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Redox-Active Dihydrophenazine-Based Macrocycle:Synthesis,Conformation-Adaptive Behavior and Host-Guest Complexation with Tetracyanoquinodimethane

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Chinese Journal of Chemistry 2024年第16期42卷 1895-1900页

作者： Qiong-Yan Hong Bin Huang Meng-xiang Wu Lin Xu Xiao-Li Zhao Xueliang shi hai-Bo Yang Shanghai Key Laboratory of Green Chemistry and Chemical Processes State Key Laboratory of Petroleum Molecular&Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal University3663 N.Zhongshan RoadShanghai 200062China

A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and *** the one hand,the macrocycle showed host-guest interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between ***,host-guest complexation was accompanied by fluorescence quenching and conformational change of the *** the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the guest molecule TCNQ,thereby accomplishing reversible binding ***,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-guest chemistry.

关键词： Dihydrophenazine Macrocycle Conformational adaptation Redox-active Host-guest interactions Charge transfer interaction Organic radical Supramolecular chemistry

A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques

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Research in Astronomy and Astrophysics 2024年第1期24卷 245-264页

作者： shi-hai Yang Bo Xu Xin Li School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China

As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is ***, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission.

关键词： minor planets asteroids:general celestial mechanics Planetary Systems

Preparation and properties of ZrO_(2)-strengthened porous mullite insulation materials using Y_(2)O_(3) additive

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Journal of Iron and Steel Research International 2024年第6期31卷 1514-1521页

作者： Wang-zhi Yu Yi-hong shi Ping Liu Yong-wan Wu Cheng-hao Song Xian-gong Deng xiang Ding Song-lin Ran Yi Zhang hai-jun Zhang hai-liang Deng Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa'anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrO_(2)-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO_(4) and Al_(2)O_(3) as primary materials and Y_(2)O_(3) as an *** effects of Y_(2)O_(3) contents on the phase composition,microstructure,mechanical properties,and heat conductivity of the porous mullite insulation materials were investigated.A suitable Y_(2)O_(3) content could promote phase transition of monoclinic ZrO_(2)(m-ZrO_(2))to tetragonal ZrO_(2)(t-ZrO_(2)),reduce pore size,and improve the strengths of as-prepared *** cold crushing strength and bending strength of as-prepared specimens with a 119µm spherical pore size using 6 wt.%Y_(2)O_(3) were 35.2 and 13.0 MPa,respectively,with a heat conductivity being only 0.248 W/(m K).

关键词： Porous mullite insulation material Zirconium oxide Y_(2)O_(3) Mechanical property Heat conductivity

An ecological perspective on Joseph Rock’s(1884-1962)plant collection activities in China

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Journal of Plant Ecology 2024年第4期17卷 100-113页

作者： Jifan Luo Ruozhi Huang hai Yan Renwu Wu Shuai Liao Zhoubing xiang Yongxi Zou Liangchen shi Ke Wang Zhiyi Bao College of Landscape Architecture Zhejiang Agriculture and Forestry UniversityHangzhou 311300China Zhejiang Agriculture and Forestry University Landscape Architecture Institute Hangzhou 311300China South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650China

In the early 20th century,numerous western botanists,often referred to as‘plant hunters’,embarked on ambitious expeditions to China,playing a crucial role in the study of botany and botanical *** their contributions,comprehensive assessments of their explorations are *** bridge this gap,this article focuses on the work of Joseph Charles Francis Rock,a notable figure in that *** work revisits Rock’s botanical expeditions within the broader context of botanical diversity *** outlines his historical experiences in collecting plants in China and enumerates the species composition and phenotypic traits of the plants he ***,it also analyzes the spatial distribution of the species,the completeness of his collection and the α-and β-diversity of the plants he *** findings reveal that Rock led four major botanical expeditions in China between 1922 and 1933,amassing a total of 28184 sheets and 16608 numbers across 204 families,1081 genera and 4231 *** focus was predominantly on ornamental species,which exhibit a variety of flower colors and *** collection work spanned 5 provinces,35 cities and 72 counties,with a notable concentration in the Hengduan Mountains,a current biodiversity *** study not only reconstructs Rock’s botanical legacy but also offers valuable historical data and fresh analytical insights for understanding contemporary plant *** contributes to the ongoing discourse on the importance of preserving plant diversity as a cornerstone of environmental sustainability.

关键词： Joseph Charles Francis Rock plant specimen collection history plant diversity plant collector

Privacy-Preserving Frank-Wolfe on Shuffle Model

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 887-907页

作者： Ling-jie ZHANG shi-song WU hai ZHANG School of Mathematics Northwest UniversityXi’an 710127China School of Mathematics and Information Science Baoji University of Arts and SciencesBaoji 721013China China Southern Power Grid Artificial Intelligence Technology Company Limited Guangzhou 510700China

In this paper,we design the differentially private variants of the classical Frank-Wolfe algorithm with shuffle model in the optimization of machine *** weak assumptions and the generalized linear loss(GLL)structure,we propose a noisy Frank-Wolfe with shuffle model algorithm(NoisyFWS)and a noisy variance-reduced Frank-Wolfe with the shuffle model algorithm(NoisyVRFWS)by adding calibrated laplace noise under shuffling scheme in thel_(p)(p∈[1,2])-case,and study their privacy as well as utility guarantees for the H?lder smoothness *** particular,the privacy guarantees are mainly achieved by using advanced composition and privacy amplification by *** utility bounds of the Noisy FWS and NoisyVRFWS are analyzed and obtained the optimal excess population risksO(n-(1+α/4α+log(d)√log(1/δ)/n∈and O(n-1+α/4α+log(d)√log1(+δ)/n^(2)∈with gradient complexity O(n(1+α)^(2)/4α^(2)forα∈[1/√3,1].It turns out that the risk rates under shuffling scheme are a nearly-dimension independent rate,which is consistent with the previous work in some *** addition,there is a vital tradeoff between(α,L)-Holder smoothness GLL and the gradient *** linear gradient complexity O(n)is showed by the parameterα=1.

关键词： differential privacy Frank-Wolfe algorithm privacy amplification shuffle model

Atomic-Scale Insights into Damage Mechanisms of GGr15 Bearing Steel Under Cyclic Shear Fatigue

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1265-1278页

作者： Qiao-Sheng Xia Dong-Peng Hua Qing Zhou Ye-Ran shi xiang-Tao Deng Kai-Ju Lu hai-Feng Wang Xiu-Bing Liang Zhao-Dong Wang State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an710072China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Alternating shear stress is a critical factor in the accumulation of damage during rolling contact fatigue,severely limiting the service life of ***,the specific mechanisms responsible for the cyclic shear fatigue damage in bearing steel have not been fully *** the mechanical response and microstructural evolution of a model GGr15 bearing steel under cyclic shear loading are investigated through the implementation of molecular dynamics *** samples undergo 30 cycles under three different loading conditions with strains of 6.2%,9.2%,and 12.2%,*** findings indicate that severe cyclic shear deformation results in early cyclic softening and significant accumulation of plastic damage in the bearing ***,samples subjected to higher strain-controlled loading exhibit higher plastic strain energy and shorter fatigue ***,strain localization is identified as the predominant damage mechanism in cyclic shear fatigue of the bearing steel,which accumulates and ultimately results in fatigue ***,simulation results also revealed the microstructural reasons for the strain localization(e.g.,BCC phase transformation into FCC and HCP phase),which well explained the formation of white etching *** study provides fresh atomic-scale insights into the mechanisms of cyclic shear fatigue damage in bearing steels.

关键词： Cyclic shear fatigue Molecular dynamic simulation Bearing steels Plastic damage accumulation

Coordination-driven self-assembly of a molecular 818knot and molecular borromean rings

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Science China Chemistry 2024年第11期67卷 3652-3656页

作者： xiang Gao Dong Liu hai-Ning Zhang Guo-Xin Jin Department of Chemistry Fudan University

We report the facile construction of a molecular 818knot and a molecular Borromean rings assembly through self-assembly directed by Cp*Rh corner units. Two curved ligands of similar size and shape were used in this study. The slight steric differences between the two ligands induce the formation of distinctly different topologies of the assembled products. The structures were confirmed by single-crystal X-ray analysis and nuclear magnetic resonance spectroscopy.

关键词： coordination-driven Cp*Rh 818 knot Borromean rings

Consensus on glycemic management for patients with coronary heart disease and type 2 diabetes

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Journal of Geriatric Cardiology 2024年第7期21卷 689-702页

作者： Li-Nong JI Yun-Dai CHEN Jing LIU xiang-hai ZHOU Cardiovascular Subcommittee of Chinese International Exchange and Promotion Association for Medical and Healthcare Peking University People's Hospital Chinese PLA General Hospital

The prevalence of patients with coronary heart disease(CHD)and diabetes mellitus is notably high,posing sig-nificant residual cardiovascular risks even after routine interventions such as antihypertensive,lipid-lowering,and antithrombot-ic *** studies have demonstrated that certain glucose-lowering medications confer cardiovascular benefits for pa-tients with type 2 ***,a survey indicates that cardiologists may not be fully acquainted with the optimal screen-ing timing,indicators,and diagnostic criteria for type 2 diabetes,and there is insufficient awareness and a low rate of prescrip-tion of novel glucose-lowering medications with proven cardiovascular efficacy,such as glucagon-like peptide-1 receptor agon-ists(GLP-1 RAs)and sodium-glucose co-transporter-2 inhibitors(SGLT-2i).In this context,based on domestic and international guidelines or consensus and the latest evidence-based evidence,this consensus aims to standardize the glycemic management for patients with acute coronary syndrome,chronic coronary syndrome,and perioperative management for percutaneous coronary *** highlights the key points of screening and diagnosis of type 2 diabetes,and the comprehensive management of cardiovascular risk in patients with *** consensus elaborates on the principles and algorithms of glycemic management for CHD patients,without involving acute complications of diabetes,clarifies the clinical practice of glucose-lowering medications with cardiovascular benefits,and promotes the standardized use of these medications in cardiovascular and other related spe-cialty ***,it addresses the glucose-lowering treatment to comprehensively reduce cardiovascular risks.

关键词： coronary patients routine

Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H

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Acta Geochimica 2024年第2期43卷 385-398页

作者： Jianzhao Yin Yuhong Chao Haoyu Yin Hongyun shi Shoupu xiang Wuhan Institute of Technology Wuhan 430074China College of Earth Sciences Jilin UniversityChangchun 130061China Ganzhongnan Institute of Geology and Mineral Exploration Nanchang 330002China Guinea Westfi eld Mining Company-Sarlu Jinzhong 031300China Orient Resources Ltd. RichmondB.C.V7E 1M8Canada Silvercorp Metals Inc. Beijing 100027China

By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic *** δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly *** to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will *** other words,mantle-derived solutions can have extremely low hydrogen isotope *** means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the *** formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma.

关键词： Carbon oxygen and hydrogen isotopes Origin Independent tellurium deposit The Qinghai–Xizang Plateau