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Multiple Hearth Furnace (MHF) is a promising technology for biomass torrefaction. However, experimental data from large-scale units are missing to understand process parameters and biomass composition effects on torrefaction yields. In the present study, a deciduous wood (oak) and an agricultural biomass (olive stones) were torrefied in a semi-industrial multiple hearth furnace at 250 and 300 °C for a mean residence time of 40 min. Permanent gases and biomass streams entering and exiting the furnace were quantified on-line and analyzed. Steady state regime was reached and main torrefaction yields were replicable along torrefaction tests. Large axial dispersion of particles in this MHF was inferred by residence time distribution measurements (8 < Pe < 16). As expected, for both olive stones and oak, the solid mass loss and the carbon content of the torrefied biomass increase when increasing the process temperature. Moisture content of raw biomass has a determining impact on torrefaction severity. At 250 °C, dry mass losses of two oak batches having a moisture content of 12.6 and 27.4 %w are respectively equal to 11 and 4 %w-db. Condensable gases were identified by gas chromatography coupled to mass spectrometry (GC-MS). Most of the species detected are the same as those reported in the literature but some additional ones are present such as polycyclic aromatic hydrocarbons, benzene and toluene due to hot spots near burner flames. Temperature distribution along the MHF is not fully homogeneous and can diverge from 20 to 40 °C from the temperature set point.

In continuous biomass torrefaction plants, the products' yields, composition and homogeneity highly depend on the residence time of particles. A characterization of particle residence time distribution (RTD) was therefore carried out in an industrial-scale multiple hearth furnace on poplar wood chips using radio frequency identification tracers. The effects of operating conditions, namely, mass flow rate of biomass, shaft speed of the rabbling system and interdental length on the RTD were studied. The increase of shaft speed and mass flow rate reduces particles’ mean residence time. Lowering the length between two successive teeth also increases the bed speed. Uncontrollable biomass accumulation (also called “bulldozing”) was observed during several tests. This phenomenon is favored by a high mass flow rate of resources, a small interdental length between the teeth and a low shaft speed. RTD measurements were compared to the axial dispersion model. For all tests, the Peclet number is ranging between 20 and 62, indicating that the multiple hearth furnace cannot be modelled as an ideal plug flow reactor.

Our knowledge about the effects of perceived emotional support on PTSD, anxiety and depressive symptoms after serious threat and violence is primarily based on post-event studies. Very little is known about the extent to which (1) victims lacking pre-event emotional support are more at risk of post-event symptoms and lack of post-event support than victims with pre-event emotional support, and (2) victims with pre-event emotional support and victims lacking emotional support are more at risk of post-event anxiety and depressive symptoms than nonvictims with similar pre-event support levels. For this purpose, we conducted a 2-wave prospective study (VICTIMS) using the Dutch population-based longitudinal LISS panel. Multivariate logistic regression analyses were conducted, controlling for pre-event demographics, symptoms, and physical, work-related and financial problems. As hypothesized, victims (Nvictims total = 187) lacking pre-event support more often had high post-event PTSD, anxiety and depressive symptoms than victims with pre-event support. No significant differences were found between victims and nonvictims with pre-event emotional support (Nnonvictims total = 2,828, not exposed to any event). Since victims and nonvictims with pre-event support did not differ in post-event symptoms and support, the findings offer strong evidence for the buffering hypothesis of emotional support.

We present an overview of state-of-the-art chemistry–climate and chemistry transport models that are used within phase 1 of the Chemistry–Climate Model Initiative (CCMI-1). The CCMI aims to conduct a detailed evaluation of participating models using process-oriented diagnostics derived from observations in order to gain confidence in the models' projections of the stratospheric ozone layer, tropospheric composition, air quality, where applicable global climate change, and the interactions between them. Interpretation of these diagnostics requires detailed knowledge of the radiative, chemical, dynamical, and physical processes incorporated in the models. Also an understanding of the degree to which CCMI-1 recommendations for simulations have been followed is necessary to understand model responses to anthropogenic and natural forcing and also to explain inter-model differences. This becomes even more important given the ongoing development and the ever-growing complexity of these models. This paper also provides an overview of the available CCMI-1 simulations with the aim of informing CCMI data users.

Contains fulltext : 170731.pdf (publisher's version ) (Closed access), Motivated by the ever-growing revenue of remittances from overseas Filipino workers (OFWs), the government of the Philippines praises economic migrants as the bagong bayani (the "new heroes of the nation") who enjoy something of celebrity status including reverential treatment from their civilian peers. However, neglected in this honourable denomination is the uncomfortable relationship between migrants' "heroism" and the repercussions for those who do not migrate. The government's "national script" creates a paradox by challenging the comfort zone of the traditional division of labour without taking recognition of the cultural challenges migration produces, taking the form of reprehensive feedback within transnational relationships between migrants and their spouses, but also with society at large, notably when migration produces behaviour considered deviant from culture's general social norms. Thus men who take on the responsibilities of their wives are stigmatized, and women who stay behind devote themselves as fulltime housewives, even if this reduces their income prospects. The question remains how remittances influence transnational relationships, and whether it exacerbates a situation of dependency, or rather promotes opportunities for more liberal labour division schemes within transnational households. From our research in Cebu City, we find that frictional zones are formed by both factors, and that societal expectations of gendered behaviour and the "culture of migration" that emerged in conjunction with the New Heroes paradigm are ultimately the primary reasons for this.

Contains fulltext : 170757.pdf (publisher's version ) (Closed access)

Contains fulltext : 170731.pdf (publisher's version ) (Closed access), Motivated by the ever-growing revenue of remittances from overseas Filipino workers (OFWs), the government of the Philippines praises economic migrants as the bagong bayani (the "new heroes of the nation") who enjoy something of celebrity status including reverential treatment from their civilian peers. However, neglected in this honourable denomination is the uncomfortable relationship between migrants' "heroism" and the repercussions for those who do not migrate. The government's "national script" creates a paradox by challenging the comfort zone of the traditional division of labour without taking recognition of the cultural challenges migration produces, taking the form of reprehensive feedback within transnational relationships between migrants and their spouses, but also with society at large, notably when migration produces behaviour considered deviant from culture's general social norms. Thus men who take on the responsibilities of their wives are stigmatized, and women who stay behind devote themselves as fulltime housewives, even if this reduces their income prospects. The question remains how remittances influence transnational relationships, and whether it exacerbates a situation of dependency, or rather promotes opportunities for more liberal labour division schemes within transnational households. From our research in Cebu City, we find that frictional zones are formed by both factors, and that societal expectations of gendered behaviour and the "culture of migration" that emerged in conjunction with the New Heroes paradigm are ultimately the primary reasons for this.

Contains fulltext : 170731.pdf (publisher's version ) (Closed access), Motivated by the ever-growing revenue of remittances from overseas Filipino workers (OFWs), the government of the Philippines praises economic migrants as the bagong bayani (the "new heroes of the nation") who enjoy something of celebrity status including reverential treatment from their civilian peers. However, neglected in this honourable denomination is the uncomfortable relationship between migrants' "heroism" and the repercussions for those who do not migrate. The government's "national script" creates a paradox by challenging the comfort zone of the traditional division of labour without taking recognition of the cultural challenges migration produces, taking the form of reprehensive feedback within transnational relationships between migrants and their spouses, but also with society at large, notably when migration produces behaviour considered deviant from culture's general social norms. Thus men who take on the responsibilities of their wives are stigmatized, and women who stay behind devote themselves as fulltime housewives, even if this reduces their income prospects. The question remains how remittances influence transnational relationships, and whether it exacerbates a situation of dependency, or rather promotes opportunities for more liberal labour division schemes within transnational households. From our research in Cebu City, we find that frictional zones are formed by both factors, and that societal expectations of gendered behaviour and the "culture of migration" that emerged in conjunction with the New Heroes paradigm are ultimately the primary reasons for this.

Contains fulltext : 170731.pdf (publisher's version ) (Closed access), Motivated by the ever-growing revenue of remittances from overseas Filipino workers (OFWs), the government of the Philippines praises economic migrants as the bagong bayani (the "new heroes of the nation") who enjoy something of celebrity status including reverential treatment from their civilian peers. However, neglected in this honourable denomination is the uncomfortable relationship between migrants' "heroism" and the repercussions for those who do not migrate. The government's "national script" creates a paradox by challenging the comfort zone of the traditional division of labour without taking recognition of the cultural challenges migration produces, taking the form of reprehensive feedback within transnational relationships between migrants and their spouses, but also with society at large, notably when migration produces behaviour considered deviant from culture's general social norms. Thus men who take on the responsibilities of their wives are stigmatized, and women who stay behind devote themselves as fulltime housewives, even if this reduces their income prospects. The question remains how remittances influence transnational relationships, and whether it exacerbates a situation of dependency, or rather promotes opportunities for more liberal labour division schemes within transnational households. From our research in Cebu City, we find that frictional zones are formed by both factors, and that societal expectations of gendered behaviour and the "culture of migration" that emerged in conjunction with the New Heroes paradigm are ultimately the primary reasons for this.

Contains fulltext : 170757.pdf (publisher's version ) (Closed access)

Contains fulltext : 170731.pdf (Publisher’s version ) (Closed access), Motivated by the ever-growing revenue of remittances from overseas Filipino workers (OFWs), the government of the Philippines praises economic migrants as the bagong bayani (the "new heroes of the nation") who enjoy something of celebrity status including reverential treatment from their civilian peers. However, neglected in this honourable denomination is the uncomfortable relationship between migrants' "heroism" and the repercussions for those who do not migrate. The government's "national script" creates a paradox by challenging the comfort zone of the traditional division of labour without taking recognition of the cultural challenges migration produces, taking the form of reprehensive feedback within transnational relationships between migrants and their spouses, but also with society at large, notably when migration produces behaviour considered deviant from culture's general social norms. Thus men who take on the responsibilities of their wives are stigmatized, and women who stay behind devote themselves as fulltime housewives, even if this reduces their income prospects. The question remains how remittances influence transnational relationships, and whether it exacerbates a situation of dependency, or rather promotes opportunities for more liberal labour division schemes within transnational households. From our research in Cebu City, we find that frictional zones are formed by both factors, and that societal expectations of gendered behaviour and the "culture of migration" that emerged in conjunction with the New Heroes paradigm are ultimately the primary reasons for this.

Contains fulltext : 170757.pdf (Publisher’s version ) (Closed access)

The delta region between Rotterdam and Antwerp is a prime example of an area where spatial developments face increasing complexity. Local initiatives for developing urban expansions, recreation areas, nature and industrial complexes must harmonize with measures such as adequate flood protection, sufficient freshwater supply, restoration of ecosystems and large-scale infrastructure over the long term. This complexity demans a new approach to spatial planning and design. This book is the result of a research project that aimed to develop such a new planning practice. The research was carried out in collaboration by a consortium of universities, centres of expertise, and engineering and design firms. The research conceived of the Southwest Delta of the Netherlands as a laboratory for the new approach, which has nonetheless also proven relevant to other regions dealing with a similar level of complexity.

There is extensive experience in adaptive management of exposed sandy coastlines through sand nourishment for coastal protection. However, in complex estuarine systems, coastlines are often shortened through damming estuaries to achieve desired safety levels. The Dutch Deltaworks illustrate that this approach disrupts natural sediment fluxes and harms ecosystem health, which negatively affects derived ecosystem services, such as freshwater availability and mussel and oyster farming. This heavily impacts local communities and thus requires additional maintenance and management efforts. Nevertheless, the discussion on coastline shortening keeps surfacing when dealing with complex coastal management issues throughout the world. Although adaptive delta management accompanied by innovative approaches that integrate coastal safety with ecosystem services is gaining popularity, it is not yet common practice to include adaptive pathways, a system-based view and ecosystem knowledge into coastal management projects. Here, we provide a first attempt to integrate ecosystem-based flood risk reduction measures in the standard suite of flood risk management solutions, ranging from structural to non-structural. Additionally, for dealing with the dynamic and more unpredictable nature of ecosystems, we suggest the adaptive delta management approach that consists of flexible measures, measurable targets, monitoring and intervention, as a framework for embedding ecosystem-based alternatives for flood risk mitigation in the daily practice of engineers and coastal planners.

There is extensive experience in adaptive management of exposed sandy coastlines through sand nourishment for coastal protection. However, in complex estuarine systems, coastlines are often shortened through damming estuaries to achieve desired safety levels. The Dutch Deltaworks illustrate that this approach disrupts natural sediment fluxes and harms ecosystem health, which negatively affects derived ecosystem services, such as freshwater availability and mussel and oyster farming. This heavily impacts local communities and thus requires additional maintenance and management efforts. Nevertheless, the discussion on coastline shortening keeps surfacing when dealing with complex coastal management issues throughout the world. Although adaptive delta management accompanied by innovative approaches that integrate coastal safety with ecosystem services is gaining popularity, it is not yet common practice to include adaptive pathways, a system-based view and ecosystem knowledge into coastal management projects. Here, we provide a first attempt to integrate ecosystem-based flood risk reduction measures in the standard suite of flood risk management solutions, ranging from structural to non-structural. Additionally, for dealing with the dynamic and more unpredictable nature of ecosystems, we suggest the adaptive delta management approach that consists of flexible measures, measurable targets, monitoring and intervention, as a framework for embedding ecosystem-based alternatives for flood risk mitigation in the daily practice of engineers and coastal planners.

Worldwide, deltas host dense populations and are important centres of agricultural and industrial production, and economic activity. Many deltas are areas of great ecological importance as well, featuring wetlands of high and unique biodiversity. Deltas are vulnerable to changes by natural forces and human activities. Major drivers of change are population growth, economic development, climate change and subsidence.

Worldwide, deltas host dense populations and are important centres of agricultural and industrial production, and economic activity. Many deltas are areas of great ecological importance as well, featuring wetlands of high and unique biodiversity. Deltas are vulnerable to changes by natural forces and human activities. Major drivers of change are population growth, economic development, climate change and subsidence.

Deltas are dynamic landforms at the boundary of land and sea, involving intricate mazes of rivers and small waterways, wetlands, estuaries and coastal barrier islands. They are home to over half a billion people. Deltas are also home to rich ecosystems, such as mangroves and marshes. They are economic hotspots, supporting much of the world’s fisheries, forest products, and extensive agriculture. Yet, delta systems are under threat from sea-level rise, cyclones, river flooding, storm surges, rapid urbanization, agricultural over-use and pollution, salinization, sediment starvation, coastal erosion, and natural and man-made subsidence. One of the missions of the Delta Alliance is to support the development and proliferation of new approaches in delta management through research, exchange of best practices and outreach of concepts and ideas. This report provides an overview of new approaches emerging in several deltas that can be labelled under the heading of Adaptive Delta Management. Adaptive management can be defined as a structured, iterative process of robust decision making in the face of uncertainty, with an aim to reduce uncertainty over time via system monitoring. Applying adaptive management to deltas is relatively new and one of the first explicit uses is by the Dutch Delta Program. The Dutch Delta Program formulates Adaptive Delta Management (ADM) as phased decision-making that takes uncertain long-term developments into account explicitly and in with transparency towards society. Adaptive delta management encourages an integrated and flexible approach to land and water management with to aim to reduce vulnerability limit the risk of over- or underinvestment in future challenges such as flood risk management and freshwater supplies. This report shows that ADM is developing rapidly into a fascinating new type of decision making under an uncertain future. The reasons for using the new approach are convincing, the theoretical foundation is growing and the resu

We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper presents an overview of the different model components and explains how they were coupled and used to simulate historical climate changes over the past 150 years and different scenarios of future climate change. A single version of the IPSL-CM5 model (IPSL-CM5A-LR) was used to provide climate projections associated with different socio-economic scenarios, including the different Representative Concentration Pathways considered by CMIP5 and several scenarios from the Special Report on Emission Scenarios considered by CMIP3. Results suggest that the magnitude of global warming projections primarily depends on the socio-economic scenario considered, that there is potential for an aggressive mitigation policy to limit global warming to about two degrees, and that the behavior of some components of the climate system such as the Arctic sea ice and the Atlantic Meridional Overturning Circulation may change drastically by the end of the twenty-first century in the case of a no climate policy scenario. Although the magnitude of regional temperature and precipitation changes depends fairly linearly on the magnitude of the projected global warming (and thus on the scenario considered), the geographical pattern of these changes i

We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper presents an overview of the different model components and explains how they were coupled and used to simulate historical climate changes over the past 150 years and different scenarios of future climate change. A single version of the IPSL-CM5 model (IPSL-CM5A-LR) was used to provide climate projections associated with different socio-economic scenarios, including the different Representative Concentration Pathways considered by CMIP5 and several scenarios from the Special Report on Emission Scenarios considered by CMIP3. Results suggest that the magnitude of global warming projections primarily depends on the socio-economic scenario considered, that there is potential for an aggressive mitigation policy to limit global warming to about two degrees, and that the behavior of some components of the climate system such as the Arctic sea ice and the Atlantic Meridional Overturning Circulation may change drastically by the end of the twenty-first century in the case of a no climate policy scenario. Although the magnitude of regional temperature and precipitation changes depends fairly linearly on the magnitude of the projected global warming (and thus on the scenario considered), the geographical pattern of these changes i

We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper presents an overview of the different model components and explains how they were coupled and used to simulate historical climate changes over the past 150 years and different scenarios of future climate change. A single version of the IPSL-CM5 model (IPSL-CM5A-LR) was used to provide climate projections associated with different socio-economic scenarios, including the different Representative Concentration Pathways considered by CMIP5 and several scenarios from the Special Report on Emission Scenarios considered by CMIP3. Results suggest that the magnitude of global warming projections primarily depends on the socio-economic scenario considered, that there is potential for an aggressive mitigation policy to limit global warming to about two degrees, and that the behavior of some components of the climate system such as the Arctic sea ice and the Atlantic Meridional Overturning Circulation may change drastically by the end of the twenty-first century in the case of a no climate policy scenario. Although the magnitude of regional temperature and precipitation changes depends fairly linearly on the magnitude of the projected global warming (and thus on the scenario considered), the geographical pattern of these changes i

We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper presents an overview of the different model components and explains how they were coupled and used to simulate historical climate changes over the past 150 years and different scenarios of future climate change. A single version of the IPSL-CM5 model (IPSL-CM5A-LR) was used to provide climate projections associated with different socio-economic scenarios, including the different Representative Concentration Pathways considered by CMIP5 and several scenarios from the Special Report on Emission Scenarios considered by CMIP3. Results suggest that the magnitude of global warming projections primarily depends on the socio-economic scenario considered, that there is potential for an aggressive mitigation policy to limit global warming to about two degrees, and that the behavior of some components of the climate system such as the Arctic sea ice and the Atlantic Meridional Overturning Circulation may change drastically by the end of the twenty-first century in the case of a no climate policy scenario. Although the magnitude of regional temperature and precipitation changes depends fairly linearly on the magnitude of the projected global warming (and thus on the scenario considered), the geographical pattern of these changes i

The international research project RECONCILE has addressed central questions regarding polar ozone depletion, with the objective to quantify some of the most relevant yet still uncertain physical and chemical processes and thereby improve prognostic modelling capabilities to realistically predict the response of the ozone layer to climate change. This overview paper outlines the scope and the general approach of RECONCILE, and it provides a summary of observations and modelling in 2010 and 2011 that have generated an in many respects unprecedented dataset to study processes in the Arctic winter stratosphere. Principally, it summarises important outcomes of RECONCILE including (i) better constraints and enhanced consistency on the set of parameters governing catalytic ozone destruction cycles, (ii) a better understanding of the role of cold binary aerosols in heterogeneous chlorine activation, (iii) an improved scheme of polar stratospheric cloud (PSC) processes that includes heterogeneous nucleation of nitric acid trihydrate (NAT) and ice on non-volatile background aerosol leading to better model parameterisations with respect to denitrification, and (iv) long transient simulations with a chemistry-climate model (CCM) updated based on the results of RECONCILE that better reproduce past ozone trends in Antarctica and are deemed to produce more reliable predictions of future ozone trends. The process studies and the global simulations conducted in RECONCILE show that in the Arctic, ozone depletion uncertainties in the chemical and microphysical processes are now clearly smaller than the sensitivity to dynamic variability.

This discussion paper describes an integrated framework for delta assessment, the need for specific strategies for deltas, especially as it relates to integrated water resources management, and taking into account the increasing interest for the institutional, socio-economic, financial and awareness-raising aspects.

We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper presents an overview of the different model components and explains how they were coupled and used to simulate historical climate changes over the past 150 years and different scenarios of future climate change. A single version of the IPSL-CM5 model (IPSL-CM5A-LR) was used to provide climate projections associated with different socio-economic scenarios, including the different Representative Concentration Pathways considered by CMIP5 and several scenarios from the Special Report on Emission Scenarios considered by CMIP3. Results suggest that the magnitude of global warming projections primarily depends on the socio-economic scenario considered, that there is potential for an aggressive mitigation policy to limit global warming to about two degrees, and that the behavior of some components of the climate system such as the Arctic sea ice and the Atlantic Meridional Overturning Circulation may change drastically by the end of the twenty-first century in the case of a no climate policy scenario. Although the magnitude of regional temperature and precipitation changes depends fairly linearly on the magnitude of the projected global warming (and thus on the scenario considered), the geographical pattern of these changes i

The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous numerical simulations, a recirculating cell inside the meniscus appears when the injected liquid flow rate is reduced. Thus, as the flow rate is reduced not only the average residence time of particles in the meniscus becomes longer, but the appearance of a recirculation cell provides a natural platform for the efficient micro-mixing of different species before they are ejected through the issuing jet. The numerical results were confirmed with experimental visualization of the flow inside the meniscus using a dyed liquid. However, when the viscosity of the liquid is increased the recirculating cell disappears. In this case, viscous stresses organize the streamlines and direct the flow to the meniscus tip, which prevents the recirculating cell from being formed even for very small injected rate of liquid flow.

The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous numerical simulations, a recirculating cell inside the meniscus appears when the injected liquid flow rate is reduced. Thus, as the flow rate is reduced not only the average residence time of particles in the meniscus becomes longer, but the appearance of a recirculation cell provides a natural platform for the efficient micro-mixing of different species before they are ejected through the issuing jet. The numerical results were confirmed with experimental visualization of the flow inside the meniscus using a dyed liquid. However, when the viscosity of the liquid is increased the recirculating cell disappears. In this case, viscous stresses organize the streamlines and direct the flow to the meniscus tip, which prevents the recirculating cell from being formed even for very small injected rate of liquid flow.

Hydraulic Engineering, Civil Engineering and Geosciences

Hydraulic Engineering, Civil Engineering and Geosciences

The environment in the Yellow River Delta (YRD) is under stress from large socio-economic pressures, leading to air, soil and water pollution. A Sino-Dutch project the Sustainable Development YRD project (1995 – 1997) was undertaken with the principle goal of contributing to the sustainable, long-term development of the Yellow River Delta. Objectives and criteria for sustainable development were defined. One of the main project challenges was to show how to use the limited fresh water resources in a sustainable way. This was undertaken using integrated and analytical tools in which future developments and strategies were systematically analysed. Such an approach provides a strong incentive to begin communication and develop mutual understanding between the different responsible authorities and stakeholders., Hydraulic Engineering, Civil Engineering and Geosciences

The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous numerical simulations, a recirculating cell inside the meniscus appears when the injected liquid flow rate is reduced. Thus, as the flow rate is reduced not only the average residence time of particles in the meniscus becomes longer, but the appearance of a recirculation cell provides a natural platform for the efficient micro-mixing of different species before they are ejected through the issuing jet. The numerical results were confirmed with experimental visualization of the flow inside the meniscus using a dyed liquid. However, when the viscosity of the liquid is increased the recirculating cell disappears. In this case, viscous stresses organize the streamlines and direct the flow to the meniscus tip, which prevents the recirculating cell from being formed even for very small injected rate of liquid flow.

The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous numerical simulations, a recirculating cell inside the meniscus appears when the injected liquid flow rate is reduced. Thus, as the flow rate is reduced not only the average residence time of particles in the meniscus becomes longer, but the appearance of a recirculation cell provides a natural platform for the efficient micro-mixing of different species before they are ejected through the issuing jet. The numerical results were confirmed with experimental visualization of the flow inside the meniscus using a dyed liquid. However, when the viscosity of the liquid is increased the recirculating cell disappears. In this case, viscous stresses organize the streamlines and direct the flow to the meniscus tip, which prevents the recirculating cell from being formed even for very small injected rate of liquid flow.

The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous numerical simulations, a recirculating cell inside the meniscus appears when the injected liquid flow rate is reduced. Thus, as the flow rate is reduced not only the average residence time of particles in the meniscus becomes longer, but the appearance of a recirculation cell provides a natural platform for the efficient micro-mixing of different species before they are ejected through the issuing jet. The numerical results were confirmed with experimental visualization of the flow inside the meniscus using a dyed liquid. However, when the viscosity of the liquid is increased the recirculating cell disappears. In this case, viscous stresses organize the streamlines and direct the flow to the meniscus tip, which prevents the recirculating cell from being formed even for very small injected rate of liquid flow.

Hydraulic Engineering, Civil Engineering and Geosciences

Hydraulic Engineering, Civil Engineering and Geosciences

The environment in the Yellow River Delta (YRD) is under stress from large socio-economic pressures, leading to air, soil and water pollution. A Sino-Dutch project the Sustainable Development YRD project (1995 – 1997) was undertaken with the principle goal of contributing to the sustainable, long-term development of the Yellow River Delta. Objectives and criteria for sustainable development were defined. One of the main project challenges was to show how to use the limited fresh water resources in a sustainable way. This was undertaken using integrated and analytical tools in which future developments and strategies were systematically analysed. Such an approach provides a strong incentive to begin communication and develop mutual understanding between the different responsible authorities and stakeholders., Hydraulic Engineering, Civil Engineering and Geosciences

Coupled chemistry-climate model simulations covering the recent past and continuing throughout the 21st century have been completed with a range of different models. Common forcings are used for the halogen amounts and greenhouse gas concentrations, as expected under the Montreal Protocol (with amendments) and Intergovernmental Panel on Climate Change A1b Scenario. The simulations of the Antarctic ozone hole are compared using commonly used diagnostics: the minimum ozone, the maximum area of ozone below 220 DU, and the ozone mass deficit below 220 DU. Despite the fact that the processes responsible for ozone depletion are reasonably well understood, a wide range of results is obtained. Comparisons with observations indicate that one of the reasons for the model underprediction in ozone hole area is the tendency for models to underpredict, by up to 35%, the area of low temperatures responsible for polar stratospheric cloud formation. Models also typically have species gradients that are too weak at the edge of the polar vortex, suggesting that there is too much mixing of air across the vortex edge. Other models show a high bias in total column ozone which restricts the size of the ozone hole (defined by a 220 DU threshold). The results of those models which agree best with observations are examined in more detail. For several models the ozone hole does not disappear this century but a small ozone hole of up to three million square kilometers continues to occur in most springs even after 2070., authorCount :38

The goal of the Chemistry-Climate Model Validation (CCMVal) activity is to improve understanding of chemistry-climate models (CCMs) through process-oriented evaluation and to provide reliable projections of stratospheric ozone and its impact on climate. An appreciation of the details of model formulations is essential for understanding how models respond to the changing external forcings of greenhouse gases and ozone-depleting substances, and hence for understanding the ozone and climate forecasts produced by the models participating in this activity. Here we introduce and review the models used for the second round (CCMVal-2) of this intercomparison, regarding the implementation of chemical, transport, radiative, and dynamical processes in these models. In particular, we review the advantages and problems associated with approaches used to model processes of relevance to stratospheric dynamics and chemistry. Furthermore, we state the definitions of the reference simulations performed, and describe the forcing data used in these simulations. We identify some developments in chemistry-climate modeling that make models more physically based or more comprehensive, including the introduction of an interactive ocean, online photolysis, troposphere-stratosphere chemistry, and non-orographic gravity-wave deposition as linked to tropospheric convection. The relatively new developments indicate that stratospheric CCM modeling is becoming more consistent with our physically based understanding of the atmosphere.

In this collaborative project of the Delta Alliance a framework for delta assessment is proposed, building on the work done for the Aquaterra 2009 conference in Amsterdam and elaborating recent recommendations of the World Estuary Alliance conference (hosted by WWF in Shanghai, June 2010) regarding the development of a worldwide assessment of estuaries by means of ‘scorecards’. This framework links the DPSIR approach with a Layer model for a delta, which should be seen as a first step towards a more elaborated framework, to be developed in due time with relevant stakeholders. The integrated approach takes into account the different ‘layers’ of the delta system and related governance issues. Three physical planning layers are recognized: the Occupation layer (land and water use), the Network layer (infrastructure), and the Base layer (natural resources), each with different but interrelated temporal dynamics and public-private involvement. The framework is used for describing deltas in a uniform format in order to make a comparative overview and analysis easier. Building on the contacts of the Delta Alliance (and World Estuary Alliance) each delta description is prepared by a Delta Wing Coordinator of the Delta Alliance (or another main contact person), in most cases in cooperation with several (sectoral) experts.