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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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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:5
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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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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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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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基于AHP-CRITIC复合加权法正交优选重楼酒制工艺 被引量:2
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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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柴胡化学成分、药理、炮制研究进展 被引量:1
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作者 胡振宇 陈春羽 +3 位作者 施林峰 卜俊文 钟凌云 叶喜德 《中华中医药学刊》 北大核心 2026年第1期187-194,I0028-I0030,共11页
柴胡是我国常用中药材,具有疏散退热、疏肝解郁、升举阳气、清胆截疟等功效,主含皂苷类、黄酮类、多糖和香豆素类等多种成分,具有抗炎镇痛、抗抑郁、抗肿瘤、抗纤维化和降血脂等作用。对柴胡研究进行了文献梳理,在整理有关的本草古籍和... 柴胡是我国常用中药材,具有疏散退热、疏肝解郁、升举阳气、清胆截疟等功效,主含皂苷类、黄酮类、多糖和香豆素类等多种成分,具有抗炎镇痛、抗抑郁、抗肿瘤、抗纤维化和降血脂等作用。对柴胡研究进行了文献梳理,在整理有关的本草古籍和炮制规范的过程中发现,柴胡在悠久的药用历史中形成了众多炮制品种,但现代研究多集中于柴胡生品以及醋制品种上,且近年来的研究重点也多以基因表达和柴胡方剂为主。通过对近年来开展的文献研究进行分析,从化学成分、药理作用和炮制历史沿革等方面进行了归纳总结,为深入探究柴胡生品及其炮制品的药理作用及机制提供参考。 展开更多
关键词 柴胡 炮制 历史沿革 药理作用 化学成分
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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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水泥基植物纤维预制装配式叠合板受弯性能研究
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作者 张望喜 张晨 +3 位作者 谢向荣 袁超 周益渤 易伟建 《湖南大学学报(自然科学版)》 北大核心 2026年第3期44-54,共11页
为研究水泥基植物纤维叠合板的受弯性能,对10块足尺叠合板进行四点受弯试验,测得相应的荷载-挠度曲线、荷载-应变曲线、破坏形式及相应的破坏荷载等,分析混凝土叠合层厚度、保护层厚度对叠合板力学性能的影响,包括预制底板对叠合板的抗... 为研究水泥基植物纤维叠合板的受弯性能,对10块足尺叠合板进行四点受弯试验,测得相应的荷载-挠度曲线、荷载-应变曲线、破坏形式及相应的破坏荷载等,分析混凝土叠合层厚度、保护层厚度对叠合板力学性能的影响,包括预制底板对叠合板的抗裂性能和破坏模式的影响以及承载过程中截面的受力情况.结果表明:由于水泥基植物纤维底板的材料特性,承受正弯矩的叠合板的破坏模式与现浇混凝土板存在差异,水泥基纤维叠合板在开裂前无明显前兆,开裂较为突然,表现为预制底板中的玻璃纤维网整体性拉断,玻璃纤维增强塑料(glass fiber reinforced plastics,GFRP)网格拉断后,叠合板的承载力会有小幅度下降;在受拉侧设置水泥基纤维板,可提高叠合板的极限承载力与延性;预制底板与后浇混凝土的协同受力性能良好,叠合面未出现滑移现象.承受负弯矩的叠合板在达到极限承载力时,上层钢筋和底层钢筋均处于受拉屈服状态,其极限承载力较现浇混凝土板有所降低,破坏模式与适筋板破坏相似.此外,将受拉区水泥基植物纤维预制板的应力等效为拉力F_(g),受压区水泥基植物纤维预制板等效为厚度为d的混凝土层,根据试验数据算得F_(g)和d的值,并对规范公式进行修正. 展开更多
关键词 预制装配式叠合板 植物纤维水泥基材料 GFRP网格加固 受弯性能
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考虑围压变化的灰土桩复合地基沉降计算方法 被引量:1
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作者 李哲 马季 +1 位作者 刘路路 夏树峥 《西安建筑科技大学学报(自然科学版)》 北大核心 2026年第1期15-25,共11页
近年来,各种建筑物在填方工程中应用灰土桩复合地基的模式逐渐增多,在使用这些建筑时,由于填方复合地基倾斜沉降,致使建筑物倾斜,阻碍建筑物的正常运行,因此需要对填方灰土桩复合地基沉降计算问题进行深入研究,这对建筑物的正常运行具... 近年来,各种建筑物在填方工程中应用灰土桩复合地基的模式逐渐增多,在使用这些建筑时,由于填方复合地基倾斜沉降,致使建筑物倾斜,阻碍建筑物的正常运行,因此需要对填方灰土桩复合地基沉降计算问题进行深入研究,这对建筑物的正常运行具有重大意义.本文应用室内自研三向加载设备进行静止土压力试验和三向压缩试验,阐述了填土及灰土的沉降变形特征,修正了复合模量法中计算复合模量的公式,提出了填方灰土桩复合地基的沉降计算公式,并对其进行了验证.主要研究工作及成果如下:填土及灰土的静止土压力系数分别为0.312和0.217;填土在不同围压下,竖向应变与侧向应变随竖向荷载增大而增大,随围压增大而减小,竖向应变增长速率越来越小,侧向应变增长速率越来越大;灰土也有同样上述规律,但随着龄期的增大,竖向及侧向应变逐渐减小;提出了考虑不同地基深度下的复合模量计算公式,推导出填方灰土桩复合地基沉降计算公式,通过工程实例计算,证明此公式可以提高计算精度. 展开更多
关键词 复合地基 沉降计算 公式修正 填方路基
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轻钢轻混凝土组合墙板平面外受力性能试验研究
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作者 董宏英 王瑞 +2 位作者 曹万林 杨兆源 刘思源 《建筑结构》 北大核心 2026年第5期51-58,共8页
为适应装配式建筑的发展,提出了一种轻钢轻混凝土组合墙板,由轻钢龙骨与轻质泡沫颗粒混凝土组合而成。为研究风荷载作用下轻钢轻混凝土组合墙板的受弯性能,对3个足尺轻钢轻混凝土组合墙板进行了平面外加载试验。组合墙板通过自攻钉与轻... 为适应装配式建筑的发展,提出了一种轻钢轻混凝土组合墙板,由轻钢龙骨与轻质泡沫颗粒混凝土组合而成。为研究风荷载作用下轻钢轻混凝土组合墙板的受弯性能,对3个足尺轻钢轻混凝土组合墙板进行了平面外加载试验。组合墙板通过自攻钉与轻钢框架上的角钢件连接。集中力通过简支分配梁形成四点加载模式以模拟均布荷载,加载点设置球铰支座。分析了墙板内部轻钢龙骨壁厚、墙板两侧是否复合轻质泡沫颗粒混凝土钢丝网层及高性能抗裂砂浆层等因素对组合墙板的荷载-挠度曲线和破坏模式的影响。基于试验结果,结合静力平衡条件和虚功原理,推导出组合墙板平面外极限抗弯承载力计算公式,计算结果与试验符合较好。研究表明:该墙板具有良好的抗弯刚度和弹塑性变形能力;减小内部轻钢龙骨厚度对墙板平面外极限承载力和刚度有一定削弱;墙体内外叶砂浆面层构造对组合墙板承载力有显著增强作用。 展开更多
关键词 装配式建筑 轻钢组合结构 轻钢轻混凝土组合墙板 受力性能 试验研究
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