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玉米蛋白源DPP-IV抑制肽的酶法制备及其性质研究
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作者 陶莉 王俊彤 +3 位作者 李冠龙 姜彩霞 郑喜群 刘晓兰 《食品工业科技》 北大核心 2026年第1期289-299,共11页
本文以玉米蛋白粉为原料制备对二肽基肽酶(Dipeptidyl peptidase-IV,DPP-IV)具有抑制作用的生物活性肽。采用酶法制备技术筛选出对DPP-IV抑制效果最佳的蛋白酶,通过单因素及响应面优化试验确定最佳酶解条件,并进一步对制得的抑制肽进行... 本文以玉米蛋白粉为原料制备对二肽基肽酶(Dipeptidyl peptidase-IV,DPP-IV)具有抑制作用的生物活性肽。采用酶法制备技术筛选出对DPP-IV抑制效果最佳的蛋白酶,通过单因素及响应面优化试验确定最佳酶解条件,并进一步对制得的抑制肽进行分子量分布、超滤分级及氨基酸组成等分析。结果表明:中性蛋白酶制备玉米蛋白源DPP-IV抑制肽的效果最佳,工艺优化得到的最佳酶解条件为底物浓度10%(w/v)、酶添加量640 U/g、酶解时间157 min、酶解温度45℃、酶解pH7.0。该条件下得到的抑制肽对DPP-IV的半抑制浓度(Half-inhibitory concentration,IC_(50))值为0.53±0.06 mg/mL。超滤分级后小于1 kDa组分分子量占原抑制肽的58.9%,对DPP-IV的抑制活性高于原抑制肽,这与其氨基酸组成有关。酶促反应动力学分析结果表明制备的抑制肽对DPP-IV的抑制类型属于竞争性可逆抑制。本研究结果为玉米蛋白源DPP-IV抑制肽的开发利用提供了理论依据,为玉米蛋白的高值化利用提供新思路。 展开更多
关键词 玉米蛋白源抑制肽 中性蛋白酶 二肽基肽酶-IV(dpp-IV) 2 型糖尿病(T2DM)
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Thermally Drawn Flexible Fiber Sensors:Principles,Materials,Structures,and Applications
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作者 ZhaoLun Zhang Yuchang Xue +7 位作者 Pengyu Zhang Xiao Yang Xishun Wang Chunyang Wang Haisheng Chen Xinghua Zheng Xin Yin Ting Zhang 《Nano-Micro Letters》 2026年第1期95-129,共35页
Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexib... Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed. 展开更多
关键词 Thermally drawn fiber sensors Sensing principles Temperature sensors Mechanical sensors Multifunctional sensors
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DPP-4抑制剂联合用药在治疗糖尿病及并发症中的应用
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作者 董琳 徐雅莉 李清 《华西药学杂志》 北大核心 2025年第5期595-599,共5页
二肽基肽酶-Ⅳ(DPP-4)抑制剂作为治疗2型糖尿病的二线药物,具有良好的血糖控制能力和较少的不良反应。现基于DPP-4抑制剂的研究现状,综述其联合用药方案在1型、2型糖尿病及其并发症中的应用,以期为临床应用提供依据。
关键词 二肽基肽酶-Ⅳ抑制剂 联合用药 1型糖尿病 2型糖尿病及其并发症治疗 二甲双胍
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LncRNA CTBP1-AS2调节miR-433-3p/DPP8信号轴对急性髓系白血病细胞恶性生物学行为的影响
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作者 刘苏慧 段丽娟 +2 位作者 李超 秦凡 尚淼 《中国免疫学杂志》 北大核心 2025年第11期2631-2636,共6页
目的:探讨LncRNA C-末端结合蛋白-1反义RNA2(CTBP1-AS2)调节miR-433-3p/二肽基肽酶8(DPP8)信号轴对急性髓系白血病(AML)细胞恶性生物学行为的影响。方法:AML细胞HL-60随机分为si-NC组、si-CTBP1-AS2组、si-CTBP1-AS2+anti-NC组、si-CTBP... 目的:探讨LncRNA C-末端结合蛋白-1反义RNA2(CTBP1-AS2)调节miR-433-3p/二肽基肽酶8(DPP8)信号轴对急性髓系白血病(AML)细胞恶性生物学行为的影响。方法:AML细胞HL-60随机分为si-NC组、si-CTBP1-AS2组、si-CTBP1-AS2+anti-NC组、si-CTBP1-AS2+anti-miR-433-3p组。CCK-8法和EdU染色检测HL-60细胞增殖;流式细胞术检测HL-60细胞凋亡;Transwell检测HL-60细胞迁移和侵袭;Western blot检测HL-60细胞PCNA、Bax、MMP-9、DPP8蛋白表达;ELISA检测HL-60细胞IFN-γ、IL-1β表达;双荧光素酶报告基因实验分析LncRNA CTBP1-AS2与miR-433-3p、miR-433-3p与DPP8的相互作用。结果:si-CTBP1-AS2组HL-60细胞LncRNA CTBP1-AS2、DPP8 mRNA、A_(450)、EdU阳性细胞率、迁移细胞数、侵袭细胞数、PCNA蛋白、MMP-9蛋白、DPP8蛋白、IL-1β蛋白表达低于si-NC组,miR-433-3p表达、凋亡率、Bax蛋白、IFN-γ蛋白表达高于si-NC组(P<0.05);与si-CTBP1-AS2组、si-CTBP1-AS2+anti-NC组比较,si-CTBP1-AS2+anti-miR-433-3p组miR-433-3p、凋亡率、Bax蛋白、IFN-γ蛋白表达降低,DPP8 mRNA、A_(450)、EdU阳性细胞率、迁移细胞数、侵袭细胞数、PCNA蛋白、MMP-9蛋白、DPP8蛋白、IL-1β蛋白表达升高(P<0.05)。LncRNA CTBP1-AS2靶向负调控miR-433-3p,miR-433-3p靶向负调控DPP8。结论:敲低LncRNA CTBP1-AS2可能抑制AML细胞恶性生物学行为,其机制可能通过调节miR-433-3p/DPP8信号轴实现。 展开更多
关键词 LncRNA CTBP1-AS2 miR-433-3p dpp8 急性髓系白血病
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DPP4-Nestin轴在泡球蚴感染所致肝纤维化的促进作用及机制
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作者 高瑾 孙涛 +11 位作者 木克西娜·木拉提 何小龙 石晶 李亮 杨宁 楚瑨 张雪 刘辉 吕国栋 林仁勇 毕晓娟 郭庆勇 《中国兽医学报》 北大核心 2025年第2期298-304,共7页
为探讨DPP4-Nestin轴在泡球蚴感染引起肝纤维化过程中的作用,选取C57BL/6小鼠通过肝门静脉构建泡球蚴感染模型,HE法检测肝脏组织病理学变化,免疫组化、免疫荧光检测Nestin及DPP4在泡球蚴感染小鼠肝脏中的表达;以DPP4重组蛋白刺激小鼠肝... 为探讨DPP4-Nestin轴在泡球蚴感染引起肝纤维化过程中的作用,选取C57BL/6小鼠通过肝门静脉构建泡球蚴感染模型,HE法检测肝脏组织病理学变化,免疫组化、免疫荧光检测Nestin及DPP4在泡球蚴感染小鼠肝脏中的表达;以DPP4重组蛋白刺激小鼠肝星状细胞系JS1构建体外模型,qPCR、Western blot、shRNA慢病毒干扰等方法检测DPP4-Nestin轴在肝星状细胞激活过程中的作用。结果显示:与Sham组相比,泡球蚴感染组肝脏组织结构破坏,胶原沉积明显,Nestin和DPP4表达显著升高(P<0.050 0),且Nesin与α-SMA存在共定位;与对照组相比,DPP4重组蛋白刺激可明显刺激JS1细胞激活(P<0.050 0),并且Nestin表达升高(P<0.050 0),shRNA慢病毒抑制JS1细胞Nestin表达可明显抑制DPP4重组蛋白对JS1细胞的活化作用(P<0.050 0)。综上所述,DPP4-Nestin轴在泡球蚴感染引起肝星状细胞活化过程中具有重要调节作用,靶向DPP4-Nestin轴可作为治疗泡球蚴感染所致肝纤维化的新途径。 展开更多
关键词 泡型棘球蚴 NESTIN dpp4 小鼠
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以DPP4为靶点探讨中药对RA的干预作用
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作者 魏建中 孙继佳 +3 位作者 袁颖 张磊 李成蹊 王健英 《中国民族民间医药》 2025年第17期59-64,76,共7页
二肽基肽酶IV(DPP4)属于丝氨酸蛋白酶家族,可以水解多种蛋白质,执行多种重要的生物学功能。目前已上市的DPP4抑制剂主要用于糖尿病,但长期使用会产生严重的类风湿关节炎症状。越来越多的研究信息表明DPP4与RA具有联系。中药具有多成分... 二肽基肽酶IV(DPP4)属于丝氨酸蛋白酶家族,可以水解多种蛋白质,执行多种重要的生物学功能。目前已上市的DPP4抑制剂主要用于糖尿病,但长期使用会产生严重的类风湿关节炎症状。越来越多的研究信息表明DPP4与RA具有联系。中药具有多成分、多途径、多靶点效用,在调节血糖和干预RA方面具有作用。文章归纳DPP4对RA的影响,以及中药对RA的干预作用,探讨中药是否可以通过调控DPP4,从而干预RA的发生发展,可为研究中药对DPP4的作用,开发能改善DPP4抑制剂副作用或作用于DPP4靶点干预RA的中药新药提供研究思路。 展开更多
关键词 二肽基肽酶IV(dpp4) 类风湿关节炎(RA) 中药 免疫
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First-principles study on the structure-property relationship of AlX and InX(X=N,P,As,Sb)
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作者 HE Zhihao DING Jiafu +1 位作者 WANG Yunjie SU Xin 《无机化学学报》 北大核心 2025年第5期1007-1019,共13页
This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materi... This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications. 展开更多
关键词 aluminium‑based semiconductor indium‑based semiconductor first principle electronic structure optical property
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UNCERTAINTY PRINCIPLES AND SIGNAL RECOVERY RELATED TO THE CANONICAL FOURIER-BESSEL TRANSFORM
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作者 Jihed SAHBANI Lazhar DHAOUADI 《Acta Mathematica Scientia》 2025年第5期2190-2207,共18页
The aim of this paper is to prove another variation on the Heisenberg uncertainty principle,we generalize the quantitative uncertainty relations in n different(time-frequency)domains and we will give an algorithm for ... The aim of this paper is to prove another variation on the Heisenberg uncertainty principle,we generalize the quantitative uncertainty relations in n different(time-frequency)domains and we will give an algorithm for the signal recovery related to the canonical Fourier-Bessel transform. 展开更多
关键词 Fourier Bessel transform linear canonical transform quantitative uncertainty principles Heisenberg uncertainty principle signal recovery
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AGU Posts Principles to Guide-and Foster-Geoengineering Research
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作者 Sean Cummings 《Engineering》 2025年第9期10-13,共4页
On 17 October 2024,the American Geophysical Union(AGU)in Washington,DC,USA,released the Ethical Framework Principles for Climate Intervention Research[1],a set of guidelines designed to help scientists,funders,policym... On 17 October 2024,the American Geophysical Union(AGU)in Washington,DC,USA,released the Ethical Framework Principles for Climate Intervention Research[1],a set of guidelines designed to help scientists,funders,policymakers,and private entities research and govern geoengineering technologies as ethically as possible.Commissioned in 2022 by the AGU Board of Directors and produced with internal funding only,the document advocates that geoengineering research projects fully consider all possible risks and benefits-environmental,sociocultural,and geopolitical-and include input from any groups such projects might impact. 展开更多
关键词 ethical framework environmental risks GEOENGINEERING geopolitical considerations research principles climate intervention sociocultural impacts ethical framework principles
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The Concretization of the Principle of Equality:A Hermeneutic Reconstruction of Article 33,Paragraph 4 of the Chinese Constitution
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作者 LIU Jianlong JIANG Yu(Translated) 《The Journal of Human Rights》 2025年第1期149-163,共15页
Traditional constitutional theory holds that Article 33,Paragraph 4 of the Chinese Constitution establishes the principle of the consistency of rights and obligations.However,with the evolution of constitutional theor... Traditional constitutional theory holds that Article 33,Paragraph 4 of the Chinese Constitution establishes the principle of the consistency of rights and obligations.However,with the evolution of constitutional theory and practice,its interpretation has shifted.It is increasingly viewed as a concretization of the principle of equality,although this perspective has not been thoroughly substantiated in academic circles.Upon closer analysis,interpreting this provision as the“consistency of rights and obligations”reveals several issues,including counterevidence from the constitutional drafting history,a lack of internal coherence,and a misalignment with the functions of the Constitution.By revisiting the specific context of this provision,it can be understood as an anti-privilege clause,serving as a special annotation of the equality principle.This approach enables a harmonious interpretation of this provision alongside other constitutional provisions. 展开更多
关键词 principle of the consistency of rights and obligations principle of equality anti-privilege
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RENEWING A TIMELESS BOND Commemorating 75 years of China-Myanmar ties and revitalizing the legacy of the Five Principles of Peaceful Coexistence
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作者 Hou Sheng 《China Report ASEAN》 2025年第6期60-63,共4页
Over 70 years ago,China proposed the Five Principles of Peaceful Coexistence,which were first embraced by countries such as Myanmar and gradually gained traction across Asia.The Five Principles eventually became widel... Over 70 years ago,China proposed the Five Principles of Peaceful Coexistence,which were first embraced by countries such as Myanmar and gradually gained traction across Asia.The Five Principles eventually became widely recognized norms in international relations and foundational principles of international law,contributing significantly to the post-World War II international order.Decades on,the Five Principles have not faded into history.Rather,they have demonstrated renewed relevance in today’s complex global landscape. 展开更多
关键词 Post World War II Order International Relations Five principles Peaceful Coexistence China five principles peaceful coexistencewhich Global Landscape International Law Myanmar
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DPP4蛋白检测在中医治疗风湿免疫病中的潜在作用研究
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作者 魏建中 王健英 《内蒙古中医药》 2025年第6期143-144,共2页
二肽基肽酶IV(DPP4)属于丝氨酸蛋白酶家族,DPP4能够对DPP4酶进行抑制,促进循环中的肠促胰岛素激素、胰高血糖素样肽-1、葡萄糖依赖性促胰岛素多肽的完整生物活性水平均得到提升。风湿免疫病与患者自身的免疫系统存在紧密的联系,极易加... 二肽基肽酶IV(DPP4)属于丝氨酸蛋白酶家族,DPP4能够对DPP4酶进行抑制,促进循环中的肠促胰岛素激素、胰高血糖素样肽-1、葡萄糖依赖性促胰岛素多肽的完整生物活性水平均得到提升。风湿免疫病与患者自身的免疫系统存在紧密的联系,极易加重关节多个器官系统的损伤。近年风湿免疫病逐渐运用中医治疗方案,能够发挥多靶点作用,因此本文主要对DPP4蛋白检测在中医治疗风湿免疫病中的潜在作用进行综述,以期为临床通过DPP4靶点治疗风湿免疫病的中药新药提供新的研究思路。 展开更多
关键词 二肽基肽酶IV(dpp4) 风湿免疫病 中医治疗 免疫
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Generalized uncertainty principle from the regularized self-energy
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作者 Kimet Jusufi Ahmed Farag Ali 《Communications in Theoretical Physics》 2025年第1期92-100,共9页
We use the Schrödinger–Newton equation to calculate the regularized self-energy of a particle using a regular self-gravitational and electrostatic potential derived in string T-duality.The particle mass M is no ... We use the Schrödinger–Newton equation to calculate the regularized self-energy of a particle using a regular self-gravitational and electrostatic potential derived in string T-duality.The particle mass M is no longer concentrated into a point but is diluted and described by a quantum-corrected smeared energy density resulting in corrections to the energy of the particle,which is interpreted as a regularized self-energy.We extend our results and find corrections to the relativistic particles using the Klein–Gordon,Proca and Dirac equations.An important finding is that we extract a form of the generalized uncertainty principle(GUP)from the corrected energy.This form of the GUP is shown to depend on the nature of particles;namely,for bosons(spin 0 and spin 1)we obtain a quadratic form of the GUP,while for fermions(spin 1/2)we obtain a linear form.The correlation we find between spin and GUP may offer insights for investigating quantum gravity. 展开更多
关键词 generalized uncertainty principle T-DUALITY regularized self-energy
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Predicted stable two-dimensional semiconductor TiOS materials with promising photocatalytic properties:First-principles calculations
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作者 Pan Zhang Shihai Fu +2 位作者 Chunying Pu Xin Tang Dawei Zhou 《Chinese Physics B》 2025年第5期534-541,共8页
TiO_(2)is a well-known photocatalyst with a band gap of 3.2 eV,yet its ability to absorb light is limited to the short wavelengths of ultraviolet light.To achieve a more effective photocatalytic material,we have desig... TiO_(2)is a well-known photocatalyst with a band gap of 3.2 eV,yet its ability to absorb light is limited to the short wavelengths of ultraviolet light.To achieve a more effective photocatalytic material,we have designed two-dimensional semiconductor TiOS materials using swarm intelligence algorithms combined with first-principles calculations.Three stable low-energy structures with space groups of P2_(1)/m,P3m1 and P2_(1)/c are identified.Among these structures,the Janus P3m1 phase is a direct bandgap semiconductor,while the P2_(1)/m and P2_(1)/c phases are indirect bandgap semiconductors.Utilizing the accurate hybrid density functional HSE06 method,the band gaps of the three structures are calculated to be 2.34 eV(P2_(1)/m),2.24 eV(P3m1)and 3.22 eV(P2_(1)/c).Optical calculations reveal that TiOS materials exhibit a good light-harvesting capability in both visible and ultraviolet spectral ranges.Moreover,the photocatalytic calculations also indicate that both P2_(1)/m and P3m1 TiOS can provide a strong driving force for converting H_(2)O to H_(2)and O_(2)in an acidic environment with pH=0.The structural stabilities,mechanical properties,electronic structures and hydrogen evolution reaction activities are also discussed in detail.Our research suggests that two-dimensional TiOS materials have potential applications in both semiconductor devices and photocatalysis. 展开更多
关键词 first principles structure prediction TiOS semiconductor PHOTOCATALYSIS
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Structural and Electronic Properties of the Predicted Two-dimensional AsP_(2)X_(6)(X=S,Se):First-principles Calculations
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作者 PU Chunying ZHANG Pan +1 位作者 YIN Furong ZHOU Dawei 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1612-1619,共8页
The structural,relative stability,and electronic properties of two-dimensional AsP_(2)X_(6)(X=S,Se)were predicted and studied using the particle-swarm optimization method and first principles calculations.We proposed ... The structural,relative stability,and electronic properties of two-dimensional AsP_(2)X_(6)(X=S,Se)were predicted and studied using the particle-swarm optimization method and first principles calculations.We proposed two low energy structures with P312 and P-31m phases,both of which the structures are hexagonal in shape and show non-centrosymmetry for the P312 phase and centrosymmetry for the P-31m phase.According to our results,two structural phases are found to be stable thermally and dynamically.The P312 phase of AsP_(2)X_(6)(X=S,Se)are indirect semiconductors with band gaps of 2.44 eV(AsP2S6)and 2.18 eV(AsP2Se6)at the HSE06 level,and their absorption coefficients are predicted to reach the order of 10^(5)cm^(-1)from visible light to ultraviolet region,but the main absorption is manly in the ultraviolet region.The P-31m phase of AsP_(2)X_(6)(X=S,Se)exhibits metal character with the Fermi surface mainly occupied by the p orbital of S/Se.Remarkably,estimated by first principles calculations,the P-31m AsP2S6 is found to be an intrinsic phonon-mediated superconductor with a relatively high critical superconducting temperature of about 13.4 K,and the P-31m AsP2Se6 only has a superconducting temperature of 1.4 K,which suggest that the P-31m AsP2S6 may be a good candidate for a nanoscale superconductor. 展开更多
关键词 first principles structure prediction electronic structure SUPERCONDUCTIVITY
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First-principles Investigation of Heavy Metal Adsorption on C-lignin
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作者 WANG Juan JIA Leiyu +3 位作者 XU Yao ZHANG Zhenzhen DUAN Ziyu ALBINA Jan-Michael 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1790-1794,共5页
We investigated the adsorption mechanisms including physical and chemical adsorption for heavy metals(Cd,Pb,Zn,Co,Cu)on C-lignin using density functional theory(DFT)simulations.Physical adsorption,involving metal atom... We investigated the adsorption mechanisms including physical and chemical adsorption for heavy metals(Cd,Pb,Zn,Co,Cu)on C-lignin using density functional theory(DFT)simulations.Physical adsorption,involving metal atoms near carbon atoms,is found to be endothermic;meanwhile,chemical adsorption,where hydroxyl groups replace metal ions,is exothermic and spontaneous.Pb exhibits the highest physical adsorption potential,while Cu and Co demonstrate the strongest chemical adsorption due to their highly negative adsorption energies.These findings provide valuable insights into the design of eco-friendly nano lignocellulosic composite films for effective heavy metal removal from contaminated water sources.Key words:C-lignin;adsorption;We investigated the adsorption mechanisms including physical and chemical adsorption for heavy metals(Cd,Pb,Zn,Co,Cu)on C-lignin using density functional theory(DFT)simulations.Physical adsorption,involving metal atoms near carbon atoms,is found to be endothermic;meanwhile,chemical adsorption,where hydroxyl groups replace metal ions,is exothermic and spontaneous.Pb exhibits the highest physical adsorption potential,while Cu and Co demonstrate the strongest chemical adsorption due to their highly negative adsorption energies.These findings provide valuable insights into the design of eco-friendly nano lignocellulosic composite films for effective heavy metal removal from contaminated water sources. 展开更多
关键词 C-lignin ADSORPTION heavy metal ions first principles calculations
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Research Progress on Biomimetic Drag Reduction Materials Inspired by Diverse Organisms:from Principle to Application
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作者 Lei Tang Hongyi Hu +1 位作者 Zhixiang Zeng Qunji Xue 《Journal of Bionic Engineering》 2025年第5期2151-2193,共43页
Reducing the resistance of vehicles,ships,aircraft and other means of transport during movement can significantly improve the speed,save energy and reduce emissions.After billions of years of continuous evolution,orga... Reducing the resistance of vehicles,ships,aircraft and other means of transport during movement can significantly improve the speed,save energy and reduce emissions.After billions of years of continuous evolution,organisms in nature have gradually developed the ability to move at high speed to achieve better survival.These evolved organisms provide a perfect template for the human development of drag reduction materials.Revealing the unique physiological structural characteristics of organisms and their relationship with resistance during movement can provide a feasible approach tosolving the problem of reducing friction resistance.Whether flying in the sky,running on the ground,swimming in the water,or even living in the soil,many creatures in various environments have the ability to reduce resistance.Driven by these inspirations,researchers have done a lot of work to explore and imitate these biological epidermis structures to achieve drag reduction.In this paper,the biomimetic drag reduction materials is introduced in detail in the order of drag reduction mechanism,structural characteristics of biological epidermis(including marine animals,flying animals,soil animals and plants),biomimetic preparation methods,performance testing methods and application fields.Finally,the potential of various biomimetic drag reduction materials in engineering application and the problems to be overcome are summarized and prospected.This paper can help readers comprehensively understand the research progress of biomimetic drag reduction materials,and provide reference for further designing the next generation of drag reduction materials. 展开更多
关键词 Biomimetic drag reduction material principle INSPIRATION Fabrication EXAMINATION APPLICATION
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The Principles of English Teaching in China’s High Schools
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作者 Shufang Qu Tong Wooi Chow 《Journal of Contemporary Educational Research》 2025年第11期172-182,共11页
This article provides a review and summary of the principles of English teaching to achieve breakthroughs in teaching principles.The review of theories such as input-output theory,self-efficacy,and learned helplessnes... This article provides a review and summary of the principles of English teaching to achieve breakthroughs in teaching principles.The review of theories such as input-output theory,self-efficacy,and learned helplessness is not new,but it is useful.These principles are essential theories for guiding educational work,and we must learn them if we want to improve the quality of education.The quality of education in China will improve under the guidance of these theories and principles.Both the qualitative research and quantitative research methodologies must be employed if the desired purposes are to be reached. 展开更多
关键词 English teaching principles Input-output theory Self-efficacy theory PEDAGOGY
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Design and Performance Test of an H-shaped Bionic Piezoelectric Robot Based on the Standing Wave Principle
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作者 Ying Li Chaofeng Li +2 位作者 Zhiwei Wu Binbin Zhu Jinghu Tang 《Journal of Bionic Engineering》 2025年第2期608-625,共18页
In this paper,inspired by the running motion gait of a cheetah,an H-shaped bionic piezoelectric robot(H-BPR)based on the standing wave principle is proposed and designed.The piezoelectric robot realizes linear motion,... In this paper,inspired by the running motion gait of a cheetah,an H-shaped bionic piezoelectric robot(H-BPR)based on the standing wave principle is proposed and designed.The piezoelectric robot realizes linear motion,turning motion,and turning motion with different radi by the voltage differential driving method.A prototype with a weight of 38 g and dimensions of 150×80×31 mm^(3) was fabricated.Firstly,the dynamics and kinematics of the piezoelectric robot were analyzed to obtain the trajectory of a point at the end of the piezoelectric robot leg.The motion principle of the piezo-electric robot was analyzed,and then the piezoelectric robot's modal analysis and harmonic response analysis were carried out using finite element analysis software.Finally,an experimental setup was built to verify the effectiveness and high efficiency of the robot's motion,and the effects of frequency,voltage,load,and height of the driving leg on the robot's motion performance were discussed.The performance test results show that the piezoelectric robot has a maximum veloc-ity of 66.79 mm/s at an excitation voltage of 320 V and a load capacity of 55 g.In addition,the H-BPR with unequal drive legs has better climbing performance,and the obtained conclusions are informative for selecting leg heights for piezoelectric robots. 展开更多
关键词 PIEZOELECTRIC Standing wave principle BIONIC Differential driving method ROBOT
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Exploring Communication in Travel Planning Among Friends: A Case Study Based on the Politeness Principle and Face Theory
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作者 XIE Shu-peng ZHANG Hao-ruo 《Journal of Literature and Art Studies》 2025年第7期594-598,共5页
In interpersonal communication,the principle of politeness is an important communicative principle that is widely applied in people’s daily life.However,the communication patterns of the principle of politeness and f... In interpersonal communication,the principle of politeness is an important communicative principle that is widely applied in people’s daily life.However,the communication patterns of the principle of politeness and face theory in the travel planning process among friends still need further exploration.This study aims to analyze the specific manifestations of these principles in the communication patterns of travel planning among friends through a pragmatic interpretation of the principle of politeness and face theory,providing a new perspective for understanding linguistic behavior in interpersonal relationships. 展开更多
关键词 The Politeness principle FRIENDSHIP face theory travel planning
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