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Co@C-N as an electronic mediator anchored with Cu2O nanoparticles enables efficient photoreduction of CO2 to CO with nearly 100% selectivity

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Science China Chemistry 2025年

作者： Xingbin pan Xiuzheng Deng Jingshan Fan Jiangchuan Liu Changhai Liu Zhongyu Li qian Liang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology CNPC-CZU Innovation Alliance School of Petrochemical Engineering Changzhou University School of Materials Science & Engineering Changzhou University

Solar-driven CO2conversion into value-added chemical provides an attractive strategy for sustainable development. However,the enhanced CO2photoreduction performance with target product selectivity remains a major challenge. Here, we develop a novel strategy involving Cu2O nanoparticles in situ grown on the surface of ZIF-67-derived Co@C-N nanocages （CC） to create abundant active sites and appropriate heterointerfaces. A remarkable CO selectivity of 95.7%with a yield of 117.39μmol g-1h-1and an apparent quantum efficiency as high as 1.88%at 420 nm was obtained over CC-60 catalyst in pure water, which was 87.6times higher than that of pure Cu2O. Theoretical calculations and experiments indicated that Co@C-N nanocages as charge mediator not only rapidly trap photogenerated electrons to promote charge separation efficiency, but also regulate the d-band center of Cu atoms to move to the Fermi energy level, thereby optimizing the reaction kinetics to facilitate the highly selective conversion of the key intermediate *CO desorption to CO.

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Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年

作者： gang Huang qian Dang Cong-cong Su Jing Zhao Chi Zhang Guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern University School of Materials Science and Engineering Shenyang University of Technology

The grain size of TiAl alloy castings prepared by traditional casting process is coarse, thus showing poor mechanical properties. In this study, a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced. This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings, employing both experimental approaches and ProCast simulation methodologies. The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains. Under the condition of pouring temperature of 1,600 °C, rotation speed of 800 r·min-1and pouring time of 6 s, the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa, and the tensile strength at 800 °C reaches 705 MPa, which is significantly higher than that of traditional as-cast Ti-Al alloy.

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Insufficient MIRO1 contributes to declined oocyte quality during reproductive aging

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Science China Life Sciences 2025年

作者： Zhen-Nan pan Hao-Lin Zhang Kun-Huan Zhang Jia-qian Ju Jing-Cai Liu Shao-Chen Sun College of Animal Science and Technology Nanjing Agricultural University Reproductive Medicine Centre The Affiliated Yantai Yuhuangding Hospital of Qingdao University

Mitochondrial Rho-GTPase 1 (MIRO1) is an outer mitochondrial membrane protein which regulates mitochondrial transport and mitophagy in mitosis. In present study, we reported the crucial roles of MIRO1 in mammalian oocyte meiosis and its potential relationship with aging. We found that MIRO1 expressed in mouse and porcine oocytes, and its expression decreased in aged mice. MIRO1 deficiency caused the failure of meiotic resumption and polar body extrusion in both mouse and porcine oocytes, which could be rescued by exogenous MIRO1supplementation. Mass spectrometry data indicated that MIRO1 associated with several cytoskeleton and cell cycle-related proteins, and MIRO1 regulated motor protein Dynein for microtubule-organizing centers (MTOCs) dynamics at germinal vesicle (GV) stage, which determined meiotic resumption. Furthermore, we found that MIRO1 regulated Aurora A and kinesin family member 11 (KIF11) for meiotic spindle assembly in oocytes. Besides, MIRO1 associated with several mitochondria-related proteins dynamic-related protein 1 (DRP1),Parkin and lysosomal-associated membrane protein 2 (LAMP2) for mitochondrial dynamics and mitophagy during oocyte meiosis. Taken together, our results suggested that MIRO1 played pivotal roles in meiotic resumption, spindle assembly and mitochondrial function in mouse and porcine oocytes, and its insufficiency might contribute to the oocyte maturation defects during aging.

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大功率电源网侧谐波电流抑制技术研究

舰船电子对抗 2017年第4期50卷 84-86,94页

作者：刘刚孙前刚潘李云中国船舶重工集团公司第七二三研究所江苏扬州225001

分析了大功率电源工作时谐波电流产生的机理,介绍了常用于网侧谐波电流抑制的2种方法,重点针对三相全桥电压源高频脉宽调制(PWM)整流器的控制策略和电抗器结构进行了研究,试验表明基于LCL结构的三相电压源整流器能够取得比单电感更优的... 详细信息

分析了大功率电源工作时谐波电流产生的机理,介绍了常用于网侧谐波电流抑制的2种方法,重点针对三相全桥电压源高频脉宽调制(PWM)整流器的控制策略和电抗器结构进行了研究,试验表明基于LCL结构的三相电压源整流器能够取得比单电感更优的谐波电流抑制效果。

关键词：电压源 LCL结构谐波

维普期刊数据库

Summary study of data-driven photometric stereo methods

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Virtual Reality & Intelligent Hardware 2020年第3期2卷 213-221页

作者： qian ZHENG Boxin SHI gang pan School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore National Engineering Laboratory for Video Technology Department of CSPeking UniversityBeijing 100871China State Key Lab of CAD&CG College of Computer Science and TechnologyZhejiang UniversityHangzhou 310058China

Background A photometric stereo method aims to recover the surface normal of a 3D object observed under varying light *** is an ill-defined problem because the general reflectance properties of the surface are *** This paper reviews existing data-driven methods,with a focus on their technical insights into the photometric stereo *** divide these methods into two categories,per-pixel and all-pixel,according to how they process an *** discuss the differences and relationships between these methods from the perspective of inputs,networks,and data,which are key factors in designing a deep learning *** We demonstrate the performance of the models using a popular benchmark *** Data-driven photometric stereo methods have shown that they possess a superior performance advantage over traditional ***,these methods suffer from various limitations,such as limited generalization ***,this study suggests directions for future research.

关键词： Photometric stereo Data-driven methods Non-Lambertian reflectance

Advances and challenges in developing cocatalysts for photocatalytic conversion of carbon dioxide to fuels

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Nano Research 2022年第12期15卷 10090-10109页

作者： qian Wang Zhenhua pan Graduate School of Engineering Nagoya UniversityFuro-choChikusa-kuNagoya464-8603Japan Institute for Advanced Research Nagoya UniversityFuro-choChikusa-kuNagoya464-8601Japan Department of Applied Chemistry Faculty of Science and TechnologyChuo University1-13-27 KasugaBunkyoTokyo112-8551Japan

The global adoption of efficient sustainable energy sources is a crucial step toward meeting energy demands while achieving carbon emission reduction *** energy has become a clean and cost-competitive alternative to traditional fossil fuels,but the intermittent nature of sunlight results in challenges associated with energy storage and *** carbon dioxide reduction intends to mimic natural photosynthesis for utilizing sunlight to chemically convert water and CO_(2) into *** this process,the solar energy is captured and stored in fuels,so-called solar fuels,for widespread on-demand *** solar fuel production systems are multi-component,comprising light-harvesting(photosensitizer)and catalytic(cocatalyst)*** are indispensable for photocatalytic CO_(2) reduction systems,which promote charge carrier separation and transport,reduce the reaction activation energy,and alter the reaction route,thereby enhancing the activity and selectivity of the photocatalytic *** review presents a comprehensive summary of the recent advancements in cocatalysts for photocatalytic CO_(2) reduction reaction(CO_(2)RR),with the purpose of providing new insights and guidance to the field with regard to research directions and best *** summarize how various cocatalysts including inorganic nanoparticles,metal complexes,enzymes,and bacteria can be combined with semiconductor photosensitizer for light-driven photocatalytic CO_(2)***-by-side comparisons reveal the strengths and limitations of each kind of cocatalysts and how lessons extracted from studying natural photosynthetic systems can be applied to investigations of artificial photosynthesis,presenting an outlook discussing possible future concepts for a more effective photocatalytic CO_(2) reduction process.

关键词： photocatalysis cocatalyst carbon dioxide reduction artificial photosynthesis solar fuel production

Passivation process of X80 pipeline steel in bicarbonate solutions

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 178-184页

作者： Jian-long Zhou Xiao-gang Li Cui-wei Du Ying pan Tao Li qian Liu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Wuhan Research Institute of Materials Protection wtthan 430030 China School of Materials ＆ Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 China

The passivation process of X80 pipeline steel in bicarbonate solutions was investigated using potentiodynamic, dynamic electro-chemical impedance spectroscopy （DEIS）, and Mott-Schottky measurements. The results show that the shape of polarization curves changes with concentration. The critical ＇passive＇ concentration is 0.009 mol/L for X80 pipeline steel in bicarbonate solutions. No anodic current peak exists in solutions when the concentration is lower than 0.009 mol/L, whereas there are one and two anodic current peaks when the concentration ranges from 0.009 to 0.05 mol/L and is higher than 0.1 mol/L, respectively. DEIS measurements show that there exist active dissolution range, transition range, pre-passive range, passive layer formation range, passive range, and trans-passive range for X80 pipeline steel in the 0.1 mol/L solutions. The results of DEIS measurements are in complete agreement with the potentiodynamic diagram. An equivalent circuit containing three sub-layers is used to explain the Nyquist plots in the passive range. Analyses are well made for explaining the corresponding fitted capacitance and impedance. The Mott-Schottky plots show that the passive film of X80 pipeline steel is an n-type semiconductor, and capacitance measurements are in good accordance with the results of DEIS experiment.

关键词： pipeline steel bicarbonate solutions passivation potentiodynamic polarization electrochemical impedance spectroscopy

维普期刊数据库

3D Rigid-Plastic Finite Element Analysis for Skew Rolling Process of the Stepped Part

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Journal of Materials Science & Technology 2003年第Z1期19卷 38-40页

作者： gang FANG pan ZENG Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Based on rigid-plastic finite element method, a skew rolling process of stepped part is simulated. Considering nodesaving and effective remeshing, the tetrahedron solid elements are used to discrete workpiece. The workpiece material adopts rigid-plastic model, where the flow stress is function of effective strain, effective strain rate and *** thermomechanical coupling is considered in the simulation. To model the spinning workpiece undergoing plastic deformation, a novel solution is presented and applied in this paper. The stress state in the workpiece and forming characteristic of skew rolling are analyzed. The forming load, including roller torque and forces in three directions are predicted. The above analyses are helpful to understanding of forming mechanisms and improving of process and die design.

关键词： FEM, Skew rolling, Stepped part, Spinning part, Fracture

Monitoring and diagnosis of complex production process based on free energy of Gaussian–Bernoulli restricted Boltzmann machine

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Journal of Iron and Steel Research International 2023年第5期30卷 971-984页

作者： qian-qian Dong Qing-ting qian Min Li gang Xu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China

Online monitoring and diagnosis of production processes face great challenges due to the nonlinearity and multivariate of complex industrial *** process monitoring methods employ kernel function or multilayer neural networks to solve the nonlinear mapping problem of ***,the above methods increase the model complexity and are not interpretable,leading to difficulties in subsequent fault recognition/diagnosis/location.A process monitoring and diagnosis method based on the free energy of Gaussian-Bernoulli restricted Boltzmann machine(GBRBM-FE)was ***,a GBRBM network was established to make the probability distribution of the reconstructed data as close as possible to the probability distribution of the raw *** this basis,the weights and biases in GBRBM network were used to construct F statistics,which represents the free energy of the *** smaller the energy of the sample is,the more normal the sample ***,F statistics can be used to monitor the production *** diagnose fault variables,the F statistic for each sample was decomposed to obtain the Fv statistic for each *** analyzing the deviation degree between the corresponding variables of abnormal samples and normal samples,the cause of process abnormalities can be accurately *** application of converter steelmaking process demonstrates that the proposed method outperforms the traditional methods,in terms of fault monitoring and diagnosis performance.

关键词： Process monitoring Fault diagnosis Gaussian–Bernoulli restricted Boltzmann machine Energy function Free energy Converter steelmaking production process