Total Boundary Length Research Articles

CadastreVision: A benchmark dataset for cadastral boundary delineation from multi-resolution earth observation images

Approximately 70%–75% of people worldwide have no formally registered land rights. Fit-For-Purpose Land Administration was introduced to address this problem and focuses on delineating visible cadastral boundaries from earth observation imagery. Recent studies have shown the potential of deep learning models to extract these visible cadastral boundaries automatically. However, studies are limited by the small size and geographical coverage of available datasets and by the lack of information about which cadastral boundaries are visible, i.e., associated with a physical object boundary. To overcome these problems, we present CadastreVision, a benchmark dataset containing cadastral reference data and corresponding multi-resolution earth observation imagery from The Netherlands, with a spatial resolution ranging from 0.1 m to 10 m. The ratio between visible and non-visible cadastral boundaries is essential to evaluate the potential automation level in cadastral boundary extraction from earth observation images and interpret results obtained by deep learning models. We investigate this ratio using a novel analysis pipeline that overlays cadastral reference data with visible topographic object boundaries. Our results show that approximately 72% of the total length of cadastral boundaries in The Netherlands are visible. CadastreVision will enable new developments in cadastral boundary delineation and future endeavours to investigate knowledge transfer to data-scarce areas. Our data and code is available at https://github.com/jeroengrift/cadastrevision.

Pulsed current-assisted twelve-roll precision rolling deformation of SUS304 ultra-thin strips with exceptional mechanical properties

Innovative pulsed current-assisted multi-pass rolling tests were conducted on a 12-roll mill during the rolling deformation processing of SUS304 ultra-thin strips. The results show that in the first rolling pass, the rolling reduction rate of a conventionally rolled sample (at room temperature) is 33.8%, which can be increased to 41.5% by pulsed current-assisted rolling, enabling the formation of an ultra-thin strip with a size of 67.3 μm in only one rolling pass. After three passes of pulsed current-assisted rolling, the thickness of the ultra-thin strip can be further reduced to 51.7 μm. To clearly compare the effects of a pulsed current on the microstructure and mechanical response of the ultra-thin strip, ultra-thin strips with nearly the same thickness reduction were analyzed. It was found that pulsed current can reduce the degree of work-hardening of the rolled samples by promoting dislocation detachment, reducing the density of stacking faults, inhibiting martensitic phase transformation, and shortening the total length of grain boundaries. As a result, the ductility of ultra-thin strips can be effectively restored to approximately 16.3% while maintaining a high tensile strength of 1118 MPa.Therefore, pulsed current-assisted rolling deformation shows great potential for the formation of ultra-thin strips with a combination of high strength and ductility.

Cold spraying of Al-5Si/Al2O3 composite coatings on AZ31 Mg alloy: Microstructure, adhesion strength, and tribological properties

To improve the wear resistance of commercial AZ31 Mg alloy, two types of dense and thick composite coatings were prepared on AZ31 Mg alloy by means of cold-spray technology. For this purpose, Al2O3 particles with different morphology (round and irregular) were separately added to the Al5Si feedstock. The morphological effects of Al2O3 on the microstructure, adhesion strength, hardness, and tribological properties of the coatings were comprehensively studied. Microstructural features of the coatings were examined by means of optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD). The analysis reveals that most of the grains in both coatings are ultrafine, and approximately half of the total grain boundary length is composed of low-angle grain boundaries. Wear, hardness, and pull-off tests showed that both types of Al2O3 particles have a positive impact on porosity, adhesion, hardness, and wear resistance of the composite coatings. Compared to round Al2O3, irregular Al2O3 particles exhibit better retention in the coating, thereby resulting in a higher hardness and wear resistance.

The influence of processing methods on creep of wrought and additively manufactured CrCoNi multi-principal element alloys

The influence of vacuum arc melting and mechanical processing (wrought) versus additive manufacturing (AM) on the creep behavior of multi-principal element alloys (MPEA) is investigated in this study. Annealed wrought and hot isostatically pressed (HIP) AM CrCoNi were creep tested under constant tensile stress of 40 to 200 MPa at temperatures of 1023 to 1173 K. Stress exponents of 4.5 ± 0.2 and 5.9 ± 0.1 and activation energies ranging from 240 to 259 and 320 to 331 kJ/mol were found for wrought and AM CrCoNi, respectively. The results indicate that the AM material exhibits superior creep resistance and inferior creep ductility compared to the wrought alloy. This difference is attributed to the AM material having a higher percentage of Cr-rich oxides, a smaller total low angle grain boundary (LAGB) length on a percentage basis, and a greater total twin boundary (TB) length on a percentage basis. The AM and wrought materials have similar grain sizes; however, the smaller LAGB length and greater TB length in the AM material reduce slip transmission on the other side of the boundaries and contribute to strength. The dislocation structures of the AM and wrought materials consist of individual curved dislocations with dislocation multijunctions and jogs, which is similar to the arrangements previously observed in CrMnFeCoNi.

Rock slope failure preparation paced by total crack boundary length

Gravitational mass wasting prediction requires understanding of the factors controlling failure. Prior to slope failure, cracks in the weakened rock are thought to grow and coalesce, eventually forming a continuous failure plane. Here, we apply a hidden Markov machine learning model to seismic data, revealing the temporal evolution of cracks prior to a major rockslide event in the Swiss Alps. After prolonged linear increase of the crack cumulative number, an S-shaped crack rate pattern occurred in the day before the rockslide. A simple mechanistic model can explain this behaviour, showing that total crack boundary length is the key factor controlling failure plane evolution immediately before mass movement. Our findings imply that cracks should be treated as 2-D, rather than 1-D objects, and that slope failure can be driven predominantly by internal rather than external processes. Our model offers a novel, physically based approach for early warning of slope failures.

Accounting for functional connectivity in cross-realm conservation planning in a data poor context: The Cyprus case

In the past years, efforts have been made to include connectivity metrics in conservation planning in order to promote and enhance well-connected systems of protected areas. Connectivity is particularly important for species that rely on more than one realm during their daily or life cycle (multi-realm species). However, conservation plans for the protection of multi-realm species usually involve a single realm, excluding other realms from the prioritization process. Here, we demonstrate an example of cross-realm conservation planning application for the island of Cyprus by taking into account the terrestrial and marine realms and their interface (i.e. coast). Operating within a data-poor context, we use functional connectivity metrics to identify priority areas for the conservation of six multi-realm species, by setting conservation targets simultaneously for the terrestrial and marine realms. MARXAN decision-support tool was used for the identification of the priority areas.Four scenarios were developed to evaluate the impacts of including connectivity in the prioritization process and the effectiveness of the existing coastal/marine protected areas in the achievement of the conservation targets set for the species. All scenarios considered land and sea anthropogenic uses as surrogate costs to influence the prioritization process.Our findings show an increase in the area of the reserve network and, therefore, the cost, when connectivity is included, whilst reducing the total boundary length. Furthermore, the current reserve network fails to achieve conservation targets, particularly for the marine part, which has a substantially smaller protection coverage than the terrestrial part.We conclude that focus should be given in the expansion of the current coastal/marine reserve network following a cross-realm conservation approach. This approach is not only relevant for the conservation of multi-realm species, but also for islandscapes, in particular, where the interdependence between the hinterland and the coast is larger and therefore the magnitude of the impacts generated in one realm and affects the other.

Effect of Ca/Al ratio on hot tearing susceptibility of Mg–Al–Ca alloy

The hot tearing susceptibility (HTS) of Mg–xAl–yCa (x + y = 8) alloys with different Ca/Al ratios (namely 0.06, 0.34, 0.63, 1.04, 1.75, and 2.82) is experimentally investigated using a “T-shaped” hot tearing measuring system. Additionally, the HTS of the alloys is determined using an optimized version of the Clyne–Davies model in conjunction with the solidification parameters of the alloys. The results of the optimized model, i.e., the fact that the HTS decreases with the increase in the Ca/Al ratio, are in good agreement with both the numerical simulations and experimental results. Furthermore, the hot tearing curves, thermal analysis curves, and microstructure of the alloys show that with the increase in the Ca/Al ratio, the intergranular bonding before the hot tearing initiation changes from relying on a liquid film only to involving both intergranular bridging and the liquid film, which enhances the intergranular bonding ability. In addition, the increase in the eutectic phase content, number of dendrite skeleton voids, and dendrite gap width result in an increase in the number of feeding channels and a decrease in the flow resistance of the residual liquid phase, thus increasing its filling efficiency against tears. Therefore, in alloys with high Ca/Al ratios, the large grain size results in a reduction in both the number and total length of grain boundaries, thereby reducing the number of locations where hot tears may initiate. Therefore, the HTS of alloys with a high Ca/Al ratio is significantly reduced.

Effect of surface burnishing process with different strain paths on the copper microstructure

The single strain path (SSP) and the reciprocating strain path (RSP) machining are performed on the sample surface with a multi-ball surface burnishing tool to study the effect of different deformation modes on the microstructure. The samples are characterized mechanically and metallographically via a microhardness tester, an optical microscope, and a backscattered scanning electron microscope. The effect of the two strain paths on the plastic strain in the material is explored by developing a numerical simulation model. The characterization and simulation results show that the deformation layer thicknesses are 79 μm, 208 μm, and 290 μm for the SSP treated samples and 108 μm, 191 μm, and 305 μm for the SSP models at penetration depths Dp of 30 μm, 60 μm, and 90 μm, and meantime, 195 μm, 249 μm and, 390 μm for the RSP treated samples and 146 μm, 248 μm, and 396 μm for the RSP models. Moreover, the RSP treated samples are harder than the SSP treated samples at the same penetration depth Dp, attributed to the smaller grain size and longer total length of grain boundaries of the RSP treated samples. The simulation results show that the RSP machining, with the assistance of the Bauschinger effect, further increases the strain degree and the machining influence depth in the sample compared with the SSP machining. The RSP machining disintegrates the dislocation cells in collaboration with the Bausinger effect, which causes the shielding effect of long-range stress to be significantly reduced, further transferring machining stress to the sample interior. It is the main reason why the RSP machining leads to deeper affecting depth. Furthermore, the grain boundaries in the fine-grain layer of the RSP and SSP treated samples are mainly dominated by high angle grain boundaries, supplemented by low angle grain boundaries, with a smaller percentage of twin boundaries, while in the coarse-grain layer are mainly twin boundaries, supplemented by high angle grain boundaries, with a smaller percentage of low angle grain boundaries. The micro-textures of the samples machined by the two strain paths are minor differences, but the grains in the subsurface layers produced different grain rotations.

SecSel, a new software tool for conservation prioritization that is applicable to ordinal-scale data for multiple biodiversity features.

SecSel, a protected-area prioritization tool, has been developed to help design areas that efficiently protect multiple features, including conservation of biodiversity and use of ecosystem services. The prioritization by SecSel is based on evaluation of the local units of each feature. The evaluation metrics should be quantitative but need not be ratio scale. The minimum requirement of the input data is that they are ordinal. The conservation target is the number of local units with high values of each feature to be protected in the area. SecSel can handle conflicts among features, including conflicts between conservation and utilization of land or specific ecosystem functions. Before the selection procedure, one of a conflicting pair of features in a site is discarded. That decision is based on the dispensability of the local unit to fulfilling the conservation target of each feature. SecSel also considers the cost of including each site in the protected area and the compactness of the area in terms of total boundary length or the distance to the nearest site. To demonstrate the functionality of Secsel, we used it to design land use in an alpine region of northern Japan where conservation of alpine vegetation and its recreational use are important considerations.

A conceptual methodology for site exclusion boundary and site large early release frequency for multi-unit nuclear power plants site

Probabilistic Safety Assessment (PSA) risk metrics Core Damage Frequency (CDF) and Large Early Release Frequency (LERF) are currently applied for single NPP unit. The purpose of the work is to arrive at quantitative value for LERF for a site consisting of many NPPs. For this objective, the work proposes to define an exclusion boundary for the whole site (site exclusion boundary) which is different from exclusion boundary for one NPP. At a site, the exclusion boundaries of the individual NPPs may overlap or can be separate. In the present research, various concepts of total exclusion boundary length for the site are delineated upon using the exclusion radius/boundary of individual NPPs. A case study for a hypothetical site consisting of three NPP units was considered for the demonstration of the proposed methodology. The NPPs have same power level and equal radius of exclusion boundary. LERF results are available for individual NPPs and those accident sequences are relevant that (initiating events are independent events or common cause events) that cause release of more than 4% of core I-131 radioactive nuclide within 10 h of accident. The radionuclide dispersion was calculated using Gaussian plume model for dose at various locations on the site exclusion boundary for the multiple NPP site. The calculation of site LERF was carried out for various locations on the site exclusion boundary for a specific configuration of NPPs at site.

Morphology and performance evolution of anode microstructure in solid oxide fuel cell: A model-based quantitative analysis

The morphological evolution caused by Ni coarsening is one of the main causes of performance degradation in solid oxide fuel cell (SOFC) anode. In this study, we perform a model-based quantitative analysis to investigate the influences of morphological evolution on SOFC performance and durability. A phase-field model is developed to track the temporal evolution of microstructure as inputs of an electrode numerical model for evaluating the electrochemical performance degradation over time. After model validation, parametric simulations are conducted. It is found that Ni coarsening manifests mainly in two aspects: the reduction of total three-phase boundary (TPB) length, and the lengthening of single TPB. Based on the quantified microstructure parameters, the overpotential increase caused by Ni coarsening is obtained. Besides, the results highlight the importance of Ni content on the temporal evolution. The performance analysis provides an optimal range of Ni content, which can maintain a relatively low overpotential during the whole process.

Morphological and non-equilibrium analysis of coupled Rayleigh–Taylor–Kelvin–Helmholtz instability

In this paper, the coupled Rayleigh–Taylor–Kelvin–Helmholtz instability (RTI, KHI, and RTKHI, respectively) system is investigated using a multiple-relaxation-time discrete Boltzmann model. Both the morphological boundary length and thermodynamic non-equilibrium (TNE) strength are introduced to probe the complex configurations and kinetic processes. In the simulations, RTI always plays a major role in the later stage, while the main mechanism in the early stage depends on the comparison of buoyancy and shear strength. It is found that both the total boundary length L of the condensed temperature field and the mean heat flux strength D3,1 can be used to measure the ratio of buoyancy to shear strength and to quantitatively judge the main mechanism in the early stage of the RTKHI system. Specifically, when KHI (RTI) dominates, LKHI > LRTI LKHI < LRTI, D3,1KHI>D3,1RTI D3,1KHI<D3,1RTI; when KHI and RTI are balanced, LKHI = LRTI, D3,1KHI=D3,1RTI, where the superscript “KHI (RTI)” indicates the type of hydrodynamic instability. It is interesting to find that (i) for the critical cases where KHI and RTI are balanced, both the critical shear velocity uC and Reynolds number Re show a linear relationship with the gravity/acceleration g; (ii) the two quantities, L and D3,1, always show a high correlation, especially in the early stage where it is roughly 0.999, which means that L and D3,1 follow approximately a linear relationship. The heat conduction has a significant influence on the linear relationship. The second set of findings are as follows: For the case where the KHI dominates at earlier time and the RTI dominates at later time, the evolution process can be roughly divided into two stages. Before the transition point of the two stages, LRTKHI initially increases exponentially and then increases linearly. Hence, the ending point of linear increasing LRTKHI can work as a geometric criterion for discriminating the two stages. The TNE quantity, heat flux strength D3,1RTKHI, shows similar behavior. Therefore, the ending point of linear increasing D3,1RTKHI can work as a physical criterion for discriminating the two stages.

Stored Energy Evaluation for High Strength Dual-Phase Steels with Different Pre-annealing Conditions

The purpose of this study was to determine the stored energy of dual-phase (DP) steels after hot rolling, coiling, and cold reduction using electron backscattered diffraction analysis. Three methods for stored energy evaluation were examined and compared: the sub-grain boundary, image quality, and kernel average misorientation methods. The results demonstrated that the sub-grain method, in which stored energy was calculated as a function of sub-grain boundary misorientations and total sub-grain boundary length, can provide more accurate stored energy values, since cold work was responsible for forming numerous dislocation structures such as shear bands, cells, and cell walls. As expected, the steels with the combination of a low coiling temperature of 580 °C and 60 pct cold reduction had the highest stored energy values. This information is important in defining how pre-anneal processing conditions might control the response of DP steels to the various transformations occurring during continuous galvanizing line simulations.

Spicule movement on RBCs during echinocyte formation and possible segregation in the RBC membrane

We use phase contrast microscopy of red blood cells to observe the transition between the initial discocyte shape and a spiculated echinocyte form. During the early stages of this change, spicules can move across the surface of the cell; individual spicules can also split apart into pairs. One possible explanation of this behaviour is that the membrane forms large scale domains in association with the spicules. The spicules are formed initially at the rim of the cell and then move at speeds of up to 3 μm/min towards the centre of the disc. Spicule formation that was reversed and then allowed to proceed a second time resulted in spicules at reproducible places, a shape memory effect that implies that the cytoskeleton contributes towards stopping the spicule movement. The splitting of the spicules produces a well-defined shape change with an increase in membrane curvature associated with formation of the daughter pair of spicules; the total boundary length around the spicules also increases. Following the model in which the spicules are associated with lipid domains, these observations suggest an experimental procedure that could potentially be applied to the calculation of the line tension of lipid domains in living cells.

Improvement in damping capacity of extruded pure magnesium through precompression and subsequent annealing: Effects of dislocation and twin boundary motions

Abstract This study demonstrates that a combined precompression and subsequent annealing (PCA) treatment considerably improves the damping capacity of extruded pure Mg. Variations in the microstructure and damping capacity with the annealing temperature of PCA are investigated. Precompression along the extrusion direction induces an increase in the dislocation density and the formation of numerous {10–12} twins, the latter of which results in significant lattice reorientation and an increased total boundary length. Subsequent annealing at 200 °C causes barely any change in the formed twin structure, whereas annealing above 250 °C induces extensive grain growth through strain-induced grain boundary migration; this consequently reduces the twin fraction and dislocation density and increases the grain size. The samples subjected to PCA show higher damping capacities than the initial sample in both low- and high-strain-amplitude regions. The improved damping capacity in the low-strain-amplitude region is due primarily to the increase in the dislocation density and Schmid factor for basal slip; namely, more abundant dislocations move more readily, which leads to dissipation of a larger amount of energy via the vibration and sweeping motion of dislocations. In the high-strain-amplitude region, a large sweeping motion of dislocations within grown grains and additional sweeping motion of twin boundaries within twinned grains significantly improve the damping capacity. However, PCA treatment with annealing at 200 °C causes a relatively smaller increment in the damping capacity in the high-strain-amplitude region because the excessive dislocations and twin boundaries in this sample hinder their motions.

Extraction of Yardang Characteristics Using Object-Based Image Analysis and Canny Edge Detection Methods

Parameters of geomorphological characteristics are critical for research on yardangs. However, methods which are low-cost, accurate, and automatic or semi-automatic for extracting these parameters are limited. We present here semi-automatic techniques for this purpose. They are object-based image analysis (OBIA) and Canny edge detection (CED), using free, very high spatial resolution images from Google Earth. We chose yardang fields in Dunhuang of west China to test the methods. Our results showed that the extractions registered an overall accuracy of 92.26% with a Kappa coefficient of agreement of 0.82 at a segmentation scale of 52 using the OBIA method, and the exaction of yardangs had the highest accuracy at medium segmentation scales (138, 145). Using CED, we resampled the experimental image subset to a series of lower spatial resolutions for eliminating noise. The total length of yardang boundaries showed a logarithmically decreasing (R2 = 0.904) trend with decreasing spatial resolution, and there was also a linear relationship between yardang median widths and spatial resolutions (R2 = 0.95). Despite the difficulty of identifying shadows, the CED method achieved an overall accuracy of 89.23% with a kappa coefficient of agreement of 0.72, similar to that of the OBIA method at medium segmentation scale (138).

Microstructure and corrosion behaviour of AlCoFeNiTiZr high-entropy alloy films

ABSTRACTThree kinds of AlCoFeNiTiZr high-entropy alloy films with different elements ratios were prepared using magnetron sputtering. The films were composed of fcc solid solution phases and amorphous phases with typical uniform polycrystal microstructure. The anticorrosion performances of the films were tested in a NaCl solution. The changes of microstructures and composition were quantitatively characterised by XPS, SEM and TEM. During the corrosion reaction process there was a decrease in the contents of Al, Ti, Zr and Fe elements. The increase in Fe-Co-Ni content lead to an increase of passivation area, and a subsequent increase in corrosion potential (Ecorr) and a decrease in the corrosion current density (Icorr). A decrease in the crystal lattice distortion, vacancy, dislocation and grain boundary segregation was also noted increasing corrosion resistance. Additionally, both the grain refinement and the total grain boundary length in the film reduced, and as a result the corrosion resistance improved.

Evolution of the Pattern of Spatial Expansion of Urban Land Use in the Poyang Lake Ecological Economic Zone.

To grasp the evolutionary characteristics and regularity of urban land expansion patterns in the Poyang Lake Ecological Economic Zone, this study, based on nighttime lighting data, uses the Landsat series satellite simultaneous data and cluster analysis to correct the Defense Meteorological Satellite Program–Operational Linescan System (DMSP-OLS) nighttime lighting data and then uses the auxiliary data-based comparison method to determine the threshold for extracting the urban built-up area. Based on this threshold, a total of eight typical landscape pattern indicators, including landscape total area, total patches number, patches density, maximum patches index, and agglomeration index, etc., are selected. Next, the landscape spatial pattern analysis method and standard deviation ellipse method are used. The results show the following: (1) In 1992–2013, urbanization in the Poyang Lake Ecological Economic Zone expanded rapidly. The urban built-up area increased by 8.13 times, the number of plaques increased by 1.5 times, and the shape complexity of landscape plaques gradually increased. There is a large correlation between the changes in the total boundary length, and the average boundary density, the average annual growth rate of the two is 21.33% and 17.45%. (2) The two indicators of maximum plaque index and aggregation index show a downward trend year by year. However, there are some fluctuations and irregularities in the evolution of the total landscape area, total plaque number and plaque density. (3) The long axis and the short axis of the standard deviation ellipse of the Poyang Lake Ecological Economic Zone show small variation during the inspection period and generally have an elliptical shape. The movement of the center of gravity is mainly from the southwest to the northeast, but the migration of the center of gravity is relatively small. Based on this, this paper proposes three countermeasures and suggestions as a guide to promote the optimization and development of the spatial expansion pattern of the Poyang Lake eco-economic zone.

Spatial priority conservation areas for vegetation habitat across the Upper Reaches of Min River located in Sichuan Province, China

Considered as a hotspot for biodiversity in the upstream of Yangtze River, many vegetation habitats have been seriously damaged in Upper Reaches of Min River located in Sichuan Province, China due to the continuous deterioration of ecosystems. This work aims to define important protected areas with higher vegetation habitat suitability index. Through integrating the spatial distribution of vegetation habitat suitability (HS) index into systematic conservation planning, this study constructed spatial priority conservation areas of vegetation habitat under different protection targets in the Upper Reaches of Min River, China. In this regard, effective information regarding vegetation HS and its priority conservation planning responded to conservation target level changes and boundary length effect provide useful support for diverse stakeholders in vegetation habitat planning, management and policies. The southeastern places played an important role in the priority conservation areas for vegetation habitat, and there were more conservation areas located in east of study site than west. As increasing of target levels (ranged 10%–90% percentages of summing amount for vegetation HS index at watershed scale), the spatial priority conservation areas for vegetation habitat gradually extended from the south to the north. The spatial structure of priority conservation areas for vegetation habitat with boundary length effect was more compact than that without boundary length effect. The total priority conservation areas with boundary length effect were approximate to those without boundary length effect, but the total boundary length of former was far less than that of latter. It suggested that integrating boundary length effect to systematic conservation planning of vegetation habitat could produce more aggregated conservation patches and increase connectivity among patches. The total priority conservation areas for vegetation habitat were traded off against total boundary length of reserve networks. It indicated that this tradeoff information could help stakeholder to reasonably allocate investment to maintain reserve network under different target levels. The proposed approach could provide useful information to assess the responses of priority conservation areas for vegetation habitat to different protected targets and boundary length effect, and also guarantee ecosystem sustainability across watershed.

Interaction of water with faceted NiO(1 1 1) surface tuned by films thickness

The interaction of water with the polar surface of NiO(1 1 1) films has been investigated using various in situ surface analytical techniques, as well as ex situ scanning electron microscopy and atomic force microscopy. The {1 0 0} facets are formed on NiO(1 1 1) films upon annealing. The boundary between {1 0 0} facet and bare (1 1 1) face and the corner on the facet can facilitate dissociation of water. The total boundary length and the number of corner sites vary with film thickness. The dissociated hydroxyls are thermally stable up to 700 K on the thinner films. Consequently the activity of water dissociation can be tuned by adjusting the film thickness.