Geochemistry of Thermal Waters of Continental Margin of Far East of Russia

Studied waters belong to warm （T=30-50℃）, alkaline （pH=8.9-9.3）, low mineralized （TDS〈235 mg/l） Na-HCO3 or Na-SO4-HCO3 thermal waters with high content of SiO2 （up to 81 mg/1） and F （up to 3.9 mg/l）, occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt. Low 3He concentration as well as N2/O2 and N2/Ar ratios exclude influence of deep mantle fluid. New rare earth element data constrain our understanding of water-rock interaction occurring in the water source region. Meteoric origin of waters is proved by stable isotope values varying from -71%o to -136.1‰ and from -10.8‰ to -18.8%o for δ^2H and δ^18O respectively. REE patterns reflect high pH, resultfing from water-rock interaction and oxidative conditions. Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1℃ and 82.2-125.8℃ respectively. Presence of deep faults both with abnormal thermal gradient （-45- 50 K/km） define unique geochemical shape of thermal waters of Sikhote-Alin, area, where no present volcanic activity is registered.

Threats to the Thermal Mineralized Waters Used for Therapeutic Purposes in Jordan

Although Jordan is a country with very limited water resources, the country is rich in its thermal mineralized water possessing curative properties, historically used for the therapy of a variety of ailments. Due to the country’s increasing water demand resulting from population growth, urbanization, and industrialization, extractions from the groundwater sources feeding the thermal mineralized springs has started to affect negatively the discharged quantities from the springs. In addition, urbanization, mining activities, over-exploited groundwater resources in general and severe drop in the level of the Dead Sea are leading to declining discharge of springs in general, and thermal mineralized in special, deteriorating water quality and contamination by human activities. In this article, the current quantitative and qualitative situation of the thermal mineralized springs is given and the threats to their discharges and quantities are discussed. In addition, some water policy changes and measures are suggested to conserve these therapeutic waters for the use of generations to come and to alleviate their depletion and quality deterioration on the social and economic state of Jordan.

Jonzac Thermal Spring Water Reinforces Skin Barrier Function of Human Skin and Presents a Soothing and Regenerating Effect

The skin is a formidable physical and biological barrier which communicates continuously with the outside of the body. And the stratum corneum, the outermost layer of human epidermis, plays a central role in the interaction between the cutaneous tissue and the external environment. The horny layer, and more generally the whole skin layers, avoid the penetration of harmful exogenous agents, produce molecules named anti-microbial peptides which impact the composition of the cutaneous microbiota, regulate the internal corporal temperature, avoid the water loss from the inside of the body and constitute an incredible efficient anti-oxidant network. Nevertheless, nowadays, the skin is more and more solicited by the different elements of the cutaneous exposome, including atmospheric pollution and solar radiations, which can cause a dramatic acceleration of the skin ageing process. As a consequence, due to the multifunctional protective role of the skin, during the recent decade the cosmetic industry invested massively in the development of new raw materials and end-products (dermo-cosmetics) able to preserve an optimal state of the skin regarding the external environment. Based on their physical-chemical properties thermal spring waters, which are extremely rich in inorganics ions, are interesting and powerful candidates to be part, as integral component, of new efficient dermo-cosmetic formulations dedicated to protect the skin from the external stimuli. The aim of the present work was to investigate and characterize the activity of Jonzac thermal spring water on the skin. Using different models, we proved for the first time that Jonzac thermal spring water reinforces the barrier function of the skin by modulating the expression of key markers including filaggrin and human beta defensin 2 on ex vivo human skin. The ex vivo and in vivo hydration activity, by Raman spectroscopy and corneometry respectively, has been also demonstrated. We have also shown that Jonzac thermal spring water ameliorates significantly the cutaneous microrelief in vivo. To conclude, we characterize the soothing effect of Jonzac thermal spring water by the analysis of histamine release in Substance P treated skin explants and by measuring the redness of the skin following UV exposure of the skin in vivo. We observed that both parameters decreased following a preventive treatment of the skin with Jonzac thermal spring water. Taken together our results indicate that Jonzac thermal spring water is a promising and powerful dermo-cosmetic which can be used to preserve an optimal state of the cutaneous tissue.

Environmental Drivers of Temporal and Spatial Fluctuations of Mesozooplankton Community in Daya Bay, Northern South China Sea

The response of zooplankton to the ecological environment in Daya Bay is unclear under the influence of both climate changes and anthropogenic activities on a seasonal to inter-annual scale.Based on monthly surveys and historical data,we found the zooplankton community had changed temporally and spatially.A total of 134 species was recorded during the study,and copepods dominated numerically in terms of diversity and abundance.Both copepods and cladocerans were the main contributors to zooplankton abundance.The community structure of zooplankton was temporally classified into the warm and cold groups,and spatially into the three groups located in the marine cage-culture area(MCCA),the outflow of nuclear power plants(ONPP)and unpolluted waters(UPW).The zooplankton was characterized by low biomass(dry weight),high diversity and abundance in the warm period in contrast to that in the cold period.Compared with the other two groups,the MCCA group of zooplankton showed high abundance,low diversity and biomass.Variations in dominant species were closely related to temperature,salinity and chlorophyll a concentration.Species diversity and dry weight decreased in comparison with 30 years ago,while zooplankton abundance increased.The seasonal variation in zooplankton was affected mainly by temperature that was controlled by monsoon,while the spatial difference in the community structure was probably due to eutrophication in the MCCA and thermal water discharge from ONPP.The zooplankton community is undergoing great changes with the tendency of miniaturization and gelatinization in recent 30 years in Daya Bay.

Numerical modeling and simulation of PEM fuel cells: Progress and perspective

This paper provides a comprehensive review on the research and development in multi-scale numerical modeling and simulation of PEM fuel cells. An overview of recent progress in PEM fuel cell modeling has been provided. Fundamental transport phenomena in PEM fuel cells and the corresponding mathematical formulation of macroscale models are analyzed. Various important issues in PEM fuel cell modeling and simulation are examined in detail, including fluid flow and species transport, electron and proton transport, heat transfer and thermal management, liquid water transport and water management, transient response behaviors, and cold-start processes. Key areas for further improvements have also been discussed.

Towards full predictions of temperature dynamics in McNary Dam forebay using OpenFOAM

Hydroelectric facilities impact water temperature; low velocities in a reservoir increase residence time and enhance heat exchange in surface layers. In this study, an unsteady three-dimensional model was developed to predict the temperatm＇e dynamics in the McNary Dam forebay. The model is based on the open-source code OpenFOAM. RANS equations with the Boussinesq approximation were used to solve the flow field. A： realizable k-ε model that accounts for the production of wind turbulence was developed. Solar radiation and convective heat transfer at the free surface were included. The result of the model was compared with the field data collected on August 18, 2004. Changes in diurnal stratification were adequately predicted by the model. Observed vertical and lateral temperature distributions were accurately captured. Results indicate that the model can be used as a numerical tool to assess structural and operational alternatives to reduce the forebay temperature.

Physico-Chemical Characteristics of Gushing Water Aquifers in the Coastal Sedimentary Basin of Benin (West Africa)

The coastal sedimentary basin in southern Benin consists of monoclinal layers divided into two plateau zones (North and South) which are separated by a longitudinal depression ESE-WNW. The valleys of the main N-S-oriented rivers (Ouémé, Couffo and Mono) set the bondaries of the different plateau of the BSC (Coastal Sedimentary Basin). The present study, based on geology, hydrochemistry, temperature and log data available on boreholes, makes a physico-chemical characterization of the waters of the gushing aquifers of the coastal sedimentary basin of Benin. The gushing water boreholes are shared between the valleys of the main rivers of the BSC. Some of these boreholes are thermal with a water temperature between 38 and 69 degrees Celsius. The hydrogeological correlations established in the BSC in accordance to the North- South direction in the valleys of the main streams (Couffo and Ouémé) reveal that the captured aquifers are sands, marls and limestones that respond either in major discordance (northern zone) or above the sedimentation gaps (southern zone). Chemical analyses have shown that gushing thermal waters are mineralized in the south with a neutral to basic pH and are highly concentrated with bicarbonate, calcium and magnesium ions. In the North, on the other hand, thermal waters are acidic with a pH ranging from 4.8 to 5.9. The acidic nature of the northern waters is influenced by the crystalline base while the southern neutral to basic waters are influenced by the lithological nature (limestone and marl) of the aquifer. The random distribution of thermal water boreholes in the valleys of the main BSC streams is believed to be related to tectonic events.

A systematic review of system modeling and control strategy of proton exchange membrane fuel cell

The proton exchange membrane fuel cell,as a novel energy device,exhibits a wide array of potential applications.This paper offers a comprehensive review and discussion of modeling and control strategies for fuel cell systems.It commences with a concise introduction to the structure and principles of fuel cells.Subsequently,it outlines modeling approaches for various fuel cell subsystems,encompassing the fuel cell stack,air supply system,hydrogen supply system,thermal management system,and water management system.Following this,it conducts a comparative analysis and discussion of prevalent control strategies for the aforementioned subsystems.Lastly,the paper outlines future research trends and directions in the modeling and control strategies of fuel cells.The aim of this paper is to provide ideas and inspirations for the design and management of membrane fuel cell systems from control aspects.

Progress in the proton exchange membrane fuel cells(PEMFCs)water/thermal management:From theory to the current challenges and real-time fault diagnosis methods

Proton Exchange Membrane Fuel Cells(PEMFCs)are known as a promising alternative for internal combustion engines(ICE)to reduce pollution.Recent progress of PEMFCs is heading towards achieving higher power densities,reducing the refueling time,and decreasing the degradations,to facilitate the commercialization of hydrogen mobility.Model-assisted stack component development,diagnosis,and management are essential to ensure improved stack design and operation for tackling the existing implementation challenges of PEMFCs.Past reviews usually touched on a specific aspect,which can hardly provide the readers a complete picture of the key challenges and advances in water management.This paper aims at delivering a comprehensive source to review,from both experimental,analytical,and numerical viewpoints,the key operational challenges,and solutions of the stack to improve water/thermal management and cold start.In addition to presenting the fundamental theory to develop an analytical model,the recent advances in the flow field design,nanofluid coolants,and cold-start methods.Furthermore,the impacts of microstructural properties and the design of the porous layers on the water/thermal management are described.

Flux Globalization BasedWell-Balanced Path-Conservative Central-Upwind Scheme for the Thermal Rotating ShallowWater Equations

We present an extension of the flux globalization based well-balanced pathconservative central-upwind scheme to the one-and two-dimensional thermal rotating shallow water equations.The scheme is well-balanced in the sense that it can exactly preserve a variety of physically relevant steady states.In the one-dimensional case,it can preserve different“lake-at-rest”equilibria,thermo-geostrophic equilibria,as well as general moving-water steady states.In the two-dimensional case,preserving general moving-water steady states is difficult,and to the best of our knowledge,none of existing schemes can achieve this ultimate goal.The proposed scheme can exactly preserve the x-and y-directional jets in the rotational frame as well as certain genuinely two-dimensional equilibria.Furthermore,our approach employs a path-conservative technique for discretizing nonconservative product terms,which are incorporated into the global fluxes.This allows the developed scheme to exactly preserve some of the discontinuous steady states as well.We provide a number of numerical examples to demonstrate the advantages of the proposed scheme over some alternative finitevolume methods.

Physicochemical regeneration of high silica zeolite Y used to clean-up water polluted with sulfonamide antibiotics

High silica zeolite Y has been positively evaluated to clean-up water polluted with sulfonamides, an antibiotic family which is known to be involved in the antibiotic resistance evolution. To define possible strategies for the exhausted zeolite regeneration,the efficacy of some chemico-physical treatments on the zeolite loaded with four different sulfonamides was evaluated. The evolution of photolysis, Fenton-like reaction, thermal treatments, and solvent extractions and the occurrence in the zeolite pores of organic residues eventually entrapped was elucidated by a combined thermogravimetric（TGA–DTA）, diffractometric（XRPD）, and spectroscopic（FT-IR） approach. The chemical processes were not able to remove the organic guest from zeolite pores and a limited transformation on embedded molecules was observed. On the contrary, both thermal treatment and solvent extraction succeeded in the regeneration of the zeolite loaded from deionized and natural fresh water. The recyclability of regenerated zeolite was evaluated over several adsorption/regeneration cycles, due to the treatment efficacy and its stability as well as the ability to regain the structural features of the unloaded material.