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氨基改性埃洛石对Cu(II)和Cd(II)的吸附研究
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作者 肖雪 于文彬 +3 位作者 谭道永 吴兴福 覃宗华 万泉 《矿物学报》 北大核心 2025年第1期169-180,共12页
本研究采用3-氨丙基三乙氧基硅烷对管状埃洛石(Hal)进行共价接枝制备了氨基改性埃洛石(Hal-NH_(2)),通过XRD、TEM、SEM、氮气吸脱附等手段表征了Hal-NH_(2)的结构特征,并通过批次吸附实验、谱学技术研究了Hal-NH_(2)对Cu(II)和Cd(II)的... 本研究采用3-氨丙基三乙氧基硅烷对管状埃洛石(Hal)进行共价接枝制备了氨基改性埃洛石(Hal-NH_(2)),通过XRD、TEM、SEM、氮气吸脱附等手段表征了Hal-NH_(2)的结构特征,并通过批次吸附实验、谱学技术研究了Hal-NH_(2)对Cu(II)和Cd(II)的吸附性能及机理。Hal-NH_(2)中氨基主要存在于Hal的内腔,其氨基嫁接量为0.83 mmol/L,由于硅烷嫁接占据了部分内腔孔道,Hal-NH_(2)的比表面积和总孔体积较Hal明显降低。Hal-NH_(2)对Cu^(2+)和Cd^(2+)的吸附随溶液初始p H值的增大而增加,吸附时间为2160 min时达到吸附平衡,298 K时,Hal-NH_(2)对Cu^(2+)和Cd^(2+)的Langmuir吸附量分别为50.29和68.70 mg/g,是Hal的3.11和1.97倍。Hal-NH_(2)吸附Cu^(2+)和Cd^(2+)为自发的吸热反应,吸附后体系的混乱度增大,其吸附机制主要是氨基与重金属离子之间发生配位反应,且Hal-NH_(2)对Cu^(2+)的作用力强于Cd^(2+);Cu^(2+)和Cd^(2+)共存时,Hal-NH_(2)对Cu^(2+)的吸附基本不受影响,其对Cd^(2+)的吸附显著降低。由于其较高的吸附能力,Hal-NH_(2)可作为Cu(II)和Cd(II)吸附材料用于水体中重金属离子的去除,本研究为Hal在重金属污染治理领域的应用提供了实验和理论依据。 展开更多
关键词 埃洛石 氨基改性 吸附 重金属 CU(ii) CD(ii)
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Preliminary Investigation of Copper(II) Ion Binding or Complex Coordination in Lysozeme Molecules
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作者 Kou Takahashi Ryotaro Miyazaki +2 位作者 Daisuke Nakane Temitayo O. Aiyelabola Takashiro Akitsu 《Journal of Materials Science and Chemical Engineering》 2024年第4期98-103,共6页
Hydrophobic Val derivative Schiff base copper(II) complexes and dipeptide (AlaAla, GlyGly) derivative Schiff base copper(II) complexes were introduced into egg white lysozyme. X-ray crystal structure analysis revealed... Hydrophobic Val derivative Schiff base copper(II) complexes and dipeptide (AlaAla, GlyGly) derivative Schiff base copper(II) complexes were introduced into egg white lysozyme. X-ray crystal structure analysis revealed amino acid derivative Schiff base copper(II) complexes were obtained. Herein we discuss primarily on the binding mode of copper(II) of the complexes obtained with egg white lysozyme. The electron density of copper(II) ions was confirmed by X-ray crystal structure analysis. The Val derivative Schiff base copper(II) complex was weakly bound at Arg114 of egg white lysozyme. In other copper(II) complexes, binding of copper(II) ions with dissociated ligands to various residues was observed. The binding sites of copper(II) ions were compared with computational scientific predictions. 展开更多
关键词 copper Schiff Base LYSOZYME Metal-Protein Binding Computational Methods
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Stoichiometry and Stability Constant Values for Copper (II) Chelates with Ethylene Diamine in Deep Eutectic Solvents (DES) (Ethaline) Solutions
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作者 Khalid El Ttaib Abdolhadi Benhmid Rifat Hasan Omar 《Open Journal of Applied Sciences》 2024年第9期2592-2609,共18页
In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha... In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values. 展开更多
关键词 CU(ii) Ethylene Diamine (en) Deep Eutectic Solvents Job’s Method Ionic Liquids and Stability Constant
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Copper homeostasis and neurodegenerative diseases
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作者 Yuanyuan Wang Daidi Li +2 位作者 Kaifei Xu Guoqing Wang Feng Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3124-3143,共20页
Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is... Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7B),and the three copper chaperones ATOX1,CCS,and COX17.Disruptions in copper homeostasis can lead to either the deficiency or accumulation of copper in brain tissue.Emerging evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative disorders.However,the exact mechanisms underlying these processes are not known.Copper is a potent oxidant that increases reactive oxygen species production and promotes oxidative stress.Elevated reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial dysfunction.Reactive oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory pathways.Additionally,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell death.This study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease pathogenesis.By synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of hereditary and neuronal disorders,such as Wilson's disease,Menkes'disease,Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,Huntington's disease,and multiple sclerosis.Potential clinically significant therapeutic targets,including superoxide dismutase 1,D-penicillamine,and 5,7-dichloro-2-[(dimethylamino)methyl]-8-hydroxyquinoline,along with their associated therapeutic agents,are further discussed.Ultimately,we collate evidence that copper homeostasis may function in the underlying etiology of several neurodegenerative diseases and offer novel insights into the potential prevention and treatment of these diseases based on copper homeostasis. 展开更多
关键词 Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease Wilson's disease
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Role of copper chelating agents: between old applications and new perspectives in neuroscience
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作者 Rosalba Leuci Leonardo Brunetti +4 位作者 Vincenzo Tufarelli Marco Cerini Marco Paparella Nikola Puvača Luca Piemontese 《Neural Regeneration Research》 SCIE CAS 2025年第3期751-762,共12页
The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays a... The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays an important role in the central nervous system, where it is associated with glutamatergic signaling, and it is widely involved in inflammatory processes. Thus, diseases involving copper(Ⅱ) dyshomeostasis often have neurological symptoms, as exemplified by Alzheimer's and other diseases(such as Parkinson's and Wilson's diseases). Moreover, imbalanced copper ion concentrations have also been associated with diabetes and certain types of cancer, including glioma. In this paper, we propose a comprehensive overview of recent results that show the importance of these metal ions in several pathologies, mainly Alzheimer's disease, through the lens of the development and use of copper chelators as research compounds and potential therapeutics if included in multi-target hybrid drugs. Seeing how copper homeostasis is important for the well-being of animals as well as humans, we shortly describe the state of the art regarding the effects of copper and its chelators in agriculture, livestock rearing, and aquaculture, as ingredients for the formulation of feed supplements as well as to prevent the effects of pollution on animal productions. 展开更多
关键词 agriculture Alzheimer's disease CHELATORS copper feed supplements MULTI-TARGET
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Role of copper in central nervous system physiology and pathology
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作者 Martina Locatelli Cinthia Farina 《Neural Regeneration Research》 SCIE CAS 2025年第4期1058-1068,共11页
Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central ne... Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central nervous system.Central copper dysregulations have been evidenced in two genetic disorders characterized by mutations in the copper-ATPases ATP7A and ATP7B,Menkes disease and Wilson’s disease,respectively,and also in multifactorial neurological disorders such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and multiple sclerosis.This review summarizes current knowledge about the role of copper in central nervous system physiology and pathology,reports about unbalances in copper levels and/or distribution under disease,describes relevant animal models for human disorders where copper metabolism genes are dysregulated,and discusses relevant therapeutic approaches modulating copper availability.Overall,alterations in copper metabolism may contribute to the etiology of central nervous system disorders and represent relevant therapeutic targets to restore tissue homeostasis. 展开更多
关键词 ASTROCYTES central nervous system copper CUPRIZONE multiple sclerosis MYELIN neurodegenerative disorders
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外周血平均血小板体积/淋巴细胞计数(MPVLR)联合APACHE II评分对脓毒症患者预后的预测价值
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作者 郭宇琴 刘红玲 +2 位作者 陶武 王念 姚钰竹 《临床医学进展》 2025年第2期330-337,共8页
目的:探讨外周血平均血小板体积/淋巴细胞计数(MPVLR)联合APACHE II评分对脓毒症患者预后的预测价值。方法:采用回顾性队列研究方法,选择该院2020年8月至2023年8月收治的符合脓毒症3.0诊断标准的患者。根据脓毒症患者的28 d预后情况分... 目的:探讨外周血平均血小板体积/淋巴细胞计数(MPVLR)联合APACHE II评分对脓毒症患者预后的预测价值。方法:采用回顾性队列研究方法,选择该院2020年8月至2023年8月收治的符合脓毒症3.0诊断标准的患者。根据脓毒症患者的28 d预后情况分为生存组及死亡组。收集患者的临床资料及确诊脓毒症后24 h内血小板体积(MPV)、淋巴细胞(LYM)计数的最差值,并计算平均血小板体积/淋巴细胞计数(MPVLR)、APACHE II评分及SOFA评分。随后使用多因素Logistic回归分析,确定脓毒症患者预后的影响因素,再构建受试者工作特征曲线,评估各项指标对脓毒症患者预后的预测价值。结果:共纳入患者127例,生存组患者76例,死亡组患者51例。死亡组患者更易合并慢性阻塞性肺疾病,且平均血小板体积(MPV)、平均血小板体积/淋巴细胞计数(MPVLR)、APACHE II评分、SOFA评分、及年龄均高于生存组,且差异具有统计学意义(P Objective: To investigate the prognostic value of the mean platelet volume (MPV)-to-lymphocyte ratio (MPVLR) combined with the APACHE II score in predicting the outcomes of patients with sepsis. Methods: This retrospective study screened patients with sepsis who were hospitalized in our hospital, from August 2020 to August 2023 were included and categorized into the survival group and the non-survival group based on 28-day outcomes of sepsis patients. Clinical date and the worst of mean platelet volume (MPV), lymphocyte (LYM) count values within 24 hours of sepsis diagnosis were collected, MPVLR and APACHE II scores were calculated. Multifactorial logistic regression analysis was used to identify risk factors affecting the prognosis of sepsis patients, and then a subject operating characteristic curve (ROC) was constructed to assess the predictive value of each indicator on the prognosis of sepsis patients. Results: A total of 127 patients were included, with 76 in the survival group and 51 in the non-survival group. Patients in the non-survival group were more likely to have chronic obstructive pulmonary disease, and had significantly higher MPV, MPVLR, APACHE II scores, SOFA scores and age compared to the survival group (P < 0.05). In contrast, peripheral blood lymphocyte counts in the survival group were significantly higher than that in the non-survival group (P < 0.05). Multivariate logistic regression analysis showed that MPVLR and APACHE II scores were independent risk factors for 28-day mortality in sepsis patients (P < 0.05). Receiver operating characteristic curve (ROC) curve analysis showed that the area under the curve (AUC) values for MPVLR, APACHE II scores, and their combination were 0.840, 0.800, and 0.885, respectively. Notably, the MPVLR combined with the APACHE II score showed the best predictive value, with an AUC of 0.824. It demonstrated excellent predictive performance, achieving a sensitivity of 94.6% and a specificity of 82.4%. Conclusion: APACHE II scores and MPVLR are independent risk factors for 28-day mortality in sepsis patients, and their combined use provides higher predictive value. 展开更多
关键词 脓毒症 APACHE ii评分 血小板平均体积 淋巴细胞计数 血小板平均体积与淋巴细胞计数比值
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-N coupling magnetic characterization
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Reactive Oxygen Species (ROS) Generated on the Surface of (100)-Plane Grain-Oriented Copper Thin-Film
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作者 Ken Hirota Taika Maeda +4 位作者 Kazuhiko Tsukagoshi Yurika Taniguchi Hiroshi Kawakami Takashi Ozawa Masahiko Wada 《Materials Sciences and Applications》 2025年第1期27-45,共19页
This work aims to study the dependence of the antibacterial activity on the crystal plane of Cu. The generation of reactive oxygen species (ROS) on the thin film of Cu with grains oriented in the plane (100) was evalu... This work aims to study the dependence of the antibacterial activity on the crystal plane of Cu. The generation of reactive oxygen species (ROS) on the thin film of Cu with grains oriented in the plane (100) was evaluated by chemiluminescence (CL). The authors proposed the generation mechanism of these three ROS on the outermost surface consisting of Cu2O thin film, CuO layer and bulk Cu. 展开更多
关键词 copper Crystal Planes Antibacterial Activity Reactive Oxygen Species CHEMILUMINESCENCE
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Reconfiguration and Optimal Positioning of Multiple-Point Capacitors in a High-Voltage Distribution Network Using the NSGAII
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作者 Arouna Oloulade Richard Gilles Agbokpanzo +6 位作者 Maurel Richy Aza-Gnandji Hassane Ousseyni Ibrahim Moussa Gonda Eméric Tokoudagba Juliano Sétondji François-Xavier Fifatin Adolphe Moukengue Imano 《Open Journal of Applied Sciences》 2025年第2期501-516,共16页
The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively ... The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively applying mono-capacitor positioning, multiple positioning and reconfiguration processes using GA-based algorithms implemented in a Matlab environment. From the diagnostic study of this network, it was observed that a minimum voltage of 0.90 pu induces a voltage deviation of 5.26%, followed by active and reactive losses of 425.08 kW and 435.09 kVAR, respectively. Single placement with the NSGAII resulted in the placement of a 3000 kVAR capacitor at node 128, which proved to be the invariably neuralgic point. Multiple placements resulted in a 21.55% reduction in losses and a 0.74% regression in voltage profile performance. After topology optimization, the loss profile improved by 65.08% and the voltage profile improved by 1.05%. Genetic algorithms are efficient and effective tools for improving the performance of distribution networks, whose degradation is often dynamic due to the natural variability of loads. 展开更多
关键词 RECONFIGURATION Capacitor Bank NSGA ii Dynamic Network Degradation Distribution Network Reliability
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Metabolomic Changes in Mice Induced by Copper Exposure:Systematic Analysis and Exploration of Toxicity Mechanisms
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作者 Shuai Xiao Linqiang Gong +7 位作者 Shiyuan Zhao Xue Chu Fengfeng Li Yazhou Zhang Fangqiang Song Pei Jiang Gang Ding Shuai Tang 《Biomedical and Environmental Sciences》 2025年第1期106-118,共13页
Copper is one of the essential trace elements for living beings,influencing several critical processes like cellular energy production,antioxidant defense,communication within cells,and the functioning of enzymes[1].T... Copper is one of the essential trace elements for living beings,influencing several critical processes like cellular energy production,antioxidant defense,communication within cells,and the functioning of enzymes[1].The daily intake of copper is 0.7−3.0 mg/d,and copper homeostasis is strictly regulated by physiological processes,including duodenal and small intestinal uptake,blood transport,liver storage and release,and bile excretion,thereby maintaining copper homeostasis in the body[2],and many studies have confirmed that copper disorders in the body are associated with neurodegenerative,metabolic,and genetic diseases[3]. 展开更多
关键词 copper HOMEOSTASIS thereby
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基于NSGA-II的UPQC多目标PI控制器参数优化研究
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作者 黄雄 吴天杰 +4 位作者 陈锐忠 罗杰 林少佳 宋平平 刘剑 《电机与控制应用》 2025年第3期315-327,共13页
【目的】本文研究了基于非支配排序遗传算法II(NSGA-II)的统一电能质量调节器(UPQC)多目标比例积分(PI)控制器参数优化问题。UPQC作为一种重要的电力质量改善装置,能够有效抑制电网电压波动、谐波及不平衡等问题,但其性能依赖于控制器... 【目的】本文研究了基于非支配排序遗传算法II(NSGA-II)的统一电能质量调节器(UPQC)多目标比例积分(PI)控制器参数优化问题。UPQC作为一种重要的电力质量改善装置,能够有效抑制电网电压波动、谐波及不平衡等问题,但其性能依赖于控制器参数的合理配置。针对传统优化方法难以满足系统的多目标性能需求,且容易陷入局部最优的问题,本文提出了一种基于NSGA-II的多目标优化策略,旨在寻求一种能够同时优化谐波抑制、电压稳定性和动态响应速度的控制器参数配置方案。【方法】本文采用NSGA-II进行多目标优化,该算法通过快速非支配排序和拥挤度计算来实现多目标函数的全局优化。NSGA-II具有良好的全局搜索能力和快速收敛特性,因此优化UPQC控制器的参数时,能够快速而准确地找到最优解。在优化过程中,以谐波抑制、电压稳定性和动态响应速度作为主要优化目标,通过精确调整PI控制器参数,求得最优的控制策略。【结果】通过电网电压补偿仿真和直流、交流侧电压仿真来验证本文所提策略的有效性和准确性。在电网电压补偿仿真中,将本文策略与非线性比例积分-模型预测控制(PI-MPC)策略进行对比,本文所提策略实际补偿电压波形更趋于正弦曲线,且波形较为光滑平顺,谐波含量比非线性PI-MPC策略更小。在直流、交流侧电压仿真中,本文策略比其他策略的调节时间更短且超调量更低,在系统发生扰动时恢复时间更短,具有更强的鲁棒性。【结论】基于NSGA-II的PI控制器参数优化策略能够有效提升UPQC在复杂工况下的性能表现,提高系统的电能质量和响应效率。与传统方法相比,该优化策略不仅提升了电力质量,而且在动态响应过程中表现出更优的稳定性和更快速的调节能力。 展开更多
关键词 参数优化 比例积分控制器 非支配排序遗传算法ii 统一电能质量调节器 电能质量
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Effect of Nursing Interventions Based on APACHE II Scores on Gastrointestinal Function Recovery Time in Patients with Severe Pancreatitis
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作者 Yinfeng Wu 《Journal of Clinical and Nursing Research》 2025年第1期273-278,共6页
Objective: To explore the application effect of nursing interventions based on APACHE II scores in patients with severe pancreatitis and its impact on the recovery time of the gastrointestinal function. Methods: A tot... Objective: To explore the application effect of nursing interventions based on APACHE II scores in patients with severe pancreatitis and its impact on the recovery time of the gastrointestinal function. Methods: A total of 86 patients with severe pancreatitis treated in our hospital from March 2023 to March 2024 were selected. Using a random number table method, the patients were divided into a control group receiving conventional nursing care and a study group receiving nursing interventions based on APACHE II scores, with 43 patients in each group. The intervention effects of the two groups were compared. Results: The recovery time of gastrointestinal function in the study group was significantly shorter than that in the control group (P < 0.05). After the intervention, the quality of life scores in the study group was significantly higher than those in the control group (P < 0.05). The incidence of complications in the study group was significantly lower than in the control group (P < 0.05). Conclusion: Nursing interventions based on APACHE II scores can shorten gastrointestinal recovery time and reduce complications in patients with severe pancreatitis, contributing to improved quality of life. 展开更多
关键词 Severe pancreatitis APACHE ii score NURSING Gastrointestinal function
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Numerical Simulation of Flow and Temperature Distribution in a Bottom-Blown Copper Bath
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作者 Teng Xia Xiaohui Zhang +4 位作者 Ding Ma Zhi Yang Xinting Tong Yutang Zhao Hua Wang 《Fluid Dynamics & Materials Processing》 2025年第1期121-140,共20页
Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphas... Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphaseflow within the furnace.Understanding the flow structure and temperature distribution in this setup is crucial foroptimizing production.In this study,gas-liquid interactions,and temperature profiles under varying air-injectionconditions are examined by means of numerical simulation for a 3.2 m×20 m furnace.The results indicate that thehigh-velocity regions are essentially distributed near the lance within the reaction region and the flue gas outlet,while low-velocity regions are located close to the furnace walls on both side of the reaction region.Dead regionsappear in the sedimentation region,with gas velocities surpassing those of the molten phase.As the injection rateincreases from 0.50 to 0.80 Nm3/s,the stabilization time of the average liquid surface velocity decreases from 2.6 sto 1.9 s,exhibiting a similar trend to the gas holdup.During stabilization,the average liquid surface velocity risesfrom 0.505 to 0.702 m/s.The average turbulent kinetic energy(TKE)of the fluid in the molten bath increases from0.095 to 0.162 m^(2)/s^(2).The proportion of the area distribution with TKE greater than 0.10 m^(2)/s^(2) and the gas holdupat steady state both rise with an increase in the injection quantity.The maximum splashing height of the melt growsfrom approximately 0.756 to 1.154 m,with the affected area expanding from 14.239 to 20.498 m^(2).Under differentworking conditions with varying injection quantities,the average temperature changes in melt zone and flue gaszone of the furnace are small.The temperature in the melt and in the flue-gas zone spans the interval 1200℃–1257℃,and 1073℃–1121℃,respectively.The temperature distribution of the melt and flue gas reveals a patterncharacterized by elevated temperatures in the reaction zone,gradually transitioning to lower temperatures in thesedimentation region. 展开更多
关键词 copper smelting bottom-blown melting furnace flow characteristics temperature distribution numerical simulation
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Performance of stabilized copper mine tailings with freeze-thaw and wet-dry seasonal cycles
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作者 Uddav Ghimire Tejo V.Bheemasetti Hee-Jeong Kim 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1418-1428,共11页
Approximately 3.44 billion tons of copper mine tailings(MT)were produced globally in 2018 with an increase of 45%from 2010.Significant efforts are being made to manage these tailings through storage facilities,recycli... Approximately 3.44 billion tons of copper mine tailings(MT)were produced globally in 2018 with an increase of 45%from 2010.Significant efforts are being made to manage these tailings through storage facilities,recycling,and reuse in different industries.Currently,a large portion of tailings are managed through the tailing storage facilities(TSF)where these tailings undergo hydro-thermal-mechanical stresses with seasonal cycles which are not comprehensively understood.This study presents an investigative study to evaluate the performance of control and cement-stabilized copper MT under the influence of seasonal cycles,freeze-thaw(F-T)and wet-dry(W-D)conditions,representing the seasonal variability in the cold and arid regions.The control and cement-stabilized MT samples were subjected to a maximum of 12 F-T and 12 W-D cycles and corresponding micro-and-macro behavior was investigated through scanning electron microscope(SEM),volumetric strain(εvT,wet density(r),moisture content loss,and unconfined compressive strength(UCS)tests.The results indicated the vulnerability of Copper MT to 67%and 75%strength loss reaching residual states with 12 F-T and 8 W-D cycles,respectively.Whereas the stabilized MT retained 39%-55%and 16%-34%strength with F-T and W-D cycles,demonstrating increased durability.This research highlights the impact of seasonal cycles and corresponding strength-deformation characteristics of control and stabilized Copper MT in cold and arid regions. 展开更多
关键词 copper mine tailings(MT) Stabilization Seasonal cycles Cold and arid region
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一类II型偶长Z-互补序列对的构造
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作者 何颖 《应用数学进展》 2025年第2期62-68,共7页
文章以二进制互补对的核为基础,利用Turyn构造法得到一种长度为N=2α10β26γ(α,β,γ为非负整数)的Golay互补对(Golay Complementary Pair, GCP),在此基础上利用级联和删除函数得到长度为II型2N−2的偶长Z-互补对,并且它们非周期相关... 文章以二进制互补对的核为基础,利用Turyn构造法得到一种长度为N=2α10β26γ(α,β,γ为非负整数)的Golay互补对(Golay Complementary Pair, GCP),在此基础上利用级联和删除函数得到长度为II型2N−2的偶长Z-互补对,并且它们非周期相关函数和在零相关区外的幅值为4,丰富了II型偶长Z-互补序列对的数量。与已知传统的序列构造方法相比,文章提出了一种新的构造方法。Based on the kernel of binary complementary pairs, a Golay Complementary Pair (GCP) with a sequence length of N=2α10β26γ(and α,β,γare non-negative integers) was constructed by using Turyn Construction. On this basis, the Deletion Function and Cascading were used to obtain the Type II EB-ZCP with a length of 2N−2, and their aperiodic correlation functions and amplitudes outside the zero-correlation region were 4, which enriches the number of Type II EB-ZCP. Compared with the known traditional sequence construction methods, a new construction method is proposed. 展开更多
关键词 ii型Z-互补对 Golay互补对 零相关区 删除函数
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基于改进NSGA-II的综合能源系统多目标优化研究
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作者 宁童 黄伟 《上海电力大学学报》 2025年第1期28-34,共7页
针对可再生能源的不稳定性和波动性问题,传统的多目标优化算法在解决这类问题时,往往面临收敛速度慢、解集多样性不足,以及在高维问题中效率低下等挑战。为此,提出了一种改进的第二代非支配排序遗传算法(NSGA-II),专门用于含非凸约束的... 针对可再生能源的不稳定性和波动性问题,传统的多目标优化算法在解决这类问题时,往往面临收敛速度慢、解集多样性不足,以及在高维问题中效率低下等挑战。为此,提出了一种改进的第二代非支配排序遗传算法(NSGA-II),专门用于含非凸约束的综合能源系统多目标运行优化问题。该算法在传统综合能源系统中引入了电转气技术和多元储能模块,旨在克服传统优化算法的缺点,包括收敛速度慢、解集多样性不足和效率低下等问题。算例分析结果表明,所提算法可使运行总成本最多降低19.26%,碳排放量最多减少17.24%,从而验证了该算法的优越性和可靠性。 展开更多
关键词 综合能源系统 改进NSGA-ii 多目标优化 电转气
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A Type of Hopf Bifurcation in Models with Holling-II Type Multiple Sclerosis
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作者 Manhui He 《Journal of Applied Mathematics and Physics》 2025年第1期327-347,共21页
Multiple autoimmune diseases often exhibit a cyclic pattern of relapse and remission, with significant periods of loss of self-tolerance being interrupted by recurrent autoimmune events. In this article, we explore a ... Multiple autoimmune diseases often exhibit a cyclic pattern of relapse and remission, with significant periods of loss of self-tolerance being interrupted by recurrent autoimmune events. In this article, we explore a specific type of terminally differentiated regulatory T cell HLA−DR+TRegcells, and their application in existing autoimmune disease models. We also conduct an in-depth study on a multiple sclerosis model. This model incorporates a Holling-II type functional response mechanism. The focus of the study is to analyze whether the equilibrium points of the system have local asymptotic stability and determine the conditions for the existence of Hopf bifurcation. Furthermore, the direction of Hopf bifurcations and the stability of its periodic solutions can be analyzed through normal form theory and center manifold theorem. 展开更多
关键词 Multiple Sclerosis Model Holling-ii Type Functional Response Equilibrium Point STABILITY Hopf Bifurcation
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融合NSGA-II和CSA的多目标车间调度 被引量:2
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作者 杨青 席珍珍 +2 位作者 葛亮 林星宇 邢志超 《计算机工程与应用》 CSCD 北大核心 2024年第4期315-323,共9页
针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-do... 针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-dominated sorting genetic algorithms)和克隆选择(clonal selection algorithm,CSA)的改进算法INGCSA来解决此类问题。采用工件、加工机台和AGV三部分编码;引入非支配排序和目标函数值大小排序后总得分进行种群分层,从而有效地保留优秀个体;针对克隆后的种群,对不同等级的种群采取不同的变异概率,并对染色体进行内部交换与均匀交叉混合交换的基因重组,有效地提高了种群的多样性与防止陷入局部最优。通过三组对比实验,验证了该算法在探索最优解时,具有运行时间短、稳定性高和收敛性好等优点。 展开更多
关键词 NSGA-ii 克隆选择算法 任务调度 运输调度 自动引导车(AGV)
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基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II决策方法
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作者 杨威 李静 《工程数学学报》 CSCD 北大核心 2024年第3期525-539,共15页
针对属性权重完全未知或部分已知,属性值为区间毕达哥拉斯犹豫模糊数的多属性决策问题,提出了基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II法。首先给出区间毕达哥拉斯犹豫模糊数的区间形式的得分函数和精度函数,定义新的距离测... 针对属性权重完全未知或部分已知,属性值为区间毕达哥拉斯犹豫模糊数的多属性决策问题,提出了基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II法。首先给出区间毕达哥拉斯犹豫模糊数的区间形式的得分函数和精度函数,定义新的距离测度。然后基于区间毕达哥拉斯犹豫模糊数的模糊因子、直觉因子和幅度因子,给出熵和交叉熵公式,并证明其性质,提出了基于熵和交叉熵确定属性权重的方法。最后提出了区间毕达哥拉斯犹豫模糊环境下的改进的ELECTRE II法,利用综合优势值对方案进行排序,并通过算例和比较分析验证了该方法的可行性和有效性。 展开更多
关键词 多属性决策 区间毕达哥拉斯犹豫模糊集 交叉熵 ELECTRE ii
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