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基于决策树算法的焦炭CSR和CRI性能预测模型
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作者 刘晓航 史先菊 +3 位作者 许德明 贺铸 李光强 王强 《烧结球团》 北大核心 2025年第4期151-160,共10页
焦炭的CSR(焦炭反应后强度)和CRI(焦炭反应性指数)性能指标对提高高炉冶炼效率、降低生产成本和促进绿色生产等起到至关重要的作用。传统依赖人工经验调控存在响应慢、误差大等问题,难以实现对CSR和CRI的精准实时预测。本文基于焦炭的... 焦炭的CSR(焦炭反应后强度)和CRI(焦炭反应性指数)性能指标对提高高炉冶炼效率、降低生产成本和促进绿色生产等起到至关重要的作用。传统依赖人工经验调控存在响应慢、误差大等问题,难以实现对CSR和CRI的精准实时预测。本文基于焦炭的灰分、挥发分、硫分和固定碳等基础属性,采用大数据拟合与机器学习技术,构建预测CSR和CRI的决策树算法;通过网格搜索结合交叉验证来优化超参数,筛选出最优的决策树,并利用特征相关热图、特征相关性及SHAP值解释模型的预测机制。结果表明:当树深度为19、随机种子数为44时,CSR模型的预测效果最佳,精度达98.543%;当树深度为18、随机种子数为75时,CSR模型的预测效果最佳,精度达96.825%;现场测试结果显示,封装后在线实时预测软件的单次预测时间仅为0.1~0.3 s,软件具备良好的实时性与稳定性。本文开发的预测系统能有效支持高炉生产中焦炭的质量决策,显著提升预测效率与准确性,推动炼铁过程向智能化、绿色化和高效化发展。 展开更多
关键词 高炉炼铁 焦炭反应后强度 焦炭反应性指数 机器学习 决策树算法
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相近CRI及CSR的同系焦炭不可替换性Qisunny法分析
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作者 李哲熙 李廷乐 +4 位作者 黄浚宸 汪琦 杨松陶 孙长余 朱亚明 《煤炭转化》 北大核心 2025年第6期102-111,共10页
CRI&CSR一直是评价焦炭最重要的指标之一。目前为了确保高炉生产的连续稳定,钢厂均选用热性能指标CRI&CSR相近的同系焦炭投入生产,但此举经常会引起高炉炉况的波动,核心问题在于同系焦炭是否可以相互替换,而可替换性取决于同系... CRI&CSR一直是评价焦炭最重要的指标之一。目前为了确保高炉生产的连续稳定,钢厂均选用热性能指标CRI&CSR相近的同系焦炭投入生产,但此举经常会引起高炉炉况的波动,核心问题在于同系焦炭是否可以相互替换,而可替换性取决于同系焦炭在高炉内的作用是否相近,冶炼效果是否相同。为了解决这一问题,本研究选取3种CRI&CSR数值相近的同系焦炭与同1种配矿进行了模拟高炉情况的矿焦耦合实验(Qisunny实验)。主要针对同系焦炭的熔损劣化行为、还原作用和热作用三个方面,全方位解析了3种同系焦炭的冶炼效果。研究结果表明:在矿焦耦合实验过程中,同系焦炭的熔损劣化行为并不相同,对矿石的间接还原和直接还原过程均造成不同程度的影响。热力学分析表明,同系焦炭的热流密度变化趋势并不相同,导致其对高炉热交换的影响存在显著差异。因此,同系焦炭并不一定意味着其具有相近的冶炼效果,即CRI&CSR数值相近的焦炭并不一定可相互替换。 展开更多
关键词 高炉 焦炭 cri&CSR 焦炭冶炼 热力学
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人工快速渗滤系统(CRI)在江西农村污水处理中的应用及效果分析
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作者 刘剑 苏甜 +2 位作者 刘方平 姜成名 邹玉稿 《江西水利科技》 2025年第5期377-381,共5页
针对江西省农村地区生活污水排放分散、水质变化显著等特点,本示范工程采用人工快速渗滤系统(CRI)技术进行处理。采用降雨事件驱动采样法对运行期的进出水水质进行监测,并分析该技术对农村生活污水的处理净化效果。监测结果表明:CRI系... 针对江西省农村地区生活污水排放分散、水质变化显著等特点,本示范工程采用人工快速渗滤系统(CRI)技术进行处理。采用降雨事件驱动采样法对运行期的进出水水质进行监测,并分析该技术对农村生活污水的处理净化效果。监测结果表明:CRI系统对氨氮的去除率为35.7%~72.2%,总氮的去除率为56.5%~79.6%,总磷去除率为84.1%~93.5%,泥沙去除率为72.0%~89.4%。经处理后的出水主要指标均符合《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级A标准要求。 展开更多
关键词 人工快速渗滤系统(cri) 硝化 去除率 示范工程
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基于CRI混合式教学模式金融学课程教学改革研究
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作者 柯丁琪 《老字号品牌营销》 2025年第11期203-205,共3页
CRI混合式教学模式整合线上资源、线下互动与个性化指导,为金融学课程教学改革提供系统性解决方案。本文基于数字经济时代金融人才培养需求,探索CRI混合式教学模式在金融学课程中的创新应用路径,提出“三阶联动”改革框架,即课前依托线... CRI混合式教学模式整合线上资源、线下互动与个性化指导,为金融学课程教学改革提供系统性解决方案。本文基于数字经济时代金融人才培养需求,探索CRI混合式教学模式在金融学课程中的创新应用路径,提出“三阶联动”改革框架,即课前依托线上平台推送行业前沿案例,引导学生自主构建知识框架,课中线下研讨深化理论认知,借助模拟交易、沙盘推演等实践工具强化金融实务能力,课后延伸线上拓展学习与线下研究任务,形成“理论学习—实践验证—创新应用”的闭环学习生态,以期为培养具有数字化思维、实践创新能力的高素质金融人才提供方法论支撑。 展开更多
关键词 cri混合式教学模式 金融学 课程教学 改革研究
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Surrogate-based buckling analysis and optimization of composite plates modeled using a novel nonlinear function to describe fiber orientation
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作者 Yang LIU Xinjun LIU 《Chinese Journal of Aeronautics》 2025年第5期458-472,共15页
The stiffness properties of variable stiffness(VS) composite plates can be controlled by manipulating the variation in the fiber angle, thereby significantly improving their buckling properties. Nonlinear fiber paths ... The stiffness properties of variable stiffness(VS) composite plates can be controlled by manipulating the variation in the fiber angle, thereby significantly improving their buckling properties. Nonlinear fiber paths have attracted attention in the field of composites due to their large design space. The major challenge in adopting nonlinear fiber paths is obtaining a fiber path function within the design space that is easily computable and efficiently yields the highest buckling load of a VS plate. In this investigation, an innovative nonlinear function was proposed to describe the fiber orientation by integrating a center fiber angle into the conventional linear function. The parameters of the nonlinear function can directly represent the fiber angles at a fixed position. This novel approach has promising potential for improving the optimal efficiency of fiber paths because the linear and nonlinear functions are simplified with two identical path parameters. Furthermore, a multilevel optimization method was developed by combining finite element analysis(FEA) with an adaptive radial basis function(RBF) surrogate model, and it was found that the number of FEA cases could be reduced by iteratively inheriting training points. The integration of this nonlinear function with a surrogate model is a significant advancement in the structural optimization of composites. Subsequently, the optimal linear and nonlinear fiber paths were computed to maximize the buckling load of VS plates. The FEA results show that the computational efficiency was greatly improved by the proposed nonlinear function and optimization method. The buckling resistance could be enhanced by the nonlinear fiber path, and the reinforcement mechanism was the redistribution and reduction of in-plane compressive stress. 展开更多
关键词 COMPOSITES Variable stiffness Curvilinear fiber BUCKLING OPTIMIZATION
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一类复对称线性系统的不平衡CRI迭代方法
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作者 罗漪清 《应用数学进展》 2025年第3期357-363,共7页
基于实部与虚部组合(CRI)迭代方法,提出了一种不平衡CRI (LCRI)迭代方法,用于求解复对称半正定线性系统。理论上利用谱理论分析了LCRI方法的收敛性,并给出了拟最优参数的表达式,数值上进一步验证了新方法的高效性。Based on the combina... 基于实部与虚部组合(CRI)迭代方法,提出了一种不平衡CRI (LCRI)迭代方法,用于求解复对称半正定线性系统。理论上利用谱理论分析了LCRI方法的收敛性,并给出了拟最优参数的表达式,数值上进一步验证了新方法的高效性。Based on the combination of real and imaginary parts (CRI) iteration method, a lopsided CRI (LCRI) iteration method is proposed for solving complex symmetric positive semi-definite linear systems. By using the spectral theory, we not only analyze the convergence property of the LCRI method, but also obtain the quasi-optimal parameter expression. The efficiency of the new method is further verified numerically. 展开更多
关键词 复对称矩阵 cri迭代方法 不平衡分裂迭代 收敛性分析 拟最优参数
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Advances in Crack Formation Mechanisms,Evaluation Models,and Compositional Strategies for Additively Manufactured Nickel-Based Superalloys
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作者 Huabo Wu Jialiao Zhou +4 位作者 Lan Huang Zi Wang Liming Tan Jin Lv Feng Liu 《Computer Modeling in Engineering & Sciences》 2025年第6期2675-2709,共35页
Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms... Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms in AM nickel-based superalloys,emphasizing methodologies to evaluate crack sensitivity and compositional design strategies to mitigate defects.Key crack types—solidification,liquation,solid-state,stress corrosion,fatigue,and creep-fatigue cracks—are analyzed,with focus on formation mechanisms driven by thermal gradients,solute segregation,and microstructural heterogeneities.Evaluation frameworks such as the Rappaz-Drezet-Gremaud(RDG)criterion,Solidification Cracking Index(SCI),and Strain Age Cracking(SAC)index are reviewed for predicting crack susceptibility through integration of thermodynamic parameters,solidification kinetics,and mechanical properties.Alloy compositional design strategies are presented,including optimization of strengthening elements(Al,Ti),grain boundary modifiers(B,Zr,Re),and impurity control(C,O),which suppress crack initiation and propagation via microstructure refinement and enhanced high-temperature resistance.Computational approaches,such as thermodynamically assisted design,high-throughput experimentation,and machine learning,are highlighted for decoding complex composition-structure-property relationships.Challenges in modeling multi-scale defect interactions and developing unified frameworks for manufacturing-and service-induced cracks are outlined.This review underscores the necessity of integrated computational-experimental strategies to advance reliable AM of nickel-based superalloys,providing insights for defect prediction,alloy optimization,and process control. 展开更多
关键词 Additive manufacturing nickel-based superalloys CRACKING failure mechanism composition design
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Iron-Based Metal Matrix Composite:A Critical Review on the Microstructural Design,Fabrication Processes,and Mechanical Properties
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作者 Sai Chen Shuangjie Chu Bo Mao 《Acta Metallurgica Sinica(English Letters)》 2025年第1期1-44,共44页
Iron-based metal matrix composites(IMMCs)have attracted significant research attention due to their high specific stiffness and strength,making them potentially suitable for various engineering applications.Microstruc... Iron-based metal matrix composites(IMMCs)have attracted significant research attention due to their high specific stiffness and strength,making them potentially suitable for various engineering applications.Microstructural design,including the selection of reinforcement and matrix phases,the reinforcement volume fraction,and the interface issues are essential factors determining the engineering performance of IMMCs.A variety of fabrication methods have been developed to manufacture IMMCs in recent years.This paper reviews the recent advances and development of IMMCs with particular focus on microstructure design,fabrication methods,and their engineering performance.The microstructure design issues of IMMC are firstly discussed,including the reinforcement and matrix phase selection criteria,interface geometry and characteristics,and the bonding mechanism.The fabrication methods,including liquid state,solid state,and gas-mixing processing are comprehensively reviewed and compared.The engineering performance of IMMCs in terms of elastic modulus,hardness and wear resistance,tensile and fracture behavior is reviewed.Finally,the current challenges of the IMMCs are highlighted,followed by the discussion and outlook of the future research directions of IMMCs. 展开更多
关键词 Iron-based metal matrix composites MICROSTRUCTURE Fabrication methods Mechanical properties
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基于AHP-CRITIC法结合Box-Behnken设计-响应面法优选盐麸泽泻炮制工艺及药效研究 被引量:2
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作者 刘绍姜 钟凌云 +3 位作者 张弘弢 孙伟 张琬珑 秦月 《中草药》 北大核心 2025年第8期2773-2785,共13页
目的优选盐麸泽泻Alismatis Rhizoma的炮制工艺,并探究其对脂多糖诱导的小鼠小肠炎症的改善作用及其机制。方法以外观性状、醇溶性浸出物含量、23-乙酰泽泻醇B、23-乙酰泽泻醇C、24-乙酰泽泻醇A和泽泻醇B作为评价指标,对炮制过程中盐水... 目的优选盐麸泽泻Alismatis Rhizoma的炮制工艺,并探究其对脂多糖诱导的小鼠小肠炎症的改善作用及其机制。方法以外观性状、醇溶性浸出物含量、23-乙酰泽泻醇B、23-乙酰泽泻醇C、24-乙酰泽泻醇A和泽泻醇B作为评价指标,对炮制过程中盐水用量、麦麸用量、炒制时间和炒制温度进行考察,通过层次分析(analytic hierarchy process,AHP)-CRITIC(criteria importance though intercrieria correlation)复合加权法确定各评价指标的权重系数,联合单因素实验与Box-Behnken设计-响应面法(Box-Behnken design-response surface method,BBD-RSM)确定盐麸泽泻炮制工艺的最佳参数。基于优选工艺制备样品后,通过ip脂多糖建立小鼠小肠炎症模型,系统评价盐麸泽泻对小鼠的行为学特征与体质量动态变化、血液指标的影响、小肠组织病理学改变、回肠组织中肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-1β(interleukin-1β,IL-1β)、IL-6的释放水平以及组织中磷脂酰肌醇3激酶(phosphatidylinositol 3-kinase,PI3K)、蛋白激酶B(protein kinase B,Akt)、磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、磷酸化核因子κB抑制蛋白(phosphorylated inhibitor of nuclear factor kappa-B,p-IκB)和核因子κB p65亚基(nuclear factor kappa-B p65 subunit,NF-κB p65)蛋白质的表达水平。结果盐麸泽泻最佳炮制工艺参数:每100克泽泻饮片用15%盐水溶液闷润,晾干后与50 g麦麸在160℃炒制3 min。药效实验结果表明,盐麸泽泻水煎液可显著减轻脂多糖ip引起的小鼠体质量下降,血液指标的异常,回肠组织的损伤、炎症因子(TNF-α、IL-6、IL-1β)浓度升高以及组织中PI3K、p-Akt/Akt、p-Akt、p-IκB和NF-κB p65蛋白的表达水平上升。结论优选出的盐麸泽泻工艺操作简便,稳定可行,按照此工艺制备的盐麸泽泻,可有效改善脂多糖诱导的小鼠小肠炎症,其作用机制可能与PI3K-Akt/NF-κB通路有关。 展开更多
关键词 盐麸泽泻 炮制工艺 AHP-criTI复合加权法 响应面 脂多糖 小肠炎
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Wind Turbine Composite Blades:A Critical Review of Aeroelastic Modeling and Vibration Control
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作者 Tingrui Liu Qinghu Cui Dan Xu 《Fluid Dynamics & Materials Processing》 2025年第1期1-36,共36页
With the gradual increase in the size and flexibility of composite blades in large wind turbines,problems related toaeroelastic instability and blade vibration are becoming increasingly more important.Given their impa... With the gradual increase in the size and flexibility of composite blades in large wind turbines,problems related toaeroelastic instability and blade vibration are becoming increasingly more important.Given their impact on thelifespan of wind turbines,these subjects have become important topics in turbine blade design.In this article,firstaspects related to the aeroelastic(structural and aerodynamic)modeling of large wind turbine blades are summarized.Then,two main methods for blade vibration control are outlined(passive control and active control),including the case of composite blades.Some improvement schemes are proposed accordingly,with a specialfocus on the industry’s outstanding suppression scheme for stall-induced nonlinear flutter and a new high-frequencymicro-vibration control scheme.Finally,future research directions are indicated based on existingresearch. 展开更多
关键词 Aeroelastic instability vibration control composite blade stall-induced nonlinear flutter high-frequency microvibration
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Unveiling the prescription patterns and mechanisms of Chinese herbal compound patents in the management of acute appendicitis:A data mining investigation
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作者 Yuewen Li Qinsheng Zhang Suqin Hu 《Journal of Chinese Pharmaceutical Sciences》 2025年第6期566-580,共15页
In the present study,data mining and network pharmacology were utilized to explore the principles and mechanisms of traditional Chinese medicine(TCM)in treating acute appendicitis.The goal was to provide a scientific ... In the present study,data mining and network pharmacology were utilized to explore the principles and mechanisms of traditional Chinese medicine(TCM)in treating acute appendicitis.The goal was to provide a scientific basis for clinical treatment and further research on this disease.First,we searched the National Patent Database for Chinese herbal compound prescriptions used to treat acute appendicitis.We then applied frequency analysis,character and taste meridian analysis,association rule analysis,and hierarchical cluster analysis to identify the patterns of TCM treatment for acute appendicitis,selecting key combinations of Chinese medicines.Next,we screened the main active components of these key TCM based on quality markers.Using databases such as SwissTargetPrediction,SymMap,ETCM,and STRING,we analyzed the pharmacological mechanisms of these key TCM in treating acute appendicitis.Key active components and targets were further verified through molecular docking.We identified a total of 129 patents involving 316 Chinese medicines,with 24 being frequently used.The results indicated that most Chinese herbs used for acute appendicitis were heat-clearing drugs,blood-activating and stasis-removing drugs,and purging drugs.The primary active ingredients of the Rhubarb-cortex moutan-flos lonicerae combination for treating acute appendicitis included Emodin,Paeonol,Physcion,Chlorogenic acid,Chrysophanol,Rhein acid,and Aloe-emodin.These ingredients targeted key proteins such as ALB,TP53,BCL2,STAT3,IL-6,and TNF,and were involved in cellular responses to lipopolysaccharides,cell composition,and various cytokine-mediated biological processes.They also interacted with signaling pathways like AGE-RAGE,TNF,IL-17,and FoxO.Based on patent data,this study analyzed medication patterns in the treatment of acute appendicitis,discussed the possible mechanisms of key TCM combinations,and provided a scientific basis and new perspectives for the diagnosis and treatment of the disease. 展开更多
关键词 Acute appendicitis Data mining Rule of composition Hierarchical clustering Molecular docking
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Experimental study of postcritical deformation stage realization in layered composites during tension using digital image correlation and acoustic emission
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作者 Valeriy Wildemann Elena Strungar +2 位作者 Dmitrii Lobanov Artur Mugatarov Ekaterina Chebotareva 《Acta Mechanica Sinica》 2025年第2期163-175,共13页
Creating conditions to implement equilibrium processes of damage accumulation under a predictable scenario enables control over the failure of structural elements in critical states.It improves safety and reduces the ... Creating conditions to implement equilibrium processes of damage accumulation under a predictable scenario enables control over the failure of structural elements in critical states.It improves safety and reduces the probability of catastrophic behavior in case of accidents.Equilibrium damage accumulation in some cases leads to a falling part(called a postcritical stage)on the material’s stress-strain curve.It must be taken into account to assess the strength and deformation limits of composite structures.Digital image correlation method,acoustic emission(AE)signals recording,and optical microscopy were used in this paper to study the deformation and failure processes of an orthogonal-layup composite during tension in various directions to orthotropy axes.An elastic-plastic deformation model was proposed for the composite in a plane stress condition.The evolution of strain fields and neck formation were analyzed.The staging of the postcritical deformation process was described.AE signals obtained during tests were studied;characteristic damage types of a material were defined.The rationality and necessity of polymer composites’postcritical deformation stage taken into account in refined strength analysis of structures were concluded. 展开更多
关键词 Experimental mechanics Digital image correlation method Acoustic emission Postcritical deformation Polymer composite
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Compositional and functional succession of soil bacterial communities during long-term rice cultivation on saline-alkali soils:Insights derived from a new perspective on core bacterial taxa
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作者 Yu SUN Li JI +4 位作者 Jingjing CHANG Yingxin LI Hongbin WANG Deliang LU Chunjie TIAN 《Pedosphere》 2025年第4期641-654,共14页
The conversion of saline-alkali soils into paddy fields for long-term rice cultivation involves multiple disturbances,and as a result,soil microbial communities are altered to adapt to changing environmental condition... The conversion of saline-alkali soils into paddy fields for long-term rice cultivation involves multiple disturbances,and as a result,soil microbial communities are altered to adapt to changing environmental conditions.However,a comprehensive understanding of the succession of soil bacterial communities that occurs during this process is still lacking.In the present study,we utilized data obtained from paddy fields of different rice cultivation years(0-23 years)to investigate the compositional and functional succession of soil bacterial communities.We focused on core bacterial taxa that were specifically enriched at different successional stages.Generalized joint attribute modeling(GJAM)was used to identify core bacterial taxa.Results indicated that the bare saline-alkali soil(0 year,prior to any rice cultivation)shared few core amplicon sequence variants(ASVs)with paddy fields.In the bare saline-alkali soil,Longimicrobiaceae from the phylum Gemmatimonadetes was dominant,while the dominance was subsequently replaced by Burkholderiaceae and Pedosphaeraceae--phyla affiliated with Proteobacteria and Verrucomicrobia--after 5 and 23 years of rice cultivation,respectively.The relative abundances of nitrogen metabolism functions in the core bacterial communities of the bare saline-alkali soil were higher than those at other successional stages,while sulfur metabolism functions exhibited the opposite trend.These indicated that the role of the core bacterial taxa in mediating nutrient cycling also evolved and adapted to changing soil conditions as rice cultivation was established.Redundancy analysis(RDA)indicated that the composition of the core bacterial community in paddy fields with rice cultivation for 0,2 and 4,6,8,10,and 12,and 20 and 23 years were driven by soil nitrate nitrogen content,pH,available phosphorus content,and the ratio of total carbon to total nitrogen,respectively.In summary,the present study provides insights into the succession of soil bacterial communities and core bacterial taxa that occurs during long-term rice cultivation. 展开更多
关键词 bacterial compositional analysis ecosystem functions generalized joint attribute modeling paddy field soil bacterial succession
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Efficient breeding of high oleic rice cultivar by editing OsFAD2-1 via CRISPR/Cas9
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作者 Yingying Wu Zhihui Chen +5 位作者 Chan Wang Yang Xu Xia Li Jianping Zhu Xiaoli Tan Jie Yang 《Journal of Integrative Agriculture》 2025年第12期4810-4814,共5页
Rice(Oryza sativa L.)is a globally important food crop.Its bran oil has high nutritional value,but with a low content of oleic acid and a high content of linoleic acid,which affects the stability and shelf life of the... Rice(Oryza sativa L.)is a globally important food crop.Its bran oil has high nutritional value,but with a low content of oleic acid and a high content of linoleic acid,which affects the stability and shelf life of the oil(Warner et al.2008;Liang et al.2017;Doureradjou and Koner 2020;Ghasemzadeh et al.2020).The fatty acid composition of rice bran oil is one of the healthiest edible oils due to its balanced source of saturated,monounsaturated,and polyunsaturated fatty acids with a ratio of 0.6:1.1:1(Liang et al.2017;Awad et al.2022). 展开更多
关键词 edible oils osfad bran oil fatty acids criSPR Cas fatty acid composition high oleic rice oleic acid
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A Self-Sacrifice Template Method to Produce FeS Encapsulated into N,S Co-Doped Carbon for Improved Lithium Storage Performance
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作者 Xu Liu Lan-Yun Yang +7 位作者 Li-Ting Zeng Yun Peng Chen-Xi Xu Lei Li Jia-Le Sun Yang-Yang Chen Liang Chen Zhao-Hui Hou 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1637-1644,共8页
The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile ... The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems. 展开更多
关键词 Lithium-ion batteries Lithium storage performance Self-sacrifice template method Melamine-cyanuric acid(MCA)supermolecule FeS encapsulated into N S co-doped carbon(FeS/NSC)composite
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基于AHP-CRITIC复合加权法正交优选重楼酒制工艺 被引量:1
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作者 蔡吹 余红娅 +4 位作者 谢准 李世昌 刘光华 单叶婷 徐福荣 《时珍国医国药》 北大核心 2025年第8期1474-1481,共8页
目的 优选重楼酒制的最佳炮制工艺参数,为酒重楼饮片的开发利用提供参考依据。方法 采用HPLC法分析酒重楼中重楼皂苷Ⅰ、重楼皂苷Ⅱ和重楼皂苷Ⅶ的含量;热浸法测定水溶性浸出物的含量。以重楼皂苷Ⅰ、Ⅱ、Ⅶ的含量及水溶性浸出物含量为... 目的 优选重楼酒制的最佳炮制工艺参数,为酒重楼饮片的开发利用提供参考依据。方法 采用HPLC法分析酒重楼中重楼皂苷Ⅰ、重楼皂苷Ⅱ和重楼皂苷Ⅶ的含量;热浸法测定水溶性浸出物的含量。以重楼皂苷Ⅰ、Ⅱ、Ⅶ的含量及水溶性浸出物含量为评价指标,通过AHP-CRITIC复合加权法确定各指标的权重系数并计算综合评分。在单因素实验的基础上,以黄酒用量、炒制温度、炒制时间、闷润时间为主要因素建立正交实验,确定最佳炮制工艺参数,比较炮制前后含量差异。结果 各因素对重楼炮制工艺质量影响的大小顺序为黄酒用量>炒制温度>炒制时间>闷润时间,最佳工艺参数为每100 g重楼,加黄酒25 g,炒制温度120℃,炒制时间20 min,闷润时间5 h。重楼经酒制后皂苷Ⅰ、Ⅱ、Ⅶ的含量均显著升高,浸出物含量减少。结论 实验优化所得的重楼酒制工艺稳定可行,可为重楼生产加工及质量标准的建立提供参考。 展开更多
关键词 重楼 正交试验 AHP-criTIC复合加权法 酒制 工艺优选
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性腺发育不同时期雌性红九棘鲈肌肉营养成分的分析与评价
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作者 李雪 陈张帆 +3 位作者 卢昇 王崇伟 李超伟 陈松林 《渔业科学进展》 北大核心 2026年第1期70-80,共11页
为探究雌性红九棘鲈(Cephalopholis sonnerati)不同生长阶段肌肉的营养价值和肌肉营养组成变化规律,本研究对红九棘鲈性腺发育不同时期(Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ期)肌肉的营养成分进行了分析,并通过计算氨基酸评分(AAS)、化学评分(CS)和必需... 为探究雌性红九棘鲈(Cephalopholis sonnerati)不同生长阶段肌肉的营养价值和肌肉营养组成变化规律,本研究对红九棘鲈性腺发育不同时期(Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ期)肌肉的营养成分进行了分析,并通过计算氨基酸评分(AAS)、化学评分(CS)和必需氨基酸指数(EAAI)等指标评价了其肌肉品质。结果显示,在雌性红九棘鲈性腺Ⅰ~Ⅴ期发育过程中,水分和蛋白含量呈持续上升趋势,脂肪含量Ⅳ期达到最高,随后在Ⅴ期下降。红九棘鲈肌肉中检测出的16种氨基酸总量为(18.20±0.26)%~(19.63±0.06)%,在卵巢发育Ⅰ~Ⅴ期过程中呈上升趋势,其中,包含人体所需的7种必需氨基酸,4种主要呈味氨基酸总量为(7.00±0.04)%~(7.55±0.07)%。此外,在肌肉中共检测出25种脂肪酸,含量最高的C16:0和C18:1随红九棘鲈性腺发育呈下降的趋势;而DHA+EPA含量呈先下降后上升的趋势。另外,红九棘鲈肌肉中矿物质含量分析结果显示,红九棘鲈肌肉具有丰富的矿物质,检测到5种常量元素及3种微量元素,且Ⅴ期亲鱼的含硒量高于其他石斑鱼类。本研究揭示了红九棘鲈不同生长阶段肌肉的营养价值和肌肉营养组成变化规律,为红九棘鲈不同发育时期配合饲料的研制和营养价值评价提供了科学依据,并为进一步开展红九棘鲈人工规模化养殖实践奠定了理论基础。 展开更多
关键词 红九棘鲈 肌肉 营养成分 性腺发育
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温度对CrIS热红外卫星资料反演臭氧廓线的影响分析 被引量:3
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作者 马鹏飞 陈良富 +4 位作者 邹铭敏 张莹 陶明辉 王子峰 苏林 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2015年第12期3344-3349,共6页
臭氧是地球大气中一种重要的痕量气体,在光化学反应和气候变化中都扮演着非常重要的角色。高光谱红外卫星可以观测到较高垂直分辨率的大气臭氧信息,但是由于热红外受大气温度影响较大,臭氧反演精度会有所下降。为此详细讨论和分析了温... 臭氧是地球大气中一种重要的痕量气体,在光化学反应和气候变化中都扮演着非常重要的角色。高光谱红外卫星可以观测到较高垂直分辨率的大气臭氧信息,但是由于热红外受大气温度影响较大,臭氧反演精度会有所下降。为此详细讨论和分析了温度对臭氧吸收光谱和权重函数的敏感性,以及对臭氧反演精度的影响。首先利用逐线积分辐射传输模型LBLRTM,分别模拟计算了六种不同标准大气模式下,1K的随机温度误差对大气透过率和辐射值的影响,发现1K温度随机误差和臭氧浓度5%-6%的变化引起的辐射值变化量一致。接着利用CRTM辐射传输模型,针对搭载于美国对地观测卫星Suomi NPP(National Polar-orbiting Partnership)平台上的CrIS(Cross-track Infrared Sounder)红外高光谱观测数据,计算了1K的随机温度误差对大气臭氧权重函数的影响,并计算了由1K温度误差所导致的热红外高光谱资料大气臭氧廓线反演误差,结果显示CrIS对于臭氧的敏感区位于10-100hPa之间,且1K的温度误差和6%的臭氧浓度变化引起的权重函数变化量相当。最后以CrIS作为实验数据,在最优估计法框架下,通过特征向量统计法获取臭氧廓线的先验知识,并将大气温度廓线和大气臭氧廓线都作为未知量,进行同步迭代反演。将反演结果和配对的世界臭氧紫外数据中心WOUDC的站点数据进行比较,发现在反演中加入大气温度廓线进行同步迭代后,反演结果有显著提高,尤其在平流层与真值几乎一致,最大相对误差不超过20%,在对流层反演结果相对较差,最大相对误差不超过50%,优于欧洲中期天气预报中心ECMWF(European Center for Medium-range Weather Forecasting)臭氧模式数据集ERA-Interim。 展开更多
关键词 criS 温度廓线 臭氧廓线
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混合流体岩石介电常数的CRI模型与Maxwell-Garnett模型研究 被引量:6
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作者 潘保芝 栗猛 张瑞 《测井技术》 CAS CSCD 2016年第3期257-261,共5页
计算了混合流体岩石介电特性的CRI模型和Maxwell-Garnett模型,研究岩石介电常数与矿化度、饱和度、频率、比表面的关系。水的介电常数计算模型采用了矿化度适用范围较大的Stogryn模型;对椭球颗粒岩石骨架计算了比表面,分析了比表面与介... 计算了混合流体岩石介电特性的CRI模型和Maxwell-Garnett模型,研究岩石介电常数与矿化度、饱和度、频率、比表面的关系。水的介电常数计算模型采用了矿化度适用范围较大的Stogryn模型;对椭球颗粒岩石骨架计算了比表面,分析了比表面与介电常数的关系,通过计算发现矿化度、饱和度、比表面、孔隙度都会影响岩石介电常数,而且影响程度与频率有关。岩石介电常数随含水饱和度增大的变化速率先快后慢是骨架颗粒和水之间的界面极化导致的。将前人的实验数据与研究实验模型计算比较,验证了2种模型的合理性。 展开更多
关键词 岩电实验 介电常数 模型 cri Maxwell-Garnett
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仿木年轮结构Si_(3)N_(4)/Ni和316配副在海洋环境中的摩擦磨损性能研究
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作者 陈威 王朝 +4 位作者 周奥 李耶童 赵文卓 张建军 杨勇强 《陕西科技大学学报》 北大核心 2026年第1期152-160,共9页
本论文系统研究了仿木年轮Si_(3)N_(4)/Ni复合材料在海水中的摩擦磨损性能.在本研究中,利用热压烧结工艺制备仿木年轮的Si_(3)N_(4)/Ni复合材料,采用端面磨损试验机研究Si_(3)N_(4)/Ni复合材料与316不锈钢配副在人工海水环境中的摩擦磨... 本论文系统研究了仿木年轮Si_(3)N_(4)/Ni复合材料在海水中的摩擦磨损性能.在本研究中,利用热压烧结工艺制备仿木年轮的Si_(3)N_(4)/Ni复合材料,采用端面磨损试验机研究Si_(3)N_(4)/Ni复合材料与316不锈钢配副在人工海水环境中的摩擦磨损性能,利用扫描电子显微镜(SEM)观察与分析摩擦副表面的磨损形貌,采用EDS能谱仪和拉曼光谱来定性分析磨损面的表面元素与物质分布.结果表明,随着滑动速度增大,纯氮化硅和Si_(3)N_(4)/Ni复合材料与316不锈钢配副的摩擦系数均有所增大,在相同速度下,Si_(3)N_(4)/Ni复合材料与316配副表现出较好的摩擦磨损性能.当滑动速度为100 r/min时,Si_(3)N_(4)/Ni-316摩擦副表现出最优的摩擦学性能,摩擦系数为0.45,复合材料销磨损率为1.503×10^(-6)mm^(3)/Nm,金属盘磨损率为1.03×10^(-4)mm^(3)/Nm.Si_(3)N_(4)/Ni复合材料表现出相对较好的摩擦学性能,这主要归因于在复合材料摩擦表面发生了摩擦化学反应,生成硅胶(SiO_(2))和Ni_(2)SiO_(4)等物质,起到了减摩与润滑作用. 展开更多
关键词 Si_(3)N_(4)复合陶瓷 海水环境 摩擦磨损
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