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Optical determination of the Boltzmann constant
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作者 程存峰 孙羽 胡水明 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期87-92,共6页
The Boltzmann constant kB is a fundamental physical constant in thermodynamics. The present CODATA recommended value of kB is 1.3806488(13) × 10^-23 J/K (relative uncertainty 0.91 ppm), which is mainly determ... The Boltzmann constant kB is a fundamental physical constant in thermodynamics. The present CODATA recommended value of kB is 1.3806488(13) × 10^-23 J/K (relative uncertainty 0.91 ppm), which is mainly determined by acoustic methods. Doppler broadening thermometry (DBT) is an optical method which determines kBT by measuring the Doppler width of an atomic or molecular transition. The methodology and problems in DBT are reviewed, and DBT measurement using the sensitive cavity ring-down spectroscopy (CRDS) is proposed. Preliminary measurements indicate that CRDS- based DBT measurement can potentially reach an accuracy at the 1 ppm level. 展开更多
关键词 boltzmann constant Doppler broadening thermometry METROLOGY
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The Boltzmann Constant: Evaluation of Measurement Relative Uncertainty Using the Information Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2019年第3期486-504,共19页
The purpose of this work is to prove that only by applying a theoretically sound information approach to developing a model for measuring the Boltzmann constant, one can justify and calculate the value of the required... The purpose of this work is to prove that only by applying a theoretically sound information approach to developing a model for measuring the Boltzmann constant, one can justify and calculate the value of the required relative uncertainty. A dimensionless parameter (comparative uncertainty) was proposed as a universal metric for comparing experimental measurements of Boltzmann constant and simulated data. Examples are given of applying the proposed original method for calculating the relative uncertainty in measuring the Boltzmann constant using an acoustic gas thermometer, dielectric constant gas thermometer, Johnson noise thermometer, Doppler broadening thermometer. The proposed approach is theoretically justified and devoid of the shortcomings inherent in the CODATA concept: a statistically significant trend, a cumulative value of consensus or a statistical control. We tried to show how a mathematical-expert formalism can be replaced by a simple, theoretically grounded postulate on the use of information theory in measurements. 展开更多
关键词 boltzmann constant COMPARATIVE UNCERTAINTY Information-Based APPROACH RELATIVE UNCERTAINTY
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Boltzmann constant determined by fluorescent spectroscopy for verifying thermometers 被引量:4
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作者 Weiwei ZHANG Yiqing GAO Xingdao HE 《Frontiers of Optoelectronics》 EI CSCD 2014年第1期64-68,共5页
As is always accompanying temperature in physics fundamental principles, Boltzmann constant kB can be used to verify the accuracy of a thermometer. This paper presents a photoluminescent method to measure kB via tempe... As is always accompanying temperature in physics fundamental principles, Boltzmann constant kB can be used to verify the accuracy of a thermometer. This paper presents a photoluminescent method to measure kB via temperature dependent fluorescence of phosphors. Diagram of a phosphor's energy levels was simplified to illustrate the principle of measurement. The relationship between kB and h*c (Planck constant h multiplying light speed in vacuum c) was experimentally derived. Finally, the determined kB was 1.38065 x l0 23j/K. The determination could give a value of (1.38+0.1) × 10 23 J/K even when the in-use spectrometer was with a poor resolution as about 2 nm. At the end, optimization of measuring conditions for the determination process was suggested. 展开更多
关键词 TEMPERATURE boltzmann constant (kB) Planckconstant (h)
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Lattice Boltzmann方法模拟常速对流弥散方程 被引量:1
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作者 谈叶飞 周志芳 《水电能源科学》 2008年第1期78-80,103,共4页
在解决地下水溶质运移问题时有多种数值模拟方法,运用BGK逼近的Lattice Boltzmann模型,在结合纯弥散方程基础上推导出常速对流弥散方程(CDE)及数值解法,通过Matlab编程计算了一个用于模型检验的一维模型。计算结果显示,运用此方法得出... 在解决地下水溶质运移问题时有多种数值模拟方法,运用BGK逼近的Lattice Boltzmann模型,在结合纯弥散方程基础上推导出常速对流弥散方程(CDE)及数值解法,通过Matlab编程计算了一个用于模型检验的一维模型。计算结果显示,运用此方法得出的数值与解析值吻合良好,证明了该数学模型是正确的。 展开更多
关键词 LATTICE boltzmann模型 常速CDE 数值模拟
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How the Flat Space Cosmology Model Correlates the Recombination CMB Temperature of 3000 K with a Redshift of 1100
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作者 Eugene Terry Tatum U. V. S. Seshavatharam 《Journal of Modern Physics》 2024年第2期174-178,共5页
This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the... This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the Tatum and Seshavatharam Hubble temperature formulae can be derived using the Stephan-Boltzmann dispersion law. Thus, as explained herein, the era of high precision Planck scale quantum cosmology has arrived. 展开更多
关键词 Hubble constant Cosmic Microwave Background Quantum Cosmology Stephan-boltzmann Upsilon Coupling constant Flat Space Cosmology ΛCDM Cosmology
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The basic blocks of the universe matter: Boltzmann fundamental particle and energy quanta of dark matter and dark energy 被引量:1
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作者 Murad Shibli Sohail Anwar 《Natural Science》 2011年第9期743-749,共7页
Recent astronomical NASA observations indicates that visible matter contributes only to about 4% of the universe total energy density, meanwhile, dark matter and dark energy contributes to 26% and 70% of the universe ... Recent astronomical NASA observations indicates that visible matter contributes only to about 4% of the universe total energy density, meanwhile, dark matter and dark energy contributes to 26% and 70% of the universe total energy, respectively, with an average density close to 10–26 kg/m3. This paper proposes an equation of state of dark energy and dark matter as one unified entity. This equation is derived based on the ideal gas equation, Boltzmann constant, Einstein energy-mass principle and based on the assumption that dark energy and dark matter behave as a perfect fluid. This analysis presents what could be the most fundamental particle and quanta of dark matter and dark energy. Considering NASA’s Cosmic Microwave Background Explorer (CMB) which estimated that the sky has an average temperature close to 2.7251 Kelvin, then the equivalent mass and energy of the proposed fundamental particle is determined. It is found that this candidate particle has an equivalent mass of 4.2141 × 10–40 Kg which is equivalent to 3.7674 × 10–23 J. Surprisingly, this value has the same order of Boltzmann constant KB = 1.38 ×10–23 J/K. This candidate particle could be the most fundamental and lightest particle in Nature and serves as the basic block of matter (quarks and gluons). Moreover, assuming a uniform space dark energy/dark matter density, then the critical temperature at which the dark matter has a unity entity per volume is determined as 34.983 × 1012 K. Analytically, it proposes that at this trillion temperature scale, the dark matter particles unified into a new quark-hydron particle. Finally, tentative experimental verification can be con ducted using the Relativistic Heavy Ion Collider (RHIC). 展开更多
关键词 DARK ENERGY DARK MATTER Equation of State boltzmann constant Boltzamnn particles Einstine’s COSMOLOGICAL constant
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Quantization Heat Capacity Equations at Constant Volume According to Energy Levels and Planck Constant
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作者 Daekyoum Kim Youngpak Lee 《American Journal of Analytical Chemistry》 2018年第8期353-365,共13页
The quantization thermal excitation isotherms based on the maximum triad spin number (G) of each energy level for metal cluster were derived as a function of temperature by expanding the binomial theorems according to... The quantization thermal excitation isotherms based on the maximum triad spin number (G) of each energy level for metal cluster were derived as a function of temperature by expanding the binomial theorems according to energy levels. From them the quantized geometric mean heat capacity equations are expressed in sequence. Among them the five quantized geometric heat capacity equations, fit the best to the experimental heat capacity data of metal atoms at constant pressure. In the derivations we assume that the triad spin composed of an electron, its proton and its neutron in a metal cluster become a basic unit of thermal excitation. Boltzmann constant (kB) is found to be an average specific heat of an energy level in a metal cluster. And then the constant (kK) is found to be an average specific heat of a photon in a metal cluster. The core triad spin made of free neutrons may exist as the second one additional energy level. The energy levels are grouped according to the forms of four spins throughout two axes. Planck constant is theoretically obtained with the ratio of the internal energy of metal (U) to total isotherm number (N) through Equipartition theorem. 展开更多
关键词 Statistical Thermodynamics QUANTIZED Heat Capacity of Metal Five Energy Levels BINOMIAL Theorem boltzmann constantS PLANCK constant
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High Accuracy When Measuring Physical Constants: From the Perspective of the Information-Theoretic Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2020年第5期861-887,共27页
The practical value of high-precision models of the studied physical phenomena and technological processes is a decisive factor in science and technology. Currently, numerous methods and criteria for optimizing models... The practical value of high-precision models of the studied physical phenomena and technological processes is a decisive factor in science and technology. Currently, numerous methods and criteria for optimizing models have been proposed. However, the classification of measurement uncertainties due to the number of variables taken into account and their qualitative choice is still not given sufficient attention. The goal is to develop a new criterion suitable for any groups of experimental data obtained as a result of applying various measurement methods. Using the “information-theoretic method”, we propose two procedures for analyzing experimental results using a quantitative indicator to calculate the relative uncertainty of the measurement model, which, in turn, determines the legitimacy of the declared value of a physical constant. The presented procedure is used to analyze the results of measurements of the Boltzmann constant, Planck constant, Hubble constant and gravitational constant. 展开更多
关键词 Amount of INFORMATION CODATA boltzmann constant GRAVITATIONAL constant HUBBLE constant PLANCK constant International System of Units Mathematical Modeling Measurement Relative Uncertainty
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基于Python的PN结物理特性实验数据处理方法
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作者 李奇 马晓波 +3 位作者 曹志杰 马玲 杜全忠 撒强 《宁夏大学学报(自然科学版)》 CAS 2023年第3期272-274,281,共4页
半导体PN结物理特性实验中的数据计算量大,如果使用普通计算器计算,不仅繁琐费时而且易引入误差.通过Python语言调用Numpy模块可实现对实验数据的多项式拟合,再通过Matplotlib模块可实现可视化绘图.结果表明,该方法能快速、准确处理实... 半导体PN结物理特性实验中的数据计算量大,如果使用普通计算器计算,不仅繁琐费时而且易引入误差.通过Python语言调用Numpy模块可实现对实验数据的多项式拟合,再通过Matplotlib模块可实现可视化绘图.结果表明,该方法能快速、准确处理实验数据,给出电流电压关系拟合曲线,对PN结实验数据的分析和处理有很好的辅助作用. 展开更多
关键词 PYTHON语言 数据拟合 PN结物理特性实验 玻尔兹曼常数测定
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用电路噪声测量玻尔兹曼常量和电子电荷
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作者 宋冰睿 张立帆 +4 位作者 齐潇骏 刘佳睿 张翀玮 王中平 张增明 《物理实验》 2023年第3期43-49,共7页
设计并搭建热噪声和散粒噪声测试电路系统,利用锁相放大器,从极强的背景噪声中提取微弱待测电信号,输入参考信号实现频谱搬移测量法,测定了玻尔兹曼常量k和电子电荷e.该实验能够加深学生对电路噪声特性的理解,掌握锁相放大器技术和微弱... 设计并搭建热噪声和散粒噪声测试电路系统,利用锁相放大器,从极强的背景噪声中提取微弱待测电信号,输入参考信号实现频谱搬移测量法,测定了玻尔兹曼常量k和电子电荷e.该实验能够加深学生对电路噪声特性的理解,掌握锁相放大器技术和微弱信号测量方法. 展开更多
关键词 玻尔兹曼常量 电子电荷 频谱搬移测量法 热噪声 散粒噪声 锁相放大器 参考信号
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电阻热噪声测量玻尔兹曼常量的教学探索
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作者 李佳明 申玉宽 +2 位作者 张浩毅 王媛 何振辉 《物理实验》 2023年第8期29-35,共7页
玻尔兹曼常量是连接微观热运动与宏观物理现象和规律的重要物理量,基于电阻热噪声的玻尔兹曼常量测量实验可应用于大学物理实验教学.本文利用锁相放大器OE1022,设计了电磁屏蔽更好的样品盒,可以在室温至液氮温度间测量热噪声,托展了宽... 玻尔兹曼常量是连接微观热运动与宏观物理现象和规律的重要物理量,基于电阻热噪声的玻尔兹曼常量测量实验可应用于大学物理实验教学.本文利用锁相放大器OE1022,设计了电磁屏蔽更好的样品盒,可以在室温至液氮温度间测量热噪声,托展了宽频谱段的测量,展现电阻热噪声的特性,并计算出玻尔兹曼常量.对2个年级采用不同的实验方案进行教学,为有限课时内多人参与的实验室环境下测量玻尔兹曼常量提供教学参考. 展开更多
关键词 玻尔兹曼常量 电阻热噪声 锁相放大器 遥测
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二极管PN结的正向电流特性测量 被引量:6
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作者 马元良 李海琴 +2 位作者 毛多鹭 张以生 李仲 《物理实验》 2013年第11期4-7,共4页
使用nA级的微电流源测量了1N4148二极管的微电流伏安特性,分析了二极管PN结的扩散电流和复合电流对伏安特性的影响.通过1N4148二极管与S9014三极管等效PN结的微电流伏安特性相比较,解释了不直接用二极管测量玻尔兹曼常量的原因.
关键词 PN结 扩散电流 复合电流 玻尔兹曼常量
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常温下玻尔兹曼常数的测量 被引量:7
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作者 王吉有 王丽香 原安娟 《大学物理实验》 2006年第2期30-32,共3页
在小电流下测量了PN结的正向伏安特性,在对数坐标下,绘制了伏安特性曲线,采用线性回归方法计算了直线的斜率,计算出了玻尔兹曼常数,该值与公认值的误差仅为1.3%。此外还计算出了此温度下的反向饱和电流。
关键词 玻尔兹曼常数 反向饱和电流 PN结
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基于荧光光谱的玻尔兹曼常量测量 被引量:1
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作者 张巍巍 李珊 +3 位作者 何兴道 高益庆 陈学岗 朱泉水 《大学物理》 北大核心 2011年第10期36-38,41,共4页
玻尔兹曼常量的准确测量有助于对温度基本单位的重新定义.本文提出了一类测量玻尔兹曼常量的方法———荧光光谱方法:根据电子占据不同能级的玻尔兹曼分布规律,通过测量不同温度下荧光材料的荧光光谱,分析温度对荧光强度比例的影响,推... 玻尔兹曼常量的准确测量有助于对温度基本单位的重新定义.本文提出了一类测量玻尔兹曼常量的方法———荧光光谱方法:根据电子占据不同能级的玻尔兹曼分布规律,通过测量不同温度下荧光材料的荧光光谱,分析温度对荧光强度比例的影响,推导得到玻尔兹曼常量kB与hc(普朗克常量与真空光速的乘积)的数值关系.kB值的初步测量结果与目前CODATA推荐值(2006年)的偏差约0.2%. 展开更多
关键词 玻尔兹曼常量 温度 基本单位
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波尔兹曼常数测量及实验数据处理 被引量:5
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作者 李明标 董海宽 +1 位作者 刘长江 李波欣 《渤海大学学报(自然科学版)》 CAS 2005年第2期163-164,共2页
本文应用P-N结电压电流特性,较精确测量了玻尔兹曼常数,应用计算机进行了实验数据分析处理。实验中采用弱电流测量的方法,在其它有关弱电流测量的实验中可以借鉴。
关键词 波尔兹曼常数 PN结 弱电流测量 数据处理
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玻尔兹曼常数的Multisim仿真实验测试 被引量:4
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作者 李明标 《渤海大学学报(自然科学版)》 CAS 2017年第3期206-210,共5页
PN结正向扩散电流随正向电压按指数规律变化,这是PN结的物理特性,也是玻尔兹曼常数实验测试原理,按照FD-PN-2型PN结物理特性测定仪所给出的实验线路及元器件型号,在计算机上应用Multisim仿真软件构建虚拟仿真实验电路进行虚拟实验,给出... PN结正向扩散电流随正向电压按指数规律变化,这是PN结的物理特性,也是玻尔兹曼常数实验测试原理,按照FD-PN-2型PN结物理特性测定仪所给出的实验线路及元器件型号,在计算机上应用Multisim仿真软件构建虚拟仿真实验电路进行虚拟实验,给出了Multisim仿真实验方案及参数设置方法.在仿真实验中,通过调整可变电阻改变三极管发射结上的电压,以实现输出电压的改变.对得到的数据,用最小二乘法进行线性回归、乘幂回归和指数回归,对比标准偏差、相关系数,分析实验数据与几种函数的拟合情况,确定拟合的曲线为指数规律变化曲线,在室温条件下,计算玻尔兹曼常数的结果与公认值相当接近.该虚拟仿真实验测试电路简洁,实验过程直观明了,电压调节方便,数据计算结果较为精确,有助于学生创建良好的仿真实验环境,提升实验水平和教学效果. 展开更多
关键词 PN结 伏安特性 玻尔兹曼常数 MULTISIM 虚拟仿真 函数拟合
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利用PN结进行玻耳兹曼常数测定的实验研究 被引量:3
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作者 汪逸新 《辽宁师范大学学报(自然科学版)》 CAS 1995年第1期37-42,共6页
给出了以晶体二极管I-V特性精确测定玻耳兹曼常数的方法,修正了杨介信等所给出的测试规程和要求.
关键词 玻耳兹曼常数 载流子 半导体 PN结 二极管 测定
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基于格子玻尔兹曼方法的致密砂岩驱替模拟 被引量:3
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作者 唐明明 卢双舫 +4 位作者 辛盈 檀洪坤 刘雪萍 时贤 张洪亮 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2020年第2期10-19,共10页
基于数字岩心建模方法和格子玻尔兹曼方法,开展致密砂岩水驱模拟研究,分析致密砂岩水驱微观过程和机制。首先利用大庆油田龙虎泡地区高台子组致密砂岩CT扫描数据,建立三维数字岩心模型;然后利用Shan-Chen格子玻尔兹曼方法,建立油水两相... 基于数字岩心建模方法和格子玻尔兹曼方法,开展致密砂岩水驱模拟研究,分析致密砂岩水驱微观过程和机制。首先利用大庆油田龙虎泡地区高台子组致密砂岩CT扫描数据,建立三维数字岩心模型;然后利用Shan-Chen格子玻尔兹曼方法,建立油水两相驱替数值模型;之后对比分析不同注入速度和注入压力条件下驱替效率、换油率与驱替参数的关系,并给出致密砂岩三维微观孔隙尺度的驱替过程。结果表明:相同累积注入量条件下,提高水驱注入速度和驱替压差可以提高最终驱替效率;水驱注入速度和驱替压差存在驱替效率拐点;恒速水驱的平均最终驱替效率为49.6%,恒压水驱的平均最终驱替效率为47.3%。 展开更多
关键词 致密砂岩 格子玻尔兹曼方法 恒压驱替 恒速驱替 数字岩心
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基于芯片级控温技术的玻尔兹曼常量测定仪 被引量:1
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作者 宋建平 苟刚 +1 位作者 朱太宜 姜哲 《物理实验》 北大核心 2011年第12期11-14,23,共5页
为解决测量玻尔兹曼常量时获取PN结真实温度及温度连续变化的问题,设计了基于芯片级控温技术的玻尔兹曼常量测定仪.该仪器采用以AVR单片机为核心控制系统,集成电路CA3046为控温芯片,24064图形点阵液晶显示器作为显示单元.将加热电阻和... 为解决测量玻尔兹曼常量时获取PN结真实温度及温度连续变化的问题,设计了基于芯片级控温技术的玻尔兹曼常量测定仪.该仪器采用以AVR单片机为核心控制系统,集成电路CA3046为控温芯片,24064图形点阵液晶显示器作为显示单元.将加热电阻和测温传感器与PN结集成在同一芯片内组成PN组件.单片机对PN组件进行温度控制,可以实现对PN组件中PN结温度调整、恒温控制、温度测量并用液晶屏24064显示.实际应用表明,该测定仪具有升降温快、控温稳定,测量结果与国际公认值相对偏差小于2%. 展开更多
关键词 玻尔兹曼常量 PN结 芯片控温 单片机
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利用晶体三极管测玻尔兹曼常量实验方法的讨论 被引量:3
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作者 杨德甫 杨能勋 《物理实验》 2008年第10期30-32,共3页
在不使用运算放大器的情况下,直接利用晶体三极管与数字式电流表测出扩散电流,可以得到较为准确的玻尔兹曼常量.
关键词 晶体三极管 玻尔兹曼常量 PN结 扩散电流
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