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Two simple memristive maps with adaptive energy regulation and digital signal process verification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 382-394页

作者： feifei yang Lujie REN Jun MA Zhigang ZHU College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China School of Information Science and Engineering Dalian Polytechnic UniversityDalian 116034China

Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy *** involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive *** this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural *** corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear *** Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive *** Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and *** two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these *** scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.

关键词： Hamilton energy Discrete memristor Self-adaptive regulation Digital signal process(DSP)implementation

Effect of reduction pretreatment on the structure and catalytic performance of Ir-In_(2)O_(3)catalysts for CO_(2) hydrogenation to methanol

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Journal of Environmental Sciences 2024年第6期140卷 2-11页

作者： Changyu Ding feifei yang Xue Ye Chongya yang Xiaoyan Liu Yuanlong Tan Zheng Shen Hongmin Duan Xiong Su Yanqiang Huang CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this ***,there remains a great challenge to understand the relations between the state of oxygen species in In_(2)O_(3)and the catalytic performance for CO_(2)hydrogenation to *** the present work,we compare the properties of multiple In_(2)O_(3)and Ir-promoted In_(2)O_(3)(Ir-In_(2)O_(3))catalysts with different Ir loadings and after being pretreated under different reduction *** CO_(2)conversion rate of Ir-In_(2)O_(3)is more promoted than that of pure In_(2)O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2)O_(3)increase the concentration of O_(v)sites and enhance the *** finely tuning the catalyst structure,Ir-In_(2)O_(3)with an Ir loading of 0.16 wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 146 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2)-temperature programmed desorption and CO_(2)-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2)adsorption and desorption *** performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.

关键词： Carbon dioxide Hydrogenation Methanol In_(2)O_(3) Fixed-bed Reduction temperature

Crop pest image recognition based on the improved ViT method Author links open overlay panel

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Information Processing in Agriculture 2024年第2期11卷 249-259页

作者： Xueqian Fu Qiaoyu Ma feifei yang Chunyu Zhang Xiaolong Zhao Fuhao Chang Lingling Han College of Information and Electrical Engineering China Agricultural UniversityBeijingChina National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina

The crop pests and diseases in agriculture is one of the most important reason for the reduction of bulk grain and oil crops and the decline of fruit and vegetable crop quality,which threaten macroeconomic stability and sustainable ***,the recognition method based on manual and instruments has been unable to meet the needs of scientific research and production due to its strong subjectivity and low *** recognition method based on pattern recognition and deep learning can automatically fit image features,and use features to classify and predict *** study introduced the improved Vision Transformer(ViT)method for crop pest image *** them,the region with the most obvious features can be effectively selected by block *** self-attention mechanism of the transformer can better excavate the special solution that is not an obvious lesion *** the experiment,data with 7 classes of examples are used for *** can be illustrated from results that this method has high accuracy and can give full play to the advantages of image processing and recognition technology,accurately judge the crop diseases and pests category,provide method reference for agricultural diseases and pests identification research,and further optimize the crop diseases and pests control work for agricultural workers in need.

关键词： Crop diseases recognition Fruit tree leaf disease Vision Transformer Deep learning Computer Vision

First total synthesis,antitumor evaluation and target identification of mornaphthoate E:A new tubulin inhibitor template acting on PI3K/Akt signaling pathway

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2177-2193页

作者： Peipei Shan Tao Ye Ying-De Tang Hui Song Chao Wang Kongkai Zhu feifei yang Shi-Lei Zhang Pei-Wen Su Shuanhu Gao Hua Zhang Institute of Translational Medicine the Affiliated Hospital of Qingdao UniversityCollege of MedicineQingdao UniversityQingdao 266021China School of Biological Science and Technology University of JinanJinan 250022China Advanced Medical Research Institute Cheeloo College of MedicineShandong UniversityJinan 250012China College of Pharmaceutical Sciences Soochow UniversitySuzhou 215127China School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China

Mornaphthoate E(MPE)is a prenylated naphthoic acid methyl ester isolated from the roots of a famous Chinese medicinal plant Morinda officinalis and shows remarkable cytotoxicity against several human tumor cell *** the current project,the first total synthesis of(±)-MPE was achieved in seven steps and 5.6%overall *** the in vitro anti-tumor activity of MPE was first assessed for both enantiomers in two breast cancer cells,with the levoisomer exerting slightly better *** in vivo anti-tumor effect was further verified by applying the racemate in an orthotopic autograft mouse ***,MPE exerted promising anti-metastasis activity both in vitro and in vivo and showed no obvious toxicity on mice at the therapeutic *** investigations demonstrated that MPE acted as a tubulin polymerization stabilizer and disturbed the dynamic equilibrium of microtubules via regulating PI3K/Akt *** conclusion,our work has provided a new chemical template for the future design and development of next-generation tubulin-targeting chemotherapies.

关键词： Mornaphthoate E Tubulin inhibitor Antitumor Anti-metastasis Breast cancer PI3K/Akt

考虑频率二次跌落和转速恢复的风电机组柔性频率响应策略

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电力系统自动化 2024年第13期48卷 60-68页

作者：陶玉昆杨飞飞和萍李从善季玉琦郑州轻工业大学电气信息工程学院河南省郑州市450002

风电机组具备主动频率响应能力成为未来风电并网的前提条件,但频率支撑阶段与转速恢复阶段间控制策略切换不当可能引起系统频率二次跌落。针对这一问题,文中提出一种风电机组柔性频率响应策略。首先,在初始运行点将风电机组非线性模型... 详细信息

风电机组具备主动频率响应能力成为未来风电并网的前提条件,但频率支撑阶段与转速恢复阶段间控制策略切换不当可能引起系统频率二次跌落。针对这一问题,文中提出一种风电机组柔性频率响应策略。首先,在初始运行点将风电机组非线性模型线性化,分析初始运行点对风电机组出力特性的影响;其次,基于风电机组线性化模型推导包含风电和火电的电力系统频率响应传递函数,分析系统参数对频率响应动态特性的影响;然后,研究频率二次跌落和转速恢复间的矛盾,利用分段函数和Logistic函数构造附加功率参与因子,通过形状系数调节风电机组输出电磁功率;最后,基于MATLAB/Simulink平台进行对比仿真研究。仿真结果表明,所提出的策略在消除频率二次跌落的同时,具有良好的转速恢复过程。

关键词：风电机组主动频率响应频率二次跌落转速恢复频率响应模型

LncRNA GABPB1-AS1调控急性髓系白血病细胞增殖侵袭迁移及凋亡的作用和机制

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中国肿瘤临床 2024年第8期51卷 392-400页

作者：杨菲菲唐浩孙慧孙寅滕州市中心人民医院儿科山东省滕州市277500

目的:探究长非编码RNA(long non-coding RNA,LncRNA)GA结合蛋白转录因子β亚基1的反义RNA(antisense RNA of GA binding protein transcription factorβsubunit 1,GABPB1-AS1)靶向微小RNA-497-5p/热休克蛋白8(microRNA-497-5p/heat shock protein 8,miR-497-5p/HSPA8)轴调控急性髓系白血病(acute myeloid leukemia,AML)细胞增殖、侵袭迁移及凋亡的作用和机制。方法:HL-60细胞分为正常对照组、si-NC组、si-GABPB1-AS1组、si-GABPB1-AS1+NC inhibitor组、si-GABPB1-AS1+miR-497-5p inhibitor组。qRT-PCR检测LncRNA GABPB1-AS1、miR-497-5p和HSPA8表达;双荧光素酶报告基因实验验证LncRNA GABPB1-AS1、miR-497-5p和HSPA8的靶向关系;MTT检测细胞活力;Edu检测细胞增殖;Transwell小室实验检测侵袭和迁移;流式细胞仪检测细胞凋亡;Western blot检测增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)、HSPA8、肿瘤转移相关蛋白2(metastasis-associated proteins,MTA2)、酵母Atg6同系物(homolog of yeast Atg6,Beclin-1)和Caspase-3蛋白水平;建立小鼠移植瘤模型验证LncRNA GABPB1-AS1对AML移植瘤生长的影响。结果:与人骨髓单核细胞相比,不同AML细胞系THP-1、NB4、U-937、HL-60中LncRNA GABPB1-AS1高表达[(1.29±0.10)、(1.58±0.12)、(2.02±0.17)、(3.17±0.24)vs.(1.02±0.07)]、miR-497-5p低表达[(0.94±0.07)、(0.75±0.03)、(0.57±0.03)、(0.25±0.01)vs.(1.05±0.09)]。由于HL-60细胞中LncRNA GABPB1-AS1表达最高,故选择该细胞系进行功能验证实验。敲低LncRNA GABPB1-AS1能降低HL-60细胞活力、Edu阳性率、细胞侵袭数、迁移数、HSPA8 mRNA及HSPA8、PCNA和MTA2蛋白表达,增加凋亡率、miR-497-5p及Caspase-3和Beclin-1蛋白表达(P<0.05)。miR-497-5p与LncRNA GABPB1-AS1、HSPA8之间分别存在靶向关系;抑制miR-497-5p表达能逆转LncRNA GABPB1-AS1敲低对HL-60细胞恶性生物学行为的抑制作用;抑制LncRNA GABPB1-AS1表达可抑制移植瘤生长。结论:LncRNA GABPB1-AS1敲低对AML细胞进展抑制作用,可能与上调miR-497-5p表达,下调HSPA8表达有关。

关键词：急性髓系白血病 GABPB1-AS1 增殖侵袭凋亡

K修饰MoS_(2)催化剂用于CO_(2)高选择性加氢制甲醇

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物理化学学报 2024年第7期40卷 58-60页

作者：杨菲菲周维杨超然张天雨黄延强中国矿业大学化工学院江苏徐州221116 北京林业大学环境科学与工程学院水体污染源控制技术北京市重点实验室北京100083 北京林业大学环境科学与工程学院污染水体源控和生态修复工程研究中心北京100083 中国科学院大连化学物理研究所应用催化重点实验室辽宁大连116023

在CO_(2)加氢领域,MoS_(2)催化剂表现出独特的潜力。然而MoS_(2)的边缘S空位对CH_(4)的生成更有利,这限制了目标产物甲醇的选择性。本工作中,我们发现,通过掺杂K助剂可以显著提高MoS_(2)催化CO_(2)选择性加氢制甲醇的性能,而未修饰的MoS... 详细信息

在CO_(2)加氢领域,MoS_(2)催化剂表现出独特的潜力。然而MoS_(2)的边缘S空位对CH_(4)的生成更有利,这限制了目标产物甲醇的选择性。本工作中,我们发现,通过掺杂K助剂可以显著提高MoS_(2)催化CO_(2)选择性加氢制甲醇的性能,而未修饰的MoS_(2)主要产生CH_(4)。通过一系列的表征研究,我们发现,K原子更倾向于稳定在MoS_(2)的边缘位点上,并向MoS_(2)转移电子,从而增强了MoS_(2)边缘位点的碱性。这有助于CO_(2)的吸附活化,并以较低的能垒解离为CO。此外,K助剂还有助于调控CO中间体定向转化为甲醇而非CH_(4)。这一发现拓展了MoS_(2)材料在CO_(2)合成甲醇中的应用。通过掺杂K助剂,我们能够更高效地利用MoS_(2)催化CO_(2)转化为甲醇,对于减缓气候变化和开发清洁能源具有重要意义。

关键词： CO_(2)加氢甲醇甲烷选择性调控 K-MoS_(2)

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流域水污染事件环境应急防控与处置研究

皮革制作与环保科技 2024年第10期5卷 145-147页

作者：阳菲菲贵州楚天环境检测有限公司贵州贵阳550014

突发水污染事件是由于环境污染而造成的突发性水污染事故,常常会造成跨界污染,主要是因为进入水体中的污染物迁移扩散速度快、围堵拦截难。贵州地处云贵高原,喀斯特岩溶地貌发育典型,河流的山区性特征明显,多数河流上游河谷开阔,水流平... 详细信息

突发水污染事件是由于环境污染而造成的突发性水污染事故,常常会造成跨界污染,主要是因为进入水体中的污染物迁移扩散速度快、围堵拦截难。贵州地处云贵高原,喀斯特岩溶地貌发育典型,河流的山区性特征明显,多数河流上游河谷开阔,水流平缓;中游河谷束放相间,水流湍急;下游河谷深切狭窄,水量大,河流平面形态以限制性顺直或弯曲河流为主。本文结合工作实践,以环境应急空间与设施操作使用说明为导向,为贵州省流域突发水污染事件的应急处置和应急事后管理提出对策和建议,以期为相关部门提供参考与借鉴。

关键词：突发水污染事件环境应急空间与设施应急处置应急风险防控体系

早期集束化护理结合饲管定位经鼻空肠营养干预ICU重症患者的效果分析

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蛇志 2024年第1期36卷 72-75页

作者：杨菲菲广西医科大学附属肿瘤医院重症医学科广西南宁530000

目的探讨早期集束化护理结合饲管定位经鼻空肠营养干预ICU重症患者的效果。方法选取2022年6月至2023年6月在我院ICU重症病房收治的120例患者作为研究对象,按照随机数字表法分为观察组和对照组,每组60例。对照组采取ICU重症病房标准护理... 详细信息

目的探讨早期集束化护理结合饲管定位经鼻空肠营养干预ICU重症患者的效果。方法选取2022年6月至2023年6月在我院ICU重症病房收治的120例患者作为研究对象,按照随机数字表法分为观察组和对照组,每组60例。对照组采取ICU重症病房标准护理方案并给予常规肠内营养干预,观察组采取早期集束化护理和饲管定位经鼻空肠营养干预,观察比较两组患者的干预效果。结果护理后,两组患者的血清白蛋白(ALB)、前白蛋白(PA)和血红蛋白(Hb)水平均有所上升,且观察组患者的ALB、PA和Hb水平均高于对照组,差异均有统计学意义(均P0.05);观察组患者的7 d热卡达标率明显高于对照组,差异有统计学意义(P<0.05)。结论在ICU重症患者的营养干预中,采取早期集束化护理结合饲管定位经鼻空肠营养干预可保证患者热能和营养摄入,有效改善患者的营养状态,降低不良反应发生率,对促进患者康复具有重要意义,值得临床应用和推广。

关键词：集束化护理饲管定位经鼻空肠营养