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Enantioselective reductive conjugate alkenylation ofα,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei luo Qiu-Quan Pan Qi-Wei Yao Xing-zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis,yet their asymmetric variant remains ***,asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–*** manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl *** method facilitates the enantioselective addition of keto alkenyl groups toα,β-enones,resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access *** use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

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Influencing factors of early post-traumatic stress disorder in young and middle-aged individuals with open globe injuries in west China:a cross-sectional study

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 146-153页

作者： Yi-Man Li Xin zhang Ji-Hong zeng Hong-Mei luo Department of Ophthalmology West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To evaluate the prevalence of early post-traumatic stress disorder(PTSD)among young and middle-aged patients who have suffered open globe injuries,and to identify the psychosocial factors influencing PTSD in these ***:A total of 280 patients who underwent ocular trauma surgery between January 2023 and January 2024 were selected through convenience *** were collected using a custom-designed demographic questionnaire,the Connor-Davidson Resilience Scale(CDRISC),the Cognitive Emotion Regulation Questionnaire(C-ERRI),and the PTSD Checklist-Civilian Version(PCL-C).Univariate analysis and stepwise multiple linear regression analysis were performed to determine the factors affecting PTSD in these ***:The average PTSD score for the patients was 33.22±*** scores for individual PTSD dimensions,ranked from highest to lowest,were recurrent traumatic experiences,heightened arousal,avoidance reactions,and social *** PTSD symptoms were observed in 85 patients(30.36%).Univariate analysis indicated that gender,postoperative vision,marital status,psychological resilience,and rumination were significant factors affecting PTSD symptoms(χ^(2)/t=6.53,17.88,8.83,2.17,and 14.1,respectively;all P<0.05).Pearson correlation analysis showed a positive correlation between rumination and PTSD symptoms(r=0.73,P<0.01)and a negative correlation between psychological resilience and PTSD symptoms(r=-0.14,P<0.05).Stepwise multiple linear regression analysis identified postoperative vision(notably eye removal),rumination levels,and psychological resilience(optimism)as major factors influencing PTSD in these patients(R^(2)=0.57,P<0.001).CONCLUSION:Young and middle-aged patients with open globe injuries have a high incidence of *** risk factors for early PTSD include primary enucleation,high levels of rumination,and low psychological resilience(optimism).Conversely,patients with good postoperative vision recovery,low rumination l

关键词： young and middle-aged open globe injuries post-traumatic stress disorder rumination psychological resilience

Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN T.ASGHAR z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： analytical solution Cattaneo-Christov heat and mass flux chemical reaction gyrotactic microorganism hybrid nanofluid O368 oscillating curved stretchable sheet

Phononic Resonant Relaxation in Magnetic Hysteresis of Single-Molecule Magnets

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Chinese Physics Letters 2025年第2期42卷 109-124页

作者： Lei Gu Jia luo Qiancheng luo Yuanqi zhai Yan-zhen zheng Guoping zhao College of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610068China Frontier Institute of Science and Technology(FIST) Xi’an Jiaotong UniversityXi’an 710054China Center for Magnetism and Spintronics Sichuan Normal UniversityChengdu 610068China

Lanthanide-based single-molecule magnets exhibit broad magnetic hysteresis,which manifests as slow magnetic relaxation in strong magnetic ***,the origin of the nontrivial hysteresis behaviors remains ***,we propose two influential mechanisms:activation of optical-phonon-mediated direct transitions within the ground-state doublet and the resonant Raman *** discoveries,coupled with the g-factor anisotropy,account for the observed hysteresis behaviors in the regimes of fast magnetic *** findings complement the recognized mechanisms used to interpret the magnetic hysteresis of single-molecule magnets.

关键词： process. hysteresis magnets

Spatio-temporal variations in air/ground freezing–thawing indices along the China–Nepal Highway during 1987–2017

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Journal of Mountain Science 2025年第2期22卷 521-536页

作者： zHANG Tianqi luo Tao zHANG Chonglei YU Wenbing PEI Wansheng Shaanxi Key Laboratory of Safety and Durability of Concrete Structures Xijing UniversityXi’an 710123China State Key Laboratory of Mountain Hazards and Engineering Resilience Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Institute of Future Civil Engineering Science and Technology Chongqing Jiaotong UniversityChongqing 400074China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Freezing–thawing indices serve as a comprehensive indicator of both the duration of the freezing/thawing periods and the degree of cold and heat in a given ***-depth analysis of the freezing-thawing indices not only enables the prediction of permafrost distribution and its dynamic changes,but also facilitates the assessment of damage risk to infrastructure under freeze-thaw *** this paper,the air/ground freezing–thawing indices from 1987 to 2017,based on daily temperature observations from meteorological stations along the China–Nepal Highway(CNH),were calculated,and their spatial and temporal variation patterns were *** results showed that:(1)Both mean annual air temperature and mean annual ground surface temperature along the CNH fluctuated upward,with climate tendency rates of 0.43 and 0.52.C·(10a)~(-1),respectively;(2)The number of days with negative air temperature and ground temperature showed fluctuated downward,with change rates of-8.6 and-8.3 d·(10a)~(-1),respectively;(3)The ranges of air freezing index,air thawing index,ground freezing index,and ground thawing index over the years were 157.05-458.88°C·d,2034.20-2560.73°C·d,108.78-396.83°C·d,and 3515.25-4288.67°C·d,*** climate tendency rates were-5.42,10.22,-6.79,and 12.14.C·d·a-1,respectively,showing a general warming trend;(4)The air freezing index,ground freezing index,and ground thawing index changed abruptly in 1999,2000,and 2002,respectively,evincing significant changes after *** research results can provide a basis for the risk assessment of freezing–thawing erosion and the prevention and control of permafrost engineering diseases along the CNH.

关键词： China–Nepal Transportation Corridor China–Nepal Highway Freezing–thawing indices Spatio–temporal change

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Distributed fiber optic sensing system for vibration monitoring of 3D printed bridges

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Optoelectronics Letters 2025年第1期21卷 28-34页

作者： zHAO Shuai zHOU Ran luo Mingming LIU Jianfei LIU Xiongfei zHOU Tao School of Electronic Information Engineering Hebei University of TechnologyTianjin 300401China Tianjin Key Laboratory of Electronic Materials and Devices Tianjin 300401China School of Civil Engineering and Transportation Hebei University of TechnologyTianjin 300401China Tianjin Jinhang Institute of Technical Physics Tianjin 300308China

The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities,including design,construction,and maintenance of bridges,tunnels,ports and other *** this paper,a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment,covering a vibration frequency from 5 Hz to 25 *** sensing fiber was arranged as an S type layout on the bridge to recognize the standing state,windblown disturbance,and walking ***,the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences,*** demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge,which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.

关键词： fiber bridges spinning

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Dissolved organic matter characteristics linked to bacterial community succession and nitrogen removal performance in woodchip bioreactors

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Journal of Environmental Sciences 2025年第2期148卷 625-636页

作者： Achen Wang Xiang Li Xuesong luo Guangwen He Daqing Huang Qiaoyun Huang Xue-Xian zhang Wenli Chen National Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070China Hubei Key Laboratory of Soil Environment and Pollution Remediation College of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070China School of Natural Sciences Massey University at AlbanyAuckland 0745New Zealand

Woodchip bioreactors are an eco-friendly technology for removing nitrogen(N)***,there needs to be more clarity regarding the dissolved organicmatter(DOM)characteristics and bacterial community succession mechanisms and their association with the N removal performance of *** laboratory woodchip bioreactors were continuously operated for 360 days under three influent N level treatments,and the results showed that the average removal rate of TN was 45.80 g N/(m3·day)when the influent N level was 100 mg N/L,which was better than 10 mg N/L and 50 mg N/*** succession of bacterial communities in response to influent N levels and DOM characteristics was an important driver of TN removal *** to high N levels enriched a copiotroph bacterial module(Module 1)detected by network analysis,including Phenylobacterium,Xanthobacteraceae,Burkholderiaceae,Pseudomonas,and Magnetospirillaceae,carrying N-cycle related genes for denitrification and ammonia assimilation by the rapid consumption of *** a process can increase carbon limitation to stimulate local organic carbon decomposition to enrich oligotrophswith fewer N-cycle potentials(Module 2).Together,this study reveals that the compositional change ofDOMand bacterial community succession are closely related to N removal performance,providing an ecological basis for developing techniques for N-rich effluent treatment.

关键词： Bacterial community succession Dissolved organic matter N removal performance Woodchip bioreactors

Optimizing local search-based partial MaxSAT solving via initial assignment prediction

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Science China(Information Sciences) 2025年第2期68卷 59-73页

作者： Chanjuan LIU Guangyuan LIU Chuan luo Shaowei CAI zhendong LEI Wenjie zHANG Yi CHU Guojing zHANG School of Computer Science and Technology Dalian University of Technology School of Software Beihang University Institute of Software Chinese Academy of Sciences School of Computer Science Peking University

Partial maximum satisfiability(PMS) is a significant generalization of Boolean satisfiability(SAT) and maximum satisfiability(MaxSAT), by introducing hard clauses and soft clauses. Compared with SAT and MaxSAT, the PMS problem has more real-world applications where both hard and soft constraints are involved. Local search is an effective incomplete method for solving PMS and is useful for important domains where good-quality solutions are desired within reasonable *** local search PMS solvers, the approach for initial assignment generation is crucial because its effectiveness significantly affects practical performance. In this study, we propose a novel initial assignment prediction approach, called InitPMS. When predicting an assignment for PMS, InitPMS considers the specific structure of PMS instances, i.e., distinguishing hard and soft clauses. Our experiments on extensive PMS instances from MaxSAT evaluations(MSEs) 2020 and 2021 show that InitPMS significantly boosts the performance of five state-of-the-art local search PMS solvers, demonstrating its generality. In addition,our results indicate that incorporating InitPMS could improve the performance of one of the best incomplete PMS solvers in MaxSAT Evaluation 2021, indicating that InitPMS might help advance the state of the art in PMS solving.

关键词： MaxSAT local search initial assignment incomplete method assignment prediction

Facile construction of heterogeneous dual-ionic poly(ionic liquid)s for efficient and mild conversion of CO_(2)into cyclic carbonates

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Journal of Environmental Sciences 2025年第3期149卷 177-187页

作者： Guanqun Xie Jiaxiang Qiu Huadeng Li Hongbin luo Shuo Li Yanbin zeng Ke zheng Xiaoxia Wang School of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Guangdong Provincial Engineering Technology Research Center of Key Material for High Performance Copper Clad LaminateDongguan University of TechnologyDongguan 523808China

In the context of peaking carbon dioxide emissions and carbon neutrality,development of feasible methods for converting CO_(2)into high value-added chemicals stands out as a hot *** this study,P[D+COO^(−)][Br^(−)][DBUH^(+)],a series of novel heterogeneous dual-ionic poly(ionic liquid)s(PILs)were synthesized readily from 2-(dimethylamino)ethyl methacrylate(DMAEMA),bromo-substituted aliphatic acids,organic bases and divinylbenzene(DVB).The structures,compositions and morphologies were characterized or determined by nuclear magnetic resonance(NMR),thermal gravimetric analysis(TGA),infrared spectroscopy(IR),scanning electron microscopes(SEM),and Brunauer-Emmett-Teller analysis(BET),*** of the P[D+COO^(−)][Br^(−)][DBUH^(+)]series as catalysts in converting CO_(2)into cyclic carbonates showed that P[D+COO^(−)][Br^(−)][DBUH^(+)]-2/1/0.6was able to catalyze epiclorohydrin-CO_(2)cycloaddition the most *** afforded chloropropylene carbonate(CPC)in 98.4%yield with≥99%selectivity in 24 hr under solvent-and additive-free conditions at atmospheric *** experiments showed that recycling of the catalyst 6 times only resulted in a slight decline in the catalytic *** addition,it could be used for the synthesis of a variety of differently substituted cyclic carbonates in good to excellent ***,key catalytic active sites were probed,and a reasonable mechanism was proposed *** summary,this work poses an efficient strategy for heterogenization of dual-ionic PILs and provides amild and environmentally benign approach to the fixation and utilization of carbon dioxide.

关键词： Dual-ionic poly(ionic liquid)s CO_(2)cycloaddition Epoxides Cyclic carbonates Heterogeneous catalysts