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Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses

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Nuclear Science and Techniques 2024年第3期35卷 228-236页

作者： Ting-Zhi Yan Shan Li School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)*** neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in *** defined the unified neutron skin thickness asΔRnp=^(1∕2) n−^(1∕2)p,which was negative for neutron-deficient *** unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling *** yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were *** results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact *** addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains.

关键词： Exotic nuclei Unified neutron skin thickness Yield ratios IQMD

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Numerical Investigation on Characteristics of Supercritical CO_(2)Heat Transfer in Vertical Circular Tubes with Circumferentially Half-Side Heating

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Journal of Thermal Science 2024年第5期33卷 1744-1756页

作者： ZHANG Yan ZHANG Xinyi YAN Chenshuai WU Wenhua GAO Erman School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The design of heat exchangers in the advanced supercritical power conversion system cannot be separated from the study of heat transfer ***-side heating mode is often encountered for solar receiver and supercritical ***,the characteristics of supercritical CO_(2)(sCO_(2))convection heat transfer in vertical tubes with circumferentially half-side heating was numerically investigated through the SST k-ωturbulent model which matches well with the experimental ***,heat transfer between sCO_(2)upflow and downflow was *** to film boiling heat transfer at subcritical pressure,numerical results were processed according to the supercritical pseudo-phase transition hypothesis,with liquid-like phase in the tube core region and vapor-like film in the region near the heated tube *** structure of two layers was demarcated by pseudo-critical temperature T_(pc).Therefore,sCO_(2)heat transfer was assessed according to double thermal resistances caused by vapor-like film near the wall and core liquid-like *** findings suggest that wall temperature for upflow is higher than that for downflow,which is attributed to larger thermal resistance in the fluid domain for upflow than that for *** difference guarantees the excellent heat transfer performance for downflow than *** is also further concluded that the formation of vapor-like film near the wall due to pseudo-phase transition plays a key role in dominating wall temperature and inducing heat transfer deterioration in half-side heating *** present contribution is significant to the design of supercritical heat exchanger under half-side heating mode.

关键词： supercritical CO_(2) pseudo-phase transition half-side heating thermal resistance flow direction

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Oxygenic iron clusters in ZSM-5 zeolite promote quantum sieving of gaseous hydrogen isotopes

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Science china Chemistry 2024年第4期67卷 1242-1249页

作者： Jingjing Zhang Yongyan Deng Dongxu Gai Yang Shi Xingwen Feng Peilong Li Yongtao An Xiaoqin Zou Institute of Materials China Academy of Engineering PhysicsMianyang 621907China Faculty of Chemistry Northeast Normal UniversityChangchun 130024China

Isotopic separation is of paramount importance for producing high-purity heavy hydrogen,yet the process remains hugely ***,we report on an Fe/ZSM-5 zeolite that was able to efficiently separate deuterium from protium via chemical quantum *** data showed that four types of Fe species were present in Fe/ZSM-5 and oligomeric Fe-O clusters in the zeolite pores were correlated directly with gas *** adsorption revealed that Fe-O species served as the main adsorption sites and interacted with D_(2) more strongly than with H_(2).D_(2)/H_(2)separation was exemplified using thermal desorption spectroscopy.D_(2)/H_(2) selectivity increased with Fe loading in Fe/ZSM-5 and a selectivity of 32.1 was obtained with an optimal loading of 7 wt%.The shift of desorption temperature supports the chemical affinity-based quantum sieving of D_(2)over H_(2).This study demonstrates an effective strategy for enhancing D_(2)/H_(2) separation and the high selectivity means that Fe/ZSM-5 has strong potential in hydrogen isotope separation.

关键词： iron zeolite hydrogen isotope gas separation quantum sieving thermal desorption

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Climate and Soil Geochemistry Influence the Soil Organic Carbon Content in Drylands of the Songliao Plain, northeast china

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Acta Geologica Sinica(English Edition) 2024年第5期98卷 1394-1403页

作者： LIU Kai DAI Huimin SONG Yunhong LIANG Shuai YANG Zhongfang School of Earth Sciences and Resources China University of Geosciences Key Laboratory of Black Soil Evolution and Ecological Effect Ministry of Natural Resources/Liaoning Province Shenyang Center of china geological Survey Northeast Geological S&T Innovation Center of China Geological Survey

The understanding of the spatial distribution of soil organic carbon(SOC) and its influencing factors is crucial for comprehending the global carbon cycle. However, the impact of soil geochemical and climatic conditions on SOC remains limited, particularly in dryland farming areas. In this study, we aimed to enhance the understanding of the factors influencing the distribution of SOC in the drylands of the Songliao Plain, northeast china. A dataset comprising 35,188 measured soil samples was used to map the SOC distribution in the region. Multiple linear regression(MLR) and random forest models(RFM) were employed to assess the importance of driving indicators for SOC. We also carried out partial correlation and path analyses to further investigate the relationship between climate and geochemistry. The SOC content in dryland soils of the Songliao Plain ranged from 0.05% to 11.63%, with a mean value of 1.47% ± 0.90%. There was a notable increasing trend in SOC content from the southwest to the northeast regions. The results of MLR and RFM revealed that temperature was the most critical factor, demonstrating a significant negative correlation with SOC content. Additionally, iron oxide was the most important soil geochemical indicator affecting SOC variability. Our research further suggested that climate may exert an indirect influence on SOC concentrations through its effect on geochemical properties of soil. These insights highlight the importance of considering both the direct and indirect impact of climate in predicting the SOC under future climate change.

关键词： climate change northeast china soil geochemistry soil organic carbon

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How Does Urban Shrinkage Affect Land Use Efficiency?A Case Study of Shrinking Cities in northeast china

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Chinese Geographical Science 2024年第1期34卷 34-51页

作者： XIE Mingke FENG Zhangxian SONG Yang GUAN Haoming WANG Shijun School of Geographical Sciences Northeast Normal UniversityChangchun130024China

The effect of urban shrinkage has gradually become a new ***,urban shrinkage may exert great influence on land use efficiency(LUE)through various urban subsystems,but there is currently limited research examining these *** the Super-SBM-Undesirable model and the Structural Equation Model(SEM),this study calculates the LUE of shrinking cities in northeast china and simulates the process of urban shrinkage affecting *** quantify the process of urban shrinkage affecting LUE,three mediation variables,namely the economy,public services,and innovation,are used as latent variables to apply *** results show that urban shrinkage will affect LUE through a direct path and indirect *** the direct path,urban shrinkage leads to an improvement in *** the indirect paths,the economy and innovation will transmit the negative effect of urban shrinkage on LUE,while public services will reverse this *** important contribution of this study is that it quantifies the paths of urban shrinkage affecting LUE,thereby expanding the understanding of urban shrinkage effect and laying a foundation for the sustainable development of shrinking cities.

关键词： urban shrinkage land use efficiency Super-SBM-Undesirable model Structural Equation Model(SEM) northeast china

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BACNN: Multi-scale feature fusion-based bilinear attention convolutional neural network for wood NIR classification

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Journal of Forestry Research 2024年第4期35卷 202-214页

作者： Zihao Wan Hong Yang Jipan Xu Hongbo Mu Dawei Qi College of Science Northeast Forestry UniversityHarbin 150040People’s Republic of China

Effective development and utilization of wood resources is *** modification research has become an integral dimension of wood science research,however,the similarities between modified wood and original wood render it challenging for accurate identification and classification using conventional image classification ***,the development of efficient and accurate wood classification techniques is *** paper presents a one-dimensional,convolutional neural network(i.e.,BACNN)that combines near-infrared spectroscopy and deep learning techniques to classify poplar,tung,and balsa woods,and PVA,nano-silica-sol and PVA-nano silica sol modified woods of *** results show that BACNN achieves an accuracy of 99.3%on the test set,higher than the 52.9%of the BP neural network and 98.7%of Support Vector Machine compared with traditional machine learning methods and deep learning based methods;it is also higher than the 97.6%of LeNet,98.7%of AlexNet and 99.1%of ***,the classification method proposed offers potential applications in wood classification,especially with homogeneous modified wood,and it also provides a basis for subsequent wood properties studies.

关键词： Wood classification Near infrared spectroscopy Bilinear network SE module Anti-noise algorithm

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Variation Characteristics of Root Traits of Different Alfalfa Cultivars under Saline-Alkaline Stress and their Relationship with Soil Environmental Factors

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 29-43页

作者： Tian-Jiao Wei Guang Li Yan-Ru Cui Jiao Xie Xing-Ai Gao Xing Teng Xin-Ying Zhao Fa-Chun Guan Zheng-Wei Liang northeast Agricultural Research Center of china Jilin Academy of Agricultural SciencesChangchun130033China northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130102China

Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of *** is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil *** this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment *** the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried *** results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline *** was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline *** number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control *** ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(p<0.05).The root fresh weight(RFW)and dry weight(RDW),root length(RL),RV and RT of alfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase ac

关键词： Saline-alkaline stress alfalfa root traits soil environmental factors correlation analysis

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Source Enrichment Control on the Scale of Magmatic-Hydrothermal W-Sn Mineralization:Insights from Triassic and Jurassic Magma Reservoirs in the Continental Crust,Xitian,South china

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 132-149页

作者： GUO Chunli Simon AWILDE Coralie SIEGEL CHEN Zhenyu WU Shichong MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100094China School of Earth and Planetary Sciences Curtin UniversityPerth 6845Australia Discovery Program Mineral ResourcesCommonwealth Scientific and Industrial Research OrganisationAustralian Resources Research CentrePerth 6151Australia No.416 geological Group Hunan Bureau of Mineral Exploration and DevelopmentZhuzhouHunan 412007China

There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn *** one is more important is widely debated and may need to be determined for each individual *** Xitian granite batholith located in South china is a natural laboratory for investigating the above *** consists essentially of two separate components,formed in the Triassic at ca.226 Ma and Jurassic at ca.152 Ma,*** Triassic and Jurassic rocks are both composed of porphyritic and fine-grained *** latter resulted from highlydifferentiated porphyritic ones but they have similar textural characteristics and mineral assemblages,indicating that they reached a similar degree of crystal *** both fine-grained phases are highly differentiated with elevated rare metal contents,economic W–Sn mineralization is rare in the Triassic granitoids and this can be attributed to less fertile source materials than their Jurassic counterparts,with a slightly more enriched isotopic signature and whole-rockεNd(226 Ma)of−10.4 to−9.2(2σ=0.2)compared withεNd(152 Ma)of−9.2 to−8.2(2σ=0.2)for the Jurassic *** initial W-Sn enrichment was derived from the metasedimentary rocks and strongly enhanced by reworking of the continental crust,culminating in the Jurassic.

关键词： W-Sn mineralization magma reservoir geometry crystal fractionation Xitian Triassic-Jurassic granitic batholith Nanling Range South china

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Comprehensive evaluation of multi-energy complementary ecosystem based on improved multicriteria decision-making method

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Clean Energy 2024年第1期8卷 226-236页

作者： Huang Shuyi Zou Xuetong Liang Huaguang Chen Jie Shenzhen Power Supply bureau China Southern Power GridShenzhen 518048China

The multi-energy complementary ecosystem is an important form of the modern energy ***,standardized evaluation criteria and the corresponding method framework have not yet been formed,resulting in unclear standards and irregular processes of its *** cope with this issue,a novel comprehensive evaluation framework for multi-energy complementary ecosystems is proposed in this ***,a 5D comprehensive evaluation criteria system,including environment,economy,technology,safety and systematicness,is ***,a novel multicriteria decision-making model integrating an analytic network process,entropy and preference-ranking organization method for enrichment evaluation under an intuitional fuzzy environment is ***,four practical cases are used for model testing and empirical *** results of the research show that the unit cost of the energy supply and the internal rate of return indexes have the highest weights of 0.142 and 0.010,*** means that they are the focus in the construction of a multi-energy complementary *** net flows of four cases are 0.015,0.123,-0.132 and-0.005,indicating that cases with a variety of energy supply forms and using intelligent management and control platforms to achieve cold,heat and electrical coupling have more advantages.

关键词： multi-energy complementary ecosystem comprehensive evaluation intuitionistic fuzzy multicriteria decision-making

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An Energy Trading Method Based on Alliance Blockchain and Multi-Signature

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Computers, Materials & Continua 2024年第2期78卷 1611-1629页

作者： Hongliang Tian Jiaming Wang College of Electrical Engineering Northeast Electric Power UniversityJilin132012China

Blockchain,known for its secure encrypted ledger,has garnered attention in financial and data transfer realms,including the field of energy ***,the decentralized nature and identity anonymity of user nodes raise uncertainties in energy *** broadcast consensus authentication slows transaction speeds,and frequent single-point transactions in multi-node settings pose key exposure risks without protective measures during user *** address these,an alliance blockchain scheme is proposed,reducing the resource-intensive identity verification among *** integrates multi-signature functionality to fortify user resources and transac-tion security.A novel multi-signature process within this framework involves neutral nodes established through central *** neutral nodes participate in multi-signature’s signing and verification,ensuring user identity and transaction content *** interactions among user nodes enhances transaction efficiency by minimizing communication overhead during verification and consensus *** assessments on reliability and operational speed highlight superior security performance,resilient against conventional attack *** shows that compared to traditional solutions,this scheme has advantages in terms of running *** conclusion,the alliance blockchain framework introduces a novel approach to tackle blockchain’s limitations in energy *** integrated multi-signature process,involving neutral nodes,significantly enhances security and *** scheme’s efficiency,validated through analytical assessments and simulations,indicates robustness against security threats and improved transactional *** research underscores the potential for improved security and efficiency in blockchain-enabled energy trading systems.

关键词： Alliance blockchain multi-signature energy trading security performance transaction efficiency

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