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Regulating the oxidation state of Pd to enhance the selective hydrogenation for 5-hydroxymethylfurfural

Chinese Journal of Chemical Engineering 2024年第8期72卷 60-68页

作者： Xin Li Yue Ma Xuning Wang Jianguo Wu Dong Cao Daojian Cheng State Key Laboratory of Organic-Inorganic Composites and College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

The highly selective hydrogenation of 5-hydroxymethylfurfural to 2,5-dihydroxymethylfuran is an important reaction in the field of biomass hydrogenation,because it is a bridge between biomass resources and chemical ***,we precisely constructed carbon nitride supported Pd-based catalysts by a simple impregnation-reduction *** changing the reduction temperature,catalysts with different oxidation state could be precisely ***,the important correlation between the ratio of Pd^(0)/Pd^(2+)and catalytic activity is revealed during the selective hydrogenation of *** Pd/g—C_(3)N_(4)—300 catalyst with a Pd^(0)/Pd^(2+)ratio of 3/2 showed the highest catalytic activity,which could get 96.9%5-hydroxymethylfurfural conversion and 90.3%2,5-dihydroxymethylfuran *** density functional theory calculation revealed that the synergistic effect between Pd0and Pd2+in Pd/g—C_(3)N_(4)—300 system could boost the adsorption of the substrate and the dissociation of *** this work,we highlight the important correlation between metal oxidation state and catalytic activity,which provides valuable insights for the rational design of precious metal catalysts for hydrogenation reactions.

关键词： Pd/g-C_(3)N_(4) Selective hydrogenation 5-hydroxymethylfurfural 2,5-dihydroxymethylfuran Oxidation state

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Fine mapping and characterization of a major QTL for grain length,***-2D.1,that has pleiotropic effects in synthetic allohexaploid wheat

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Journal of Integrative Agriculture 2024年第9期23卷 2911-2922页

作者： Mingming Wang Jia Geng Zhe Zhang Zihan Zhang Lingfeng Miao Tian Ma Jiewen Xing Baoyun Li Qixin Sun Yufeng Zhang Zhongfu Ni Frontiers Science Center for Molecular Design Breeding/Key Laboratory of Crop Heterosis and Utilization Ministry of Education/Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100193China National Plant Gene Research Centre Beijing 100193China

Grain size is one of the determinants of grain yield,and identifying the genetic loci that control grain size will be helpful for increasing grain *** our previous study,a quantitative trait locus(QTL)for grain length(GL),***-2D.1,was identified from an F2 population developed from the cross between the natural(TAA10)and synthetic(XX329)allohexaploid *** the present study,we mainly fine mapped and validated its genetic *** this end,multiple near-isogenic lines(NILs)were obtained through marker-assisted selection with TAA10 as the recurrent *** secondary populations derived from 25 heterozygous recombinants were used for fine mapping of ***-2D.1,and the allele from XX329 significantly increased GL,thousand-grain weight(TGW),total spikelet number per spike(TSN)and spike compactness(SC).Using NILs for XX329(2D+)and TAA10(2D−),we determined the genetic and pleiotropic effects of *** target sequences were aligned with the wheat reference genome RefSeq v2.1 and spanned an~0.9 Mb genomic ***2D03G0114900(ortholog of Os03g0594700)was predicted as the candidate gene based on whole-genome re-sequencing and expression *** summary,the map-based cloning of ***-2D.1 will be useful for improving grain weight with enhanced GL and TSN.

关键词： grain length total spikelet number per spike spike compactness near-isogenic lines QTL wheat

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Study on the oxidation mechanism of Al-SiC composite at elevated temperature

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2077-2087页

作者： Jishuo Han Yong Li Chenhong Ma Qingyao Zheng Xiuhua Zhang Xiaofang Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Vesuvius Advanced Ceramics(China)Co. LtdSuzhou 215000China

Resin-bonded Al-SiC composite was sintered at 1100,1300,and 1500℃ in the air,the oxidation mechanism was *** reaction models were also *** oxidation resistance of the Al-SiC composite was significantly enhanced with temperature *** in the exterior of the composite was partially oxidized slightly,while the transformation of metastable Al_(4)C_(3) to stable Al_(4)SiC_(4) existed in the *** 1100℃,Al in the interior reacted with residual C to form Al_(4)C_(3).With increasing to 1300℃,high temperature and low oxygen partial pressure lead to active oxidation of SiC,and internal gas composition transforms to Al_(2)O(g)+CO(g)+SiO(g)as the reaction *** Al_(4)C_(3) is formed,CO(g)and SiO(g)are continuously deposited on its surface,transforming to Al_(4)SiC_(4).At 1500℃,a dense layer consisting of SiC and Al_(4)SiC_(4) whiskers is formed which cuts off the diffusion channel of *** active oxidation of SiC is accelerated,enabling more gas to participate in the synthesis of Al_(4)SiC_(4),eventually forming hexagonal lamellar Al_(4)SiC_(4) with mutual accumulation between SiC *** Al enhances the oxidation resistance of *** addition,the in situ generated non-oxide is uniformly dispersed on a micro-scale and bonds SiC stably.

关键词： Al-SiC composite kiln furniture Al_(4)SiC_(4) Al_(4)C_(3) oxidation mechanism

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Low Stress TSV Arrays for High-Density Interconnection

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Engineering 2024年第7期38卷 201-208页

作者： Binbin Jiao Jingping Qiao Shiqi Jia Ruiwen Liu Xueyong Wei Shichang Yun Yanmei Kong Yuxin Ye Xiangbin Du Lihang Yu Bo Cong Institute of Microelectronics Chinese Academy of SciencesBeijing 100000China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100000China State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China

In three-dimensional(3D)stacking,the thermal stress of through-silicon via(TSV)has a significant influence on chip performance and reliability,and this problem is exacerbated in high-density TSV *** this study,a novel hollow tungsten TSV(W-TSV)is presented and *** hollow structure provides space for the release of thermal *** results showed that the hollow W-TSV structure can release 60.3%of thermal stress within the top 2 lm from the surface,and thermal stress can be decreased to less than 20 MPa in the radial area of 3 *** ultra-high-density(1600 TSV∙mm2)TSV array with a size of 640×512,a pitch of 25 lm,and an aspect ratio of 20.3 was fabricated,and the test results demonstrated that the proposed TSV has excellent electrical and reliability *** average resistance of the TSV was 1.21 *** leakage current was 643 pA and the breakdown voltage was greater than 100 *** resistance change is less than 2%after 100 temperature cycles from40 to 125℃.Raman spectroscopy showed that the maximum stress on the wafer surface caused by the hollow W-TSV was 31.02 MPa,which means that there was no keep-out zone(KOZ)caused by the TSV *** results indicate that this structure has great potential for applications in large-array photodetectors and 3D integrated circuits.

关键词： Thermal stress Through-silicon via(TSV)High-density integration

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Simulation of gas-solid flow characteristics of the circulating fluidized bed boiler under pure-oxygen combustion conditions

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Chinese Journal of Chemical Engineering 2024年第6期70卷 9-19页

作者： Kaixuan Gao Xiwei Ke Bingjun Du Zhenchuan Wang Yan Jin Zhong Huang Yanhong Li Xuemin Liu Key Laboratory of Special Equipment Safety and Energy-Saving for State Market Regulation China Special Equipment Inspection&Research InstituteBeijing 100029China Department of Energy and Power Engineering Tsinghua UniversityBeijing 100084China School of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China

Under the pressure of carbon neutrality,many carbon capture,utilization and storage technologies have witnessed rapid development in the recent years,including oxy-fuel combustion(OFC)***,the conventional OFC technology usually depends on the flue gas recirculation system,which faces significant investment,high energy consumption,and potential low-temperature corrosion *** these deficiencies,the direct utilization of pure oxygen to achieve particle fluidization and fuel combustion may reduce the overall energy consumption and CO_(2)-capture *** this paper,the fundamental structure of a self-designed 130 t·h^(-1) pure-oxygen combustion circulating fluidized bed(CFB)boiler was provided,and the computational particle fluid dynamics method was used to analyze the gas-solid flow characteristics of this new-concept boiler under different working *** results indicate that through the careful selection of design or operational parameters,such as average bed-material size and fluidization velocity,the pure-oxygen combustion CFB system can maintain the ideal fluidization state,namely significant internal and external particle ***,the contraction section of the boiler leads to the particle backflow in the lower furnace,resulting in the particle suspension concentration near the wall region being higher than that in the center ***,the upper furnace still retains the classic core-annulus flow *** addition to increasing solid circulation rate by reducing the average bed-material size,altering primary gas ratio and bed inventory can also exert varying degrees of influence on the gas-solid flow characteristics of the pure-oxygen combustion CFB boiler.

关键词： Circulating fluidized bed Pure-oxygen combustion Gas-solid flow characteristics Simulation CO_(2)capture

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High-efficiency prediction method for helicopter global/ground noise based on near-field acoustic holography

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Chinese Journal of Aeronautics 2024年第7期37卷 271-284页

作者： Mengxue SHAO Yang LU Xice XU Jiaxin LU National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Noise reduction program design is an effective approach that relies on efficient noise prediction for reducing ground noise during *** existing noise prediction methods have the limitations of being computationally expensive or only applicable to *** this paper,a High-Efficiency Prediction Method(HEPM)for helicopter global/ground noise based on near-field acoustic holography is *** HEPM can predict the global noise based on acoustic modal analysis and has the advantages of high prediction accuracy and low time *** process is given as follows:firstly,the rotor noise on the holographic surface in the specified flight is obtained by simulations or ***,the global noise model,which maps time-domain noise to acoustic modes,is established based on near-field acoustic holography and Fourier acoustic analysis ***,combined with acoustic modal amplitude,the model established enables efficiently predicting the global/ground noise in the corresponding flight *** verify the accuracy of the prediction method,a simulation study is conducted in hovering and forward flight states using a model helicopter with a 2-meter rotor and Rotor Body Interaction(ROBIN)*** comparison of HEPM with numerical results shows that the average prediction errors of the global and ground noise are less than 0.3 dB and 0.2 dB,*** a region containing 100000 observers,the computation time of the HEPM is only one-fifth of that of the acoustic hemisphere method,demonstrating the rapidity of the proposed method.

关键词： Helicopter Rotor noise prediction Noise abatement procedure design Acoustic modal analysis Near-field acoustic holography

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Optimal Planning of Hybrid AC/DC Low-voltage Distribution Networks Considering DC Conversion of Three-phase Four-wire Low-voltage AC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 141-153页

作者： Bo Zhang Lu Zhang Wei Tang Gen Li Chen Wang the College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China the Electric Energy Group Department of Engineering TechnologyTechnical University of Denmark(DTU)2750 BallerupDenmark the Power Distribution Technology Center State Grid Beijing Electric Power Research InstituteBeijing 100075China

The increasing integration of distributed household photovoltaics(PVs)and electric vehicles(EVs)may further ag gravate voltage violations and unbalance of low-voltage distribu tion networks(LVDNs).DC distribution networks can increase the accommodation of PVs and EVs and mitigate mutilple pow er quality problems by the flexible power regulation capability of voltage source *** paper proposes schemes to es tablish hybrid AC/DC LVDNs considering the conversion of the existing three-phase four-wire low-voltage AC systems to DC op *** characteristics and DC conversion constraints of typical LVDNs are *** addition,converter configura tions for typical LVDNs are proposed based on the three-phase four-wire characteristics and quantitative analysis of various DC ***,an optimal planning method of hybrid AC/DC LVDNs is proposed,which is modeled as a bi-level programming model considering the annual investments and three-phase *** are conducted to verify the effectiveness of the proposed optimal planning *** ulation results show that the proposed optimal planning method can increase the integration of PVs while simultaneously reduc ing issues related to voltage violation and unbalance.

关键词： Optimal planning low-voltage distribution net work three-phase unbalance DC conversion

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Prenatal amoxicillin exposure induces developmental toxicity in fetal mice and its characteristics

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Journal of Environmental Sciences 2024年第3期137卷 287-301页

作者： Yongguo Dai Yu Peng Wen Hu Yi Liu Hui Wang Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Department of Pharmacy Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Amoxicillin,a widely used antibiotic in human and veterinary pharmaceuticals,is now considered as an“emerging contaminant”because it exists widespreadly in the environment and brings a series of adverse ***,systematic studies about the developmental toxicity of amoxicillin are still *** explored the potential effects of amoxicillin exposure on pregnancy outcomes,maternal/fetal serum phenotypes,and fetal multiple organ development in mice,at different doses(75,150,300 mg/(kg·day))during late-pregnancy,or at a dose of 300 mg/(kg·day)during different stages(mid-/latepregnancy)and courses(single-/multi-course).Results showed that prenatal amoxicillin exposure(PAmE)had no significant infuence on the body weights of dams,but it could inhibit the physical development and reduce the survival rate of fetuses,especially during the ***,PAmE altered multiple maternal/fetal serum phenotypes,especially in *** multi-organ function results showed that PAmE inhibited testicular/adrenal steroid synthesis,long bone/cartilage and hippocampal development,and enhanced ovarian steroid synthesis and hepatic glycogenesis/lipogenesis,and the order of severity might be gonad(testis,ovary)>liver>*** analysis found that PAmE-induced multiorgan developmental and functional alterations had differences in stages,courses and fetal gender,and the most obvious changes might be in high-dose,late-pregnancy and multicourse,but there was no typical rule of a dose-response *** conclusion,this study confirmed that PAmE could cause abnormal development and multi-organ function alterations,which deepens our understanding of the risk of PAmE and provides an experimental basis for further exploration of the long-term harm.

关键词： Amoxicillin Prenatal exposure Fetal development Organ function developmental toxicity

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Paving the way toward soil safety and health:current status,challenges,and potential solutions

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 63-73页

作者： Chiheng Chu Lizhong Zhu College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon ***,the health of soil faces global threats from human activities,particularly widespread contamination by industrial *** physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional *** solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale ***,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of ***,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring *** the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

关键词： Soil safety and health Source emission reduction Process monitoring and simulation Green remediation technology Soil health management

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research progress in CALPHAD assisted metal additive manufacturing

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china Foundry 2024年第4期21卷 295-310页

作者： Ya-qing Hou Xiao-qun Li Wei-dong Cai Qing Chen Wei-ce Gao Du-peng He Xue-hui Chen Hang Su China Iron&Steel Research Institute Group Beijing 100081China Thermo-Calc Software AB SolnaSE-169Sweden KTH Royal Institute of Technology StockholmSE-100Sweden Central Iron and Steel Research Institute Beijing 100081China

Metal additive manufacturing(MAM)technology has experienced rapid development in recent *** both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology based on high energy sources has become a key factor influencing the future development of *** calculation of phase diagrams(CALPHAD)is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple *** combining with the element mobility data and non-equilibrium phase transition model,it has been widely used in the analysis of traditional metal *** development of CALPHAD application technology for MAM is focused on the compositional design of printable materials,the reduction of metallurgical imperfections,and the control of microstructural *** endeavor carries considerable theoretical and practical *** paper summarizes the important achievements of CALPHAD in additive manufacturing(AM)technology in recent years,including material design,process parameter optimization,microstructure evolution simulation,and properties ***,the limitations of applying CALPHAD technology to MAM technology are discussed,along with prospective research directions.

关键词： metal additive manufacturing CALPHAD integrated computational material engineering powder bed fusion material design microstructure simulation

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