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The Immunomodulatory,Anti-Tumor,and Metabolic Regulatory Effects of Fraction D of Polysaccharide from Grifola frondosa:Clinical Experiments and Mechanistic Insights
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作者 Nurfarih Hanna Mohd Zarif Fikri Bin Mohd +1 位作者 Muhammad Nabil Fikri Bin Mohd Nurfarazuna Binti Mohd Fadrol 《Proceedings of Anticancer Research》 2026年第1期84-93,共10页
Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical eff... Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential. 展开更多
关键词 Grifola frondosa Maitake polysaccharide Fraction d Immune modulation Adjunctive cancer therapy Glycemic control Lipid metabolism Clinical trial Mechanism of action
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High-temperature characteristics of SiC module and 100 kW SiC AC–DC converter at a junction temperature of 180 ℃
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作者 Juanjuan Lu Zhe Zhou +3 位作者 Jianhong Hao Yi Hao Hao Zhang Ruixiang Hao 《Global Energy Interconnection》 2019年第6期522-531,共10页
High-temperature,high-power converters have gained importance in industrial applications given their ability to operate in adverse environments,such as in petroleum exploration,multi-electric aircrafts,and electric ve... High-temperature,high-power converters have gained importance in industrial applications given their ability to operate in adverse environments,such as in petroleum exploration,multi-electric aircrafts,and electric vehicles.SiC metaloxide-semiconductor field-effect transistor(MOSFET),a new,wide bandgap,high-temperature device,is the key component of these converters.In this study,the static and dynamic characteristics of the SiC MOSFET,half-bridge module,are investigated at the junction temperature of 180℃.A simplified experimental method is then proposed pertaining to the power operation of the SiC module at 180℃.This method is based on the use of a thermal resistance test platform and is proven convenient for the study of heat dissipation characteristics.The high-temperature characteristics of the module are verified based on the conducted experiments.Accordingly,a 100 kW high-temperature converter is built,and the test results show that the SiC converter can operate at a junction temperature of 180℃in a stable manner in compliance with the requirements of high-temperature,high-power applications. 展开更多
关键词 SiC MOSFET module Static and dynamic characteristics Power operation experimental method Heat dissipation characteristics SiC AC-dC converter
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基于串联型DC module的光伏发电系统研究 被引量:3
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作者 张琦 孙向东 +2 位作者 钟彦儒 吴迎丰 张凯 《西安理工大学学报》 CAS 北大核心 2009年第4期410-414,共5页
提出了一种基于串联型直流功率单元(DC module)电路的光伏发电系统,讨论了采用单端反激变换器实现的DC module电路。由于反激变换器用于升压变换时变压器原边电流较大,当并联使用时效率较低,为了减小DC module电路升压压力,提高每组变... 提出了一种基于串联型直流功率单元(DC module)电路的光伏发电系统,讨论了采用单端反激变换器实现的DC module电路。由于反激变换器用于升压变换时变压器原边电流较大,当并联使用时效率较低,为了减小DC module电路升压压力,提高每组变换器能量传输效率,采用串联形式的DC module电路,且每组DC module电路使用独立的最大功率追踪算法,由此组成的光伏发电系统提高了DC module电路的升压效率,且可以实现每块光伏电池板的最大功率点跟踪,解决了不同光照(阴影)、不同规格以及不同朝向等因素引起的失配问题。实验结果表明,当一路或多路电路中的电池板受到阴影影响时,各路电池板在控制器的作用下仍然工作在各自的最大功率点处。 展开更多
关键词 直流功率单元 单端反激变换器 光伏发电系统
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Monolithically Integrated Laser Diode and Electroabsorption Modulator with Dual-Waveguide Spot-Size Converter Output
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作者 侯廉平 王圩 +4 位作者 冯文 朱洪亮 周帆 王鲁峰 边静 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1094-1099,共6页
A 1.60μm laser diode and electroabsorption modulator monolithically integrated with a novel dual-waveguide spot-size converter output for low-loss coupling to a cleaved single-mode optical fiber are demonstrated.The ... A 1.60μm laser diode and electroabsorption modulator monolithically integrated with a novel dual-waveguide spot-size converter output for low-loss coupling to a cleaved single-mode optical fiber are demonstrated.The devices emit in a single transverse and quasi single longitudinal mode with an SMSR of 25.6dB.These devices exhibit a 3dB modulation bandwidth of 15.0GHz,and modulator DC extinction ratios of 16.2dB.The output beam divergence angles of the spot-size converter in the horizontal and vertical directions are as small as 7.3°×18.0°,respectively,resulting in a 3.0dB coupling loss with a cleaved single-mode optical fiber. 展开更多
关键词 laser diode electroabsorption modulator spot-size converter integrated optoelectronics optical coupling
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An Electroabsorption Modulator Monolithically Integrated with a Semiconductor Optical Amplifier and a Dual-Waveguide Spot-Size Converter
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作者 侯廉平 王圩 +3 位作者 朱洪亮 周帆 王鲁峰 边静 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第8期1504-1508,共5页
A semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a spotsize converter input and output is fabricated by means of selective area growth,quantum well intermixing,and asymm... A semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a spotsize converter input and output is fabricated by means of selective area growth,quantum well intermixing,and asymmetric twin waveguide technology. A 1550-1600nm lossless operation with a high DC extinction ratio of 25dB and more than 10GHz 3dB bandwidth are successfully achieved. The output beam divergence angles of the device in the horizontal and vertical directions are as small as 7.3°× 18.0°, respectively, resulting in a 3.0dB coupling loss with a cleaved single-mode optical fiber. 展开更多
关键词 semiconductor optical amplifier electroabsorption modulator spot-size converters selective area growth quantum well intermixing asymmetric twin waveguide
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双向隔离型AC-DC矩阵变换器最小开关损耗控制方法
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作者 梅杨 石仪 张家奇 《电工技术学报》 北大核心 2026年第4期1414-1424,共11页
为了实现双向隔离型AC-DC矩阵变换器(BIMC)的高效运行,该文提出一种最小开关损耗控制方法。基于双线电压调制策略,建立电力电子器件损耗模型,引入基于序列二次规划算法(SQP)的优化方法,以输入功率和移相角范围为限定条件,对开关损耗进... 为了实现双向隔离型AC-DC矩阵变换器(BIMC)的高效运行,该文提出一种最小开关损耗控制方法。基于双线电压调制策略,建立电力电子器件损耗模型,引入基于序列二次规划算法(SQP)的优化方法,以输入功率和移相角范围为限定条件,对开关损耗进行最小化寻优,实时计算最优的移相角组合,并应用于变换器的调制过程,以保证变换器的开关损耗最小。仿真和实验结果表明,采用所提出的控制方法可实现网侧电流为正弦电流,功率因数接近于1,直流侧电压与电流稳定,电流纹波率小于1%,且在较宽功率范围内,变换器效率均维持在94%以上,最高可达到96.89%。相较于传统的控制方法而言,所提方法在宽运行范围中均可以使电力电子器件的损耗最小。 展开更多
关键词 AC-dC矩阵变换器 双线电压调制策略 开关损耗 序列二次规划
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Resiliency oriented control of a smart microgrid with photovoltaic modules 被引量:2
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作者 Sambeet Mishra Kristjan Peterson +3 位作者 Tauno Hilimon Jelena Shuvalova Fushuan Wen Ivo Palu 《Global Energy Interconnection》 EI CAS CSCD 2021年第5期441-452,共12页
The resiliency of a standalone microgrid is of considerable issue because the available regulation measures and capabilities are limited.Given this background,this paper presented a new mathematical model for a detail... The resiliency of a standalone microgrid is of considerable issue because the available regulation measures and capabilities are limited.Given this background,this paper presented a new mathematical model for a detailed photovoltaic(PV)module and the application of new control techniques for efficient energy extraction.The PV module employs a single-stage conversion method to integrate it with the utility grid.For extraction the maximum power from PV and integrate it to power grid,a three-phase voltage source converter is used.For obtaining the maximum power at a particular irradiance a maximum power point tracking(MPPT)scheme is used.The fuzzy logic control and adaptive network-based fuzzy inference system are proposed for direct current(DC)link voltage control.The proposed model and control scheme are validated through a comparison with the standard power-voltage and current-voltage charts for a PV module.Simulation results demonstrate that the system stability can be maintained with the power grid and in the island mode,in contrast with the MPPT. 展开更多
关键词 PV module MPPT Adaptive network-based fuzzy inference system(ANFIS) converter control Grid integration
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Research on the Topology and Control Scheme of an Innovative Modular Multilevel Converter 被引量:1
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作者 Daixiang Zhu Ming Ding 《Energy and Power Engineering》 2013年第4期1512-1516,共5页
This paper presents a new modular multilevel converter (MMC) topology. Compared to conventional multilevel converters, MMC has much lower switching frequency (50 Hz) resulting in lower switching losses, and consequent... This paper presents a new modular multilevel converter (MMC) topology. Compared to conventional multilevel converters, MMC has much lower switching frequency (50 Hz) resulting in lower switching losses, and consequently, lower total losses of the transmission system. The fundamental concept and the applied control scheme are introduced in detail. A modified multilevel fundamental switching modulation scheme adopting the multicarrier pulse width modulation concept is presented. A capacitor voltage balancing technique is proposed. With the established simulation model of the 11-level MMC, the modulation and balancing strategy presented are confirmed by MATLAB/SIMULINK simulations. The multicarrier pulse width modulation converter strategy enhances the fundamental output voltage and reduces total harmonic distortion. This new type of converter is suitable for high-voltage drive systems and power system applications such as high voltage dc (HVDC) transmission, reactive power compensation equipment and so on. 展开更多
关键词 Sub-modular modulAR MULTILEVEL converter FUNdAMENTAL Switching modulation TOPOLOGY CAPACITOR Voltage Balancing
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Distributed High Efficiency Renewable Power Systems With Modules in Series Connection 被引量:1
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作者 WU Hongfei SUN Kai XING Yan 《中国电机工程学报》 EI CSCD 北大核心 2012年第33期I0001-I0022,共22页
Renewable power modules such as the thermoelectric generator and the PV panel are featured by low output voltage and low power.Aiming at maximum output power,a high energy efficiency module integrated converter(MIC),a... Renewable power modules such as the thermoelectric generator and the PV panel are featured by low output voltage and low power.Aiming at maximum output power,a high energy efficiency module integrated converter(MIC),as shown in Fig.1,and its control strategy for series connected distributed(SCD)renewable power systems,as shown in Fig.2,are proposed.The topology of the MIC is an improved one of the conventional H-bridge Buck-Boost converter. 展开更多
关键词 distributed power system module integrated converter renewable power system Buck-Boost converter high energy efficiency
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A Review of Modular Multilevel Converters 被引量:99
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作者 YANG Xiaofeng LIN Zhiqin ZHENG Trillion Q. YOU Xiaojie 《中国电机工程学报》 EI CSCD 北大核心 2013年第6期I0001-I0022,共22页
模块组合多电平变换器(modular multilevel converter,MMC)具有高度模块化、易于扩展、输出电压波形好等特点,尤其适用于中高压大功率系统应用。首先介绍MMC的电路拓扑和工作原理,总结MMC的主要技术特点;然后分别回顾MMC在脉冲调... 模块组合多电平变换器(modular multilevel converter,MMC)具有高度模块化、易于扩展、输出电压波形好等特点,尤其适用于中高压大功率系统应用。首先介绍MMC的电路拓扑和工作原理,总结MMC的主要技术特点;然后分别回顾MMC在脉冲调制、直流电压控制、预充电、环流、谐波、数学模型、主电路参数设计、故障保护等关键问题的最新研究进展,以及其在电力传动、电能质量问题治理领域的工程应用现状,在此基础上指出MMC今后亟待研究的关键问题。相关研究结果表明,MMC在电力系统中有广泛的应用前景,是未来中高压大功率系统,尤其是高压输电技术的重要发展方向。 展开更多
关键词 多电平变换器 模块化 直流电容器 工作电压 电平转换器 拓扑结构 电路布局 工业应用
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Recent Developments of Modulation and Control for High-Power Current-Source-Converters Fed Electric Machine Systems 被引量:5
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作者 Pengcheng Liu Zheng Wang +2 位作者 Sanmin Wei Yuwen Bo Shaoning Pu 《CES Transactions on Electrical Machines and Systems》 CSCD 2020年第3期215-226,共12页
The pulse-width-modulated(PWM)current-source converters(CSCs)fed electric machine systems can be considered as a type of high reliability energy conversion systems,since they work with the long-life DC-link inductor a... The pulse-width-modulated(PWM)current-source converters(CSCs)fed electric machine systems can be considered as a type of high reliability energy conversion systems,since they work with the long-life DC-link inductor and offer high fault-tolerant capability for short-circuit faults.Besides,they provide motor friendly waveforms and four-quadrant operation ability.Therefore,they are suitable for high-power applications of fans,pumps,compressors and wind power generation.The purpose of this paper is to comprehensively review recent developments of key technologies on modulation and control of high-power(HP)PWM-CSC fed electric machines systems,including reduction of low-order current harmonics,suppression of inductor–capacitor(LC)resonance,mitigation of common-mode voltage(CMV)and control of modular PWM-CSC fed systems.In particular,recent work on the overlapping effects during commutation,LC resonance suppression under fault-tolerant operation and collaboration of modular PMW-CSCs are described.Both theoretical analysis and some results in simulations and experiments are presented.Finally,a brief discussion regarding the future trend of the HP CSC fed electric machines systems is presented. 展开更多
关键词 Current source converter(CSC) high power(HP)applications electric machine system inductor–capacitor(LC)resonance low-order current harmonics common-mode voltage(CMV) modulATION control
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A Novel Square-wave Pulse Rotation Modulation Strategy for Modular Multilevel Converters 被引量:9
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作者 YANG Xiaofeng LIN Zhiqin ZHENG Trillion Q YOU Xiaojie 《中国电机工程学报》 EI CSCD 北大核心 2013年第9期I0006-I0006,共1页
悬浮直流电容电压的均衡问题是模块组合多电平变换器(modular multilevel converter,MMC)的关键问题之一。提出一种可实现MMC直流电容电压平衡的方波脉冲循环调制(square-wave pulse rotation modulation,SWPRM)策略,在保证合成的... 悬浮直流电容电压的均衡问题是模块组合多电平变换器(modular multilevel converter,MMC)的关键问题之一。提出一种可实现MMC直流电容电压平衡的方波脉冲循环调制(square-wave pulse rotation modulation,SWPRM)策略,在保证合成的阶梯波输出波形不变的前提下,根据MMC的拓扑结构和工作原理,对传统方波脉冲列进行脉冲优化,并按照一定的次序和切换周期进行循环和判断反相调整,获得的循环方波脉冲列作为最终驱动脉冲用于实现对MMC的控制。实验结果表明,采用提出的方波脉冲循环调制策略无需任何电容电压控制措施,在较低开关频率下,实现了MMC各功率单元间有功能量的平均分配和直流电容电压的均衡。 展开更多
关键词 调制策略 方波脉冲 多电平变流器 模块化 旋转 直流电容器 多电平变换器 平衡控制
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DC-Modulated PFC Buck-Type AC/AC Converter for Light Dimming 被引量:3
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作者 罗方林 叶虹 《电工电能新技术》 CSCD 北大核心 2007年第2期6-10,38,共6页
Dimmers are very widely applied in theatres,cinemas,dancing-parties, auditoriums and signal systems.They are usually supplied by single-stage AC/AC converters in the past with voltage regulation technique with the dis... Dimmers are very widely applied in theatres,cinemas,dancing-parties, auditoriums and signal systems.They are usually supplied by single-stage AC/AC converters in the past with voltage regulation technique with the disadvantages of high total harmonic distortion,low power factor and poor power transfer efficiency.This paper introduces a novel method-DC-modulation that implements DC/DC conversion technology into AC/AC converters.The DC-modulated single-stage PFC AC/AC converters effectively improved the power factor up to 0.999 and the power transfer efficiency up to 97.8 %.The experimental results verified our design and calculation.This technique will be widely used in light dimming and other industrial applications. 展开更多
关键词 直流电 交流电 节电措施 灯光亮度
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A Study on the Modeling and Design of Sigma-Delta Modulator for High Precision ADC
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作者 Haodong Guo Longyu Li Xia Zhang 《Journal of Electronic Research and Application》 2025年第2期240-246,共7页
With the continuous improvement of signal processing accuracy requirements in modern electronic systems,the demand for high-precision analog-to-digital converters(ADCs)is increasing.Sigma-Delta modulator,as the most i... With the continuous improvement of signal processing accuracy requirements in modern electronic systems,the demand for high-precision analog-to-digital converters(ADCs)is increasing.Sigma-Delta modulator,as the most important component of high-precision ADC,is widely used in high-quality audio,high-precision instrument measurement,and other fields due to its advantages of high precision,strong noise resistance,and low hardware cost.This article designs a discrete structure third-order four-bit high-precision Sigma-Delta modulator through modeling,with an oversampling rate set to 512.Under ideal conditions,the simulation results show that the SDNR reaches 152.7db and the ENOB is 25.24bits.After introducing non-ideal noise,the system performance has decreased.The simulation results show that the SDNR is as high as 124.5db and the ENOB is 20.39bits.This indicates that the design can achieve high-precision conversion and provide assistance for further research in the future. 展开更多
关键词 Analog-to-digital converter Sigma-delta modulator High precision Modeling design
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A “Tonebusting” Technique to Build a DAC from a First-Order Digital ΣΔ Modulator
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作者 Yves Leduc Gilles Jacquemod +1 位作者 Yoann Charlon Fabrice Muller 《Journal of Electronic Research and Application》 2025年第4期8-13,共6页
In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial le... In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial level of dithering noise into the input signal,strategically aimed at mitigating the spurious frequencies commonly encountered in such converters.Validation of our design is performed through simulations using a high-level simulator specialized in mixed-signal circuit analysis.The results underscore the enhanced performance of our circuit,especially in reducing spurious frequencies,highlighting its efficiency and effectiveness.The final circuit exhibits an effective number of bits of 13. 展开更多
关键词 First-order digital Sd modulator digital to analog converter Spurious frequencies dithering
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Adhesion of 2D Materials: Measurement and Modulation
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作者 Na Li Hongrong Wu +1 位作者 Changwei Sun Junhua Zhao 《Acta Mechanica Solida Sinica》 2025年第2期252-274,共23页
Two-dimensional(2D)materials are promising for next-generation electronic devices and systems due to their unique physical properties.The interfacial adhesion plays a vital role not only in the synthesis,transfer and ... Two-dimensional(2D)materials are promising for next-generation electronic devices and systems due to their unique physical properties.The interfacial adhesion plays a vital role not only in the synthesis,transfer and manipulation of 2D materials but also in the manufacture,integration and performance of the functional devices.However,the atomic thickness and limited lateral dimensions of 2D materials make the accurate measurement and modulation of their interfacial adhesion energy challenging.In this review,the recent advances in the measurement and modulation of the interfacial adhesion properties of 2D materials are systematically combed.Experimental methods and relative theoretical models for the adhesion measurement of 2D materials are summarized,with their scope of application and limitations discussed.The measured adhesion energies between 2D materials and various substrates are described in categories,where the typical adhesion modulation strategies of 2D materials are also introduced.Finally,the remaining challenges and opportunities for the interfacial adhesion measurement and modulation of 2D materials are presented.This paper provides guidance for addressing the adhesion issues in devices and systems involving 2D materials. 展开更多
关键词 2d materials AdHESION MEASUREMENT modulATION
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基于Production Module 3D数控铣削仿真技术在钛合金主吊挂加工中的应用 被引量:3
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作者 吴东华 邓志刚 +2 位作者 张德纯 赵万岳 丁代华 《机械工程师》 2021年第11期149-152,155,共5页
在钛合金主吊挂支架的铣削过程中,采用Production Module 3D软件对数控程序、材料、刀具及工件的综合分析,得到了在整个数控程序下的温度峰值、进给力、切削力及材料去除率等数据。然后采用完善数控程序中的吃刀量、切削速度及进给量来... 在钛合金主吊挂支架的铣削过程中,采用Production Module 3D软件对数控程序、材料、刀具及工件的综合分析,得到了在整个数控程序下的温度峰值、进给力、切削力及材料去除率等数据。然后采用完善数控程序中的吃刀量、切削速度及进给量来使加工过程中温度、切削力等符合要求,使负载平衡,降低振动。最终刀具的使用寿命提高20%,加工周期降低22%。 展开更多
关键词 钛合金 铣削 Production module 3d
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一种基于共源共栅浮空反相放大器的低功耗高精度Sigma-Delta调制器
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作者 杨吉城 卢宏斌 +4 位作者 牛瑞玲 李耀东 刘照 汪家奇 常玉春 《中国集成电路》 2026年第1期43-49,共7页
提出了一种具有新型偏置电路的共源共栅浮空反相放大器(FIA)。该共源共栅FIA具有和共模电平偏置的共源共栅FIA相同量级的增益,而无需使用低阈值电压管或大面积共栅管,提高了适用性和面积效率。使用该FIA设计了一种低功耗高精度Sigma-De... 提出了一种具有新型偏置电路的共源共栅浮空反相放大器(FIA)。该共源共栅FIA具有和共模电平偏置的共源共栅FIA相同量级的增益,而无需使用低阈值电压管或大面积共栅管,提高了适用性和面积效率。使用该FIA设计了一种低功耗高精度Sigma-Delta调制器。调制器基于SMIC 180 nm工艺设计,采用三阶CIFF-B单环结构。通过1.5 bit量化、FIR DAC反馈以及调整积分器增益系数,降低了各级积分器的输出范围,从而与FIA的输出范围相匹配,降低了整体功耗。前仿真结果显示,该调制器在1.8V电源电压和1 MHz采样时钟下,在1 kHz的信号带宽内具有108 dB的峰值信噪失真比(SNDR),功耗仅为23.9μW,实现了高达184.2 dB的基于SNDR的优值(FoM)。 展开更多
关键词 SIGMA-dELTA调制器 模数转换器 浮空反相放大器 低功耗
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Scutellaria barbata D.Don extracts alleviate SARS-CoV-2 induced acute lung injury by inhibiting virus replication and bi-directional immune modulation
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作者 Yan Ran Zinuo Chen +4 位作者 Carolina Q.Sacramento Lingyuan Fan Qinghua Cui Lijun Rong Ruikun Du 《Virologica Sinica》 2025年第3期430-438,共9页
The emergence of SARS-CoV-2 variants and drug-resistant mutants emphasizes the urgent need to develop novel antiviral agents.In the present study,we examined the therapeutic effect of the Chinese medicinal herb,Scutel... The emergence of SARS-CoV-2 variants and drug-resistant mutants emphasizes the urgent need to develop novel antiviral agents.In the present study,we examined the therapeutic effect of the Chinese medicinal herb,Scutellaria barbata D.Don(SBD),against SARS-CoV-2 infection both in vitro and in vivo.Using a viral replicon particle(VRP)-based mouse model of SARS-CoV-2 infection,our study revealed that SBD extracts can reduce viral load in mouse lungs and alleviate the viral induced pneumonia.In vitro antiviral determination further validated the direct acting antiviral efficacy of SBD extracts against SARS-CoV-2 replication.Mechanistic studies demonstrated that SBD can act against SARS-CoV2 replication by targeting both 3-chymotrypsin-like and papain-like cysteine proteases,via a combination of multiple active constituents.Moreover,SBD can modulate the host inflammation response in a bi-directional manner,which also contribute to the mitigation of viral induced acute lung injury.In summary,our study provides SBD as a promising therapeutic agent to combat SARS-CoV-2 infections that merit further development. 展开更多
关键词 SARS-CoV-2 Scutellaria barbata d.don ANTIVIRAL Bi-directional immune modulation
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Modulatory role of vitamin D in atopic dermatitis and allergic rhinitis
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作者 Chandra Sekhar Devulapalli 《World Journal of Clinical Pediatrics》 2025年第4期189-195,共7页
Vitamin D,beyond its classical role in calcium homeostasis,has emerged as a key regulator of immune function and epithelial barrier integrity.Its deficiency during early childhood—a critical period for immune maturat... Vitamin D,beyond its classical role in calcium homeostasis,has emerged as a key regulator of immune function and epithelial barrier integrity.Its deficiency during early childhood—a critical period for immune maturation—has been increasingly implicated in the development of atopic diseases.While extensively studied in asthma,its role in non-respiratory allergic conditions such as atopic dermatitis(AD)and allergic rhinitis(AR)remains comparatively underexplored.This minireview synthesizes current mechanistic and clinical evidence on vitamin D in pediatric AD and AR.In AD,vitamin D promotes epidermal barrier function through upregulation of filaggrin and ceramide synthesis,and enhances antimicrobial defense via induction of antimicrobial peptides.Observational studies consistently report lower serum 25-hydroxyvitamin D in affected children,particularly those with allergic sensitization.Select randomized controlled trials suggest clinical improvement with supplementation,especially at doses>2000 IU/day in deficient individuals.In AR,epidemiological data indicate stronger inverse associations with seasonal(pollen-induced)disease.Proposed mechanisms include modulation of dendritic cells,regulatory T cells,T helper 2 cytokines,and mucosal barrier integrity.The shared immunopathogenesis of AD and AR underscores vitamin D’s relevance.Although promising,clinical evidence remains heterogeneous.Future research should prioritize phenotype-stratified trials to clarify optimal dosing,timing,and individual response determinants,including genetics and microbiome composition. 展开更多
关键词 Vitamin d Atopic dermatitis Allergic rhinitis Pediatric allergy Immune modulation Epithelial barrier function Vitamin d receptor Allergic sensitization Earlylife immunity Genetic polymorphism
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