Physical Decomposition Research Articles

Research on indoor air pollutant control technology and data analysis

This study provides a comprehensive analysis of indoor air pollutant control technologies and reports on the current status of indoor air pollution and its hazards to human health in China. This research also emphasizes the biological mechanisms through which indoor air pollutants affect human health at the cellular and molecular levels. The study explores the mechanisms, kinetics, thermodynamics, and material design and performance optimization of various control methods, including physical adsorption, chemical decomposition, and biological purification. A detailed discussion is included on how indoor air pollutants interact with biological systems, focusing on mechanistic pathways such as oxidative stress, inflammatory responses, and cellular signaling alterations induced by exposure to pollutants. Data analysis reveals the removal efficiencies and application effects of different technologies, highlighting the biological impacts of these pollutants on human health. It was concluded that in the future, emphasis should be placed on the research and development of efficient and low-cost adsorbent materials, the optimization of the chemical decomposition method in order to reduce energy consumption and extend the catalyst life, the in-depth study of biological purification methods in order to screen highly efficient degrading microorganisms. Additionally, a combined approach utilizing various technologies is recommended to achieve comprehensive treatment of indoor air pollutants, thereby mitigating their harmful effects on biological systems.

Physical decomposition stage and ergosterol content predict the chemical composition of downed dead wood in Mediterranean dehesas

AbstractDead wood is a key substrate of forests that plays an important role in fertility and productivity. However, dead wood is scarce in traditionally managed forests like Mediterranean dehesas. The chemical composition of downed dead wood in Quercus pyrenaica dehesas was analysed in different physical decomposition stages as a proxy of dead wood decay length. We also assessed the contribution of fungal activity, by quantifying ergosterol, to the chemical composition of deadwood. Chemical analyses included elemental composition determination, thermogravimetry and infrared spectroscopy. Our results showed that both the physical decomposition stage and ergosterol content extensively predicted the chemical composition of Q. pyrenaica dead wood decay processes under field conditions. The physical stage was a better predictor of the C/P ratio and polysaccharides proportion, while ergosterol better predicted P content and the N/P ratio. In other cases like lignin, the relation between ergosterol content and chemical composition varied depending on the physical stage. In addition, environmental local factors differentially affected chemical composition across physical decomposition stages. We conclude that the physical decomposition stage and ergosterol content complementarily contribute to estimate the temporal behaviour of the chemical composition of dead wood in Mediterranean areas. Moreover, we recommend using the FT-IR analysis to assess the nature of temporal chemical changes in downed dead wood. Finally, our study claims to consider the potential impact of local environmental factors, such as air temperature and relative humidity, on dead wood decay processes in traditionally managed forests in the current global change scenario.

Mechanical traits as drivers of trophic interaction between macrodetritivores and leaf litter.

In ecosystems, the rates of resource consumption by animals drive the flows of matter and energy. Consumption rates are known to vary according to consumer energy requirements, resource nutrient content and mechanical properties. The aim of our study is to determine how mechanical constraints, compared to energetic and nutritional constraints, explain the variation in leaf litter consumption rates by macrodetritivores. In particular, we focus on the impact of litter toughness. To this end, we propose a non-linear model describing leaf litter consumption rates of detritivore as a function of litter toughness. We also investigate a possible match between bite force and litter toughness, since consumer-resource co-occurrence is thought to be driven by the match between invertebrate mandibular traits and resource toughness. Our study was designed as follows: leaf litter from oak and hornbeam was exposed to field physical and microbial decomposition in aquatic and terrestrial ecosystems for selected time periods before it was offered to eight macrodetritivore taxa (three forest stream taxa and five forest soil taxa) in no-choice laboratory feeding experiments. Our findings show that, compared to energetic and nutritional constraints, mechanical traits have a greater impact on litter consumption rate by detritivores. After subtracting the contribution of the detritivore body mass, we report that litter consumption rates depend primarily on litter toughness. A sigmoid function is best suited to characterize the relationship between mass-independent consumption rate and litter toughness. We note that the parameters of our sigmoid model are taxon-specific, suggesting biomechanical thresholds and biological differences among taxa. Interestingly, we found no correlation with detritivore bite force, suggesting that food processing by detritivores does not only depend on mandibles strength.

The effect of citric acid concentrations on the mechanical, thermal, and structural properties of starch edible films

SummaryThis study investigated the effects of citric acid on the properties of edible tapioca starch films plasticised with glycerol. These films were formed using 5% tapioca (w/w of water); 1%, 3%, 5%, 7% and 9% citric acid (w/w of starch); and 2.2% glycerol (w/w of water). Native starch films formed using 5% tapioca and 2.2% glycerol were used as the control. The properties tested included the degree of crosslinking, thermal stability, crystallinity and mechanical properties. These were evaluated using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR‐FTIR), X‐Ray diffraction (XRD), thermal gravimetric analysis (TGA) and tensile profile analysis (TPA). The FTIR results provided information about the nature of the crosslinking in the films, while TGA showed that increasing the citric acid concentration reduced the physical decomposition temperature of the materials. Films containing 9% citric acid had the highest degree of esterification and crosslinking, while those containing 7% citric acid had the lowest heat‐related weight loss that correlated with the degree of crosslinking. The weight loss among all six samples was the greatest in the temperature range 260 °C–350 °C where a total of 60% weight loss occurred. The XRD results showed that films containing 3% citric acid had the lowest crystallinity while the native starch films had the highest crystallinity. The TPA analyses showed that films containing 5% citric acid had the greatest influence on improving the tensile strength and elastic modulus, while also having the best impact on lowering the elongation. Tensile strength values recorded for films containing 0%, 1%, 3%, 5%, 7% and 9% citric acid were 5.327, 7.813, 8.688, 12.855, 14.549 and 11.614 MPa. Similarly, when citric acid concentration increased from 3% to 5%, the elastic modulus significantly increased from 831.058 to 2255.691 MPa. This study demonstrated that the physicochemical properties of tapioca starch‐based films could be modified by the incorporation of citric acid.

Uncovering the decomposition mechanism of nitrate ester plasticized polyether (NEPE): a neural network potential simulation.

Nitrate ester plasticized polyether (NEPE) propellants have attracted widespread attention due to their high energy density and excellent low-temperature mechanical properties. However, little is known about the thermal decomposition process of the NEPE propellant, particularly lacking microscale models and interaction mechanisms. This work aims to establish a high-precision and efficient neural network potential (NNP) model covering the NEPE matrix, describing its mechanical behavior and detailed thermal decomposition mechanisms. The model accuracy, including atomic energies and forces, was validated through density functional theory (DFT) results, and the NEPE propellant decomposition model was verified via molecular dynamics (MD) simulations with DFT precision. The results demonstrate that the NNP model accurately predicts the energies and forces of the NEPE matrix for single and mixed systems at the DFT-level precision, and reproduces the mechanical properties consistent with DFT calculations. Meanwhile, the thermal decomposition order of the NEPE matrix predicted by NNP is consistent with the experimental results, accurately capturing complex physical phenomena and detailed decomposition processes among components. It is also revealed that the addition of a binder can improve the stability of the propellant and extend its energy release time. This study applies innovative machine learning algorithms to develop an NNP computational model for the NEPE matrix with DFT precision, which is crucial for practical propellant formulation design.

“Knitted” tetrabenzo-24-crown-8 ether sulfonate as reusable and practical hydrophilic adsorbent for aqueous Cs+ sequestration

Herein, “knitted” tetrabenzo-24-crown-8 ether sulfonate (X-S-TB24CE8) was prepared to afford a practical hydrophilic Cs+ adsorbent. Cyclic TB24CE8 ligands were hyper-crosslinked with dimethoxymethane in the presence of Cs+ template followed by sulfonation to introduce -SO3- groups. Thorough characterization of X-S-TB24CE8 using FTIR, TGA, EA, N2 adsorption/desorption, DLS, XPS, and SEM-EDX confirms its hydrophilic nature and thermal stability. It possesses a granulated porous structure that can be easily recovered by filtration. Removal of Cs+ by X-S-TB24CE8 involves a 1:1:2 TB24CE8:Cs+:SO3- coordination with additional Cs+···SO3- interaction from free sulfonate groups. The Cs+ adsorption follows the Sips isotherm model (Qmax = 233.07 mg g−1) and pseudo-second order kinetics (k2 = 2.63 × 10−3 g mg−1 min−1). In seawater containing Cs+, X-S-TB24CE8 exhibits a strong preference for Cs+ over Na+ (αNa+Cs+= 483), K+ (αK+Cs+= 76), Mg2+ (αMg2+Cs+= 66), and Ca2+ (αCa2+Cs+= 35). X-S-TB24CE8 demonstrated consistent adsorption/desorption performance without undergoing any physical or chemical decomposition. These findings indicate that X-S-TB24CE8 holds significant potential as a competitive and practical adsorbent for Cs+ sequestration.

Morphological, physical, chemical, and thermal decomposition properties of air-heat-treated balsa fruit fibers at different temperatures

Morphological, physical, chemical, and thermal decomposition properties of air-heat-treated balsa fruit fibers at different temperatures

Unsupervised video rain streaks removal with deep foreground–background modeling

Outdoor video rain streaks removal is an important inverse problem in video processing that benefits subsequent applications. Traditional methods utilize prior information with interpretable domain knowledge while they are not tenable to capture complex structures of real-world videos. Deep learning methods learn a deraining mapping with a large model capacity brought by deep neural networks and their performances highly depend on the volume and diversity of training data. To address the challenging video deraining problem, we suggest an unsupervised video rain streaks removal method by solely using the observed rainy video. For the complex clean video, inspired by the classical foreground–background decomposition, we employ a deep convolutional neural network to capture the moving foreground and a disentangled deep spatial–temporal network with an affine operator to capture the underlying low-rank structure of the dynamic background. The foreground and background components are well balanced by a learnable probability mask. For structured rain streaks, we introduce a learnable total variation regularization whose parameters (i.e., rain directions) can be unsupervisedly learned. The deep modeling of the complex clean video and the simple yet effective modeling of structured rain streaks under the physical interpretable decomposition framework, which benefit each other in nature, are organically integrated to boost the deraining performance. Extensive experiments on synthetic and real-world rainy videos demonstrate the superiority of our method over state-of-the-art traditional and deep learning-based video deraining methods.

Changes in global food consumption increase GHG emissions despite efficiency gains along global supply chains.

Greenhouse gas (GHG) emissions related to food consumption complement production-based or territorial accounts by capturing carbon leaked through trade. Here we evaluate global consumption-based food emissions between 2000 and 2019 and underlying drivers using a physical trade flow approach and structural decomposition analysis. In 2019, emissions throughout global food supply chains reached 30 ±9% of anthropogenic GHG emissions, largely triggered by beef and dairy consumption in rapidly developing countries-while per capita emissions in developed countries with a high percentage of animal-based food declined. Emissions outsourced through international food trade dominated by beef and oil crops increased by ~1 Gt CO2 equivalent, mainly driven by increased imports by developing countries. Population growth and per capita demand increase were key drivers to the global emissions increase (+30% and +19%, respectively) while decreasing emissions intensity from land-use activities was the major factor to offset emissions growth (-39%). Climate change mitigation may depend on incentivizing consumer and producer choices to reduce emissions-intensive food products.

Efficient recycling of carbon fiber from carbon fiber reinforced composite and reuse as high performance electromagnetic shielding materials with superior mechanical strength

Carbon fiber reinforced boron phenolic resin composite (CF/BPR) is widely used. However, it is hard to decompose its waste for highly cross-linked networks. Herein, a solvothermal decomposition route was proposed to decompose CF/BPR and recycle carbon fibers. Decomposition ratio of resin (Dr) reached 99.78%. Possible decomposition mechanism was proposed based on characterizations of decomposition products. Composite was decomposed for synergistic effects of physical swelling, mechanical impact and chemical decomposition. Surface morphology and microstructure characterization of recycled carbon fibers (RCFs) confirmed that resin was highly removed while no significant harm was caused to RCFs. It was found that RCFs reinforced boron phenolic resin composite (RCFs/BPR) had superior punch type shear strength due to improved wettability and interfaces. Moreover, RCFs/BPR exhibited superior electromagnetic shielding performance in X-band frequency for improved conductive network. This work presents a facile and efficient pathway for decomposing composite waste and reuse as high performance electromagnetic shielding materials.

Mechanism analysis on the mitigation of harbor resonance by periodic undulating topography

Gao et al. (2021. Investigation on the effects of Bragg reflection on harbor oscillations. Coastal Engineering, 170: 103977) attempted to utilize Bragg reflection to alleviate harbor resonance, and discovered its significant effectiveness for the first time. The Bragg reflection occurred over periodic topographies deployed outside and parallel to the harbor entrance. However, the inherent mitigating mechanisms were not revealed. In this paper, the Bragg reflection over a patch of sinusoidal bars and its coupling effects with the harbor are studied using a Boussinesq-type model. Different from the previous study, the sinusoidal bars with various numbers and amplitudes are arranged in the manner of an arc layout around rather than parallel to the entrance. A physical process decomposition method is proposed to reveal the inherent mitigation mechanism. Moreover, the condition under which harbor resonance is not excited by incident waves (hereinafter referred to as "harbor non-resonance condition") is also investigated, and the similarities/differences of mitigation mechanisms between the harbor resonance and non-resonance conditions are discussed. Finally, for the harbor resonance condition, the effects of the number and the amplitude of sinusoidal bars on the best mitigation effect and optimal bar wavelength, which can attain the best mitigation effect, are systematically analyzed.

Large anomalies in future extreme precipitation sensitivity driven by atmospheric dynamics

Increasing atmospheric moisture content is expected to intensify precipitation extremes under climate warming. However, extreme precipitation sensitivity (EPS) to temperature is complicated by the presence of reduced or hook-shaped scaling, and the underlying physical mechanisms remain unclear. Here, by using atmospheric reanalysis and climate model projections, we propose a physical decomposition of EPS into thermodynamic and dynamic components (i.e., the effects of atmospheric moisture and vertical ascent velocity) at a global scale in both historical and future climates. Unlike previous expectations, we find that thermodynamics do not always contribute to precipitation intensification, with the lapse rate effect and the pressure component partly offsetting positive EPS. Large anomalies in future EPS projections (with lower and upper quartiles of −1.9%/°C and 8.0%/°C) are caused by changes in updraft strength (i.e., the dynamic component), with a contrast of positive anomalies over oceans and negative anomalies over land areas. These findings reveal counteracting effects of atmospheric thermodynamics and dynamics on EPS, and underscore the importance of understanding precipitation extremes by decomposing thermodynamic effects into more detailed terms.

Review of Emission Characteristics and Purification Methods of Volatile Organic Compounds (VOCs) in Cooking Oil Fume

Volatile organic compounds (VOCs) in cooking oil fumes need to be efficiently removed due to the significant damage they cause to the environment and human health. This review discusses the emission characteristics, which are influenced by different cooking temperatures, cooking oils, and cuisines. Then, various cooking oil fume purification methods are mainly classified into physical capture, chemical decomposition, and combination methods. VOCs removal rate, system operability, secondary pollution, application area, and cost are compared. The catalytic combustion method was found to have the advantages of high VOC removal efficiency, environmental protection, and low cost. Therefore, the last part of this review focuses on the research progress of the catalytic combustion method and summarizes its mechanisms and catalysts. The Marse-van Krevelen (MVK), Langmuir-Hinshelwood (L-H), and Eley-Rideal (E-R) mechanisms are analyzed. Noble metal and non-noble metal catalysts are commonly used. The former showed excellent activity at low temperatures due to its strong adsorption and electron transfer abilities, but the high price limits its application. The transition metals primarily comprise the latter, including single metal and composite metal catalysts. Compared to single metal catalysts, the interaction between metals in composite metal catalysts can further enhance the catalytic performance.

A design framework for a system of digital twins and services

Digital twins represent physical systems in virtual space to enable knowledge intensive tasks. For complex physical systems, effective digital integration can often be achieved by means of a system of aggregated digital twins coupled with a services network. Designing such a system of digital twins and services involves a daunting array of options and considerations. This paper presents a design framework that facilitates systematic, effective decisions when designing a system of digital twins to integrate the data from a complex physical system. The design framework is arranged in six steps: 1) needs and constraints analysis, 2) physical system decomposition, 3) services allocation, 4) performance and quality considerations, 5) implementation considerations and 6) verification and validation. The design framework works with a general reference architecture that combines a digital twin aggregation hierarchy with a service-oriented architecture. This reference architecture allows for the separation of concerns, computational load distribution, incremental development and modular software design. The paper considers the merits of the design framework using two illustrative case studies, i.e. a heliostat field and a smart city. The case studies indicate that the design framework can be applied to a wide range of complex systems and can improve the effectiveness of the design process.

Degradation kinetics of rutin encapsulated in oil-in-water emulsions: impact of particle size.

Rutin is a natural bioactive flavonoid that is poor in water solubility and chemical stability. Encapsulation can be used to protect bioactive molecules from chemical or physical decomposition during food processing and storage. Thus, the effect of initial particle size on the ability of oil-in-water emulsions to retain rutin during storage was investigated. Rutin was encapsulated in oil-in-water emulsions with different mean surface-weighted diameters: d3,2 =0.56 μm (small), 0.73 μm (medium), and 2.32 μm (large). As expected, the resistance of the emulsions to coalescence and creaming during storage increased as the particle size decreased due to weakening of the colloidal and gravitational forces acting on the droplets. The concentration of rutin in the emulsions decreased during storage (28 days), which was mainly attributed to photodegradation of the flavonoid. The loss of rutin from the emulsions during storage was fitted using a second-order equation. The rutin degradation rate constant k decreased and the half-life t1/2 increased with decreasing droplet size, which was attributed to the stronger encapsulation and light scattering by smaller oil droplets reducing the amount of light that can penetrate into the emulsions. This study has important implications for the design of more efficacious emulsion-based delivery systems for incorporating health-promoting nutraceuticals into foods. © 2022 Society of Chemical Industry.

Extraction of cellulose nanocrystals from red banana peduncle agro‐waste and application in environmentally friendly biocomposite film

AbstractThe agricultural waste dumped onto the land is creating an environmental problem. The conversion of those easily available agro‐wastes into value‐added nano reinforcement materials for biopolymers is an alternative method of waste utilization and minimization. In the current study, the red banana peduncle (RBP) waste was used as a precursor in the extraction of carboxylated cellulose nanocrystals (CCNCs) by alkalization, acidified chlorination citric acid hydrolysis, as well as the assessment of its reinforcing capability in polyvinyl alcohol. The characterization of the extracted CCNCs is analyzed through electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), and Thermogravimetric analysis (TGA), respectively. The CCNCs exhibit a rod‐like shape (235 ± 20 nm length and 17.2 ± 6 nm width) with a high crystallinity of 89.7%, a negative zeta potential (−48 mV), and good thermal resistivity against degradation up to 280 °C. Furthermore, the effects of CCNCs integration on the bionanocomposite films' tensile, optical, bio decomposition, and thermal behavior were examined. The bionanocomposite film with improved physical, functional, thermal and bio decomposition characteristics offers the possibility for active packaging applications.

Comprehensive performance of multifunctional lightweight composite reinforced with integrated preform for thermal protection system exposed to extreme environment

The novel multifunctional lightweight composites (MLCs) reinforced with integrated preform were prepared for thermal protection system (TPS) of hypersonic vehicles in extreme aerothermodynamic environment. The high-temperature behavior including thermal physical properties decomposition performance, and the ablation resistance were tested by the oxy-acetylene torch system, as well as the micro-morphologies of MLCs from non-destructive testing were investigated. An integration factor was proposed to evaluate the comprehensive performance of MLCs. The results show that MLCs had high structural efficiency without delamination and defelting, excellent thermal insulation performance, and superior ablation resistance ability. The comprehensive performance of MLCs had obvious advantages to polymer-matrix composites (PMCs). The novel MLC reinforced with integrated preform can help for the development of thermal protection materials of hypersonic aircrafts.

Chemical composition and bioactive compounds of cashew (Anacardium occidentale) apple juice and bagasse from Colombian varieties

Cashew nut production generates large amounts of cashew apple as residue. In Colombia, cashew cultivation is increasing together with the concerns on residue management. The objective of this study was to provide the first chemical, physical and thermal decomposition characterization of cashew apple from Colombian varieties harvested in Vichada, Colombia. This characterization was focused to identify the important bioactive and natural compounds that can be further valorized in the formulation of food, nutraceuticals, and pharmacological products. The results obtained in this study are helpful to portray the cashew apple as a potential by-product due to its renewable nature and valuable composition, instead of seeing it just as an agricultural residue. For that, cashew apples of Regional 8315 and Mapiria varieties were studied. The natural juice (cashew apple juice) that was extracted from the cashew apples and the remanent solids (cashew apple bagasse) were separately analyzed. The HPLC analytical technique was used to determine the concentration of bioactive compounds, structural carbohydrates, and soluble sugars that constitute this biomass. Spectrophotometric techniques were used to determine the concentration of tannins, carotenoids, and total polyphenols. Mineral content and antioxidant activity (DPPH and ABTS assays) were determined in the biomass. Also, the thermal decomposition under an inert atmosphere or pyrolysis was performed on cashew apple bagasse. The varieties of cashew apple studied in this work showed similar content of bioactive compounds, total phenolic content, and structural carbohydrates. However, the Mapiria variety showed values slightly higher than the Regional 8315. Regarding cashew apple juice, it is rich in tannins and ascorbic acid with values of 191 mg/100 mL and 70 mg/100 mL, respectively, for Mapiria variety. Additionally, the principal reservoir of bioactive compounds and constitutive carbohydrates was the cashew apple bagasse. About 50 wt.% of it was composed of cellulose and hemicellulose. Also, in the bagasse, the ascorbic acid content was in a range of 180–200 mg/100 g, which is higher than other fruits and vegetables. Moreover, alkaloids were identified in cashew apples. The maximum value of antioxidant activity (DPPH assay: 405 TEs/g) was observed in the bagasse of Mapiria variety. The bagasse thermal decomposition started around 150 °C when the structural carbohydrates and other constitutive substances started to degrade. After thermogravimetric analysis, a remanent of 20% of the initial weight suggested the formation of a rich-carbon solid, which could correspond to biochar. Therefore, the cashew apple harvested in Vichada is a valuable reservoir of a wide range of biomolecules that potentially could be valorized into energy, foods, and pharmacologic applications. Nevertheless, future work is necessary to describe the complex compounds of this residual biomass that are still unknown.

ProFuse: physical multiband structural decomposition of galaxies and the mass–size–age plane

ABSTRACT We present the new ProFuse r package, a simultaneous spectral (ultraviolet to far-infrared) and spatial structural decomposition tool that produces physical models of galaxies and their components. This combines the functionality of the recently released ProFound (for automatic source extraction), ProFit (for extended source profiling), and ProSpect (for stellar population modelling) software packages. The key novelty of ProFuse is that it generates images using a self-consistent model for the star formation and metallicity history of the bulge and disc separately, and uses target images across a range of wavelengths to define the model likelihood and optimize our physical galaxy reconstruction. The first part of the paper explores the ProFuse approach in detail, and compares results to published structural and stellar population properties. The latter part of the paper applies ProFuse to 6664 z < 0.06 GAMA galaxies. Using re-processed ugriZYJHKs imaging we extract structural and stellar population properties for bulges and discs in parallel. As well as producing true stellar mass based mass–size relationships, we further extend this correlation to explore the third dimensions of age and gas phase metallicity. The discs in particular demonstrate strong co-dependency between mass–size–age in a well-defined plane, where at a given disc stellar mass younger discs tend to be larger. These findings are in broad agreement with work at higher redshift, suggesting discs that formed earlier are physically smaller.

An investigation of the Helmholtz and wave-vortex decompositions on surface currents in a coastal region

Recent efforts to observe sea surface height (SSH) fields at less than kilometer spatial resolution using various satellite missions have spurred interest in understanding how well balanced and unbalanced motions can describe the ocean surface current field at finer scales, particularly in coastal regions characterized by complex flows under multiple driving forces (e.g., tides, winds, and low-frequency signals). In this study, we investigated the Helmholtz physical decomposition and wave-vortex decomposition to delineate the balanced and unbalanced motions of coastal surface currents while considering their reasonable justifications individually. The observed and simulated coastal surface currents do not exhibit an evident decomposition of balanced and unbalanced motions when wave-vortex decomposition is applied. Wave-vortex decomposition may not always be valid in coastal regions in which (1) the isotropy, spatial homogeneity, temporal stationarity, and statistical zero-correlations of the current components may not be guaranteed, and (2) multiple geophysical signals and footprints of driving forces are present. In contrast, the stream function obtained from the Helmholtz physical decomposition can be used as a proxy for balanced motions when the variance of vertical currents is weak, except for near-inertial variance. We believe that the Helmholtz decomposition in the physical domain will provide better insights into the dynamical decomposition than that in the spectral domain and can be applied to the analysis of upper ocean dynamics, including the propagation of unbalanced motions and vertical and horizontal structures of ageostrophic currents. Based on our study, SSH fields that will be observed at a very high spatial resolution in upcoming satellite missions will complement ocean current fields at finer scales, particularly in coastal regions characterized by a complex flow geometry.