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Reduction of dinitrogen to ammonia on doped three-atom clusters Nb_(2)M(M=Sc to Cu & Y to Ag)

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Rare Metals 2024年第8期43卷 3810-3818页

作者： Ran Cheng Chao-nan Cui Zhi-Xun luo Beijing National Laboratory for Molecular Science(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was *** key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was *** examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy Nitrogen fixation Ammonia synthesis Theoretical calculations

Study on carbon emission calculation method and carbon reduction indexes of urban building stock

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Science China(Technological Sciences) 2024年第9期67卷 2706-2726页

作者： YANG Liu ZHANG nan LU Mei luo ZhiXing DOU Mei State Key Laboratory of Green Building Xi’an University of Architecture and TechnologyXi’an 710055China School of Architecture Xi’an University of Architecture and TechnologyXi’an 710055China School of Language Literature and LawXi’an University of Architecture and TechnologyXi’an 710055China School of Management Xi’an University of Architecture and TechnologyXi’an 710055China China Southwest Architectural Design and Research Institute Corp.Ltd. Chengdu 610041China

Carbon emissions associated with buildings are a major source of urban emissions. To put forward the methods and strategies to curb carbon emissions from urban building stock, it is not only necessary to establish a carbon emission calculation method for fine statistical analysis, but also to evaluate carbon emissions of urban planning schemes with applicable indexes. Currently,researches mainly focus on carbon emissions of individual buildings. When expanded to urban building stock, the calculation faces the lack of basic data, inadequate spatial analysis and unspecific carbon reduction indexes. Therefore, this study proposes a bottom-up calculation method for urban building stock, conducts spatial analysis based on carbon balance of urban grids, reveals the coupling mechanism between urban carbon reduction indexes and grid carbon emissions, and systematically establishes a carbon-reduction-oriented urban planning method that comprises calculation, analysis and evaluation, which is applied to Xi'an,China. This study provides a theoretical reference for cities to formulate carbon reduction targets and implement planning strategies by evaluating and predicting carbon emissions from urban building stock.

关键词： carbon emissions urban building stock calculation method carbon reduction index

Tianxia Qingshi(World Circumstances)in the Political World of Traditional Chinese Scholar Officials:A Case Study of the“Green Sprouts Policy Polemic”in the Early Xining Period of the Northern Song

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Social Sciences in China 2024年第1期45卷 89-105页

作者： luo Yi'nan School of Government Peking University

How to deal with differences is a question that any political body must respond *** individualist perspective emphasizes that actors will adopt measures to exclude or even eliminate divergent claims in order to gain control over interests power or statutory policy,but the rich experience of traditional Chinese scholar officials offers the possibility of going beyond the limitations of this *** perspective of“tianxia qingshi(world circumstances)”as a new narrative reveals a unique practical logic and dynamic mechanism in Chinese political civilization that have been overlooked by the individualist ***“Green Sprouts policy(qing miao fa)polemic”in the early years of the New Policies era of the Northern Song dynasty(960-1127)presents a historical situation that has not been given full attention by existing research.

关键词： tianxia qingshi(world circumstances) “Green Sprouts policy polemic ”dispute practice scholar-official politics

Effects of seepage pressure on the mechanical behaviors and microstructure of sandstone

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2033-2051页

作者： Xuewei Liu Juxiang Chen Bin Liu sai Wang Quansheng Liu Jin luo State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Faculty of Engineering China University of GeosciencesWuhan430074China Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China

Surrounding rocks of underground engineering are subjected to long-term seepage pressure,which can deteriorate the mechanical properties and cause serious *** order to understand the impact of seepage pressure on the mechanical property of sandstone,uniaxial compression tests,P-wave velocity measurements,and nuclear magnetic resonance(NMR)tests were conducted on saturated sandstone samples with varied seepage pressures(i.e.0 MPa,3 MPa,4 MPa,5 MPa,6 MPa,7 MPa).The results demonstrate that the mechanical parameters(uniaxial compressive strength,peak strain,elastic modulus,and brittleness index),total energy,elastic strain energy,as well as elastic strain energy ratio,decrease with increasing seepage pressure,while the dissipation energy and dissipation energy ratio ***,as seepage pressure increases,the micro-pores gradually transform into meso-pores and *** increases the cumulative porosity of sandstone and decreases P-wave *** numerical results indicate that as seepage pressure rises,the number of tensile cracks increases progressively,the angle range of microcracks is basically from 50-120to 80-100,and as a result,the failure mode transforms to the tensile-shear mixed failure ***,the effects of seepage pressure on mechanical properties were *** results show that decrease in the effective stress and cohesion under the action of seepage pressure could lead to deterioration of strength behaviors of sandstone.

关键词： Rock mechanics Mechanical property Seepage pressure Numerical simulation Microcracks

Single-step-etched ultra-compact metamaterial grating coupler enabled by a hierarchical inverse design approach

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 119-126页

作者： Qiao Wang Ruiqi luo nan Liu Maojing Hou Bo Xiong Guandong Liu Wei Ma Intelligent Network Research Institute Zhejiang LabHangzhou 311100China State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic EngineeringZhejiang UniversityHangzhou 310027China

With the concept of metamaterials introduced into integrated photonics,subwavelength structures have gained popularity for their ability to create devices with ultra-compact size,high performance,and versatile ***,traditional metamaterial design methods are usually based on empirical templates and physical approximations,lacking the ability to design free-form metamaterial structures and optimize entire devices *** this work,we propose a hierarchical inverse design approach that combines a conventional effective refractive index based metamaterial structures design with a follow-up global topology *** empirical metamaterial grating coupler design based on effective refractive index engineering faces inaccurate index extraction and insufficient approximation of wavevector matching conditions,which deteriorates coupling efficiency,especially for fully-etched devices with the decreased tapering ***,a subsequent overall topology optimization step can well compensate for the negative effect of the shrinking device footprint to increase the efficiency of the metamaterial grating *** demonstrate a 23μm×10μm ultra-compact metamaterial grating coupler with single-stepetched to couple light between a fiber and a 500 nm single-mode silicon waveguide in the *** measurement shows an insertion loss of 3.17 dB and a 3 dB bandwidth of 77 nm,making it the smallest footprint device ever reported.

关键词： waveguide hierarchical inverse

Prophylactic effects of Edible Lilium-Egg yolk compound powder on depression-like behaviors in rats exposed to chronic unpredictable mild stress: A role of gut-brain axis

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Food Science and Human Wellness 2024年

作者： Yu Huang Yu-xin luo sai-nan Tian Meng-zhou Xie Liang Li Ming-xing Jiang Zhi-ying Yuan Hunan University of Chinese Medicine Key Laboratory of TCM Heart and Lung Syndrome Differentiation & Medicated Diet and Dietotherapy， Hunan University of Chinese Medicine TCM and Ethnomedicine Innovation & Development International Laboratory， School of Pharmacy， Hunan University of Chinese Medicine

The incidence rate and harmfulness of depression are increasing yearly， and the research on the antidepressant effect of regulating the intestinal microecology balance has attracted widespread attention. The purpose of this research was to study the preventive effects and the regulatory mechanism of edible Lilium-egg yolk compound powder(Chinese abbreviation， BHT) on gut-brain crosstalk in depressive rats induced by chronic unpredictable mild stress(CUMS) through the "microbiota-gut-brain" axis. Results showed that infusion of BHT for 21 days ameliorated the morphology of the hippocampus and colon， increased the rate of sucrose preference， reduced the immobility time of forced swimming， increased the expression level of anti-inflammatory cytokine Interleukin-10 (IL-10) in serum， up-regulate the expression level of plasma neurotransmitter 5-hydroxy tryptamine (5-HT)， down-regulate the expression of inflammatory factors tumor necrosis factor-α (TNF-α)， interleukin-6 (IL-6)， and interleukin-1β (IL-1β) and neurotransmitter glutamic acid (Glu) in serum， and decrease the expression levels of lipopolysaccharide (LPS)， diamine oxidase (DAO) and lactate dehydrogenase (LD) in plasma. The underlying mechanism may be to reduce the activation of microglia (lower levels of CD11b， IBa1 protein and gene expression)， regulate hippocampal GR/BDNF/NPY signal pathway (higher levels of GR， BDNF， NPY protein and gene expression)， enhance intestinal mucosal barrier function (higher levels of ZO-1， Occludin protein and gene expression)， regulate the composition and structure of intestinal flora(Analysis results of LEfSe combined with random forest showed that Prevotella and Paraprevotella might be biomarkers of BHT intervention in depression)， and it is related to the improvement of glutathione metabolism， and other metabolic pathways. Pearson correlation analysis found that 5-HT is strongly positively correlated with Prevotella，and Glu has a strong negative correlation with ***

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Potential therapeutic role of spermine via Rac1 in osteoporosis:Insights from zebrafish and mice

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Zoological Research 2024年第2期45卷 367-380页

作者： Rui-Xue Jiang nan Hu Yu-Wei Deng Long-Wei Hu Hao Gu nan luo Jin Wen Xin-Quan Jiang Department of Prosthodontics Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China College of Stomatology Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Research Institute of StomatologyShanghai Engineering Research Center of Advanced Dental Technology and MaterialsShanghai 200125China Department of Endodontics Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai Jiao Tong UniversityShanghai 200011China Department of Oral and Maxillofacial-Head and Neck Oncology Shanghai Ninth People’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200011China Department of Preventive Dentistry Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai Jiao Tong UniversityShanghai 200011China

Osteoporosis(OP)is a prevalent metabolic bone *** drug therapy is essential to prevent bone loss in osteoporotic patients,current treatments are limited by side effects and high costs,necessitating the development of more effective and safer targeted *** a zebrafish(Danio rerio)larval model of osteoporosis,we explored the influence of the metabolite spermine on bone *** showed that spermine exhibited dual activity in osteoporotic zebrafish larvae by increasing bone formation and decreasing bone *** not only demonstrated excellent biosafety but also mitigated prednisolone-induced embryonic neurotoxicity and ***,spermine showcased protective attributes in the nervous systems of both zebrafish embryos and *** the molecular level,Rac1 was identified as playing a pivotal role in mediating the antiosteoporotic effects of spermine,with P53 potentially acting downstream of *** findings were confirmed using mouse(Mus musculus)models,in which spermine not only ameliorated osteoporosis but also promoted bone formation and mineralization under healthy conditions,suggesting strong potential as a bonestrengthening *** study underscores the beneficial role of spermine in osteoporotic bone homeostasis and skeletal system development,highlighting pivotal molecular *** their efficacy and safety,human endogenous metabolites like spermine are promising candidates for new anti-osteoporotic drug development and daily bone-fortifying agents.

关键词： Osteoporosis Spermine Rac1 Zebrafish Mice

Ketogenic diet therapy in children with epilepsy caused by SLC2A1 mutations:a single-center single-arm retrospective study

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World Journal of Pediatrics 2024年第5期20卷 517-524页

作者： Ying-Yan Wang Yun-Qing Zhou Li-Juan luo Cui-Jin Wang nan Shen Hao Li Ji-Wen Wang Department of Neurology Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Infectious Diseases Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Clinical Research Ward Clinical Research CenterShanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

Background This retrospective study assessed the efficacy and safety of ketogenic diet therapies in children with epilepsy caused by SLC2A1 genetic mutations and glucose transporter type 1 deficiency *** Pediatric patients with epilepsy symptoms admitted to our medical center between January 2017 and October 2021 were included if they presented with an SLC2A1 genetic mutation on whole-exome *** analyzed the patients’convulsions and treatment with antiepileptic *** patients were followed up at different time periods after ketogenic diet *** Six patients with SLC2A1 mutations were included in this *** patients had seizures of different types and frequencies,and they took antiepileptic drugs to relieve their *** were then treated with a ketogenic diet for at least four *** analyzed epilepsy control rates at 1,2,3,6,and 12 months after ketogenic diet *** patients were seizure-free within a month of receiving the diet *** patients were followed up for six months,three were followed up for 12 months after the treatment,and there was no recurrence of epilepsy during this *** antiepileptic drug withdrawal,none of the patients experienced seizure relapse when receiving ketogenic diet treatment *** severe adverse events occurred during the *** Ketogenic diet therapy is very effective and safe for the treatment of epilepsy caused by SLC2A1 ***,patients with glucose transporter type 1 deficiency syndrome caused by SLC2A1 mutations should begin ketogenic diet treatment as soon as possible.

关键词： Epilepsy Glucose transporter type 1 Ketogenic diet SLC2A1

Pollutant emissions from biomass burning:A review on emission characteristics,environmental impacts,and research perspectives

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Particuology 2024年第2期85卷 296-309页

作者： Ke Jiang Ran Xing Zhihan luo Wenxuan Huang Fan Yi Yatai Men nan Zhao Zhaofeng Chang jinfeng Zhao Bo Pan Guofeng shen College of Urban and Environmental Sciences Peking UniversityBeijing100871China Beijing Key Lab Plant Resources Research and Development Beijing Technology and Business UniversityBeijing100048China College of Ecology and Environment Zhengzhou UniversityZhengzhou450001China Facultyof Environmental Sciences and Engineering Kunming University of Science and TechnologyYunnan Provincial Key Laboratoryof Soil Carbon Sequestration and Pollution ControlKunming650500China Institute of Carbon Neutrality Peking UniversityBeijing100871China

Biomass is one most abundant resource on the earth providing important energies in support of so-cioeconomic development in many *** of biomass fuels comprises to nearly 10%of the total energy from anthropogenic combustion processes:however,as the burning is usually incomplete,this process yields products of incomplete combustion posing consequently significant impacts on air quality,human health,and climate ***,we analyzed spatiotemporal characteristics in intentional and unintentional biomass burning from different sectors,discussed impacts of biomass burning emissions on indoor and outdoor air quality,and consequent influences on human *** global total con-sumption amount of biomass including both natural and anthropogenic sources was approximately 7900 Tg in 2019,with significantly large regional and sectorial discrepancies among ***,anthropogenic biomass burning amounts increased gradually,but notably in some developing countries like China residential consumption of biomass fuels,as one large sector of biomass use,decreased over *** biomass consumption needs to be accurately *** are relatively rich datasets of pollutant emission factors from biomass burning,including laboratory and field tests,but still large variations exit and contribute substantially to the uncertainty in emission *** pri-mary PM2.5,black carbon and organic carbon emissions from biomass burning were about 51,4.6,and 29 Tg,respectively,contributing to nearly 70%,55%,and 90%of the total emission from all sources,and emissions from the residential sector and open fires are major *** carbon emissions from biomass burning attracts growing interests but available studies adopted different methodologies challenging the comparability of those *** burning emissions polluted not only ambient air but more severely indoor air quality,adversely affecting human *** studies that should be emphasiz

关键词： Biomass burning Carbonaceous aerosol Emission Air quality Human health