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Synthesis of ordered mesoporous crystalline boron phosphate scaffold with double diamond surface structure

Science China chemistry 2024年

作者： Chao wang Wen-Duo Lu Jiao wang Shun-Ai che An-Hui Lu Lu Han School of chemical Science and Engineering Tongji University State Key Laboratory of Fine chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical Engineering Dalian University of Technology School of chemistry and chemical Engineering Frontiers Science Center for Transformative Molecules State Key Laboratory of Metal Matrix Composites Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

Ordered mesoporous materials have received great attention due to their well-defined pore structures and potential applications in catalysis, adsorption, separation, drug delivery, etc. Although various compositions of mesoporous solids have been successfully prepared, the preparation of crystalline non-metallic oxyacid salts with ordered mesoporosity remains a major challenge. Herein, we report the synthesis of a mesoporous solid acid crystalline boron phosphate（BPO4） catalyst with a bicontinuous shifted double diamond（SDD） hyperbolic surface structure. The BPO4scaffold was obtained by synergistic selfassembly in a mixed solvent of water and tetrahydrofuran using the diblock copolymer poly（ethylene oxide）-block-polystyrene as template and phosphoric acid and orthoboric acid as inorganic sources. The structure consists of two sets of diamond networks adjacent to each other with a mesostructural scale tetragonal symmetry（space group I41/amd） with unit cell parameters of a =80 nm and c = 113 nm, which affords the scaffold a specific surface area of 44 m2/g. As a solid acid catalytic material, the SDD BPO4scaffold exhibited excellent catalytic activity at room temperature with a conversion of furfural to 2-（dimethoxymethyl）furan over 70% and can be reused after recovery without serious loss of activity. In the propane oxidative dehydrogenation reaction, SDD BPO4demonstrated high olefin productivity and selectivity while maintaining high reaction rate. This study provides ideas for the preparation of ordered mesoporous crystalline catalytic materials and demonstrates their potential for practical applications.

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Effect of Different Reinforcing Fillers on Properties,Interfacial Compatibility and Weatherability of Wood-plastic Composites

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Journal of Bionic Engineering 2019年第2期16卷 337-353页

作者： Xiaoqian wang Zhiming Yu Armando g.McDonald MOE Key Laboratory of Wooden Material Science and Application Beijing Forestry UniversityQinghua East Road No.35Beijing 100083China Renewable Materials Program Department of ForestRangelandand Fire SciencesUniversity of Idaho875 Perimeter Drive MS 1133MoscowIdaho 83844-1133USA

Utilization of biochar in plastic based blends offers a sustainable way to renewable materials as well as value-added use of wood *** investigate the interfacial compatibility and weatherability properties of biochar composites,four types of Wood-Plastic Composites(WPC)were prepared by an extrusion *** mechanical properties,water absorptions,thermal and viscoelastic properties,and rheological behavior of the composites were also *** decolorizing carbon(NA)composite melts showed the higher modulus and viscosity,indicating better melt *** NA composites performed the best in tensile properties(strength of 2&6 MPa and modulus of 3.4 gPa)and had strong interfacial interaction between particles and the *** degree of HDPE crystallinity in the biochar and carbon composites decreased relative to Douglas-fir(DF)composites,while the thermal properties of the composites improved compared with DF *** the water resistance,the DF composites displayed the highest water absorption(3.7%)and thickness swell(2.9%).During accelerated weathering tests,longer exposure time increased the color change and lightness,especially for DF *** and biochar composites resulted in improved *** study opens up a pathway to utilize effectively the renewable biochar as reinforcing filler in WPC in outdoor applications.

关键词： biochar interfacial compatibility accelerated weathering wood-plastic composites

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Selenomethionine alleviates chronic heat stress-induced breast muscle injury and poor meat quality in broilers via relieving mitochondrial dysfunction and endoplasmic reticulum stress

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Animal Nutrition 2024年第1期16卷 363-375页

作者： Jinzhong Jing Jiayi wang Xiaoyu Xiang Shenggang Yin Jiayong Tang Longqiong wang gang Jia guangmang Liu Xiaoling chen gang Tian Jingyi Cai Bo Kang Lianqiang che Hua Zhao Key Laboratory for Animal Disease-Resistance Nutrition of Ministry of Education of China Ministry of Agriculture and Rural Affairsof Sichuan ProvinceAnimal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina College of Animal Science and Technology Sichuan Agricultural UniversityChengdu 611130SichuanChina

In the present study,the chronic heat stress(CHS)broiler model was developed to investigate the potential protection mechanism of organic selenium(selenomethionine,SeMet)on CHS-induced skeletal muscle growth retardation and poor meat *** hundred Arbor Acres male broilers(680±70 g,21 d old)were grouped into 5 treatments with 8 replicates of 10 broilers per *** in the control group were raised in a thermoneutral environment(22±2°C)and fed with a basal *** other four treatments were exposed to hyperthermic conditions(33±2°C,24 h in each day)and fed on the basal diet supplied with SeMet at 0.0,0.2,0.4,and 0.6 mg Se/kg,respectively,for 21 *** showed that CHS reduced(Pgrowth performance,decreased(Pght and impaired the meat quality of breast muscle in *** induced protein metabolic disorder in breast muscle,which increased(Pgenes,while decreased the protein expression of *** also decreased the antioxidant capacity and induced mitochondrial stress and endoplasmic reticulum(ER)stress in breast muscle,which increased(Pgulating the expression of the selenotranscriptome and several key selenoproteins,which increased(Pght,improved meat quality,enhanced antioxidant capacity and mitigated mitochondrial stress and ER ***'s more,SeMet suppressed protein degradation and improved protein biosynthesis though inhibiting the caspase and ubiquitin proteasome system and promoting the mTOR-4EBP1 *** conclusion,dietary SeMet supplementation increases the expression of several key selenoproteins

关键词： Broiler Chronic heat stress Skeletal muscle Meat quality Mitochondrial dysfunction Endoplasmic reticulum stress

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Object-Oriented Design for FDTD Visual Scientific Computing

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Journal of Systems Engineering and Electronics 2001年第3期12卷 71-75页

作者： Dong, X. wang, W. wang, g. Electromagnetic and Commun. Lab. Sch. of Electronic and Info. Eng. Xi'an Jiaotong University Xi'an 710049 China

A scheme for general purposed FDTD visual scientific computing software is introduced in this paper using object-oriented design (OOD) method. By abstracting the parameters of FDTD grids to an individual class and separating from the iteration procedure, the visual software can be adapted to more comprehensive computing problems. Real-time gray degree graphic and wave curve of the results can be achieved using DirectX technique. The special difference equation and data structure in dispersive medium are considered, and the peculiarity of parameters in perfectly matched layer are also discussed.

关键词： Computational methods Computer aided design Data structures Difference equations Finite difference method Iterative methods Natural sciences computing Object oriented programming Parameter estimation Three dimensional computer graphics Time domain analysis

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Amorphous Sn modified nitrogen-doped porous carbon nanosheets with rapid capacitive mechanism for highcapacity and fast-charging lithium-ion batteries

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Frontiers of Materials Science 2023年第3期17卷 107-118页

作者： Chong Xu guang Ma wang Yang Sai che Neng chen Ni Wu Bo Jiang Ye wang Yankun Sun Sijia Liao Jiahao Yang Xiang Li guoyong Huang Yongfeng Li State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China

Sn-based materials are considered as a kind of potential anode materials for lithium-ion batteries(LIBs)owing to their high theoretical ***,their use is limited by large volume expansion deriving from the lithiation/delithiation *** this work,amorphous Sn modified nitrogen-doped porous carbon nanosheets(ASnNPCNs)are *** synergistic effect of amorphous Sn and high edge-nitrogendoped level porous carbon nanosheets provides ASn-NPCNs with multiple advantages containing abundant defect sites,high specific surface area(214.9 m^(2)·g^(−1)),and rich hierarchical pores,which can promote the lithium-ion *** as the LIB anode,the as-prepared ASn-NPCNs-750 electrode exhibits an ultrahigh capacity of 1643 mAh·g^(−1) at 0.1 A·g^(−1),ultrafast rate performance of 490 mAh·g^(−1) at 10 A·g^(−1),and superior long-term cycling performance of 988 mAh·g^(−1) at 1 A·g^(−1) after 2000 cycles with a capacity retention of 98.9%.Furthermore,the in-depth electrochemical kinetic test confirms that the ultrahigh-capacity and fast-charging performance of the ASn-NPCNs750 electrode is ascribed to the rapid capacitive *** impressive results indicate that ASn-NPCNs-750 can be a potential anode material for high-capacity and fast-charging LIBs.

关键词： amorphous Sn rapid capacitive mechanism lithium-ion storage nitrogen-doped carbon fast charging

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CO_2 permeability of fractured coal subject to confining pressures and elevated temperature: Experiments and modeling

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Science China(Technological Sciences) 2016年第12期59卷 1931-1942页

作者： JU Yang wang Jianguo wang HuiJie ZHENg JiangTao RANJITH Pathegama g gAO Feng State Key Laboratory for geomechanics & Deep Underground Engineering China University of Mining & Technology State Key Laboratory of Coal Resources & Safe Mining China University of Mining & Technology College of Engineering Peking University Department of Engineering Mechanics School of AerospaceTsinghua University Department of Civil Engineering Monash University

The CO_2 permeability of fractured coal is of great significance to both coalbed gas extraction and CO_2 storage in coal seams, but the effects of high confining pressure, high injection pressure and elevated temperature on the CO_2 permeability of fractured coal with different fracture extents have not been investigated thoroughly. In this paper, the CO_2 permeability of fractured coals sampled from a Pingdingshan coal mine in China and artificially fractured to a certain extent is investigated through undrained triaxial tests. The CO_2 permeability is measured under the confining pressure with a range of 10–25 MPa, injection pressure with a range of 6–12 MPa and elevated temperature with a range of 25–70°C. A mechanistic model is then proposed to characterize the CO_2 permeability of the fractured coals. The effects of thermal expansion, temperature-induced reduction of adsorption capacity, and thermal micro-cracking on the CO_2 permeability are explored. The test results show that the CO_2 permeability of naturally fractured coal saliently increases with increasing injection pressure. The increase of confining pressure reduces the permeability of both naturally fractured coal and secondarily fractured coal. It is also observed that initial fracturing by external loads can enhance the permeability, but further fracturing reduces the permeability. The CO_2 permeability decreases with the elevation of temperature if the temperature is lower than 44°C, but the permeability increases with temperature once the temperature is beyond 44°C. The mechanistic model well describes these compaction mechanisms induced by confining pressure, injection pressure and the complex effects induced by elevated temperature.

关键词： CO2 permeability fractured coal confining pressure elevated temperature thermal effects mechanistic models

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STUDIES ON THE SYNTHESES OF FAVELINES

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Chinese chemical Letters 1996年第2期7卷 107-108页

作者： Lin, g wang, XC Pan, XF LANZHOU UNIV NATL LAB APPL ORGAN CHEMDEPT CHEMLANZHOU 730000PEOPLES R CHINA

A novel and efficient convergent synthesis of 13-demethyldeoxofaveline. a key intermediate for deoxofaveline, faveline and faveline methyl ether, was achieved by Wittig reaction and selective oxidation. And a novel si...

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Nanoindentation of soft solids by a fla punch

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Acta Mechanica Sinica 2015年第4期31卷 531-535页

作者： g.F.wang X.R.Niu Department of Engineering Mechanics SVL Xi’an Jiaotong University Department of Mechanical and Biomedical Engineering City University of Hong Kong

Measuring the surface tension and elastic mod- ulus of soft materials and biological tissues under different physiological and pathological conditions is of significance for understanding various phenomena associated with defor- mation. In this paper, the nanoindentation of a circular fiat punch on a soft solid is analyzed with the influence of surface tension. By solving the corresponding singular integral equa- tion, the relation between load and indent depth is obtained. When the radius of the flat punch shrinks to the same order as the ratio of surface tension to elastic modulus, surface ten- sion significantly affects the indentation load-depth relation, which provides a facile method to measure surface tension in soft solids and biological tissues.

关键词： Nanoindentation Surface tension Soft solid Biological tissue

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Compliance Analysis of a 3-DOF Spindle Head by Considering gravitational Effects

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 1-10页

作者： LI Qi wang Manxin HUANg Tian cheTWYND g Derek Key Lab of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University School of Engineering University of Warwick

The compliance modeling is one of the most significant issues in the stage of preliminary design for parallel kinematic machine（PKM）. The gravity ignored in traditional compliance analysis has a significant effect on pose accuracy of tool center point（TCP） when a PKM is horizontally placed. By taking gravity into account, this paper presents a semi-analytical approach for compliance analysis of a 3-DOF spindle head named the A3 head. The architecture behind the A3 head is a 3-RPS parallel mechanism having one translational and two rotational movement capabilities, which can be employed to form the main body of a 5-DOF hybrid kinematic machine especially designed for high-speed machining of large aircraft components. The force analysis is carried out by considering both the externally applied wrench imposed upon the platform as well as gravity of all moving components. Then, the deflection analysis is investigated to establish the relationship between the deflection twist and compliances of all joints and links using semi-analytical method. The merits of this approach lie in that platform deflection twist throughout the entire task workspace can be evaluated in a very efficient manner. The effectiveness of the proposed approach is verified by the FEA and experiment at different configurations and the results show that the discrepancy of the compliances is less than 0.04 μm/N^-1 and that of the deformations is less than 10μm. The computational and experimental results show that the deflection twist induced by gravity forces of the moving components has significant bearings on pose accuracy of the platform, providing an informative guidance for the improvement of the current design. The proposed approach can be easily applied to the compliance analysis of PKM by considering gravitational effects and to evaluate the deformation caused by gravity throughout the entire workspace.

关键词： compliance modeling gravity spindle head

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Spatiotemporal variations in glacier area and surface velocity of the northern Antarctic Peninsula during 2018-2022

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Advances in Climate Change Research 2024年第2期15卷 297-311页

作者： Yu-Long KANg Shi-Chang KANg Wan-Qin gUO Tao che Zong-Li JIANg Zhen-Feng wang Qiang-Qiang XU che.g-De YANg State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100083China Key Laboratory of Remote Sensing of gansu Province Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Earth Sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China

Ice sheet serves as a crucial indicator for assessing climate *** loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface ***,observations of seasonal variability of ice speed are limited,and glacier-area changes require multi-temporal *** study investigated the changes in area and surface velocities of∼375 glaciers on the northern Antarctic Peninsula(NAP)utilizing satellite images acquired by the Sentinel 1&2 satellites during *** results indicate that the glacier area reduced by approximately 166.1±44.2 km^(2)(-0.2%±0.1%per year)during the study period,with an acceleration after 2020(-0.4%±0.3%per year),and the most dramatic reduction happened on the eastern *** maximum annual ice speeds on the NAP generally exceeded 3500 m per year,while the ice speeds in 2021 were the highest(exceeded 4210 m per year).The ice speed variability in austral autumn was higher than in other seasons,meanwhile the summer ice speeds showed an increasing *** glacier g012158E47018N,McNeile glacier,glacier g299637E64094S and Drygalski glacier showed the most remarkable ice speed variations represented by high daily velocities and strong fluctuations on their *** results demonstrated that the variations in glacier area and seasonal ice speed on the NAP were responsive to the ice-ocean-atmosphere ***,seasonal velocity and area variations should be considered when conducting accurate mass balance calculations,model validations and change mechanism analyses under climate warming scenarios.

关键词： glacier area Seasonal ice speed Sentinel 1&2 Northern Antarctic Peninsula Ice-ocean-atmosphere processes

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