•Sensor devices based on a configuration of HZSM-5 zeolite films printed Pd-WO3 sensing film were prepared.•The selectivity of Pd-WO3 sensors is considerably improved by the printing of HZSM-5 ...zeolite films.•Selective detection of CO and methanol is achieved by printing with HZSM-5 and Pt/HZSM-5 films on the top of sensing layers.
In the present study, gas sensors based on Pd-loaded WO3 sensor layers were prepared and coated with zeolite films to improve the selectivity. The sensing behavior of such sensors was characterized using different single gases and mixtures to assess their selectivity. We observed that the selectivity of sensors based on Pd-WO3 can be significantly tailored towards specific target gases by adding a printed zeolite film. The use of an HZSM-5 zeolite film made the Pd-loaded WO3 sensor highly sensitive to CO, with a response of around 10 at 100 ppm CO. When Pt-modified HZSM-5 zeolite film was used, same sensor became sensitive to methanol, with a detection limit of 0.5 ppm even in the presence of high concentration of CO. Interestingly, the Pt-modified HZSM-5 film caused the catalytic conversion of CO, which resulted in a p-type response to CO. In addition, in the presence of methanol such a p-type response to CO was also observed in pure WO3 sensor. Based on the power-law response to oxygen, it is proposed that the resistive responses of all tested sensors were highly dependent on the oxygen content, indicating that oxygen adsorbates on the surface were involved in the fundamental sensing mechanism, which is the same process as conventional gas sensors. The present study showed that the configuration of Pd-WO3 sensing layers coated with zeolite films is viable for tailoring the selectivity of gas sensors.
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•As an additive on copper foil electrodeposition, gelatin restrains the copper grain growth in the lateral direction parallel to the surface.•Gelatin causes the increase of the local ...misorientation and of the internal stresses on both the shiny and the matte sides.•Hydrogen gas release is accelerated at strong convection but hindered by gelatin.•Spiral-shaped pattern forms on the matte side of copper foil at strong convection in the presence of gelatin.
Copper foil electrodeposition has been explored using a pure titanium rotating disk electrode (RDE) in acidic electrolytes containing gelatin and/or chloride ions under different convection conditions. In the plating bath without gelatin, the results indicate that stronger convection promotes hydrogen evolution, which reduces the current efficiency during copper plating. Gelatin restrains the growth of copper grains in the lateral direction parallel to the surface. This results in grain refinement on the shiny side, an increase in local grain misorientation and in internal stresses on both the shiny and the matte side, and a reduction in their internal stress difference. At strong convection conditions and with gelatin present, copper deposits as strip-like grains along the centrifugal direction of the cross section, and finally forms a spiral-shaped pattern on the matte side. The causes of these features are discussed in detail. The combined influences of hydrogen and gelatin adsorption are further elaborated in a model for a copper deposition. The current investigation suggests that a moderate convection (somewhat lower than 1000rpm) and a concentration of 2ppm gelatin in the plating bath are sufficient for copper foil fabrication in the presence of chloride ions (20ppm).
Field monitoring of methane emissions from landfills is of great importance for both environmental concern and economic benefit. This study presents a highly effective method to measure methane ...emissions from landfills based on tunable diode laser absorption spectroscopy (TDLAS). Methane concentration is obtained by analyzing the absorption spectrum of the laser after passing through the landfill gas. The relationship between methane concentration and the optical signal was calibrated in the laboratory. As the methane concentration increased from 400 ppm to 5000 ppm, the absorption spectrum amplitude increased linearly from 0.0005 to 0.0046. In situ testing of methane emissions at a large-scale landfill in China demonstrated the accuracy of the TDLAS method. The methane concentrations in the well-covered areas were generally below 100 ppm. In the working area or the coverage area with holes, the methane concentration was about 700 ppm. The methane concentration was up to 1900 ppm, where the gas collection pipe is disconnected. Due to to the accuracy and simplicity, the TDLAS method is suitable to detect methane emissions on a large-scale from landfills.
One Health relies on decent partnerships, institutional structures, and a culture that supports One Health's perspectives and goals. The framework of One Health governance is more than accountability ...but also shared understanding and trust along with an appreciation for different moods and needs. Improved governance is critical to strengthening One Health's capacity. However, most countries need new forms of governance to prepare for the complex challenges and multi-actor responses required to combat infectious and non-infectious diseases. The government's construction and governance capacity building will be the starting point for integrating the concept of One Health into the social governance system and building a One Health governance system. This article reviews the connotations of the legal, governmental, technical, and support systems to show precisely the critical factors related to constructing a One Health governance system. The One Health approach solves complicated health problems from a holistic view of the “human-animal-environment” and improves public health governance performance through operating One Health governance.
WO
3
nanosheets was prepared by an acidification method and the Rh catalyst was dispersed on the surface of the nanosheets with a wet impregnation method. The morphology of pristine WO
3
and Rh ...modified WO
3
nanosheets and their responses to acetone gas were studied. According to oxygen adsorption combined with TPR results, the sensing and sensitization mechanism of acetone were discussed. It was found that no visible changes in nanostructures or morphologies were observed in WO
3
nanosheets with Rh, however, the sensor resistance and sensor response were greatly promoted. The basic sensitization mechanism could be caused by the electronic interaction between oxidized Rh and WO
3
surface.
In the 21st century, as globalization accelerates and global public health crises occur, the One Health approach, guided by the holistic thinking of human-animal-environment and emphasizing ...interdisciplinary collaboration to address global health issues, has been strongly advocated by the international community. An immediate requirement exists for the creation of an assessment tool to foster One Health initiatives on both global and national scales.
Built upon extensive expert consultations and dialogues, this follow-up study enhances the 2022 global One Health index (GOHI) indicator system. The GOHI framework is enriched by covering three indices, e.g. external drivers index (EDI), intrinsic drivers index (IDI), and core drivers index (CDI). The comprehensive indicator system incorporates 13 key indicators, 50 indicators, and 170 sub I-indicators, utilizing a fuzzy analytic hierarchy process to ascertain the weight for each indicator. Weighted and summed, the EDI, IDI, and CDI scores contribute to the computation of the overall GOHI 2022 score. By comparing the ranking and the overall scores among the seven regions and across 160 countries/territories, we have not only derived an overall profile of the GOHI 2022 scores, but also assessed the GOHI framework. We also compared rankings of indicators and sub I-indicators to provide greater clarity on the strengths and weaknesses of each region within the One Health domains.
The GOHI 2022 performance reveals significant disparities between countries/territories ranged from 39.03 to 70.61. The global average score of the GOHI 2022 is 54.82. The average score for EDI, IDI, and CDI are 46.57, 58.01, and 57.25, respectively. In terms of global rankings, countries from North America, Europe and Central Asia, East Asia and Pacific present higher scores. In terms of One Health domains of CDI, the lowest scores are observed in antimicrobial resistance (median: 43.09), followed by food security (median: 53.78), governance (median: 54.77), climate change (median: 64.12) and zoonotic diseases (median: 69.23). Globally, the scores of GOHI vary spatially, with the highest score in North America while lowest in sub-Saharan Africa. In addition, evidence shows associations between the socio–demographic profile of countries/territories and their GOHI performance in certain One Health scenarios.
The objective of GOHI is to guide impactful strategies for enhancing capacity building in One Health. With advanced technology and an annually updated database, intensifying efforts to refine GOHI's data-mining methodologies become imperative. The goal is to offer profound insights into disparities and progressions in practical One Health implementation, particularly in anticipation of future pandemics.
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Cold-plate design is critical for controlling the operating temperature of lithium-ion batteries. Notably, the coolant temperature gradually increases along the flow direction, and the cooling ...performance worsens. To address this issue, a novel composite channel cold plate (CCCP) is proposed in this work, which combines a straight channel with topology optimization (TO) channel. For CCCP, the straight channel reduced the heat exchange area between the coolant and cold plate and increased the minimal battery temperature in the channel upstream region. The TO channel enhanced heat transfer in the downstream channel region and decreased the battery temperature. Compared with the conventional straight channel cold plate (SCCP) and TO cold plate (TOCP), the CCCP exhibited better battery temperature uniformity. The battery maximal temperature differences across the SCCP, TOCP, and CCCP setups were 6.48 °C, 5.98 °C, and 4.46 °C, respectively. In addition, the coolant flow rate of the CCCP was below 50 % of the SCCP or TOCP when the battery maximal temperature difference was 5 °C, implying that the CCCP saved more than 50 % of the pumping power. To further improve the battery temperature uniformity and decrease the coolant flow resistance, a double inlet-outlet CCCP was proposed. When the coolant flow rate was 0.5 g·s−1, for the CCCP the battery maximal temperature difference and pressure drop decreased by 23.09 % and 43.45 %, compared with a single inlet-outlet CCCP.
•A composite channel cold plate (CCCP) is proposed to increase the battery temperature uniform.•CCCP combines straight channel with topology optimization (TO) channel.•A double inlet-outlet CCCP is developed to further improve the cooling effect.
•Sensors based on metal oxides resistively respond to O2 and obey the power-law response in the presence of reducing gases.•The receptor and transducer functions of O2 have been derived for metal ...oxides in the presence of reducing gases.•The power-law response of O2 is well observed in all sensors with one exception of Pd-loaded WO3 sensors.•The power-law response of O2 can be used to reveal the basic sensing mechanism of reducing gases.
This study presents a theoretical and experimental investigation on the power-law response to oxygen in the presence of reducing gases for metal oxide semiconductor gas sensors. In the presence of reducing gases, the exponents of power-law response to oxygen are derived, which allow us an effective probe to reveal the basic sensing mechanism. In order to obtain the power-law exponent, the transducer and receptor functions have been calculated in the presence of reducing gases. The transducer functions is built on two different conduction mechanisms, namely, Schottky barrier model and grain model. The receptor functions have been calculated by using the law of mass action for oxygen with different concentrations of reducing gases. The power response of SnO2 to oxygen has been characterized in the presence of CO and found to be well consistent with theoretical expectation.
How species respond to environmental change is a fundamental question in ecology and species traits can help to tackle this question. In this study, we analyze how the functional structure of species ...assemblages changes with selected environmental variables along an elevational gradient. In particular, we used species traits of local butterfly communities (body size, voltinism, overwintering stages, and host specificity) in a national nature reserve in China to assess the impacts of temperature, net primary productivity, and land use. Our results show that productivity, measured as NDVI, had a stronger influence on the functional community structure of butterflies than temperature. Within the butterfly assemblages, net primary productivity mainly affected body size and supported few but large species. Length of vegetation period demonstrated dominating effects on the functional structure of local butterfly assemblages. However, an observed increase in dietary generalists with longer vegetation periods contradicted expectations based on niche breadth hypothesis, that more stable conditions should favor specialists. Furthermore, the general positive impact of vegetation period on species abundances differed considerably among functional groups. Only the group containing species hibernating as egg decreased with the length of vegetation period. Our results suggest that trait associations are instructive to explain environment–herbivore relationships, that resource availability can predominantly influence the functional composition of herbivore assemblages, and that conservation priority should be given to specialist butterfly species overwintering as egg, especially in the face of global warming.
Collembola are highly abundant and diverse soil animals and play key roles in litter decomposition and nutrient cycling. Given their functional significance, it is important to understand their ...responses to human-induced global changes, such as climate change and land-use intensification. Here, we utilized an experimental field study, to test the interactive effects of climate (ambient vs. future) and land use (five land-use regimes, from extensively-used meadow to conventional farming) on three eco-morphological life forms of Collembola: epedaphic, hemiedaphic, and euedaphic species. We found that the effects of climate change on Collembola density were modulated by land use, and that the responses of different life forms to climate × land use interaction differed in magnitude and/or direction. The densities of total and hemiedaphic Collembola significantly decreased under organic farming and marginally increased in grasslands under future climatic conditions, whereas epedaphic Collembola tended to decrease their density with climate change in grasslands. In contrast, the density of euedaphic Collembola significantly increased with climate change in intensively-used grasslands. Further, we found that grasslands (especially extensively-used meadow) support the most abundant Collembola communities, with high species richness but low evenness. Multivariate analyses revealed independent effects of climate change and land-use intensification on Collembola community composition. Together, our findings indicate that the effects of climate change on Collembola communities depend on their life forms and land-use types. Surface-dwelling Collembola are more vulnerable to land use and climate change than those living in deeper soil layers. This may slow down the process of soil-surface litter decomposition in a changing world.
•Climate-change effects on Collembola communities depended on their life forms and land-use types.•Climate-change effects on densities of Collembola communities were modulated by land use.•Consistent land-use effects on species richness of Collembola communities under ambient and future climatic conditions.•Independent climate and land use effects on community composition of Collembola.
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