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Abstract Top-spray configurations are widely used in pharmaceutical fluidized beds for particle coating and granulation. The process is complex due to the change of particle moisture as well as particle density. It is important to investigate the flow hydrodynamics in the process. In this paper, electrical capacitance tomography (ECT) combined with pressure transducers are used to investigate the flow hydrodynamics of gas-solids flow in a top-spray fluidized bed for wetting and drying. The flow characteristics investigated include bubble size, dominant frequency and standard deviation. Discrete wavelet transforms (DWT) and Fast Fourier Transform (FFT) are used to analyze the capacitance and pressure signals. The effects of key process parameters, including superficial velocity, particle size and spraying conduction on the flow hydrodynamics, are analyzed. The result indicates that both the material moisture and particle size influence the minimum fluidized velocity and bubble characteristics during the wetting and drying process. The result also indicates that the moisture content of particles and superficial fluidization velocity are two main factors, which determine the bubble characteristics in the top-spray process. The bubble size presents a complex trend, which is influenced by the spray pressure. The fluctuation frequency of bubbles presents a different trend in the wetting and drying stage.

Abstract Top-spray configurations are widely used in pharmaceutical fluidized beds for particle coating and granulation. The process is complex due to the change of particle moisture as well as particle density. It is important to investigate the flow hydrodynamics in the process. In this paper, electrical capacitance tomography (ECT) combined with pressure transducers are used to investigate the flow hydrodynamics of gas-solids flow in a top-spray fluidized bed for wetting and drying. The flow characteristics investigated include bubble size, dominant frequency and standard deviation. Discrete wavelet transforms (DWT) and Fast Fourier Transform (FFT) are used to analyze the capacitance and pressure signals. The effects of key process parameters, including superficial velocity, particle size and spraying conduction on the flow hydrodynamics, are analyzed. The result indicates that both the material moisture and particle size influence the minimum fluidized velocity and bubble characteristics during the wetting and drying process. The result also indicates that the moisture content of particles and superficial fluidization velocity are two main factors, which determine the bubble characteristics in the top-spray process. The bubble size presents a complex trend, which is influenced by the spray pressure. The fluctuation frequency of bubbles presents a different trend in the wetting and drying stage.

An integrated approach to document high anammox activity and biodiversity in a constructed wetland (CW) was performed and showed that substantial anammox activity could mitigate undesirable N(2)O emission. The enhanced anammox bacterial abundance, biodiversity and activity were achieved by supplementing activated sludge to the CW. Up to 3.38 × 10(7) gene copies g(-1) dry soil of anammox bacteria were enriched in the CW. The activity measured by isotope pairing technique increased from 1.6 nmol N g(-1) sludge h(-1) in the original activated sludge to 18 nmol N g(-1) soil h(-1) in the CW, with the specific cellular activity increased from 5.1 to 12.8 fmol cell(-1) d(-1). Up to 33% of produced N(2) could be attributed to anammox process in the CW, with the remainder being due to denitrification. Phylogenetic analysis of anammox bacterial 16S rRNA genes indicated a shift of community from single Candidatus "Brocadia fulgida" in sludge to multiple "Jettenia", "Brocadia", and "Anammoxoglobus" species in the CW. With static chambers and control experiments, the CW with supplemented sludge had a 30% reduced N(2)O emission flux compared with the tests without adding biomass during an 8 month testing period.

An integrated approach to document high anammox activity and biodiversity in a constructed wetland (CW) was performed and showed that substantial anammox activity could mitigate undesirable N(2)O emission. The enhanced anammox bacterial abundance, biodiversity and activity were achieved by supplementing activated sludge to the CW. Up to 3.38 × 10(7) gene copies g(-1) dry soil of anammox bacteria were enriched in the CW. The activity measured by isotope pairing technique increased from 1.6 nmol N g(-1) sludge h(-1) in the original activated sludge to 18 nmol N g(-1) soil h(-1) in the CW, with the specific cellular activity increased from 5.1 to 12.8 fmol cell(-1) d(-1). Up to 33% of produced N(2) could be attributed to anammox process in the CW, with the remainder being due to denitrification. Phylogenetic analysis of anammox bacterial 16S rRNA genes indicated a shift of community from single Candidatus "Brocadia fulgida" in sludge to multiple "Jettenia", "Brocadia", and "Anammoxoglobus" species in the CW. With static chambers and control experiments, the CW with supplemented sludge had a 30% reduced N(2)O emission flux compared with the tests without adding biomass during an 8 month testing period.

Aim of this study is to quantify the impacts of climate change on phenology and yield of winter wheat in rainfed and irrigated regions of Pakistan by using integration of two well-known crop models including STICS and APSIM with CORDEX-SA regional climate models (RCMs). A number of different adaptation strategies based on early sowing (i.e. S1:10 and S2:20 days), irrigation (I1:15% and I2:30% additional water) and a combination of sowing and irrigation adaptations were examined to recover the potential losses that would occur due to climate change. The data for the wheat phenology, biomass (t/ha) at different stages and yield (t/ha) was obtained from several experiments at national research institutes in Pakistan under both rainfed and irrigated conditions. After calibration and validation of both crop models (STICS and APSIM), the current climate data were replaced with the CORDEX-SA RCM-projections for climate change impact analysis. A significant rising and declining trends were observed in temperature and precipitation patterns, respectively, for the selected study regions. Consequently, a substantial impact of climate change on wheat phenology (anthesis stage, maturity stage, growing length), biomass (t/ha) and yield (t/ha) was observed under scenario periods for RCP4.5 and RCP8.5. Additionally, the adaptation strategies on wheat for rainfed regions showed a substantial improvement in wheat biomass and yield simulated by STICS model particularly for sowing-2 under RCP4.5. Irrigated regions showed more improvement for irrigation-2 (I2) and combination of sowing-1 + irrigation-2 (S1 + I2) using the STICS model under both RCPs. Overall, it was observed that changes in crop phenology had a stronger impact in terms of crop yield for RCP8.5 as compare to RCP4.5. This study provides a valuable understanding and way forward for the better wheat management under changes in precipitation and temperature patterns. The study also discuss in detail, the adaptation strategies to cope with potential damage, over two different irrigation zones (rainfed and irrigated) in Pakistan.

Aim of this study is to quantify the impacts of climate change on phenology and yield of winter wheat in rainfed and irrigated regions of Pakistan by using integration of two well-known crop models including STICS and APSIM with CORDEX-SA regional climate models (RCMs). A number of different adaptation strategies based on early sowing (i.e. S1:10 and S2:20 days), irrigation (I1:15% and I2:30% additional water) and a combination of sowing and irrigation adaptations were examined to recover the potential losses that would occur due to climate change. The data for the wheat phenology, biomass (t/ha) at different stages and yield (t/ha) was obtained from several experiments at national research institutes in Pakistan under both rainfed and irrigated conditions. After calibration and validation of both crop models (STICS and APSIM), the current climate data were replaced with the CORDEX-SA RCM-projections for climate change impact analysis. A significant rising and declining trends were observed in temperature and precipitation patterns, respectively, for the selected study regions. Consequently, a substantial impact of climate change on wheat phenology (anthesis stage, maturity stage, growing length), biomass (t/ha) and yield (t/ha) was observed under scenario periods for RCP4.5 and RCP8.5. Additionally, the adaptation strategies on wheat for rainfed regions showed a substantial improvement in wheat biomass and yield simulated by STICS model particularly for sowing-2 under RCP4.5. Irrigated regions showed more improvement for irrigation-2 (I2) and combination of sowing-1 + irrigation-2 (S1 + I2) using the STICS model under both RCPs. Overall, it was observed that changes in crop phenology had a stronger impact in terms of crop yield for RCP8.5 as compare to RCP4.5. This study provides a valuable understanding and way forward for the better wheat management under changes in precipitation and temperature patterns. The study also discuss in detail, the adaptation strategies to cope with potential damage, over two different irrigation zones (rainfed and irrigated) in Pakistan.

Wastewater is rich in nutrients, while desert regions often suffer from severe nutrient shortages, potentially leading to eutrophication and desertification in respective landscapes. Cyanobacterial cultivation emerges as a promising solution by extracting nutrients from wastewater and transferring them to deserts using cyanobacteria-induced biocrust technology. In this study, two biocrust inducing cyanobacteria, Microcoleus vaginatus and Scytonema javanicum were cultivated in synthetic and municipal wastewater, respectively, to assess their capabilities of nutrient removal and biocrust induction. Both cyanobacteria demonstrated effective removal of nitrogen and phosphorus from either synthetic or municipal wastewater, achieving removal rates exceeding 90 %. Sterilization experiments on the municipal wastewater confirmed that indigenous microorganisms did not influence cyanobacterial performance, though the two cyanobacteira exhibited contrasting growth and metabolic behaviors. Specifically, S. javanicum achieved higher biomass accumulation, reaching up to 6.05 ± 0.87 mg Chl-a L−1, whereas M. vaginatus produced more exopolysaccharides, up to 40.98 ± 2.96 mg L−1 in the municipal wastewater. The cyanobacteria harvested from the municipal wastewater effectively promoted biocrust formation, validating the feasibility of transferring nutrients from wastewater to deserts through cyanobacteria-induced biocrusts. Considering their varied growth behaviors, our findings advocate for the use of a combination of diverse cyanobacteria strains to optimize cultivation and inoculation technologies. Fil: Fernandez, Mariela Alejandra. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Tecnología de Recursos Minerales y Cerámica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Tecnología de Recursos Minerales y Cerámica; Argentina Fil: Montes, María Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Zhang, Cheng. Chinese Academy of Sciences; República de China Fil: Song, Shaoxian. Wuhan University of Technology; China Fil: Vadiveloo, Ashiwin. Murdoch University; Australia Fil: Xia, Ling. Wuhan University of Technology; China Fil: Lan, Shubin. Northeast Normal University; China Fil: Wu, Li. Northeast Normal University; China

Wastewater is rich in nutrients, while desert regions often suffer from severe nutrient shortages, potentially leading to eutrophication and desertification in respective landscapes. Cyanobacterial cultivation emerges as a promising solution by extracting nutrients from wastewater and transferring them to deserts using cyanobacteria-induced biocrust technology. In this study, two biocrust inducing cyanobacteria, Microcoleus vaginatus and Scytonema javanicum were cultivated in synthetic and municipal wastewater, respectively, to assess their capabilities of nutrient removal and biocrust induction. Both cyanobacteria demonstrated effective removal of nitrogen and phosphorus from either synthetic or municipal wastewater, achieving removal rates exceeding 90 %. Sterilization experiments on the municipal wastewater confirmed that indigenous microorganisms did not influence cyanobacterial performance, though the two cyanobacteira exhibited contrasting growth and metabolic behaviors. Specifically, S. javanicum achieved higher biomass accumulation, reaching up to 6.05 ± 0.87 mg Chl-a L−1, whereas M. vaginatus produced more exopolysaccharides, up to 40.98 ± 2.96 mg L−1 in the municipal wastewater. The cyanobacteria harvested from the municipal wastewater effectively promoted biocrust formation, validating the feasibility of transferring nutrients from wastewater to deserts through cyanobacteria-induced biocrusts. Considering their varied growth behaviors, our findings advocate for the use of a combination of diverse cyanobacteria strains to optimize cultivation and inoculation technologies. Fil: Fernandez, Mariela Alejandra. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Tecnología de Recursos Minerales y Cerámica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Tecnología de Recursos Minerales y Cerámica; Argentina Fil: Montes, María Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Zhang, Cheng. Chinese Academy of Sciences; República de China Fil: Song, Shaoxian. Wuhan University of Technology; China Fil: Vadiveloo, Ashiwin. Murdoch University; Australia Fil: Xia, Ling. Wuhan University of Technology; China Fil: Lan, Shubin. Northeast Normal University; China Fil: Wu, Li. Northeast Normal University; China