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Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-Sheng Nong Hao-Fan Qian Ying-Chun Chen Pu-Sheng Wang Liu-zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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Multi-source and multi-temporal remote sensing image classification for flood disaster monitoring

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Global Geology 2025年

作者： LI zhu JIA Zhenyang DONG Jing LIU Zhenghong College of Earth Sciences Jilin University Dandong No.2 High School

Flood disasters can have a serious impact on people's production and lives, and can cause huge ***-sourceremotesensingdata,thisstudyestablished decision tree classification rules through multi-source and multi-temporal feature fusion, classified ground objects before the disaster and extracted flood information in the disaster area based on optical images during the disaster, so as to achieve rapid acquisition of the disaster situation of each disaster bearing *** the case of Qianliang Lake, which suffered from flooding in 2020, the results show that decision tree classification algorithms based on multi-temporal features can effectively integrate multi-temporal and multispectral information to overcome the shortcomings of single-temporal image classification and achieve ground-truth object classification.

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Steel surface defect detection based on lightweight YOLOv7

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Optoelectronics Letters 2025年

作者： Shi Tao Wu Rongxin zhu Wenxu Ma Qingliang School of Electrical Engineering and Automation， Tianjin University of Technology North China University of Science and Technology， College of Electrical Engineering Guangzhou Institute of Measurement and Testing Technology

Aiming at the problems of low detection efficiency and difficult positioning of traditional steel surface defect detection methods， a lightweight steel surface defect detection model based on YOLOv7 is proposed. First， a CSS Block module is proposed， which uses more lightweight operations to obtain redundant information in the feature map， reduces the amount of computation， and effectively improves the detection speed. Secondly， the improved SPPCSPC structure is adopted to ensure that the model can also pay attention to the defect location information while predicting the defect category information， obtain richer defect features. In addition， the convolution operation in the original model is simplified， which significantly reduces the size of the model and helps to improve the detection speed. Finally， using EIOU Loss to focus on high-quality Anchors， speed up convergence and improve positioning accuracy. Experiments were carried out on the NEU-DET steel surface defect dataset. Compared with the original YOLOv7 model， the number of parameters of this model was reduced by 40%， the FPS reached 112， and the average accuracy reached 79.1%.， the detection accuracy and speed have been improved， which can meet the needs of steel surface defect detection.

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Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin

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Journal of Geographical Sciences 2025年第1期35卷 88-111页

作者： YANG Peng SUN Kaiya zhu Yanchao XIA Jun HUANG Heqing SONG Jingxia SHI Xiaorui LU Xixi Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information Engineering China University of Geosciences Department of Geography National University of Singapore State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Wetlands play a critical role in the global environment. The Middle Yangtze River Basin(MYRB), known for its abundant wetland resources, has experienced notable changes resulting from the complex interplay of environmental factors. Therefore, we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to *** the random forest(RF) regression algorithm and patch-generated land-use simulation(PLUS) model, we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP) framework from 2035 to 2095. The main findings are as follows:(1) The RF algorithm was optimal for land-use and land-cover(LULC) classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings. However, the forested area exhibited an increase and decrease of 3.9% and 1.2% under the SSP1-2.6 and SSP5-8.5 scenarios, respectively, whereas farmland exhibited a diminishing trend.(2) Wetlands were primarily concentrated in the central and eastern MYRB, with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020. Notably,wetland coverage revealed significantly high level, significant changes, frequent but relatively minor changes under the SSP1-2.6, SSP2-4.5, and SSP 5-8.5 scenarios, respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities, indicating a clear degradation in habitat quality across different scenarios. In conclusion, we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds.

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Asymmetric interfacial engineering regulated charge distribution on Ru/Ni-N-C sites for efficient hydrogen evolution reaction in alkaline and seawater electrolytes

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Science China Chemistry 2025年

作者： Rui Yu Xi Cao Chengyang zhu Qingqing Chen Ziyi Yan Binbin Jiang Junjie Mao Xianwen Wei Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes College of Chemistry and Materials ScienceAnhui Normal University Anhui Provincial Key Laboratory of Advanced Catalysis and Energy Materials School of Chemistry and Chemical Engineering Anqing Normal University School of Chemistry and Chemical Engineering Anhui University of Technology

Developing highly efficient and cost-effective electrocatalysts for hydrogen evolution reaction（HER） is grandly challenging in alkaline and alkaline seawater electrolytes. Herein, the asymmetric interfacial active sites with Ru nanoparticles and Ni single atoms in Ru/Ni-N-C were designed through a solvothermal-pyrolysis process. Constructing highly asymmetric interfacial active sites with a strong electron delocalization effect significantly improves HER kinetics. As expected, Ru/Ni-N-C requires low overpotentials with around 20 mV at 10 mA cm-2and robust durability over 48 h in alkaline and alkaline seawater *** at 200 mA cm-2, the overpotentials are close to 100 mV in both above electrolytes for Ru/Ni-N-C. Density function theory calculation results suggest that the asymmetric interface between Ru nanoparticle and Ni-N-C could accelerate the dissociation of water molecules and modulate the hydrogen species, consequently improving the HER performances. This work opens a unique approach for constructing advanced materials for energy conversion.

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Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： Song Jiang Congwen zhu Ning Jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

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Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 46-51页

作者： Yiying zhu Hesong Wang Anzhi Zhang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Forestry and Landscape Architecture Xinjiang Agricultural UniversityUrumqiChina

Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of *** the same time,detailed accounts of disturbances and forest responses are not yet well quantified in *** study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast *** approach allowed us to detect forest disturbance and quantify the resilience after *** showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by ***,95%of forests had robust resilience and could recover from disturbance within a few *** resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance *** summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two *** authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in *** findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing.

关键词： Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method Disturbance Resilience

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Specific staining and precise killing of cancer cells through fusion of pharmaceutical chemistry and π-bridge effect design philosophy

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Science China Chemistry 2025年

作者： Qiong Liu Qiyun Deng Changxu zhu Kongqi Chen Lidan Chen Zhaohui Sun Ben Zhong Tang Zhiming Wang AIE Institute Center for Aggregation-Induced Emission State Key Laboratory of Luminescent Materials and Devices Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province South China University of Technology Department of Laboratory Medicine General Hospital of Southern Theater Command School of Life Sciences The Chinese University of Hong Kong Shenzhen Institute of Aggregate Science and Technology School of Science and Engineering The Chinese University of Hong Kong HKUST-Shenzhen Research Institute

The development of an advanced phototheranostic platform that combines imaging and therapy in a single agent is an appealing yet challenging *** this study,we successfully constructed three novel fluorescent probes by leveraging pharmaceutical chemistry and the design philosophy of theπ-bridge *** a systematic comparative analysis of their fluorescence properties,water solubility,molecular conformation,and electrostatic potential,we revealed the fundamental principles governing the optical behavior and biological selectivity of these ***,the probe TPhIQ-CNTh demonstrated extended fluorescence in the near-infrared region,a significant aggregation-induced emission (AIE) effect,and the ability to distinguish tumor cells from normal ***,it efficiently generated reactive oxygen species (ROS) and specifically labeled lipid droplets,enabling the precise staining and killing of cancer *** study presents a practical strategy for designing precise tumor treatments that integrate efficient imaging-guided photodynamic therapy (PDT) by harnessing the unique properties of AIE materials.

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Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3287-3301页

作者： Ziwei Fan Mengxian Jia Jian Zhou Zhoule zhu Yumin Wu Xiaowu Lin Yiming Qian Jiashu Lian Xin Hua Jianhong Dong Zheyu Fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu zhu Ying Wang Zhihui Huang Honglin Teng Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Neurology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina

The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord *** of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be *** possesses an anti-inflammatory biological ***,its roles and the underlying molecular mechanisms in spinal cord injury remain *** this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in *** promoted M2 polarization through inactivating the cGAS/STING/NF-κB ***,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord ***,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal *** together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype.

关键词： cGAS/STING functional recovery microglia neuroinflammation neuroprotection nuclear factor-κB polarization spinal cord injury tryptanthrin

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Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

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