Big Water Research Articles

Study on flow pattern and separation performance of air–water swirl-vane separator

Two-phase mixture has a complicated separating process inside a swirl-vane separator which plays an important role in assuring a low wetness of the steam to turbine. To understand the flow pattern inside the swirl-vane separator and analyze the separation performance, a simplified swirl-vane steam separator made of transparent acrylic resin is studied by experiment in which the mixture of air and water is used as the working fluids. Experimental results reveal that the separation efficiency of the separator strongly depends on the flow pattern and the water velocity. The separation efficiency in the annular flow is higher than that of the mist flow and the churn flow. The pressure drop is mainly affected by the air flow rate and the water droplet diameter. Furthermore, a numerical model assuming water as sphere droplets and neglecting its deformation is developed to simulate the separator with Euler two-phase model and RSM turbulence model. It is founded that although the separation efficiency is not sensitive to the size of the big water droplets, it is affected significantly by the micro scale water droplets. By assuming that 94% water droplet equals the Sauter mean diameter and the other 6% is 0.4 times of the Sauter mean diameter, the separation efficiency predicted agrees well with the experimental results for the studied case.

Soil-Water Characteristic Curve for Unsaturated Mixed-Soil Considering Physical Form and Dry Density Effect

A test is conducted to get the soil-water characteristic curve for three typical composite unsaturated soils in west Sichuan, considering its physical composition, physical form and dry density. Test data shows that the variation of physical composition, particle size and dry density can result in great change of soil-water characteristic curve. The bigger the dry density is and the more hydrophilic mineral it has, the more gently the soil-water characteristic curve is, and the higher dry density soil sample has higher residual moisture content. In addition, matrix suction decreased with less clay content and more content under the same water content. For three typical composite unsaturated soils, the change of soil-water characteristic curve resulting from variation of dry density is less in bigger water content, and is more in lower water content.

Study on Transforming from Vegetable-Residue to Roughage

The use rate of the vegetable-residue is low which pollution-free processing does not reach the designated position. In order to resolve the problem of vegetable residues treatment, the research focus on transforming from vegetable-residue to feed for livestock and poultry combining with its characteristics of big water content and strong seasonality. Firstly, the vegetable cakes with about 45% moisture content were made of vegetable-residue by cleaning, beating, pressure filtration, batching, mixing, granulating, cooling and packaging. The orthogonal experiment method was used to optimize the addition amount of bentonite, wheat middling, powdered rice hulls, binder and corn protein powder into vegetables particle roughage of poultry and vegetables honeycomb roughage of livestock from vegetable cakes which selected the forming ratio as the indicator. The results showed that when the addition amount of bentonite was 20%, wheat middling was 20%, powdered rice hulls was 20%, corn protein powder was 5%, the vegetables particle roughage had the best forming ratio, while the addition amount of bentonite 12.5%, wheat middling 10%, powdered rice hulls 15%, corn protein powder 3%, binder 2%, the livestock vegetables honeycomb roughage had the best forming ratio. The results would provide the references for vegetable-residue industrial treatment.

Simulation and analysis of ice processes in an artificial open channel

The Middle Route Project for South-to-North Water Transfer, which consists of a long artificial open channel and various hydraulic constructions, is a big water conveyance system. A numerical modeling of water conveyance in the ice period for such large-scale and long distance water transfer project is developed based on the integration of a river ice model and an unsteady flow model with complex inner boundaries. A simplified method to obtain the same flow discharge in the upstream and downstream of the structure by neglecting the storage effect is proposed for dealing with the inner boundaries. According to the measured and design data in winter-spring period, the whole ice process, which includes the formation of the ice cover, its development, the melting and the breaking up as well as the ice-water dynamic response during the gate operation for the middle route, is simulated. The ice characteristics and the water conveyance capacity are both analyzed and thus the hydraulic control conditions for a safety regulation are obtained. At last, the uncertainties of some parameters related to the ice model are discussed.

The significance of cytogenetics for the study of karyotype evolution and taxonomy of water bugs (Heteroptera, Belostomatidae) native to Argentina

Male meiosis behaviour and heterochromatin characterization of three big water bug species were studied. Belostoma dentatum (Mayr, 1863), Belostoma elongatum Montandon, 1908 and Belostoma gestroi Montandon, 1903 possess 2n = 26 + X1X2Y (male). In these species, male meiosis is similar to that previously observed in Belostoma Latreille, 1807. In general, autosomal bivalents show a single chiasma terminally located and divide reductionally at anaphase I. On the other hand, sex chromosomes are achiasmatic, behave as univalents and segregate their chromatids equationally at anaphase I. The analysis of heterochromatin distribution and composition revealed a C-positive block at the terminal region of all autosomes in Belostoma dentatum, a C-positive block at the terminal region and C-positive interstitial dots on all autosomes in Belostoma elongatum, and a little C-positive band at the terminal region of autosomes in Belostoma gestroi. A C-positive band on one bivalent was DAPI negative/CMA3 positive in the three species. The CMA3-bright band, enriched in GC base pairs, was coincident with a NOR detected by FISH. The results obtained support the hypothesis that all species of Belostoma with multiple sex chromosome systems preserve NORs in autosomal bivalents. The karyotype analyses allow the cytogenetic characterization and identification of these species belonging to a difficult taxonomic group. Besides, the cytogenetic characterization will be useful in discussions about evolutionary trends of the genome organization and karyotype evolution in this genus.

Research solutions technical - water technology to reduce the water loss for water supply system of Hochiminh city

The HCMC water supply system have built from the French Colonial period, and developed without planning and systematic study during the war time. In the beginning, this system used for the small town Saigon- Gia Dinh. Today, the capacity of water supply system is 1,85 million m3/day and will increase up to 2,5 million in next few year and up to 4-5 million m3/day according with the HCMC water supply system planning approved by Government. The climate change issues, salt water lever increase, polution... affect directly into the raw water resource of the existing and future water treatment plant. Beside that, the big size water supply transmission pipe line and the distribution water supply system of 06 hydrolique zone in HCMC damaged according with time : bad quality and No- update information of pipe system… It bring the real water loss level in HCMC so high up to 40% - 50% .The acceptable technologies & techniques solution to find the leak, optimal management for the water supply system to reduce the water loss is extremely essential, to support the clean water resources for the sustainable development of the HCM City.

The dynamic ice loads on conical structures

Two series of model tests were performed to observe the dynamic ice loads on conical structures. The variable testing parameters include the water line diameter of the model cone and ice parameters. During small water line diameter tests, two-time breaking is found to be the typical failure of ice before steep conical structure. This failure process is observed to be controlled by other factors, as ice speed and the D/h ratio. During big water line diameter tests, the ice sheet failed non-simultaneously around the conical surface. As an analyzing result, a new dimensionless parameter defined as the impact factor Im was established. It was found that the l/h ratio decreases with the increase of Im in a quadratic relationship. The global ice force was found increasing with lower D/h ratio, but reducing with higher D/h ratio and the subsequent number of independent zones.

Fireproofing Performance Research of Water Curtain

The experimentation and numerical simulating have been done to validate the fireproofing performance of big water curtain. The breadth and highness of water curtain is 15m and 12.5m. The dimension of fire space: 18m×15m×12.5m (length×breadth×highness). The dimension of no fire space: 42m×15m×12.5m (length×breadth×highness). The result shows that: water curtain can prevent fire propagating and drops in temperature clearly; the water curtain fireproofing is feasible and effective; flux and thickness of the water curtain and the diameter of drip have major influence upon effect of the water curtain fireproofing. The conclusion of this paper should be helpful for the fireproofing water curtain design.

Is there any benefit in artificial collapse of human blastocysts prior to vitrification?

Today, vitrification of human blastocysts provides an excellent outcome although a big water filled cavity called the blastocoele needs to be dehydrated prior to the cooling steps of vitrification. The replacement of water by the cryoprotectant seems to be the supported by artificially collapsing of the blastocoel. Therefore we started to apply artificial collapsing on human blastocysts using a laser pulse prior to vitrification, and then compared outcome data with frozen embryo transfers (FET), where no artificial collapse was applied.

The drivers of risk to water security in Shanghai

Big cities are often said to have big water problems, and Shanghai is no exception. In this paper, we examine and compare the influence of the major factors that give rise to the risk of water insecurity in Shanghai. There is an extensive and diverseliterature onthese issues, dealtwith in isolation, and here, we provide a synthesis of the litera- ture, together with our own assessments and calculations, to assess what are the risks to Shanghai's water supply and what is our degree of confidence in this assessment. We describe the systems that supply water to the city, and past and future changes in the systems, including changes in the glaciers that supply some water to the river, changes in cli- mate, changes in land use, the construction of dams, and water diversions. We show how, at the same time as Shanghai is increasing its dependence on the Yangtze river, waterdiversionsandsealevelriseareincreasingtheriskthat this water will be too saline to consume at certain times of the year. This analysis suggests that most of the major drivers of the risk to water security in Shanghai are within the power of environmental managers to control.

Integral Space Concrete Roof Structure System Optimization Research

Based on the experimental study, summarizes the disadvantages of the test roof; On the same premise of the roof to keep the overall appearance, the structural system of the roof is optimized ; The content of the optimized structural system includes the layout of the structural system, the establishment of the calculation model, the optimization of internal support system, the calculation of kinds of members, etc.; The integrity of the roof are enhanced after optimization, and more accord with the concrete shell space structure characteristics, and provided a convenient for the big water construction. Compared to the traditional roof, the optimized roof save about 30% of the costs.

Long-term climate impact on the Lake Victoria region influences water level fluctuation and resource availability

Historical climate parameters of the Tanzania part of the Lake Victoria region were studied focusing on rainfall variations and the lake water level. This study was prompted by the recent lake water recession after the big water level change which was observed in 1960s. Recorded rainfall pattern of the region was analysed for establishing their linkages to the changing lake environment. Similarly, community understanding of the observed changes in relation to climatic changes in the region was explored for comparison with recorded meteorological information for the past three decades from 1976–2005. It is presented that the region experiences an East–West rainfall pattern variation. The variations of rainfall relative to monthly average values indicated highest positive anomalies (529 mm) in March but this was during the second decade (1986 -1995) with lowest value (149 mm) during wet season. However the last decade (1996 -2005) had the highest anomaly value (~361 mm). Generally decade 1 and 3 showed higher rainfall availability than decade 2. These results implied linkage between rainfall variations with Lake water level. In addition, the observation was supported by the model prediction which indicated past (1961 – 2000) and future (2045 – 2065) trends of the regional rainfall pattern to be in a varying trends. The variation of rainfall is shown to affect all livelihood systems for communities in the region. Like in the past, the Lake Victoria region should expect similar changes of the water level which now increasingly brings about serious impact to their livelihood.

Sediment and nutrient deposition in Lake Volta in Ghana due to Harmattan dust

Abstract Harmattan is a dust-laden north-easterly wind that blows from the Sahara towards the Gulf of Guinea in the period November to March. It is the dominant wind in the north of Ghana while at the coast in the south it only occurs sporadically and here westerly or south-westerly winds dominate. Some of the dust is trapped in the vegetation, in lakes and other inland waters, and a little on the bare land. In this study, we determine the amount of sediment and nutrients that are deposited by this wind in big water bodies, exemplified by the dust deposition in the Harmattan period in the man-made Lake Volta. These depositions are compared with similar inputs by the rivers. On average, approximately 146,000 t of mineral matter and 42,000 t of organic matter are deposited per year in the Lake during the Harmattan periods. This is the equivalent of approximately 1% of the suspended sediment input by the rivers. The total amounts of Ca, P and Mg deposited during the Harmattan period are3000 t, 350 t and 810 t, respectively. About 40% of the Ca deposited is readily or plant available, for P and Mg it is about 50% and 20%, respectively. If the amount of readily available nutrients coming from the Harmattan dust is held against the influx of readily available (dissolved) Ca, Mg and P from the rivers to Lake Volta, it appears that the Harmattan dust accounts for only 0.7‰ Mg, 4.8‰ Ca, and 2.1% P. It must therefore be concluded that the contribution of nutrients to Lake Volta by the Harmattan dust is very limited.

CAN WE SAVE THE CALIFORNIA DELTA IN THE FACE OF SEA LEVEL RISE?

ABSTRACTSea level rise would profoundly affect low‐lying coastal and estuary regions of the world and especially the Sacramento–San Joaquin delta in California. This delta, the largest on the west coast of the US, has about 120 000 ha below sea level, protected by levees, many on weak peat soil. The delta is also the hub of water transfer from north to south for two big water projects, which are vulnerable to ocean saltwater intrusion.Sea level has been rising slowly and is projected to rise more in the next 100 years. This, coupled with continued subsidence, will make it more difficult to protect low‐lying delta lands from inundation. The biggest threat is during high water storm events, but also a few summer dry season breaks have affected water exports.Since current rates of ocean rise are slow, a modest continuing effort in levee strengthening to handle a rise of 0.3 to 0.5 cm yr‾¹ could maintain present levels of flood protection for decades. Eventually hard choices will have to be made on which islands to save as costs rise and with better estimates of ocean rise. More than farmland is involved; much infrastructure, such as roads and pipelines, is as well. Copyright © 2011 John Wiley & Sons, Ltd.

The effect of varying fat content on the microstructure of Oaxaca cheese, a typical pasta filata cheese

The effect of varying fat content in Oaxaca cheese, a typical pasta filata, on microstructure was described. Microstructure of cheeses was analysed by scanning electron microscopy (SEM) and light microscopy (LM) in nondehydrated and dehydrated samples. In nondehydrated samples, protein fibres were wide and compact in fat‐free cheese, and big serum channels were approximately 100 μm in width. Width of protein fibres and size of channels decreased as fat content increased. Small channels seemed to be occupied only by fat, while in big channels, water and fat were observed. LM both confirmed and supplemented the observations made by SEM, particularly the presence and distribution of fat in channels.

A New Coarse-Grained Force Field for Membrane-Peptide Simulations.

We present a new coarse-grained (CG) model for simulations of lipids and peptides. The model follows the same topology and parametrization strategy as the MARTINI force field but is based on our recently developed big multipole water (BMW) model for water (J. Phys. Chem. B2010, 114, 10524-10529). The new BMW-MARTINI force field reproduces many fundamental membrane properties and also yields improved energetics (when compared to the original MARTINI force-field) for the interactions between charged amino acids with lipid membranes, especially at the membrane-water interface. A stable attachment of cationic peptides (e.g., Arg8) to the membrane surface is predicted, consistent with experiment and in contrast to the MARTINI model. The model predicts electroporation when there is a charge imbalance across the lipid bilayer, an improvement over the original MARTINI. Moreover, the pore formed during electroporation is toroidal in nature, similar to the prediction of atomistic simulations but distinct from results of polarizable MARTINI for small charge imbalances. The simulations emphasize the importance of a reasonable description of the electrostatic properties of water in CG simulations. The BMW-MARTINI model is particularly suitable for describing interactions between highly charged peptides with lipid membranes, which is crucial to the study of antimicrobial peptides, cell penetrating peptides, and other proteins/peptides involved in the remodeling of biomembranes.

Driving Force for the Association of Hydrophobic Peptides: The Importance of Electrostatic Interactions in Coarse-Grained Water Models

The hydrophobic effect plays a central role in many biological processes, including protein folding and aggregation. The hydrophobic interaction between solutes, such as helical peptides, is believed to be of entropic origin and driven by the increase in the entropy of water due to association. In this work, we examine the association between peptides in water using several coarse-grained (CG) models, such as MARTINI (MAR), polarizable MARTINI (POL), and big multipole water (BMW) models, where four atomistic water molecules are grouped into a single CG unit. All models predict that a pair of helical peptides (Ala20 and Leu20) has favorable association free energy. The BMW model is the only model, however, in which this association is entropy-driven, as has been previously established with atomistic simulations and experiments. The MAR and POL models, where the CG water particles do not have a quadrupole moment, predict an enthalpy-driven association, with a negligible entropy change upon association. Similarly, the association of two rigid cylinders in water is found to be enthalpy-driven when the water is described with the CG model of Shinoda et al. that includes a soft-core nonelectrostatic interaction, while BMW predicts an entropy-driven association. These results emphasize the importance of electrostatic interactions in water for the qualitative features of the thermodynamics of biophysical systems.

Dynamic ice loads on conical structures

Two series of model tests were performed to observe the dynamic ice loads on conical structures. The variable testing parameters include the water line diameter of the model cone and ice parameters. During small water line diameter tests, two-time breaking is found to be the typical failure of ice on steep conical structure, and also be controlled by other factors, such as ice speed and the cone angle. During big water line diameter tests, the ice sheet failed nonsimultaneously around the cone. Several independent zones of bending were found in the nonsimultaneous failure process of ice. With the increase of the ratio of D/h and the number of independent zones, the total ice force was found being gradually reduced.

SPATIAL FORMATION OF RESIDENTIAL SETTLEMENTS ON SQUATTER AREA

The aim of this study is to clarify spatial formation of residential settlements on squatter area by analyzing spatial formation and utilization of houses and open spaces on Borei Keila which is one of the largest squatter areas in Phnom Penh, Cambodia. We conclude the results as below from the data mostly based on the field survey. 1. Simple beds, fire equipment and big water pot are the basic components of interior space. Houses over thirty square meters generally have separate living, dining, private and sanitary rooms. 2. Small open spaces and narrow alleys compose the residential block. Though this residential area was made by each self-built house, definite levels exists on width of the alleys. 3. Around eighty percent of houses have devices such as deep eaves and outside bed to connect interior and exterior space. 4. Outside behaviors are cooking, eating, bathing, washing clothes, discharging, conversation, play, taking rest, sleep, selling and buying, working and others.

Bottled and sold: the story behind our obsession with bottled water

Peter Gleick knows water. A world-renowned freshwater expert, Gleick is a MacArthur Foundation genius, and according to the BBC, an environmental visionary. And he drinks from the tap. Why don't the rest of us? Bottled and Sold shows how water went from being a free natural resource to one of the most successful commercial products of the last one hundred years - and why we are poorer for it. It's a big story and water is big business. Every second of every day in the United States, a thousand people buy a plastic bottle of commercially produced water, and every second of every day a thousand more throw one of those bottles away. That adds up to more than thirty billion bottles a year and tens of billions of dollars. Have we simply been hoodwinked by corporate executives or are there legitimate reasons to buy all those bottles? With a scientist's eye and a natural storyteller's wit, Gleick investigates whether claims about the relative safety, convenience, and taste of bottled vs. tap hold water. And he exposes the true reasons we've turned to the bottle, from fear-mongering by business interests and our own vanity to the breakdown of public systems and global inequities. Jewel-encrusted designer H2O may be laughable, but the debate over commodifying water is deadly serious. It comes down to society's choices about the human right to water, the role of government and free markets, the importance of being green, and fundamental values. Gleick gets to the heart of the bottled water craze, exploring what it means for our most basic necessity to become a luxury.