On wear resistance of tool steel

Maintaining a reasonably low cutting tool wear when producing forming tools is a general challenge in the development of new forming tool materials. The tool life of a hot forming tool steel (H13) has been significantly improved by reducing its Si-content from 1.0 to 0.06 wt.%. However, this modified H13 (MH13) also displays a reduced cutting tool life due to higher cutting forces and a stronger tendency to form built up layers (BUE) on the cutting edge. This paper explains why.Gleeble tests of MH13 revealed a significantly higher flow stress in the 820–900 °C temperature interval in MH13 compared to H13. Thermo-Calc simulations showed that when reducing the Si-content from 1.0 to 0.06 wt.% the initial temperature for ferrite-to-austenite transformation (A1) was reduced from 900 °C to 820 °C. Knowing that austenite has totally different mechanical and thermal properties than ferrite, the difference in A1 between the two steels explains the higher cutting forces and higher tendency for BUE-formation. The conclusion is that the difference in machinability between H13 and MH13 is primarily related to their difference in A1.An attempt was also made to find a new tool material composition that can combine the wear resistance of MH13 and the good machinability of H13. Thermo-Calc simulations were performed with slightly modified alloying content without changing its properties as a good forming tool material, with the aim to increase A1. For instance, reducing the Mn content from 0.5 to 0.05 wt.% proved to increase A1 from 820 to 850 °C.     

Process modification in the scouring process of textile industry

The effects of scouring parameters on the scouring efficiency, including the weight ratio of de-sizing agent and fabric (5–80 g/g fabric), temperature of de-sizing agent tank (60–90 °C) and dipping time (2–8 s), were investigated. The results demonstrated that weight loss of sizing agent was significantly observed only in the de-sizing agent tank particularly in the first de-sizing tank and was found to a small extent in water tank. The optimum condition in the scouring machine was found at a de-sizing agent to fabric ratio of 20 g/g fabric, with a temperature of the first de-sizing agent tank of 80 °C, a temperature of the second de-sizing agent tank of 90 °C, and dipping time of fabric of 7 s. According to these conditions, more than 89% of the sizing agent was eliminated and only 3.52 mg/g fabric of sizing agent remained in the scoured fabric which was in an acceptable range for feeding to the down stream process known as dyeing process. Application of our results to actual textile plant has shown that there is a cost reduction due to improved utilization of rinse water, chemicals and energy in the process and consequent decreases in the generation of wastewater. Furthermore, the production capacity was increased from 30 m/min to 34.4 m/min.     

A comparative study on the effect of GTAW processes on the microstructure and mechanical properties of P91 steel weld joints

Modified 9Cr-1Mo (P91) steel is widely used in the construction of power plant components. In the present study, a comparative study on influence of activated flux tungsten inert gas (A-TIG), and gas tungsten arc (GTA) welding processes on the microstructure and the impact toughness of P91 steel welds was carried out. P91 steel welds require a minimum of 47 J during the hydrotesting of vessels as per the EN1557: 1997 specification. Toughness of P91 steel welds was found to be low in the as-weld condition. Hence post-weld heat treatment (PWHT) was carried out on weld with the objective of improving the toughness of weldments. Initially as per industrial practice, PWHT at 760 °C – 2 h was carried out in order to improve the toughness of welds. It has been found that after PWHT at 760 °C – 2 h, GTA weld (132 J) has higher toughness than the required toughness (47 J) as compared with A-TIG weld (20 J). The GTA weld has higher toughness due to enhanced tempering effects due to multipass welding, few microinclusion content and absence of δ-ferrite. The A-TIG weld requires prolonged PWHT (i.e. more than 2 h at 760 °C) than GTA weld to meet the required toughness of 47 J. This is due to harder martensite, few welding passes that introduces less tempering effects, presence of δ-ferrite (0.5%), and more alloy content. After PWHT at 760 °C – 3 h, the toughness of A-TIG weld was improved and higher than the required toughness of 47 J.     

Recycling thin film transistor liquid crystal display (TFT-LCD) waste glass produced as glass–ceramics

The waste electrical and electronic equipment (WEEE) directives are designed to deal with the rapidly increasing waste stream comprised of electrical and electronic equipment. Recycling electrical and electronic equipment reduces the quantity of waste going to final disposal. The demand for thin film transistor liquid crystal display (TFT-LCD) panels, commonly used in everyday electronic products, is increasing. Conventionally adopted treatments of TFT-LCD waste glass cannot meet WEEE directives. This study adopts the following operating conditions in fabricating glass–ceramics: sintering temperature of 800–950 °C; sintering time of 6 h; and, temperature increase rate of 5 °C/min. The glass–ceramic samples then underwent a series of tests, including the Vickers hardness, water absorption and porosity tests, to determine product quality. The Vickers hardness was 12.1 GPa when fired at 900 °C for 6 h, and density was 2.4 g/cm³ and water absorption was 0%. Thus, TFT-LCD waste glass can be regarded as a good glass–ceramic material.     

Using supercritical carbon dioxide as solvent to replace water in polyethylene terephthalate (PET) fabric dyeing procedures

Dyeing fabrics in supercritical carbon dioxide (SCD) instead of water can save energy, reduce water use and prevent pollution. The special pilot plant was designed to test dyeing procedures in supercritical carbon dioxide and the analyses of the results indicate major benefits as compared to water based procedures. The dyeing of polyethylene terephthalate (PET) fabric in supercritical carbon dioxide using special pilot plant was investigated. Disperse dye, C.I. (color index) Disperse Blue 79, was used in this study. After dyeing, rinsing in supercritical carbon dioxide, which removes the excess dyes, was also discussed. At the same dyeing conditions, K/S (color yield) of dyed fabric significantly increased with increasing the dye concentration from 1% o.w.f. (on weight of fabric) to 5% o.w.f. Dyeing temperature and pressure had a strong influence on the color yield. When the temperature rose above 110 °C, the increase in color yield was obvious. At 20 MPa, 120–130 °C, dyeing reached equilibrium after 60 min. The excess dye of the dyed PET fabric was small. The suitable condition in supercritical carbon dioxide for removal of excess dye from the dyed fabric was 70 °C, 20 MPa. The PET fabric dyed in supercritical carbon dioxide had good fastness and physical properties.     

Metal-cored arc welding process for joining of modified 9Cr-1Mo (P91) steel

In the present work, metal-cored arc welding process was used for joining of modified 9Cr-1Mo (P91) steel. Metal-cored arc welding process is characterized by high productivity, slag-free process, defect-free weldments that can be produced with ease, and good weldability. Toughness is essential in welds of P91 steel during hydro-testing of vessels. There is a minimum required toughness of 47 J for welds that has to be met as per the EN1557:1997 specification. In the present study, welds were completed using two kinds of shielding gases, each composition being 80% Argon + 20% CO₂, and pure argon respectively. Microstructural characterization and toughness evaluation of welds were done in the as – weld, PWHT at 760 °C – 2 h and PWHT at 760 °C – 5 h conditions. The pure argon shielded welds (‘A2’ and ‘B2’) have higher toughness than 80% argon + 20% CO₂ shielded welds (‘A1’ and ‘B1’). Pure argon shielded welds show less microinclusion content with low volume fraction of δ-ferrite (<2%) phase. Themo-calc windows (TCW) was used for the prediction of equilibrium critical transformation points for the composition of the welds studied. With increase in post-weld heat treatment (PWHT) duration from 2 h to 5 h, there was increase in toughness of welds above 47 J. Using metal-cored arc welding process, it was possible to achieve the required toughness of more than 47 J after PWHT at 760 °C – 2 h in P91 steel welds.     

Hermetic joining of 316L stainless steel using a patterned nickel nanoparticle interlayer

This paper evaluates the use of a nickel nanoparticle (NiNP) interlayer for making hermetic joints in 316L stainless steel substrates via diffusion brazing. Different NiNP inks were prepared using commercial nanopowder (～9 nm) and in-house synthesized nanoparticles. Syringe pump deposition of ～9 nm NiNP ink and diffusion brazing at 900 °C for 30 min under 2 MPa resulted in a hermetic joint up to the tested pressure of 70 psi. In-house synthesis of NiNPs was carried out in ethylene glycol by the reduction of NiCl₂·6H₂O in the presence of hydrazine (N₂H₄) as a reducing agent. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) results confirm the presence of pure fcc-Ni with an average particle size of 5.4 ± 0.9 nm. An as-synthesized suspension of NiNPs was patterned onto 316L stainless steel laminae via automated dispensing to a thickness of ～3 μm and bonded at 800 °C for 30 min at a pressure of 2 MPa. The diffusion-brazed test article was also found to be hermetic up to 70 psi. An examination of the bond line using scanning electron microscopy (SEM) showed good uniformity and continuity.     

The Satoyama Index: A biodiversity indicator for agricultural landscapes

Agricultural development to meet rapidly growing demands for food and biofuel and the abandonment of traditional land use have had major impacts on biodiversity. Habitat diversity is one of the most important factors influencing biodiversity in agricultural landscapes. In this study we propose an ecological index of ecosystem or habitat diversity in agricultural landscapes – the Satoyama Index (SI) – that is discernible under appropriate spatial units (e.g., 6 km × 6 km) from 1 km × 1 km gridded land-cover data available from an open-access web site. A high SI value is an indicator of high habitat diversity, which is characteristic of traditional agricultural systems, including Japanese satoyama landscapes, while a low value indicates a monotonic habitat condition typical of extensive monoculture landscapes. The index correlated well with the spatial patterns of occurrence of a bird of prey (Butastur indicus) and species richness of amphibians and damselflies in Japan. The values of the SI also corresponded well to the spatial patterns of typical traditional agricultural landscapes with high conservation value in other countries, for example, the dehesas of the Iberian Peninsula and shade coffee landscapes in Central America. Globally, the pattern of East/South-East Asian paddy belts with their high index values contrasts markedly with the low values of the Eurasian, American, and Australian wheat or corn belts. The SI, which correlates landscapes with biodiversity through potential habitat availability, is highly promising for assessing and monitoring the status of biodiversity irrespective of scale.     

Effects of different diets on utilization of nitrogen from cattle slurry applied to grassland on a sandy soil in The Netherlands

Dietary adjustments have been suggested as a means to reduce N losses from dairy systems. Differences in fertilizing value of dairy slurry as a result of dietary adjustments were evaluated in a 1-year grassland experiment and by long-term modelling. Slurry composition of non-lactating dairy cows was manipulated by feeding diets with extreme high and low levels of dietary protein and energy. C:N_total ratio of the produced slurries ranged from 5.1 to 11.4. To evaluate their short-term fertilizer N value, the experimental slurries (n = 8) and slurries from commercial farms with variable composition (n = 4), were slit-injected in two grassland fields on the same sandy soil series in the north of The Netherlands (53°10′N, 6°04′E), with differences in sward age and ground water level. The recently established grassland field (NEW) was characterized by lower soil OM, N and moisture contents, less herbs and more modern grass varieties compared to the older grassland field (OLD). Slurry was applied in spring (100 kg N ha⁻¹) and after the first cut (80 kg N ha⁻¹) while in total four cuts were harvested. Artificial fertilizer N treatments were included in the experiment to calculate the mineral fertilizer equivalent (MFE) of slurry N. The OLD field showed a higher total N uptake whereas DM yields were similar for the two fields. Average MFE of the slurries on the OLD field (47%) was lower than on the NEW field (56%), probably as a result of denitrification of slurry N during wet conditions in spring. Slurries from high crude protein diets showed a significantly higher MFE (P < 0.05) compared to low crude protein diets. No significant differences in MFE were observed between slurries from high and low energy diets. On both fields, MFE appeared to be positively related to the ammonium content (P < 0.001) and negatively to the C:N_total ratio of the slurry DM (P = 0.001). Simulation of the effect of long-term annual application of 180 kg N ha⁻¹ with highest and lowest C:N_total ratio suggested that both slurries would lead to an increase in annual soil N mineralization. Both soil N mineralization and SOC appeared to be substantially higher in equilibrium state for the slurry with the highest C:N_total ratio. It is concluded that in a situation with slit-injection, the reduced first-year N availability of slurry with a high C:N_total ratio as observed in the grassland experiment will only be compensated for by soil N mineralization on the very long term.     

Lodging in rice can be alleviated by atmospheric CO2 enrichment

The projected increase of atmospheric CO₂ concentration [CO₂] is expected to increase yield of agricultural C₃ crops, but little is known about effects of [CO₂] on lodging that can reduce yield. This study examined the interaction between [CO₂] and nitrogen (N) fertilization on the lodging of rice (Oryza sativa L.) using free-air CO₂ enrichment (FACE) systems installed in paddy fields at Shizukuishi, Iwate, Japan (39°38′N, 140°57′E). Rice plants were grown under two levels of [CO₂] (ambient = 365 μmol mol⁻¹; elevated [CO₂] = 548 μmol mol⁻¹) and three N fertilization regimes: a single initial basal application of controlled-release urea (8 g N m⁻², CRN), split fertilization with a standard amount of ammonium sulfate (9 g N m⁻², MN), and ample N (15 g N m⁻², HN). Lodging score (six ranks at 18° intervals, with larger scores indicating greater bending), yield, and yield components were measured at maturity. The lodging score was significantly higher under HN than under CRN and MN, but lodging was alleviated by elevated [CO₂] under HN. This alleviation was associated with the shortened and thickened lower internodes, but was not associated with a change in the plant's mass moment around the culm base. A positively significant correlation between lodging score and ripening percentage indicated that ripening percentage decreased by 4.5% per one-unit increase in lodging score. These findings will be useful to develop functional algorithm that can be incorporated into mechanistic crop models to predict rice production more accurately in a changing climate and with different cultural practices.     

Innovative cleaner production for steel phosphorization using Zn–Mn phosphating solution

Phosphating prior to coating for steel is usually needed. In this paper, an innovative cleaner production has been developed for steel surface treatment using Zn–Mn phosphating solution in which there was no nitrite. The mass of the Zn–Mn layer deposited in this new process was about 1.1 g m^?2 when the temperature ranged from 3 to 35 °C. The corrosion time for the color phosphating layer in the copper sulfate spot test was in the range of 72–145 s. Adhesion test showed that the coating layers achieved a higher adhesion load than those produced by conventional methods. Washing using water was not necessary in this cleaner phosphorization, which usually follows phosphorization in traditional processes of steel phosphorization. Consequently, wastewater discharge was reduced greatly.     

Analysis of temperature effects on seasonal and interannual variation in CH4 emission from rice-planted pots

Rice (Oryza sativa L.) paddies are one of the major sources of atmospheric methane (CH₄), a greenhouse gas. To elucidate the quantitative relationship between CH₄ emission from rice paddies and temperature, 6 years data of CH₄ emission from pot experiments were analyzed in terms of the sum of effective temperature (∑(T−15); T is the daily mean air temperature (°C)). The base temperature of 15 °C was adopted as the 0 °C physiological temperature for methanogens. Significant positive correlations between total CH₄ emission throughout the rice growth period and ∑(T−15) were observed for pots with rice straw (RS) application at a rate of 6 g kg⁻¹ soil, which corresponds to 6 t ha⁻¹ (r=0.830⁷¹), and those without RS application (r=0.818⁷¹). It was confirmed that temperature is a major factor affecting the interannual variation in CH₄ emission. For the 1993 and 1995 data sets that include seven and four levels of RS application, the relationship between seasonal CH₄ emission and RS application rate could be expressed using linear functions (r=0.988⁷¹, 0.996⁷¹), the slopes of which were similar to each other. Based on these findings, we confirmed that the dependence of seasonal CH₄ emission on both temperature and RS application rate can be described by a single linear equation.     

Modeling increased demand of energy for air conditioners and consequent CO2 emissions to minimize health risks due to climate change in India

Developing countries situated mostly in latitudes that are projected for the highest climate change impact in the twenty-first century will also have a predictable increase in demand on energy sources. India presents us with a unique opportunity to study this phenomenon in a large developing country. This study finds that climate adaptation policies of India should consider the significance of air conditioners (A/Cs) in mitigation of human vulnerability due to unpredictable weather events such as heat waves. However, the energy demand due to air conditioning usage alone will be in the range of an extra ～750,000 GWh to ～1,350,000 GWh with a 3.7 °C increase in surface temperatures under different population scenarios and increasing incomes by the year 2100. We project that residential A/C usage by 2100 will result in CO₂ emissions of 592 Tg to 1064 Tg. This is significant given that India's total contribution to global CO₂ emissions in 2009 was measured at 1670 Tg and country's residential and commercial electricity consumption in 2007 was estimated at 145,000 GWh.     

Insight into the distribution of metallic elements in membrane bioreactor: Influence of operational temperature and role of extracellular polymeric substances

The distribution of metallic elements in a submerged membrane bioreactor(MBR) was revealed at different temperatures using inductively coupled plasma-optical emission spectrometry(ICP-OES), and the role of extracellular polymeric substances(EPS) was probed by integrating scanning electron microscopy(SEM) with confocal laser scanning microscopy(CLSM) over long-term operation. More metallic elements in the influent were captured by suspended sludge and built up in the fouling layer at lower temperature. The concentration of metallic elements in the effluent was 5.60 mg/L at 10°C operational temperature, far lower than that in the influent(51.35 mg/L). The total contents of metallic elements in suspended sludge and the membrane fouling layer increased to 40.20 and 52.19 mg/g at 10°C compared to 35.14 and 32.45 mg/g at 30°C, and were dominated by the organically bound fraction. The EPS contents in suspended sludge and membrane fouling layer sharply increased to 37.88 and 101.51 mg/g at 10°C, compared to 16.87 and 30.03 mg/g at 30°C. The increase in EPS content at lower temperature was responsible for the deposition of more metallic ions. The strong bridging between EPS and metallic elements at lower temperature enhanced the compactness of the fouling layer and further decreased membrane flux. This was helpful for understanding the mechanism of membrane fouling at different operational temperatures and the role of EPS, and also of significance for the design of cleaning strategies for fouled membranes after long-term operation.     

Reduction of hexavalent chromium by polypyrrole-modified steel mesh electrode

Adherent polypyrrole (ppy) films were electropolymerized from a para-toluenesulfonic sodium (PTS) solution on stainless steel mesh (SSM). Reduced ppy-modified SSM electrode can transfer Cr(VI) to Cr(III) effectively. Lower pH (<2) or higher temperature (>35 °C) is beneficial for the removal of Cr(VI). Electro-reduction achieved 90% removal efficiency after 21 min by cyclic voltammetry. The removal efficiency is 96–56% for one–six contact cycles between ppy and Cr(VI). SEM shows that ppy films on SSM have regular morphology with small nucleus of less than 1 μm in diameter.     

Biodiversity,carbon stocks and sequestration potential in aboveground biomass in smallholder farming systems of western Kenya

While Carbon (C) sequestration on farmlands may contribute to mitigate CO₂ concentrations in the atmosphere, greater agro-biodiversity may ensure longer term stability of C storage in fluctuating environments. This study was conducted in the highlands of western Kenya, a region with high potential for agroforestry, with the objectives of assessing current biodiversity and aboveground C stocks in perennial vegetation growing on farmland, and estimating C sequestration potential in aboveground C pools. Allometric models were developed to estimate aboveground biomass of trees and hedgerows, and an inventory of perennial vegetation was conducted in 35 farms in Vihiga and Siaya districts. Values of the Shannon index (H), used to evaluate biodiversity, ranged from 0.01 in woodlots through 0.4–0.6 in food crop plots, to 1.3–1.6 in homegardens. Eucalyptus saligna was the most frequent tree species found as individual trees (20%), in windrows (47%), and in woodlots (99%) in Vihiga and the most frequent in woodlots (96%) in Siaya. Trees represented the most important C pool in aboveground biomass of perennial plants growing on-farm, contributing to 81 and 55% of total aboveground farm C in Vihiga and Siaya, respectively, followed by hedgerows (13 and 39%, respectively) and permanent crop stands (5 and 6%, respectively). Most of the tree C was located in woodlots in Vihiga (61%) and in individual trees growing in or around food crop plots in Siaya (57%). The homegardens represented the second C pool in importance, with 25 and 33% of C stocks in Vihiga and Siaya, respectively. Considering the mean total aboveground C stocks observed, and taking the average farm sizes of Vihiga (0.6 ha) and Siaya (1.4 ha), an average farm would store 6.5 ± 0.1 Mg C farm^?1 in Vihiga and 12.4 ± 0.1 Mg C farm^?1 in Siaya. At both sites, the C sequestration potential in perennial aboveground biomass was estimated at ca. 16 Mg C ha^?1. With the current market price for carbon, the implementation of Clean Development Mechanism Afforestation/Reforestation (CDM A/R) projects seems unfeasible, due to the large number of small farms (between 140 and 300) necessary to achieve a critical land area able to compensate the concomitant minimum transaction costs. Higher financial compensation for C sequestration projects that encourage biodiversity would allow clearer win–win scenarios for smallholder farmers. Thus, a better valuation of ecosystem services should encourage C sequestration together with on-farm biodiversity when promoting CDM A/R projects.     

Soil C storage as affected by tillage and straw management: An assessment using field measurements and model predictions

Soil tillage and straw management are both known to affect soil organic matter dynamics. However, it is still unclear whether, or how, these two practices interact to affect soil C storage, and data from long term studies are scarce. Soil C models may help to overcome some of these problems. Here we compare direct measurements of soil C contents from a 9 year old tillage experiment to predictions made by RothC and a cohort model. Soil samples were collected from plots in an Irish winter wheat field that were exposed to either conventional (CT) or shallow non-inversion tillage (RT). Crop residue was removed from half of the RT and CT plots after harvest, allowing us to test for interactive effects between tillage practices and straw management. Within the 0–30 cm layer, soil C contents were significantly increased both by straw retention and by RT. Tillage and straw management did not interact to determine the total amount of soil C in this layer. The highest average soil C contents (68.9 ± 2.8 Mg C ha^?1) were found for the combination of RT with straw incorporation, whereas the lowest average soil C contents (57.3 ± 2.3 Mg C ha^?1) were found for CT with straw removal. We found no significant treatment effects on soil C contents at lower depths. Both models suggest that at our site, RT stimulates soil C storage largely by decreasing the decomposition of old soil C. Extrapolating our findings to the rest of Ireland, we estimate that RT will lead to C mitigation ranging from 0.18 to 1.0 Mg C ha^?1 y^?1 relative to CT, with the mitigation rate depending on the initial SOC level. However, on-farm assessments are still needed to determine whether RT management practices can be adopted under Irish conditions without detrimental effects on crop yield.     

Second generation diesel fuel from renewable sources

The study is devoted to the issue of direct transformation of triacylglycerols (TAG) to diesel fuels applying a commercially available NiMo and NiW hydrorefining catalysts. It was proved that during hydrodesulphurisation also hydrodeoxygenation occurs and TAG can be converted to the fuel biocomponent by adding 6.5 % vol. of TAG to atmospheric gas oil. In this way, after hydroprocessing at mild conditions (temperature 320–360 °C, pressure 3.5–5.5 MPa, LHSV: 1.0 h^?1 and ratio H₂:HC = 500–1000 Nm³/m³, catalyst presence), gas oil containing 5–5.5% of biocomponent was prepared, characterized with standard performance and emission parameters. Performance and emission tests documented that even 5% vol. portion of bio-components reduces the controlled and uncontrolled emissions.     

A promising clean process for production of diosgenin from Dioscorea zingiberensis C. H. Wright

This study proposes a new approach for diosgenin production from Dioscorea zingiberensis C. H. Wright tubers with respect to resources utilization and clean production. This process consisted of two successive parts, i.e., recovery of starch from raw material, and microbial hydrolysis of the residue to produce diosgenin by Trichoderma reesei. In the first step, about 75.4% of hemicellulose and 98.0% of starch were removed from the tubers. In the second step, about 90.2% of diosgenin was released from saponins by T. reesei at 30 °C, at an aeration of 0.80 vvm and agitation rate of 300 rpm in a 5.0 L bioreactor. Significant reduction of pollutant production was detected by replacing the traditional approach with the proposed new method. About 99.2% of reducing sugar, 99.4% of chemical oxygen demand, 99.2% of total organic carbon, 100% of SO₄^2?, and 100% of acid was reduced in the new processing wastewater.     

Performance and water-use efficiency (single-leaf vs. whole-canopy) of well-watered and half-stressed split-root Lambrusco grapevines grown in Po Valley (Italy)

‘Lambrusco a foglia frastagliata’ grapevines (Vitis vinifera L.) were grown outdoors at Piacenza (44°55′N, 9°44′E, Po Valley, Italy) with the root system split between two 30-L pots and subjected from pre-veraison (17 July) to harvest (5 September) to soil drying of half of the root system (HS) induced by withholding water from one of the two pots as compared to well-watered (WW) vines (both pots daily recharged at field capacity). Volumetric soil-water content, pre-dawn and mid-morning leaf water potential, single-leaf gas-exchange as assimilation rate, stomatal conductance and transpiration were monitored throughout the trial. Whole-canopy gas-exchange as net CO₂ exchange rate (NCER) and transpiration were tracked from 31 August to 7 September on three vines per treatment on a 24-h basis using an enclosure method. Primary leaf carbon isotope (δ¹³C) composition, yield components and must composition were determined at harvest.Withdrawing water from one pot triggered a water stress response showing higher stomatal sensitivity to changes in air vapour pressure deficit, relatively low assimilation rates, high intrinsic and extrinsic water-use efficiency (WUE) and earlier cessation of shoot growth. Yet, mid-morning leaf water potential was consistently lower in HS treatment over stress as compared to WW, indicating an anisohydric adjustment. Canopy NCER given on a leaf-area basis showed mean daily rates ranging from 3.9 to 4.9 μmol m² s^?1 in WW canopies against 2.6–3.0 μmol m^?2 s^?1 in HS. Conversely, canopy transpiration rates varied from 0.915 to 1.157 mmol m^?2 s^?1 for WW to 0.630–0.714 mmol m² s^?1 in HS. Increased leaf-based intrinsic and extrinsic WUE in HS did not match the canopy response, which to some extent resulted in an opposite outcome, i.e. higher canopy WUE in well-watered vines especially in the morning hours. Likewise, δ¹³C did not differ between treatments. This suggests caution when point-time determinations of single-leaf-based WUE are extrapolated to the whole-canopy behaviour when assessing the water saving strategies of a given genotype. The stressed vines achieved no variation in yield level and components and had improved grape composition as to soluble solids and total anthocyanins. This optimal behaviour is likely due to earlier shoot growth cessation, enhanced maturity and a buffering leaf-to-fruit ratio (3.61 m² kg^?1) that mitigated the effects of post-veraison stress.