-Er Chen Institute of Pharmaceutical Science and Technology Collaborative Innovation Center of Yangtze River Delta Region Green PharmaceuticalsZhejiang University of TechnologyHangzhou 310014China College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China

A highly efficient and concise bromocyclization has been successfully achieved,in which tryptamine/tryptophol derivates can be transformed to valuable HPI/TFI scaffolds with economic and green ***,a controllable cascade transformation of bromocyclization and aromatic bromination has also been smoothly achieved to form dibrominated HPIs and *** could be successfully scaled up under both the batch process and a continuous flow *** most remarkable peculiarity of our process over all previous methods is that the generated water is the major ***,successful application of this new protocol has been demonstrated by the pharmaceutical and natural products syntheses.

关键词： Tryptamines and tryptophols Nitrite Economic and sustainable bromocyclization HPI and TFI structures Bath and flow

Evaluating the necessity of autumn irrigation on salinized soil by considering changes in soil physicochemical properties

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Pedosphere 2024年第4期 837-842页

作者： hang zhao Jingwei WU Changsen LI Yawen LIU Rui Zhang Qiang zhao State Key Laboratory of Water Resources Engineering and Management Wuhan University

Dear Editor,Soil salinization is one of the main forms of global soil degradation,which seriously threatens food security production (Liu et al.,2022).Proper irrigation is the main management measure to control soil salinization (Aragüés et al.,2015;Machado and Serralheiro,2017).For example,in Hetao Irrigation District in Inner Mongolia of northwestern China,the effects of irrigation,seasonal freezing-thawing,and evaporation have led to serious soil salinization *** the 1980s,autumn irrigation (AI) has typically been implemented widely in Hetao Irrigation District before soil freezing (Li et al.,2010;Lu et al.,2019),to leach the salts accumulated on the surface and maintain sufficient soil moisture to create a suitable environment for the next spring sowing.

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“学前教育”解析

教育科学研究 2024年第4期 28-37页

作者：侯怀银赵航山西大学教育科学学院

“学前教育”一词自出现以来，在不同历史时期和不同地域有着不同的界定。目前关于这一概念的认识主要集中在性质、对象及关系三个层面。学前教育是指对出生至接受小学教育前的儿童所实施的、以促进儿童身心各方面健康成长为直接目标的... 详细信息

“学前教育”一词自出现以来，在不同历史时期和不同地域有着不同的界定。目前关于这一概念的认识主要集中在性质、对象及关系三个层面。学前教育是指对出生至接受小学教育前的儿童所实施的、以促进儿童身心各方面健康成长为直接目标的保育和教育活动的总和。学前教育具有教育对象的稚嫩性、教育主体的多样性、教育内容的生活性、教育活动的游戏性、教育影响的奠基性和教育事业的公益性等特征。学前教育与幼儿教育、早期教育、幼儿园教育、儿童教育、家庭教育等相关概念既有联系，又有区别。

关键词：学前教育概念内涵外延特征

Gene expression profiles in early leaf of rice(Oryza sativa)and foxtail millet(Setaria italica)

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The Crop Journal 2024年第3期12卷 776-787页

作者： Jing Sun Chen Deng Xiuru Dai Haoshu Li Liying Zhang Jingke Wang hang zhao Yirong Yang NghiVan Phung Zhiguo Zhang Pinghua Li Xuehui Sun Tiegang Lu Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China College of Agronomy Shandong Agricultural UniversityTai’an 271018ShandongChina Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101ShandongChina

Plant anatomy is patterned early during leaf development which suggests studying the spatial–temporal transcriptomes of primordia will help identify critical regulative and functional *** successfully isolated the leaf primordia tissues from the C3grass rice and the C4grass foxtail millet by laser capture microdissection(LCM)and studied the gene expression throughout leaf developmental *** data analysis uncovered the conserved expression patterns of certain gene clusters both in rice and foxtail millet during leaf *** revealed genes and transcription factors involved in vein formation,stomatal development,and suberin *** identified 79 candidate genes associated with functional regulation of C4anatomy *** phenotype of the candidate genes revealed that knock-out of a putative polar auxin transport related gene NAL1 resulted significantly reduced veinal space in rice *** present work provides a foundation for future analyses of genes with novel functions in grasses and their role in leaf development,in particular the role in leaves with a contrasting C3vs.C4biosynthetic pathway.

关键词： Rice Foxtail millet Leaf development RNA-seq LCM

Study of the spatial growth of stimulated Brillouin scattering in a gas-filled hohlraum via detecting the driven ion acoustic wave

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Matter and Radiation at Extremes 2024年第2期9卷 36-49页

作者： Chaoxin Chen Tao Gong Zhichao Li Liang Hao Yonggang Liu Xiangming Liu hang zhao Yaoyuan Liu Kaiqiang Pan Qi Li Sanwei Li Zhijun Li Sai Jin Feng Wang Dong Yang Laser Fusion Research Center China Academy of Engineering PhysicsMianyangSichuan 621900People’s Republic of China Institute of Applied Physics and Computational Mathematics Beijing 100094People’s Republic of China

In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatialgrowth of stimulated Brillouin scattering (SBS) in a gas-filled hohlraum by detecting the SBS-driven ion acoustic wave. High-quality timeresolved SBS and TS spectra are obtained simultaneously in the experiment, and these are analyzed by a steady-state code based on theray-tracing model. The analysis indicates that ion–ion collisions may play an important role in suppressing SBS growth in the Au plasma;as aresult, the SBS excited in the filled gas region is dominant. In the early phase of the laser pulse, SBS originates primarily from the high-densityplasma at the edges of the interaction beam channel, which is piled up by the heating of the interaction beam. Throughout the duration of thelaser pulse, the presence of the TS probe beam might mitigate SBS by perturbing the density distribution around the region overlapping withthe interaction beam.

关键词： scattering filled Brillouin

传染病防疫中的专家参与和美国卫生防疫治理的专业化

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自然辩证法通讯 2024年第4期46卷 7-14页

作者：赵航南开大学世界近现代史研究中心天津330350

19世纪50年代,美国南部传染病横行,卫生防疫并成为亟待解决的社会问题。为了遏制黄热病流行,路易斯安那州的政府与医生群体展开合作,建立了一个有效的传染病治理模式。1856-1860年,美国医学界召开全国卫生和检疫会议,来完善传染病防疫... 详细信息

19世纪50年代,美国南部传染病横行,卫生防疫并成为亟待解决的社会问题。为了遏制黄热病流行,路易斯安那州的政府与医生群体展开合作,建立了一个有效的传染病治理模式。1856-1860年,美国医学界召开全国卫生和检疫会议,来完善传染病防疫的专业理论,推动了卫生知识的理论沿革。内战时期,医生群体在战争中实践了会议的专业理论,改革了联邦军队的卫生体系,同时推动了医学卫生知识的社会普及。19世纪后半期,医生群体开始广泛进入政府卫生机构,参与卫生治理工作。医生的“专业性”也开始得到社会的广泛承认。至此,美国公共卫生治理的专业化程度显著提高。

关键词：黄热病公共卫生专家参与医学专业化

Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles:Sequential Embryo Transfer or Double-blastocyst Transfer?

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Current Medical Science 2024年第1期44卷 212-222页

作者： Qiao-hang zhao Yu-wei SONG Jian CHEN Xiang ZHOU Ji-lai XIE Qiu-ping YAO Qi-yin DONG Chun FENG Li-ming ZHOU Wei-ping FU Min JIN The Second Affiliated Hospital of Zhejiang University School of Medicine Hangzhou 310052China Jiaxing Maternity and Child Health Care Hospital Jiaxing 314051China Huzhou Maternity and Child Care Hospital Huzhou 313002China Ningbo Women and Children's Hospital Ningbo 315000China

Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of SeET and DBT on pregnancy *** Totally,261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective *** to different embryo quality and transfer strategies,they were divided into four groups:group A,good-quality SeET(GQ-SeET,n=38 cycles);group B,poor-quality or mixed-quality SeET(PQ/MQ-SeET,n=31 cycles);group C,good-quality DBT(GQ-DBT,n=121 cycles);and group D,poor-quality or mixed-quality DBT(PQ/MQ-DBT,n=71 cycles).The main outcome,clinical pregnancy rate,was compared,and the generalized estimating equation(GEE)model was used to correct potential confounders that might impact pregnancy *** GQ-DBT achieved a significantly higher clinical pregnancy rate(aOR 2.588,95%CI 1.267–5.284,P=0.009)and live birth rate(aOR 3.082,95%CI 1.482–6.412,P=0.003)than PQ/***,the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET(aOR 4.047,95%CI 1.218–13.450,P=0.023).The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT,and the same results were found between PQ/MQ-SeET and PQ/*** SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two *** clinical pregnancy outcomes could be obtained by transferring good-quality embryos,no matter whether in SeET or *** quality plays a more important role in pregnancy outcomes for RIF patients.

关键词： recurrent implantation failure sequential embryo transfer frozen-thawed embryo transfer embryo transfer strategies