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Chinese Chemical Letters 2020年第2期31卷 525-529页

作者： Siqi Fan Yue Wang Zhuoshi Li zhuang zeng Shaoxia Guo Shouying Huang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Centre of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Surface chemical properties of supports have an important influence on active sites and their catalytic behavio r.Here,we fabricated a series of cobalt-based catalysts supported by carbon layer-coated ordered mesoporous silica(OMS) composites for higher alcohol synthesis(HAS).The carbon layers were derived from different sources and uniformly coated on the porous surface of OMS.Combined with the characterization results of carbonized catalysts,it is demonstrated that the carbon layer-coated supports significantly enhanced the metal dispersion and increased the ratio of Co2+ to Co0 sites,which further increased the CO conversion and alcohols selectivity.Moreover,it is found that the catalytic activity changed in line with the amount of defects and surface oxygenic groups of carbon layers,which re sulted from the different carbon sources.The highest space time yield of C2+OH was 27.5 mmol gcat-1h-1)obtained by the catalyst coated with glucose-derived carbon layer.But the carbon source is not the key factor influencing the distribution of Co-Co2+ dual sites and shows little effect on selectivity in HAS.These results may guide for further design of carbon supported catalysts.

关键词： Syngas Higher alcohols Cobalt-based catalysts Carbon layer-coated support Carbon source

CO/CO_(2)加氢制低碳醇改性费托合成催化剂研究进展

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化工进展 2024年第6期43卷 3061-3079页

作者：曾壮李柯志苑志伟杜金涛李卓师王悦中国石化催化剂有限公司工程技术研究院北京101111 天津大学化工学院教育部绿色合成与转化重点实验室天津300350

一氧化碳/二氧化碳(CO/CO_(2))加氢制低碳醇(C2+OH)是碳一化学的重要组成部分,是将煤、天然气、生物质、CO_(2)等非石油资源转化为液体燃料和高附加值化学品的重要途径。该过程具有工艺路线短、原子经济性高、操作可行性强等优点,是颇... 详细信息

一氧化碳/二氧化碳(CO/CO_(2))加氢制低碳醇(C2+OH)是碳一化学的重要组成部分,是将煤、天然气、生物质、CO_(2)等非石油资源转化为液体燃料和高附加值化学品的重要途径。该过程具有工艺路线短、原子经济性高、操作可行性强等优点,是颇具前景的合成路线。改性的费托合成催化剂是该体系最具潜力的催化剂之一,但仍存在低碳醇时空收率不理想、反应网络复杂、产物分布难以调控及稳定性差等问题,高效稳定催化剂的开发极具挑战。本文首先从热力学上分析了CO/CO_(2)加氢反应制低碳醇适宜的工艺条件;其次,对改性费托合成催化剂上CO/CO_(2)加氢制低碳醇的反应路径进行了解析,并据此提出催化剂的设计思路。随后,介绍了铁基和钴基催化剂的研究现状,详细阐述了前体结构、助剂、金属-载体相互作用等因素对催化剂性能的影响机制,重点分析了高性能催化剂的构建策略。后续可借助于先进表征技术和理论计算进一步加深对反应机理的认识,并通过催化剂结构的精细调控,获取低碳醇时空收率和催化剂稳定性的提升策略。

关键词：合成气二氧化碳低碳醇加氢催化剂

High-order time-reversal symmetry breaking normal state

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： Meng zeng Lun-Hui Hu Hong-Ye Hu Yi-zhuang You Congjun Wu Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA Department of Physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional superconductors.When two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type Z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap functions.In contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is intact.The phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is disordered.If θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal state.In both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry breaking.We employ an effective two-component XY-model assisted by a renormalization group analysis to address this problem.As a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)disordered.This is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature Z_(2)-breaking charge-2e superconducting phase.Our results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

Enhanced photocatalytic N_(2) fixation using KNbO3/Bi_(4)O_(5)Br_(2) type II heterojunction

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 85-97页

作者： Lin Yue Zhihao zeng Xujie Ren Shude Yuan Chuanqi Xia Xin Hu Leihong Zhao Lvchao zhuang Yiming He Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China Department of Materials Science and Engineering Zhejiang Normal UniversityJinhua 321004China

The fabrication of heterojunction catalysts is an effective strategy to enhance charge separation efficiency,thus boosting the performance of photocatalysts.This work presents the synthesis and investigation of a novel KNbO_(3)/Bi_(4)O_(5)Br_(2) heterostructure catalyst for photocatalytic N_(2)-to-NH_(3) conversion under light illumination.While morphology analysis revealed KNbO_(3) microcubes embedded within Bi_(4)O_(5)Br_(2) nanosheets,the composite exhibited no significant improvement in specific surface area or optical property compared to Bi_(4)O_(5)Br_(2) due to the relatively wide band gap and low surface area of KNbO_(3).The main contribution lies in the enhanced separation efficiency of photogenerated electrons and holes.Besides,the band structure analysis suggests that KNbO_(3) and Bi_(4)O_(5)Br_(2) exhibit suitable band potentials to form a type II heterojunction.Benefiting from the higher Fermi level of KNbO_(3) than Bi_(4)O_(5)Br_(2),the electron drift at the contact region thus occurs and leads to the formation of a built-in electric field with the direction from KNbO_(3) to Bi_(4)O_(5)Br_(2),accelerating electron migration and improving the operational efficiency of the photocatalysts.Consequently,the KNbO_(3)/Bi_(4)O_(5)Br_(2) catalyst shows an increased photoactivity,achieving an NH_(3) generation rate 1.78 and 1.58 times those of KNbO_(3) and Bi_(4)O_(5)Br_(2),respectively.This work may offer valuable insights for the design and synthesis of heterojunction composite photocatalysts.

关键词： KNbO_(3)/Bi_(4)O_(5)Br_(2) heterojunction photocatalytic N_(2)fixation charge separation

Language Adaptation for Entity Relation Classification via Adversarial Neural Networks

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Journal of Computer Science & Technology 2021年第1期36卷 207-220页

作者： Bo-Wei Zou Rong-Tao Huang zeng-zhuang Xu Yu Hong Guo-Dong Zhou School of Computer Science and Technology Soochow UniversitySuzhou 215006China Institute for Infocomm Research Agency for ScienceTechnology and ResearchSingapore 138635Singapore

Entity relation classification aims to classify the semantic relationship between two marked entities in a given sentence,and plays a vital role in various natural language processing applications.However,existing studies focus on exploiting mono-lingual data in English,due to the lack of labeled data in other languages.How to effectively benefit from a richly-labeled language to help a poorly-labeled language is still an open problem.In this paper,we come up with a language adaptation framework for cross-lingual entity relation classification.The basic idea is to employ adversarial neural networks(AdvNN)to transfer feature representations from one language to another.Especially,such a language adaptation framework enables feature imitation via the competition between a sentence encoder and a rival language discriminator to generate effective representations.To verify the effectiveness of AdvNN,we introduce two kinds of adversarial structures,dual-channel AdvNN and single-channel AdvNN.Experimental results on the ACE 2005 multilingual training corpus show that our single-channel AdvNN achieves the best performance on both unsupervised and semi-supervised scenarios,yielding an improvement of 6.61%and 2.98%over the state-of-the-art,respectively.Compared with baselines which directly adopt a machine translation module,we find that both dual-channel and single-channel AdvNN significantly improve the performances(F1)of cross-lingual entity relation classification.Moreover,extensive analysis and discussion demonstrate the appropriateness and effectiveness of different parameter settings in our language adaptation framework.

关键词： adversarial neural network entity relation classification language adaptation

Accurate prediction of myopic progression and high myopia by machine learning

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Precision Clinical Medicine 2024年第1期7卷 14-20页

作者： Jiahui Li Simiao zeng Zhihuan Li Jie Xu Zhuo Sun Jing Zhao Meiyan Li Zixing Zou Taihua Guan Jin zeng zhuang Liu Wenchao Xiao Ran Wei Hanpei Miao Ian Ziyar Junxiong Huang Yuanxu Gao Yangfa zeng Xing-Tao Zhou Kang Zhang Guangzhou Women and Children's Medical Center Guangzhou Medical UniversityGuangzhou 510120China Guangzhou National Laboratory Guangzhou 510o0oChina Zhuhai International Eye Center of the First Affliated Hospital of Faculty of Medicine Macao University of Science and TechnologyZhuhai 519000China Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100069China Key Laboratory of Myopia Ministry of HealthShanghai Key Laboratory of Visual Impairment and RestorationDepartment of OphthalmologyEye InstituteEye and EarNoseand Throat HospitalFudan UniversityShanghai 200031China DongguanPeople's Hospital The First School of Clinical MedicinelSouthern Medical UniversityDongguan 523059China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060China Wenzhou Eye Hospital and Institute for Advanced Study on Eye Health and Diseases Wenzhou Medical UniversityWenzhou 32500oChina

Background Myopia is a leading cause of visual impairment in Asia and worldwide.However,accurately predicting the progression of myopia and the high risk of myopia remains a challenge.This study aims to develop a predictive model for the development of myopia.Methods We first retrospectively gathered 612530 medical records from five independent cohorts,encompassing 227543 patients ranging from infants to young adults.Subsequently,we developed a multivariate linear regression algorithm model to predict the progression of myopia and the risk of high myopia.Result The model to predict the progression of myopia achieved an R^(2) value of 0.964 vs a mean absolute error(MAE)of 0.119D[95%confidence interval(CI):0.119,1.146]in the internal validation set.It demonstrated strong generalizability,maintaining consistent performance across external validation sets:R^(2)=0.950 vs MAE=0.119D(95%CI:0.119,1.136)in validation study 1,R^(2)=0.950 vs MAE=0.121D(95%CI:0.121,1.144)in validation study 2,and R^(2)=0.806 vs MAE=−0.066D(95%CI:−0.066,0.569)in the Shanghai Children Myopia Study.In the Beijing Children Eye Study,the model achieved an R^(2) of 0.749 vs a MAE of 0.178D(95%CI:0.178,1.557).The model to predict the risk of high myopia achieved an area under the curve(AUC)of 0.99 in the internal validation set and consistently high area under the curve values of 0.99,0.99,0.96 and 0.99 in the respective external validation sets.Conclusion Our study demonstrates accurate prediction of myopia progression and risk of high myopia providing valuable insights for tailoring strategies to personalize and optimize the clinical management of myopia in children.

关键词： myopia progression machine learning prevention precision medicine

Cinobufotalin prevents bone loss induced by ovariectomy in mice through the BMPs/SMAD and Wnt/β-catenin signaling pathways

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Animal Models and Experimental Medicine 2024年第3期7卷 208-221页

作者： Da-zhuang Lu Li-jun zeng Yang Li Ran-li Gu Meng-long Hu Ping Zhang Peng Yu Xiao Zhang Zheng-wei Xie Hao Liu Yong-sheng Zhou Department of Prosthodontics Peking University School and Hospital of StomatologyBeijingChina National Center of Stomatology BeijingChina National Clinical Research Center for Oral Diseases BeijingChina Beijing Key Laboratory of Digital Stomatology BeijingChina Department of Cariology and Endodontology Peking University School and Hospital of StomatologyBeijingChina Peking University International Cancer Institute Peking University Health Science CenterPeking UniversityBeijingChina Central Laboratory Peking University School and Hospital of StomatologyBeijingChina National Engineering Research Center of Oral Biomaterials and Digital Medical Devices BeijingChina

Background:Osteoporosis is a chronic bone disease characterized by bone loss and decreased bone strength.However,current anti-resorptive drugs carry a risk of various complications.The deep learning-based efficacy prediction system(DLEPS)is a forecasting tool that can effectively compete in drug screening and prediction based on gene expression changes.This study aimed to explore the protective effect and potential mechanisms of cinobufotalin(CB),a traditional Chinese medicine(TCM),on bone loss.Methods:DLEPS was employed for screening anti-osteoporotic agents according to gene profile changes in primary osteoporosis.Micro-CT,histological and morphological analysis were applied for the bone protective detection of CB,and the osteogenic differentiation/function in human bone marrow mesenchymal stem cells(hBMMSCs)were also investigated.The underlying mechanism was verified using qRT-PCR,Western blot(WB),immunofluorescence(IF),etc.Results:A safe concentration(0.25mg/kg in vivo,0.05μM in vitro)of CB could effectively preserve bone mass in estrogen deficiency-induced bone loss and promote osteogenic differentiation/function of hBMMSCs.Both BMPs/SMAD and Wnt/β-catenin signaling pathways participated in CB-induced osteogenic differentiation,further regulating the expression of osteogenesis-associated factors,and ultimately promoting osteogenesis.Conclusion:Our study demonstrated that CB could significantly reverse estrogen deficiency-induced bone loss,further promoting osteogenic differentiation/function of hBMMSCs,with BMPs/SMAD and Wnt/β-catenin signaling pathways involved.

关键词： BMPs/SMAD bone loss cinobufotalin hBMMSCs osteogenesis osteoporosis Wnt/β-catenin signaling pathways

微波技术在分子筛材料合成及应用中的研究进展

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石油炼制与化工 2023年第8期54卷 127-133页

作者：杜金涛赵保槐曾壮苑志伟曾双亲鲍俊中国石化催化剂有限公司工程技术研究院北京101111 中石化石油化工科学研究院有限公司

综述了微波技术在分子筛材料合成、改性和应用中的研究进展,包括微波合成常规分子筛、纳米分子筛、复合分子筛及分子筛膜,微波强化分子筛改性、离子交换、催化反应及分子脱附,以及用于合成分子筛的微波设备等。与传统间接加热方式相比,... 详细信息

综述了微波技术在分子筛材料合成、改性和应用中的研究进展,包括微波合成常规分子筛、纳米分子筛、复合分子筛及分子筛膜,微波强化分子筛改性、离子交换、催化反应及分子脱附,以及用于合成分子筛的微波设备等。与传统间接加热方式相比,微波可以实现瞬间、直接的体相加热,因而在分子筛材料的合成和应用中具有更快速、更节能、更高效、更环保的特点,其特殊的加热方式还可能改变分子的反应路径,因而具有重大应用潜力。此外,微波可以有效提高分子筛材料的晶化效率,调节孔径结构、粒径分布、微观形貌及分子筛膜厚度,强化离子交换速率,加速催化反应和分子脱附速率,为分子筛材料的合成和应用开辟新方向。

关键词：催化剂分子筛微波加热过程强化

High-fat diet impairs gut barrier through intestinal microbiota-derived reactive oxygen species

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Science China(Life Sciences) 2024年第5期67卷 879-891页

作者： Nianyi zeng Fan Wu Junqi Lu Xiang Li Shaomei Lin Lang Zhou Zhongwei Wang Guangyan Wu Qingfa Huang Daowen Zheng Jie Gao Shan Wu Xiaojiao Chen Muxuan Chen Fanguo Meng Haitao Shang Yan He Peng Chen Hong Wei zhuang Li Hongwei Zhou Microbiome Medicine Center Department of Laboratory MedicineZhujiang HospitalSouthern Medical UniversityGuangzhou 510282China Department of Environmental Health Guangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public Health and Tropical MedicineSouthern Medical UniversityGuangzhou 510515China Redox Medical Center for Public Health Soochow UniversitySuzhou 215301China Precision Medicine Institute The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Department of Pathophysiology Guangdong Provincial Key Laboratory of ProteomicsSchool of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China

Gut barrier disruption is a key event in bridging gut microbiota dysbiosis and high-fat diet(HFD)-associated metabolic disorders.However,the underlying mechanism remains elusive.In the present study,by comparing HFD-and normal diet(ND)-treated mice,we found that the HFD instantly altered the composition of the gut microbiota and subsequently damaged the integrity of the gut barrier.Metagenomic sequencing revealed that the HFD upregulates gut microbial functions related to redox reactions,as confirmed by the increased reactive oxygen species(ROS)levels in fecal microbiota incubation in vitro and in the lumen,which were detected using in vivo fluorescence imaging.This microbial ROS-producing capability induced by HFD can be transferred through fecal microbiota transplantation(FMT)into germ-free(GF)mice,downregulating the gut barrier tight junctions.Similarly,mono-colonizing GF mice with an Enterococcus strain excelled in ROS production,damaged the gut barrier,induced mitochondrial malfunction and apoptosis of the intestinal epithelial cells,and exacerbated fatty liver,compared with other low-ROS-producing Enterococcus strains.Oral administration of recombinant high-stability-superoxide dismutase(SOD)significantly reduced intestinal ROS,protected the gut barrier,and improved fatty liver against the HFD.In conclusion,our study suggests that extracellular ROS derived from gut microbiota play a pivotal role in HFD-induced gut barrier disruption and is a potential therapeutic target for HFD-associated metabolic diseases.

关键词： fatty liver disease gut microbiota gut barrier high-fat diet oxidative stress reactive oxygen species

Research and Development on Short Gap Streamer Discharge Simulation Methods

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中国电机工程学报 2012年第22期32卷 I0021-I0021,5页

作者： zhuang Chijie zeng Rong Tsinghua University

流注放电是间隙放电研究的重要内容与切入点,仅靠实验手段仍然无法获得流注放电的微观机制及放电通道内的全部物理参数,因此,数值仿真成为推动流注放电理论发展的一种重要方法。文章阐述了短间隙流注放电仿真的流体模型及其假设,分析了... 详细信息

流注放电是间隙放电研究的重要内容与切入点,仅靠实验手段仍然无法获得流注放电的微观机制及放电通道内的全部物理参数,因此,数值仿真成为推动流注放电理论发展的一种重要方法。文章阐述了短间隙流注放电仿真的流体模型及其假设,分析了数值仿真算法中的3个难点问题,即粒子输运方程的准确求解、不规则区域中泊松方程的快速求解以及光电离项的快速求解。在回顾流注放电数值仿真领域解决上述3个难点问题的历史过程与取得进展的基础上,提出了解决上述问题的可能途径与努力方向。

关键词：流光放电研究与发展模拟方法间隙仿真方法放电过程实验数据数值模拟