Excess Nickel Research Articles

Characterization of T cell receptors in a novel murine model of nickel-induced intraoral metal contact allergy.

Nickel is a component of several alloy types that are widely used in our environment, including several dental alloy types that cause intraoral metal contact allergy. However, metal-specific immune responses in the oral mucosa have not been elucidated because a suitable animal model has not been established. In this study, we established a novel murine model of nickel-induced intraoral metal contact allergy and aimed to elucidate the immune response in terms of T-cell receptor repertoire and cytokine profiles in inflamed oral mucosa. The intraoral metal contact allergy model was induced by two sensitizations of nickel plus lipopolysaccharide solution into the postauricular skin followed by a single nickel challenge of the buccal mucosa. Cytokine expression profiles and T-cell phenotypes were determined by quantitative polymerase chain reaction. T cells accumulated in the cervical lymph nodes and inflamed oral mucosa were characterized by analyzing their T-cell receptor α- and β-chain repertoires, and the nucleotide sequences of complementary determining region 3. Significant swelling and pathological features were histologically evident at 1 day after challenge in mice with nickel allergy. At 1 day after the challenge, CD8-positive T cells producing high levels of T helper 1 type cytokines had accumulated in the allergic oral mucosa. At 7 days after the challenge, excessive nickel allergy in the oral mucosa was suppressed by regulatory T cells. Characterization of the T-cell receptor repertoire in nickel allergic mice revealed the presence of natural killer T cells and T cells bearing Trav6-6-Traj57 at 1 day after the challenge. Our murine model of nickel-induced intraoral metal contact allergy showed that natural killer T cells and T cells bearing Trav6-6-Traj57 might be involved in the immune responses of nickel-induced intraoral metal contact allergy.

Ni tolerance and its distinguished amelioration by chelating agents is reflected in root radius of B. napus cultivars

The negative effect of excess nickel (Ni) on plants is well investigated but there is only little information on its influence on root anatomy and a possible amelioration by chelating agents. In this study, we utilized light microscopy to observe anatomical changes in canola (Brassica napus) roots and investigated the element content by X-ray microanalysis. Ni-tolerant (Con-II) and Ni-sensitive cultivars (Oscar) were selected for this purpose. The plants were treated with 30 ppm NiSO4. Then, citric acid and ethylene-diamine-tetra-acetic acid (EDTA) (alone or in combination) were applied to observe the influence of chelating agents in metal stress amelioration. Ni treatment led to significant swelling of the roots in the Con-II variety as compared to the cultivar Oscar. Application of EDTA reduced the root radius of Con-II plants and this effect for Ni tolerance is discussed. According to X-ray microanalyses, Ni ions were more dispersed in the sensitive cultivar as indicated by metal adsorption to the cell wall. We investigate the hypothesis that an enhanced capacity of binding metals to the cell wall allows the plants to tolerate more heavy metals.

An Upper Limit on Nickel Overabundance in the Supercritical Accretion Disk Wind of SS 433 from X-ray Spectroscopy

We take advantage of a long (with a total exposure time of 120 ks) X-ray observation of the unique Galactic microquasar SS 433, carried out with the XMM-Newton space observatory, to search for a fluorescent line of neutral (or weakly ionized) nickel at the energy 7.5 keV. We consider two models of the formation of fluorescent lines in the spectrum of SS 433: 1) due to reflection of hard X-ray radiation from a putative central source on the optically thick walls of the accretion disk "funnel"; and 2) due to scattering of the radiation coming from the hottest parts of the jets in the optically thin wind of the system. It is shown, that for these cases, the photon flux of Ni I K$_{\alpha}$ fluorescent line is expected to be 0.45 of the flux of Fe I K$_{\alpha}$ fluorescent line at 6.4 keV, for the relative nickel overabundance $Z_{Ni}/Z = 10$, as observed in the jets of SS 433. For the continuum model without the absorption edge of neutral iron, we set a 90 per cent upper limit on the flux of the narrow Ni I K$_{\alpha}$ line at the level of $0.9 \times 10^{-5}$ ph s$^{-1}$ cm$^{-2}$. For the continuum model with the absorption edge, the corresponding upper limit is $2.5 \times 10^{-5}$ ph s$^{-1}$ cm$^{-2}$. At the same time, for the Fe I K$_{\alpha}$ line, we measure the flux of $9.9_{8.4}^{11.2} \times 10^{-5}$ ph s$^{-1}$ cm$^{-2}$. Taken at the face value, the results imply that the relative overabundance of nickel in the wind of the accretion disc should be at least 1.5 times less than the corresponding excess of nickel observed in the jets of SS 433.

Steam reforming of acetic acid over Ni/Al2O3 catalysts: Correlation of nickel loading with properties and catalytic behaviors of the catalysts

In this study, steam reforming of acetic acid over the Ni/γ-Al2O3 catalysts with varied nickel contents (from 2.5 to 40 wt%) was performed, aiming to investigate the effects of nickel loading on properties and catalytic behaviors of the catalysts. The results show that the interaction of nickel species with alumina varies with varied nickel loading. At lower nickel loadings, the nickel strongly interacting with alumina are the main species, while with the saturation of the reactive sites of alumina via loading more nickel, the proportion of the nickel species weakly interacting with alumina increased remarkably. Excess nickel on alumina can fill the pores, decreasing the reduction degree of nickel oxides, the specific area (from ca. 277 to 132 m2 g−1 with the increase of nickel loading to 40 wt%), the pore volume, and the pore diameters. Nickel loading also significantly affects the catalytic activity, stability of the catalyst and the resistivity towards coking. With the increase of nickel loading to 10 wt%, the activity of the catalyst reached a plateau. The further increase of nickel loading did not further increase the activity, but increased the stability and the tolerance towards the deactivation induced by coking. In addition, with higher nickel loadings, the coke formed has more large aromatic ring system.

Use of zeolite to neutralise nickel in a soil environment

Nickel is a heavy metal which is a stable soil pollutant which is difficult to remediate. An attempt to reduce its impact on the environment can be made by changing its solubility. The right level of hydrogen ions and the content of mineral and organic colloids are crucial in this regard. Therefore, methods to neutralise heavy metals in soil are sought. There are no reports in the literature on the possibility of using minerals in the detoxication of a soil environment contaminated with metals. It is important to fill the gap in research on the effect of zeolites on the microbiological, biochemical and physicochemical properties of soils under pressure from heavy metals. Therefore, a pot experiment was conducted on two soils which examined the effect of various levels of contamination of soil with nickel on the activity of soil enzymes, physical and chemical properties and growth and development of plants. An alleviating effect of zeolite Bio.Zeo.S.01 on the negative impact of nickel on the soil and a plant (oats) was examined. The enzyme activity and the oat yield were found to be significantly and negatively affected by an excess of nickel in the soil, regardless of the soil type. The metal was accumulated more in the oat roots than in the above-ground parts. An addition of zeolite decreased the level of accumulation of nickel in oats grown only on sandy-silty loam. Zeolite Bio.Zeo.S.01 used in the study only slightly alleviated the negative effect of nickel on the biochemical properties of soil. Therefore, its usability in the remediation of soil contaminated with nickel is small.

Effect of Cooling Rates on the Transformation Behavior and Mechanical Properties of a Ni-Rich NiTi Alloy

Slightly nickel-rich Ni–Ti alloys (typically 50.5–51% atomic percent nickel) are commonly used to produce devices that are superelastic at body temperature. This excess nickel can be tolerated in the NiTi matrix when its temperature is above the solvus of about 600 °C, but will precipitate out during lower temperatures. Recent work has been done on exploring the effect lower temperatures have on the material properties of NiTi. Findings showed that properties begin to change at temperatures as low as 100 °C. It is because of these results that it was deemed important to better understand what may be happening during the quenching process itself. Through running a combination of DSC and tensile tests on samples cooled at varying rates, it was found that the cooling rate has an effect on properties when heat treated above a specific temperature. Understanding how quickly the alloy must be cooled to fully retain the supersaturated NiTi matrix is important to optimizing processes and anticipating material properties after a heat treatment.

Nitric oxide induces rice tolerance to excessive nickel by regulating nickel uptake, reactive oxygen species detoxification and defense-related gene expression

Soil contamination with nickel (Ni) is a persistent threat to crop production worldwide. The present study examined the putative roles of nitric oxide (NO) in improving Ni-tolerance in rice. Our findings showed that application of exogenous sodium nitroprusside (SNP), a NO donor, significantly improved the growth performance of rice seedlings when grown under excessive Ni. The enhanced Ni-tolerance of rice prompted by SNP could be ascribed to its ability to regulate Ni uptake, decrease Ni-induced oxidative stress as evidenced by reduced levels of hydrogen peroxide, malondialdehyde, and electrolyte leakage in Ni-stressed plants. The positive roles of NO against Ni-toxicity also reflected through its protective effects on photosynthetic pigments, soluble proteins and proline. SNP also boosted antioxidant capacity in Ni-stressed plants by maintaining increased levels of ascorbate, enhanced activities of ROS-detoxifying enzymes, particularly peroxidase (POD) and catalase (CAT) in both roots and shoots compared with Ni-stressed alone plants. Moreover, SNP treatment also upregulated the transcript levels of CAT, POD, ascorbate peroxidase, glutathione reductase and superoxide dismutase genes in shoots under Ni-stress. Using different sulfide compounds and NO scavenger cPTIO, we also provided evidence that NO, rather than other byproducts of SNP, contributed to the improved performance of rice seedlings under Ni-stress. Collectively, our results conclude that exogenous SNP-mediated modulation of endogenous NO enhanced rice tolerance to Ni–stress by restricting Ni accumulation, maintaining photosynthetic performance and reducing oxidative damage through improved antioxidant system, thereby suggesting NO as an effective stress regulator in mitigating Ni-toxicity in economically important rice, and perhaps in other crop plants.

Concentrations of Trace Elements in Hemodialysis Patients: A Prospective Cohort Study

Low concentrations and excessive concentrations of trace elements have been commonly reported in hemodialysis patients, but available studies have several important limitations. Random sample of patients drawn from a prospective cohort. 198 incident hemodialysis patients treated in 3 Canadian centers. We used mass spectrometry to measure plasma concentrations of the 25 elements at baseline, 6 months, 1 year, and 2 years following enrollment in the cohort. We focused on low concentrations of zinc, selenium, and manganese and excessive concentrations of lead, arsenic, and mercury; low and excessive concentrations of the other 19 trace elements were treated as exploratory analyses. Low and excessive concentrations were based on the 5th and 95th percentile plasma concentrations from healthy reference populations. At all 4 occasions, low zinc, selenium, and manganese concentrations were uncommon in study participants (≤5.1%,≤1.8%, and≤0.9% for zinc, selenium, and manganese, respectively) and a substantial proportion of participants had concentrations that exceeded the 95th percentile (≥65.2%,≥74.2%, and≥19.7%, respectively). Almost all participants had plasma lead concentrations above the 95th percentile at all time points. The proportion of participants with plasma arsenic concentrations exceeding the 95th percentile was relatively constant over time (9.1%-9.8%); the proportion with plasma mercury concentrations that exceeded the 95th percentile varied between 15.2% and 29.3%. Low arsenic, platinum, tungsten, and beryllium concentrations were common (>50%), as were excessive cobalt, manganese, zinc, vanadium, cadmium, selenium, barium, antimony, nickel, molybdenum, lead, and chromium concentrations. There was no evidence that low zinc, selenium, or manganese concentrations exist in most contemporary Canadian hemodialysis patients. Some patients have excessive plasma arsenic and mercury concentrations, and excessive lead concentrations were common. These findings require further investigation.

Water and sediment quality in Cartagena Bay, Colombia: Seasonal variability and potential impacts of pollution

Cartagena Bay, one of the Caribbean's hot spots of pollution, is an estuarine system connected to the Caribbean Sea by two straits. Large freshwater discharges from the Dique Canal into the south of the bay produce estuarine conditions strongly related to the seasonal variability of runoff from the Magdalena River watershed. The bay's seasonal conditions may be characterized by three seasons: strong winds/low runoff (Jan.–April), weak winds/intermediate runoff (May–Aug.), and weak winds/high runoff (Sept.–Dec.). This coastal zone is known to be impacted by land-based sources of pollution, including continental runoff, industrial effluents and domestic wastewater. However, previous studies have not sufficiently ascertained the spatio-temporal extent of this pollution. This study addresses the following research question: What is the current extent of water and sediment pollution in Cartagena Bay and which factors control its seasonal variability? Monthly seawater samples (Sept.2014–Aug.2015) were taken from surface and bottom depths at 16 stations in and around Cartagena Bay and analyzed for physical, chemical, and biological parameters. Surface sediments were sampled from the bay's bottom every three months and analyzed for various trace metals. Seasonal variability was observed in nearly all of the water quality parameters, with higher concentrations usually coinciding with the high runoff season. Potential pollution impacts are shown by wet-season averages of total suspended solids (45.0 ± 89.5 mg/l), turbidity (26.1 ± 59.7 NTU), biological oxygen demand (1.20 ± 0.91 mg/l), chlorophyll-a (2.47 ± 2.17 μg/l), nitrate (171.1 ± 112.6 μg/l), phosphate (43.1 ± 63.5 μg/l), total phosphorus (85.3 ± 77.2 μg/l), phenol (2.9 ± 17.4 mg/l), faecal coliforms (798 ± 714 MPN/100 ml) and enterococci (32 ± 30 CFU/100 ml) in excess of recommended threshold values for marine conservation and recreational adequacy. The bay's hypoxic conditions are evident with low dissolved oxygen concentrations (<4 mg/l) found at bottom depths during the wet season, moderate concentrations in the windy season, and low concentrations approaching surface waters during the transitional season, showing a seasonality related to the variability of water circulation and vertical stratification. Lower chlorophyll-a levels found in the water column during the wet season suggest that primary productivity in this eutrophic system is not limited by nutrients, which are abundant due to land-based effluents, but rather by water transparency which is significantly reduced during the wet season due to large sediment loads discharged from the Dique Canal. Sediments from the bay's bottom were found to have concentrations of mercury, cadmium, chromium, copper and nickel in excess of the Threshold Effects Levels (TEL) used as an indicator of potential impacts on marine life.

Seasonal variation of heavy metal analysis of ground water in and around senthurai taluk in ariyalur district – Tamilnadu.

A Total 16 ground water samples were collected in and around sendurai taluk in Ariyalur district during pre-monsoon, monsoon and post-monsoon seasons and analyzed in order to find out pollution impact. The heavy metal analyses Cu, Zn, Ir, Pb and Ni were determined using atomic absorption spectrophotometer and the results were compared with the World Health Organization (WHO 2011) Standard Values. The heavy metal ions are toxic to human health. This study suggests that the preventive measures which are to be adopted to control the contamination of excess Lead and Nickel present in the water.

Improved Performance for Lithium Excess Layered Oxides By Solid-State Surface Coatings

The design of high voltage and high capacity cathode materials for lithium ion batteries are important for the pressing demand of electric vehicles and portable devices. Of the cathode materials, the lithium excess nickel manganese cobalt layered oxides (Li-Rich NMC), where the lithium-to-transition metal ratio is greater than 1, have been looked at as an alternative due to the possibility of utilizing more than 1 Li in the chemical formula unit which would significantly increase the capacity. However, despite much effort from researchers, the extensive commercial application of the lithium excess material is hindered by several deficiencies, namely the low initial coulombic efficiency, poor cycle life, and poor rate performance. These deficiencies have mainly been attributed to the complicated structural evolution and the formation of a cathode solid electrolyte interface (SEI) layer at the higher voltages (>4.5V). As a result of these surface features, many researchers have investigated the role of surface modification on improving the electrochemical properties. An effective strategy has been through chemical treatments and post-annealing steps to induce the formation of a surface spinel structure prior to electrochemical cycling, which has shown to improve the first cycle coulombic efficiency and rate performance. However, the first cycle coulombic efficiency and the associated cycle stability of these surface treated samples still need further improvement. In this work, at Wildcat Discovery Technologies, we investigate several families of surface coatings, prepared by solid- state synthesis techniques, and show that by modifying the surface coating we can greatly enhance the first cycle coulombic efficiency while also maintaining, or in some cases improving, the cycle stability and rate performance of the Li-Rich NMC material. Wildcat has evaluated the performance of hundreds of surface coatings and show that certain families tend to improve all metrics. In addition we show that certain families reduce gas generation during the first cycle as well as subsequent cycles over the pristine the Li-Rich NMC material.

Improving the Quality of the Coating at Hot-Dip Galvanizing of Machine Steels in the Zinc Melt with Microadditives of Nickel

The technology of microalloying zinc melt by nickel is widely used to control the thickness of the zinc coating when the machine steels are subject to hot-dip galvanization. However, in some cases inclusions of Ni-Zn-Fe dross are formed on surface of the products, which leads to their deterioration. The aim of this work is to investigate the microstructure, mechanism of formation and elemental composition of this dross. Conditions for the formation of different phases in the coating were analyzed using Ni-Zn-Fe ternary diagram. It was found that Ni-Zn-Fe dross is a ζ-phase containing about 0.5 at. % nickel and isomorphic with FeZn13-phase. The main reasons for the formation of Ni-Zn-Fe dross are Zn-Fe contamination in the melt, the excess nickel concentration (more than 0.06 at.%), and the irregular nickel concentration in the melt. Methods for preventing this type of defects in hot-dip galvanization have been proposed.

Highly loaded Ni-based catalysts for low temperature ethanol steam reforming.

This paper describes the design of high-loading Ni/Al2O3 catalysts (78 wt% Ni) for low temperature ethanol steam reforming. The catalysts were synthesized via both co-precipitation (COP) and impregnation (IMP) methods. All the catalysts were measured by N2 adsorption-desorption, XRD, H2-TPR, and H2 pulse chemisorption. The characterization results demonstrated that the preparation method and the loading significantly affected the nickel particle size, active nickel surface area and catalytic performance. Over COP catalysts, large nickel particles were presented in nickel aluminum mixed oxides. In comparison, IMP catalysts gained more "free" NiO particles with weak interaction with the aluminum oxide. Consequently, COP catalysts yielded smaller nickel particles and larger active nickel surface areas than those of IMP catalysts. High loading is beneficial for obtaining sufficient active nickel sites when nickel particles are dispersed via COP, whereas excessive nickel content is not desired for catalysts prepared by IMP. Specifically, the 78 wt% nickel loaded catalyst synthesized by COP possessed small nickel particles (∼6.0 nm) and an abundant active nickel area (35.1 m(2) gcat(-1)). Consequently, COP-78 achieved superior stability with 92% ethanol conversion and ∼35% H2 selectivity at 673 K for 30 h despite the presence of a considerable amount of coke.

Evaluation of Toxicity Level of Nickel on Growth, Photosynthetic Efficiency, Antioxidative Enzyme, and Its Accumulation in Cauliflower

A study was conducted to determine the toxicity level of nickel using cauliflower (Brassica oleracea L. var. botrytis) cv. Snowball grown in refined sand with complete nutrient solution for 79 days. At day 80, plants were separated into three lots. One lot was treated as the control (0.0001 mM Ni) while other two lots were supplied with excess nickel (Ni) at 0.1 and 0.5 mM. The toxicity symptoms of Ni appeared as chlorosis of young leaves. No curd was formed at 0.5 mM Ni supply. Excess Ni decreased biomass, chlorophyll, Hill reaction activity, and carbohydrate fraction, and enzyme activities of catalase, peroxidase, and acid phosphatase in leaves. Excess Ni increased concentration of starch, phenol, and nonprotein nitrogen and decreased protein nitrogen in leaves. Increase in Ni supply increased Ni concentration in all parts of cauliflower, whereas the concentration of phosphorus, sulfur, iron, and manganese decreased significantly.

Nickel Allergy and Our Children's Health: A Review of Indexed Cases and a View of Future Prevention.

Nickel is the leading cause of allergic contact dermatitis (ACD) from early childhood through adolescence. Studies have shown that skin piercings and other nickel-laden exposures can trigger the onset of nickel ACD in those who are susceptible. Nickel ACD causes a vast amount of cutaneous disease in children. Cases of nickel ACD in children have been reported in peer-reviewed literature from 28 states. Common items that contain inciting nickel include jewelry, coins, zippers, belts, tools, toys, chair studs, cases for cell phones and tablets, and dental appliances. The diagnosis of nickel ACD has been routinely confirmed by patch testing in children older than 6 months suspected of ACD from nickel. Unlike in Europe, there are no mandatory restrictions legislated for nickel exposure in the United States. Denmark has demonstrated that regulation of the nickel content in metals can lower the risk of ACD and the associated health care-related costs that arise from excess nickel exposure. To further awareness, this article reviews the prominent role of nickel in pediatric skin disease in the United States. It discusses the need for a campaign by caretakers to reduce nickel-related morbidity. Lastly, it promotes the model of European legislation as a successful intervention in the prevention of nickel ACD.

Activation of Autophagy by Metals in Chlamydomonas reinhardtii.

Autophagy is an intracellular self-degradation pathway by which eukaryotic cells recycle their own material in response to specific stress conditions. Exposure to high concentrations of metals causes cell damage, although the effect of metal stress on autophagy has not been explored in photosynthetic organisms. In this study, we investigated the effect of metal excess on autophagy in the model unicellular green alga Chlamydomonas reinhardtii. We show in cells treated with nickel an upregulation of ATG8 that is independent of CRR1, a global regulator of copper signaling in Chlamydomonas. A similar effect on ATG8 was observed with copper and cobalt but not with cadmium or mercury ions. Transcriptome sequencing data revealed an increase in the abundance of the protein degradation machinery, including that responsible for autophagy, and a substantial overlap of that increased abundance with the hydrogen peroxide response in cells treated with nickel ions. Thus, our results indicate that metal stress triggers autophagy in Chlamydomonas and suggest that excess nickel may cause oxidative damage, which in turn activates degradative pathways, including autophagy, to clear impaired components and recover cellular homeostasis.

Activity and Durability of Iridium Nanoparticles in the Oxygen Evolution Reaction

Although electrochemical water splitting currently represents a small amount of the US hydrogen supply, its role is expected to grow with the emergence of a hydrogen-based infrastructure.[1] Electrolysis is reasonably cost-competitive with a variety of technologies, including batteries (solid state and flow), pumped hydro, and compressed air.[2] When coupled with renewable energy sources, such as wind and solar, electrochemical water splitting can produce hydrogen using a nearly carbon free pathway.[3] The commercial progress of electrolyzers is limited in part by the cost of the catalyst layer. The oxygen evolution reaction is the focus of electrocatalyst development due to slow kinetics relative to hydrogen evolution; iridium nanoparticles are commonly used to catalyse oxygen evolution, with platinum added to ensure conductivity throughout the catalyst layer. Extended surface nanostructures have previously been developed as electrocatalysts in hydrogen fuel cells, where they have produced an order of magnitude higher specific activity than nanoparticles in oxygen reduction and demonstrated a potential benefit in accelerated stress tests.[4] Extended nanostructures have recently been developed for the oxygen evolution reaction, where a similar specific activity improvement was observed in rotating disk electrode (RDE) half-cells. Catalysts formed by spontaneous galvanic displacement are ideally situated, being able to take advantage of the specific activities generally associated with the catalyst type, while significantly improving upon the traditionally low surface areas of extended surfaces. This approach has been used in forming iridium-nickel and iridium-cobalt nanowires.[5] While nanoparticles have modest site-specific activity in oxygen reduction and evolution, nanoparticle evolution catalysts are at a particular disadvantage with regards to surface area, since carbon supports cannot be used at high potentials. Iridium-cobalt and iridium-nickel nanowires have been synthesized with surface areas of 70 m2 gIr ‒ 1, more than double the nanoparticles. In RDE half-cells, the extended nanostructures produce an oxygen evolution mass activity 7 to 8 times greater throughout the kinetic region. Accelerated stress tests were completed by potential holds and cycling over a variety of conditions to study catalyst degradation and establish standardized testing protocols. Acid treatment has been used to remove excess nickel and cobalt template, improving catalyst durability. Following accelerated stress tests in RDE half-cells, iridium-cobalt and iridium-nickel nanowires exceed the mass activity of nanoparticles by more than an order of magnitude. Membrane electrode assembly (MEA) fabrication of these materials has produced electrolyzers with higher performance than the benchmark device. Recent improvements in MEA performance suggest that the promise of extended surface catalysts observed in half-cells can be realized in the application. [1] R. Forgie, G. Bugosh, K.C. Neyerlin, Z. Liu, P. Strasser, Electrochemical and Solid-State Letters, 13 (2010) B36-B39. [2] K. Harrison, M. Peters, in: U.S. Department of Energy (Ed.), http://www.hydrogen.energy.gov/pdfs/review13/pd031_harrison_2013_o.pdf, 2013. [3] K. Harrison, M. Peters, C. Ainscough, in: U.S. Department of Energy (Ed.), http://www.hydrogen.energy.gov/pdfs/progress13/ii_a_2_harrison_2013.pdf, 2013. [4] S.M. Alia, Y.S. Yan, B.S. Pivovar, Catalysis Science & Technology, 4 (2014) 3589-3600. [5] H. Xu, High-Performance, Long-Lifetime Catalysts for Proton Exchange Membrane Electrolysis, in: U.S. Department of Energy (Ed.), http://www.hydrogen.energy.gov/pdfs/review14/pd103_xu_2014_o.pdf, 2014. Figure 1. Surface areas (x-axis) and site-specific oxygen evolution activities (y-axis) of iridium-cobalt nanowires, iridium-nickel nanoparticles, and iridium nanoparticles prior to (red, blue, black) and following (dark red, dark blue, grey) durability testing in RDE half cells. Arbitrary mass activities (1, 4, 7 A mgIr ‒ 1) are included as solid black lines. Figure 1

Ni(II)20 "Bowls" from the Use of Tridentate Schiff Bases.

The reactions of N-salicylidene-o-aminophenol or its derivatives and excess of nickel(II) acetate in alcohols have led to Ni(II)20 clusters with an unprecedented "bowl" metal topology.

화순항내 준설토사의 양빈재 유효활용을 위한 적합성 평가

Dredged materials for effective use in Hwasun-port pollution analysis, Ni(nickel) in excess of the standard showed that the whole point. However, according to the revised standards effective utilization exceeds the reference value, even if no anthropogenic sources Pearl ratio less than 10% of the average weight of the ecotoxicological tests have passed, and if so it can be used to beach nourishment. Therefore, the average weight ratio of pearl and ecotoxicological tests were conducted by marine environment official test method. Mud to 5.37% of the average weight ratio lower than the reference value of 10% that was investigated. Ecotoxicity test using bioluminescent bacteria relative luminescence inhibition in the 0 to 9.13% with no toxicity was determined using benthic amphipods in the control and the test sample relative to the average survival rate is 0% with no toxicity was determined. Therefore, the revised effective use meets all the criteria that can be used to beach nourishment, so that the suitability was assessed.

Effect of Excess nickel On the Growth and Germination of Echium Amoenum (Fisch &amp; CA Mey)

Increasing environmental pollutant, especially heavy metals, is due to the industrialization of human societies. Nickel as one of the essential micronutrients in plants is necessary for normal plant growth and development but in high concentrations- As a heavy metal- exhibits toxicity. In this study the effect of different concentrations of Ni (0, 100, 300µM) was studied on germination, growth and some biochemical parameters of echium amouneum under controlled conditions. Based on these results, Ni had no significant effect on germination. In general, there was a decrease in growth parameters such as fresh and dry weights of aerial parts and roots, relative growth rate (RGR).DOI: http://dx.doi.org/10.3126/ijls.v9i2.12060 International Journal of Life Sciences 9 (2) : 2015; 33-38