Concentration Distribution Research Articles

Detection of Factors Affecting the Spatial Distribution of Ozone in Summer over China Based on Geodetector

To study the factors affecting the spatial distribution of ozone concentration in different regions of China, based on the summer ozone monitoring data of 2019 and three influencing factors, namely, main meteorological, direct emission, and socio-economic factors, the influence degree of various factors on the spatial differentiation of ozone was quantified by using the Geodetector method and the comparison between regions was conducted. The results showed that the spatial differentiation of ozone concentration in summer 2019 was most affected by the main meteorological factors and the average degree of influence reached 0.277. Relative humidity was the dominant meteorological factor and the influence degree reached 0.415. The degree of influence of meteorological factors increased from northeast and western regions to central regions. The influence of social and economic factors increased from north to south, except for the low plateau climate area. The analysis on the interaction of two factors revealed that the average wind speed of meteorological factors had the greatest impact on other factors and large regional differences were present. Among socio-economic factors, population density had the greatest impact on other factors and was the key factor driving the regional differentiation of other factors. These results are helpful to understand the dominant factors of spatial distribution of ozone concentration in different regions of China and have guiding importance for the prevention and control of ozone pollution.

Slippage flow of second-grade fluid over a vertical plate with thermo-diffusion effect: an application of hybrid fractional operator

This research investigates the effects of slip and thermo-diffusion on magnetohydrodynamic fluid flow and heat transfer through a porous medium, using a fractional second-grade fluid model. A semi-analytical solution is obtained through Laplace transform techniques, revealing detailed insights into concentration, temperature, and velocity distributions. The study sheds light on the significant impact of key parameters, including Prandtl and Schmidt numbers, Grashof numbers, and the second-grade parameter, on the intricate relationships between thermo-diffusion, slip conditions, and fluid flow in porous media.

Unraveling the variability and geoclimatic drivers of daily precipitation concentration over a Western Himalayan Province of India.

A sound understanding of daily precipitation concentration provides critical insights about extreme precipitation and associated hazards such as rainstorms, flash floods, cloud bursts, and soil erosion. Therefore, this study examines the spatiotemporal variability and geoclimatic drivers of daily precipitation concentration using the concentration index (CI), precipitation concentration degree (PCD), Q Index (QI), and Theil index (TI) over a Western Himalayan Province, namely Himachal Pradesh, India. For this, the daily precipitation data pertaining to 111 grids (0.25° × 0.25° resolution), encompassing entire province, have been downloaded from India Meteorological Department (IMD), Pune, for the period 1951 to 2020. The trends in concentration indices have been detected using Mann-Kendall (MK) and Sen's slope methods, whereas their relationship with geoclimatic drivers have been assessed using Pearson's correlation coefficient (physiographic) and random forest regression model (climatic) at annual and monsoon season time scales. The results have revealed a high correlation between CI-TI (> 0.95), followed by QI-TI (> 0.84), QI-PCD (> 0.80), TI-PCD (> 0.78), QI-CI (> 0.65), and CI-PCD (> 0.60), representing nearly similar precipitation concentration distribution. Among the concentration indices, QI has shown maximum sensitivity to long-term changes followed by TI, CI, and PCD at both time scales. Similarly, physiographic factors have maximum effect on QI, showing its greatest sensitivity to latitude, longitude and elevation. While considering the impact of climatic drivers, Atlantic Meridian Oscillation (AMO) and Sunspot activity have exerted maximum influence on annual variability of CI, PCD, QI, and TI, whereas monsoon variability of these indices has been modulated by Pacific Decadal Oscillation (PDO), especially over northern parts of Himachal Pradesh. These findings will assist soil and water resource managers, disaster executives, agricultural stakeholders, and urban planners in understanding the unexplored aspects of daily precipitation concentration and making informed decisions over the mountainous regions of western Himalaya.

Simulation study on hydrogen concentration distribution in hydrogen blended natural gas transportation pipeline.

Hydrogen is a clean energy source, and blending it with natural gas in existing pipeline networks is a key transition solution for transportation cost reduction. However, during the transportation process, a non-uniform distribution of hydrogen concentration occurs in the pipeline due to gravity. Therefore, it is necessary to study the hydrogen concentration distribution law of hydrogen-blended natural gas in pipelines. The undulation and ball valve pipelines, which are common in transport pipelines, were constructed in this study. The effects of the undulation angle, height, pipeline diameter, ball valve opening, and temperature on the distribution of the hydrogen concentration were investigated using computational fluid dynamic (CFD) methods. The results indicated that the hydrogen concentration gradient changed gently with the larger diameter of the undulating pipeline, minimizing hydrogen accumulation. Higher undulation angle and smaller height differences reduces the hydrogen accumulation risk. Increasing vertical height difference of the pipeline from 5 m to 15 m increased the hydrogen volume fraction gradient by1.3 times. In the ball valve pipeline, the velocity fluctuation decreased as the ball valve opening increased. However, the hydrogen accumulation phenomenon was obvious. The opening increased from 25% to 100% and the hydrogen volume fraction gradient increased more than two times. Selecting delivery conditions with low hydrogen blending ratios, high temperatures, low pressures, and high flow rates reduces the occurrence of hydrogen buildup in the pipeline.

Formation and snake-eating like solubilization mechanisms of rhamnolipid vesicles for oil components and amino acids

Rhamnolipid vesicles hold significant potential across a wide range of applications, yet their formation mechanisms and selective solubilization of organic molecules remain elusive. Employing dissipative particle dynamics (DPD) simulations, this study delves deeply into these aspects, uncovering a stepwise formation pathway from dispersed monomers to complex multi-layer vesicle structures. The fusion and growth of three-layer structures were identified as crucial steps in the development of stacked vesicles. Notably, double-chain rhamnolipids (Rh-C10-C10) exhibited enhanced stability in self-assembled structures compared to their single-chain counterparts (Rh-C10). Through a detailed analysis of parameters such as relative concentration distribution, radial distribution function, and density fields, the solubilization process of rhamnolipid vesicles was found to resemble a “snake-eating” mechanism. We also analyzed the solubilization sites, amounts, and vesicle sizes, elucidating the selective solubilization mechanisms of rhamnolipids for representative polar and non-polar compounds in crude oil, anisole and 1-hexene. The selectivity of rhamnolipid vesicles in solubilizing organic molecules was primarily influenced by polar attraction and steric hindrance, which together determined their solubilization sites within the vesicles. Additionally, the solubilization behavior and properties of five types of amino acids within rhamnolipid vesicles were explored, demonstrating analogous solubilization patterns that correlated with amino acid polarity. These results provide a foundation for optimizing the application of rhamnolipid vesicles, paving the way for potential advancements in drug delivery, environmental remediation, and oil recovery processes.

A spatio-temporal assessment of seawater quality in Miri-Sibuti Coral Reef: Evaluating for metal pollution, sources and dynamics

Coral environments are sensitive to seawater quality, and their sustenance depends on understanding the dynamics of geochemical variables, especially in trace levels. Miri-Sibuti Coral Reef National Park (MSCRNP) is a unique marine reserve in the state of Sarawak, NW Borneo, Malaysia, which attracts tourists worldwide. In this study, seawater samples were collected from MSCRNP in three different diving sites (Eve’s Garden (EG), Anemone Garden (AG) and North Siwa (NS)) at different depths for three seasons (pre-southwest monsoon (PRSWM), post-southwest monsoon (POSWM) and northeast monsoon (NEM). Insitu parameters (temperature, pH, salinity and turbidity) were measured in the field. The concentration of trace metals was determined in the water column (sea surface layer, middle layer and bottom water) using standard procedure. Statistics and pollution indices were used to identify the possible sources of metals and the pollution status of the seawater. From the analytical results, the vertical distribution of trace metal concentrations with respect to the locations and seasons was identified. pH ranging from 7.8 to 8.4 with a depth-wise increasing trend in NS during NEM. Similarly, a decreasing trend of turbidity was observed in AG and EG in all the seasons with respect to depth. A higher concentration of trace metals was observed during NEM, particularly at EG and NS. Fe, Ni and Pb are the dominant metals in all the seasons. Fe concentration varies from 789 to 1,478µg/L, averaging 1,112µg/L irrespective of seasons and locations. The suspended solids/sediments discharged by the river runoff were the main contributor to the distribution of metals. The release of metals from the suspended particles through desorption at the surface layers and the exchange of metals between water-sediment interface at the bottom water were observed. In addition, coastal development and other anthropogenic activities in this region were also contributed to the metal pollution.

Phase equilibrium and separation process of byproduct vinyl acrylate in the ethylene vapor phase method producing vinyl acetate

Vinyl acrylate is one of the byproducts in the ethylene vapor phase method for the production of vinyl acetate (VAc), which not only has a toxic effect on the catalyst but also affects the purity of the product. Currently, phase equilibrium data for vinyl acrylate with water are missing, making the destination of vinyl acrylate in the distillation process uncertain. This has led to a lack of effective removal means, which restricts the optimization of the ethylene vapor phase method. This paper uses a method combining quantum chemistry and molecular dynamics simulation (MD) to investigate the existential form of the water molecule. And based on the ab initio calculation of the first principle, the force field parameters of the special water molecular structure are calculated, and the TIP4P-P force field that can describe the special water structure is established. Using the Gibbs Ensemble Monte Carlo (GEMC) method, the reliability of the improved water molecule force field for modeling the phase equilibrium of a binary system is first verified. Further, vapor–liquid phase equilibrium data for the vinyl acrylate-water binary system at 110 kPa and 150 kPa are calculated and the corresponding x-y and T-x-y phase diagrams are plotted. After performing the thermodynamic consistency test, the phase equilibrium data are fitted to obtain the binary interaction parameters of vinyl acrylate with water. The fitted parameters are applied to the process simulation of the VAc refining process to optimize the conditions and obtain an effective separation scheme for vinyl acrylate. The concentration distribution of vinyl acrylate in the distillation column is investigated, thus clarifying the destination of vinyl acrylate in the distillation process and facilitating the optimization of the ethylene vapor phase method.

Microscopic insights into UiO-66@proton exchange composite membrane by molecular dynamics simulation

UiO-66 as one of the known metal-organic frameworks (MOFs) has been recognized as highly promising dopants for enhancing the proton conductivity of proton exchange membrane (PEM) owing to the large pore volume and structure tunability. Despite the numerous experimental reports on MOF-doped PEMs, their increased proton conductivity is commonly ascribed to enhanced water uptake. The underlying mechanisms from a microscopic perspective remain elusive. Therefore, this work explores the microstructure and water diffusion dynamics within composite membranes to decipher their mechanisms involved in proton conductivity using molecular dynamics (MD) simulations. Four types of composite membranes based on two representative MOFs i.e. UiO-66 and UiO-66-NH2 and two PEMs including Nafion and Dow, respectively, were taken into account. It is revealed that the UiO-66-NH2 doped Nafion composite membrane exhibits the highest water uptake among the four composite membranes resulting from the super hydrophilicity of UiO-66-NH2. Besides, the more concentrated distribution of sulfonic groups near the water-PEM interface and the higher interface roughness of UiO-66-NH2 doped Nafion lead to more water molecules surrounding its sulfonic groups that are favorable for the proton dissociation from sulfonic groups. Furthermore, the increased water channel connectivity of MOF-doped membranes that promotes proton transport through water via the Grotthuss mechanism demonstrates one of the mechanisms for increased proton conductivity. On the other hand, although the reduced lifetime of the hydrogen bond network and the enhanced water diffusion coefficient within MOF-doped membranes manifest the favorable proton transfer via the Vehicle mechanism. Overall, UiO-66-NH2 doped Nafion membranes exhibiting the highest water channel connectivity and water diffusion coefficients demonstrate the greatest potential of UiO-66-NH2 doping in advancing the proton conductivity. These findings provided microscopic insights into understanding the improved proton conductivity mechanism of MOF doped PEMs, and the approaches developed in this work may be extended to other composite membranes.

Spatial–Temporal Differentiation and Driving Factors of Vegetation Landscape Pattern in Beijing–Tianjin–Hebei Region Based on the ESTARFM Model

Urbanization and industrialization have led to obvious changes in the ecological environment and landscape pattern in the Beijing–Tianjin–Hebei region. Therefore, it is crucial to clarify the spatial–temporal changes in vegetation cover and its landscape pattern and conduct its analysis with the driving factors for ecological preservation in the Beijing–Tianjin–Hebei region. This study combined AVHRR GIMMS NDVI and MODIS NDVI data based on the ESTARFM model to obtain a high spatial–temporal resolution for vegetation cover; it then analyzed the vegetation cover changes at the type and landscape scales using a landscape index and explored the driving factors of the landscape pattern through principal component analysis. The results show that (1) the vegetation is mainly of medium and higher coverage and is distributed in the northeast, the western part of the Taihang Mountains and the central plains in the study area. From 1985 to 2022, there was no statistically significant difference in the overall change in its coverage. (2) From 1985 to 2022, at the landscape level, the vegetation cover landscape exhibited the following characteristics: increased fragmentation, an increase in the complexity of the landscape shape, a decrease in connectivity, a discrete landscape and a decrease in species diversity. At the type level, the medium vegetation demonstrated the most significant degree of fragmentation. The high-vegetation-cover areas exhibited a more concentrated distribution. Additionally, the low, lower and higher vegetation types displayed an increase in complexity, shape, discreteness and heterogeneity within the landscape. (3) Meanwhile, the principal component analysis showed that the changes in the landscape pattern of vegetation cover were mainly the result of the combined effects of climatic and anthropogenic factors in the Beijing–Tianjin–Hebei region. The human factor played the dominant role; this was followed by larger contributions from climatic factors. In addition to offering pertinent scientific insights for the maximization of the ecological environment and the fostering of regional ecological and sustainable development in the Beijing–Tianjin–Hebei region, the aforementioned analysis and research could serve as the foundation for the sustainable management and planning of vegetation cover.

Outlining the impact of electro-osmotic force and mixed convection flow of EMHD nanofluid flow on the stretched cylinder: a computational layout

Abstract This research has focused on studying the electro-magneto-hydrodynamic (EMHD) nanofluid flow over a stretched cylinder in the presence of electro-osmotic force and mixed convection. This inquiry shows a novel approach through the use of thermophoresis and Brownian motion and nanofluid is comprised of water and copper nanoparticles. Similarity transformations simplified the mathematical model and produced nonlinear ordinary differential equations with suitable boundary conditions, which the MAPLE-21 software numerically solved using the RK-4 shooting criteria. Tables and graphs have been used to illustrate the impact of the key flow factors on Electric potential profiles, velocity profiles, temperature outlines, and concentration distribution. Following the physical deliveries, we have calculated the Sherwood number, Nusselt number, and skin friction. The electro-osmotic parameter diminishes the electric potential profiles and a dual effect occurs for the curvature parameter. The Nusselt number declined by 5.91 % for the electro-osmotic parameter but the Sherwood number enhanced by 30.7 % at a rate. The practical applications of this model shed light on thermal management in electronics and nuclear reactors, plasma physics, various chemical processes, filtration, separation, and fuel cells, as well as the manipulation of biological fluids in lubrication or medical devices.

Operational Strategy of Nonuniform Air Supply in Cleanrooms

To ensure that cleanroom cleanliness requirements are met, the current design and operation of cleanrooms generally necessitate the fan filter unit (FFU) to open. However, deploying an excessive number of FFUs may lead to an air volume redundancy problem, which can reduce air volume. Conversely, reducing FFUs and their airflow might also increase the risk of uneven indoor airflow distribution and particle concentration. This study analyzes the influence of the nonuniform operational strategy of FFUs (including the opening rate, arrangement position, and air velocity of FFUs) on the distribution of airborne particulate matter concentration in the cleanroom using CFD simulation technology. Results showed that opening only the top part of the source FFU can significantly reduce the indoor particulate concentration in the cleanroom and maintain the cleanliness that meets the requirements of cleanrooms. In the case of the same number of air exchanges, increasing the air velocity of the upper FFU of the indoor airborne particulate pollution source has a significant effect on the purification of indoor particulate matter in the cleanroom. These results show that the nonuniform air supply from the upper FFU of the source has good purification performance for airborne particles in a typical cleanroom.

Multi-Scenario Simulation of Optimal Landscape Pattern Configuration in Saline Soil Areas of Western Jilin Province, China

The Songnen Plain is a significant region in China, known for its high grain production and concentrated distribution of soda saline land. It is also considered a priority area for cropland development in the country. However, the Songnen Plain is now facing prominent issues such as soil salinization, soil erosion, and deteriorating cropland quality, which are exacerbated by climate change and intensified human activities. In order to address these challenges, it is crucial to adjust the quantitative structure and layout of different landscapes in a harmonious manner, aiming to achieve synergistic optimization, which is posed as the key scientific approach to guide comprehensive renovation policies, improve saline–alkaline land conditions, and promote sustainable agricultural development. In this study, four scenarios including natural development, priority food production (PFP), ecological security priority (ESP), and economic–ecological-balanced saline soil improvement were set up based on Nondominated Sorting Genetic Algorithm II (NSGA-II) and the Future Land Use Simulation (FLUS) model. The results demonstrated that the SSI scenario, which focused on economic–ecological equilibrium, displayed the most rational quantitative structure and spatial layout of landscape types, with total benefits surpassing those of the other scenarios. Notably, this scenario involved converting unused land into saline cropland and transforming saline cropland into normal cropland, thereby increasing the amount of high-quality cropland and potential cropland while enhancing the habitat quality of the region. Consequently, the conflict between food production and ecological environmental protection was effectively mitigated. Furthermore, the SSI scenario facilitated the establishment of a robust ecological security and protection barrier, offering valuable insights for land use planning and ecological security pattern construction in the Songnen Plain, particularly in salt-affected areas.

Mapping the exposure to outdoor radon in the German population

IntroductionData on outdoor radon are generally scarce compared to indoor radon. However, knowledge of the spatial distribution of outdoor radon is necessary to estimate the overall exposure of the population to radon, it supports the prediction of indoor radon and characterizes the natural radon background. Germany has a comprehensive dataset on long-term outdoor radon concentration and the equilibrium factor at national level, which allowed to produce what is probably the only spatially continuous outdoor radon map at national level so far. DataIn this study, outdoor radon concentration measurement data (n = 172) and equilibrium factors (n = 25) from a national survey from 2003 to 2006 were reanalyzed using state-of-the-art machine learning routines. Spatially comprehensive maps of distance to the sea, radon concentration in soil, sand content in topsoil and a terrain-based wind exposure index are used as predictors. MethodsQuantile regression forest was used to map the conditional distribution of outdoor radon concentration at 500 m grid resolution. The equilibrium factor was mapped using a linear regression model. Both maps were combined to derive the equivalent outdoor radon equilibrium concentration. Population weighting of the results was achieved by explicitly accounting for the population distribution using a probabilistic sampling procedure from the estimated conditional distributions. ResultsThe arithmetic mean and the interquartile range (25th to 75th percentile) for the population-weighted outdoor radon concentration for Germany are 9.3 Bq/m³ and 5.8 Bq/m³ to 11.2 Bq/m³, respectively. The mean equilibrium factor is 0.49. The arithmetic mean and the interquartile range (25th to 75th percentile) for the population-weighted outdoor radon equilibrium equivalent concentration are 4.7 Bq/m³ and 2.7 Bq/m³ to 5.9 Bq/m³ respectively. The estimated inhalation dose due to outdoor exposure to radon is 0.056 mSv/a (arithmetic mean), with less than 10 % of the population exceeding a value of 0.1 mSv/a. The unavoidable inhalation dose due to radon exposure (outdoors plus indoors) in Germany is estimated at an arithmetic mean of 0.37 mSv/a. The spatial distribution of radon outdoors is mainly determined by the distance to the sea. The predictors radon concentration in soil, sand in topsoil and wind exposure still have a significant influence, especially at local to regional level. ConclusionKnowledge about the spatial distribution of outdoor radon and its local variability for Germany was improved using a modern regression technique and relevant predictive information. The results confirm a low outdoor radon concentration with a small contribution to the effective dose received by the population from outdoor radon exposure.

Dissolved Ba as discriminator between two adjacent karst catchments that are both subject to allogenic recharge (Sohodol Valley, Vâlcan Mountains, Romania)

In a fluviokarst region, three rarely used natural tracers, SiO2, Na and Ba, were considered for tracking the allogenic, silicate-derived water contribution to cave streams and to final karst outflows. The concerned allogenic recharge originates in watersheds that consist of metamorphic formations intruded by magmatic rocks, for which available whole rock chemistry data indicate rather uniform contents of SiO2 and Na but contrasting (up to one order of magnitude) contents of Ba. All three considered natural tracers proved to behave conservatively along karst flow-paths and indicated binary mixing between allogenic and autogenic inputs. However, only the dissolved Ba concentrations enabled chemical distinction between two adjacent karst catchments: one with allogenic inputs presumably derived mainly from the weathering of Ba-rich rocks (essentially granites), and the other with allogenic recharge originating mostly from the weathering of Ba-poor formations. In contrast, if only the SiO2 and Na concentrations of the sampled waters had been considered, it would have been virtually impossible to establish whether the two adjacent karst catchments were distinct - or not - from each other. When considering each of the two karst catchments separately, the concentrations distribution of each of the three natural tracers, SiO2, Na and Ba, consistently indicated that between a swallet and a connected cave stream, then further between cave streams and final karst outflows, the allogenic water relative contribution gradually diminished to the benefit of autogenic water.

A coupled model of zebra mussels and chlorine in collective pressurized irrigation networks

Zebra mussel infestation has become a serious problem affecting pressurized networks. Larvae settle in pipeline walls creating relevant obstructions to flow as they grow and develop shells. Oxidant injections in the stream are commonly used to control the infestation. A model is proposed for simulating the transportation, settlement and death of mussels in pressurized networks. This model is coupled to a solute transport, diffusion, and decay model of oxidant chemicals. During the analyzed irrigation campaigns, the larvae entry was monitored at various intervals. These data, showing high variability, were used as input to the model using different scenarios averaging and modifying the time distribution of larvae concentration. Simulations predicted similar mussel settlement patterns across all scenarios, suggesting that network morphology and total larval abundance primarily influence settlement distribution. We compared the effectiveness of continuous and intermittent oxidant applications. Continuous treatments were the most effective (up to 99%), but required up to 3.5 kg ha−1 of chlorine. Reasonable control could also be attained with short injections (1 to 3 h) just before the peak irrigation service discharge, leading to up to 93% of chlorine savings and reaching similar mortality rates. The model was also used to estimate the larvae and chlorine export to on-farm irrigation systems through hydrants and to evaluate strategies for mitigating the risks of on-farm infestation and environmental impact. The protection of on-farm irrigation systems required additional chlorine input. The model can be parametrized to simulate similar species in different types of pressurized networks, using different chemicals for treatment.

Study on the effects of stroke ratio, velocity ratio, and duty cycle on the diffusion characteristics of pulsed buoyant jets in crossflow

Pulsed buoyancy jet diffusion dilution is characterized by low cost and high efficiency, so it is widely used in wastewater discharge dilution projects. This study, based on three-dimensional numerical simulations, investigates the effects of stroke ratio (1.71 ≤ L/D ≤ 8.57), velocity ratio (2.4 ≤ R ≤ 12), and duty cycle (0.17 ≤ η ≤ 0.83) on the diffusion of low-frequency pulsed buoyant triple jets. A large number of simulations were conducted for each parameter, and the concentration field, vorticity field, and flow field at different sections during the initial stage of the jet were analyzed. The results reveal the evolution patterns of the vortex structure in pulsed triple buoyant jets and their diffusion characteristics. The vortex structure at the initial stage of the jet exhibits continuous vortex ring characteristics, which later evolve into a vortex street and counter-rotating vortex pair (CVP) combination structure. Meanwhile, the buoyancy effect enhances the development and diffusion of the vortex structure in both the X and Z directions. As the stroke ratio decreases, the wastewater concentration distribution becomes more concentrated, and the dynamic interaction between the jets intensifies. The increase in duty cycle enhances the interaction between the jets, significantly improving the horizontal diffusion capacity, but the vertical penetration depth is less than that of continuous jets. The Strouhal number (St) is composed of the stroke ratio, velocity ratio, and duty cycle. These three parameters control the motion state of pulsed jets in the crossflow. The established relationships and equations arising from this research offer vital reference values for predicting sewage leakage and wastewater diffusion in engineering applications, contributing substantively to the theoretical framework governing multiple buoyant jets.

Pharmacokinetics of Tarlatamab, a Delta-Like Ligand-3 (DLL3) Targeted Half-Life Extended Bispecific T-Cell Engager (BiTE®) Immunotherapy in Adult Patients with Previously Treated Small-Cell Lung Cancer: Results from DeLLphi-300, a Phase I Multiple-Dose-Escalation Study.

Tarlatamab binds to delta-like ligand 3 on cancer cells and cluster of differentiation-3 on T cells, leading to T-cell-mediated tumor lysis, and has demonstrated a promising safety and efficacy profile in patients with previously treated small-cell lung cancer (SCLC). Here, we present pharmacokinetic results from DeLLphi-300 (NCT03319940), an ongoing international, open-label, first-in-human study in previously treated adult patients with SCLC. Multiple escalating doses of tarlatamab were administered every 2 weeks (Q2W; 0.003, 0.01, 0.03, 0.1, 0.3, 1, 3, 10, 30, and 100 mg) in a 28-day cycle. To reduce the risk of cytokine-release syndrome, starting at the 3 mg dose level, a step dose regimen was employed consisting of a 1 mg infusion on cycle 1 day 1 (C1D1), followed by the target dose on C1D8, C1D15, and Q2W thereafter. All doses were infused over 1 h. Other tarlatamab dosing regimens were also explored, either for patient convenience (every 3 weeks) or to mitigate cytokine-release syndrome (extended intravenous infusion over a period of 3 days). Intensive pharmacokinetic samples were collected during cycles 1 and 2, and additional samples for pharmacokinetic and immunogenicity measurement were collected at regular intervals in later cycles. Pharmacokinetic data were analyzed using noncompartmental analysis, and antidrug antibody (ADA) incidence, including any effect on tarlatamab pharmacokinetic parameters, was summarized. Pharmacokinetic data were available from 203 patients. The median age was 62 years (range 32-80), and 55.7% (n = 113) of patients were male, 78.3% (n = 159) were white, and 8.3% (n = 17) were of Japanese descent. Following intravenous infusion, serum tarlatamab concentrations declined with time in a biphasic manner. Serum exposures increased in an approximately dose-proportional manner across the evaluated target dose range with a mean (standard deviation) estimated terminal phase elimination half-life of 5.8 (1.6) days, and steady state achieved by approximately C2D15. Of the 183 evaluable patients, 12 (6.6%) developed treatment-emergent ADAs; the distribution of dose-normalized serum concentrations were similar between patients who were ADA positive and ADA negative. In addition, the distribution of exposures was comparable in Japanese and non-Japanese patients. In patients with previously treated SCLC, tarlatamab demonstrated dose-proportional pharmacokinetic and extended half-life characteristics that support a Q2W dosing interval. Neither Japanese race nor ADA had a clinically relevant impact on exposures.

Theory of Gas Purification by Liquid Absorber in Small Rotating Channels with Application to the Patented Rotational Absorber Device

A new design for absorbing vapour-phase impurities from gases is presented. It consists of small channels packed in a rotating vertical cylinder. Gas flows through the channels adjacent to a thin film of absorber liquid. The liquid film is pressed to the radially outward side of each channel by the centrifugal force and flows downwards by gravity. Formulae are presented which describe the concentration distributions of gaseous impurities subject to absorption in gas and liquid. Results include expressions for laminar and turbulent diffusion coefficients to be used in mass balance equations. The role of rotation is quantified including the effect on wavy motion and enhanced diffusion in the liquid layer. Application in design is indicated for the case of separation of the greenhouse gas CO2 from flue gases of fossil fuel combustion processes. At other equal dimensions, the height of the Rotational Absorber Device is calculated to be 25 times shorter than the enormous heights of conventional tray and packed columns.

First Investigation of Long-Term Methane Emissions from Wastewater Treatment Using Satellite Remote Sensing

Wastewater treatment (WWT) contributes 2–9% of global greenhouse gas (GHG) emissions. The noticeable uncertainty in emissions estimation is due in large part to the lack of measurement data. Several methods have recently been developed for monitoring fugitive GHG emissions from WWT. However, limited by the short duration of the monitoring, only “snapshot” data can be obtained, necessitating extrapolation of the limited data for estimating annual emissions. Extrapolation introduces substantial errors, as it fails to account for the spatial and temporal variations of fugitive emissions. This research evaluated the feasibility of studying the long-term CH4 emissions from WWT by analyzing high spatial resolution Sentinel-2 data. Satellite images of a WWT plant in Calgary, Canada, taken between 2019 and 2023, were processed to retrieve CH4 column concentration distributions. Digital image processing techniques were developed and used for extracting the time- and space-varying features of CH4 emissions, which revealed daily, monthly, seasonal, and annual variations. Emission hotspots were also identified and corroborated with ground-based measurements. Despite limitations due to atmospheric scattering, cloud cover, and sensor resolution, which affect precise ground-level concentration assessments, the findings reveal the dynamic nature of fugitive GHG emissions from WWT, indicating the need for continuous monitoring. The results also show the potential of utilizing satellite images for cost-effectively evaluating fugitive CH4 emissions.

A refined model of lithium-ion battery considering agglomerated active material and non-uniform graphite particle

This study presents a refined lithium-ion battery model based on the Newman model, incorporating agglomerate structures in the positive electrode and non-uniform particle size distribution in the negative electrode. The agglomerates in the positive region consist of nano-scale primary particles, pore spaces, and binders, while the negative region features a random distribution of particle sizes. The model employs the volume averaging method and integrates a thermal model to provide a comprehensive simulation framework. The results of the numerical calculations and experimental measurements show that the model is in good agreement with the experimental data. The predicted discharge capacity of the proposed model is significantly higher than that of the traditional P2D model. This improvement is primarily due to the increased diffusion distance in agglomerates and the non-uniform particle sizes, which result in substantial changes in overpotential, electrolyte concentration, and solid-phase lithium-ion distribution. The model effectively captures the complex electrochemical behavior during discharge, underscoring the importance of considering structural heterogeneities in battery modeling.