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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang Wen-Bo He Xiu-Qin hu peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

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Mangrove wetlands distribution status identification, changing trend analyzation and carbon storage assessment of China

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China Geology 2024年第1期7卷 1-11页

作者： Chang Li Fu Wang peng Yang Fei-cui Wang yun-zhuang hu Yan-lin Zhao Li-zhu Tian Rui-bin Zhao Tianjin Center(North China Center of Geoscience Innovation) China Geological Survey(CGS)Tianjin 300170China Tangshan Hydrological Survey and Research Center of Heibei Province Tangshan063000China Key Laboratory of Coast Geo-Environment China Geological SurveyCGSTianjin 300170China Tianjin Key Laboratory of Coast Geological Processes and Environmental Safety Tianjin 300170China

This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s *** interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software ***,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST *** show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and *** total carbon storage is assessed at 2.11×10^(6) t,with specific regional data *** since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in *** important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove *** study is poised to guide future mangroverelated investigations and conservation strategies.

关键词： Mangrove Wetland Carbon storage Ecological conservation ArcGIS software platform Restoration InVEST model Quantitative analysis Coastal zone of China

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Optimizing magnetoelastic properties by machine learning and high-throughput micromagnetic simulation

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Rare Metals 2024年第5期43卷 2251-2262页

作者： Jian-hu Gong Zheng-Ming Zhang Cheng-Liang Zhang peng-Qiang hu Chao Zhou Dun-hui Wang Sen Yang Division of Microelectronic Materials and Devices Hangzhou Dianzi UniversityHangzhou 310018China School of Physics MOEKey Laboratory forNonequilibrium Synthesis and Modulation of Condensed Matter and State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

Magnetoelastic couplings in giant magnetostrictive materials(GMMs)attract significant interests due to their extensive applications in the fields of spintronics and energy harvesting *** the role of the selection of materials and the response to external fields is essential for attaining desired functionality of a ***,machine learning(ML)models are conducted to predict saturation magnetostrictions(λ_(s))in RFe_(2)-type(R=rare earth)GMMs with different *** to ML-predicted composition–λsrelations,it is discovered that the values ofλshigher than1100×10^(-6)are almost situated in the composition space surrounded by 0.26≤x≤0.60 and 1.90≤y≤2.00 for the ternary compounds of Tb_(x)Dy_(1-x)Fe_(y).Assisted by ML predictions,the compositions are further narrowed down to the space surrounded by 0.26≤x≤0.32 and 1.92≤y≤1.97 for the excellent piezomagnetic(PM)performance in the Tb_(x)Dy_(1-x)Fe_(y)based PM device through our developed high-throughput(HTP)micromagnetic simulation(MMS)***,high sensitivities up to10.22-13.61 m T·MPa^(-1)are observed in the optimized range within which the available experimental data fall *** work not only provides valuable insights toward understanding the mechanism of magnetoelastic couplings,but also paves the way for designing and optimizing highperformance magnetostrictive materials and PM sensing devices.

关键词： Magnetostriction Piezomagnetic effect Machine learning Micromagnetic simulation

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Advanced modeling of the absorption enhancement of black carbon particles in chamber experiments by considering the morphology and coating thickness

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FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING 2024年第9期18卷 116-0页

作者： Wei, Xiaodong hu, Jianlin Liu, Chao Xie, Xiaodong Yin, Junjie Guo, Song hu, Min peng, Jianfei Wang, huijun Nanjing Univ Informat Sci & Technol Collaborat Innovat Ctr Atmospher Environm & Equip Sch Environm Sci & Engn Jiangsu Key Lab Atmospher Environm Monitoring & P Nanjing 210044 Peoples R China Nanjing Univ Informat Sci & Technol Collaborat Innovat Ctr Forecast & Evaluat Meteoro Key Lab Meteorol Disaster Minist Educ Nanjing 210044 Peoples R China Chinese Acad Sci Inst Atmospher Phys Nansen Zhu Int Res Ctr Beijing 100029 Peoples R China East China Air Traff Management Bur CAAC Shanghai 200335 Peoples R China Peking Univ Coll Environm Sci & Engn State Key Joint Lab Environm Simulat & Pollut Con Int Joint Lab Reg Pollut Control IJRCMinist Educ Beijing 100871 Peoples R China Nankai Univ Coll Environm Sci & Engn Tianjin Key Lab Urban Transport Emiss Res Tianjin 300071 Peoples R China Nankai Univ Coll Environm Sci & Engn State Environm Protect Key Lab Urban Ambient Air Tianjin 300071 Peoples R China

Measurements studies have shown that the absorption of radiation by black carbon (BC) increases as the particles age. However, there are significant discrepancies between the measured and modeled absorption enhancement (E-abs), largely due to the simplifications used in modeling the mixing states and shape diversities. We took advantage of chamber experiments on BC aging and developed an efficient method to resolve the particle shape based on the relationship between the coating fraction (Delta D-ve/D-ve,D-0) and fractal dimension (D-f), which can also reflect the variations of D-f during the whole BC aging process. BC with externally and partly mixed states (0 0.5). The morphological parameters (i.e., the effective density and the dynamic shape factor) were compared with the measured values to verify the simulated morphology. The simulated mean deviations of morphological parameters were smaller than 8% for the method resolving the particle shape. By applying a realistic shape and refractive index, the mass absorption cross for fully mixed states can be improved by 11% compared with a simplified core-shell model. Based on our understanding of the influence of D-f and Delta D-ve/D-ve,D-0 on E-abs, we propose a two-stage calibration equation to correct the E-abs values estimated by the core-shell model, which reduces the simulation error in the Mie calculation by 6%-14%. (c) Higher Education Press 2024

关键词： Black carbon Mixing states Fractal dimension Dynamic shape factor Absorption enhancement OH-INITIATED OXIDATION OPTICAL-PROPERTIES LIGHT-ABSORPTION EFFECTIVE DENSITY SOOT PARTICLES BROWN CARBON MIXING STATE AEROSOLS URBAN COMBUSTION

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Carbonation of Dicalcium Silicate Enhanced by Ammonia Bicarbonate and Its Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 69-74页

作者：周浩刘鹏 WANG Fazhou hu Chuanlin School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

The strength development law of γ-type dicalcium silicate (γ-C_(2)S) under different carbonation processes was investigated,and the carbonation mechanism of γ-C_(2)S under the action of NH_(4)HCO_(3) was clarified by using a wide range of test methods,including XRD and SEM.A method of saturated NH_(4)HCO_(3) solution as a curing agent was identified to improve the carbonation efficiency and enhance the carbonation degree of γ-C_(2)S,and then a high-strength carbonated specimen was *** analysis and SEM morphology analysis were conducted on the carbonised specimens obtained under atmospheric pressure carbonisation conditions using the curing *** was found that γ-C_(2)S could perform carbonisation well under atmospheric pressure,which promoted the carbonisation efficiency and decreased the carbonisation cost ***,a new carbonisation process solution was proposed for the rapid carbonisation of γ-C_(2)S.

关键词： type dicalcium silicate carbonization process curing agent atmospheric carbonization

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Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU Shi-peng YANG Wen-zhi GAO Min hu Shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

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Experimental and first-principles calculation of TiN growth mechanism on CeAlO_(3) surface in steel

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Journal of Iron and Steel Research International 2024年第2期31卷 452-463页

作者： Fei-hu He Jun peng Fang Zhang Yong-bin Wang Hong-tao Chang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina

Regular TiN is harmful to the toughness of steel,and its shape and size need to be *** the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the *** results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic *** calculation results indicate that there is no metallic bonding present in the CeAlO_(3) *** the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.

关键词： CeAlO_(3)-TiN inclusion Orientation relationship Crystal structure First principle Surface energy

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Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1110-1119页

作者： Xiao-Wei Ouyang Sheng Fang yun-Min Yi Shi-peng Zou Qi-Yu hu Zi-Xuan huang Qing-Xia Li Jin-Yan Luo Department of Ophthalmology Nanchang Hongdu Hospital of Traditional Chinese MedicineNanchang 330000Jiangxi ProvinceChina Department of Ophthalmology Jiangxi Hospital of Integrated Traditional Chinese and Western MedicineNanchang 330000Jiangxi ProvinceChina Department of Cataract Nanchang University Affiliated Eye HospitalNanchang 330000Jiangxi ProvinceChina Department of Neuro-ophthalmology Nanchang University Affiliated Eye HospitalNanchang 330000Jiangxi ProvinceChina

AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web of Science,Cochrane,SinoMed,CNKI,Wanfang Database,CQVIP,and Chinese journals databases between inception and July *** standardized mean differences(SMD)or weighted mean difference(WMD)with 95%confidence intervals(CI)from RCTs evaluating Schirmer’s I test(SIT),corneal fluorescein staining score(CFS),tear breakup time(TBUT),DES score(DESS),and Ocular Surface Disease Index(OSDI)were *** analysis,Egger’s test and Meta-regression analysis were performed for all ***:We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria,involving 1796 ***-concentrations group significantly improved the outcome of CFS according to random effects modelling(SMD,-3.37;95%CI,-5.25 to-1.48;P=0.0005).The rest of the results were not statistically significant,including indicators such as SIT,TBUT,DESS and ***:For dry eyes with positive corneal staining,a high concentration of HY is recommended,whereas in other cases,a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes.

关键词： dry eye hyaluronic acid concentration Meta-analysis

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Boring holes in Au nanoplates by active surface etching

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Nano Research 2024年第9期17卷 8610-8617页

作者： Haiyang hu yuntao Wang Qian Wang Xudong peng An Su Hong Wang Hongyu Chen Institute of Advanced Synthesis(IAS)and School of Chemistry and Molecular Engineering Jiangsu National Synergetic Innovation Centre for Advanced MaterialsNanjing Tech UniversityNanjing 211816China Department of Environmental Science and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry School of Science and Key Laboratory for Quantum Materials of Zhejiang ProvinceResearch Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

In contrast to the conventional etching that makes nanoparticles rounder and our previous sharpening etching mode that causes serrated edges,here,we developed a new boring etching mode that targets the faces of Au nanoplates to make *** critical factors are the pre-incubation step with the ligand 2-mercapto-5-benzimidazolecarboxylic acid(MBIA)and the subsequent removal of excess ligands in the ***,etching is focused onto the few sites with initial loss of ligands,which cannot be quickly *** choice of ligand MBIA is also of importance,as it carries negative charge and repels each *** inability of forming a dense layer probably plays a critical role in the site-selectivity for faces,because ligands at the higher curvature edges and corners are expected to have less *** etching results from the comproportionation reaction between Au3+and Au0 in the nanoplates,where Br-coordination to Au and the extra stabilization from cetyltrimethylammonium bromide(CTAB)are *** believe that the ability of boring holes is an important tool for future synthetic designs.

关键词： Au nanoplates active surface etching boring etching mode cetyltrimethylammonium bromide(CTAB)passivation holes

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Fast thermal responsive separators toward long-life and safe lithium metal batteries

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Nano Research 2024年第4期17卷 2746-2754页

作者： Pingan Li Zhifang Liu Yitong peng Shanshan Yang Tao Meng yunhuan hu Yingjun Jiang Hao Sun Qi Li Xianluo hu State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Lithium metal batteries(LMBs)have been extensively investigated during the past decades because of their ultrahigh energy *** the increasing demand for energy density,however,the safety issue of LMBs has become a significant *** particular,localized areas of increased temperature(namely,hotspots)may be induced and even exacerbated within LMBs by uneven current distribution,internal short circuits,or inadequate heat dissipation,which significantly sacrifices battery safety and cycle ***,we report the rational design and fabrication of a fast thermal responsive separator capable of inhibiting the growth of lithium dendrites and mitigating thermal propagation,thereby reducing the risk of thermal *** as-achieved separator comprises both an electrospun membrane using a phase change material with superior thermal-storage ability and a thermally conductive modification layer of hexagonal boron nitride nanosheets with a fast heat-transfer *** is demonstrated that such a unique integration of heat conduction and heat storage enables the functional separator with attractive abilities to mitigate hotspots and inhibit the growth of lithium dendrites upon the cycling of ***,pouch cells with the thermal-responsive separator,as well as numerical simulations,verify much enhanced safety and cycle life of *** work may offer a new conceptual design of intelligent separators that acts as a functional unit encapsulated within a single cell to boost in-situ thermal management,which will help to develop high-safety and energy-dense LMBs.

关键词： lithium metal batteries separators hotspots safety thermal management

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