首页 > 最新文献

Latvian Journal of Physics and Technical Sciences最新文献

英文 中文
Energy Performance of Higher Education Institutions Buildings Operating During Quarantine Restrictions and/or Martial Law in Ukraine 乌克兰高等教育机构建筑在检疫限制和/或戒严期间的能效表现
IF 0.6 Q3 Engineering Pub Date : 2024-03-30 DOI: 10.2478/lpts-2024-0012
V. Deshko, I. Bilous, T. Boiko, O. Shevchenko, A. Borodinecs, J. Zemitis
During the pandemic and periods of martial law, educational institutions in Ukraine implemented various forms of organising the educational process, combining in-person and remote classes. As a result, there has been a decrease in the level of use of building premises. The analysis of the characteristics of energy consumption in these conditions requires additional attention. In this study, a dynamic energy model of the building was created using the educational building of Igor Sikorsky Kyiv Polytechnic Institute as an example. Energy consumption for heating needs was determined for normal operating conditions and quarantine conditions in Ukraine (only a specific part of the premises is being operated, ensuring that the standard temperature value is maintained while people are present). Based on the results of the study, the features of the energy consumption of the building during quarantine/martial law restrictions, subject to the partial use of the building, were analysed, and the main disadvantages of such a mode were identified. For the educational building of the university, the total energy consumption for heating needs depends on the number of rooms that are actively used, and the modes of regulation of heating and ventilation; the consumption can decrease depending on the chosen scenario by 61 %, 56 %, and 34 % in quarantine mode. The findings indicate that the efficiency of regulation modes can decrease by more than four times when compared to normal mode due to internal heat exchange with unoccupied rooms.
在大流行病和戒严期间,乌克兰的教育机构采取了多种形式组织教学过程,将现场授课和远程授课相结合。因此,校舍的使用率有所下降。分析这些条件下的能源消耗特点需要更多关注。本研究以伊戈尔-西科斯基基辅理工学院的教学楼为例,建立了楼宇动态能源模型。确定了正常运行条件下和乌克兰检疫条件下的供暖能耗(仅运行校舍的特定部分,确保在有人在场的情况下保持标准温度值)。根据研究结果,分析了检疫/军法限制期间部分使用建筑物的能源消耗特点,并确定了这种模式的主要缺点。对于该大学的教学楼而言,供暖所需的总能耗取决于积极使用的房间数量以及供暖和通风的调节模式;在检疫模式下,能耗可根据所选方案分别减少 61%、56% 和 34%。研究结果表明,与正常模式相比,由于与闲置房间进行内部热交换,调节模式的效率可降低四倍以上。
{"title":"Energy Performance of Higher Education Institutions Buildings Operating During Quarantine Restrictions and/or Martial Law in Ukraine","authors":"V. Deshko, I. Bilous, T. Boiko, O. Shevchenko, A. Borodinecs, J. Zemitis","doi":"10.2478/lpts-2024-0012","DOIUrl":"https://doi.org/10.2478/lpts-2024-0012","url":null,"abstract":"\u0000 During the pandemic and periods of martial law, educational institutions in Ukraine implemented various forms of organising the educational process, combining in-person and remote classes. As a result, there has been a decrease in the level of use of building premises. The analysis of the characteristics of energy consumption in these conditions requires additional attention. In this study, a dynamic energy model of the building was created using the educational building of Igor Sikorsky Kyiv Polytechnic Institute as an example. Energy consumption for heating needs was determined for normal operating conditions and quarantine conditions in Ukraine (only a specific part of the premises is being operated, ensuring that the standard temperature value is maintained while people are present). Based on the results of the study, the features of the energy consumption of the building during quarantine/martial law restrictions, subject to the partial use of the building, were analysed, and the main disadvantages of such a mode were identified. For the educational building of the university, the total energy consumption for heating needs depends on the number of rooms that are actively used, and the modes of regulation of heating and ventilation; the consumption can decrease depending on the chosen scenario by 61 %, 56 %, and 34 % in quarantine mode. The findings indicate that the efficiency of regulation modes can decrease by more than four times when compared to normal mode due to internal heat exchange with unoccupied rooms.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140364205","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}
引用次数: 0
Injection of Renewables Gases Into the Existing Gas Distribution Grids and Employment of Reverse Gas Flow Technique 将可再生能源气体注入现有配气网并采用气体逆向流动技术
IF 0.6 Q3 Engineering Pub Date : 2024-03-30 DOI: 10.2478/lpts-2024-0013
L. Jansons, J. Silina, I. Bode, L. Zemite, N. Zeltiņš, K. Palkova
Sustainability and longevity of existing gas grid exploitation perspective are closely related to two fundamental issues: their ability to adopt to changing gas fuel production and supply landscape in the context of methane-based fuels, mostly, biomethane, and in the context of non-methane-based fuels, mostly, low carbon and green hydrogen. Renewable gases and their ever-growing presence in gas transmission and distribution systems open up a discussion about the necessity to revise and restructure the original – vertically integrated layout of the gas systems, where gas supply is only technically possible from the transmission system towards distribution one, and not vice versa. Development of numerous decentralized biomethane production facilities connected to the gas distribution system causes a necessity to ensure the possibility to pass biomethane surplus of a certain production area into the gas transmission grid, thus avoiding necessity to install biomethane storage capacities locally and granting other regions an opportunity to use said surplus in their gas consumption immediately. The article addresses biomethane production trends and actions taken towards the development of reverse flow gas stations in France – one of biggest biomethane producers in Europe to date, and opportunities and challenges, which this technique might face in smaller and less active renewable gas markets as the one of Latvia.
现有气网开发的可持续性和寿命与两个基本问题密切相关:在甲烷基燃料(主要是生物甲烷)和非甲烷基燃料(主要是低碳和绿色氢气)的背景下,它们适应不断变化的气体燃料生产和供应环境的能力。可再生气体及其在天然气输配系统中日益增长的存在,引发了对修改和重组天然气系统原始垂直一体化布局必要性的讨论,在这种布局中,天然气供应在技术上只能从输气系统向配气系统进行,而不能从配气系统向输气系统进行。大量分散的生物甲烷生产设施与天然气输送系统相连接,这就需要确保将某一生产地区的剩余生物甲烷输送到天然气输送网络,从而避免在当地安装生物甲烷储存设施,并使其他地区有机会立即将剩余生物甲烷用于天然气消费。文章介绍了法国--迄今为止欧洲最大的生物甲烷生产国之一--的生物甲烷生产趋势和为发展反向流动气站所采取的行动,以及在拉脱维亚这样规模较小、不太活跃的可再生天然气市场中,该技术可能面临的机遇和挑战。
{"title":"Injection of Renewables Gases Into the Existing Gas Distribution Grids and Employment of Reverse Gas Flow Technique","authors":"L. Jansons, J. Silina, I. Bode, L. Zemite, N. Zeltiņš, K. Palkova","doi":"10.2478/lpts-2024-0013","DOIUrl":"https://doi.org/10.2478/lpts-2024-0013","url":null,"abstract":"\u0000 Sustainability and longevity of existing gas grid exploitation perspective are closely related to two fundamental issues: their ability to adopt to changing gas fuel production and supply landscape in the context of methane-based fuels, mostly, biomethane, and in the context of non-methane-based fuels, mostly, low carbon and green hydrogen. Renewable gases and their ever-growing presence in gas transmission and distribution systems open up a discussion about the necessity to revise and restructure the original – vertically integrated layout of the gas systems, where gas supply is only technically possible from the transmission system towards distribution one, and not vice versa. Development of numerous decentralized biomethane production facilities connected to the gas distribution system causes a necessity to ensure the possibility to pass biomethane surplus of a certain production area into the gas transmission grid, thus avoiding necessity to install biomethane storage capacities locally and granting other regions an opportunity to use said surplus in their gas consumption immediately. The article addresses biomethane production trends and actions taken towards the development of reverse flow gas stations in France – one of biggest biomethane producers in Europe to date, and opportunities and challenges, which this technique might face in smaller and less active renewable gas markets as the one of Latvia.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363803","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}
引用次数: 0
Analysis of the Energy Consumption for Heating in Schools 学校供暖能耗分析
IF 0.6 Q3 Engineering Pub Date : 2024-03-30 DOI: 10.2478/lpts-2024-0014
M. Sinakovics, A. Zajacs, A. Palcikovskis, V. Jacnevs
The aim of the study is to analyse energy consumption for heating in set of the school buildings. Data analysis includes three data sets – predictions from energy performance certificates (EPC), measured data from heat meters and measured climate corrected data. Data sets were statistically checked and processed and represented graphically. The actual energy consumption differs from the one stated in the EPCs in all cases, which means that schools consume on average 15 % more energy than it is stated in the EPC. Overall, the data reveal that the actual energy consumption differs from the theoretical consumption, with all schools having higher actual consumption than the theoretical values. The differences in the data sets are discussed, and possible improvements are suggested taking into account strong relation between energy consumption and indoor air quality.
研究的目的是分析学校建筑供暖的能源消耗情况。数据分析包括三组数据--能源性能证书(EPC)预测数据、热量表测量数据和气候校正测量数据。数据集经过统计检查和处理,并以图形表示。在所有情况下,实际能耗都与 EPC 中的数据不同,这意味着学校的平均能耗比 EPC 中的数据高出 15%。总体而言,数据显示实际能耗与理论能耗不同,所有学校的实际能耗都高于理论值。对数据集的差异进行了讨论,并考虑到能耗与室内空气质量之间的密切关系,提出了可能的改进建议。
{"title":"Analysis of the Energy Consumption for Heating in Schools","authors":"M. Sinakovics, A. Zajacs, A. Palcikovskis, V. Jacnevs","doi":"10.2478/lpts-2024-0014","DOIUrl":"https://doi.org/10.2478/lpts-2024-0014","url":null,"abstract":"\u0000 The aim of the study is to analyse energy consumption for heating in set of the school buildings. Data analysis includes three data sets – predictions from energy performance certificates (EPC), measured data from heat meters and measured climate corrected data. Data sets were statistically checked and processed and represented graphically. The actual energy consumption differs from the one stated in the EPCs in all cases, which means that schools consume on average 15 % more energy than it is stated in the EPC. Overall, the data reveal that the actual energy consumption differs from the theoretical consumption, with all schools having higher actual consumption than the theoretical values. The differences in the data sets are discussed, and possible improvements are suggested taking into account strong relation between energy consumption and indoor air quality.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363384","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}
引用次数: 0
Enhanced-Reach Polarization Optical Time-Domain Reflectometry Technique for Fibre Optical Infrastructure Monitoring 用于光纤基础设施监测的增强型偏振光时域反射测量技术
IF 0.6 Q3 Engineering Pub Date : 2024-03-30 DOI: 10.2478/lpts-2024-0011
J. Braunfelds, S. Spolitis, D. Cirjulina, A. Ostrovskis, J. Porins, L. Gegere, A. Supe
This interdisciplinary research is focused on constructing and demonstrating enhanced-reach polarization optical time-domain reflectometer (POTDR) for monitoring single-mode fibre optical communication lines. An optical signal state of polarization measurements enables several new possibilities for real-time monitoring solutions in fibre optics. However, there is no commercial equipment available to determine the location in fibre optical cable where the light polarization state changes. The authors present a monitoring technique of an optical signal state of polarization based on reflected signal time-amplitude analysis with improved operation parameters, namely, timing resolution (2 to 3 ps RMS) and amplitude measurement resolution of nanosecond scale pulses (8 to 10 bits) for monitoring of fibre optical communication lines. Additionally, the demonstrated POTDR provides a considerable optical fibre line measurement reach of up to 40 km.
这项跨学科研究的重点是构建和演示用于监测单模光纤通信线路的增强型偏振光时域反射仪(POTDR)。偏振光信号状态测量为光纤实时监测解决方案提供了多种新的可能性。然而,目前还没有商用设备可用于确定光偏振态变化在光纤电缆中的位置。作者介绍了一种基于反射信号时幅分析的光信号偏振态监测技术,该技术改进了操作参数,即用于监测光纤通信线路的时间分辨率(2 至 3 ps RMS)和纳秒级脉冲的振幅测量分辨率(8 至 10 位)。此外,已演示的 POTDR 可提供长达 40 千米的光纤线路测量范围。
{"title":"Enhanced-Reach Polarization Optical Time-Domain Reflectometry Technique for Fibre Optical Infrastructure Monitoring","authors":"J. Braunfelds, S. Spolitis, D. Cirjulina, A. Ostrovskis, J. Porins, L. Gegere, A. Supe","doi":"10.2478/lpts-2024-0011","DOIUrl":"https://doi.org/10.2478/lpts-2024-0011","url":null,"abstract":"\u0000 This interdisciplinary research is focused on constructing and demonstrating enhanced-reach polarization optical time-domain reflectometer (POTDR) for monitoring single-mode fibre optical communication lines. An optical signal state of polarization measurements enables several new possibilities for real-time monitoring solutions in fibre optics. However, there is no commercial equipment available to determine the location in fibre optical cable where the light polarization state changes. The authors present a monitoring technique of an optical signal state of polarization based on reflected signal time-amplitude analysis with improved operation parameters, namely, timing resolution (2 to 3 ps RMS) and amplitude measurement resolution of nanosecond scale pulses (8 to 10 bits) for monitoring of fibre optical communication lines. Additionally, the demonstrated POTDR provides a considerable optical fibre line measurement reach of up to 40 km.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140364341","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}
引用次数: 0
Red Persistent Luminescence and Trap Properties of Mg2SiO4: Mn2+, M3+ (M3+ = B3+; Al3+; Ga3+; In3+) Material Mg2SiO4: Mn2+, M3+ (M3+ = B3+; Al3+; Ga3+; In3+) 材料的红色持久发光和阱特性
IF 0.6 Q3 Engineering Pub Date : 2024-03-30 DOI: 10.2478/lpts-2024-0008
G. Doke
Persistent luminescence (PersL), also called long-lasting phosphorescence or simply afterglow, is a luminescence characterised by the emission of radiation from a few seconds to several days after the excitation source has been switched off. Over the past two decades, research on PersL materials, both in fundamental and applied physics, has developed rapidly; however, the explanation for the physical processes that cause afterglow still needs to be clarified. Today, PersL materials are used mainly for luminescent paints, safety signs and decorations. At the same time, research into using such materials in medicine, information storage, anti-counterfeiting technology, etc., is underway. Currently, information on the long persistent luminescence materials with emission in the blue and green spectral range is widely available. In contrast, the number of publications on the afterglow in the red and near-infrared spectral range is considerably lower. Within the framework of this research, Mg2SiO4: Mn2+; M3+ (M3+ = B3+; Al3+; Ga3+; In3+) materials were synthesised using solid state reaction synthesis. When excited with X-rays, the materials exhibited a broad Mn2+ PersL band with two maxima at approximately 625 nm and 730 nm. After cessation of irradiation, an afterglow of at least 6 hours could be observed. The research focuses on the trap properties of the materials. It was concluded that at least three discrete trap levels with activation energies approximately between 0.4–1.6 eV were present in the samples. Additionally, co-doping with Al3+; Ga3+; In3+ ions improved PersL longevity of the Mg2SiO4: Mn2+ material.
持续发光(PersL),又称长效磷光或简单的余辉,是一种发光现象,其特点是在激发光源关闭后的几秒钟到几天内发射辐射。在过去的二十年里,有关 PersL 材料的基础物理学和应用物理学研究都得到了快速发展;然而,对引起余辉的物理过程的解释仍有待澄清。如今,PersL 材料主要用于发光涂料、安全标志和装饰品。与此同时,在医药、信息存储、防伪技术等领域使用此类材料的研究也在进行之中。目前,有关在蓝色和绿色光谱范围内发光的长持续发光材料的信息已经非常广泛。相比之下,有关红色和近红外光谱范围内余辉的出版物数量要少得多。在本研究框架内,采用固态反应合成法合成了 Mg2SiO4: Mn2+; M3+ (M3+ = B3+; Al3+; Ga3+; In3+) 材料。在 X 射线激发下,这些材料显示出宽阔的 Mn2+ PersL 波段,在大约 625 纳米和 730 纳米处有两个最大值。停止照射后,可观察到至少 6 小时的余辉。研究的重点是材料的阱特性。研究得出结论,样品中至少存在三个离散的阱层,其活化能大约在 0.4-1.6 eV 之间。此外,Al3+、Ga3+、In3+ 离子的共同掺杂提高了 Mg2SiO4: Mn2+ 材料的 PersL 寿命。
{"title":"Red Persistent Luminescence and Trap Properties of Mg2SiO4: Mn2+, M3+ (M3+ = B3+; Al3+; Ga3+; In3+) Material","authors":"G. Doke","doi":"10.2478/lpts-2024-0008","DOIUrl":"https://doi.org/10.2478/lpts-2024-0008","url":null,"abstract":"\u0000 Persistent luminescence (PersL), also called long-lasting phosphorescence or simply afterglow, is a luminescence characterised by the emission of radiation from a few seconds to several days after the excitation source has been switched off. Over the past two decades, research on PersL materials, both in fundamental and applied physics, has developed rapidly; however, the explanation for the physical processes that cause afterglow still needs to be clarified. Today, PersL materials are used mainly for luminescent paints, safety signs and decorations. At the same time, research into using such materials in medicine, information storage, anti-counterfeiting technology, etc., is underway.\u0000 Currently, information on the long persistent luminescence materials with emission in the blue and green spectral range is widely available. In contrast, the number of publications on the afterglow in the red and near-infrared spectral range is considerably lower.\u0000 Within the framework of this research, Mg2SiO4: Mn2+; M3+ (M3+ = B3+; Al3+; Ga3+; In3+) materials were synthesised using solid state reaction synthesis. When excited with X-rays, the materials exhibited a broad Mn2+ PersL band with two maxima at approximately 625 nm and 730 nm. After cessation of irradiation, an afterglow of at least 6 hours could be observed.\u0000 The research focuses on the trap properties of the materials. It was concluded that at least three discrete trap levels with activation energies approximately between 0.4–1.6 eV were present in the samples. Additionally, co-doping with Al3+; Ga3+; In3+ ions improved PersL longevity of the Mg2SiO4: Mn2+ material.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140363343","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}
引用次数: 0
The First Application of Laser-Induced Breakdown Spectroscopy: A Fast-Analytical Technique in Targeted Search for Elements in Geological Samples from Deep Boreholes in Latvia 激光诱导击穿光谱的首次应用:拉脱维亚深孔地质样本中元素定向搜索的快速分析技术
IF 0.6 Q3 Engineering Pub Date : 2024-03-30 DOI: 10.2478/lpts-2024-0010
R. A. Ganeev, V. V. Kim, D. Vorobyov, U. Gross, A. Ubelis, D. Ozols, J. Butikova, J. Grube, A. Sarakovskis
Laser-induced breakdown spectroscopy (LIBS) provides a rapid, cost-effective, and extra-sensitive analysis of geological samples to make preliminary conclusions about the presence of valuable elements up to the trace levels in the ore. We present the first results of a highly sensitive qualitative analysis of the core samples of geological ore from two boreholes in Latvia (Staicele 1, from a depth range of 794–802 m, and Garsene (Subate) 2A, from a depth range of 1102–1103 m) using LIBS. Our measurements using this technique confirmed the high iron content and indicated traces of rare and high in-demand metals (such as Ti, V, Co, Sm, etc.) in the sample from Staicele, renewing interest in studying boreholes across Latvia. The presented pilot studies demonstrated effectiveness and unique possibility in performing a very sensitive and time-saving qualitative analysis of the composition of samples of ores from the old but still valuable borehole cores by using the LIBS method. We compare these measurements with other methods of sample analysis.
激光诱导击穿光谱(LIBS)可以对地质样本进行快速、经济、超灵敏的分析,从而对矿石中是否存在痕量有价元素做出初步结论。我们首次介绍了利用 LIBS 对拉脱维亚两个钻孔(深度范围为 794-802 米的 Staicele 1 和深度范围为 1102-1103 米的 Garsene (Subate) 2A)的地质矿石岩心样品进行高灵敏度定性分析的结果。我们利用该技术进行的测量确认了铁含量较高,并显示了来自 Staicele 的样本中稀有和高需求金属(如钛、钒、钴、钐等)的踪迹,重新激发了对拉脱维亚各地钻孔进行研究的兴趣。所介绍的试点研究表明,使用 LIBS 方法对来自古老但仍有价值的钻孔岩心的矿石样本进行非常灵敏和省时的定性分析是有效和独特的。我们将这些测量结果与其他样品分析方法进行了比较。
{"title":"The First Application of Laser-Induced Breakdown Spectroscopy: A Fast-Analytical Technique in Targeted Search for Elements in Geological Samples from Deep Boreholes in Latvia","authors":"R. A. Ganeev, V. V. Kim, D. Vorobyov, U. Gross, A. Ubelis, D. Ozols, J. Butikova, J. Grube, A. Sarakovskis","doi":"10.2478/lpts-2024-0010","DOIUrl":"https://doi.org/10.2478/lpts-2024-0010","url":null,"abstract":"\u0000 Laser-induced breakdown spectroscopy (LIBS) provides a rapid, cost-effective, and extra-sensitive analysis of geological samples to make preliminary conclusions about the presence of valuable elements up to the trace levels in the ore. We present the first results of a highly sensitive qualitative analysis of the core samples of geological ore from two boreholes in Latvia (Staicele 1, from a depth range of 794–802 m, and Garsene (Subate) 2A, from a depth range of 1102–1103 m) using LIBS. Our measurements using this technique confirmed the high iron content and indicated traces of rare and high in-demand metals (such as Ti, V, Co, Sm, etc.) in the sample from Staicele, renewing interest in studying boreholes across Latvia. The presented pilot studies demonstrated effectiveness and unique possibility in performing a very sensitive and time-saving qualitative analysis of the composition of samples of ores from the old but still valuable borehole cores by using the LIBS method. We compare these measurements with other methods of sample analysis.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140364027","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}
引用次数: 0
General and Complete Synchronization of Mutual Coupling System of Quantum Dot Semiconductor Lasers With Optical Feedback 带光反馈的量子点半导体激光器相互耦合系统的一般和完全同步化
IF 0.6 Q3 Engineering Pub Date : 2024-02-01 DOI: 10.2478/lpts-2024-0007
O. H. Abdulkareem, R. H. Abdali, B. A. Ghalib
The study examines an extensive and complete synchronization of optimal feedback with quantum dot semiconductor laser mutual coupling system. This has been achieved by resolving the transmitter and receiver equations of the quantum dot lasers. Numerous crisis areas have been observed at the time of investigating the relationship between photon density and time. The authors have selected an optimal time delay for the optical feedback so as to render an appropriate situation for intermittent dynamics. The study analyses the impact created by a long external cavity of QDSL upon the synchronization process in this mutual coupling system, in the presence of the enhancement factor of (α =3).
该研究探讨了量子点半导体激光器相互耦合系统的广泛而完整的最佳同步反馈。这是通过解析量子点激光器的发射器和接收器方程实现的。在研究光子密度与时间的关系时,发现了许多危机区域。作者为光反馈选择了一个最佳的时间延迟,以便为间歇动力学提供一个合适的环境。研究分析了在增强因子(α =3)存在的情况下,QDSL 的长外腔对这种相互耦合系统的同步过程产生的影响。
{"title":"General and Complete Synchronization of Mutual Coupling System of Quantum Dot Semiconductor Lasers With Optical Feedback","authors":"O. H. Abdulkareem, R. H. Abdali, B. A. Ghalib","doi":"10.2478/lpts-2024-0007","DOIUrl":"https://doi.org/10.2478/lpts-2024-0007","url":null,"abstract":"\u0000 The study examines an extensive and complete synchronization of optimal feedback with quantum dot semiconductor laser mutual coupling system. This has been achieved by resolving the transmitter and receiver equations of the quantum dot lasers. Numerous crisis areas have been observed at the time of investigating the relationship between photon density and time. The authors have selected an optimal time delay for the optical feedback so as to render an appropriate situation for intermittent dynamics. The study analyses the impact created by a long external cavity of QDSL upon the synchronization process in this mutual coupling system, in the presence of the enhancement factor of (α =3).","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139824153","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}
引用次数: 0
A Practical Solution to Reduce Interference from Led Lights 减少 LED 灯干扰的实用解决方案
IF 0.6 Q3 Engineering Pub Date : 2024-02-01 DOI: 10.2478/lpts-2024-0004
J. Kallunki
The study explores the detection of a harmful, wide-band interference signal, whose origin is a traditional desk LED (light-emitting diode) lamp. The interference signal was noticed on the sensitive solar spectrometer observing system, which was operating at a frequency range between 100 and 300 MHz. The interference signal was so strong and wide-band that it destroyed totally the solar observations. The study introduces two practical EMI (Electromagnetic Interference) reducing methods: ferrite cores and shielding (shielding effectiveness, S.E.). Their theoretical background is presented, and, in addition, these methods are tested in practice. The measurements and tests showed that even simple ferrite core was a very effective method to reduce interference effects. It is important that a suitable setup will be found: a single ferrite core cannot solve a whole problem. This interference problem is very demonstrative and it can be used in educational purposes at an undergraduate level at Metropolia University of Applied Sciences, Finland. This study reveals the fact that standard lamps, which are on the market, do not necessarily follow good EMC (Electromagnetic Compatibility) practices.
该研究探讨了有害宽带干扰信号的探测,其来源是传统的台式 LED(发光二极管)灯。在敏感的太阳光谱仪观测系统上发现了干扰信号,该系统的工作频率范围在 100 至 300 兆赫之间。干扰信号的强度和频带非常大,完全破坏了太阳观测。研究介绍了两种实用的 EMI(电磁干扰)减弱方法:铁氧体磁芯和屏蔽(屏蔽效能,S.E.)。介绍了它们的理论背景,并对这些方法进行了实际测试。测量和测试表明,即使是简单的铁氧体磁芯也是一种非常有效的降低干扰效应的方法。重要的是要找到合适的设置:单个铁氧体磁芯不能解决全部问题。这个干扰问题具有很强的示范性,可用于芬兰 Metropolia 应用科学大学本科阶段的教育目的。这项研究揭示了一个事实,即市场上的标准灯具并不一定符合良好的电磁兼容性(EMC)规范。
{"title":"A Practical Solution to Reduce Interference from Led Lights","authors":"J. Kallunki","doi":"10.2478/lpts-2024-0004","DOIUrl":"https://doi.org/10.2478/lpts-2024-0004","url":null,"abstract":"\u0000 The study explores the detection of a harmful, wide-band interference signal, whose origin is a traditional desk LED (light-emitting diode) lamp. The interference signal was noticed on the sensitive solar spectrometer observing system, which was operating at a frequency range between 100 and 300 MHz. The interference signal was so strong and wide-band that it destroyed totally the solar observations. The study introduces two practical EMI (Electromagnetic Interference) reducing methods: ferrite cores and shielding (shielding effectiveness, S.E.). Their theoretical background is presented, and, in addition, these methods are tested in practice. The measurements and tests showed that even simple ferrite core was a very effective method to reduce interference effects. It is important that a suitable setup will be found: a single ferrite core cannot solve a whole problem. This interference problem is very demonstrative and it can be used in educational purposes at an undergraduate level at Metropolia University of Applied Sciences, Finland. This study reveals the fact that standard lamps, which are on the market, do not necessarily follow good EMC (Electromagnetic Compatibility) practices.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139875641","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}
引用次数: 0
Exposure Buildup Factors in Concrete, Lead for Point Isotropic and Unidirectional Photon Sources in the Energy Range from 10 to 50 MeV 10 至 50 MeV 能量范围内各向同性点光子源和单向光子源在混凝土、铅中的辐照堆积因子
IF 0.6 Q3 Engineering Pub Date : 2024-02-01 DOI: 10.2478/lpts-2024-0002
I. Alhagaish, A. K. Aqili
The exposure buildup factors in concrete and lead for a point isotropic and flat unidirectional photon source in the energy range from 10 to 50 MeV were determined using Monte Carlo simulation “FLUKA” software. The exposure buildup factors were also obtained for different material thickness up to 40 mpf. The calculations were done in a barrier geometry where the contributions of all photon-matter interactions were taken into account in the performed calculations. Amendments for the barrier-geometry effect for both materials under study were deduced. The results showed that barrier-effect amendments were independent of the material thickness, material type, and energy of the photon source
使用蒙特卡洛模拟软件 "FLUKA "确定了能量范围为 10 至 50 MeV 的点各向同性和平面单向光子源在混凝土和铅中的辐照堆积因子。此外,还获得了不同材料厚度(最高达 40 mpf)下的辐照积累因子。计算是在势垒几何中进行的,在计算中考虑了所有光子-物质相互作用的贡献。推导出了所研究的两种材料的阻挡几何效应修正值。结果表明,阻挡效应修正与材料厚度、材料类型和光子源能量无关。
{"title":"Exposure Buildup Factors in Concrete, Lead for Point Isotropic and Unidirectional Photon Sources in the Energy Range from 10 to 50 MeV","authors":"I. Alhagaish, A. K. Aqili","doi":"10.2478/lpts-2024-0002","DOIUrl":"https://doi.org/10.2478/lpts-2024-0002","url":null,"abstract":"\u0000 The exposure buildup factors in concrete and lead for a point isotropic and flat unidirectional photon source in the energy range from 10 to 50 MeV were determined using Monte Carlo simulation “FLUKA” software. The exposure buildup factors were also obtained for different material thickness up to 40 mpf. The calculations were done in a barrier geometry where the contributions of all photon-matter interactions were taken into account in the performed calculations. Amendments for the barrier-geometry effect for both materials under study were deduced. The results showed that barrier-effect amendments were independent of the material thickness, material type, and energy of the photon source","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139828774","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}
引用次数: 0
Sodium Citrate and Polyvinylpyrrolidone Captured Silver Nanoparticles Transfer to Organic Solvents 柠檬酸钠和聚乙烯吡咯烷酮捕获的银纳米粒子向有机溶剂转移
IF 0.6 Q3 Engineering Pub Date : 2024-02-01 DOI: 10.2478/lpts-2024-0003
J. Mikelsone, A. Vembris
Silver nanoparticles (NPs) have gathered extensive attention due to their properties – chemical stability, good conductivity, catalytic activity, and antimicrobial activity. This makes NPs suitable for potential applications in the development of new technologies in the field of photonics, electronics, medicine, biochemical sensing, and imaging. Nanoprisms have local surface plasmon resonance starting from visible to near infra-red spectrum, broadening the possibilities of their applications. Ag NPs typically are synthesized in aqueous solution but the handling of NPs often requires their dispersion into nonpolar solvents and their mixing with organic compounds. Thus, nanoparticle transfer to organic media is essential for application in the field of emission enhancement due to NPs – organic semiconductor interaction. A shell changing method for NP tranfer was successfully used with a high transfer rate, but rather low stability. The previously proposed sonochemical method for NP transfer from aqueous to organic polymeric media is extended to different organic solvents. The ultrasonic method is suitable to obtain stable NPs in both organic solvent and organic solvent/organic compound solutions, and it can be stored at ambient conditions for at least several months. Transfer efficiency is suficient and NPs remain stable in an organic solvent like chlorobenzene, anisole, dichloromethane. The method has potential in NPs containing thin film preparation because sonication prevents the agglomeration of clusters.
银纳米粒子(NPs)因其化学稳定性、良好的导电性、催化活性和抗菌活性等特性而受到广泛关注。这使得银纳米粒子在光子学、电子学、医学、生化传感和成像领域的新技术开发中具有潜在的应用价值。纳米粒子具有从可见光到近红外光谱的局部表面等离子体共振,这拓宽了其应用的可能性。银纳米粒子通常在水溶液中合成,但在处理纳米粒子时往往需要将其分散到非极性溶剂中,并与有机化合物混合。因此,将纳米粒子转移到有机介质中对于纳米粒子-有机半导体相互作用导致的发射增强领域的应用至关重要。一种用于纳米粒子转移的换壳法已成功应用,该方法转移率高,但稳定性较低。之前提出的将 NP 从水性介质转移到有机聚合物介质的超声化学方法被扩展到不同的有机溶剂中。该超声波方法适用于在有机溶剂和有机溶剂/有机化合物溶液中获得稳定的 NP,并可在环境条件下保存至少数月。转移效率足够高,NPs 在氯苯、苯甲醚、二氯甲烷等有机溶剂中保持稳定。该方法具有制备含 NPs 薄膜的潜力,因为超声可防止团聚。
{"title":"Sodium Citrate and Polyvinylpyrrolidone Captured Silver Nanoparticles Transfer to Organic Solvents","authors":"J. Mikelsone, A. Vembris","doi":"10.2478/lpts-2024-0003","DOIUrl":"https://doi.org/10.2478/lpts-2024-0003","url":null,"abstract":"\u0000 Silver nanoparticles (NPs) have gathered extensive attention due to their properties – chemical stability, good conductivity, catalytic activity, and antimicrobial activity. This makes NPs suitable for potential applications in the development of new technologies in the field of photonics, electronics, medicine, biochemical sensing, and imaging. Nanoprisms have local surface plasmon resonance starting from visible to near infra-red spectrum, broadening the possibilities of their applications. Ag NPs typically are synthesized in aqueous solution but the handling of NPs often requires their dispersion into nonpolar solvents and their mixing with organic compounds. Thus, nanoparticle transfer to organic media is essential for application in the field of emission enhancement due to NPs – organic semiconductor interaction. A shell changing method for NP tranfer was successfully used with a high transfer rate, but rather low stability. The previously proposed sonochemical method for NP transfer from aqueous to organic polymeric media is extended to different organic solvents. The ultrasonic method is suitable to obtain stable NPs in both organic solvent and organic solvent/organic compound solutions, and it can be stored at ambient conditions for at least several months. Transfer efficiency is suficient and NPs remain stable in an organic solvent like chlorobenzene, anisole, dichloromethane. The method has potential in NPs containing thin film preparation because sonication prevents the agglomeration of clusters.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139880655","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}
引用次数: 0
期刊
Latvian Journal of Physics and Technical Sciences
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1