Kinetics of mass transfer, colour, total polyphenol and texture change of Manilkara zapota during convective air drying

The effects of air temperature and product size on drying kinetics, retained total polyphenol content (TPC), hardness kinetics and total colour change (ΔE) kinetics of ciku (Manilkara zapota) were investigated. In addition, five terms of the theoretical model were used to estimate the effective diffusivity values during drying at temperatures from 40°C to 70°C. The drying rates of dried ciku were increased with increasing temperature and decreasing product size. It was found that hardness of ciku dried at temperature higher than 60°C increased significantly, when the moisture content was reduced to less than 0.5 g H2O/g DM (dry basis). In terms of nutritional value, the retained total polyphenol content (TPC) of dried ciku in hot air drying also increasing with temperature. The highest retained TPC was 141 mg GAE/ 100g of samples, which can be obtained from drying at 70°C

Drying models and quality analysis of sun-dried ciku

Sun drying of ciku (Manilkara zapota) was carried out on different sample sizes to investigate the effects on drying kinetics. It was found that the maximum drying rates of sun-dried ciku decreased with larger product size. Three sunny days are needed to dry the ciku slabs to an average final moisture content of 0.2 g H2O/g dry mass. The results showed that hardness and chewiness of the dried samples were significantly different (p 0.05) compared to fresh ciku slabs. In addition, sun-dried ciku retained a total polyphenol content (TPC) that was relatively low (p < 0.05) compared to fresh ciku

Drying kinetics, texture, color, and determination of effective diffusivities during sun drying of chempedak

Sun drying of chempedak (Artocarpus integer) was carried out on different sample sizes to investigate the effects on product quality. Fick's second law model was used to determine the effective diffusivities of sun–dried chempedak slabs based on the drying rate versus moisture content plots. In addition, texture degradation and total color changes were investigated. The texture and color changes of dried chempedak were relatively significant (p < 0.05) compared to fresh chempedak. There was an increase in dried fruit hardness and chewiness but a decrease in springiness and cohesiveness during drying

Photocatalytic study of two-dimensional ZnO nanopellets in the decomposition of methylene blue

We report several significant photodecomposition rates of methylene blue (MB) obtained before and after the refluxing process of own-synthesized two-dimensional (2D) zinc oxide (ZnO) nanopellets. Each photodecomposition rate of MB was found highly dependent on the weight of photocatalyst. The existing photodecomposition rate has been successfully improved to a factor of 22.0 times through refluxing process in excessive pyridine where the surface capping ligand (oleic acid) is removed from the 2D ZnO nanopellets. On the other hand, the refluxed photocatalyst (0.04 g) in this study was found to exhibit excellent recyclability up to three cycles. Furthermore, X-ray powder diffraction spectrums for the refluxed photocatatalyst, respectively, before and after three cycles of photocatalytic reactions, has generated the same patterns showing that the photocatalyst is stable and feasible to be used as an efficient photocatalyst material. Hence, these 2D ZnO nanopellets would provide a new alternative route as a highly efficient photocatalyst for wastewater treatment

Drying kinetics and product quality of dried chempedak.

The objective of this study was to investigate the drying kinetics of chempedak (Artocarpus integer) at different drying temperatures (50 °C, 60 °C, 70 °C) and slab dimensions. The drying data were fitted to the different semi-theoretical models based on moisture ratio (MR) to predict the drying kinetics. A logarithmic model was found to be the best fit in this study for all the drying temperatures tested. Effective diffusivities were estimated from Fick’s 2nd law and the Arrhenius equation was used to determine the diffusivity constant (Do) and activation energy (Ea). The texture and color of dried product were altered significantly during drying. The total color change (ΔE), hardness and chewiness were found to be increased with elevated temperature; meanwhile, springiness and cohesiveness of dried chempedak were relatively constant

Impacts of variations in Caspian Sea surface area on catchment-scale and large-scale climate

The Caspian Sea (CS) is the largest inland lake in the world. Large variations in sea level and surface area occurred in the past and are projected for the future. The potential impacts on regional and large-scale hydroclimate are not well understood. Here, we examine the impact of CS area on climate within its catchment and across the northern hemisphere, for the first time with a fully coupled climate model. The Community Earth System Model (CESM1.2.2) is used to simulate the climate of four scenarios: (1) larger than present CS area, (2) current area, (3) smaller than present area, and (4) no-CS scenario. The results reveal large changes in the regional atmospheric water budget. Evaporation (E) over the sea increases with increasing area, while precipitation (P) increases over the south-west CS with increasing area. P-E over the CS catchment decreases as CS surface area increases, indicating a dominant negative lake-evaporation feedback. A larger CS reduces summer surface air temperatures and increases winter temperatures. The impacts extend eastwards, where summer precipitation is enhanced over central Asia and the north-western Pacific experiences warming with reduced winter sea ice. Our results also indicate weakening of the 500-hPa troughs over the northern Pacific with larger CS area. We find a thermal response triggers a southward shift of the upper troposphere jet stream during summer. Our findings establish that changing CS area results in climate impacts of such scope that CS area variations should be incorporated into climate model simulations, including palaeo and future scenarios. Plain Language Summary The Caspian Sea is the largest land-locked water body in the world. It is filled by rivers draining a vast region from northern Russia to Iran. The size of the Caspian Sea has varied considerably over recent centuries and millennia due to various factors, including changes in climate. Conversely, as the area of the sea changes it also has impacts on the climate, but there are significant questions about how and where those impacts would be felt. In this study we used a state-of-the-art climate model in which we specified different sizes of Caspian Sea in order to examine how the climate changes as its area increases. We observed that the local seasonal cycle of temperatures gets smaller, and evaporation increases, while there are more spatially complex changes in local rainfall. Furthermore, the impacts on atmospheric circulation occur as far as the north Pacific, with resulting increases in temperature and decreases in sea-ice coverage in winter as the Caspian area increases. The climate impacts are so significant and geographically extensive that climate models used to simulate climate change (both in future and past scenarios) should incorporate changes to the Caspian Sea area if they are to robustly model regional climate

Hyperresolution information and hyperresolution ignorance in modelling the hydrology of the land surface

There is a strong drive towards hyperresolution earth system models in order to resolve finer scales of motion in the atmosphere. The problem of obtaining more realistic representation of terrestrial fluxes of heat and water, however, is not just a problem of moving to hyperresolution grid scales. It is much more a question of a lack of knowledge about the parameterisation of processes at whatever grid scale is being used for a wider modelling problem. Hyperresolution grid scales cannot alone solve the problem of this hyperresolution ignorance. This paper discusses these issues in more detail with specific reference to land surface parameterisations and flood inundation models. The importance of making local hyperresolution model predictions available for evaluation by local stakeholders is stressed. It is expected that this will be a major driving force for improving model performance in the future. Keith BEVEN, Hannah CLOKE, Florian PAPPENBERGER, Rob LAMB, Neil HUNTE

Governance and Susceptibility in Conflict Resolution: Possibilities Beyond Control

Governmentality analysis offers a nuanced critique of informal Western conflict resolution by arguing that recently emerged alternatives to adversarial court processes both govern subjects and help to constitute rather than challenge formal regulation. However, this analysis neglects possibilities for transforming governance from within conflict resolution that are suggested by Foucault's contention that there are no relations of power without resistances. To explore this lacuna, I theorise and explore the affective and interpersonal nature of governance in mediation through autoethnographic reflection upon mediation practice, and Levina's insights about the relatedness of selves. The paper argues that two qualitatively different mediator capacities - technical ability and susceptibility - operate in concert to effect liberal governance. Occasionally though, difficulties and failures in mediation practice bring these capacities into tension and reveal the limits of governance. By considering these limits in mediation with Aboriginal Australian people, I argue that the susceptibility of mediator selves contains prospects for mitigating and transforming the very operations of power occurring through conflict resolution. This suggests options for expanded critical thinking about power relations operating through informal processes, and for cultivating a susceptible sensibility to mitigate liberal governance and more ethically respond to difference through conflict resolution

Satellite and in situ observations for advancing global Earth surface modelling: a review

In this paper, we review the use of satellite-based remote sensing in combination with in situ data to inform Earth surface modelling. This involves verification and optimization methods that can handle both random and systematic errors and result in effective model improvement for both surface monitoring and prediction applications. The reasons for diverse remote sensing data and products include (i) their complementary areal and temporal coverage, (ii) their diverse and covariant information content, and (iii) their ability to complement in situ observations, which are often sparse and only locally representative. To improve our understanding of the complex behavior of the Earth system at the surface and sub-surface, we need large volumes of data from high-resolution modelling and remote sensing, since the Earth surface exhibits a high degree of heterogeneity and discontinuities in space and time. The spatial and temporal variability of the biosphere, hydrosphere, cryosphere and anthroposphere calls for an increased use of Earth observation (EO) data attaining volumes previously considered prohibitive. We review data availability and discuss recent examples where satellite remote sensing is used to infer observable surface quantities directly or indirectly, with particular emphasis on key parameters necessary for weather and climate prediction. Coordinated high-resolution remote-sensing and modelling/assimilation capabilities for the Earth surface are required to support an international application-focused effort

Challenges of operational river forecasting

Skillful and timely streamflow forecasts are critically important to water managers and emergency protection services. To provide these forecasts, hydrologists must predict the behavior of complex coupled human–natural systems using incomplete and uncertain information and imperfect models. Moreover, operational predictions often integrate anecdotal information and unmodeled factors. Forecasting agencies face four key challenges: 1) making the most of available data, 2) making accurate predictions using models, 3) turning hydrometeorological forecasts into effective warnings, and 4) administering an operational service. Each challenge presents a variety of research opportunities, including the development of automated quality-control algorithms for the myriad of data used in operational streamflow forecasts, data assimilation, and ensemble forecasting techniques that allow for forecaster input, methods for using human-generated weather forecasts quantitatively, and quantification of human interference in the hydrologic cycle. Furthermore, much can be done to improve the communication of probabilistic forecasts and to design a forecasting paradigm that effectively combines increasingly sophisticated forecasting technology with subjective forecaster expertise. These areas are described in detail to share a real-world perspective and focus for ongoing research endeavors