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Improving photosensitization for photochemical CO2-to-CO conversion

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National Science Review 2020年第9期7卷 1459-1467页

作者： Ping Wang Ru Dong Song Guo Jianzhang Zhao Zhi-ming zhang Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and EngineeringTianjin University of Technology State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology

Inspired by nature, improving photosensitization represents a vital direction for the development of artificial photosynthesis. The sensitization ability of photosensitizers(PSs) reflects in their electron-transfer ability, which highly depends on their excited-state lifetime and redox potential. Herein, for the first time,we put forward a facile strategy to improve sensitizing ability via finely tuning the excited state of Ru(Ⅱ)-PSs(Ru-1–Ru-4) for efficient CO2reduction. Remarkably, [Ru(Phen)2(3-pyrenyl Phen)]2+(Ru-3) exhibits the best sensitizing ability among Ru-1–Ru-4, over 17 times higher than that of typical Ru(Phen)32+. It can efficiently sensitize a dinuclear cobalt catalyst for CO2-to-CO conversion with a maximum turnover number of 66 480. Systematic investigations demonstrate that its long-lived excited state and suitable redox driving force greatly contributed to this superior sensitizing ability. This work provides a new insight into dramatically boosting photocatalytic CO2reduction via improving photosensitization.

关键词： photosensitization photocatalysis CO2 reduction excited state Ru(II) complexes

Analytical modeling of complex contact behavior between rock mass and lining structure

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Journal of Rock Mechanics and Geotechnical engineering 2022年第3期14卷 813-824页

作者： Dingli zhang Tong Xu Huangcheng Fang Qian Fang Liqiang Cao ming Wen Key Laboratory for Urban Underground engineering of the Ministry of Education Beijing Jiaotong UniversityBeijing100044China College of Civil and Transportation engineering Shenzhen UniversityShenzhen518060China China Academy of Transportation Sciences Beijing100029China

Based on the nondestructive test data of operating railway tunnels in China, this paper summarizes the basic characteristics of the complex contact behavior between the rock mass and lining structure. The contact modes are classified into dense contact, local non-contact, and loose contact. Subsequently, the corresponding mechanical model for each contact mode is developed according to its mechanical characteristics using the complex variable method. In the proposed mechanical model, a special algorithm is introduced to detect whether the local non-contact zone is re-contacted. Besides, a novel conformal mapping method is also proposed to accurately calculate the mechanical response of the concrete lining. Finally, the accuracy of the proposed method is verified by comparing it with the finite element method(FEM). Several parameter investigations are conducted to analyze the effects of different contact modes on the rock-lining interaction. The results show that:(i) the height of the local noncontact area does not have a significant effect on the contact stress distribution if no re-contact occurs;(ii) backfill grouting can reduce the local stress concentration caused by poor contact modes;and(iii) reducing the friction coefficient of the interface can lead to a more uniform distribution of internal forces in the concrete lining.

关键词： Loose contact Local non-contact Tunnel lining Complex variable method Analytical mechanical model

α-ketoglutarate promotes the specialization of primordial germ cell-like cells through regulating epigenetic reprogramming

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The Journal of Biomedical Research 2021年第1期35卷 36-46,I0014-I0016页

作者： ming Xing Na Wang Hanyi Zeng Jun zhang State Key Laboratory of Reproductive Medicine Department of Histology and EmbryologyNanjing Medical UniversityNanjingJiangsu 211166China

There is growing evidence that cellular metabolism can directly participate in epigenetic dynamics and consequently modulate gene ***,the role of metabolites in activating the key gene regulatory network for specialization of germ cell lineage remains largely ***,we identified some cellular metabolites with significant changes by untargeted metabolomics between mouse epiblast-like cells(EpiLCs)and primordial germ cell-like cells(PGCLCs).More importantly,we found that inhibition of glutaminolysis by bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl)ethyl sulfide(BPTES)impeded PGCLC specialization,but the impediment could be rescued by addition ofα-ketoglutarate(αKG),the intermediate metabolite of oxidative phosphorylation and ***,adding aKG alone to the PGCLC medium accelerated the PGCLC specialization through promoting H3 K27 me3 ***,our study reveals the importance of metabolite aKG in the germ cell fate determination and highlights the essential role of cellular metabolism in shaping the cell identities through epigenetic events.

关键词： cellular metabolism α-ketoglutarate primordial germ cells epigenome

The Mineral Composition and Sources of the Fine-Grained Sediments from the 49.6?E Hydrothermal Field at the SWIR

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Journal of Ocean University of China 2020年第1期19卷 60-68页

作者： zhang Wenqiang SUN Xiaoxia FAN Dejiang LIU ming JIA Qi YANG Zuosheng Key Laboratory of Submarine Geosciences and Technology MOEOcean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China

We used the X-ray diffraction method to determine systematically the mineral phases in bulk sediment samples and acid undissolved residuals of the fine-grained fraction of the surface sediments from the 49.6°E hydrothermal field at the Southwest Indian Ridge(SWIR)and discussed the mineral sources of the surface *** results showed that the surface sediments in this region were composed of calcareous ooze,and calcite was the dominant *** sediments also contained quartz,feldspar,clay minerals,pyroxene,sphalerite,barite,serpentine,and *** quartz,feldspar,and clay minerals were exogenous minerals that mainly originated from the Namib and Kalahari deserts in southern *** pyroxene,serpentine,magnetite,sphalerite,calcite,and barite were endogenous minerals from weathering of seafloor basement rocks and seafloor hydrothermal *** sulfide particles in the sediments were mainly deposited from upwelling plumes.

关键词： Southwest Indian Ridge surface sediment mineral source hydrothermal

Synthesis and characterization of high strength polyimide/silicon nitride nanocomposites with enhanced thermal and hydrophobic properties

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Chinese Journal of Chemical engineering 2021年第4期34卷 446-453页

作者： Tadele Daniel Mekuria Lei Wang Chunhong zhang ming Yang Qingtao Lv Diaa Eldin Fouad Polymer Materials Research Center Key Laboratory of Superlight Materials and Surface TechnologyMinistry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Chemistry Department College of Natural and Computational SciencesAssosa UniversityEthiopia

Polyimide(PI)composite films were synthesized incorporating amino modified silicon nitride(Si_(3)N_(4))nanoparticles into PI matrix via in situ polymerization *** mechanical and thermal performances as well as the hydrophobic properties of the as prepared composite films were investigated with respect to the dosage of the filler in the PI *** to Thermogravimetric(TGA)analysis,meaningful improvements were achieved in T5(5%weight loss temperature)and T10(10%weight loss temperature)up to 54.1℃ and 52.4℃,respectively when amino functionalized nano Si_(3)N_(4) particles were introduced into the PI *** differential scanning calorimetry(DSC)results revealed that the glass transition temperature(Tg)of the composites was considerably enhanced up to 49.7℃ when amino functionalized Si_(3)N_(4) nanoparticles were incorporated in the PI *** to the neat PI,the PI/Si_(3)N_(4) nanocomposites exhibited very high improvement in the tensile strength as well as Young’s modulus up to 105.4%and 138.3%,*** to the neat PI,the composites demonstrated highly decreased water absorption behavior which showed about 68.1%enhancement as the content of the nanoparticles was increased to 10 wt%.The SEM(Scanning electron microscope)images confirmed that the enhanced thermal,mechanical and water proof properties are essentially attributed to the improved compatibility of the filler with the matrix and hence,enhanced distribution inside the matrix because of the amino groups on the surface of Si_(3)N_(4) nanoparticles obtained from surface functionalization.

关键词： Silicon nitride(Si_(3)N_(4))nanoparticles Polyimide composites Mechanical properties Thermal properties Hydrophobicity

Light-and Heat-Controlled Formation of Osmanaphthalenes and Osmanaphthalynes

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Chinese Journal of Chemistry 2022年第24期40卷 2853-2860页

作者： ming-Xing zhang Xiaofei Yang Zhiqiang Xu Jun Yin Sheng Hua Liu Key Laboratory of Pesticide and Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhanHubei430079 China Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients College of Chemistry and Life ScienceHubei University of EducationWuhanHubei430205 China Key Laboratory for Green Chemical Process of Ministry of Education School of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhanHubei430205 China

mple and efficient synthesis of metalla-aromatics with tailored distinctive optical,magnetic,redox,and light-emitting properties is attractive yet *** have now successfully synthesized three paramagnetic osmanaphthalenes bearing different electron-donating groups as well as the first osmabenzo[b]carbazole containing an osmanaphthalene unit with four fused rings in good yields by subjecting suitable osmium carbyne precursors to a visible-light-induced *** contrast,the four corresponding diamagnetic cyclic metal carbynes containing an osmanaphthalyne unit were obtained from the same osmium carbyne precursors by a heating *** lowest-energy absorptions of the paramagnetic osmanaphthalenes are red-shifted compared to the corresponding ***,experimental observations including X-ray analysis as well as nucleus-independent chemical shift(NICS),anisotropy of the current-induced density(AICD)calculations revealed these novel osmapolycycles bearing phosphonium substituents to be of aromatic character.

关键词： Metallacycles Aromaticity Osmanaphthalyne Osmanaphthalene Photolysis

A numerical method for simulating planar 3D multi-fracture propagation in multi-stage fracturing of horizontal wells

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Petroleum Exploration and Development 2020年第1期47卷 171-183页

作者： CHen ming zhang Shicheng XU Yun MA Xinfang ZOU Yushi China University of Petroleum Beijing 102249China Texas A&M University College Station 77840USA PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China The Key Laboratory of Research Stimulation PetroChinaLangfang 065007China

To resolve the issue of design for multi-stage and multi-cluster fracturing in multi-zone reservoirs, a new efficient algorithm for the planar 3 D multi-fracture propagation model was proposed. The model considers fluid flow in the wellbore-perforation-fracture system and fluid leak-off into the rock matrix, and uses a 3 D boundary integral equation to describe the solid deformation. The solid-fluid coupling equation is solved by an explicit integration algorithm, and the fracture front is determined by the uniform tip asymptotic solutions and shortest path algorithm. The accuracy of the algorithm is verified by the analytical solution of radial fracture, results of the implicit level set algorithm, and results of organic glass fracturing experiment. Compared with the implicit level set algorithm(ILSA), the new algorithm is much higher in computation speed. The numerical case study is conducted based on a horizontal well in shale gas formation of Zhejiang oilfield. The impact of stress heterogeneity among multiple clusters and perforation number distribution on multi-fracture growth and fluid distribution among multiple fractures are analyzed by numerical simulation. The results show that reducing perforation number in each cluster can counteract the effect of stress contrast among perforation clusters. Adjusting perforation number in each cluster can promote uniform flux among clusters, and the perforation number difference should better be 1-2 among clusters. Increasing perforation number in the cluster with high in situ stress is conducive to uniform fluid partitioning. However, uniform fluid partitioning is not equivalent to uniform fracture geometry. The fracture geometry is controlled by the stress interference and horizontal principal stress profile jointly.

关键词： horizontal well multi-stage fracturing multi-fracture growth 3D boundary element planar stress heterogeneity perforation optimization

Conceptualizing the complexity of ferroptosis to treat triple-negative breast cancer:theory-to-practice

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Cancer Biology & Medicine 2023年第2期20卷 98-103页

作者： Hang zhang Fan Yang Yi Xiao Yi-Zhou Jiang Zhi-ming Shao Key Laboratory of Breast Cancer in Shanghai Department of Breast SurgeryFudan University Shanghai Cancer Center、Department of OncologyShanghai Medical CollegeFudan UniversityShanghai 200032China

Ferroptosis,a type of regulated cell death named one decade ago,is a unique type driven by lipid peroxidation in an iron-dependent *** differs radically from apoptosis and other regulated forms of cell death in both morphology and molecular *** can be triggered by a variety of physiologic conditions and pathologic *** has been growing interest in ferroptosis in recent years,and research on ferroptosis is productive.

关键词： peroxidation death breast

数字乡村建设对防返贫能力的影响及空间效应研究

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经济研究参考 2024年第9期 121-140页

作者：郭文强韦星羽雷明张雯苹新疆财经大学信息管理学院北京大学乡村振兴研究院北京大学光华管理学院新疆财经大学

防止规模性返贫是扎实推进乡村振兴的关键所在,数字乡村建设对提升农村防返贫能力具有重要意义。本文基于2016~2022年中国30个省(区、市)的面板数据,运用基于加速遗传算法的投影寻踪模型测度数字乡村建设水平与防返贫能力,通过核密度估... 详细信息

防止规模性返贫是扎实推进乡村振兴的关键所在,数字乡村建设对提升农村防返贫能力具有重要意义。本文基于2016~2022年中国30个省(区、市)的面板数据,运用基于加速遗传算法的投影寻踪模型测度数字乡村建设水平与防返贫能力,通过核密度估计刻画两者的时空分异特征,利用空间杜宾模型深入分析数字乡村建设对防返贫能力的空间溢出效应。研究发现:2016~2022年,数字乡村建设水平与防返贫能力整体上在不断提高,数字乡村建设存在多极化趋势,防返贫能力两极化现象逐渐减弱。农村防返贫能力具有显著的空间聚集特征,主要表现为“高—高”和“低—低”聚集模式。空间杜宾溢出效应分解表明:数字乡村建设对防返贫有着显著的正向影响以及正的空间溢出效应。据此,对未来建设数字乡村提出相关建议,并探索出提升防返贫能力的新路径,未来可尝试从溢出边界进一步探索空间溢出效应。

关键词：数字乡村防返贫投影寻踪模型加速遗传算法空间杜宾模型