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This research used a qualitative and quantitative approach to classify factors influencing wheat farmers' social, economic, and environmental vulnerability in Khorasan Razavi province, Iran, from the perspective of elite wheat farmers and agricultural specialists, and then to establish some recommendations based on the results. To achieve the study objectives, in the qualitative part, in-depth interviews were held with 20 agricultural specialists in the field of wheat cultivation, and 9 elite wheat farmers were selected using a purposive sampling method. Using stratified random sampling, 391 wheat farmers participated in the quantitative part. From the agricultural specialists' viewpoint, the prime factor affecting vulnerability was the social factor "farm management". The second factor was the environmental vulnerability factor "Sunn pest and heat", and the final factor was the economic vulnerability factor "the costs of fertilizer, equipment, and machines and their maintenance". In contrast, from the viewpoint of elite wheat farmers, the dominant factor affecting vulnerability was the economic factor "the costs of equipment, fertilizer, and machines and their maintenance". Regarding social vulnerability, "Governmental support" was stressed and the most important environmental vulnerability factor was "Sunn pest and cold". The results of confirmatory factor analysis were more in line with the views of agricultural specialists. According to the results, it is suggested that the agricultural extension system provides timely training to farmers in order to properly manage farms in times of crisis. The government should also compensate part of the costs of social and economic damage to farmers by providing free or low-interest loans.

This study reviews the recent advances and innovations in the application of additives to improve biomethane and biohydrogen production. Biochar, nanostructured materials, novel biopolymers, zeolites, and clays are described in terms of chemical composition, properties and impact on anaerobic digestion, dark fermentation, and photofermentation. These additives can have both a simple physical effect of microbial adhesion and growth, and a more complex biochemical impact on the regulation of key parameters for CH4 and H2 production: in this study, these effects in different experimental conditions are reviewed and described. The considered parameters include pH, volatile fatty acids (VFA), C:N ratio, and NH3; additionally, the global impact on the total production yield of biogas and bioH2 is reviewed. A special focus is given to NH3, due to its strong inhibition effect towards methanogens, and its contribution to digestate quality, leaching, and emissions into the atmosphere.

Abstract In this paper, the demand response of district heating for swimming pools and pool space air is proposed and applied in a swimming hall in Finland. Swimming halls have significant heat demands e.g., domestic hot water supply, space heating and pool water heating, and thus have much large heat storage capacity for the realization of district-heat based demand response. A dynamic building simulation tool IDA ICE was used to simulate whole swimming hall including pools and HVAC systems. In addition, a rule-based demand response algorithm which utilized dynamic district heat price was proposed and applied in the district heating control of the studied swimming hall. The results show that the large storing capacity of pool water promises the large amount of charged and discharged heat energy, and ensure the application of demand response of district heating in swimming hall. The application of demand response of district heating can increase the average pool water temperature from the normal setpoint of 26.5 °C to 27.3 °C. In addition, demand-response district heating control for the swimming pool water and pool space air decreases the total district heat costs of the swimming hall by 1.1%. During the repayment periods of 7 and 15 years, the energy cost savings and maximum cost of profitable investment for the demand response control are between 10 000 € and 20 000 €.

Recently, it was hypothesized that ectomycorrhizas hyphae are involved in mineral tunneling. We evaluated the role of ectomycorrhizas in mineral weathering and the ecosystem influx of basic cations by correlating mineral tunnel density to ectomycorrhizas density in two forest productivity gradients. The gradients, two gentle slopes in northern Sweden, are the result of groundwater movement and are characterized by reduced productivity upslope due to lower nitrogen availability. As expected, ectomycorrhizas density in the O horizon was higher upslope, where nitrogen availability was lower and where the vegetation was dominated by ectomycorrhizas plant species. We consistently found that tunnel formation in mineral grains was more intense in nutrient-poor sites, indicating a higher contribution of fungi to ecosystem influx of potassium and calcium. ectomycorrhizas density was positively correlated with feldspar tunnel density in the upper 2 cm of the E horizon. This suggests that ectomycorrhizas are involved in mineral tunneling. We discuss the possible involvement of ericoid mycorrhizas and saprotrophic fungi in feldspar tunneling and the role of the weathering status of mineral grains as additional factors controlling mineral funneling.

An important component of plant–soil feedbacks is how plant species identity and diversity influence soil organism communities. We examine the effects of grassland plant species growing alone and together up to a richness of 12 species on nematode diversity and feeding group composition, eight years after the establishment of experimental grassland plots at the BIODEPTH site in northern Sweden. This is a substantially longer time than most other experimental studies of plant effects on soil fauna. We address the hypotheses that (1a) higher species or functional diversity of plants increases nematode diversity, as well as influences nematode community composition. Alternatively, (1b) individual plant species traits are most important for nematode diversity and community composition. (2) Plant effects on soil organisms will decrease with increasing number of trophic links between plants and soil fauna.Plant species identity was often more important than plant diversity for nematode community composition, supporting hypothesis 1b. There was a weak positive relation between plant and nematode richness, which could be attributed to the presence of the legume Trifolium pratense, but also to some other plant species, suggesting a selection or sampling effect. Several plant species in different functional groups affected nematode community composition. For example, we found that legumes increased bacterial‐feeding nematodes, most notably r‐selected Rhabditida, while fungal‐feeding nematodes were enhanced by forbs. Other bacterial feeders and obligate root feeders were positively related to grasses. Plant effects were usually stronger on plant‐, bacterial‐ and fungal‐feeding nematodes than on omnivores/predators, which supports hypothesis 2.Our study suggests that plant identity has stronger effects than plant diversity on nematode community composition, but when comparing our results with similar previous studies the effects of particular plant species appear to vary. We also found that more productive plant species affected bacterial‐feeding nematodes more than fungal feeders. Moreover, we observed stronger effects the fewer the number of trophic links there were between a nematode feeding group and plants. Although we found clear effects of plants on soil nematodes, these were probably not large enough to result in strong and persistent plant–soil‐organism–plant feedback loops.

The effect of the multi-row nozzle arrangement to the thermal performance of an impinging solar receiver is studied, and new governingequations are introduced for modifying the earlier introduced i ...

Abstract: This paper considers the use of lignin during the preparation of phenol-formaldehyde resins. The effect of lignin on the properties of phenol-formaldehyde resins and materials based on them is studied. The obtained resins are characterized by differential scanning calorimetry (DSC). The results show that, in the case of increasing the concentration of lignin, the time of the polycondensation reaction, the energy of activation, and the curing time of lignin-containing resins increase. The main parameters of the lignin-containing resins correspond to GOST (State Standard) 20907–2016 except for the concentration of free formaldehyde. The obtained resins are used to obtain a foam composite material—phenolic foam. It is noted that phenolic foams based on resins containing 5–10% lignin in the composition have a higher compression strength in comparison with other samples. At a concentration of lignin in the resin of 20%, the compression strength of the ready-to-use thermal-insulation materials decreases relative to other samples, while it turns out to be impossible to obtain a foam material in the case of using a resin with 30% lignin. The results of the study make it possible to recommend the use of a small amount of lignin (5–10%) in the production of phenol-formaldehyde resins and further production of a thermal-insulation material with an increased compression strength. © 2023, Pleiades Publishing, Ltd.

Abstract Hydrogen is an important energy carrier in the transportation sector and an essential industrial feedstock for petroleum refineries, methanol, and ammonia production. Renewable energy sources, especially solar energy have been investigated for large-scale hydrogen production in thermochemical, electrochemical, or photochemical manners due to considerable greenhouse gas emissions from the conventional steam reforming of natural gas and oil-based feedstock. The solar steam methane reforming using molten salt (SSMR-MS) is superior due to its unlimited operation hours and lower total annualized cost (TAC). In this work, we extend the existing optimisation framework for optimal design of SSMR-MS in which machine learning techniques are employed to describe the relationship between solar-related cost and molten salt heat duty and establish relationships of TAC, hydrogen production rate and molten salt heat duty with independent input variables in the whole flowsheet based on 18,619 sample points generated using the Latin hypercube sampling technique. A hybrid global optimisation algorithm is adopted to optimise the developed model and generate the optimal design, which is validated in SAM and Aspen Plus V8.8. The computational results demonstrate that a significant reduction in TAC by 14.9 % ~ 15.1 %, and CO2 emissions by 4.4 % ~ 5.2 % can be achieved compared to the existing SSMR-MS. The lowest Levelized cost of Hydrogen Production is 2.4 $ kg−1 which is reduced by around 17.2 % compared to the existing process with levelized cost of 2.9 $ kg−1.