Radiation Energy Research Articles

Recent advances in vanadium dioxide for dynamic thermal radiation modulation: A review

Thermal radiation of materials can be manipulated for the necessary applications in thermal management and infrared camouflage. To our knowledge, controlling surface emissivity is crucial for modulating thermal radiative energy, therefore, dynamic modulation of emissivity has received more attention. Vanadium dioxide (VO2) stands out as a highly promising candidate due to its capacity for reversible transition from monoclinic VO2(M) to rutile VO2(R) near room temperature. This transition results in a rapid change from transparent to opaque within the mid-infrared spectrum accompanied by a reduction in emissivity. This review offers an overview of recent progresses in the dynamic control of thermal radiation of the surface by using VO2. It also summarizes the preparation, modulation mechanisms, and applications of positive and negative differential emissivity devices. Finally, the challenges and opportunities in advancing research on VO2-based smart devices are discussed.

Analysis of chemical characteristics of engine‐oil‐based Prandtl hybrid nanofluid flow

AbstractThe literature showed that an empirical experiment creates another part of exploration that has been made in the field of thermal science, such that today, modern researchers are more directed to utilize hybrid types of nanoparticles due to their efficient thermal conductivity compared to single nanoparticles. The study of the hybrid flow of nanofluid is essential in many scientific and industrial arguments, such as power generation, medical equipment, oil refineries, and so forth. Furthermore, it has distinctive features to advance the expertise of their energy sources and cooling methodologies. Incentives by this research postulation: The significant objective of this investigation is to design a mathematical model of Prandtl hybrid nano liquid flow over a Riga plate when nanoparticles of aluminum alloys (AA7072 and AA7075) are suspended in engine oil. Mixed convection, activation energy, and heat radiation are also considered. The nanomaterial is modeled using a modified Buongiorno model that considers the functional qualities of hybrid nanofluids. The simulated PDEs are converted into a collection of nonlinear ODEs with appropriate and relevant similarity transformations, which are numerically addressed using finite‐difference‐oriented bvp4c procedure in MATLAB. Graphs and tables are used to evaluate and show the impacts of different factors on velocity, temperature, concentration fields, skin friction number, and Nusselt number. The velocity profile develops with the enhancement of Prandtl fluid parameters. With the increment in the magnetic parameter, both temperature and concentration profiles improve, but in the case of the Brownian motion parameter, the concentration profile declines. In terms of heat transfer, hybrid nanofluids outperform ordinary nanofluids. The current results provide an equitable contrast against the results that already exist.

C─H Activation Enables the Construction of New Bis-Polyaryl Phenylpyridine Ruthenium Complexes: Conjugation and Rigidity Synergistic Effect for Advanced Electrochemiluminescence.

The access to bench-stable organometallic compounds unfolds new chemical space for medicinal and material sciences. In particular, stable organoruthenium compounds with constitutional and stereoisomeric forms for subtle regulation of electrochemiluminescence are intriguing and challenging. Here, coordination of polycyclic aromatic hydrocarbons on (2-phenylpyridine)2(CO)2Ru complex allows access to bis-polyaryl phenylpyridine (BPP) Ruthenium complex through C─H activation strategy and coupling reactions for installation of the functionalities with steric and electronic purposes. The photoluminescence and electrochemiluminescence of BPP Ru complexes are affected by the actual polycyclic aromatic hydrocarbons inherent properties. The anthracene derivatized BPP Ru complex (BPP-Ant) shows the best ECL performance and reveals an enormous ECL quantum efficiency of 1.6-fold higher than the golden standard Ru(bpy)3 2+. The unprecedentedly high efficiency is due to the best compromise between the structural conjugation and molecular rigidity from BPP-Ant providing a providential energy gap that facilitated the feasibility of electron transfer and favored the radiative energy release by experimentally and DFT calculations. Moreover, PL and spooling ECL spectroscopies are used to track and link multiple emission peaks of BPP-Ant at 445, 645, and 845nm to different emissive species. These discoveries will add a new member to the efficient ECL ruthenium complex family and bring more potentials.

Radioluminescence Dosimetry in Modern Radiation Therapy

Accurate and precise measurement of radiation energy delivered to and absorbed by the patient's tissue is of great importance in radiation therapy (RT) quality assurance. Radioluminescence (RL) dosimetry has shown great potential for high spatiotemporal resolution dose measurement of RT fields. Implementation of efficient RL dosimetry in RT requires multidisciplinary effort and skills in optics, medical physics, radiation physics, electronics, and imaging science. In this review, a wide overview of fundamentals and applications of RL properties of media for RT dosimetry with emphasis on their potential use for multidimensional, small‐field, and ultra‐high dose rate RT dosimetry is provided.

Exploring structural and optical properties of Cu-doped and Fe-doped sodium borate glasses

This study investigated the structural and optical properties of Cu-doped and Fe-doped sodium borate glasses. X-ray diffraction (XRD) patterns confirmed that both samples were amorphous, with no sharp peaks. However, differences in the width and center of the high-intensity humps suggested variations in atomic packing and field strength between the two samples. Fourier transform infrared (FTIR) spectra showed wider vibrational modes and stronger absorption in the Fe-doped sample, confirming its higher atomic packing and field strength. Luminescence spectra indicated that the Cu-doped sample had a higher ratio of Cu2+:Cu3+ than the Fe-doped sample of Fe2+:Fe3+, resulting in greater UV–visible region absorption. Optical parameters such as absorbance, transmittance, and reflectance supported these findings, with the Fe-doped sample exhibiting higher absorbance band edges. Quality factor (Q.F.) analysis revealed that the Fe-doped sample had a larger Q.F. than the Cu-doped sample, indicating lower energy losses. Furthermore, the optical conductivity of both samples increased with photon energy, with the Cu-doped sample dominating in all energy regions. Finally, both samples exhibited high effective atomic numbers, suggesting potential applications in radiation shielding, with the Cu-doped sample having a wider radiation shielding window. Finally, the findings unique structural and optical properties suggests the Cu-doped and Fe-doped sodium borate glasses to a lot of potential applications in various fields including radiation shielding, optics, electronics, and energy storage.

Circular orbits and accretion disk around AdS black holes surrounded by dark fluid with Chaplygin-like equation of state

In the present work we study the geodesic motion and accretion process of a test particle near an Anti-de Sitter (ADS) BH surrounded by a dark fluid with a Chaplygin-like equation. Within the defined paradigm, we investigate on the equatorial plane and examine circular geodesics along with their features related to stabilities, radiation energy flux, oscillations and orbits. The general form of the fluid accretion onto the AdS BH through dynamical analysis and mass expansion also has discussed in a depth. Additionally, a few more interesting topics, e.g. the effective potential, angular momentum, specific energy, radiation energy and epicyclic frequencies have also been examined thoroughly. All the attributes are physically acceptable within the observational signatures and ranges.

Bound state in the continuum and polarization-insensitive electric mirror in a low-contrast metasurface.

High-contrast refractive indices are pivotal in dielectric metasurfaces for inducing various exotic phenomena, such as the bound state in the continuum (BIC) and electric mirror (EM). However, the limitations of high-index materials are adverse to practical applications, thus, low-contrast metasurfaces offering comparable performance are highly desired. Here, we present a low-contrast dielectric metasurface composed of radial anisotropic cylinders, which are SiO2 cylinders doped with a small amount of WS2. The cylinder exhibits unidirectional forward superscattering resulting from the overlap of the electric and magnetic dipole resonances. When a near-infrared plane wave incident normally, the metasurface consisting of the superscattering constituents manifests a polarization-insensitive EM. In contrast, when subjected to an in-plane incoming wave, the metasurface generates a symmetry-protected BIC characterized by an ultrahigh Q factor and nearly negligible out-of-plane energy radiation. Notably, the EM response of the metasurface exhibits robustness to deviation in the number and thickness of WS2 layers. Our work highlights the doping approach as an efficient strategy for designing low-contrast functional metasurfaces, thereby shedding new light on the potential applications in photonic integrated circuits and on-chip optical communication.

Advancing Cloud Classification Over the Tibetan Plateau: A New Algorithm Reveals Seasonal and Diurnal Variations

AbstractThe cloud classification algorithm widely used in the International Satellite Cloud Climatology Project (ISCCP) tends to underestimate low clouds over the Tibetan Plateau (TP), often mistaking water clouds for high‐level clouds. To address this issue, we propose a new algorithm based on cloud‐top temperature and optical thickness, which we apply to TP using Advanced Himawari Imager (AHI) geostationary satellite data. Compared with Clouds and the Earth's Radiant Energy System cloud‐type products and ISCCP results obtained from AHI data, this new algorithm markedly improved low‐cloud detection accuracy and better aligned with cloud phase results. Validation with lidar cloud‐type products further confirmed the superiority of this new algorithm. Diurnal cloud variations over the TP show morning dominance shifting to afternoon high clouds and evening mid‐level clouds. Winter is dominated by high clouds, summer by mid‐level clouds, spring by daytime low clouds and nighttime high clouds, and autumn by low and mid‐level clouds.

Investigation of Dust‐Induced Direct Radiative Forcing Over the Arabian Peninsula Based on High‐Resolution WRF‐Chem Simulations

AbstractThis study investigates the impact of dust on radiation over the Arabian Peninsula (AP) during the reported high, low, and normal dust seasons (March–August) of 2012, 2014, and 2015, respectively. Simulations were performed using the Weather Research and Forecasting model coupled to a Chemistry module (WRF‐Chem). The simulated seasonal horizontal and vertical dust concentrations, and their interannual distinctions, match well with those from two ground‐based AERONET observations, and measurements from MODIS and CALIOP satellites. The maximum dust concentrations over the dust‐source regions in the southern AP reach vertically upto 700 hPa during the high dust season, but only upto 900–950 hPa during the low/normal dust seasons. Stronger incoming low‐level winds along the southern Red Sea and those from Iraq bring in higher‐than‐normal dust during the high dust summers. We conducted a sensitivity experiment by switching‐off the dust module to assess the radiative perturbations due to dust. The results suggest that active dust‐module improved the fidelity of simulated radiation fluxes distributions at the surface and top of the atmosphere vis‐à‐vis Clouds and the Earth's Radiant Energy System (CERES) measurements. Dust results in a 26 Wm−2 short‐wave (SW) radiative forcing in the tropospheric‐column over the AP. The SW radiative forcing increases by another 6–8 Wm−2 during the high dust season due to the increased number of extreme dust days, which also amplifies atmospheric heating. During extreme dust days, the heating rate exhibits a dipolar structure, with cooling over the Iraq region and warming of 40%–60% over the southern‐AP.

Examining Sustainable Urban Design Pattern by Explaining the Compatibility Model based on Density in Residential Fabrics of District 4th in Tehran City

Concerns about energy and climate change have taken center stage in urban studies in recent years. Buildings are the primary focus of the problem of maximizing energy efficiency in cities, and among the energy Additionally, the most crucial aspects of urban energy efficiency research are consumption, solar radiation energy on the one hand, and thermal energy demand on the other. These factors, together with other climatic factors, primarily influence the standard of life in urban areas. The main aim of research is to establish a model of sustainability in the physical form of the city, the primary objective of the current research is to extract the ideal framework and also the proposed model in the form of a structure for the concept of urban design in urban morphology, which is, on the one hand, the architectural scale of the buildings of the urban fabrics. In terms of structure, the current research is analytical-descriptive, and the method of data collection is in the form of documentation, survey, modeling and simulation using energy analysis software in the field of energy with a micro-analytical approach of urban climate such as Envi-met. For this reason, 4 morpho-types were evaluated in the context of the 4th district of Tehran, and the findings of the research show the difference between the optimal state and the current state of the evaluated parameters, and the amount of difference and the effect of added density in each morphological type of the effective range based on the index It explains that the high-rise building type has the most positive changes in the proposed conditions, and the compact types have lower values respectively. In the future researches, other morphological variables and adaptation modes with climatic parameters can also be investigated in order to achieve energy efficiency in other modes. DOI: https://doi.org/10.52783/pst.545

Computational Fluid Dynamics Analysis of Temperature Distribution in Solar Distillation Panel with Various Flat Plate Materials

As the world population continues to grow, the demand for clean water is increasing daily, making it a crucial resource to access. However, there are ways to harness abundant resources like solar energy and seawater to produce clean water. The present studies have conducted experimental investigations to convert seawater into freshwater using solar stills, where solar energy is utilized as the primary heat source for evaporation. The temperature distribution inside the solar stills was analyzed using a flat plate made of three different materials: copper, stainless steel, and aluminum. To examine the temperature distribution and performance of the solar stills, researchers employed computational fluid dynamics simulations (Ansys R15.0). The results showed variations in temperature distribution among the three plate materials. Copper flat plates achieved the highest temperature, approximately 44.5 Celsius, followed by aluminum at 43.91 Celsius, while stainless steel exhibited the lowest temperature at around 42.01 Celsius. The average heat flux across the three materials was approximately 581 W/m2. Additionally, observations indicated that the amount of convection occurring in copper flat plates was 121.108 Watts; in aluminum, it was 118.517 Watts; and in stainless steel, it was 105.05 Watts. The radiation energy for stainless steel flat plates was 29.93 W; for copper, 16.14 W; and for aluminum, 13.49 W.

Identification method of the hydrodynamic and acoustic natures of wall pressure fluctuation based on dynamic mode decomposition

In this study, an analysis method is proposed to explain the dynamic mode decomposition (DMD) mode of wall fluctuating pressure from the perspective of hydrodynamics and acoustics. According to the phase velocity, the wavenumber–frequency spectrum is divided into hydrodynamic, acoustic, and subconvective regions. Multiple DMD modes of the pressure field are calculated to obtain the wavenumber–frequency spectrum of the reconstructed pressure, which is characterized by the fact that the energy is concentrated at different wavenumber positions of the same frequency. This behavioral feature enables the DMD mode to be identified as a hydrodynamic, acoustic, and hybrid property according to the wavenumber position where the energy spot appears. This method can realize the classification and contribution analysis of the hydrodynamic and acoustic properties of the wall pressure DMD mode, and establish the mapping relationship between the acoustic mode and the eddy current characteristics through the eigenvalues. The coherent structure of the trace acoustic energy radiation in the incompressible fluid is observed from the statistical perspective, which increases understanding of the flow noise. The zero-pressure gradient wall flow experiment of Abraham is numerically analyzed using the aforementioned method. The results indicate that most of the DMD modes are identified as hydrodynamic, and only the nineteenth-order DMD mode is identified as acoustic. The frequency of the acoustic mode is 23.9 Hz, which has obvious wave-packet characteristics, whereas the hydrodynamic mode exhibits nonradiative convection characteristics, and its eddy current structure is closer to the wall transfer.

Numerical Simulation of Bioconvection Maxwell Nanofluid Flow due to Stretching/Shrinking Cylinder with Gyrotactic Motile Microorganisms: A Biofuel Applications

The bioconvection effects with nanofluid are major application in biofuels. This analysis aimed to observe the bioconvection effect in unsteady two-dimensional Maxwell nanofluid flow containing gyrotactic motile microorganisms across a stretching/shrinking cylinder evaluating the consequences of thermal radiation and activation energy. The Cattaneo-Christov double diffusion theory is also observed. Nanofluids are quickly perceptive into many solicitations in the latest technology. The current research has noteworthy implementations in the modern nanotechnology, microelectronics, nano-biopolymer field, biomedicine, biotechnology, treatment of cancer therapy, cooling of atomic reactors, fuel cells, and power generation. By using the proper similarity transformation, the partial differential equations that serve as the basis for the current study are gradually reduced to a set of highly nonlinear forms of ordinary differential equations, which are then numerically, approached using a well-known shooting scheme and the bvp4c tool of the MATLAB software. Investigated is the profile behavior of the flow regulating parameters for the velocity field, thermal field, and volumetric concentration of nanoparticles and microorganisms. From the results, it is concluded that velocity is reduced with a larger bioconvection Rayleigh number. The thermal field is increased with a larger amount of thermal Biot number and thermal radiation. The concentration of nanoparticles increases with an increment in the thermophoresis parameter. Furthermore, the microorganism’s field is decreased with a larger Lewis number. The findings demonstrate that by optimizing the concentration of nanoparticles and microorganisms, the thermal efficiency of biofuels can be significantly improved. This leads to more sustainable and efficient energy production. By optimizing the concentration of nanoparticles and microorganisms in biofuels, the thermal properties can be significantly improved, leading to more efficient combustion processes. This can reduce the overall cost and increase the yield of biofuels. Improved cooling systems for medical imaging devices such as MRI machines can be developed using nanofluids, ensuring better performance and patient safety.

Mathematical analysis of heat and mass transfer efficiency of bioconvective Casson nanofluid flow through conical gap among the rotating surfaces under the influences of thermal radiation and activation energy

In the current proceeding, the flow of incompressible non-Newtonian nanofluid called Casson nanofluid is considered. A conical gap occurred among the rotating disc and the cone filled with the fluid flow. Heat and mass transport through this nanofluid is done by the convection mode of heat transfer. The impacts of microorganisms, chemical processes, thermal radiation, minimal amount of energy, and magnetic field are also considered in the mathematical model of flow problem. The Casson nano-fluid governing equations are interpreted in cylindrical coordinates. By implementing proper similarity transformations, the modeling PDEs of energy, momentum, concentration, and microorganism density are transformed into non-linear ODEs. A set of non-linear ODEs that deals with the distributions of temperature, velocity, concentration, and motile microorganisms produced by this technique. MATLAB in-built ‘bvp4c‘ technique is utilized to solve these equations. Findings are displayed graphically and elaborated theoretically. The primary goal of this work is to examine the effects during the rotation of the disc and cone as well as the impacts of other variables on the rotation. The nano-fluid temperature and radial velocity are found to be negatively impacted by the rotation parameter whereas azimuthal velocity is positively impacted. The parametric values are taken as 0.1<Nb<0.7, 0.1<λ<0.4, 1.0<Pr<2.50.1<M<0.4, 1.0<Rb<4.0, 0.1<Nr<0.4, 0.1<Sc<3.0, 0.1<Nt<0.4 for the purpose of generating modified results. From published and current results noted that rotation parameter effects impacted the transfer rate of the nanofluid.

A high performance solar-assisted ejector expansion refrigeration cycle for residential air conditioning

Introducing a solar collector between the compressor and condenser of an ejector expansion refrigeration cycle (EErc) can improve the performance of the system by further superheating the refrigerant. Hence, this paper proposes a new configuration of a vapor compression refrigeration system, solar compression-ejector expansion refrigeration cycle (SCEErc) with energy saving in the compressor via an ejector and an evacuated tube solar collector. The performance improvement of the proposed system under a wide range of operating conditions such as condenser and evaporator temperatures, superheating and subcooling degrees, nozzle and diffuser efficiencies, and solar radiation intensities has been evaluated and compared with EErc under the same operational conditions and for four different refrigerants. The results indicate that the coefficient of performance (COP) of the SCEErc increased by 26.53 % compared to the EErc for the solar radiation energy of 0.2 kW. Moreover, exergy analysis results indicate a 59 % increase in the exergy destruction of the condenser in the SCEErc compared to the EErc. This is due to the increase in heat rejected from the condenser to the environment, which can be beneficial if the condenser cooling air outlet is utilized for applications like heat recovery technologies. The R152a, boasting a COP of 3.963, presents itself as a more favorable alternative to R134a.

Accretion disks properties around regular black hole solutions obtained from non-linear electrodynamics

We investigate a family of spherically symmetric, static, charged regular black hole solutions derived within the framework of Einstein-nonlinear electrodynamics. Our study focuses on examining the characteristics of accretion disks in the spacetimes described by the Dymnikova and Fan-Wang solutions. We explore circular geodesics of test particles and calculate various properties, including the radius of the innermost stable circular orbit, radiant energy, temperature, and conversion efficiency of accretion mass into radiation. We employ the Novikov-Thorne-Page thin accretion disk model as a background. By comparing our findings with those obtained in the Schwarzschild black hole case, we reveal significant modifications in the overall spectral properties. Specifically, we observe an increase in the energy emitted from the disk surface, resulting in higher temperatures for the accretion disks under certain values of the free parameters. Consequently, we note an enhanced efficiency of mass conversion into radiation compared to the Schwarzschild spacetime.

The possibility of using the DKS-AT1123 dosimeter for radiation monitoring of medical electron accelerators with the energy of more than 10 MeV

In the Russian Federation, there is a constant increase in the number of radiation medical installations with electron accelerators. Over the past 4 years, their number has increased 2.5 times. These installations contain pulsed electron accelerators that generate pulsed bremsstrahlung radiation with a maximum energy from 6 to 21 MeV. Currently, there are no devices designed for dosimetry of the pulsed photon radiation with energy of more than 10 MeV in the state register of measuring instruments of the Russian Federation. The most widely used radiation monitoring device for pulsed electron accelerators is the DKS-AT1123 X-ray and gamma radiation dosimeter designed for dosimetry of pulsed bremsstrahlung radiation with an energy of up to 10 MeV. The purpose of this work is to evaluate the possibility of using this device for dosimetry of pulsed bremsstrahlung radiation with a maximum energy of up to 20 MeV. The authors calculated the energy spectra of bremsstrahlung radiation for a point source with a maximum energy of 20 MeV behind flat concrete screens with a thickness of 1 m, 2 m and 3 m by the Monte Carlo method using the GEANT4 calculation program. The energy dependence of the registration efficiency of the DKS-AT1123 dosimeter was extrapolated to the energy range of 10–50 MeV in the kerma-approximation without taking into account the energy transfer by secondary electrons. It was assumed that it corresponds to the energy dependence of the total mass attenuation coefficient for the absorbed energy of gamma quanta in water. Using conversion coefficients for converting the fluence of monoenergetic photons into the effective dose rate at an anterior-posterior radiation incidence on the human body, real dose rates were calculated, and using the energy dependence of the dosimeter readings, the predicted results of measuring the unit dose rate with the DKS-AT1123 dosimeter behind a concrete protection with a thickness of 1, 2 and 3 m were obtained. It is shown that the maximum expected underestimation of the measurement results will not exceed 40% and practically does not depend on the thickness of the concrete shield in the thickness range from 1 to 3 m. To account for this underestimation, it is necessary to use the value of additional measurement error due to the energy dependence of the sensitivity of this device for the photon radiation energy of more than 10 MeV, equal to 70%. This makes it possible to use the measurement results obtained using this dosimeter to adequately characterize the state of radiation safety during operation of pulsed electron accelerators with a maximum energy of up to 20 MeV. It is possible to use a correction factor to the measurement results equal to 1.63 ±0.04 to compensate for this underestimation. The proposed approach can be used to create a methodology for using this dosimeter for radiation monitoring of medical electron accelerators with the energy of up to 20 MeV, if there are correction factors for radiation protection configurations and radiation energies encountered in practice.

Clothing color effect as a target of the smallest scale climate change adaptation.

The purpose of this study is to understand a physical mechanism to determine the surface temperature of clothes in calm and fine conditions of outdoors. We observed surface temperatures of polo shirts of the same material and design but different colors. The shirts were placed in unshaded and well-ventilated outdoor, open spaces on sunny summer days. The maximum difference between dark green or black and white was more than 15°C during calm, fine weather and was greatest when the solar radiation was strong. If the transmission of solar radiation energy through a shirt is ignored to calculate the absorption by the shirt, the difference in solar radiation absorption due to different colors is as much as 24% in the maximum, and if considered, we concluded that an absorption difference of 34% led to a temperature difference of 15℃. When we compared the brightness of the colors, we found that the albedo of both the visible and NIR bands explained why the red and green colors were so different with respect to the surface temperatures we observed. The reflection in the NIR bands was also an important determinant of the surface temperature. An additional experiment using masks showed that the temperature difference between white and black was almost eliminated at a wind speed of ~ 3m/s. The color of clothing is therefore a target for small-scale adaptation to climate change.

Assessment of temperature distribution on inclined porous rod with a convective and insulated tip

The following work focuses on determining the temperature profile of porous rod using radiative and insulated tip conditions. In addition, graphs are generated to investigate the impact of several non-dimensional attributes on the distribution of temperature for various modes of energy exchange, such as boiling of nucleates and radiative energy exchange, including the convection-conduction parameter, permeability parameter, and radiation-conduction parameter. ND solve technique is applied to solve the generated nonlinear partial differential equation by using MATHEMATICA. The transient thermal response has been visually presented for various key parameters with ranges p=0,2, Nr=1,5,10, Nc=0.3,0.4,0.5, Pe=0.1,0.2,0.3, Q=0.1,0.2,0.3, Bi=1,2,3. The graphical outcome reveals that temperature distribution is a decreasing function of radiation parameter. Exposure time of the rod to the environment gets short for the enhancement in Peclet number. Initially temperature contours are linear, as time progresses the exponential behavior is developed.

Radiation Dose Units: How We Got Here, Do They Serve the Purposes They are Intended to?

The current radiation dose estimates used in medical imaging, radiation oncology or environmental assessments are not entirely accurate from a fundamental physics perspective, let alone for biological consequences. The "one cloth fits all" approach of radiation-matter interactions cannot assess the effects of interactions of the same species of radiation of different energies on the same isotope of an element. Preliminary steps to set the radiation dosimetry in the right direction are suggested.