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Impact of Well Thickness on Static and Dynamic Behavior of InGaN Light-emitting Diode with Single Quantum Well
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作者 CHEN Guichu HE Longfei PENG Kun 《发光学报》 北大核心 2026年第2期314-320,共7页
In this paper,we present a circuit model of single-quantum-well InGaN/GaN light-emitting diodes based on the standard rate equations.Two rate equations describe carrier transport processes occurring in sep-arate confi... In this paper,we present a circuit model of single-quantum-well InGaN/GaN light-emitting diodes based on the standard rate equations.Two rate equations describe carrier transport processes occurring in sep-arate confinement heterostructure and quantum well respectively,and the third equation describes the varied photons in quantum well.By using the presented model,impacts of quantum well thickness on the static and dynamic performances are investigated.Simulated results show that LED with 4 nm well exhibits better lightcurrent(L-I)performance,but LED with 3 nm well presents wider 3 dB modulation bandwidth.It reveals that high carrier density in quantum well is detrimental to the static performance,but beneficial to the dynamic performance. 展开更多
关键词 single quantum well rate equations circuit model L-I performance modulation bandwidth
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Quantum Secure Multiparty Computation:Bridging Privacy,Security,and Scalability in the Post-Quantum Era
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作者 Sghaier Guizani Tehseen Mazhar Habib Hamam 《Computers, Materials & Continua》 2026年第4期1-25,共25页
The advent of quantum computing poses a significant challenge to traditional cryptographic protocols,particularly those used in SecureMultiparty Computation(MPC),a fundamental cryptographic primitive for privacypreser... The advent of quantum computing poses a significant challenge to traditional cryptographic protocols,particularly those used in SecureMultiparty Computation(MPC),a fundamental cryptographic primitive for privacypreserving computation.Classical MPC relies on cryptographic techniques such as homomorphic encryption,secret sharing,and oblivious transfer,which may become vulnerable in the post-quantum era due to the computational power of quantum adversaries.This study presents a review of 140 peer-reviewed articles published between 2000 and 2025 that used different databases like MDPI,IEEE Explore,Springer,and Elsevier,examining the applications,types,and security issues with the solution of Quantum computing in different fields.This review explores the impact of quantum computing on MPC security,assesses emerging quantum-resistant MPC protocols,and examines hybrid classicalquantum approaches aimed at mitigating quantum threats.We analyze the role of Quantum Key Distribution(QKD),post-quantum cryptography(PQC),and quantum homomorphic encryption in securing multiparty computations.Additionally,we discuss the challenges of scalability,computational efficiency,and practical deployment of quantumsecure MPC frameworks in real-world applications such as privacy-preserving AI,secure blockchain transactions,and confidential data analysis.This review provides insights into the future research directions and open challenges in ensuring secure,scalable,and quantum-resistant multiparty computation. 展开更多
关键词 quantum computing secure multiparty computation(MPC) post-quantum cryptography(PQC) quantum key distribution(QKD) privacy-preserving computation quantum homomorphic encryption quantum network security federated learning blockchain security quantum cryptography
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Random State Approach to Quantum Computation of Electronic-Structure Properties
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作者 Yiran Bai Feng Xiong Xueheng Kuang 《Chinese Physics Letters》 2026年第1期89-104,共16页
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v... Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials. 展开更多
关键词 periodic materials random state circuit random state quantum algorithms electronic structure properties density states aperiodic materials quantum algorithms quantum computation
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Double Wilczek–Zee connection and mixed-state quantum geometric tensor
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作者 Xiaoguang Wang Xiao-Ming Lu +2 位作者 Jing Liu Wenkui Ding Libin Fu 《Chinese Physics B》 2026年第2期300-305,共6页
The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor... The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor(QGT),another important concept in the field of quantum geometry.The DWZC is Hermitian with respect to the two integer indices,just like the original Hermitian WZC.Based on the symmetric logarithmic derivative operator,we propose a mixed-state quantum geometric tensor.Using the symmetric properties of the DWZC,we find that the real part of the QGT is connected to the real part of the DWZC and the square of eigenvalue differences of the density matrix,whereas the imaginary part can be given in terms of the imaginary part of the DWZC and the cube of the eigenvalue differences.For density matrices with full rank or no full rank,the QGT can be given in terms of real and imaginary parts of the DWZC. 展开更多
关键词 quantum geometry Wilczek–Zee connection quantum geometric tensor
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Broadband Telecom Single-Photon Emissions from InAs/InP Quantum Dots Grown by MOVPE Droplet Epitaxy
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作者 Shichen Zhang Li Liu +6 位作者 Kai Guo Xingli Mu Yuanfei Gao Junqi Liu Fengqi Liu Quanyong Lu Zhiliang Yuan 《Chinese Physics Letters》 2026年第1期37-43,共7页
The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon ... The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications. 展开更多
关键词 development quantum materials broadband telecom single photon emissions MOVPE droplet epitaxy InAs InP quantum dots microcavity enhancement quantum dots qds using information technologyalthough
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A Quantum-Inspired Algorithm for Clustering and Intrusion Detection
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作者 Gang Xu Lefeng Wang +5 位作者 Yuwei Huang Yong Lu Xin Liu Weijie Tan Zongpeng Li Xiu-Bo Chen 《Computers, Materials & Continua》 2026年第4期1180-1215,共36页
The Intrusion Detection System(IDS)is a security mechanism developed to observe network traffic and recognize suspicious or malicious activities.Clustering algorithms are often incorporated into IDS;however,convention... The Intrusion Detection System(IDS)is a security mechanism developed to observe network traffic and recognize suspicious or malicious activities.Clustering algorithms are often incorporated into IDS;however,conventional clustering-based methods face notable drawbacks,including poor scalability in handling high-dimensional datasets and a strong dependence of outcomes on initial conditions.To overcome the performance limitations of existing methods,this study proposes a novel quantum-inspired clustering algorithm that relies on a similarity coefficient-based quantum genetic algorithm(SC-QGA)and an improved quantum artificial bee colony algorithm hybrid K-means(IQABC-K).First,the SC-QGA algorithmis constructed based on quantum computing and integrates similarity coefficient theory to strengthen genetic diversity and feature extraction capabilities.For the subsequent clustering phase,the process based on the IQABC-K algorithm is enhanced with the core improvement of adaptive rotation gate and movement exploitation strategies to balance the exploration capabilities of global search and the exploitation capabilities of local search.Simultaneously,the acceleration of convergence toward the global optimum and a reduction in computational complexity are facilitated by means of the global optimum bootstrap strategy and a linear population reduction strategy.Through experimental evaluation with multiple algorithms and diverse performance metrics,the proposed algorithm confirms reliable accuracy on three datasets:KDD CUP99,NSL_KDD,and UNSW_NB15,achieving accuracy of 98.57%,98.81%,and 98.32%,respectively.These results affirm its potential as an effective solution for practical clustering applications. 展开更多
关键词 Intrusion detection CLUSTERING quantum artificial bee colony algorithm K-MEANS quantum genetic algorithm
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Hybridization Gap and Edge States in Strained-Layer InAs/In_(0.5)Ga_(0.5)Sb Quantum Spin Hall Insulator
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作者 Wenfeng Zhang Peizhe Jia +4 位作者 Wen-kai Lou Xinghao Wang Shaokui Su Kai Chang Rui-Rui Du 《Chinese Physics Letters》 2026年第1期179-183,共5页
The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges be... The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges between 0.2 and 0.4.This enhancement prompts a critical question:to what extent can quantum wells(QWs)be strained while still preserving the fundamental QSHI phase?In this study,we demonstrate the controlled molecular beam epitaxial growth of highly strained-layer QWs with an indium composition of x=0.5.These structures possess a substantial compressive strain within the In_(0.5)Ga_(0.5)Sb QW.Detailed crystal structure analyses confirm the exceptional quality of the resulting epitaxial films,indicating coherent lattice structures and the absence of visible dislocations.Transport measurements further reveal that the QSHI phase in InAs/In_(0.5)Ga_(0.5)Sb QWs is robust and protected by time-reversal symmetry.Notably,the edge states in these systems exhibit giant magnetoresistance when subjected to a modest perpendicular magnetic field.This behavior is in agreement with the𝑍2 topological property predicted by the Bernevig–Hughes–Zhang model,confirming the preservation of topologically protected edge transport in the presence of enhanced bulk strain. 展开更多
关键词 strained layer quantum spin hall insulators qshis InAs Ga Sb edge states quantum wells qws be controlled molecular beam epitaxial growth hybridization gap quantum spin Hall insulator
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YOLOv10-HQGNN:A Hybrid Quantum Graph Learning Framework for Real-Time Faulty Insulator Detection
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作者 Nghia Dinh Vinh Truong Hoang +6 位作者 Viet-Tuan Le Kiet Tran-Trung Ha Duong Thi Hong Bay Nguyen Van Hau Nguyen Trung Thien Ho Huong Kittikhun Meethongjan 《Computers, Materials & Continua》 2026年第3期1747-1769,共23页
Ensuring the reliability of power transmission networks depends heavily on the early detection of faults in key components such as insulators,which serve both mechanical and electrical functions.Even a single defectiv... Ensuring the reliability of power transmission networks depends heavily on the early detection of faults in key components such as insulators,which serve both mechanical and electrical functions.Even a single defective insulator can lead to equipment breakdown,costly service interruptions,and increased maintenance demands.While unmanned aerial vehicles(UAVs)enable rapid and cost-effective collection of high-resolution imagery,accurate defect identification remains challenging due to cluttered backgrounds,variable lighting,and the diverse appearance of faults.To address these issues,we introduce a real-time inspection framework that integrates an enhanced YOLOv10 detector with a Hybrid Quantum-Enhanced Graph Neural Network(HQGNN).The YOLOv10 module,fine-tuned on domainspecific UAV datasets,improves detection precision,while the HQGNN ensures multi-object tracking and temporal consistency across video frames.This synergy enables reliable and efficient identification of faulty insulators under complex environmental conditions.Experimental results show that the proposed YOLOv10-HQGNN model surpasses existing methods across all metrics,achieving Recall of 0.85 and Average Precision(AP)of 0.83,with clear gains in both accuracy and throughput.These advancements support automated,proactive maintenance strategies that minimize downtime and contribute to a safer,smarter energy infrastructure. 展开更多
关键词 Object detection GNN QGNN HQGNN quantum YOLO power quality
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A Cross-Band Quantum Light Source Based on Spontaneous Four-Wave Mixing in a Shallow-Ridge Silicon Waveguide
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作者 Yijia Wang Qirui Ren +2 位作者 Zhanping Jin Yidong Huang Wei Zhang 《Chinese Physics Letters》 2026年第1期64-70,共7页
To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.T... To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks. 展开更多
关键词 photon pair generation shallow ridge silicon waveguide spontaneous four wave mixing optical fiber networks adjusting ridge widthenabling cross band quantum light source broadband photon pair generation waveguide dispersion
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供应-加工-配送模式下低值医用耗材智能管理的研究
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作者 连蕊 郑福雪 +6 位作者 田君叶 谭艳芬 宋亚静 韩宁 李妍 蒙景雯 曾镇罡 《中华护理杂志》 北大核心 2026年第3期394-400,共7页
目的探索基于供应-加工-配送(supply-processing-distribution,SPD)的低值医用耗材智能管理模式及实施效果,为提升医院耗材精细化管理水平提供参考。方法采用历史对照,将北京市某三级甲等综合医院试点病房常用低值医用耗材纳入管理,其中... 目的探索基于供应-加工-配送(supply-processing-distribution,SPD)的低值医用耗材智能管理模式及实施效果,为提升医院耗材精细化管理水平提供参考。方法采用历史对照,将北京市某三级甲等综合医院试点病房常用低值医用耗材纳入管理,其中2024年4—11月的低值医用耗材纳入智能管理组,采用基于SPD的低值医用耗材智能管理模式;2023年3—11月的低值医用耗材纳入常规管理组,采用传统的医用耗材管理模式。比较两组低值医用耗材帐物相符率,科室低值医用耗材管理时间(申请、领取、盘存、盘点)、过期预警率、计费错误发生率、信息登记合格率、可追溯率及护理人员满意度的差异。结果智能管理组的低值医用耗材账物相符率平均值为99.33%,常规管理组平均值为70.04%(P<0.001)。智能管理组的科室低值医用耗材管理时间(申请、领取、盘存、盘点)低于常规管理组(P<0.001)。智能管理组的低值医用耗材信息登记合格率和可追溯率均为100%,高于常规管理组的94.30%、83.05%(P<0.001)。智能管理组的低值医用耗材过期预警率和计费错误发生率均为0,低于常规管理组的3.61%、7.00%(P<0.001)。护士满意度方面,智能管理组的护理人员满意度总分为3(3,4)分,高于常规管理组的3(2,4)分(P=0.007)。结论与常规医用耗材管理模式相比,基于SPD的低值医用耗材管理模式能够提升工作效率、降低耗材管理不良事件的发生,提高护理人员满意度。 展开更多
关键词 供应-加工-配送 医用耗材 低值耗材 护理管理研究
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安全科学范式运演机制:基于安全-Ⅰ、安全-Ⅱ、安全-Ⅲ的思维辨析
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作者 佟瑞鹏 王益艳 +3 位作者 武琪 毛颖 许素睿 安宇 《中国安全科学学报》 北大核心 2026年第1期7-16,共10页
为阐释安全-Ⅰ、安全-Ⅱ、安全-Ⅲ的本质差异,明确安全科学范式的运演机制,推动安全科学作为一门科学学科持续发展,运用文献综述法与比较分析法,从认识论和方法论维度解析三者的理论差异,进而从科学哲学视角论述安全科学范式的构建与转... 为阐释安全-Ⅰ、安全-Ⅱ、安全-Ⅲ的本质差异,明确安全科学范式的运演机制,推动安全科学作为一门科学学科持续发展,运用文献综述法与比较分析法,从认识论和方法论维度解析三者的理论差异,进而从科学哲学视角论述安全科学范式的构建与转换,澄清三者的范式定位。结果表明:安全-Ⅰ代表着重视因果关系的传统事故致因理论或模型,安全-Ⅱ是强调从正面视角研究安全问题的韧性理论方法,安全-Ⅲ则是基于系统理论及控制论的系统型事故致因模型。安全科学范式由一体四面构成,包括无范式阶段、范式建立阶段、常规科学研究阶段、范式危机以及范式转换阶段,当前安全科学范式以事故致因理论为主导,处于常规科学研究阶段,虽然存在范式危机现象,但尚未进入范式转换时期。安全-Ⅰ和安全-Ⅲ是事故致因理论范式中的研究内容,安全-Ⅱ的信念和研究视角发生了转变,可视为安全科学新的研究方向,但尚未成为新范式。未来安全科学范式的发展有3种形式,需在新技术的引领下持续实践和探索。 展开更多
关键词 安全科学范式 运演机制 安全- 安全- 安全- 范式转换
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基于弹簧-质量-阻尼模型的单环闭式脉动热管传热特性
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作者 战洪仁 刘德彬 +4 位作者 王立鹏 刘东灵 纪柏辰 刘鹏 吴旻 《化学工程》 北大核心 2026年第2期45-50,共6页
为探究单环闭式脉动热管的传热性能,使用理论推导获得脉动热管内两液柱系统振动方程,建立一个考虑气液相变的单环闭式脉动热管液柱振荡运动的弹簧-质量-阻尼模型。基于该模型,得到在弹性系数、质量等参数发生非线性变化下的单环闭式脉... 为探究单环闭式脉动热管的传热性能,使用理论推导获得脉动热管内两液柱系统振动方程,建立一个考虑气液相变的单环闭式脉动热管液柱振荡运动的弹簧-质量-阻尼模型。基于该模型,得到在弹性系数、质量等参数发生非线性变化下的单环闭式脉动热管的传热特性。并进行实验研究,验证该数学模型的正确性。结果表明:充液率为60%、加热功率为60 W时,脉动热管传热性能最好。脉动热管的启动时间与混沌特性呈正相关,混沌特性与传热特性呈正相关。 展开更多
关键词 弹簧-质量-阻尼模型 振动方程 非线性 传热性能 混沌特性
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鄂尔多斯盆地奥陶系盐下层系构造-沉积分异与烃源岩-储层分布规律
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作者 苏中堂 徐哲博 +6 位作者 魏柳斌 师平平 张雷 任军峰 任静 吴浩文 朱梦涵 《石油与天然气地质》 北大核心 2026年第1期64-80,共17页
盐下层系内碳酸盐岩-蒸发岩体系是全球油气增储上产的重点领域,其源-储组合样式及分布规律成为制约油气勘探的关键。鄂尔多斯盆地奥陶系盐下碳酸盐岩-蒸发岩体系的烃源岩与储层发育分布规律研究表明:①多级次“隆-坳”格局控制了沉积底... 盐下层系内碳酸盐岩-蒸发岩体系是全球油气增储上产的重点领域,其源-储组合样式及分布规律成为制约油气勘探的关键。鄂尔多斯盆地奥陶系盐下碳酸盐岩-蒸发岩体系的烃源岩与储层发育分布规律研究表明:①多级次“隆-坳”格局控制了沉积底形差异,古气候的干湿变迁改变了古海洋环境条件,导致沉积分异,进而形成了不同的碳酸盐岩-蒸发岩沉积序列,发育不同的烃源岩和储层。②古隆起与次级隆起区主要发育干旱气候期的泥质白云岩烃源岩,古坳陷内发育湿润气候期的泥晶灰岩烃源岩。③同期古隆起与次级隆起带通常发育颗粒滩沉积,亦为底栖生物有利栖息区,是气候由湿润转向干旱过程中高盐度卤水渗透回流的优势区带,易发生白云石化作用,控制了晶粒白云岩、颗粒白云岩、微生物白云岩和斑状白云岩储层的分布。④构造与沉积分异作用控制了碳酸盐岩-蒸发岩体系烃源岩与储层的分布规律,中央古隆起及其周缘斜坡带与邻近古坳陷的乌审旗隆起及神木-米脂低隆发育有效源-储组合,是盐下层系油气勘探的有利地带。 展开更多
关键词 古气候 构造-沉积分异 碳酸盐岩-蒸发岩体系 白云岩 深层-超深层 马家沟组 奥陶系 鄂尔多斯盆地
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基于麻黄-杏仁药对治疗哮喘大鼠的药动学-药效学模型探究
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作者 李文宏 饶倩 +5 位作者 陈林林 谢金根 高文军 杨添翼 田佳玉 肖雄 《中国医院药学杂志》 北大核心 2026年第1期11-16,共6页
目的:观察麻黄-杏仁药对中主要有效成分和哮喘相关效应指标的经时变化并建立药动学-药效学(pharmacokineticpharmacodynamic,PK-PD)结合模型,为该药对的生物学机制分析提供参考。方法:采用2%氯化乙酰胆碱和0.4%磷酸组胺等体积混合液诱... 目的:观察麻黄-杏仁药对中主要有效成分和哮喘相关效应指标的经时变化并建立药动学-药效学(pharmacokineticpharmacodynamic,PK-PD)结合模型,为该药对的生物学机制分析提供参考。方法:采用2%氯化乙酰胆碱和0.4%磷酸组胺等体积混合液诱发大鼠支气管哮喘,ELISA法检测各时间点组织匀浆中与哮喘相关的效应指标(cAMP、胞浆钙离子、IL-2、IL-6、IFN-γ)的含量。应用主成分分析法对有效成分及效应指标进行整合;采用s型E_(max)函数分别建立整合F_(PK)与整合分泌效应指标(F_(PD1))和整合所有效应指标(F_(PD2))的PK-PD结合模型。结果:药效学试验结果表明,麻黄-杏仁药对可以显著升高各个时间点的cAMP、IL-2、IFN-γ水平(P<0.05或P<0.01),显著降低各个时间点的胞浆钙离子、IL-6水平(P<0.01)。PK-PD结合结果表明,整合F_(PK)与所有效应指标(F_(PD2))结合后的各参数的变异系数最小,拟合的更好。结论:麻黄-杏仁药对对具有控制或改善哮喘的作用;用整合PK-PD探究中药整体药动药效可能更具优越性,为效价评估、给药方案、用药安全提供参考。 展开更多
关键词 哮喘 麻黄-杏仁药对 药动学-药效学结合模型
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1-甲基-2,4-环己二胺合成催化剂研究进展
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作者 李贵贤 孔成荣 +8 位作者 陈光 李卫俊 王小伟 魏孔祥 刘耀宗 夏继冲 王首登 季东 李红伟 《石油学报(石油加工)》 北大核心 2026年第1期86-95,共10页
1-甲基-2,4-环己二胺(MCHD)是一种具有高附加值的化工产品,是生产氢化甲苯二异氰酸酯(HTDI)的关键原料,同时其在医药、高端涂料、功能分子材料领域具有优异的应用价值,市场需求量巨大。首先对MCHD催化合成工艺进行分析,重点研究了二硝... 1-甲基-2,4-环己二胺(MCHD)是一种具有高附加值的化工产品,是生产氢化甲苯二异氰酸酯(HTDI)的关键原料,同时其在医药、高端涂料、功能分子材料领域具有优异的应用价值,市场需求量巨大。首先对MCHD催化合成工艺进行分析,重点研究了二硝基甲苯(DNT)一步加氢法和甲苯二胺(TDA)加氢法的工艺流程、反应机理及各自的优劣势。综述了当前TDA氢化制MCHD过程中所涉及的加氢催化剂研究进展,发现贵金属催化剂,尤其是钌(Ru)和铑(Rh)催化剂,凭借其高活性和高选择性,成为目前MCHD合成过程中性能最优的催化剂;分析了催化剂的各种改性策略,例如通过引入稀土金属、碱性金属氧化物等手段对载体进行改性,以调节酸性位点的分布,可进一步提高催化剂的加氢性能,同时探讨了贵金属催化体系下的溶剂效应。总结了当前催化加氢法制MCHD工艺中存在的挑战,如催化剂成本高昂、反应条件苛刻、副产物难以控制等;并基于前人研究成果和课题组的前期研究基础,提出了切实可行的研究方向和思路。通过对现有研究报道的全面综述和科学分析,旨在为MCHD的工业化生产提供有价值的参考。 展开更多
关键词 甲苯二胺 催化加氢 1-甲基-2 4-环己二胺 金属催化剂 高选择性
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8,8′-亚甲基双射干苷元磺酸钠滴眼液的含量测定及有关物质的初步研究
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作者 陈帅 罗森 +5 位作者 汤依娜 罗恒 宁楠 赖明华 张磊 袁崇均 《华西药学杂志》 北大核心 2026年第1期88-92,共5页
目的建立8,8′-亚甲基双射干苷元磺酸钠(BXYW)滴眼液含量测定和有关物质限量的检测方法,并对有关物质进行初步研究。方法采用HPLC法检测BXYW滴眼液中BXYW的含量和有关物质限量,并采用超高效液相色谱-四级杆-飞行时间串联质谱法分析和推... 目的建立8,8′-亚甲基双射干苷元磺酸钠(BXYW)滴眼液含量测定和有关物质限量的检测方法,并对有关物质进行初步研究。方法采用HPLC法检测BXYW滴眼液中BXYW的含量和有关物质限量,并采用超高效液相色谱-四级杆-飞行时间串联质谱法分析和推导其有关物质的结构。结果含量测定方法的精密度、稳定性、重复性良好;平均加样回收率为99.70%,RSD=0.84%(n=6)。3批样品的含量分别为标示量的98.58%、98.34%、98.42%,有关物质的含量均低于2.0%,符合规定。质谱检测显示:BXYW滴眼液中的4个有关物质,均为BXYW异构或裂解而来。结论所用含量测定方法简便、快捷,可用于BXYW滴眼液的质量控制;有关物质的研究为药物的进一步研发奠定了基础,同时也为其他双黄酮化合物的合成提供了理论依据和解析思路。 展开更多
关键词 射干苷 8 8′-亚甲基射干苷元磺酸钠 滴眼液 含量测定 超高效液相色谱-四级杆-飞行时间串联质谱 双黄酮 有关物质
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水热合成ZSM-22封装Ni及选择性催化炔醇加氢
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作者 王学林 毕文涛 +2 位作者 曲炜 王从新 田志坚 《化工进展》 北大核心 2026年第1期247-257,共11页
以硅溶胶为硅源,1,6-己二胺为有机模板剂,氢氧化钾为碱源,硝酸镍为镍源,四乙烯五胺为有机胺配体,ZSM-22分子筛为晶种,采用水热法以及后续的焙烧和还原合成了Ni负载量为0.06%~0.34%的ZSM-22分子筛封装Ni催化剂(Ni@ZSM-22)。采用X射线衍射... 以硅溶胶为硅源,1,6-己二胺为有机模板剂,氢氧化钾为碱源,硝酸镍为镍源,四乙烯五胺为有机胺配体,ZSM-22分子筛为晶种,采用水热法以及后续的焙烧和还原合成了Ni负载量为0.06%~0.34%的ZSM-22分子筛封装Ni催化剂(Ni@ZSM-22)。采用X射线衍射、N2物理吸附、扫描电子显微镜、透射电子显微镜、X射线光电子能谱和H_(2)-程序升温还原表征了催化剂的物相、织构性质、Ni颗粒尺寸分布和落位。结果表明,样品均具有结晶度良好的ZSM-22分子筛相、相互穿插的梭形棒形貌,粒径分布均匀的高分散Ni颗粒被封装在分子筛晶粒的内部,85%以上Ni颗粒粒径小于2nm,Ni物种以金属态Ni^(0)和氧化态Ni^(δ+)(Ni—O—Si)两种形式共存。考察了催化剂的1,4-丁炔二醇加氢性能,催化剂上主产物是1,4-丁烯二醇,其中顺式烯醇占烯醇总量的94%以上。结合表征结果和产物分布,认为优异的烯醇选择性与ZSM-22分子筛孔道的空间限域作用以及Ni^(δ+)的存在有关。 展开更多
关键词 水热 分子筛 封装 催化剂 1 4-丁炔二醇 加氢 1 4-丁烯二醇
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龙门山褶皱冲断带剥蚀-沉积作用和先存断层结构砂箱物理模拟
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作者 邓宾 刘恣君 +8 位作者 马华灵 胡欣 郭虹兵 张本健 张旋 何宇 涂国煜 何泽亮 张小兵 《成都理工大学学报(自然科学版)》 北大核心 2026年第1期1-17,共17页
褶皱冲断带-前陆盆地系统普遍经历复杂浅表构造剥蚀-沉积作用过程,且受控于岩石地层展布和先存构造等因素,从而具有复杂的三维空间构造变形特征与演化过程。本文以青藏高原东缘龙门山褶皱冲断带-川西前陆盆地系统为原型,基于砂箱物理模... 褶皱冲断带-前陆盆地系统普遍经历复杂浅表构造剥蚀-沉积作用过程,且受控于岩石地层展布和先存构造等因素,从而具有复杂的三维空间构造变形特征与演化过程。本文以青藏高原东缘龙门山褶皱冲断带-川西前陆盆地系统为原型,基于砂箱物理模拟实验手段,设计了先存断裂和软弱岩层为控制因素的实验模型。对实验结果的构造变形特征进行解剖,探讨前陆冲断带不同位置的构造演化序列和埋深-沉降过程。研究结果表明:构造剥蚀-沉积作用导致冲断带后缘断层多期次活化,先存断层周缘区域属于构造薄弱带,在晚期构造挤压过程中先存断裂优先发生活化并形成反转构造。软弱滑脱层会导致应变集中滑脱效应,位于滑脱层附近的先存断层带更易形成复杂多样的反转构造。前陆冲断带不同位置的剥蚀抬升-埋深沉降史具有显著的差异性,冲断带上盘物质伴随挤压冲断发生微弱的埋深沉降,前陆盆地在冲断负载过程中发生快速和持续的埋深增温过程。龙门山山前隐伏构造带存在有利于油气聚集的反转冲起构造变形带。 展开更多
关键词 褶皱冲断带 青藏高原东缘 剥蚀-沉积作用 先存断层 反转构造 埋深-沉降史
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基于GC-O-MS的酸凝、酶凝奶酪挥发性风味比较及氨基酸含量分析
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作者 徐颖 王欢 +1 位作者 荣良燕 李儒仁 《中国乳品工业》 北大核心 2026年第2期36-43,共8页
为探讨中西方奶酪风味差异,文章采用感官评价结合气相色谱-嗅闻-质谱(Gas chromatography-olfactometry-mass spectrometry,GC-O-MS)技术,检测并比较了4种奶酪样品(SNL、CNL、WTB、ZNL)的挥发性风味物质及游离氨基酸含量。结果表明,共... 为探讨中西方奶酪风味差异,文章采用感官评价结合气相色谱-嗅闻-质谱(Gas chromatography-olfactometry-mass spectrometry,GC-O-MS)技术,检测并比较了4种奶酪样品(SNL、CNL、WTB、ZNL)的挥发性风味物质及游离氨基酸含量。结果表明,共检测到47种挥发性化合物,其中SNL和CNL分别含有24种和25种,WTB和ZNL分别含有16种和11种。SNL氨基酸含量最高,其次为CNL、WTB和ZNL。分析表明,ZNL具有显著的奶香、果香和烤面包香气,且酸属性得分较低,使其在整体香气平衡与协调上表现优异,喜好度评分最高。文章通过系统分析不同奶酪的挥发性化合物及氨基酸成分,为中西方奶酪的风味特征提供了数据支持,也为未来的产品开发和市场定位提供参考。 展开更多
关键词 奶酪 感官评价 气相色谱-嗅闻-质谱技术 挥发性风味物质
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