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The H( d, γ)He capture reaction and the H( d, p)H and H( d, n)He transfer reactions at very low energies are studied in an extended microscopic cluster model with a realistic nucleon-nucleon force. Our results show that the tensor force in realistic interactions plays an essential and indispensable role to reproduce the very low-energy astrophysical S factor of these reactions. [ABSTRACT FROM AUTHOR]

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The reaction rate is obtained for the reactionsH(p, γ)He,H(d, p)H,H(d, n)He,H(d, n)He,He(d, p)He,H(α, γ)Li,He(He, 2p)He,He(α, γ)Be at T∼300K. The distribution of relative velocities between two different sets of particles is described by Maxwell-Boltzmann distribution. The fusion cross-section is determined by using the extended elastic model II. [ABSTRACT FROM AUTHOR]

Copyright of Il Nuovo Cimento: A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The measurements of (d+d)-fusion on palladium target saturated with gaseous deuterium were taken at the energy of incident deuterons from 6 keV to 20 keV. The results are in good agreement with the known data about (d+d) cross-sections, extrapolated to the low-energy region. The possible «cold» nuclear fusion contribution to (d+d) cross-sections at low energy were not observed. [ABSTRACT FROM AUTHOR]

Recent fusion cross-section data for the reactionH(d, n)HeH(d, p)H are compared with the predictions of the, «extended elastic model II». A comparison with cluster-impact fusion results is also given. [ABSTRACT FROM AUTHOR]

Modelling and prediction of air quality facilitates the drafting of efficient guidelines and, in turn, proper management of adversely affected areas. In order to depict the air pollutants in urban centres, this research analyses two modelling tools: AERMOD and CALINE4. Both technologies provide distinct capabilities in the modelling of air quality from vehicular and other emissions. CALINE4, a Gaussian dispersion model, specifies pollutant dispersion from mobile sources along roadways. It boasts a user-friendly interface and road-specific modelling capabilities, factoring in traffic speed and vehicle emissions. However, it simplifies intricate flow patterns and relies on primary meteorological data. On the other hand, AERMOD is a versatile model suitable for various emission sources, including both mobile and stationary sources. It excels at capturing diverse atmospheric processes but demands precise meteorological, terrain, and emission data. AERMOD is often preferred for regulatory compliance assessments, although it entails a steeper learning curve and higher computational requirements. The choice between CALINE4 and AERMOD hinges on study needs, data availability, and desired modelling precision. This review offers an overview to assist researchers in making informed model selections for assessing vehicle-related pollution, critical aspects of urban sustainability, and air quality management., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

An efficient approach for calculating the far field pattern of conformal phased array antennas mounted on cylindrical-shaped platforms is proposed. The array structure is taken into account by using an active element pattern technique, and the array is analyzed by using an element-by-element approach. The effects of all mutual couplings in the array environments are considered rigorously, and the efficiency of the proposed method is validated by using the commercial full-wave simulation software HFSS. Finally, a low side-lobe cylindrical phased array is designed for engineering by optimizing phases and amplitudes of port excitations. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5 ) and volatile organic compounds (VOCs) are associated with adverse health effects and show spatial variation in three dimensions. The present study attempted to evaluate source contributions of PM 2.5 and toxic VOCs in a metropolitan area focusing on the associated vertical variations. A special emphasis is put on the effects of the elevated expressway on the vertical variability of contribution estimates of the identified sources. Nine source factors, i.e., soil dust, sea salt/oil combustion, secondary nitrate, industrial emission, aged VOCs/secondary aerosol, traffic-related I, solvent use/industrial process, secondary sulfate, and traffic-related II, were identified using positive matrix factorization (PMF). The main contributors to PM 2.5 were secondary sulfate (19.1%) and traffic-related emissions (traffic-related I and II, 16.1%), whereas the largest contributors to VOCs were traffic-related emissions (37.6%). The influence of the elevated expressway is suggested to be particularly critical on vertical variations of traffic-related emissions, including aging and secondary formation of locally accumulated air pollutants near roads. Increasing the building porosity under the viaduct could reduce the accumulation of air pollutants caused by the shelter effect. Additionally, in-street barriers would be beneficial in reducing population exposure to traffic-related emissions by altering the airflows near roads., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Despite the pivotal role of the egg industry in the food supply chain, the absence of regular surveys over the past decades in Taiwan has resulted in a dearth of national-level data. This study endeavours to address the research void surrounding biosecurity while scrutinizing the technical efficiency of egg producers in an environment where there is no mandate to phase out battery cage systems and farmers have the autonomy to adjust their feeding strategies. We employ the stochastic frontier analysis framework to analyse farm-level data derived from a 2020 national survey of the egg industry in Taiwan, which includes 547 commercial egg farms, with 519 still utilizing battery cages and 28 farms having transitioned into alternative systems to meet higher Farm Animal Welfare standards. Our findings reveal that egg farmers who prioritize the improvement of biosecurity demonstrate greater technical efficiency. When considering the rearing systems, there is no significant difference in egg production rates between conventional and alternative systems. However, conventional systems exhibit higher efficiency in terms of total output. In essence, elevating FAW standards does not exert a discernible impact on the productivity of laying hens. Instead, farms employing conventional systems attain greater output due to their higher stocking density. [ABSTRACT FROM AUTHOR]

For the rational manipulation of the production quality of high-temperature metallurgical engineering, there are many challenges in understanding the processes involved because of the black box chemical/electrochemical reactors. To overcome this issue, various in-situ characterization methods have been recently developed to analyze the interactions between the composition, microstructure, and solid–liquid interface of high-temperature electrochemical electrodes and molten salts. In this review, recent progress of in-situ high-temperature characterization techniques is discussed to summarize the advances in understanding the processes in metallurgical engineering. In-situ high-temperature technologies and analytical methods mainly include synchrotron X-ray diffraction (s-XRD), laser scanning confocal microscopy, and X-ray computed microtomography (X-ray μ-CT), which are important platforms for analyzing the structure and morphology of the electrodes to reveal the complexity and variability of their interfaces. In addition, laser-induced breakdown spectroscopy, high-temperature Raman spectroscopy, and ultraviolet–visible absorption spectroscopy provide microscale characterizations of the composition and structure of molten salts. More importantly, the combination of X-ray μ-CT and s-XRD techniques enables the investigation of the chemical reaction mechanisms at the two-phase interface. Therefore, these in-situ methods are essential for analyzing the chemical/electrochemical kinetics of high-temperature reaction processes and establishing the theoretical principles for the efficient and stable operation of chemical/electrochemical metallurgical processes. [ABSTRACT FROM AUTHOR]

Under-viaduct space (UVS) is becoming an important solution to urban mobility problems, and the construction and use of high-density city center highways and elevated bridges are increasing, which has a negative impact on the UVS. Air pollution is a problem in these spaces, but research on air pollution in UVSs is lacking. To further study air pollution in UVS, this study selected a case area of a UVS in central Shanghai and investigated the spatiotemporal distribution patterns of air pollution and the influencing factors. We found that air pollution in the UVS is significantly higher than the background levels, and the higher the background levels, the greater the difference between the pollution of the UVS and the background. In terms of the impact factor, air pollution is highly correlated with the built environment and traffic flow. The research provides evidence of the exposure to air pollution in under viaducts spaces in the microenvironment. [ABSTRACT FROM AUTHOR]

In recent years, haze pollution in China has garnered significant attention from both the government and the public, with vehicle emissions being identified as a key source of pollution. This study analyzes the impact of the tail number restriction policy (TNRP) on air quality using daily data from Lanzhou, China, in 2020, by employing the regression discontinuity in time (RDiT) method. The results show that the TNRP significantly reduced the air quality index (AQI) and concentrations of PM2.5, PM10, NO2, and CO, indicating a positive effect on air quality, though this is not a long-term standalone solution. Unlike previous policies, the current TNRP restricts traffic during peak hours, yielding consistent effects. This study recommends continuing the restriction policy and developing a comprehensive environmental governance system to promote new energy vehicles and enhance public transportation infrastructure. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The operational principle of semiconductor devices critically relies on the band structures that ultimately govern their charge-transfer characteristics. Indeed, the precise orchestration of band structure within semiconductor devices, notably at the semiconductor surface and corresponding interface, continues to pose a perennial conundrum. Herein, for the first time, this work reports a novel postepitaxy method: thickness-tunable carbon layer decoration to continuously manipulate the surface band bending of III-nitride semiconductors. Specifically, the surface band bending of p-type aluminum-gallium-nitride (p-AlGaN) nanowires grown on n-Si can be precisely controlled by depositing different carbon layers as guided by theoretical calculations, which eventually regulate the ambipolar charge-transfer behavior between the p-AlGaN/electrolyte and p-AlGaN/n-Si interface in an electrolyte environment. Enabled by the accurate modulation of the thickness of carbon layers, a spectrally distinctive bipolar photoresponse with a controllable polarity-switching-point over a wide spectrum range can be achieved, further demonstrating reprogrammable photoswitching logic gates "XOR", "NAND", "OR", and "NOT" in a single device. Finally, this work constructs a secured image transmission system where the optical signals are encrypted through the "XOR" logic operations. The proposed continuous surface band tuning strategy provides an effective avenue for the development of multifunctional integrated-photonics systems implemented with nanophotonics., (© 2023 Wiley-VCH GmbH.)

A recent adaptation of the collisional cooling technique which permits gas-phase spectroscopy from 5 K to ≥20 K is described. The new apparatus was used to measure pressure broadening parameters and cross sections for the the J=0–1, K=0 rotational transition of CH3F broadened by helium from 5 to 21 K. The cross sections show a general upward trend with decreasing temperature ranging from 55.9 Å2 at 20 K, to 114.0 Å2, at 5 K. This compares with a 295 K cross section of 48.8 Å2. While an accurate CH3F–He potential surface is not presently available for calculating theoretical cross sections, the rise in cross section at low temperature can be attributed to the dominance of resonant collisional processes at very low energy. Although resonant structure in many systems (e.g., CO–He, H(D)Cl–He) appears to be smoothed out by Boltzmann averaging, there is experimental evidence that at least one resonance may survive the thermal average in the CH3F–He system. [ABSTRACT FROM AUTHOR]

Combined Thomson scattering (TS) and laser-induced fluorescence (LIF) diagnostics are being developed. The Thomson scattering and laser-induced fluorescence are laser diagnostics, with joint both probing and c-ollecting optical systems, which are the most complex and expensive parts of the diagnostic systems of large tokamaks, can be combined. Thomson scattering by free electrons is the use-proven diagnostic method for measuring profiles of important parameters of the plasma electron component (electron tempera-ture Te and electron density ne), which requires a minimum of model assumptions. Almost all existing tokamaks are equipped with one or more TS systems, and by now, considerable experience has been accumulated in practical methods for implementation of these systems. The use of laser-induced fluorescence for measuring parameters of ion and neutral plasma components is less common, also because it requires knowledge of electron parameters to calculate populations of excited levels. The joint diagnostics of the Thomson scattering and laser-induced fluorescence in divertor plasma will be used to simultaneously measure the plasma parameters necessary for fundamental understanding physics of plasma detachment from divertor plates. These parameters are: the local parameters of plasma electrons (Te, ne), ion temperature (Ti) measured from the data on emission of helium ions (HeII), as well as densities of helium atoms (na(He)) and hydrogen isotopes (na(H,D,T)). The measured parameters make it possible to calculate the following characteristics: (i) the ionization and recombination rates (using the data on Te, ne, Ti, and na(H, D, T)); (ii) the friction force of the plasma flow due to collisions with neutral particles (using the data on Ti, ni (assuming ni = ne), and na(H, D, T)); and (iii) the pressure of the oncoming plasma flow (using the data on Te, ne, Ti, and ni). The article discusses advantages of combining laser diagnostics and ways of further development of the joint diagnostcs, based on the experience of creating similar diagnostics for domestic tokamaks and the similar diagnostics developed for ITER. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai University / Shanghai Daxue Xuebao is the property of Journal of Shanghai University (Natural Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Investigating and assessing native fish diversity and conducting regional assessments of threats are vital for the conservation of aquatic biodiversity. For this specific study, the Daqing River basin in China was chosen as the research area. Field surveys were carried out between 2018 and 2019, supplemented by a review of pertinent literature and other records. Methods: To evaluate fish diversity, the following parameters are selected for analysis: Relative abundance (Pi), Frequency of occurrence (Fi), Margalef richness index (D), Shannon Wiener diversity index (H'), and Pielou evenness index (J').Relative abundance levels are categorized as follows: dominant species make up more than 10%, common species account for 1%--10%, and occasional species constitute less than 1%. Canoco 5.0 software was utilized to conduct Redundancy Analysis (RDA) on the fish species composition and environmental factors at 34 sampling sites. Results: The findings revealed that 85 fish species have been recorded in the basin, consisting of 78 freshwater species categorized into 8 orders, 17 families, and 59 genera, among which Cypriniformes comprised 64% of the total catch. The low proportion of threatened and endemic species was an important feature of the fish diversity of the Daqing River. Despite the theoretical presence of 85 species, field surveys managed to collect only 42 species, of which 33 were confirmed as naturally occurring within the basin. The average values of Margalef richness index, 22 Shannon Wiener diversity index and Pielou evenness index were 1.72, 2.04 and 0.80 respectively, signifying a low fish diversity with relatively uniform distribution across the sampled regions. Discussion: This study found that the community structure and diversity of fish were closely related to environmental factors, particularly water quality. Among these factors, ammonia nitrogen emerged as a significant determinant of fish diversity. High concentrations of ammonia nitrogen inhibit fish growth, endanger health, and can even lead to death. Additionally, dams and other water infrastructure also impact fish community structure and diversity. This baseline study can provide a basis for the protection and ecological restoration of fish resources in the Daqing River. [ABSTRACT FROM AUTHOR]