The energy–water nexus: are there tradeoffs between residential energy and water consumption in arid cities?

Water scarcity, energy consumption, and air temperature regulation are three critical resource and environmental challenges linked to urban population growth. While appliance efficiency continues to increase, today’s homes are larger and residents are using more energy-consuming devices. Recent research has often described the energy–water nexus as a “tradeoff” between energy and water due to reduced temperatures resulting from irrigated vegetation. Accordingly, some arid cities have implemented landscape-conversion programs that encourage homeowners to convert their yards from grass (mesic) to drought-tolerant (xeric) landscapes to help conserve water resources. We investigated these relationships in Phoenix, Arizona by examining energy and water data for the summer months of June–September 2005 while temperature variability was analyzed from a local heat wave. Results show parallel consumption patterns with energy and water use strongly correlated and newer homes using more of both. The counterintuitive findings show that “drought-resistant” models may not be beneficial for community health, environment, or economics and that this issue is further complicated by socio-economic variables.     

The energy–water limitation threshold explains divergent drought responses in tree growth,needle length,and stable isotope ratios

Predicted increases in extreme droughts will likely cause major shifts in carbon sequestration and forest composition. Although growth declines during drought are widely documented, an increasing number of studies have reported both positive and negative responses to the same drought. These divergent growth patterns may reflect thresholds (i.e., nonlinear responses) promoted by changes in the dominant climatic constraints on tree growth. Here we tested whether stemwood growth exhibited linear or nonlinear responses to temperature and precipitation and whether stemwood growth thresholds co-occurred with multiple thresholds in source and sink processes that limit tree growth. We extracted 772 tree cores, 1398 needle length records, and 1075 stable isotope samples from 27 sites across whitebark pine's (Pinus albicaulis Engelm.) climatic niche in the Sierra Nevada. Our results indicated that a temperature threshold in stemwood growth occurred at 8.4°C (7.12–9.51°C; estimated using fall-spring maximum temperature). This threshold was significantly correlated with thresholds in foliar growth, as well as carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope ratios, that emerged during drought. These co-occurring thresholds reflected the transition between energy- and water-limited tree growth (i.e., the E–W limitation threshold). This transition likely mediated carbon and nutrient cycling, as well as important differences in growth-defense trade-offs and drought adaptations. Furthermore, whitebark pine growing in energy-limited regions may continue to experience elevated growth in response to climate change. The positive effect of warming, however, may be offset by growth declines in water-limited regions, threatening the long-term sustainability of the recently listed whitebark pine species in the Sierra Nevada.     

China’s water footprint by province,and inter-provincial transfer of virtual water

Water shortages and the uneven distribution of water resources restrict China’s sustainable development. The concepts of virtual water and water footprints provide a new approach to alleviate regional shortages of Chinese water resources by the inter-provincial allocation of commercial water resources. In this study, an interregional input-output model was applied to quantitatively estimate the water footprint of each province in China and to quantify the inter-provincial transfer of virtual water. The results indicated that there was considerable diversity in the water footprints of the various provinces. Provinces with larger populations and greater GDP had larger water footprints, and developed regions had higher proportions of external water footprints. From the perspective of final demand, local consumption was the main factor driving the water footprints of these provinces. From the perspective of sectoral structure, the agricultural water footprint had a larger proportion in these provinces. The transfer of virtual water in China did not occur from regions with abundant water resources to those suffering from water shortages, but it generally occurred from west to east, from inland to coastal areas, and from underdeveloped to developed regions. Many water-deficient regions also had large net virtual water exports. Water shortages in China will be alleviated by the enhancement of industrial water-use efficiency in water-deficient regions, the transfer of water-intensive industries to regions with abundant water resources, and the development of tertiary industries with low water consumption.     

Driving force of water entry into hydrophobic channels of carbon nanotubes: entropy or energy?

Spontaneous entry of water molecules inside single-wall carbon nanotubes (SWCNTs) has been confirmed by both simulations and experiments. Using molecular dynamics simulations, we have studied the thermodynamics of filling of a (6,6) carbon nanotube in a temperature range from 273 to 353 K and with different strengths of the nanotube–water interaction. From explicit energy and entropy calculations using the two-phase thermodynamics method, we have presented a thermodynamic understanding of the filling behaviour of a nanotube. We show that both the energy and the entropy of transfer decrease with increasing temperature. On the other hand, scaling down the attractive part of the carbon–oxygen interaction results in increased energy of transfer while the entropy of transfer increases slowly with decreasing the interaction strength. Our results indicate that both energy and entropy favour water entry into (6,6) SWCNTs. Our results are compared with those of several recent studies of water entry into carbon nanotubes.     

So,why is water biologically important?

Some brief impressionistic and necessarily subjectively based comments on the content of the Discussion Meeting are made. It is pointed out that the principal thrust of most of the presentations was directed towards structural aspects of proteins in various media. Comments are also made on the necessary interplay between the medium in which biomolecules occur and the interatomic forces between the atoms comprising the biomolecules. Some speculation is made on the possibility of life-forms existing in extreme environments.     

From evergreen to deciduous tropical forests: how energy–water balance,temperature, and space influence the tree species composition in a high diversity region

Background: Understanding floristic and geographic patterns in one of the most biodiverse regions in the world – the Atlantic forest of eastern Bahia, Brazil – can identify the drivers of diversity in tropical forests and provide useful information for biological conservation.

Aims: To understand the role of both climate and geographical location on variation in tree species composition in a region characterised by an abrupt transition from wet forests to semi-arid thorn-woodlands. To test whether a regional classification of forests according to elevation belts and leaf flush pattern is consistent with floristic composition.

Methods: We submitted 14,094 tree species occurrence records and 31 geo-climatic variables prepared for 57 sites in eastern Bahia, Brazil, to multivariate and regression analyses and variance partitioning.

Results: Climate and space were both significantly (P ≤ 0.05) contributing to explaining floristic variations. Actual evapotranspiration, duration of water deficit, and minimum temperature of coldest month were the main predictors. Floristic differences were significant except when comparing evergreen lower plains and upper plains forests.

Conclusions: Although distance among sites may play an important role, species composition is chiefly influenced by environmental gradients. This highlights environmental heterogeneity as a key factor in the planning of biodiversity conservation in tropical forests.     

Natural photosystems from an engineer’s perspective: length,time, and energy scales of charge and energy transfer

The vast structural and functional information database of photosynthetic enzymes includes, in addition to detailed kinetic records from decades of research on physical processes and chemical reaction-pathways, a variety of high and medium resolution crystal structures of key photosynthetic enzymes. Here, it is examined from an engineer’s point of view with the long-term goal of reproducing the key features of natural photosystems in novel biological and non-biological solar-energy conversion systems. This survey reveals that the basic physics of the transfer processes, namely, the time constraints imposed by the rates of incoming photon flux and the various decay processes allow for a large degree of tolerance in the engineering parameters. Furthermore, the requirements to guarantee energy and electron transfer rates that yield high efficiency in natural photosystems are largely met by control of distance between chromophores and redox cofactors. This underlines a critical challenge for projected de novo designed constructions, that is, the control of spatial organization of cofactor molecules within dense array of different cofactors, some well within 1 nm from each other.     

Effect of uniconazole and limited water on growth,water relations,and mineral nutrition of “Lalandei” Pyracantha

Pyracantha (Pyracantha coccinea M. J. Roem. Lalandei) plants were treated with uniconazole at 0.5 mg ai container^–1 as a medium drench, 150 mg ai L^–1 as a foliar spray, or left untreated. Plants from all treatments were placed under three water regimes: drought acclimated, nonacclimated and later exposed to drought, or nonstressed. Acclimated plants were conditioned by seven 4-day stress cycles (water withheld), while nonacclimated were well watered prior to a single 4-day stress cycle at the same time as the seventh drought cycle of acclimated plants. Nonstressed plants were well watered throughout the study. Nonstressed plants had higher leaf water potentials and leaf conductances than acclimated and nonacclimated plants, and transpiration rates were higher in nonacclimated than acclimated plants. Uniconazole did not affect leaf water potential, leaf conductance, or transpiration rate. Acclimated plants had smaller leaf areas and leaf, stem, and root dry weights than nonacclimated or nonstressed plants. Plants drenched with uniconazole had the lowest stem and root dry weights. Acclimated plants also contained higher N concentrations than nonacclimated or nonstressed plants, and higher P concentrations than nonacclimated plants. Uniconazole medium drench treatments increased levels of Mn and P. Calcium concentration was increased in plants receiving either medium drench or foliar applications.     

Foraging in male bumblebees (Bombus lucorum L.): maximizing energy or minimizing water load?

Summary The O₂, CO₂, and H₂O exchange of single flying male bumblebees (Bombus lucorum and B. terrestris) were measured simultaneously. A respiratory quotient RQ=1 was found for all activities investigated (torpor-flight). The dependence of respiratory CO₂ production in flight on body-weight was measured: for a 220-mg male bumblebee it amounts to 24.5 mg CO₂/h (=56.4 ml O₂/g·h). The corresponding evaporative water loss amounts to 6 mg H₂O/h. Males tranferred to a climatic test chamber and conditioned to artificial flower feeders started to fly, after a few days of acclimatization, in typical scent-marked flight-paths. The daily pattern of flight activity was recorded: the mean total time in flight amounts to 244 min, and the corresponding daily flight length is about 17 km. At 20°C and 50% relative humidity (RH) a daily uptake of 180 l ( 220mg) of 50% sugar solution was measured, equal to the mean body weight of the male bumblebees. Since the body weight remains constant on consecutive days a 24-h energy- and water-budget could be calculated. The energy-budget is balanced; the activities observed can be fuelled with the sugar available. About 70% of the energy is used for the 4 h of flight activity. With the daily nectar volume 110 mg of water is ingested; in the oxidation of 110 mg sugar, 66 mg of metabolic water is produced and 40 mg water is dissipated by the evaporative water-loss. Thus, to have a balanced water-budget, 136 mg of water must be voided in 24 h, which equals the total body-water of the bumblebees. Nectar is a nutrient of high water content which not only provides the sugar necessary for activity but also, in most circumstances, an excess of water. The effect of this high water load in limiting daily activity is discussed and compared with the water- and osmoregulation of hummingbirds. The strategy of maximizing energy for a male bumblebee must be one of minimizing water load.     

Lorenz was right, or does aggressive energy accumulate?

Evidence supporting the fact that inherited mechanisms of regulation of aggressive behavior as a result of a repeated experience of aggression ending in victories are transformed into pathological mechanisms based on accumulation of neurochemical shifts in the brain, enhancing aggressiveness, and forming aggressive motivation in aggressive winners. This confirms the concept by Lorenz on the existence of a mechanism (but not instinct) of a spontaneous accumulation of aggressive energy that needs a discharge and formation of permanent attraction to manifestation of aggression.     

Effects of energy content and energy density of pre-portioned entrées on energy intake

Pre-portioned entrées are commonly consumed to help control portion size and limit energy intake. The influence of entrée characteristics on energy intake, however, has not been well studied. We determined how the effects of energy content and energy density (ED, kcal/g) of pre-portioned entrées combine to influence daily energy intake. In a crossover design, 68 non-dieting adults (28 men and 40 women) were provided with breakfast, lunch, and dinner on 1 day a week for 4 weeks. Each meal included a compulsory, manipulated pre-portioned entrée followed by a variety of unmanipulated discretionary foods that were consumed ad libitum. Across conditions, the entrées were varied in both energy content and ED between a standard level (100%) and a reduced level (64%). Results showed that in men, decreases in the energy content and ED of pre-portioned entrées acted independently and added together to reduce daily energy intake (both P < 0.01). Simultaneously decreasing the energy content and ED reduced total energy intake in men by 16% (445 ± 47 kcal/day; P < 0.0001). In women, the entrée factors also had independent effects on energy intake at breakfast and lunch, but at dinner and for the entire day the effects depended on the interaction of the two factors (P < 0.01). Simultaneously decreasing the energy content and ED reduced daily energy intake in women by 14% (289 ± 35 kcal/day; P < 0.0001). Both the energy content and ED of pre-portioned entrées affect daily energy intake and could influence the effectiveness of such foods for weight management.     

Fluorescence lifetime,yield, energy transfer and spectrum in photosynthesis, 1950–1960*

The fluorescence lifetime of chlorophyll agives information about the primary photo-physical events in photosynthesis. Most of the light energy absorbed by chlorophylls is utilized for photochemistry. There are two main additional pathways competing for the absorbed light energy: fluorescence and radiationless internal conversion (heat). Only a few percent of the absorbed energy proceeds along these two pathways. This historical minireview focuses on the first direct measurements of the lifetime of chlorophyll fluorescence, the time it takes to transfer energy from phycoerythrin to chlorophyll a, and the discovery of the fluorescence band at 720 nm (F720; then attributed to a dimer of chlorophyll). These works were carried out during the the late 1950s to the early 1960s in the laboratory of Professor Eugene Rabinowitch at the University of Illinois, Urbana-Champaign [Brody (1995) Photosynth Res 43: 67–74]. This Minireview is dedicated to Professor Eugene Rabinowitch (1901–1973), mentor of the author (Steve Brody) as well as of the editor, and authors classmate (Govindjee). The career and contributions of Eugene Rabinowitch are available in a dedication by Bannister (1972). This revised version was published online in June 2006 with corrections to the Cover Date.     

How do salinity and water stress affect transport of water,assimilates and ions to tomato fruits?

The study was conducted in order to determine whether water stress affects the accumulation of dry matter in tomato fruits similarly to salinity, and whether the increase in fruit dry matter content is solely a result of the decrease in water content. Although the rate of water transport to tomato fruits decreased throughout the entire season in saline water irrigated plants, accumulation rates of dry matter increased significantly. Phloem water transport contributed 80–85% of the total water transport in the control and water-stressed plants, and over 90% under salinity. The concentration of organic compounds in the phloem sap was increased by 40% by salinity. The rate of ions transported via the xylem was also significantly increased by salinity, but their contribution to fruit osmotic adjustment was less. The rate of fruit transpiration was also markedly reduced by salinity. Water stress also decreased the rate of water transport to the tomato fruit and increased the rate of dry matter accumulation, but much less than salinity. The similar changes, 10–15%, indicate that the rise in dry matter accumulation was a result of the decrease in water transport. Other parameters such as fruit transpiration rates, phloem and xylem sap concentration, relative transport via phloem and xylem, solutes contributing to osmotic adjustment of fruits and leaves, were only slightly affected by water stress. The smaller response of these parameters to water stress as compared to salinity could not be attributed to milder stress intensity, as leaf water potential was found to be more negative. Measuring fruit growth of girdled trusses, in which phloem flow was inactive, and comparing it with ungirdled trusses validated the mechanistic model. The relative transport of girdled as compared to ungirdled fruits resembled the calculated values of xylem transport.     

Biofouling in water systems – cases,causes and countermeasures

Biofouling is referred to as the unwanted deposition and growth of biofilms. This phenomenon can occur in an extremely wide range of situations, from the colonisation of medical devices to the production of ultra-pure, drinking and process water and the fouling of ship hulls, pipelines and reservoirs. Although biofouling occurs in such different areas, it has a common cause, which is the biofilm. Biofilms are the most successful form of life on Earth and tolerate high amounts of biocides. For a sustainable anti-fouling strategy, an integrated approach is suggested which includes the analysis of the fouling situation, a selection of suitable components from the anti-fouling menu and an effective and representative monitoring of biofilm development.     

How amyloplasts,water deficit and root tropisms interact?

Hydrotropism, the differential growth of plant roots directed by a moisture gradient, is a long recognized, but not well-understood plant behavior. Hydrotropism has been characterized in the model plant Arabidopsis. Previously, it was postulated that roots subjected to water stress are capable of undergo water-directed tropic growth independent of the gravity vector because of the loss of the starch granules in root cap columella cells and hence the loss of the early steps in gravitropic signaling. We have recently proposed that starch degradation in these cells during hydrostimulation sustain osmotic stress and root growth for carrying out hydrotropism instead of reducing gravity responsiveness. In addition, we also proposed that abscisic acid (ABA) and water deficit are critical regulators of root gravitropism and hydrotropism, and thus mediate the interacting mechanism between these two tropisms. Our conclusions are based upon experiments performed with the no hydrotropic response (nhr1) mutant of Arabidopsis, which lacks a hydrotropic response and shows a stronger gravitropic response than that of wild type (WT) in a medium with an osmotic gradient.Key words: starch, water deficit, auxin, abscisic acid, gravitropism, hydrotropismRoots of land plants sense and respond to different stimuli, some of which are fixed in direction and intensity (i.e., gravity) while other vary in time, space, direction and intensity (i.e., obstacles and moisture gradients). Directed growth of roots in relation to a gradient in moisture is called hydrotropism and begins in the root cap with the sensing of the moisture gradient. However, since gravity is an omnipresent accompaniment of Earthly life and many living process have evolved with it as a background constant, it is not surprising that root hydrotropism interacts with gravitropism.¹ The hydrotropic response in Arabidopsis, compare with other plants such as pea and cucumber^2,3 is readily observed even in the presence of gravity.^4,5 When Arabidopsis roots are subjected to a water gradient, such that the source of water is placed 180° opposed to the gravity vector, the roots will grow upwards, displaying positive hydrotropism. Therefore, it has been feasible to isolate so far two Arabidopsis mutants affected in their hydrotropic response.^5,6 Analysis of these mutants reveals new insights of the mechanism of hydrotropism. For one hand, the no hydrotropic response (nhr1) mutant lacks a hydrotropic response, and shows a stronger gravitropic response than that of wt and a modified wavy growth response in a medium with an osmotic gradient.^5,7 On the other hand, the mizu-kussei1 (miz1) mutant did not exhibit hydrotropism and showed regular gravitropism.⁶ Hence, the root hydrotropic response is both linked and unlinked from the gravitropic one. Nonetheless, miz1 roots also showed a reduced phototropism and a modified wavy growth response. This indicates that both MIZ1 and NHR1 are not exclusive components of the mechanism for hydrotropism and supports the notion that the root cap has assessment mechanisms that integrate many different environmental influences to produce a final integrated response.⁸ Thus, the physiological phenomena distinctively displayed by roots in order to forage resources from the environment are the result of integrated responses that resulted from many environmental influences sensed in the root cap.In the course of studying how gravity and water availability affected the perception and assessment of each other in root cap cells that generated the final root tropic response, we found that ABA is a critical regulator of the signal transduction mechanism that integrated these two-root tropisms.⁷ For this, we analyzed the long-term hydrotropic response of Arabidopsis roots in an osmotic gradient system. ABA, locally applied to seeds or root tips of nhr1, significantly increased root downward growth in a medium with an osmotic gradient (root length of nhr1 seedlings grown in this medium were on average 12.5 mm and plus 10 µM ABA were 25.1 mm). On the other hand, WT roots germinated and treated locally with ABA in this system were strongly gravitropic, albeit they had almost no starch in amyloplasts of root cap columella cells. Hydrotropically stimulated nhr1 roots, with or without ABA, maintained starch in amyloplastas, as opposed to those of WT. Therefore, the near-absence (WT) or abundant presence (nhr1) of starch granules does not affect the extent of downward gravitropism of roots in an osmotic gradient medium. Starch degradation in the wt might participate in osmoregulation by which root cells maintain turgor and consequently carry out hydrotropism, instead of reducing gravity responsiveness. In fact, it was just recently published that salt-induced rapid degradation of starch in amyloplasts is not likely the main reason for a negative gravitropic response seen under salt stress, because sos mutant roots of Arabidopsis showed negative gravitropic growth without any apparent rapid digestion of starch granules.⁹ Additionally, the stems of overwintering tubers of Potamogeton pectinatus are capable of elongating much faster in the absence than in the presence of oxygen for up to 14 days and its stems has an enhanced capacity for gravitropic movements in completely anoxic conditions.¹⁰ These authors hypothesized that ABA and starch degradation in the starchy tuber sustained stem cell elongation and cell division as well as differential growth required for the gravitropic response in these aquatic plants. These data taken together suggest that in conditions of anoxia, or water stress, ABA and degradation of starch play a critical role in the ability to survive relatively prolonged periods of unfavorable growth conditions. These players are critical when water or minerals are scarce since they regulate the enhancement of root downward growth. However, since roots can trail humidity gradients in soil, they can modulate their branching patterns (architecture) and thus respond to hydrotropism once a water-rich patch is found. Then the response of plants to gravity is principally one of nutrition (shoots to light, roots to mineral and water) and consequently must be regulated according to the long- and short-term environmental variables that occur during the development of the plant.Differential growth that occurs during the gravitropic and phototropic response has been explained according to the Cholodny-Went hypothesis, which states that the lateral transport of auxin across stimulated plant tissues is responsible for the curvature response.¹¹ Analysis of hydrotropism in some Arabidopsis agravitropic auxin transport mutants has demonstrated that these mutations do not influence their hydrotropic response.⁴ Furthermore, current pharmacological studies using inhibitors also indicated that both auxin influx and efflux are not required for hydrotropic response whereas auxin response is necessary for it.¹² These authors suggested a novel mechanism for auxin in root hydrotropism. Here, we analyzed whether asymmetric auxin distribution takes place across hydrotropically-stimulated roots using transgenic plants carrying a responsive auxin promoter (DR5) driving the expression of β-glucuronidase (GUS) or green fluorescent protein (GFP)^13,14 in wt and nhr1 backgrounds. Wt and nhr1 roots hydrotropically stimulated in a system with air moisture gradient⁵ showed no asymmetric expression of the DR5:: GUS or DR5::GFP (Fig. 1A and B). Nonetheless, nhr1 roots showed a substantial decrease in the signal driven by the DR5::GUS and GFP reporters in humidity saturated conditions (Fig. 1A, part b and B, part b), which might indicate that auxin-induced gene expression in the root cap was inhibited. It remains to be determined the significance of this inhibition in the no hydrotropic response phenotype displayed by nhr1 roots. Determination of the DR5::GUS expression in wt and nhr1 roots growing in an osmotic gradient medium for testing long-term hydrotropism revealed that the GUS signal was to some extent diminished in both wt or in nhr1 roots (Fig. 2C and D) compared to those roots growing in normal medium (Fig. 2A and B). An inhibitor of auxin response reduced hydrotropism,¹² and also inhibited auxin-dependent DR5::GUS expression.¹⁵ However, a decrease of DR5::GUS in wt root tips was not an impediment for developing an hydrotropic response. On the other hand, nhr1 roots also showed a decrease of DR5::GUS expression (Fig. 2B and D) and a complete absence of DR5::GFP (data not shown), which did not influence the extent of downward root gravitropism in water deficit conditions. Therefore, it is difficult to assign a role of auxin-induce gene expression in hydrotropism and further studies are required in order to unravel this issue. Furthermore, it needs to be resolved whether these expression studies oppose the idea that gradients in auxin precede differential growth in response to humidity gradients.Open in a separate windowFigure 1DR5:: GUS (A) and DR5::GFP (B) activity in the wild type NHR1 and nhr1 backgrounds. (A) Root tips hydrostimulated in a system with air moisture gradient (C and D) or grown in a saturated water conditions (A and B) stained with 1 mM 5-bromo-4-chloro-3-indolyl-β-d-glucuronic (X-Gluc) acid buffer under the same conditions for 80 min. (B) Root tips hydrostimulated as in (A) (C and D) or grown in a saturated water conditions (A and B) whose green fluorescent signal was visualized by confocal microscopy. Shown are images selected from at least 45 representative root tips. Bar = 29 µm.Open in a separate windowFigure 2Expression of DR5::GUS in wild type NHR1 and nhr1 backgrounds. Roots were hydrotropically stimulated for 8 days in a medium with an osmotic gradient (C and D) or grown in normal medium (A and B) and stained with X-Gluc acid buffer under the same conditions for 80 min. Shown are images selected from at least 50 representative root tips. Bar = 25 µm.Our studies⁷ revealed that ABA is a critical regulator of both root gravitropism and hydrotropism in water deficit conditions, and that the role of auxin under these conditions seems to differ from those observed in several studies thus far published on gravitropism made under well-water conditions. The molecular characterization of NHR1 and from other nhr-like mutants already isolated in our lab will clarify the mechanisms involved in this fascinating tropism.¹⁶     

Phase Behavior, Stability, and Mesomorphism of Monostearin–oil–water Gels

This paper is the characterization of a new material comprised of oil, water, monostearin and stearic acid, which can be used as a heart-friendly, low-saturate, trans fatty acid-free spreadable fat and shortening. Oil–water–monstearin mixtures formed a gel above 2% monostearin and 30% water and were stable over a month’s time. An increase in the storage modulus (G′), and peak melting temperature (T _m) was observed over time, which suggests a slow change in structure to a more solid form. Powder x-ray diffraction measurements at temperatures above the Krafft temperature of the monglyceride (57°C) indicated the existence of a lamellar liquid crystalline phase $ {\left( {L_{\alpha } } \right)} This paper is the characterization of a new material comprised of oil, water, monostearin and stearic acid, which can be used as a heart-friendly, low-saturate, trans fatty acid-free spreadable fat and shortening. Oil–water–monstearin mixtures formed a gel above 2% monostearin and 30% water and were stable over a month’s time. An increase in the storage modulus (G′), and peak melting temperature (T _m) was observed over time, which suggests a slow change in structure to a more solid form. Powder x-ray diffraction measurements at temperatures above the Krafft temperature of the monglyceride (57°C) indicated the existence of a lamellar liquid crystalline phase with a (001) reflection occurring at 50 ?. In addition to the 50 ? reflection at small angles, a wide angle reflection at 4.2 ? was observed upon cooling below 60°C, indicating a transition from the to the phase, which upon storage at 22°C for one day converted to the coagel, or β-gel phase.     

State of Lake Sysmäjärvi,Eastern Finland,after loading with mine water and municipal waste water for several decades

Hydrobiologia - The deep mining of copper and nickel at Outokumpu, Eastern Finland, lasted from 1910 to the late 1980s, during which period metalliferous waste water of high conductivity and...     

Biogeochemical processes at the sediment–water interface, Bombah Broadwater, Myall Lakes

Myall Lakes has experienced algal blooms in recent years which threaten water quality. Biomarkers, benthic fluxes measured with chambers, and pore water metabolites were used to identify the nature and reactivity of organic matter (OM) in the sediments of Bombah Broadwater (BB), and the processes controlling sediment-nutrient release into the overlying waters. The OM in the sediments was principally from algal sources although terrestrial OM was found near the Myall River. Terrestrial faecal matter was identified in muddy sediments and was probably sourced via runoff from farm lands. The reactive OM which released nutrients into the overlying waters was from diatoms, dinoflagellates and probably cyanobacteria. Microcystis filaments were observed in surface sediments. OM degradation rates varied between 5.3 and 47.1 mmol m^?2 day^?1 (64–565 mg m^?2 day^?1), were highest in the muddy sediments and sulphate reduction rates accounted for 20–40% of the OM degraded. Diatoms, being heavy sink rapidly, and are an important vector to transport catchment N and P to sites of denitrification and P-trapping in the sediments. Denitrification rates (mean ～4 mmol N m^?2 day^?1), up to 7 mmol N m^?2 day^?1 (105 mg N m^?2 day^?1) were measured, and denitrification efficiencies were highest (mean = 86 ± 4%) in the sandy sediments (～20% of the area of BB), but lower in the muddy sediments (mean = 63 ± 15%). These differences probably result from higher OM loads and anaerobic respiration in muddy sediments. Most DIP (>70%) from OM degradation was not released into overlying waters but remained trapped in surface sediments. Biophysical (advective) processes were responsible for the measured metabolite (O₂, CO₂, DSi, DIN and DIP) fluxes across the sediment–water interface.     

Excited-state proton-transfer reactions of 7-azaindole with water,ammonia and mixed water–ammonia: microsolvated dynamics simulation

Dynamics simulations of excited-state multiple proton transfer (ESMPT) reactions in 7-azaindole (7AI) with ammonia, mixed water–ammonia, and water molecules were investigated by quantum dynamics simulations in the first-excited state using RI-ADC(2)/SVP-SV(P) in the gas phase. 7AI(WW), 7AI(WA), 7AI(AW) and 7AI(AA) clusters (W, water and A, ammonia) show very high probability of the excited-state triple proton transfer (ESTPT) occurrence in ranges from 20% for 7AI(WA) to 60% for 7AI(AW), respectively. Furthermore, 7AI(AW) clusters with ammonia placed near N–H of 7AI has the highest probability among other isomers. In 7AI with three molecules of bridged-planar of water, ammonia and mixed water–ammonia clusters, the excited-state quadruple proton transfer reactions occur ineffectively and rearrangement of hydrogen-bonded network on solvents also takes place prior to either ESTPT or excited-state double proton transfer. The role played by mixed-solvent is revealed with replacing H₂O with NH₃ in which the ESMPT is found to be more efficient corresponding to lower barrier in the excited state. The preferential number of solvent surrounding 7AI that facilitates the proton transfer process is two for methanol and water but this preferential number for ammonia is one.

Highlights: (i) replacing H₂O with NH₃ assists ESPT corresponding to lower barrier in the excited state; (ii) the ESMPT time of 7AI with mixed water–ammonia is in the sub-picosecond timescale; (iii) the PT tends to be concerted process with at least one ammonia, but synchronous without ammonia.     

Ecological total-factor energy efficiency of China’s energy intensive industries

This paper uses a meta-frontier slack-based DEA model to measure the ecological total-factor energy efficiency as well as the energy conservation potential of China’s four energy intensive subsectors. We incorporate both desirable and undesirable output together in the period, 2000–2013. The conclusions are: firstly, under the meta-frontier, the four subsectors of energy intensive industries have low average level of ecological total-factor energy efficiencies. They are 0.137, 0.212, 0.238, and 0.307 in the non-metallic mineral products manufacturing industry, raw chemical materials and chemical products manufacturing industry, smelting and pressing of ferrous metals industry, and smelting and pressing of non-ferrous metals industry, respectively. Secondly, the ecological energy efficiency in East China is the highest among three regions. Central China and West China are behind, but they are extremely close to each other. Thirdly, East China almost has no technology gap pertaining to energy efficiency, while Central China and West China almost have the same gap. Finally, Sichuan is considered to be the best province in West China under group frontier due to its perform in the three energy intensive subsectors. For Central and East China, no province has higher ecological energy efficiency in more than two energy intensive subsectors.