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Triple oxygen isotope (Δ′17O) analysis of CO 2 or carbonate is increasingly applied in diverse fields in earth and environmental sciences. One of the widely-used analytical methods for Δ′17O of CO 2 is through Pt-catalyzed oxygen isotope exchange between CO 2 and O 2. However, large inter-laboratory inconsistencies in oxygen isotope fractionation between the two gases have been reported, potentially hindering data comparison across different laboratories. By examining the oxygen isotope fractionations in thermal diffusion experiments for pure O 2 and CO 2 gases as well as CO 2 -O 2 mixtures, we demonstrate that thermal-gradient-induced (TG-induced) isotope fractionation is the main reason for the inconsistencies. The degree of TG-induced oxygen isotope fractionation is affected by temperature contrasts and volume ratios between the hot and cold parts of the extraction line as well as gas composition. Larger thermal contrasts generated larger oxygen isotope fractionations. CO 2 fractionated less than O 2 in the same thermal gradient conditions. For CO 2 -O 2 mixtures, TG-induced oxygen isotope fractionation of O 2 was reduced while that of CO 2 was enhanced, compared with the pure gases. Based on the results of thermal diffusion experiments, we found that the anomalous mass fractionation exponents (0.2 ∼ 0.9) observed in the Pt-catalyzed CO 2 -O 2 isotope exchange experiments can be rationalized quantitatively by a combination of isotopic exchange equilibrium and TG-induced oxygen isotope fractionation. Our model suggests that by weakening TG-induced oxygen isotope fractionation and by increasing the volume fraction of hot zone of a reactor, we can achieve a high precision (<10 per meg) for Δ′17O CO2 through CO 2 -O 2 exchange. Considering the widely existing thermal-gradient conditions in nature, the findings in this study may shed light on the origin of non-mass-dependent isotope fractionation. [ABSTRACT FROM AUTHOR]

• A high linearity and sensitivity CO 2 gas sensor is proposed and demonstrated by using a micro-tapered long-period fiber grating (MT-LPFG). • The sensor exhibits a high linear sensitivity of 0.068 nm/% and an impressively low CO 2 detection limit of 1.2 %, with a linearity of 0.994 as CO 2 levels change. • The superior sensitivity sensor with simple fabrication, stable performance, and non-degenerate performance are significant for fiber sensing design. Accurate detection of carbon dioxide (CO 2) is of great significance to environmental protection. In this study, a simple, highly sensitive, and linearity CO 2 sensors is successfully proposed. Furthermore, for the first time, the sensor was demonstrated by electrospinning a layer of polyether sulfone (PES) nanofiber film wrapped onto a micro-tapered long period fiber grating (MT-LPFG). Given that CO 2 molecules effortlessly permeate the mesh pores of the electrospun PES films, modulations in both the refractive index (RI) and volume of PES films can be induced, consequently leading to alterations in the resonant wavelength of the grating. The experimental results demonstrate the exceptional performance of the MT-LPFG sensor utilizing PES films, showcasing a significant response within a range of (1.99 %-10 %). This sensor exhibits a sensitivity of 0.068 nm/%, linearity of 0.994, and an impressively low CO 2 detection limit of 1.2 %. Moreover, the sensor exhibits exceptional recovery properties and demonstrates clear differentiation between nitrogen (N 2) and CO 2. This cost-effective sensor holds significant economic value and holds promise for widespread application in industrial processes and commercialization. [ABSTRACT FROM AUTHOR]

• Cu-CoOx/AC N were optimized for synergetic-catalysis removal of CO and Hg0 at low-temperature (<200 °C). • CoO ⇌ Co 3 O 4 and Cu 2 O ⇌ CuO were benefit for CO oxidation by Co– and Hg0 removal by Cu-species. • Hg0 removal followed the combination processes of adsorption and catalytic oxidation via L-H mechanism. • Catalysis-oxidation of CO to CO 2 abided by the Mars–van Krevelen mechanism with lattice oxygen species. Cu-Co multiple-oxides modified on HNO 3 -pretreated activated coke (AC N) were optimized for the simultaneous removal of gaseous CO and elemental mercury (Hg0) at low temperature (< 200 °C). It was found that 2%CuOx-10%CoOx/AC N catalyst calcined at 400°C resulted in the coexistence of complex oxides including CuO, Cu 2 O, Co 3 O 4 , Co 2 O 3 and CoO phases, which might be good for the simultaneous catalytic oxidation of CO by Co-species and removal of Hg0 by Cu-species, benefiting from the synergistic catalysis during the electro-interaction between Co and Cu cations (CoO ⇌ Co 3 O 4 and Cu 2 O ⇌ CuO). The catalysis removal of CO oxidation was obviously depended on the reaction temperature obtaining 94.7% at 200 °C, while no obvious promoting effect on the Hg0 removal (68.3%-78.7%). These materials were very substitute for the removal of CO and Hg° from the flue gas with the conditions of 8–20 vol.% O 2 and flue-gas temperature below 200 °C. The removal of Hg° followed the combination processes of adsorption and catalytic oxidation reaction via Langmuir-Hinshelwood mechanism, while the catalysis of CO abided by the Mars-van Krevelen mechanism with lattice oxygen species. Image, graphical abstract Synergetic-catalysis mechanisms for the oxidation of gaseous CO and Hg0 were proposed over Cu-CoOx/AC N catalyst, in which the removal of Hg° followed the combination processes of adsorption and catalytic oxidation reaction via Langmuir–Hinshelwood mechanism, while the catalysis of CO-to-CO 2 abided by the Mars–van Krevelen mechanism with lattice oxygen species. [ABSTRACT FROM AUTHOR]

• Novel light use efficiency model incorporates the coupled impacts of atmospheric-CO 2 fertilization and soil nitrogen limitation. • Without CO 2 fertilization and soil nitrogen effects, the global plant GPP had a lower trend by 32.5% for 2001–2019. • Soil nitrogen stress attenuates the positive effect of CO 2 fertilization on global GPP trend with a large latitudinal difference. • The tropics had a weaker CO 2 fertilization effect than the extratropics. This study is the first to evaluate latitudinal characteristics of the coupled impacts of atmospheric-CO 2 fertilization and soil nitrogen limitation on global plant photosynthesis for 2001–2019 by using a remote sensing-based light use efficiency model (DTEC M- l -CN). It predicted that the global GPP should have increased by 0.40 Pg C a −2 (P MK < 0.001) from 2001 to 2019. Leaf area index change contributed 55.0% to this predicted increase in the global GPP trend, followed by coupled CO 2 and soil nitrogen effects (32.5%) and the effects from the climate forcing (12.5%). Without CO 2 fertilization effects, the global GPP trend was predicted lower by 32.5%. With CO 2 fertilization effects included but without a nitrogen constraint, the model would predict global GPP trend higher by 67.5%. These contrasting changes strongly imply the need to consider all these effects simultaneously to estimate future GPP. Comparing the annual mean CO 2 fertilization factor with and without soil nitrogen stress showed that the fertilization factor under soil nitrogen stress was only 62.5% of that with no soil nitrogen stress. As a result of soil nitrogen stress, annual mean CO 2 response metric (R CO2), indicating the CO 2 fertilization effect, declined from 2002 to 2019. Soil nitrogen stress was found to attenuate the positive effect of CO 2 fertilization on GPP trend with a large latitudinal difference, i.e., the tropics had a weaker CO 2 fertilization effect than the extratropics. This study highlights that soil nitrogen has progressively become limiting on plant response to CO 2 fertilization with a large latitudinal divergence. [ABSTRACT FROM AUTHOR]

[Display omitted] • The coupling reaction of glycerol and CO 2 was successfully realized via heterogeneous catalyst. • Cubic MgO displays more low-coordinated O2– originated from the unique atomic arrangement of (1 1 1) facet. • More low-coordinated O2– leads to abundant strongly basic sites and surface oxygen vacancies. • The reaction mechanism of MgO-C on the coupling reaction was clarified. Developing efficient halogen-free catalysts is still a significant challenge for adsorption and activation of CO 2 and further preparing glycerol carbonate. Herein, we successfully developed heterogeneous MgO catalyst via morphology-oriented regulation to catalyze the coupling reaction of glycerol and CO 2. Specifically, cubic MgO displays more low-coordinated O2– originated from the unique atomic arrangement of (1 1 1) facet, resulting in abundant strong basic sites and surface oxygen vacancies. These strong basic sites promote the adsorption of CO 2 to form thermodynamically stable monodentate carbonates near the oxygen vacancies. In addition, nearby surface oxygen vacancies could further enhance the transfer of electrons into the anti-bonding orbitals of CO 2 molecules. The synergistic catalytic effect between the strong basic sites and the surface oxygen vacancies significantly facilitates the cycloaddition reaction (the most critical step in the coupling reaction). Therefore, under the optimal reaction conditions (140 °C, 2 MPa CO 2 , and 4 h), the MgO-C catalyst showed 83 % glycerol conversion and 44 % glycerol carbonate selectivity. [ABSTRACT FROM AUTHOR]

The reduction reaction of carbon dioxide (RR -CO 2) to CH 3 OH using metal catalysts can reduce the energy required by this process. In this study, we investigated the RR -CO 2 mechanisms with Cu-, Ni-, and Mn-doped carbon nanotubes (CNTs). The substitutional (doping with carbon atom) positions in CNTs are suitable sites for adsorbing Cu, Ni, and Mn metals. The reaction paths to the RR -CO 2 were investigated in the gas and solvent phases. The results demonstrated that the overpotential values with Cu-, Ni-, and Mn-doped CNT(8, 0) and CNT(6, 6) catalysts in the gas and solvent phases were lower than that obtained with metal catalysts in previous studies (−1.116 V). Thus, metal-doped CNT(8, 0) and CNT(6, 6) catalysts with low overpotentials could be applied in the RR -CO 2. • Potential of nano-structures to RR- CO 2 is examined. • Possible reaction mechanisms for CO 2 reduction to CH 3 OH are investigated. • Over potential of RR- CO 2 on nano-structures are lower than metal catalysts. • Nano-structures are proposed as efficient catalysts for RR- CO 2. [ABSTRACT FROM AUTHOR]

This paper discusses the effects of dense carbon dioxide (CO2) on the nickel film obtained in an agitated ternary system of dense CO2 and an electroplating solution with a non-ionic surfactant. On the basis of the transport properties of dense CO2 and hexane discussed within, it was found that both the low viscosity of dense CO2 and its good miscibility with hydrogen play an important role for achieving the higher uniformity and a smoother surface formation of nickel film. [Copyright &y& Elsevier]

• The life cycle of the SC-CO 2 fracturing was subdivided into two stages. • The influence of GSD, K, FFIR, and FFT on crack propagation was studied. • The crack propagation morphology was characterized separately for each stage. • The ratios of the length and width of cracks induced in each stage to the total values were obtained. The use of supercritical carbon dioxide (SC-CO 2) for the fracturing of coal bodies has excellent development prospects and practicability. It alters the fissure structure of coal bodies and achieves CO 2 geological sequestration. This process, which involves the mutual interaction of coal, fissures, supercritical fluid, and gas, can be subdivided into fluid-induced and phase change-induced fracturing stages. Numerical simulation of the SC-CO 2 fracturing was carried out in a stagewise manner to characterize each stage's fracturing performance quantitatively. The effects exerted on the crack propagation behavior by such factors as the ground stress deviation, the permeability coefficient of coal bodies, fracturing fluid injection rate and temperature, was studied in detail for each stage. The crack morphology, length, and width of cracks induced in each stage in proportion to the total crack length and width values were determined and analyzed. The research results show that the crack length ratio of the SC-CO 2 fluid-induced fracturing stage to the total crack length was 80–90%, with the remaining 10–20% corresponding to the CO 2 phase change-induced fracturing stage. This indicates that cracks propagation primarily occurred at the former stage. Meanwhile, the crack width ratios were nearly the same: 40–55% for the former stage versus 45–60% for the latter stage. Thus, the crack width increased dramatically at both stages of the SC-CO 2 fracturing in the coal bodies. The research findings refined the insight into the SC-CO 2 fracturing mechanism in coal bodies. [ABSTRACT FROM AUTHOR]

• The tri-axial SC-CO 2 fracturing test system was used to study the SC-CO 2 fracturing of coal body. • Initiation pressure and period of SC-CO 2 fracturing were obtained. • The surface crack patterns in the SC-CO 2 -FCB were analyzed. • The formation mechanism of complex cracks in SC-CO 2 -FCB was revealed. Supercritical carbon dioxide (SC-CO 2) fracturing, as an environmentally-friendly waterless fracturing mining technology, has attracted more and more attention during the safe mining of coal resources. The propagation pattern of fracturing cracks, including the type, number, length, and direction of crack propagation, is the key basis for the design of coal seam fracturing. The direct observation of the crack propagation pattern in fracturing coal body at the engineering site is quite problematic, so laboratory tests are used to study the coal body fracturing process. Based on the tri-axial SC-CO 2 fracturing test system, the crack propagation pattern in the SC-CO 2 -fractured coal body (SC-CO 2 -FCB) was studied under thermo-hydro-mechanical coupling conditions. SC-CO 2 -FCB sample tests were conducted at different crustal stresses, fracturing fluid injection rates, and fracturing fluid temperatures. The injection pressure evolution was analyzed; the type, number, length, and propagation directions of the sample surface cracks were determined, and the crack distribution in SC-CO 2 -FCB was obtained under the effects of temperature field-seepage field-stress field coupling. From three aspects of fracturing media, fractured substances, and their interactions, the formation mechanism of complex cracks in SC-CO 2 -FCB was revealed, which provided theoretical guidance for applying and promoting SC-CO 2 fracturing in coal mines. [ABSTRACT FROM AUTHOR]

G max : The highest reaction potential energy in the reaction path. [Display omitted] • Influence of Pt on the electronic properties of α-MoC-111 surface. • Inhibition effect of Pt on carbon deposition in WGS reaction. • Preventing surface oxidation by introducing Pt in α-MoC during WGS reaction. • Role of Pt in facilitating water dissociation. Pt/α-MoC is an outstanding catalyst for the low-temperature water gas shift (WGS, CO + H 2 O → H 2 + CO 2) reaction, exhibiting elevated activity, stability, and selectivity. In this study, three significant active site models (α-MoC-111, Pt-111, and Pt 1 /α-MoC-111) in Pt/α-MoC catalyst were established to investigate the promotion effect of Pt on the WGS reaction catalyzed by Pt/α-MoC. The results indicate that a synergistic effect at the metal-carbide interface enhances chemical activity compared to pure Pt-111 and α-MoC-111. Firstly, the surface of Pt 1 /α-MoC-111 exhibits strong metal-support interaction between Pt single atom and α-MoC-111 surface. Compared to the α-MoC-111 surface, the introduction of Pt strengthens the Mo−Mo bond while weakening the Mo−C bond. Secondly, adding a Pt atom significantly increases adsorption strength for CO and H 2 O, while decreasing it for products (CO 2), oxides (O atom), and by-products (C atom). The advantage of suppressing surface carbon deposition and oxidation is observed on the surface of Pt 1 /α-MoC-111. Furthermore, elementary reactions from the three mainstream reaction pathways of the WGS reaction are systematically calculated to evaluate catalytic performance among these three active sites. On the Pt 1 /α-MoC-111 surface, activation energy barriers for H 2 O dissociation and CO oxidation are reduced. This provides theoretical ideas for designing high-efficiency α-MoC based catalysts in the future. [ABSTRACT FROM AUTHOR]

This study proposed a super thermal integrated process for CO 2 capture by using internal thermal integration to reduce the total energy efficiency loss of the power plant. [Display omitted] • Super thermal integrated adsorption carbon capture process (STILT) is proposed. • The detailed modeling steps for the novel STILT process are carried out. • The compared analysis of energy efficiency and capture costs are calculated. • The novel process shows superior techno-economic-environment performance. The heat-integrated solid adsorbent process exhibits the potential to become an energy-saving method for CO 2 capture. Here, a super thermal integrated process (STILT) for CO 2 capture is proposed based on our experimental data. The novel process strengthened the process of internal thermal integration and significantly improved the total energy efficiency. This study further takes the commercial MEA process as the benchmark for the multi-dimensional assessment (considering the techno-economic-environment). When CO 2 products are compressed to 110 bar, the energy efficiency of the STILT process and MEA process is 53.45 % and 48.8 %, and the energy consumption is 1.5 MJ/kgCO 2 and 3.41 MJ/kgCO 2. Without CO 2 compression, the energy efficiencies of the STILT process and MEA process are 55.3% and 50.61%. The energy consumptions are 0.82 MJ/kgCO 2 and 2.63 MJ/kgCO 2. Due to the combination of internal thermal integration and enhanced CO 2 circulation capacity, the capture costs of the STILT process are 25.8–34.94 €·t−1 CO 2 , which significantly outweigh the MEA process (43.3–55.07 €·t−1 CO 2). This exhibits the superior techno-economic-environment advantages of the STILT process. This study harbors tremendous referential significance for the design and scale-up of the industrial CO 2 capture process. [ABSTRACT FROM AUTHOR]

Ni 10 La x /MAO catalysts with high Ni dispersion was prepared by wet impregnation method. Characterization results showed that metal dispersion of Ni obviously improved on catalyst surface after La doping. Under the long-term reaction conditions (800 °C, 10 h), Ni 10 La 5 /MAO catalyst could exhibit the highest catalytic performance (93% of CH 4 conversion, 71% of CO 2 conversion and less than 3% activity loss) with lower Ni particle size (12.6 nm) and carbon deposition (8.9 %). [Display omitted] • La doping significantly increased the content of active species Ni0. • High dispersion of Ni species efficiently inhibited the growth of carbon. • Ni 10 La 5 /MgAl 2 O 4 catalyst owned the highest catalytic activity and stability in methane bi-reforming system. Ni-based catalysts were widely studied for methane reforming system in the past decades, while catalytic deactivation by carbon deposition and metal sintering limited its industrial application life. In this work, La-promoted Ni/MgAl 2 O 4 catalysts were investigated over methane bi-reforming reaction, and significantly improved the activity and stability of catalysts. Multiple characterizations showed that the introduction of La increased the content and dispersion of active species (Ni0), providing sufficient sites for methane adsorption and dissociation. Besides, smaller particle size of active metal (12.6 nm) was proved to inhibiting carbon accumulation on catalyst surface. Ni 10 La 5 /MgAl 2 O 4 catalyst was found to exhibit the highest catalytic performance (93% of CH 4 conversion, 71% of CO 2 conversion and less than 3% activity loss) under long-term reaction conditions (800 °C, 10 h). This work will provide important guiding significance for the design of high-efficiency methane reforming catalysts. [ABSTRACT FROM AUTHOR]

We successfully realized the highly selective aromatization of n-hexane by the assistance of CO 2 over Zn modified HZSM-5 catalyst. The in situ H originated from the C-H activation of n-hexane and cyclohexane could be timely removed through the dynamic evolution between CO 2 and Lewis acid site, thus inhibiting the hydrogen transfer side reaction and promoting the desorption of BTEX. Therefore, the Zn/ZSM-5-CO 2 catalyst exhibits as high as 49.7% BTEX yield, which is nearly 10% higher than that of the Zn/ZSM-5-N 2 catalyst (40.3%). [Display omitted] • The introduction of CO 2 could timely remove the in situ H. • Hydrogen transfer between olefins and aromatics is effectively inhibited. • The binding of hydrogen proton to π electrons is weakened. • The loss of medium strength Lewis acid is significantly reduced. • The Zn/ZSM-5-CO 2 catalyst exhibits as high as 49.7% BTEX yield and superior catalytic stability. Controlling the evolution of H species in CO 2 -assisted alkane activation represents an opportunity for simultaneously upgrading light alkanes and greenhouse gas CO 2. Herein, we successfully realized the highly selective aromatization of n -hexane by the assistance of CO 2 over Zn modified HZSM-5 catalyst. Multi-characterizations demonstrated that the introduction of CO 2 could timely remove the in situ H originated from the C-H activation of n -hexane and cyclohexane through the dynamic evolution of the pentagonal coordination Zn-OH+-(CO)-O-Zn structure. On this basis, hydrogen transfer between olefins and aromatics is effectively inhibited, and the binding between π electrons of benzene ring and hydrogen proton is weakened, accelerating the generation and desorption of BTEX. Therefore, the Zn/ZSM-5-CO 2 displays a record high 49.7% BTEX yield, which is nearly 10% higher than that of the Zn/ZSM-5-N 2 (40.3%). In addition, the loss of medium strength Lewis acid caused by in situ H reduction of Si(Al)-O-Zn structure is significantly reduced, ensuring its superior catalytic stability under long-term conditions. These results may provide some insights for the profitable utilization of petrochemical resources to aromatics over zeolites. [ABSTRACT FROM AUTHOR]

We investigated an electroplating reaction in a series of emulsions between an electroplating solution and dense carbon dioxide (CO2) using a novel fluorinated surfactant F(CF(CF3)CF2O)3CF(CF3)COO(CH2CH2O)7CH3. The electroplating reaction took place in the emulsions as a function of the CO2 volume fraction, and electroplating was found to be possible in an emulsion composed of even 80 vol.% CO2 and 20 vol.% electroplating solution. Films composed of a nanograin structure with a grain size of about 10 nm were obtained. We elucidated the plating reaction by measuring the current values in the emulsion using minute terminals connected to a programmable power supply, while simultaneously observing the dispersion state of the emulsion through a high-pressure view cell. The flow of current values in the emulsion system fluctuated, and the current value decreased together with the amplitude of the fluctuant current when the pressure was increased. The fluctuant current flow in the emulsion was concluded to play an important role in the fabrication of the nanograin nickel structure in the plated film. [Copyright &y& Elsevier]

δ13C and D14C measurements on dissolved inorganic carbon (DIC), particulate organic carbon (POC) and aquatic plants from a karst spring and two spring-fed ponds in Laqiao, Maolan Township, Libo County, southeastern Guizhou of China in January, July and October of 2013 have been carried out to understand the roles of aquatic photosynthesis through DIC uptake in surface karst waters. The mean D14C and δ13C values of DIC for the spring, midstream pond (MP) and downstream pond (DP) are −26 ± 36‰ and −13 ± 2‰, 6 ± 56‰ and −12 ± 3‰, and 0 ± 64‰ and −9 ± 2‰, respectively. The carbon source for the DIC is mainly from biogenic CO 2 rather than the dissolution of limestone rock as the D14C and δ13C of limestone are about −1000‰ and 2‰, respectively. The enrichment trend of D14C DIC and δ13C DIC from the spring to the DP indicates CO 2 exchange between atmospheric CO 2 and DIC, because D14C and δ13C values of atmospheric CO 2 are ca. 50‰ and −8‰, respectively. The average D14C POC values in the spring, MP and DP were −325‰, −123‰ and −158‰, respectively, which are all lower than these of the DIC in each reservoir. The lower D14C values of the POC may be caused by older soil carbon from surface runoff and dust fall. More aquatic algae were formed through photosynthesis in the stream ponds, especially in summer, shown by strongly increased D14C POC and evidence of growth in EDS/SEM analyses. Furthermore, the D14C values of the submerged aquatic plants range from −153‰ to −26‰, reflecting that the aquatic plants used DIC for photosynthesis. The D14C value of an emergent plant which uses atmospheric CO 2 during photosynthesis is 52.5 ± 0.3‰, equivalent to the atmospheric D14C. Seasonal variations of D14C DIC and δ13C DIC are influenced by soil CO 2 input, primary productivity in the ponds, and CO 2 exchange; hydrochemical condition show lower D14C values but higher δ13C values in cold/dry season, and vice versa in summer rainy season. A simple mass balance calculation indicates ~90% of carbon for the spring DIC is from biogenic CO 2 , with higher contribution in summer due to higher productivity. Although this simple calculation may overestimate the biogenic CO 2 , it indicates that organic decomposition is a major carbon source for DIC in the karst hydrological system. The results of the present study have implications for 14C dating on aquatic plant remains, regional and perhaps global carbon budgets, and the different behaviors of 13C and 14C in karst systems. • The DIC carbon source of the karst spring is mainly from biogenic CO2. • 13C and 14C tracing C source and transformation including photosynthesis CO 2 uptake • Aquatic plants uptake DIC CO 2 may cause an older 14C age. • Biological pump effect in terrestrial water can be an important natural carbon sink. [ABSTRACT FROM AUTHOR]

A nanocrystalline nickel film was prepared by an electroplating method in a constantly agitated ternary system of dense carbon dioxide (CO2) and electroplating solution using a surfactant. The averaged grain size of the plated Ni film was 11.1 nm. In contrast, a nickel film prepared from an electroplating solution by a conventional method without the use of surfactant had an average grain size of about 19.8 nm. The Vickers hardness of the film obtained by the new method was about 680 Hv, while that prepared from the electroplating solution alone was only about 550 Hv. As a consequence, it can be deduced that grain-size strengthening was observed in the electroplated film obtained using this emulsion system. [Copyright &y& Elsevier]

High quality nickel films having fine grains have been developed using a new electroplating method involving the emulsion of a supercritical carbon dioxide, an electroplating solution and a surfactant. The plated films using this method have a uniformity of the surface and Vickers hardness, which is better than the results obtained by using conventional electroplating methods. [Copyright &y& Elsevier]