Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6259
Yeming Xian, Xiaoming Wang, Yanfa Yan
Metal halide perovskites (MHPs) are excellent semiconductors that have led to breakthroughs in applications in thin-film solar cells, detectors, and light-emitting diodes due to their remarkable optoelectronic properties and defect tolerance. However, the performance and stability of MHPbased devices are significantly influenced by their microstructures including the formation of defects, composition fluctuations, structural inhomogeneity, etc. Transmission electron microscopy (TEM) is a powerful tool for direct observation of microstructural at the atomicscale resolution and has been used to correlate the microstructure and performance of MHPbased devices. In this review, we highlight the application of TEM techniques in revealing the microstructures of MHP thin films at the atomic scale. The results provide critical understanding of the performance of MHP devices and guide the design of strategies for improving the performance and stability of MHP devices.
{"title":"Revealing the microstructures of metal halide perovskite thin films via advanced transmission electron microscopy","authors":"Yeming Xian, Xiaoming Wang, Yanfa Yan","doi":"10.1088/1674-1056/ad6259","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6259","url":null,"abstract":"\u0000 Metal halide perovskites (MHPs) are excellent semiconductors that have led to breakthroughs in applications in thin-film solar cells, detectors, and light-emitting diodes due to their remarkable optoelectronic properties and defect tolerance. However, the performance and stability of MHPbased devices are significantly influenced by their microstructures including the formation of defects, composition fluctuations, structural inhomogeneity, etc. Transmission electron microscopy (TEM) is a powerful tool for direct observation of microstructural at the atomicscale resolution and has been used to correlate the microstructure and performance of MHPbased devices. In this review, we highlight the application of TEM techniques in revealing the microstructures of MHP thin films at the atomic scale. The results provide critical understanding of the performance of MHP devices and guide the design of strategies for improving the performance and stability of MHP devices.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"22 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6254
Wanting Zhang, Rong Xu, Wendong Ma, Zhao Lin, Kai Yang, Bing Yuan
Membrane tension plays a crucial role in various fundamental cellular processes, with one notable example being the T cell-mediated elimination of tumor cells through perforin-induced membrane perforation by amplifying cellular force. However, the mechanisms governing the regulation of biomolecular activities at the cell interface by membrane tension remain elusive. In this study, we investigated the correlation between membrane tension and poration activity of melittin, a prototypical pore-forming peptide, using dynamic giant unilamellar vesicle leakage assays combined with flickering tension analysis, molecular dynamics simulations, and live cell assays. The results demonstrate that an increase in membrane tension enhances the activity of melittin, particularly near its critical pore-forming concentration. Moreover, peptide actions such as binding, insertion, and aggregation in the membrane further influence the evolution of membrane tension. Live cell experiments reveal that artificially enhancing membrane tension effectively enhances melittin's ability to induce pore formation and disrupt membranes, resulting in up to a ten-fold increase in A549 cell mortality when exposed to a concentration of 2.0 μg mL-1 melittin. Our findings elucidate the relationship between membrane tension and the mechanism of action as well as pore-forming efficiency of melittin, while providing a practical mechanical approach for regulating functional activity of molecules at the cell-membrane interface.
膜张力在各种基本细胞过程中发挥着至关重要的作用，其中一个显著的例子是 T 细胞通过穿孔素诱导的膜穿孔放大细胞力来消除肿瘤细胞。然而，膜张力对细胞界面上生物分子活动的调控机制仍然难以捉摸。在这项研究中，我们利用动态巨型单拉美拉尔囊泡渗漏试验，结合闪烁张力分析、分子动力学模拟和活细胞试验，研究了膜张力与美利汀（一种典型的孔形成肽）的穿孔活性之间的相关性。结果表明，膜张力的增加会增强美利汀的活性，尤其是在其临界孔形成浓度附近。此外，肽在膜中的结合、插入和聚集等作用也会进一步影响膜张力的演变。活细胞实验显示，人为提高膜张力可有效增强美利汀诱导孔形成和破坏膜的能力，当暴露于浓度为 2.0 μg mL-1 的美利汀时，A549 细胞的死亡率最多可增加十倍。我们的研究结果阐明了膜张力与美利汀的作用机制及孔隙形成效率之间的关系，同时为调节细胞-膜界面分子的功能活性提供了一种实用的机械方法。
{"title":"Membrane tension evolution and mechanical regulation of melittin-induced membrane poration","authors":"Wanting Zhang, Rong Xu, Wendong Ma, Zhao Lin, Kai Yang, Bing Yuan","doi":"10.1088/1674-1056/ad6254","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6254","url":null,"abstract":"\u0000 Membrane tension plays a crucial role in various fundamental cellular processes, with one notable example being the T cell-mediated elimination of tumor cells through perforin-induced membrane perforation by amplifying cellular force. However, the mechanisms governing the regulation of biomolecular activities at the cell interface by membrane tension remain elusive. In this study, we investigated the correlation between membrane tension and poration activity of melittin, a prototypical pore-forming peptide, using dynamic giant unilamellar vesicle leakage assays combined with flickering tension analysis, molecular dynamics simulations, and live cell assays. The results demonstrate that an increase in membrane tension enhances the activity of melittin, particularly near its critical pore-forming concentration. Moreover, peptide actions such as binding, insertion, and aggregation in the membrane further influence the evolution of membrane tension. Live cell experiments reveal that artificially enhancing membrane tension effectively enhances melittin's ability to induce pore formation and disrupt membranes, resulting in up to a ten-fold increase in A549 cell mortality when exposed to a concentration of 2.0 μg mL-1 melittin. Our findings elucidate the relationship between membrane tension and the mechanism of action as well as pore-forming efficiency of melittin, while providing a practical mechanical approach for regulating functional activity of molecules at the cell-membrane interface.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"46 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad625b
Bing Hao, Jingjing Guo, Peizhi Liu, Junjie Guo
Electrocatalytic water splitting for hydrogen production is an appealing strategy to reduce carbon emissions and generate renewable fuels. This promising process, however, is limited by its sluggish reaction kinetics and high-cost catalysts. The two- dimensional (2D) transition metal dichalcogenides (TMDCs) have presented great potential as electrocatalytic materials due to their tunable bandgaps, abundant defective active sites, and good chemical stability. Consequently, phase engineering, defect engineering and interface engineering have been adopted to manipulate the electronic structure of TMDCs for boosting their exceptional catalytic performance. Particularly, it is essential to clarify the local structure of catalytically active sites of TMDCs and their structural evolution in catalytic reactions, using atomic resolution electron microscopy and the booming in situ technologies, which is beneficial for exploring the underlying reaction mechanism. In this review, the growth regulation, characterization, particularly atomic configurations of active sites in TMDCs were summarized. The significant role of electron microscopy for the understanding of the growth mechanism, the controlled synthesis and functional optimization of 2D TMDCs are discussed. This review will shed lights on the design and synthesis of novel electrocatalysts with high performance, as well as prompt the application of advanced electron microscopy in the research of materials science.
{"title":"Electronic structure engineering of transition metal dichalcogenides for boosting hydrogen energy conversion electrocatalysts","authors":"Bing Hao, Jingjing Guo, Peizhi Liu, Junjie Guo","doi":"10.1088/1674-1056/ad625b","DOIUrl":"https://doi.org/10.1088/1674-1056/ad625b","url":null,"abstract":"\u0000 Electrocatalytic water splitting for hydrogen production is an appealing strategy to reduce carbon emissions and generate renewable fuels. This promising process, however, is limited by its sluggish reaction kinetics and high-cost catalysts. The two- dimensional (2D) transition metal dichalcogenides (TMDCs) have presented great potential as electrocatalytic materials due to their tunable bandgaps, abundant defective active sites, and good chemical stability. Consequently, phase engineering, defect engineering and interface engineering have been adopted to manipulate the electronic structure of TMDCs for boosting their exceptional catalytic performance. Particularly, it is essential to clarify the local structure of catalytically active sites of TMDCs and their structural evolution in catalytic reactions, using atomic resolution electron microscopy and the booming in situ technologies, which is beneficial for exploring the underlying reaction mechanism.\u0000 In this review, the growth regulation, characterization, particularly atomic configurations of active sites in TMDCs were summarized. The significant role of electron microscopy for the understanding of the growth mechanism, the controlled synthesis and functional optimization of 2D TMDCs are discussed. This review will shed lights on the design and synthesis of novel electrocatalysts with high performance, as well as prompt the application of advanced electron microscopy in the research of materials science.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"13 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6251
Yuheng Shan, An Li, Xinyun Zhang, Wen Yi, Ying Zhang, Xiaodong Liu, Ruibin Liu
The matrix thermal properties have an important impact on laser induced plasma, as the thermal effect dominates the interaction between ns-pulsed laser and matter, especially in metals. We used a series of pure metals and aluminum alloys to measure plasma temperature and electron density through laser-induced breakdown spectroscopy, in order to investigate the effect of matrix thermal properties on laser induced plasma. In pure metals, a significant negative linear correlation was observed between the matrix thermal storage coefficient and plasma temperature, while a weak correlation was observed with electron density. The results indicate that metals with low thermal conductivity or specific heat capacity require less laser energy for thermal diffusion or melting and evaporation, resulting in higher ablation rates and higher plasma temperatures. However, considering ionization energy, thermal effects may be a secondary factor affecting electron density. The experiment of aluminum alloy further confirms the influence of thermal conductivity on plasma temperature and its mechanism explanation.
{"title":"Effect of Matrix Thermal Properties on Laser Induced Plasma","authors":"Yuheng Shan, An Li, Xinyun Zhang, Wen Yi, Ying Zhang, Xiaodong Liu, Ruibin Liu","doi":"10.1088/1674-1056/ad6251","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6251","url":null,"abstract":"\u0000 The matrix thermal properties have an important impact on laser induced plasma, as the thermal effect dominates the interaction between ns-pulsed laser and matter, especially in metals. We used a series of pure metals and aluminum alloys to measure plasma temperature and electron density through laser-induced breakdown spectroscopy, in order to investigate the effect of matrix thermal properties on laser induced plasma. In pure metals, a significant negative linear correlation was observed between the matrix thermal storage coefficient and plasma temperature, while a weak correlation was observed with electron density. The results indicate that metals with low thermal conductivity or specific heat capacity require less laser energy for thermal diffusion or melting and evaporation, resulting in higher ablation rates and higher plasma temperatures. However, considering ionization energy, thermal effects may be a secondary factor affecting electron density. The experiment of aluminum alloy further confirms the influence of thermal conductivity on plasma temperature and its mechanism explanation.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"5 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141652328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad624e
A. Alnahdi, T. Gul
Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal conductivity. Heat exchangers, cooling systems, and other thermal management systems are ideal for the use of Casson fluid. Controlling medication flow and release with precision is necessary when using Casson fluids in drug delivery systems because of their unique rheological properties. Nanotechnology involves the creation of nanoparticles that are loaded with drugs and distributed in Casson fluid-based carriers for targeted delivery. To create a hybrid nanofluid in this study, both single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are dispersed in the Casson fluid with Fourier's and Fick's laws assumptions. The Casson fluid is suitable for various engineering and medical applications due to the enhancement of heat transfer and thermal conductivity by carbon nanotubes. Our objective is to understand how SWCNTs and MWCNTs impact the flow field by studying the flow behavior of the Casson hybrid nanofluid when it is stretched against a Riga plate. The DarcyForchheimer model is also used to account for the impact of the porous medium near the stretching plate. Both linear and quadratic drag terms are taken into account in this model to accurately predict the flow behavior of the nanofluid. In addition, the homotopy analysis method (HAM) is utilized to address the model problem. The outcomes are discussed and deliberated based on drug delivery applications. These findings shed valuable light on the flow characteristics of the Casson hybrid nanofluid comprised of SWCNTs and MWCNTs.It is observed that the incorporation of CNTs makes the nanofluid a promising candidate for medical applications due to its improved heat transfer properties.
{"title":"Casson Hybrid Nanofluids Flow Over a Riga Plate for the Drug Delivery Applications with Double Diffusion","authors":"A. Alnahdi, T. Gul","doi":"10.1088/1674-1056/ad624e","DOIUrl":"https://doi.org/10.1088/1674-1056/ad624e","url":null,"abstract":"\u0000 Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal conductivity. Heat exchangers, cooling systems, and other thermal management systems are ideal for the use of Casson fluid. Controlling medication flow and release with precision is necessary when using Casson fluids in drug delivery systems because of their unique rheological properties. Nanotechnology involves the creation of nanoparticles that are loaded with drugs and distributed in Casson fluid-based carriers for targeted delivery.\u0000 To create a hybrid nanofluid in this study, both single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are dispersed in the Casson fluid with Fourier's and Fick's laws assumptions. The Casson fluid is suitable for various engineering and medical applications due to the enhancement of heat transfer and thermal conductivity by carbon nanotubes.\u0000 Our objective is to understand how SWCNTs and MWCNTs impact the flow field by studying the flow behavior of the Casson hybrid nanofluid when it is stretched against a Riga plate. The DarcyForchheimer model is also used to account for the impact of the porous medium near the stretching plate. Both linear and quadratic drag terms are taken into account in this model to accurately predict the flow behavior of the nanofluid. In addition, the homotopy analysis method (HAM) is utilized to address the model problem. The outcomes are discussed and deliberated based on drug delivery applications. These findings shed valuable light on the flow characteristics of the Casson hybrid nanofluid comprised of SWCNTs and MWCNTs.It is observed that the incorporation of CNTs makes the nanofluid a promising candidate for medical applications due to its improved heat transfer properties.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"84 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad624f
Siyu Jian, Siying Long, Juhua Chen, Yong-jiu Wang
In this paper, we study the thermodynamics of charged AdS black hole surrounded by quintessence in a new formalism which is called the restricted phase space thermodynamics(RPST). This context is based on the Visser's holographic thermodynamics with a fixed Anti-de Sitter radius and a variable Newton constant. The conjugate variables central charge $C$ and the chemical potential $mu$ are introduced as a new pair of thermodynamic variables. We have found that the iso-e-charge $T-S$ curve becomes non-monotonic when $hat{Q}＜hat{Q}_{c}$. And correspondingly, the $F-T$ curve exhibits a swallow tail structure. This behavior is considered as a Van der Waals-like phase transition. As the value of $hat{b}$ related to the energy density of Kiselev's fluid gets larger, the critical temperature $T_c$ will decrease. So the Van der Waals-like phase transition will occure at lower temperature. There is always a non-quilibrium transition from a small unstable black hole to a large stable black hole state in the isocoltage $T-S$ process. And there contains a maximuma and a Hawking-Page phase transition point in the $mu-C$ plane. As the value of $hat{b}$ related to Kiselev's fluid gets larger, the Hawking-Page phase transition will occur at the lower temperature in the isovoltage $mu-T$ process. For the other values of the state parameter $omega$, there also exists Van der Waals-like phase transition.
{"title":"Thermodynamics of charged AdS black hole surrounded by quintessence in restricted phase space","authors":"Siyu Jian, Siying Long, Juhua Chen, Yong-jiu Wang","doi":"10.1088/1674-1056/ad624f","DOIUrl":"https://doi.org/10.1088/1674-1056/ad624f","url":null,"abstract":"\u0000 In this paper, we study the thermodynamics of charged AdS black hole surrounded by quintessence in a new formalism which is called the restricted phase space thermodynamics(RPST). This context is based on the Visser's holographic thermodynamics with a fixed Anti-de Sitter radius and a variable Newton constant. The conjugate variables central charge $C$ and the chemical potential $mu$ are introduced as a new pair of thermodynamic variables. We have found that the iso-e-charge $T-S$ curve becomes non-monotonic when $hat{Q}＜hat{Q}_{c}$. And correspondingly, the $F-T$ curve exhibits a swallow tail structure. This behavior is considered as a Van der Waals-like phase transition. As the value of $hat{b}$ related to the energy density of Kiselev's fluid gets larger, the critical temperature $T_c$ will decrease. So the Van der Waals-like phase transition will occure at lower temperature. There is always a non-quilibrium transition from a small unstable black hole to a large stable black hole state in the isocoltage $T-S$ process. And there contains a maximuma and a Hawking-Page phase transition point in the $mu-C$ plane. As the value of $hat{b}$ related to Kiselev's fluid gets larger, the Hawking-Page phase transition will occur at the lower temperature in the isovoltage $mu-T$ process. For the other values of the state parameter $omega$, there also exists Van der Waals-like phase transition.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"54 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141652551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6250
Shi-Bo Li, Si-Yu Xing, F. Gao, You-Nian Wang
The electrical parameters of H2/Ar plasma in a cylindrical inductive discharge with an expansion region are investigated by a Langmuir probe, where Ar fractions range from 0 % to 100 %. The influence of gas composition and pressure on electron density, the effective electron temperature and the electron energy probability functions (EEPFs) at different spatial positions are present. In driver region, with the introduction of a small amount of Ar at 0.3 Pa, there is a rapid increase in electron density accompanied by a decrease in the effective electron temperature. Additionally, the shape of the EEPF transitions from a three-temperature distribution to a bi-Maxwellian distribution due to an increase in electron-electron collision. However, this phenomenon resulting from the changes in gas composition vanishes at 5 Pa duo to the prior depletion of energetic electrons caused by the increase in pressure during hydrogen discharge. The EEPFs for the total energy in expansion region is coincident to these in the driver region at 0.3 Pa, as do the patterns of electron density variation between these two regions for differing Ar fractions. At 5 Pa, as the discharge transitions from H2 to Ar, the EEPFs evolved from a bi-Maxwellian distribution with pronounced low energy electrons to a Maxwellian distribution in expansion region. This evolve may be attributed to a reduction in molecular vibrational excitation reactions of electrons during transport and the transition from localized electron dynamics in hydrogen discharge to non-localized electron dynamics in argon discharge. In order to validate the experimental results, we use the COMSOL simulation software to calculate electrical parameters under the same conditions. The evolution and spatial distribution of the electrical parameters of the simulation results agree well with the trend of the experimental results.
通过朗缪尔探针研究了带膨胀区的圆柱形感应放电中 H2/Ar 等离子体的电参数，其中 Ar 的比例范围为 0 % 至 100 %。气体成分和压力对不同空间位置的电子密度、有效电子温度和电子能量概率函数（EEPFs）都有影响。在驱动区，当引入少量 0.3 Pa 的氩气时，电子密度迅速增加，同时有效电子温度降低。此外，由于电子-电子碰撞的增加，EEPF 的形状也从三温分布转变为双麦克斯韦分布。然而，由于氢放电过程中压力增加导致高能电子耗尽，气体成分变化引起的这一现象在 5 Pa 时消失了。在 0.3 Pa 时，膨胀区总能量的 EEPF 与驱动区的 EEPF 相吻合，这两个区域之间不同 Ar 分数的电子密度变化规律也是如此。在 5 Pa 时，随着放电从 H2 转变为 Ar，EEPFs 从低能电子明显的双麦克斯韦分布演变为膨胀区的麦克斯韦分布。这种演变可能是由于电子在传输过程中的分子振动激发反应减少，以及从氢放电中的局部电子动力学过渡到氩放电中的非局部电子动力学。为了验证实验结果，我们使用 COMSOL 仿真软件计算了相同条件下的电参数。模拟结果中电学参数的演变和空间分布与实验结果的趋势非常吻合。
{"title":"Experimental studies of H2/Ar plasma in a cylindrical inductive discharges with an expansion region","authors":"Shi-Bo Li, Si-Yu Xing, F. Gao, You-Nian Wang","doi":"10.1088/1674-1056/ad6250","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6250","url":null,"abstract":"\u0000 The electrical parameters of H2/Ar plasma in a cylindrical inductive discharge with an expansion region are investigated by a Langmuir probe, where Ar fractions range from 0 % to 100 %. The influence of gas composition and pressure on electron density, the effective electron temperature and the electron energy probability functions (EEPFs) at different spatial positions are present. In driver region, with the introduction of a small amount of Ar at 0.3 Pa, there is a rapid increase in electron density accompanied by a decrease in the effective electron temperature. Additionally, the shape of the EEPF transitions from a three-temperature distribution to a bi-Maxwellian distribution due to an increase in electron-electron collision. However, this phenomenon resulting from the changes in gas composition vanishes at 5 Pa duo to the prior depletion of energetic electrons caused by the increase in pressure during hydrogen discharge. The EEPFs for the total energy in expansion region is coincident to these in the driver region at 0.3 Pa, as do the patterns of electron density variation between these two regions for differing Ar fractions. At 5 Pa, as the discharge transitions from H2 to Ar, the EEPFs evolved from a bi-Maxwellian distribution with pronounced low energy electrons to a Maxwellian distribution in expansion region. This evolve may be attributed to a reduction in molecular vibrational excitation reactions of electrons during transport and the transition from localized electron dynamics in hydrogen discharge to non-localized electron dynamics in argon discharge. In order to validate the experimental results, we use the COMSOL simulation software to calculate electrical parameters under the same conditions. The evolution and spatial distribution of the electrical parameters of the simulation results agree well with the trend of the experimental results.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"42 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6257
Dingkang Mou, Yumin Dong
With the rapid development of digital information technology, images are increasingly used in various fields. To ensure the security of image data, prevent unauthorized tampering and leakage, maintain personal privacy, and protect intellectual property rights, this study proposes an innovative color image encryption algorithm. Initially, the Mersenne Twister algorithm is utilized to generate high-quality pseudo-random numbers, establishing a robust basis for subsequent operations. Subsequently, two distinct chaotic systems, the autonomous non-Hamiltonian chaotic system, and the Tent-Logistic-Cosine chaotic mapping, are employed to produce chaotic random sequences. These chaotic sequences are used to control the encoding and decoding process of the DNA, effectively scrambling the image pixels. Furthermore, the complexity of the encryption process is enhanced through improved Joseph block scrambling. After thorough experimental verification, research, and analysis, the average value of the information entropy test data reaches as high as 7.999. Additionally, the average value of the NPCR test data is 99.6101%, which closely approaches the ideal value of 99.6094%. This algorithm not only guarantees image quality but also substantially raises the difficulty level of decryption.
随着数字信息技术的飞速发展，图像越来越多地应用于各个领域。为了确保图像数据的安全，防止未经授权的篡改和泄漏，维护个人隐私，保护知识产权，本研究提出了一种创新的彩色图像加密算法。首先，利用梅森孪生算法生成高质量的伪随机数，为后续操作建立稳健的基础。随后，利用两个不同的混沌系统，即自主非哈密顿混沌系统和Tent-Logistic-Cosine混沌映射，产生混沌随机序列。这些混沌序列用于控制 DNA 的编码和解码过程，从而有效地扰乱图像像素。此外，通过改进约瑟夫块加扰技术，加密过程的复杂性也得到了提高。经过全面的实验验证、研究和分析，信息熵测试数据的平均值高达 7.999。此外，NPCR 测试数据的平均值为 99.6101%，接近 99.6094% 的理想值。该算法不仅保证了图像质量，还大大提高了解密难度。
{"title":"Image encryption algorithm based on multiple chaotic systems and improved Joseph block scrambling","authors":"Dingkang Mou, Yumin Dong","doi":"10.1088/1674-1056/ad6257","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6257","url":null,"abstract":"\u0000 With the rapid development of digital information technology, images are increasingly used in various fields. To ensure the security of image data, prevent unauthorized tampering and leakage, maintain personal privacy, and protect intellectual property rights, this study proposes an innovative color image encryption algorithm. Initially, the Mersenne Twister algorithm is utilized to generate high-quality pseudo-random numbers, establishing a robust basis for subsequent operations. Subsequently, two distinct chaotic systems, the autonomous non-Hamiltonian chaotic system, and the Tent-Logistic-Cosine chaotic mapping, are employed to produce chaotic random sequences. These chaotic sequences are used to control the encoding and decoding process of the DNA, effectively scrambling the image pixels. Furthermore, the complexity of the encryption process is enhanced through improved Joseph block scrambling. After thorough experimental verification, research, and analysis, the average value of the information entropy test data reaches as high as 7.999. Additionally, the average value of the NPCR test data is 99.6101%, which closely approaches the ideal value of 99.6094%. This algorithm not only guarantees image quality but also substantially raises the difficulty level of decryption.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"45 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6252
Haoguang Liu
We consider a quantum endoreversible Otto engine cycle and its inverse operation-Otto refrigeration cycle, employing two-level systems as the working substance and operating in dual-squeezed reservoirs. We demonstrate that the efficiency of heat engines at maximum work output and the coefficient of performance for refrigerators at the maximum $chi$ criterion will degenerate to $ eta_-=eta_C/(2-eta_C)$ and $ varepsilon_-=(sqrt{9+8varepsilon_C}-3)/2$ when symmetric squeezing is satisfied, respectively. We also investigated the influences of squeezing degree on the performance optimization of quantum Otto heat engines at the maximum work output and refrigerators at the maximum $chi$ criterion. These analytical results show that the efficiency of heat engines at maximum work output and the coefficient of performance for refrigerators at the maximum $chi$ criterion can be improved, reduced or even inhibited in asymmetric squeezing. Furthermore, we also find that the efficiency of quantum Otto heat engines at maximum work output is lower than those obtained from the Otto heat engines based on a single harmonic oscillator system. However, the coefficient of performance of the corresponding refrigerator is higher.
{"title":"Optimization performance of quantum endoreversible Otto machines with dual-squeezed reservoirs","authors":"Haoguang Liu","doi":"10.1088/1674-1056/ad6252","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6252","url":null,"abstract":"\u0000 We consider a quantum endoreversible Otto engine cycle and its inverse operation-Otto refrigeration cycle, employing two-level systems as the working substance and operating in dual-squeezed reservoirs. We demonstrate that the efficiency of heat engines at maximum work output and the coefficient of performance for refrigerators at the maximum $chi$ criterion will degenerate to $ eta_-=eta_C/(2-eta_C)$ and $ varepsilon_-=(sqrt{9+8varepsilon_C}-3)/2$ when symmetric squeezing is satisfied, respectively. We also investigated the influences of squeezing degree on the performance optimization of quantum Otto heat engines at the maximum work output and refrigerators at the maximum $chi$ criterion. These analytical results show that the efficiency of heat engines at maximum work output and the coefficient of performance for refrigerators at the maximum $chi$ criterion can be improved, reduced or even inhibited in asymmetric squeezing. Furthermore, we also find that the efficiency of quantum Otto heat engines at maximum work output is lower than those obtained from the Otto heat engines based on a single harmonic oscillator system. However, the coefficient of performance of the corresponding refrigerator is higher.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"37 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1088/1674-1056/ad6253
Zhi-Peng Yang, Yu-Ran Zhang, Fu-Li Li, Heng Fan
One-way quantum computation focuses on initially generating an entangled cluster state followed by a sequence of measurements with classical communication of their individual outcomes. Recently, a delayed-measurement approach has been applied to replace classical communication of individual measurement outcomes. In this work, by considering the delayed-measurement approach, we demonstrate a modified one-way CNOT gate using the on-cloud superconducting quantum computing platform: Quafu. The modified protocol for one-way quantum computing requires only three qubits rather than the four used in the standard protocol. Since this modified cluster state decreases the number of physical qubits required to implement one-way computation, both the scalability and complexity of the computing process are improved. Compared to previous work, this modified oneway CNOT gate is superior to the standard one in both fidelity and resource requirements. We have also numerically compared the behavior of standard and modified methods in large-scale one-way quantum computing. Our results suggest that in a noisy intermediate-scale quantum (NISQ) era, the modified method shows a significant advantage for one-way quantum computation.
{"title":"Delayed-measurement one-way quantum computing on cloud quantum computer","authors":"Zhi-Peng Yang, Yu-Ran Zhang, Fu-Li Li, Heng Fan","doi":"10.1088/1674-1056/ad6253","DOIUrl":"https://doi.org/10.1088/1674-1056/ad6253","url":null,"abstract":"\u0000 One-way quantum computation focuses on initially generating an entangled cluster state followed by a sequence of measurements with classical communication of their individual outcomes. Recently, a delayed-measurement approach has been applied to replace classical communication of individual measurement outcomes. In this work, by considering the delayed-measurement approach, we demonstrate a modified one-way CNOT gate using the on-cloud superconducting quantum computing platform: Quafu. The modified protocol for one-way quantum computing requires only three qubits rather than the four used in the standard protocol. Since this modified cluster state decreases the number of physical qubits required to implement one-way computation, both the scalability and complexity of the computing process are improved. Compared to previous work, this modified oneway CNOT gate is superior to the standard one in both fidelity and resource requirements. We have also numerically compared the behavior of standard and modified methods in large-scale one-way quantum computing. Our results suggest that in a noisy intermediate-scale quantum (NISQ) era, the modified method shows a significant advantage for one-way quantum computation.","PeriodicalId":504421,"journal":{"name":"Chinese Physics B","volume":"68 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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