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The renaissance of oxo synthesis: heterogeneous Rh-catalyzed hydroformylation

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Science China Chemistry 2025年

作者： Tao Yan zhi cao State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences National Energy Center for Coal to Clean Fuels Synfuels China Technology Co. Ltd.

Hydroformylation could convert olefins and syngas （mixture of H2and CO） into aldehydes with a great atomic *** transformation serves as one of the most prominent processes in modern chemical industry, as it provides over 10million tons of aldehydes as feedstock for our daily essential products such as plasticizers, paints, solvents, and pharmaceuticals. This process generally requires efficient yet robust catalyst to realize decent efficacy. Compared with metals such as Co, Ru, and Pd, rhodium （Rh）-based catalysts stand out due to its superior activity even under mild reaction conditions, and dominate over 70%of global hydroformylation processes.

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang zhi-Li Zuo han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report

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World Journal of Clinical Cases 2025年第2期13卷 50-58页

作者： Xiu-Ying Chen Fa Shen Chang Cheng Yu-han Wang Wen-Chao Cheng De-zhi Yuan Wen Huang Department of Neurology Chongqing Emergency Medical CenterChongqing University Central HospitalChongqing 400000China Department of Neurology Xinqiao HospitalThe Army Medical University(Third Military Medical University)Chongqing 400000China

BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic *** cerebral fat embolism(CFE)as a complication is rare,it carries serious health *** SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling *** the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided *** physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon *** clinical diagnosis was acute cerebral embolism following facial fat filling *** included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb *** patient showed a significant improvement in symptoms after 2 weeks of *** recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of *** Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial *** prevent these complications,plastic surgeons should enhance their professional knowledge and skills.

关键词： Cerebral fat embolism Mechanical thrombectomy Thrombolysis Steroid therapy Symptomatic treatment Case report

A high-capacity cathode for rechargeable K-metal battery based on reversible superoxide-peroxide conversion

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National Science Review 2021年第10期8卷 33-41页

作者： Yu Qiao han Deng zhi Chang Xin cao Huijun Yang Haoshen Zhou Energy Technology Research Institute National Institute of Advanced Industrial Science and Technology (AIST) Center of Energy Storage Materials &Technology College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsNational Laboratory of Solid State Microstructures and Collaborative Innovation Center of Advanced MicrostructuresNanjing University

As a promising low-cost energy storage device, the development of a rechargeable potassium-ion battery(KIB) is severely hindered by the limited capacity of cathode candidates. Regarded as an attractive capacity-boosting strategy, triggering the O-related anionic redox activity has not been achieved within a sealed KIB system. Herein, in contrast to the typical gaseous open K-Obattery(O/KOredox), we originally realize the reversible superoxide/peroxide(KO/KO) interconversion on a KO-based cathode. Controlled within a sealed cell environment, the irreversible Oevolution and electrolyte decomposition(induced by superoxide anion(O~-) formation) are effectively restrained. Rationally controlling the reversible depth-of-charge at 300 m Ah/g(based on the mass of KO), no obvious cell degradation can be observed during 900 cycles. Moreover, benefitting from electrolyte modification, the KO-based cathode is coupled with a limited amount of K-metal anode(merely 2.5 times excess),harvesting a K-metal full-cell with high energy efficiency(～90%) and long-term cycling stability(over 300 cycles).

关键词： electrochemistry rechargeable battery beyond Li-ion battery long-term cycle life high capacity cathode

Non-capacity transport of non-uniform bed load sediment in alluvial rivers

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Journal of Mountain Science 2016年第3期13卷 377-396页

作者： cao zhi-xian HU Peng PENDER Gareth LIU Huai-han State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China Institute for Infrastructure and Environment Heriot-Watt University Edinburgh EH14 4AS UK Ocean College Zhejiang University Hangzhou 316021 China Changjiang Waterway Bureau Wuhan 430010 China

Rivers often witness non-uniform bed load sedim ent transport. For a long tim e, non-uniform bed load transport has been assum ed to be at capacity regime determined exclusively by local flow. Yet whether the capacity assumption for non-uniform bed load transport is justified remains poorly understood. Here, the relative time scale of non-uniform bed load transport is evaluated and non-capacity and capacity models are compared for both aggradation and degradation cases with observed data. As characterized by its relative time scale, the adaptation of non-uniform bed load to capacity regime should be fulfilled quickly. However, changes in the flow and sedim ent inputs from upstream or tributaries hinder the adaptation. Also, the adaptation to capacity regime is size dependent, the finer the sediment size the slower the adaptation is, and vice versa. It is shown that the capacity model may entail considerable errors compared to the non-capacity model. For modelling of non-uniform bed load, non-capacity modelling is recommended, in which the temporal and spatial scales required for adaptation are explicitly appreciated.

关键词： Fluvial process Sediment transport Bed deformation Non-uniform bed load Capacity transport

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Numerical modelling of riverbed grain size stratigraphic evolution

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International Journal of Sediment Research 2014年第3期29卷 329-343页

作者： Peng HU zhi-xian cao Gareth PENDER Huai-han LIU Ocean College Zhejiang University State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Institute for Infrastructure and Environment Heriot-Watt University Institute for Infrastructure and Environment Heriot-Watt University State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Yangtze Waterway Planning Design and Research Institute

For several decades,quantification of riverbed grain size stratigraphic evolution has been based upon the active layer formulation(ALF),which unfortunately involves considerable *** it is the sediment exchange across the bed surface that directly affects the riverbed stratigraphy,it has been assumed in the ALF that the sediment fraction at the lower interface of the active layer is a linear function of the sediment fraction in the *** it is proposed that the sediment fraction of the sediment exchange flux is used directly in estimating the sediment fraction at the lower surface of the active *** with the size-specific mass conservation for riverbed sediment,the modified approach is referred to as the surface-based formulation(SBF).When incorporated into a coupled non-capacity modelling framework for fluvial processes,the SBF leads to results that agree as well or better than those using ALF with laboratory and field *** is illustrated for typical cases featuring bed aggradation and degradation due to graded bed-load sediment *** experiments on graded sediment transport by unsteady flows are warranted for further testing the modified formulation.

关键词： Bedload Riverbed grain size stratigraphy Active layer formulation Surface-based formulation Numerical modelling

Synthesis,Structure and Properties of Layered Phosphide Nitrides AkTh_(2)Mn_(4)P_(4)N_(2)(Ak=Rb,Cs)

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Chinese Journal of Chemistry 2021年第10期39卷 2873-2880页

作者： Bai-Zhuo Li Si-Qi Wu zhi-Cheng Wang cao Wang Guang-han cao Department of Physics Zhejiang Province Key Laboratory of Quantum Technology and DevicesInterdisciplinary Center for Quantum Informationand State Key Lab of Silicon MaterialsZhejiang UniversityHangzhouZhejiang310027 China School of Physics&Optoelectronic Engineering Shandong University of TechnologyZiboShandong 255000China Collaborative Innovation Centre of Advanced Microstructures Nanjing UniversityNanjingJiangsu210093 China

Main observation and conclusion We report the design,synthesis,structure,and properties of two complex layered phosphide nitrides,AkTh_(2)Mn_(4)P_(4)N_(2)(Ak=Rb,Cs),which contain anti-fluorite-type[Mn_(2)P_(2)]bilayers separated by fluorite-type[Th_(2)N_(2)]layers as a result of the intergrowth between AkMn2P2 and *** new compounds are featured with an intrinsic hole doping associated with the interlayer charge transfer and a built-in chemical pressure from the[Th_(2)N_(2)]layers,both of which are reflected by the changes in the lattice and the atomic position of *** measurements of magnetic susceptibility,electrical resistivity,and specific heat indicate existence of local moments as well as itinerant electrons in relation with d-p *** expected dominant antiferromagnetic interactions with enhanced d-p hybridizations were demonstrated by the first-principles calculations only when additional Coulomb repulsions are *** density of states at the Fermi level derived from the specific-heat analysis are 3.5 and 7.5 times of the calculated ones for Ak=Rb and Cs,respectively,suggesting strong electron correlations in the title compounds.

关键词： Intercalations Synthetic methods Physical properties Phosphide nitrides Electronic structure

Observation of ballistic-diffusive thermal transport in GaN transistors using thermoreflectance thermal imaging

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Rare Metals 2024年第1期43卷 389-394页

作者： zhi-Ke Liu Yang Shen han-Ling Li Bing-Yang cao Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

To develop effective thermal management strategies for gallium-nitride (GaN) transistors, it is essential to accurately predict the device junction temperature. Since the width of the heat generation in the devices is comparable to phonon mean free paths (MFPs) of GaN, phonon ballistic transport exists and can significantly affect the heat transport process.

关键词： temperature. transistors GaN

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A wave-shaped electrode flexible sensor capable of sensitively responding to wrinkle excitation for a multifunctional human-computer interaction system

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Nano Research 2024年第5期17卷 4454-4461页

作者： Yongyang Chen zhiyi Wu Chengcheng han zhi cao Yiran Hu Ping Zhao Yuanyu Wang College of Materials and Metallurgy Guizhou UniversityGuizhou 550025China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China Geological Brigade 105 Bureau of Geology and Mineral Exploration and Development of Guizhou ProvinceGuiyang 550018China

Human-machine interactions(HMIs)have advanced rapidly in recent decades in the fields of healthcare,work,and ***,people with disabilities and other mobility problems do not have corresponding high-tech aids for them to enjoy the convenience of *** this paper,we propose a sensor with a wave-shaped(corrugated)electrode embedded in a friction layer,which exhibits high sensitivity to skin fold excitation and enormous potential in *** to the wave-shaped electrode design,it has no built-in cavities,and its small size allows it to flexibly cope with folds at different *** specifying the carbon nanotube hybrid silicone film as the electrode layer material and silicone film as the friction layer,good electrical output performance,tensile properties,and biocompatibility can be ***,the sensor is tested on various joints and skin folds of the human body,the output signals of which can be distinguished between normal physiological behavior and test *** on this sensor,we designed a medical alarm system,a robotic arm assistive system,and a cell phone application control system for the disabled to help them in the fields of healthcare,work,and *** conclusion,our research presents a feasible technology to enhance HMIs and makes a valuable contribution to the development of high-tech aids for the disabled.

关键词： flexible sensors multifunctionality wrinkle excitation triboelectric nanogenerator human-machine interaction