Facile Preparation of g-C3N4-WO3 Composite Gas Sensing Materials with Enhanced Gas Sensing Selectivity to Acetone

In this paper, g-C3N4-WO3 composite materials were prepared by hydrothermal processing. The composites were characterized by means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and N2 adsorption-desorption, respectively. The gas sensing properties of the composites were investigated. The results indicated that the addition of appropriate amount of g-C3N4 to WO3 could improve the response and selectivity to acetone. The sensor based on 2 wt% g-C3N4-WO3 composite showed the best gas sensing performances. When operating at optimum temperature of 310°C, the responses to 1000 ppm and 0.5 ppm acetone were 58.2 and 1.6, respectively, and the ratio of the S1000 ppm acetone to S1000 ppm ethanol reached 3.7

Biogeographic patterns and drivers of soil viromes

Viruses are crucial in shaping soil microbial functions and ecosystems. However, studies on soil viromes have been limited in both spatial scale and biome coverage. Here we present a comprehensive synthesis of soil virome biogeographic patterns using the Global Soil Virome dataset (GSV) wherein we analysed 1,824 soil metagenomes worldwide, uncovering 80,750 partial genomes of DNA viruses, 96.7% of which are taxonomically unassigned. The biogeography of soil viral diversity and community structure varies across different biomes. Interestingly, the diversity of viruses does not align with microbial diversity and contrasts with it by showing low diversity in forest and shrubland soils. Soil texture and moisture conditions are further corroborated as key factors affecting diversity by our predicted soil viral diversity atlas, revealing higher diversity in humid and subhumid regions. In addition, the binomial degree distribution pattern suggests a random co-occurrence pattern of soil viruses. These findings are essential for elucidating soil viral ecology and for the comprehensive incorporation of viruses into soil ecosystem models

On Predictive Patent Valuation: Forecasting Patent Citations and Their Types

Patents are widely regarded as a proxy for inventive output which is valuable and can be commercialized by various means. Individual patent information such as technology field, classification, claims, application jurisdictions are increasingly available as released by different venues. This work has relied on a long-standing hypothesis that the citation received by a patent is a proxy for knowledge flows or impacts of the patent thus is directly related to patent value. This paper does not fall into the line of intensive existing work that test or apply this hypothesis, rather we aim to address the limitation of using so-far received citations for patent valuation. By devising a point process based patent citation type aware (self-citation and non-self-citation) prediction model which incorporates the various information of a patent, we open up the possibility for performing predictive patent valuation which can be especially useful for newly granted patents with emerging technology. Study on real-world data corroborates the efficacy of our approach. Our initiative may also have policy implications for technology markets, patent systems and all other stakeholders. The code and curated data will be available to the research community

Synthesis of porous ZnFe2O4/SnO2 core-shell spheres for high-performance acetone gas sensing

For developing promising gas sensing materials, constructing porous and heterojunction structures within the whole semiconductor oxide composites was an ideal strategy. However, it was always difficult because there existed grain boundaries. Herein, the pre-synthesized tiny SnO2 nanospheres could be evenly combined with ZnFe2O4 to form the ZnFe2O4/SnO2 (ZFO/SNO) composite with porous core-shell spheres structure via a simple solvent thermal reaction followed by the calcination treatment. Molar ratios of Zn to Sn were adjusted, and the resultant porous ZFO/SNO composites with different morphology were obtained, and their gas sensing properties were investigated and compared. The result indicated that the porous ZFO/SNO composite with a Zn to Sn ratio of 1:0.7 (ZFO/SNO-0.7) showed much better acetone sensing performance than that of bare porous ZnFe2O4 spheres and other ZFO/SNO composites. It exhibited a high response value of 120 to 100 ppm of acetone at 210℃ with good stability, and the detection limit can reach 0.1 ppm. The remarkable sensor performance of the porous ZFO/SNO-0.7 composite was attributed to its rich heterojunctions, porous structure and small nanoparticle size

A facile cotton biotemplate to fabricate porous ZnFe₂O₄ sheets for acetone gas sensing application

Developing methods to synthesize semiconductor oxides with hierarchically porous architecture is an effective way to improve their sensing properties. Herein, a strategy using cotton as biotemplates involving immersion, solvothermal reaction and calcination has been developed to synthesize ZnFe₂O₄ with porous flaky and curly sheets structure. The calcination temperature was optimized, and sensing properties of the as-prepared porous ZnFe₂O₄ sheet composites were investigated. For comparison, without cotton template, ZnFe₂O₄ nanoparticle (NPs) was synthesized. Meanwhile, without solvothermal reaction, ZnFe₂O₄ mixture of fiber-like structure and NPs (ZnFe₂O₄ fiber/NPs) was obtained. Sensors based on these comparison samples showed poor sensing performance to various gases. Whereas, the sensor based on porous ZnFe₂O₄ sheet composite calcined at 600 ℃ exhibited good selectivity, fast response and stability to acetone, and a high response of 66.7–100 ppm was also obtained at 220 ℃. The good sensing performance of the porous ZnFe₂O₄ sheet composite was mainly attributed to its porous structure and the formation of heterojunctions with ZnO and Fe₂O₃ found in the composite. The strategy might also be an effective way to fabricate other porous nanomaterials for applications besides ZnFe₂O₄

Rhodium as efficient additive for boosting acetone sensing by TiO2 nanocrystals. Beyond the classical view of noble metal additives

Anatase TiO2 nanocrystals were prepared by solvothermal synthesis and modified by in- situ generated Rh nanoparticles, with a starting nominal Rh:Ti atomic concentration of 0.01 and 0.05. After heat-treatment at 400 °C the TiO2 host was still in the anatase crystallographic phase, embedding Rh nanoparticles homogeneously distributed and whose surface had been oxidized to Rh2O3, as established by X-ray diffraction, Transmission Electron Microscopy and X-ray Photoelectron spectroscopy. Moreover, Rh seemed also homogeneously distributed in elemental form or as Rh2O3 nanoclusters. The acetone sensing properties of the resulting materials were enhanced by Rh addition, featuring a response increase of one order of magnitude at the best operating temperature of 300 °C. Moreover, Rh addition enlarged the detection range down to 10 ppm whereas pure TiO2 was not able of giving an appreciable response already at a concentration as high as 50 ppm. From the sensing data, the enhancement of the sensor response was attributed to the finely dispersed Rh species and not to the oxidized Rh nanocrystals.ICN2 acknowledge funding from Generalitat de Catalunya 2017 SGR 327 and the Spanish MINECO project ENE2017-85087-C3. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706) and is funded by the CERCA Programme / Generalitat de Catalunya. Part of the present work has been performed in the framework of Universitat Autònoma de Barcelona Materials Science PhD program. TZ has received funding from the CSC-UAB PhD scholarship program.Peer reviewe

Improving gut functions and egg nutrition with stevia residue in laying hens

ABSTRACT: This study aimed to investigate the effect of stevia residue (STER) on the production performance, egg quality and nutrition, antioxidant ability, immune responses, gut morphology and microbiota of laying hens during the peak laying period. A total of 270 Yikoujingfen NO. 8 laying hens (35 wk of age) were randomly divided into 5 treatments. The control group fed a basal diet and groups supplemented with 2, 4, 6, and 8% STER. The results showed that STER significantly increased egg production, the content of amino acids (alanine, proline, valine, ornithine, asparagine, aspartic acid, and cysteine) in egg whites, and decreased the yolk color (P < 0.05). Additionally, STER significantly increased acetate, HOMOγ linolenic acid and cis-13, 16-docosadienoic acid levels in egg yolk (P < 0.05). IL-2, IL-4, and IL-10 levels in serum significantly increased by STER (P < 0.05), while IL-1β significantly decreased (P < 0.05). STER also increased total antioxidant activity (T-AOC) in the liver and estradiol level in the oviduct (P < 0.05), but decreased the cortisol level in the oviduct (P < 0.05). For the intestinal morphology, the jejunal villus height and crypt-to-villus (V:C) significantly increased by STER (P < 0.05). STER increased the relative abundance of Actinobacteriota (P < 0.05), while deceased Proteobacteria, Desulfobacterota, and Synergistota (P < 0.05). In conclusion, STER improved egg production, quality and nutrition, improved the immune responses, antioxidant capabilities, estrogen level, gut morphology, and increased the relative abundance of beneficial bacteria while decreased the harmful bacteria. Among all treatments, 4 and 6% STER supplementation yielded the most favorable results in terms of enhancing production performance, egg nutrition, gut health, and immune capabilities in laying hens

Rhodium as efficient additive for boosting acetone sensing by TiO2 nanocrystals. Beyond the classical view of noble metal additives

Altres ajuts: ICN2 is funded by the CERCA Programme / Generalitat de Catalunya. Part of the present work has been performed in the framework of Universitat Autònoma de Barcelona Materials Science PhD program. TZ has received funding from the CSC-UAB PhD scholarship program.Anatase TiO nanocrystals were prepared by solvothermal synthesis and modified by in- situ generated Rh nanoparticles, with a starting nominal Rh:Ti atomic concentration of 0.01 and 0.05. After heat-treatment at 400 °C the TiO host was still in the anatase crystallographic phase, embedding Rh nanoparticles homogeneously distributed and whose surface had been oxidized to RhO, as established by X-ray diffraction, Transmission Electron Microscopy and X-ray Photoelectron spectroscopy. Moreover, Rh seemed also homogeneously distributed in elemental form or as RhO nanoclusters. The acetone sensing properties of the resulting materials were enhanced by Rh addition, featuring a response increase of one order of magnitude at the best operating temperature of 300 °C. Moreover, Rh addition enlarged the detection range down to 10 ppm whereas pure TiO was not able of giving an appreciable response already at a concentration as high as 50 ppm. From the sensing data, the enhancement of the sensor response was attributed to the finely dispersed Rh species and not to the oxidized Rh nanocrystals