The auto-combustion technique was employed to synthesize nano particles of BxFe(3−x)O4 (x = 0.0, 0.7, 1.18, 1.36 and 1.54). The resulting structural and dielectric properties of the boron doped Fe3O4 were evaluated. XRD analysis confirmed the presence of a single spinel structure with crystallite dimensions ranging from 21.18 to 26.43 nm and lattice parameters of 8.211 to 8.487 Ǻ. The morphological images revealed homogenous and spherical grain sizes, while EDX confirmed the presence of constituent elements used. The X-ray density increased whereas the bulk density and the porosity decreased with boron substitution. The study of dielectric properties and AC conductivity (σAC) was demonstrated and the AC conductivity decreased with increasing boron concentration, indicating a hopping mechanism. Moreover, noticeable variations in dielectric loss, AC conductivity, and dielectric permittivity with temperature and frequency were observed. These observations were attributed to the Maxwell–Wagner interfacial polarization and the hopping of charges between Fe3+ and Fe2+ ions.
{"title":"Structural and temperature dependent dielectric behaviour of BxFe(3−x)O4 nanoferrite particles","authors":"Paramesh Donta","doi":"10.1049/mna2.12194","DOIUrl":"https://doi.org/10.1049/mna2.12194","url":null,"abstract":"<p>The auto-combustion technique was employed to synthesize nano particles of B<i><sub>x</sub></i>Fe<sub>(3−</sub><i><sub>x</sub></i><sub>)</sub>O<sub>4</sub> (<i>x</i> = 0.0, 0.7, 1.18, 1.36 and 1.54). The resulting structural and dielectric properties of the boron doped Fe<sub>3</sub>O<sub>4</sub> were evaluated. XRD analysis confirmed the presence of a single spinel structure with crystallite dimensions ranging from 21.18 to 26.43 nm and lattice parameters of 8.211 to 8.487 Ǻ. The morphological images revealed homogenous and spherical grain sizes, while EDX confirmed the presence of constituent elements used. The X-ray density increased whereas the bulk density and the porosity decreased with boron substitution. The study of dielectric properties and AC conductivity (<i>σ<sub>AC</sub></i>) was demonstrated and the AC conductivity decreased with increasing boron concentration, indicating a hopping mechanism. Moreover, noticeable variations in dielectric loss, AC conductivity, and dielectric permittivity with temperature and frequency were observed. These observations were attributed to the Maxwell–Wagner interfacial polarization and the hopping of charges between Fe<sup>3+</sup> and Fe<sup>2+</sup> ions.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12194","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140333003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joshua Neilson, Veronica Granata, Ofelia Durante, Christopher Ausbeck, Timothy F. Bennett, Fabrizio Bobba, Marco Cannavacciuolo, Giovanni Carapella, Francesco Chiadini, Riccardo DeSalvo, Roberta De Simone, Cinzia Di Giorgio, Rosalba Fittipaldi, Vincenzo Fiumara, Brecken Larsen, Tugdual LeBohec, Seth Linker, Alberto Micco, Marina Mondin, Bhavna Nayak, Antonio Vecchione, Innocenzo M. Pinto, Vincenzo Pierro
In many physics and engineering applications requiring exceptional precision, the presence of highly reflective coatings with low thermal noise is of utmost significance. These applications include high-resolution spectroscopy, optical atomic clocks, and investigations into fundamental physics such as gravitational wave detection. Enhancing sensitivity in these experiments relies on effectively reducing the thermal noise originating from the coatings. While ion beam sputtering (IBS) is typically employed for fabricating such coatings, electron beam evaporation can also be utilized and offers certain advantages over IBS, such as versatility and speed. However, a significant challenge in the fabrication process has been the limitations of the quartz crystal monitor used to measure the thickness of the deposited layers. This paper showcases how, through hardware and software upgrades, it becomes achievable to create high-density coatings with layers as thin as a few angstroms by using electron beam evaporation (OAC75F coater) with a deposition rate of 1 Å/s and ion-assisted source with a gas mixture of oxygen and argon, using a pressure of about 4 × 10−4 mbar. Furthermore, these upgrades enable the attainment of high levels of precision and uniformity in the thickness of the coatings.
{"title":"Optimizing nanostructure deposition process for optical applications","authors":"Joshua Neilson, Veronica Granata, Ofelia Durante, Christopher Ausbeck, Timothy F. Bennett, Fabrizio Bobba, Marco Cannavacciuolo, Giovanni Carapella, Francesco Chiadini, Riccardo DeSalvo, Roberta De Simone, Cinzia Di Giorgio, Rosalba Fittipaldi, Vincenzo Fiumara, Brecken Larsen, Tugdual LeBohec, Seth Linker, Alberto Micco, Marina Mondin, Bhavna Nayak, Antonio Vecchione, Innocenzo M. Pinto, Vincenzo Pierro","doi":"10.1049/mna2.12186","DOIUrl":"https://doi.org/10.1049/mna2.12186","url":null,"abstract":"<p>In many physics and engineering applications requiring exceptional precision, the presence of highly reflective coatings with low thermal noise is of utmost significance. These applications include high-resolution spectroscopy, optical atomic clocks, and investigations into fundamental physics such as gravitational wave detection. Enhancing sensitivity in these experiments relies on effectively reducing the thermal noise originating from the coatings. While ion beam sputtering (IBS) is typically employed for fabricating such coatings, electron beam evaporation can also be utilized and offers certain advantages over IBS, such as versatility and speed. However, a significant challenge in the fabrication process has been the limitations of the quartz crystal monitor used to measure the thickness of the deposited layers. This paper showcases how, through hardware and software upgrades, it becomes achievable to create high-density coatings with layers as thin as a few angstroms by using electron beam evaporation (OAC75F coater) with a deposition rate of 1 Å/s and ion-assisted source with a gas mixture of oxygen and argon, using a pressure of about 4 × 10<sup>−4</sup> mbar. Furthermore, these upgrades enable the attainment of high levels of precision and uniformity in the thickness of the coatings.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 2","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140135345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The quasi-Z-source H-bridge grid-connected inverter (QHGCI) is well known for its advantages of the void of the shoot-through problem and the high DC-voltage utilization. But the existence of the common-mode leakage current in the power frequency cycle, lower power density, and higher thermal stress make it hard applicable to the grid-penetrating application. Thus with the purpose to conquer the problem relating to the QHGCI, an innovative transformerless Z-source photovoltaic grid-connected inverter with a coupled inductor coil (TZPGCI-CIC) is proposed. The circuitry topology and an unipolar sine pulse width modulation strategy are first introduced in short. Thereafter, the common-mode voltage in the whole working process is derived and evaluated through the detailed operating mode analysis, in which a constant value of it has been theoretically revealed. Lastly, a prototype platform of TZPGCI-CIC is set up and its good performance on leakage current suppression, and lower thermal stress are validated with the experimental results.
准 Z 源 H 桥并网逆变器(QHGCI)因其不存在击穿问题和直流电压利用率高的优点而广为人知。但是,由于在电源频率周期内存在共模漏电流、功率密度较低以及热应力较大等问题,它很难适用于穿透电网的应用。因此,为了解决与 QHGCI 相关的问题,我们提出了一种创新型无变压器 Z 源光伏并网逆变器(TZPGCI-CIC)。首先简要介绍了电路拓扑结构和单极性正弦脉宽调制策略。随后,通过详细的工作模式分析,得出并评估了整个工作过程中的共模电压,并从理论上揭示了其恒定值。最后,建立了 TZPGCI-CIC 原型平台,并通过实验结果验证了其在抑制漏电流和降低热应力方面的良好性能。
{"title":"A transformerless Z-source photovoltaic grid-connected inverter with coupled inductor coil","authors":"Yunzhong Dai, Huaiyu Zhang","doi":"10.1049/mna2.12193","DOIUrl":"https://doi.org/10.1049/mna2.12193","url":null,"abstract":"<p>The quasi-Z-source H-bridge grid-connected inverter (QHGCI) is well known for its advantages of the void of the shoot-through problem and the high DC-voltage utilization. But the existence of the common-mode leakage current in the power frequency cycle, lower power density, and higher thermal stress make it hard applicable to the grid-penetrating application. Thus with the purpose to conquer the problem relating to the QHGCI, an innovative transformerless Z-source photovoltaic grid-connected inverter with a coupled inductor coil (TZPGCI-CIC) is proposed. The circuitry topology and an unipolar sine pulse width modulation strategy are first introduced in short. Thereafter, the common-mode voltage in the whole working process is derived and evaluated through the detailed operating mode analysis, in which a constant value of it has been theoretically revealed. Lastly, a prototype platform of TZPGCI-CIC is set up and its good performance on leakage current suppression, and lower thermal stress are validated with the experimental results.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 2","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12193","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140000684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wei Li, Xiaotao Wang, Dan Wu, Dehao Kong, Han Wu, Lai Mang, Bo Liao, O. Tegus, Yongjun Cao, Oimod Haschuluu
The effect of niobium ions with high-valence doping on high-voltage LiNi0.5Mn1.5O4 (LNMO) materials was investigated. LiNi0.5Mn1.5−xNbxO4 was prepared by doping high-valent niobium ions into LiNi0.5Mn1.5O4 material using the organic assisted combustion method. The experimental samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical impedance (EI), and cyclic voltammetry (CV) analysis. The experimental results show that -doping with high-valence niobium ions changes the orientation of the crystal plane growth of spinel particles, and the morphology of these particles changes from the octahedral shape before doping to the spherical shape after doping. With the increase in doping amount, the crystal structure changes gradually, resulting in the Li0.96Nb1.01O3 impurity phase. The doping of high valence-niobium ions increases the content of Mn3+ in the material, resulting in the appearance of a 4 V discharge platform and the formation of a 4.7 and 4 V discharge platforms. The doping of Nb can improve the cycling stability of LiNi0.5Mn1.5O4 material, but the specific capacity of the material is reduced.
{"title":"Study on high voltage (5 V) spinel lithium manganese oxide LiNi0.5Mn1.5O4 by doping niobium","authors":"Wei Li, Xiaotao Wang, Dan Wu, Dehao Kong, Han Wu, Lai Mang, Bo Liao, O. Tegus, Yongjun Cao, Oimod Haschuluu","doi":"10.1049/mna2.12192","DOIUrl":"https://doi.org/10.1049/mna2.12192","url":null,"abstract":"<p>The effect of niobium ions with high-valence doping on high-voltage LiNi<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> (LNMO) materials was investigated. LiNi<sub>0.5</sub>Mn<sub>1.5−</sub><i><sub>x</sub></i>Nb<i><sub>x</sub></i>O<sub>4</sub> was prepared by doping high-valent niobium ions into LiNi<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> material using the organic assisted combustion method. The experimental samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical impedance (EI), and cyclic voltammetry (CV) analysis. The experimental results show that -doping with high-valence niobium ions changes the orientation of the crystal plane growth of spinel particles, and the morphology of these particles changes from the octahedral shape before doping to the spherical shape after doping. With the increase in doping amount, the crystal structure changes gradually, resulting in the Li<sub>0.96</sub>Nb<sub>1.01</sub>O<sub>3</sub> impurity phase. The doping of high valence-niobium ions increases the content of Mn<sup>3+</sup> in the material, resulting in the appearance of a 4 V discharge platform and the formation of a 4.7 and 4 V discharge platforms. The doping of Nb can improve the cycling stability of LiNi<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> material, but the specific capacity of the material is reduced.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 2","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12192","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139993902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mengru Liu, Xiaoxue Du, Jingyi Liu, Guangshuo Wang, Jiajia Yang, Xueling Wang, Shuai Han, Zhongchao Huo
The combination of chemotherapy and photothermal therapy shows great potential in cancer treatment, and the carbon nanomaterials have been attracted great attention in biomedical technology. However, it is still a great challenge to design stimuli-responsive nano-carbon-based drug release systems with integrated functions. In this paper, rod-like carbon nanomaterials (RCNs) were prepared by the soft template hydrothermal method with glucose as raw materials, which were proved to have high photothermal efficiency (∼23.7%), as well as good biocompatibility and excellent drug-loading capacity. After that, RCNs were used to load doxorubicin (DOX) as DOX@RCNs for integrated photothermal/chemotherapy towards cancer, which demonstrated 52.2% higher cancer cell killing efficiency than that of RCNs under near infrared (NIR) irradiation in vitro. The authors’ approach provided a novel NIR-responsive nano platform for combined photothermal/chemotherapy towards cancer, which was considered to be of great potential in anticancer applications.
{"title":"Novel rod-like carbon nanomaterials as near infrared-responsive drug delivery system for potential anticancer applications","authors":"Mengru Liu, Xiaoxue Du, Jingyi Liu, Guangshuo Wang, Jiajia Yang, Xueling Wang, Shuai Han, Zhongchao Huo","doi":"10.1049/mna2.12190","DOIUrl":"https://doi.org/10.1049/mna2.12190","url":null,"abstract":"<p>The combination of chemotherapy and photothermal therapy shows great potential in cancer treatment, and the carbon nanomaterials have been attracted great attention in biomedical technology. However, it is still a great challenge to design stimuli-responsive nano-carbon-based drug release systems with integrated functions. In this paper, rod-like carbon nanomaterials (RCNs) were prepared by the soft template hydrothermal method with glucose as raw materials, which were proved to have high photothermal efficiency (∼23.7%), as well as good biocompatibility and excellent drug-loading capacity. After that, RCNs were used to load doxorubicin (DOX) as DOX@RCNs for integrated photothermal/chemotherapy towards cancer, which demonstrated 52.2% higher cancer cell killing efficiency than that of RCNs under near infrared (NIR) irradiation in vitro. The authors’ approach provided a novel NIR-responsive nano platform for combined photothermal/chemotherapy towards cancer, which was considered to be of great potential in anticancer applications.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12190","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139550414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Here, the authors report a practical method for preparing nitrogen-doped carbon materials using an orthogonal array design. The material with the highest specific capacitance value of 262 F·g−1 at a current density of 1 A·g−1 was obtained under the conditions (KOH as activation agent, activation temperature of 600°C, activation time of 3 h, respectively). Its high electrochemical properties are attributed to its high surface area and additional pseudo-capacitance. After 5000 cycles, the specific capacitance remained 92.8%, with good cycle stability. Textural characterization of the carbon materials was performed using N2 adsorption/desorption and scanning electron microscopy.
{"title":"Preparation of nitrogen-doped carbon materials by orthogonal array design for supercapacitors","authors":"Cungui Zhong, Dayong Liu","doi":"10.1049/mna2.12189","DOIUrl":"https://doi.org/10.1049/mna2.12189","url":null,"abstract":"<p>Here, the authors report a practical method for preparing nitrogen-doped carbon materials using an orthogonal array design. The material with the highest specific capacitance value of 262 F·g<sup>−1</sup> at a current density of 1 A·g<sup>−1</sup> was obtained under the conditions (KOH as activation agent, activation temperature of 600°C, activation time of 3 h, respectively). Its high electrochemical properties are attributed to its high surface area and additional pseudo-capacitance. After 5000 cycles, the specific capacitance remained 92.8%, with good cycle stability. Textural characterization of the carbon materials was performed using N<sub>2</sub> adsorption/desorption and scanning electron microscopy.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12189","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139550421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rabiul Awal, Nilufer Yesmin Tanisa, Md. Arifur Rahman, Shamim Ahmed
In this investigation, a nanostructured Cu2O thin film absorber layer is electrodeposited, exploring the impact of varying negative applied voltages and deposition time. Notably, the Cu2O thin film demonstrated optimal absorbance at −0.95 V, contrasting sharply with a minimum at −0.97 V. The authors' findings underscore that the peak absorbance was achieved at −0.95 V, coinciding with the lowest transmittance observed after 80 min of deposition, aligning with a maximal absorption coefficient of 21 × 103 cm−1. At a deposition time of 5 min, the Cu2O thin film exhibited a noteworthy maximum Urbach energy of 2.00 eV and a minimum steepness parameter of 0.013. In contrast, the lowest Urbach energy was recorded at 0.34 eV, with the highest steepness parameter occurring at an applied voltage of 0.93 V. Furthermore, this study revealed a gradual increase in the refractive index with higher applied voltages, reaching its pinnacle at −1.5 V. These results collectively emphasize the nuanced interplay between applied voltage, deposition time and the optical properties of the nanostructured Cu2O thin film. The observed trends hold significant implications for optimizing the performance of thin film absorber layers, particularly in the context of enhancing absorbance and tailoring optical characteristics for specific applications.
在这项研究中,电沉积了纳米结构的 Cu2O 薄膜吸收层,探讨了不同负电压和沉积时间的影响。值得注意的是,Cu2O 薄膜在 -0.95 V 时显示出最佳吸光度,与 -0.97 V 时的最低吸光度形成鲜明对比。作者的研究结果强调,吸光度峰值出现在 -0.95 V,与沉积 80 分钟后观察到的最低透射率相吻合,与 21 × 103 cm-1 的最大吸收系数相一致。沉积时间为 5 分钟时,Cu2O 薄膜显示出值得注意的 2.00 eV 最大乌巴赫能和 0.013 最小陡度参数。相反,最低的乌巴赫能为 0.34 eV,最高的陡度参数出现在 0.93 V 的施加电压下。此外,这项研究还发现,折射率随着施加电压的升高而逐渐增加,在-1.5 V时达到顶峰。这些结果共同强调了施加电压、沉积时间和纳米结构 Cu2O 薄膜光学特性之间微妙的相互作用。观察到的趋势对优化薄膜吸收层的性能具有重要意义,特别是在提高吸收率和为特定应用定制光学特性方面。
{"title":"Preparation of nanostructured cuprous oxide (Cu2O) absorber layer for photovoltaic application","authors":"Rabiul Awal, Nilufer Yesmin Tanisa, Md. Arifur Rahman, Shamim Ahmed","doi":"10.1049/mna2.12188","DOIUrl":"https://doi.org/10.1049/mna2.12188","url":null,"abstract":"<p>In this investigation, a nanostructured Cu<sub>2</sub>O thin film absorber layer is electrodeposited, exploring the impact of varying negative applied voltages and deposition time. Notably, the Cu<sub>2</sub>O thin film demonstrated optimal absorbance at −0.95 V, contrasting sharply with a minimum at −0.97 V. The authors' findings underscore that the peak absorbance was achieved at −0.95 V, coinciding with the lowest transmittance observed after 80 min of deposition, aligning with a maximal absorption coefficient of 21 × 10<sup>3</sup> cm<sup>−1</sup>. At a deposition time of 5 min, the Cu<sub>2</sub>O thin film exhibited a noteworthy maximum Urbach energy of 2.00 eV and a minimum steepness parameter of 0.013. In contrast, the lowest Urbach energy was recorded at 0.34 eV, with the highest steepness parameter occurring at an applied voltage of 0.93 V. Furthermore, this study revealed a gradual increase in the refractive index with higher applied voltages, reaching its pinnacle at −1.5 V. These results collectively emphasize the nuanced interplay between applied voltage, deposition time and the optical properties of the nanostructured Cu<sub>2</sub>O thin film. The observed trends hold significant implications for optimizing the performance of thin film absorber layers, particularly in the context of enhancing absorbance and tailoring optical characteristics for specific applications.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12188","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139473905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Feng Bu, Rui Feng, Shuwen Guo, Ming Zhou, Yiwang Wang, Feng Wang
Micro-electro-mechanical system gyroscope detection output is susceptible to drift due to ambient temperature variations. Furthermore, the drive-mode vibration amplitude is affected by the signal pickup circuit and structural parameters, which significantly influence the temperature drift of the bias and scale factor (SF). This study proposes a vibration amplitude control method based on harmonic amplitude sideband-ratio (SBR), namely SBR-AGC, which characterizes the vibration amplitude using the harmonic amplitude ratio of the vibrational electrical signal. The constancy of vibration amplitude is maintained via closed-loop control to suppress bias and SF temperature drift. The experimental results on cobweb-like disk resonator gyroscope reveal that the temperature coefficient of bias in the SBR-AGC mode lies within −20 to 60°C and decreases by 36%, and the temperature coefficient of the SF lies within −10 to 50°C and decreases by 49.7%. Therefore, the environmental adaptability of the gyroscope is effectively improved.
微机电系统陀螺仪的检测输出易受环境温度变化的影响而发生漂移。此外,驱动模式的振动幅度会受到信号拾取电路和结构参数的影响,从而对偏置和比例因子(SF)的温度漂移产生重大影响。本研究提出了一种基于谐波振幅边带比(SBR)的振动振幅控制方法,即 SBR-AGC,它利用振动电信号的谐波振幅比来表征振动振幅。通过闭环控制来抑制偏差和 SF 温度漂移,从而保持振动振幅的恒定性。蛛网状圆盘谐振器陀螺仪的实验结果表明,在 SBR-AGC 模式下,偏压的温度系数在 -20 至 60°C 范围内下降了 36%,而 SF 的温度系数在 -10 至 50°C 范围内下降了 49.7%。因此,陀螺仪的环境适应性得到了有效改善。
{"title":"Temperature drift suppression for micro-electro-mechanical system gyroscope based on vibrational-displacement control with harmonic amplitude ratio","authors":"Feng Bu, Rui Feng, Shuwen Guo, Ming Zhou, Yiwang Wang, Feng Wang","doi":"10.1049/mna2.12187","DOIUrl":"https://doi.org/10.1049/mna2.12187","url":null,"abstract":"<p>Micro-electro-mechanical system gyroscope detection output is susceptible to drift due to ambient temperature variations. Furthermore, the drive-mode vibration amplitude is affected by the signal pickup circuit and structural parameters, which significantly influence the temperature drift of the bias and scale factor (SF). This study proposes a vibration amplitude control method based on harmonic amplitude sideband-ratio (SBR), namely SBR-AGC, which characterizes the vibration amplitude using the harmonic amplitude ratio of the vibrational electrical signal. The constancy of vibration amplitude is maintained via closed-loop control to suppress bias and SF temperature drift. The experimental results on cobweb-like disk resonator gyroscope reveal that the temperature coefficient of bias in the SBR-AGC mode lies within −20 to 60°C and decreases by 36%, and the temperature coefficient of the SF lies within −10 to 50°C and decreases by 49.7%. Therefore, the environmental adaptability of the gyroscope is effectively improved.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12187","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139109767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the separation and determination of trace amounts of drugs in aqueous samples, there is a major challenge in synthesizing highly efficient, cost-effective, and easy-to-use adsorbents based on natural polymers, which are also biocompatible and biodegradable. In the proposed method, magnetite nanoparticles (Fe3O4) on chitosan (as the carrier) modified with β-cyclodextrin (BCD) were used as a suitable adsorbent for the pre-concentration and solid-phase extraction of trace amounts of Amitriptyline HCl (hydrochloride). Ultraviolet spectrophotometer (λ = 236 nm) was the main instrument used for analyte detection and quantification. Moreover, X-ray diffraction, Fourier transform infrared spectroscopy, Field Emission Scanning Electron Microscopy, and Energy-Dispersive X-ray were used for the identification and characterization of the structure and morphology of the adsorbent and to establish the formation of the synthesized magnetic nanosorbents, as well as to confirm the analyte binding to the adsorbent. Experimental variables affecting the extraction/pre-concentration and determination of the analyte were investigated and optimized; pH of the sample solution, the amount of NaCl salt (in terms of ionic strength of the solution), the amount of adsorbent, temperature, adsorption time, and volume of the eluent (methanol) were the optimized parameters. Finally, the method was successfully applied for the determination of spiked Amitriptyline hydrochloride (HCl) in tap water and human urine samples. Also, High-Performance Liquid Chromatography was performed on the aqueous samples to compare the proposed method with the USP (the United States Pharmacopeia) standard method of Amitriptyline HCl assay and after performing a t-test (confidence level of 95%), no significant difference was observed between the two methods. High accuracy and precision (RSD = 3.91%), High analysis speed, few limitations, low expenses, pure extracted analyte, and low waste were the advantages of this method. This method was also compatible with many existing device methods. Under the optimized experimental conditions, the calibration graph was linear in the range of 0.183 to 50 mg.L−1 with a correlation coefficient of 0.996. RSD of the method was 3.91%, the limit of detection was 37.8 µg.L−1, the maximum sorption capacity of the adsorbent for Amitriptyline hydrochloride was 306.525 mg.g−1 and the preconcentration factor was 3.61. Eventually, the proposed method was compared to other methods that have been performed for the determination of Amitriptyline hydrochloride.
{"title":"Preconcentration and measurement of trace Amitriptyline hydrochloride in water samples using magnetic nanoparticles with dispersive solid-phase extraction","authors":"Arghavan Amin, Ali Moghimi","doi":"10.1049/mna2.12184","DOIUrl":"https://doi.org/10.1049/mna2.12184","url":null,"abstract":"<p>In the separation and determination of trace amounts of drugs in aqueous samples, there is a major challenge in synthesizing highly efficient, cost-effective, and easy-to-use adsorbents based on natural polymers, which are also biocompatible and biodegradable. In the proposed method, magnetite nanoparticles (Fe<sub>3</sub>O<sub>4</sub>) on chitosan (as the carrier) modified with β-cyclodextrin (BCD) were used as a suitable adsorbent for the pre-concentration and solid-phase extraction of trace amounts of Amitriptyline HCl (hydrochloride). Ultraviolet spectrophotometer (λ = 236 nm) was the main instrument used for analyte detection and quantification. Moreover, X-ray diffraction, Fourier transform infrared spectroscopy, Field Emission Scanning Electron Microscopy, and Energy-Dispersive X-ray were used for the identification and characterization of the structure and morphology of the adsorbent and to establish the formation of the synthesized magnetic nanosorbents, as well as to confirm the analyte binding to the adsorbent. Experimental variables affecting the extraction/pre-concentration and determination of the analyte were investigated and optimized; pH of the sample solution, the amount of NaCl salt (in terms of ionic strength of the solution), the amount of adsorbent, temperature, adsorption time, and volume of the eluent (methanol) were the optimized parameters. Finally, the method was successfully applied for the determination of spiked Amitriptyline hydrochloride (HCl) in tap water and human urine samples. Also, High-Performance Liquid Chromatography was performed on the aqueous samples to compare the proposed method with the USP (the United States Pharmacopeia) standard method of Amitriptyline HCl assay and after performing a <i>t</i>-test (confidence level of 95%), no significant difference was observed between the two methods. High accuracy and precision (RSD = 3.91%), High analysis speed, few limitations, low expenses, pure extracted analyte, and low waste were the advantages of this method. This method was also compatible with many existing device methods. Under the optimized experimental conditions, the calibration graph was linear in the range of 0.183 to 50 mg.L<sup>−1</sup> with a correlation coefficient of 0.996. RSD of the method was 3.91%, the limit of detection was 37.8 µg.L<sup>−1</sup>, the maximum sorption capacity of the adsorbent for Amitriptyline hydrochloride was 306.525 mg.g<sup>−1</sup> and the preconcentration factor was 3.61. Eventually, the proposed method was compared to other methods that have been performed for the determination of Amitriptyline hydrochloride.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12184","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139042302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Liver cancer is one of the most common causes of death all around the globe. On the other hand, conventional modalities, such as chemotherapy and surgery, have not been effectively suppressed cancer incidence due to some deficiencies. As a result, a novel folic acid (FA)-decorated poly lactic-co-glycolic acid (PLGA)-Alginate (Alg) nanocarrier was efficiently developed for active doxorubicin (Dox) delivery to human HepG2 liver cancer cells. The in vitro assays, including cell viability assay (MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test), apoptosis, cell cycle arrest, and cellular uptake, were applied to evaluate the cancer cell growth suppression and apoptosis-inducing ability of the nanocarrier. More than 85% cytotoxicity was attained after 24 h of treatment with 400-nM concentration of FA-PLGA-Dox-Alg. More than 21% and 61% apoptosis were observed after 24 h of treatment with 100-nM concentrations of FA-PLGA-Dox-Alg in apoptosis and cell cycle arrest assays. The cellular uptake of the FA-PLGA-Alg nanocarrier was about 30% higher than that of the PLGA-Alg carrier which indicated the cancer cell targeting ability of the FA-PLGA-Alg sample. These results have indicated the potential capability of FA-PLGA-Dox-Alg in the inhibition of liver cancer cells.
{"title":"Biopolymer-based nanoparticles as promising candidate for inducing apoptosis in liver cancer cells","authors":"Mahsa Hoseinzadeh, Mohammad Javad Mokhtari, Farshid Kafilzadeh, Javad Mohammadnejad, Yaghoob Taheri","doi":"10.1049/mna2.12183","DOIUrl":"10.1049/mna2.12183","url":null,"abstract":"<p>Liver cancer is one of the most common causes of death all around the globe. On the other hand, conventional modalities, such as chemotherapy and surgery, have not been effectively suppressed cancer incidence due to some deficiencies. As a result, a novel folic acid (FA)-decorated poly lactic-co-glycolic acid (PLGA)-Alginate (Alg) nanocarrier was efficiently developed for active doxorubicin (Dox) delivery to human HepG2 liver cancer cells. The in vitro assays, including cell viability assay (MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test), apoptosis, cell cycle arrest, and cellular uptake, were applied to evaluate the cancer cell growth suppression and apoptosis-inducing ability of the nanocarrier. More than 85% cytotoxicity was attained after 24 h of treatment with 400-nM concentration of FA-PLGA-Dox-Alg. More than 21% and 61% apoptosis were observed after 24 h of treatment with 100-nM concentrations of FA-PLGA-Dox-Alg in apoptosis and cell cycle arrest assays. The cellular uptake of the FA-PLGA-Alg nanocarrier was about 30% higher than that of the PLGA-Alg carrier which indicated the cancer cell targeting ability of the FA-PLGA-Alg sample. These results have indicated the potential capability of FA-PLGA-Dox-Alg in the inhibition of liver cancer cells.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12183","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138822562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}