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Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan Shi qun yi Yao Liu yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Complete reconstruction Co-based complex Precatalysts Oxygen evolution reaction

Crystallization and dielectric properties of lead-free glass-ceramic composites with Gd_2O_3 addition

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Rare Metals 2012年第3期31卷 281-284页

作者： Zhou, yi Zhang, Qingmeng Luo, Jun Tang, qun du, Jun Advanced Electronic Materials Institute General Research Institute for Nonferrous Metals Beijing 100088 China

Lead-free glass-ceramic composites in barium sodium niobate silica system with Gd2O3 addition were synthesized through melt-casting fol-lowed by controlled crystallization technique. Crystallization and dielectric properties of the Gd2O3 adding glass-ceramic composites were investigated. With the increase in the concentration of Gd2O3, the glass transition temperature and the crystallization temperature of the pre-cursor glass shift towards the higher temperature. The crystallization behavior that occurred during the heat treatment procedure leads to the enhancement of dielectric constant. All the three compositions of glass-ceramic composites exhibit ferroelectricity when tested at room tem-perature. Both the values of the remanent polarization and coercive field are enhanced regularly with the gradual increase in the concentration of Gd2O3 additive under the same testing field.

关键词： Gd2O3 addition glass-ceramic composites crystallization dielectric properties ferroelectricity

Probing the ultrafast dynamics in nanomaterial complex systems by femtosecond transient absorption spectroscopy

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High Power Laser Science and Engineering 2016年第3期4卷 13-22页

作者： qun Zhang yi Luo Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical Physics and Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China

Over the past decade the integration of ultrafast spectroscopy with nanoscience has greatly propelled the development of nanoscience, as the key information gleaned from the mechanistic studies with the assistance of ultrafast spectroscopy enables a deeper understanding of the structure–function interplay and various interactions involved in the *** mini-review presents an overview of the recent advances achieved in our ultrafast spectroscopy laboratory that address the ultrafast dynamics and related mechanisms in several representative nanomaterial complex systems by means of femtosecond time-resolved transient absorption spectroscopy. We attempt to convey instructive, consistent information regarding the important processes, pathways, dynamics, and interactions involved in the nanomaterial complex systems,most of which exhibit excellent performance in photocatalysis.

关键词： nanomaterials time-resolved femtosecond pump-probe transient absorption spectroscopy ultrafast dynamics

Acellular porcine corneal matrix as a carrier scaffold for cultivating human corneal epithelial cells and fibroblasts in vitro

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International Journal of Ophthalmology(English edition) 2016年第1期9卷 1-8页

作者： ju zhang Can-Wei Zhang Li-qun du Xin-yi Wu Department of Ophthalmology Qilu Hospital of Shandong University Jinan 250012 Shandong Province China The Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of Education and Chinese Ministry of Health Qilu Hospital of Shandong University Jinan 250012 Shandong Province China

AIM：To investigate the feasibility of corneal anterior lamellar reconstruction with human corneal epithelial cells and fibroblasts,and an acellular porcine cornea matrix（APCM） in vitro.·METHODS：The scaffold was prepared from fresh porcine corneas which were treated with 0.5%sodium dodecyl sulfate（SDS）solution and the complete removal of corneal cells was confirmed by hematoxylin-eosin（HE）staining and 4’,6-diamidino-2-phenylindole（DAPI）*** corneal fibroblasts and epithelial cells were cultured with leaching liquid extracted from APCM,and then cell proliferative ability was evaluated by MTT *** construct a human corneal anterior lamellar replacement,corneal fibroblasts were injected into the APCM and cultured for 3d,followed by culturing corneal epithelial cells on the stroma construction surface for another *** corneal replacement was analyzed by HE staining,and immunofluorescence staining.·R ESULTS：Histological examination indicated that there were no cells in the APCM by HE staining,and DAPI staining did not detect any residual *** leaching liquid from APCM had little influence on the proliferation ability of human corneal fibroblasts and epithelial *** 10d,a continuous 3 to 5 layers of human corneal epithelial cells covering the surface of the APCM was observed,and the injected corneal fibroblasts distributed within the *** phenotype of the construction was similar to normal human corneas,with high expression of cytokeratin 12 in the epithelial cell layer and high expression of Vimentin in the stroma.·CONCLUSION：Corneal anterior lamellar replacement can be reconstructed in vitro by cultivating human corneal epithelial cells and fibroblasts with an acellular porcine cornea *** laid the foundation for the further transplantation in vitro.

关键词： corneal epithelial cells corneal keratocytes acellular porcine cornea matrix corneal tissue engineering limbal epithelial cells

Role of miR-124 in the regulation of retinoic acid-induced Neuro-2A cell differentiation

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Neural Regeneration Research 2020年第6期15卷 1133-1139页

作者： qun You Qiang Gong Yu-Qiao Han Rou Pi yi-Jie du Su-Zhen Dong Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghaiChina Department of Integrative Medicine Huashan HospitalFudan UniversityShanghaiChina Institutes of Integrative Medicine Fudan UniversityShanghaiChina

Retinoic acid can cause many types of cells,including mouse neuroblastoma Neuro-2 A cells,to differentiate into ***,it is still unknown whether microRNAs(miRNAs)play a role in this neuronal *** address this issue,real-time polymerase chain reaction assays were used to detect the expression of several differentiation-related miRNAs during the differentiation of retinoic acid-treated Neuro-2 A *** results revealed that miR-124 and miR-9 were upregulated,while miR-125 b was downregulated in retinoic acid-treated Neuro-2 A *** identify the miRNA that may play a key role,miR-124 expression was regulated by transfection of miRNA mimics or *** analysis results showed that inhibition of miR-124 expression reversed the effects of retinoic acid on neurite ***,miR-124 overexpression alone caused Neuro-2 A cells to differentiate into neurons,and its inhibitor could block this *** results suggest that miR-124 plays an important role in retinoic acid-induced differentiation of Neuro-2 A cells.

关键词： immunofluorescence MAP2 micro RNA mi R-124 Neuro-2A cells neurite outgrowth neuronal differentiation overexpression real-time PCR retinoic acid

Predicting the shrinkage of thermal insulation mortar by probabilistic neural networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 212-222页

作者： yi-qun DENG Pei-ming WANG Key Laboratory of Advanced Civil Engineering Materials Ministry of EducationTongji UniversityShanghai 200092China

This study explored the potential of using probabilistic neural networks (PNN) to predict shrinkage of thermal insulation *** results were obtained from the PNN model with the aid of Parzen non-parametric estimator of the probability density functions (PDF).Five variables,water-cementitious materials ratio,content of cement,fly ash,aggregate and plasticizer,were employed for input variables,while a category of 56-d shrinkage of mortar was used for the output variable.A total of 192 groups of experimental data from 64 mixtures designed using JMP7.0 software were collected,of which 120 groups of data were used for training the model and the other 72 groups of data for *** simulation results showed that the PNN model with an optimal smoothing parameter determined by the curves of the mean square error (MSE) and the number of unrecognized probability densities (UPDs) exhibited a promising capability of predicting shrinkage of mortar.

关键词： Mortar Shrinkage Probabilistic neural networks (PNN) Thermal insulation

How to improve machine learning models for lithofacies identification by practical and novel ensemble strategy and principles

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Petroleum Science 2023年第2期20卷 733-752页

作者： Shao-qun Dong Yan-Ming Sun Tao Xu Lian-Bo Zeng Xiang-yi du Xu Yang Yu Liang State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Science China University of PetroleumBeijing102249China College of Geoscience China University of PetroleumBeijing102249China

Typically, relationship between well logs and lithofacies is complex, which leads to low accuracy of lithofacies identification. Machine learning (ML) methods are often applied to identify lithofacies using logs labelled by rock cores. However, these methods have accuracy limits to some extent. To further improve their accuracies, practical and novel ensemble learning strategy and principles are proposed in this work, which allows geologists not familiar with ML to establish a good ML lithofacies identification model and help geologists familiar with ML further improve accuracy of lithofacies identification. The ensemble learning strategy combines ML methods as sub-classifiers to generate a comprehensive lithofacies identification model, which aims to reduce the variance errors in prediction. Each sub-classifier is trained by randomly sampled labelled data with random features. The novelty of this work lies in the ensemble principles making sub-classifiers just overfitting by algorithm parameter setting and sub-dataset sampling. The principles can help reduce the bias errors in the prediction. Two issues are discussed, videlicet (1) whether only a relatively simple single-classifier method can be as sub-classifiers and how to select proper ML methods as sub-classifiers;(2) whether different kinds of ML methods can be combined as sub-classifiers. If yes, how to determine a proper combination. In order to test the effectiveness of the ensemble strategy and principles for lithofacies identification, different kinds of machine learning algorithms are selected as sub-classifiers, including regular classifiers (LDA, NB, KNN, ID3 tree and CART), kernel method (SVM), and ensemble learning algorithms (RF, AdaBoost, XGBoost and LightGBM). In this work, the experiments used a published dataset of lithofacies from Daniudi gas field (DGF) in Ordes Basin, China. Based on a series of comparisons between ML algorithms and their corresponding ensemble models using the ensemble strat

关键词： Lithofacies identification Machine learning Ensemble learning strategy Ensemble principle Homogeneous ensemble Heterogeneous ensemble

On a BMAP/G/1 G-queue with Setup Times and Multiple Vacations

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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 625-638页

作者： yi PENG Xiang-qun YANG School of Mathematical Science and Computing Technology Central South University Changsha 410075 Hunan China College of Mathematics and Computer Science Hunan Normal University Changsha 410081 China

In this paper, we consider a BMAP/G/1 G-queue with setup times and multiple vacations. Arrivals of positive customers and negative customers follow a batch Markovian arrival process （BMAP） and Markovian arrival process （MAP） respectively. The arrival of a negative customer removes all the customers in the system when the server is working. The server leaves for a vacation as soon as the system empties and is allowed to take repeated （multiple） vacations. By using the supplementary variables method and the censoring technique, we obtain the queue length distributions. We also obtain the mean of the busy period based on the renewal theory.

关键词： G-queues batch Markovian arrival process (BMAP) setup times multiple vacations censoring technique Markov chains

Predictors for partial suppression of spermatogenesis of hormonal male contraception

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Asian Journal of Andrology 2008年第5期10卷 723-730页

作者： Jing-Wen Li yi-qun Gu peking Union Medical College Postgraduate School Beijing 100730 China National Research Institute for Family Planning Beijing 100081 China

Aim： To analyze factors influencing the efficacy of hormonal suppression of spermatogenesis for male contraception. Methods： A nested case-control study was conducted, involving 43 subjects, who did not achieve azoospermia or severe oligozoospermia when given monthly injections of 500 mg testosterone undecanoate （TU）, defined as partial suppressors compared with 855 subjects who had suppressed spermatogenesis （complete suppressors）. Sperm density, serum testosterone, luteinizing hormone （LH） and follicle stimulating hormone （FSH） concentrations at the baseline and the suppression phase were compared between partial and complete suppressors. Polymorphisms of androgen receptor （AR） and three single nucleotide variants and their haplotypes of FSH receptor （FSHR） genes determined by polymerase chain reaction （PCR） and DNA sequencing technique were compared between 29 partial and 34 complete suppressors. Results： Baseline serum LH level was higher and serum LH as well as FSH level during the suppression phase was less suppressed in partial suppressors. Additionally, in a logistic regression analysis larger testis volume, higher serum FSH concentrations alone, or interaction of serum LH, FSH, testosterone and sperm concentrations were associated with degree of suppression. The distribution of polymorphisms of AR or FSH receptor genes did not differ between partial and complete suppressors. In cases with incomplete FSH suppression （FSH 〉 0.2 IU/L）, the chances of reaching azoospermia were 1.5 times higher in the subjects with more than 22 CAG triplet repeats. Conclusion： Partial suppression of spermatogenesis induced by 500 mg TU monthly injections is weakly influenced by hormonal and clinical features but not polymorphism in AR and FSHR genes.

关键词： male contraception genetic polymorphism androgen receptor CAG repeats follicle stimulating hormone receptor single nucleotide polymorphism sperm concentration