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Evolution Mechanism of Carbon Covalent Bond during Coal Activation Using Mixed Atmosphere of H_(2)O and CO_(2)

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Journal of Thermal Science 2024年第5期33卷 1961-1973页

作者： wang Mingyue ZhanG Siyuan han Shaobo ZhanG Chi REN Qiangqiang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Coal Conversion Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China

Adequate destruction of the aromatic structure in coal is key to further reducing the emission of *** this research,activation reactions of Shenmu coal powder were carried out in a vertical tube *** study investigated the evolution mechanism of carbon covalent bonds during the activation process by altering the ratio of H_(2)O to CO_(2)in the activation *** theoretical validation was conducted through density functional *** two gas molecules follow different pathways to increase the reactivity of ***_(2)mainly participates in the cross-linking reaction by intensifying branching,while H_(2)O and char have lower adsorption energy barriers and are more likely to generate oxygen-containing functional *** molecules partially compete for active sites in a mixed gas atmosphere,but there is a synergism between the two *** synergism can be attributed to two *** inclusion of H_(2)O mitigates the generation of five-membered rings to a limited extent,while concurrently enhances the development of oxygen-containing functional *** oxygen-containing functional groups can effectively diminish the adsorption energy barrier associated with the interaction between gas molecules and char,consequently leading to a reduction in the energy demand for subsequent bond cleavage.

关键词： activation reaction carbon structure char CO_(2)/H_(2)O atmosphere density functional theory

Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production:Physicochemical characteristics and gasification kinetics analysis

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 268-281页

作者： han Dang Runsheng Xu Jianliang Zhang Mingyong wang Jinhua Li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Chemical Engineering The University of QueenslandQueensland 4072Australia

The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection *** results showed that after upgrading,the volatile content of biochar ranged from 16.19%to 45.35%,and the alkali metal content,ash content,and specific surface area were significantly *** optimal route for biochar pro-duction is hydrothermal carbonization-pyrolysis(P-HC),resulting in biochar with a higher calorific value,C=C structure,and increased graphitization *** apparent activation energy(E)of the sample ranges from 199.1 to 324.8 kJ/mol,with P-HC having an E of 277.8 kJ/mol,lower than that of raw biomass,primary biochar,and *** makes P-HC more suitable for blast furnace injection ***,the paper proposes a path for P-HC injection in blast furnaces and calculates potential environmental benefits.P-HC of-fers the highest potential for carbon emission reduction,capable of reducing emissions by 96.04 kg/t when replacing 40wt%coal injec-tion.

关键词： blast furnace injection biomass cross-upgrading hydrothermal carbonization pyrolysis physicochemical properties gasific-ation properties

Two types of coumarins-specific enzymes complete the last missing steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： Yucheng Zhao Yuedong He Liangliang han Libo Zhang Yuanzheng Xia Fucheng yin Xiaobing wang Deqing Zhao Sheng Xu Fei Qiao Yibei Xiao Lingyi Kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128China Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacology School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting diverse physiological and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring *** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific *** identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules Coumarins CYP450cyclase

Cadmium found in peanut (Arachis hypogaea L.) kernels mainly originates from root uptake rather than shell absorption from soil

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Pedosphere 2024年第4期34卷 726-735页

作者： Xin TANG Yurong wang Changfeng DING Yuepeng yin Zhigao ZHOU Taolin ZhanG Xingxiang wang CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Ecological Experimental Station of Red Soil Chinese Academy of SciencesYingtan 335211China

Roots and shells are two potential organs through which peanut plants absorb cadium(Cd)from soils;however,the relative contributions of the two uptake pathways(root uptake and shell absorption)to kernel Cd accumulation and their translocation characteristics are poorly *** this study,the relative contributions of the two pathways to Cd accumulation in two peanut cultivars,Xianghua2008(XH)and Yueyou43(YY),were accurately assessed by labeling rooting and podding zone soils with 113Cd and 111Cd isotopes(0.3 mg kg^(-1) dry soil),respectively,in a split-pot *** results showed that approximately 96%of the Cd accumulated in the peanut kernels was derived from root uptake,while only 4%originated from shell *** 1%of the Cd accumulated in whole peanut plants was attributed to shell absorption,of which 41%–44%was retained in shells and 56%–59%was translocated to *** contrast,the Cd absorbed by roots was efficiently translocated into all plant organs,of which 80%–84%was distributed in *** YY accumulated 1.3 times more Cd in whole plants than XH,the relative contributions of the two pathways to Cd accumulation in each plant organ were barely affected by peanut *** to the strong retention effect of shells,shell-derived Cd was approximately 2 times higher than root-derived Cd in *** results would improve the understanding of Cd accumulation processes in peanut plants,revealing that the root uptake pathway contributes predominantly to the Cd concentration in peanut kernels,based on which strategies and technology for the reduction of Cd in peanut plants could be designed and developed.

关键词： contamination heavy metal isotope-labeling technique relative contribution translocation factor uptake pathway

Tensile strength behavior of cement-stabilized dredged sediment reinforced by polypropylene fiber

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 380-392页

作者： Lei LANG Jiangshan LI Xin CHEN Lijun han Ping wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicChinese Academy of SciencesWuhan 430071China Hubei Provincial Key Laboratory of Contaminated Sludge and Soil Science and Engineering Wuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

This study evaluated the feasibility of using polypropylene fiber(PF)as reinforcement in improving tensile strength behavior of cement-stabilized dredged sediment(CDS).The effects of cement content,water content,PF content and length on the tensile strength and stress–strain behavioral evolutions were evaluated by conducting splitting tensile strength ***,the micro-mechanisms characterizing the tensile strength behavior inside PF-reinforced CDS(CPFDS)were clarified via analyzing macro failure and microstructure *** results indicate that the highest tensile strengths of 7,28,60,and 90 d CPFDS were reached at PF contents of 0.6%,1.0%,1.0%,and 1.0%,exhibiting values 5.96%,65.16%,34.10%,and 35.83%higher than those of CDS,***,3 mm,PF of showed the best reinforcement *** CPFDS exhibited obvious tensile strain-hardening characteristic,and also had better ductility than *** mix factor(C_(C)^(a)/C_(w)^(b))and time parameter(q_(t0)(t))of CDS,and the reinforcement index(k_(t-PF))of CPFDS were used to establish the tensile strength prediction models of CDS and CPFDS,considering multiple *** PF“bridge effect”and associated cementation-reinforcement coupling actions inside CPFDS were mainly responsible for tensile strength behavior *** key findings contribute to the use of CPFDS as recycled engineering soils.

关键词： dredged sediment chemical stabilization fiber reinforcement splitting tensile strength micro-mechanisms

Study of Seismic P Wave in Mesoscale Fracture-Induced Arbitrary Anisotropic Media

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Journal of Earth Science 2024年第2期35卷 717-721页

作者： han Xiao Xinmin Shang Zhentao wang Xiping wang Geophysical Research Institute SINOPEC Shengli Oilfield CompanyShandong 257022China Working Station for Postdoctoral Scientific Research Shengli OilfieldShandong 257000China

Mesoscale fracture controls the permeability of shale res ervoirs,it is one of the main research objectives of natural frac *** length of the mesoscale fracture is less than 1/4 of the seismic eigen wavelength and greater than 1%of the seis mic eigen wavelength,they cannot be identified in actual seis mic data and are usually displayed by the azimuthal anisotropy of seismic *** this paper,we propose a calculation process from fracture properties to seismic P-wave velocity and traveltime in anisotropic media induced by multiple sets of arbitrary occurring mesoscale *** on this process,the variations of the media’s Anisotropic(A-)parameters with fracture properties are ***,variation of P-wave NMO elliptical principle axis with the relative fracture density is studied according to the arbitrary anisotropic theory based on A-parameters.

关键词： seismic mesoscale shale

Study on force chain evolution of rice straw with different length during vibrational compression

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Particuology 2024年第2期85卷 310-322页

作者： han Tang Wenlong Xu Guixuan Zhu Changsu Xu Jinwu wang College of Engineering Northeast Agricultural UniversityHarbin150030China

This paper explores the mechanism of force chain evolution and voidage change under vibrational and non-vibrational compression conditions of rice straw of different *** were used to explore the force chain evolution and voidage variation mechanism under different *** re-sults show that under non-vibrational compression,the strong force chain passes from top to bottom in vertical direction and from center to periphery in tangential *** vibrational compression,the force chain passes from top and bottom to center in vertical direction and the force chain evolves from outer ring to interior and exterior in tangential *** number of strong chains,voidage and standard deviation of the mean pressure under vibratory compression are lower than the values under non-vibratory *** promotes stress transfer and enhancement,velocity enhancement and density *** study analyzes the mechanical properties of different lengths straw during vibrational and non-vibrational compression from a detailed viewpoint.

关键词： Straw compression Voidage Discrete element method Mechanical properties Force chain transmission

The biological functions and metabolic pathways of valine in swine

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Journal of Animal Science and Biotechnology 2024年第1期15卷 20-34页

作者： Chuni wang Yao Peng Yiru Zhang Juan Xu Sheng Jiang Leli wang Yulong yin Institute of Subtropical Agriculture Chinese Academy of SciencesChangshaChina Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation College of Life SciencesHunan Normal UniversityChangshaChina Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjinChina

Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.

关键词： Additional dosage Biological function Metabolic pathway Pig Valine

Two-Dimensional Materials for Highly Efficient and Stable Perovskite Solar Cells

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Nano-Micro Letters 2024年第10期16卷 176-212页

作者： Xiangqian Shen Xuesong Lin Yong Peng Yiqiang Zhang Fei Long Qifeng han Yanbo wang Liyuan han State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People's Republic of China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physical Science and TechnologyXinjiang UniversityUrumqi 830046People's Republic of China Special Division of Environmental and Energy Science College of Arts and SciencesKomaba Organization for Educational ExcellenceUniversity of TokyoTokyo 153-8902Japan State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People's Republic of China College of Chemistry Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001People's Republic of China Guangxi Key Laboratory of Optical and Electronic Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004People's Republic of China

Perovskite solar cells(PSCs)offer low costs and high power conversion ***,the lack of long-term stability,primarily stemming from the interfacial defects and the sus-ceptible metal electrodes,hinders their practical *** the past few years,two-dimensional(2D)materials(e.g.,graphene and its derivatives,transitional metal dichalcogenides,MXenes,and black phosphorus)have been identified as a promising solution to solving these problems because of their dangling bond-free surfaces,layer-dependent electronic band structures,tunable functional groups,and inherent ***,recent progress of 2D material toward efficient and stable PSCs is summarized,including its role as both interface materials and *** discuss their beneficial effects on perovskite growth,energy level alignment,defect passivation,as well as blocking external *** particular,the unique properties of 2D materials to form van der Waals heterojunction at the bottom interface are ***,perspectives on the further development of PSCs using 2D materials are provided,such as designing high-quality van der Waals heterojunction,enhancing the uniformity and coverage of 2D nanosheets,and developing new 2D materials-based electrodes.

关键词： Perovskite solar cells Two-dimensional materials Interface engineering Van der Waals heterojunction Electrodes