Nickel Target Research Articles

In-flight antiproton annihilation on nuclei at low energies

The results of the annihilation cross sections measurement of 5.3 MeV antiprotons on nickel, tin, platinum and Mylar targets performed by the ASACUSA Collaboration at CERN are presented and compared with the existing data and models. From the experimental point of view the presented data are the first measurement of antinucleon annihilation cross sections at low energies obtained with a pulsed beam. This results open the road for the next measurements at the very low energies of the order of 100 keV that are in progress by the ASACUSA Collaboration. The experimental method foreseen for the 100 keV measurement is illustrated.

Synthesis of Carbon Encapsulated Nickel Nanoparticles by Laser Ablation in Liquid

Carbon encapsulated nickel nanoparticles (CENNPs) with high purity were fabricated by laser ablation of nickel target in ethanol. The size of CENNPs varies from tens to hundreds of nanometers, and CENNPs show two kinds of typical morphologies i. e. a nickel core with a carbon shell or a nickel core with two carbon shells. Transmission electron microscopy indicated that the CENNPs formed as a result of laser evaporation of the nickel target and the decomposition of ethanol, whose carbon atoms mixed with the nickel vapor, and Ni/C liquid droplets appeared during the cooling stage. The carbon shells formed by precipitation of carbon atoms on the surface of the nickel cores led to the formation of CENNPs.

The influence of Ni content on the characteristics of C–Ni thin films

C–Ni thin films have been obtained by dual sputtering of graphite and nickel targets. This configuration allows the synthesis of coatings with high carbon content and an accurate control of the composition and degree of dispersion of metallic particles within the coatings. The Ni/(Ni+C) ratio within the films, as determined by XPS (X-ray photoelectron spectroscopy) analysis, varied between 5.8% and 62%. The films were investigated by using Grazing Angle X-ray Diffraction (GXRD), Raman spectroscopy and Scanning Electron Microscopy (SEM).An evolution of the coatings morphology from a poor defined columnar structure to a well defined one with the increasing relative Ni content has been noticed. Depending on the chemical composition of the films, a large distribution of the electrical resistivity values of the films has been observed. The variation of the coating resistivity is related to a change from a structure consisting of metallic particles embedded in an amorphous carbon matrix to a metallic crystalline structure.

Structure of thin-film nickel-carbon composites formed by microwave plasma-enhanced chemical vapor deposition

The results of structure research of thin-film nickel-carbon hydrogenated composites formed by the method of the combination of plasma-enhanced chemical vapor deposition of carbon from mixture of reactive gases (Ar + CH4) and physical sputtering of the nickel target are presented. It has been established in the study of composites by transmission electron microscopy that the microstructure of thin-film composites changed from fragmenting columnar to finely dispersed with increase in carbon concentration.

Preparation of self-supporting nickel targets from 58Ni, 60Ni and 61Ni

The investigation of the distribution of the fusion-barrier height by heavy-ion collisions requires thin self-supporting targets. To increase the accuracy of the measurement the thickness and homogeneity has to be known as precisely as possible.We prepared the self-supporting nickel foils out of the isotopes 58Ni, 60Ni and 61Ni. The resulting targets were between 75 and 105μg/cm² thick. The foils were produced on copper backing by electron-beam gun evaporation and by extracted ion-beam sputtering, both in high vacuum. To obtain self-supporting nickel foils the copper was removed by etching. We will discuss and compare both methods.

Highly conductive nanoclustered carbon:nickel films grown by pulsed laser deposition

An enhancement by 5 orders of magnitude of the electrical conductivity of nanoclustered carbon films is reported by incorporation of metallic atoms, but without significant morphological changes. Films were deposited by 248 nm pulsed laser ablation of both a pyrolytic graphite target and a mixed carbon–nickel (C:Ni) target, and structural analysis revealed that similar film morphologies were obtained when deposition was carried out using either target. Compositional analysis demonstrated a preferential incorporation of nickel over carbon in the resulting films (cf. the composition of the target). This non-stoichiometric transfer was also observed for films grown by 193 nm laser ablation of the C:Ni target, for which the enhancement was more pronounced, indicating that the ablation mechanism and the subsequent transfer are important in determining the eventual film composition.

Structure and magnetic state of the films deposited by laser ablation of composite nickel and palladium targets

Transmission electron microscopy, electron diffraction, and vibrating-sample magnetometry are used to show that a metastable hcp structure can form in both nickel and Ni-Pd alloy films during alternating sputtering of the Ni and Pd components of composite targets. The hcp lattice parameters increase monotonically when the palladium content in a sputtered target increases in the range 0–75%. The ratio of the hcp lattice parameters c/a is close to the ideal ratio for the hcp lattice (1.63) within the limits of experimental error. In the as-deposited state, nickel and Ni-Pd alloy films with an hcp structure have no magnetic moment. Upon annealing, the films transform into a ferromagnetic state with an fcc structure. The concentration dependence of the lattice parameter of the fcc solid solution a 0 is found to exhibit a positive deviation from Vegard’s law, which is characteristic of alloys with a concave liquidus line.

Study of the K shell photoelectric parameters of Dy, Yb and W atoms using low energy bremsstrahlung radiation

Low energy external bremsstrahlung (EB) photons were used to estimate the K shell photoelectric parameters; the K shell photoelectric cross section at the K edge, the K shell binding energy, the K shell jump ratio, the K shell jump factors, the Davisson-Kirchner ratio and the K shell oscillator strength for dysprosium (Dy), ytterbium (Yb) and tungsten (W) atoms. The EB photons are produced in the nickel (Ni) target by using the beta particles from a weak beta source of 90Sr–90Y. These photons are made to fall on these elemental targets of our interest and the transmitted spectrum is measured using GMX 10P HPGe detector coupled to an 8K multichannel analyzer. The sharp decrease at the K edge in the measured spectrum is used to determine the K shell photoelectric parameters of these elements. The experimental results are in good agreement with the theoretical values.

One step purification process for no-carrier-added 64Cu produced using enriched nickel target

Abstract Copper-64 has found many applications in positron emission tomography (PET). Its half-life allows to use it for dosimetric studies associated to copper-67 targeted radiotherapy in cancer treatment. The use of 64Ni(p,n)64Cu nuclear reaction is known to produce 64Cu in large amount and with a high specific activity. In this study, targets were obtained by electroplating onto a gold backing and a typical target irradiation uses 200ߙnA, 17ߙMeV protons during 30ߙmin. After irradiation, pure copper-64 is obtained using only one chromatographic column. Nickel-64 is removed in a first elution step and cobalt isotopes in a second one. The extraction yield for copper-64 is 9±23% and nickel and cobalt impurities are under the detection limit. A recovery process of nickel-64 has also been developed.

SIMULATIONS ON NICKEL TARGET PREPARATION AND SEPARATION OF Ni(II)-

SIMULATIONS ON NICKEL TARGET PREPARATION AND SEPARATION.OF Ni(II)-Cu(II) MATRIX FORPRODUCTION OF RADIOISOTOPE64Cu64Ni (p,n) 64 and retained on the column while the nickel was kept in the form of Ni2+ 2+ 2+ and CuCl while the nickel was totally in the form of Ni2+ while the nickel was found as both Ni2+ and NiCl while the nickel was mostly in the form of Ni2+. The retained CuCl was then changed back into Cu2+ Keywords 64 Cu, Anion exchange chromatography.: Nickel target preparation, Radioisotope Cu-64, Separation of Ni(II)-Cu(II) matrix, Nuclear reaction of 64Ni(p,n) cation form andeluted out the column by using HCl 0.05 M. The 42– 4 2–.The best condition of separation was in HCl 8 M in which the radioactive copper was mostly in the form of CuCl 42– 42– . In the condition ofHCl 9 M, the radioactive copper was mostly in the form of CuCl 42– cation. It was found that the electroplating result from the acidic solution was more satisfied than that from the basic solution. By conditioning the matrix solution at HCl 6 M, the radioactivecopper was found in the forms of Cucation and eluted off from the column. The retained radioactive copper was then eluted out the column in the condition of dilute HCl changingback the copper anion complex into Cu42– Cu. The nickel target preparation was performed by means of electroplating method using acidic solution of nickel chloride - boric acid mixture and basic solution of nickel sulphate – nickel chloridemixture on a silver- surfaced-target holder. The simulated solution of Ni(II) – Cu(II) matrix was considered as thesolution of post-proton-irradiated nickel target containing both irradiated nickel and radioactive copper, but in thepresented work the proton irradiation of nickel target was omitted, while the radioactive copper was originallyobtained from neutron irradiation of CuO target. The separation of radioactive copper from the nickel target matrixwas based on anion exchange column chromatography in which the radiocopper was conditioned to form anioncomplex CuClg-spectrometric analysis showed a single strong peak at 511 keVwhich is in accord to g-annihilation peak coming from positron decay of Cu-64, and a very weak peak at 1346 keVwhich is in accord to g-ray of Cu-64.. The simulations on Nickel target preparation and separation of Ni(II)- Cu(II) matrix has been carried out as a preliminary study for production of medical radioisotope Cu-64 based onnuclear reaction of

Hadron Spectroscopy with COMPASS

The COmmon Muon and Proton Apparatus for Structure and Spectroscopy is a fixed target experiment at the CERN SPS accelerator. In the past two years hadron spectroscopy was brought into focus. A huge amount of data was taken, using hadronic beams at a momentum of 190 GeV/ c impinging on hydrogen, lead, nickel and tungsten targets. The primary goal for the hadron programme is the study of resonance production by diffractive scattering, central production and photon exchange. To bring clarity in the intriguing question about the existence of exotic states, such as glueballs and hybrids, the analysis of several channels have been started. We present here a selective overview of the current status.

Preparation and characterization of nickel targets for cyclotron production of 64Cu

The reaction route 64Ni(p,n)64Cu is very popular for the preparation of 64Cu because its entrance channel is accessible at low energies and yield of reaction is quite high. However, a high price of the enriched 64Ni is a disadvantage of this reaction path; hence, preparation of a chemically pure nickel targets for the production of 64Cu using COSTIS (Compact Solid Target Irradiation System) is of a great research interest. In this paper, effects of boric acid, composition of electrolytic bath and electrochemical process conditions on the quality of nickel films deposited on 2 mm thick gold or platinum disc targets were investigated. Chemical purity of the electrodeposited nickel was measured by the Auger electron spectroscopy and the surface quality of targets was studied microscopically (SEM). A SRIM program was used for a thickness target calculation. COSTIS target station was installed at the end of the external beam line of the IBA Cyclone 18/9 cyclotron, and the irradiation surface of target was optimized. The target station has been equipped with Al or Nb window foil in the front of the target to degrade the beam energy to an optimal value.

ESTIMATING NEUTRON DOSE EQUIVALENT RATES FROM HEAVY ION REACTIONS AROUND 10 MeV amu−1 USING THE PHITS CODE

It has been sometimes necessary for personnel to work in areas where low-energy heavy ions interact with targets or with beam transport equipment and thereby produce significant levels of radiation. Methods to predict doses and to assist shielding design are desirable. The Particle and Heavy Ion Transport code System (PHITS) has been typically used to predict radiation levels around high-energy (above 100 MeV amu(-1)) heavy ion accelerator facilities. However, predictions by PHITS of radiation levels around low-energy (around 10 MeV amu(-1)) heavy ion facilities to our knowledge have not yet been investigated. The influence of the "switching time" in PHITS calculations of low-energy heavy ion reactions, defined as the time when the JAERI Quantum Molecular Dynamics model (JQMD) calculation stops and the Generalized Evaporation Model (GEM) calculation begins, was studied using neutron energy spectra from 6.25 MeV amu(-1) and 10 MeV amu(-1) (12)C ions and 10 MeV amu(-1) (16)O ions incident on a copper target. Using a value of 100 fm c(-1) for the switching time, calculated neutron energy spectra obtained agree well with the experimental data. PHITS was then used with the switching time of 100 fm c(-1) to simulate an experimental study by Ohnesorge et al. by calculating neutron dose equivalent rates produced by 3 MeV amu(-1) to 16 MeV amu(-1) (12)C, (14)N, (16)O, and (20)Ne beams incident on iron, nickel and copper targets. The calculated neutron dose equivalent rates agree very well with the data and follow a general pattern which appears to be insensitive to the heavy ion species but is sensitive to the target material.

Deposition and characterization of NiO x coatings by magnetron sputtering for application in dye-sensitized solar cells

Nickel oxide (NiO x ) due to its p-type nature has considerable potential as a photocathodic material in energy conversion devices such as dye-sensitized solar cells (DSSCs). However, NiO x has not been extensively used for this application mainly because of low light harvesting efficiency due to limited dye loading on the coatings. In this study NiO x coatings were deposited using the dc-magnetron sputtering technique from a nickel target in an argon/oxygen plasma. One of the advantages of magnetron sputtering is the ability to control coating properties such as mechanical performance and chemical stoichiometry. It is anticipated that by enhancing the interconnectivity between NiO x particles and by optimizing surface roughness, it may be possible to enhance dye adsorption and increase its ability to absorb visible light. NiO x coatings were deposited onto both silicon wafer and indium tin oxide (ITO) covered glass substrates. The influence of deposition parameters such as pressure, nickel target current and substrate bias voltage were correlated with the coating properties of surface roughness, thickness, crystallographic structure and surface energy. This evaluation was carried out using optical profilometry, spectroscopic ellipsometry, XRD and contact angle measurements respectively. It was observed that deposited coating morphology and roughness were significantly influenced by the deposition parameters. For example increasing the deposition pressure from 0.20 to 0.40 Pa led to an increase in surface roughness (Ra) from 1.6 to 3 nm. Associated with this increase in roughness the surface energy increased from 36 to 61 mN/mm. The NiO x coatings were spectrally sensitized with Ru-complex dye containing –COOH groups as anchoring moieties. The dye adsorptions on NiO x coatings, deposited on ITO substrates, were investigated in transmission mode using UV–vis spectroscopy in the range of 400–800 nm. It was observed that for the coatings with the highest surface energy, there was an increase of up to 60% in the level of dye adsorption. The electroactivity of the NiO x thin films deposited on Ni substrate at 0.4 Pa has been verified through the occurrence of redox processes of reduction and lithium intercalation within the oxide film.

Nickel containing diamond like carbon thin films

Diamond like carbon (DLC) coatings are well established for multiple applications. The electrical conductivity of DLC or amorphous carbon can be influenced by several orders of magnitude via doping with different metals. Depending on the deposition process hydrogen may be incorporated as well, thereby decreasing the conductivity. Recent investigations of DLC disclose nice piezoresistive properties. Our work was focused on Ni:a-C:H thin films on different substrates by reactive sputtering from a nickel target. Several carbon precursors were added to the sputtering gas to create an amorphous carbon hydrogen network with embedded crystal clusters. In order to optimize the piezoresistive properties we varied various process parameters. The piezoresistive response was monitored by measuring the resistance change during bending. Our Ni:a-C:H films develop gauge factors of approx. 12 in a wide range of process parameters. For sensor applications the temperature coefficient of resistance (TCR) is important as well. It depends on the metal concentration in the thin film and can be adjusted by the concentration of the incorporated nickel. It can be set to approximately zero in a wide temperature range of 80–400 K. The combination of a high gauge factor and a very small TCR is achieved and described in this paper. XRD measurements reveal nickel or nickel carbide clusters with diameters of approx. 8–30 nm depending on the metal concentration. The clusters crystallize in the hexagonal hcp structure which could be transformed into the cubic fcc structure of nickel by thermal annealing in a vacuum.

Preparation and Evaluation of [55Co](II)DTPA for Blood Cell Labeling

Co-55 (T1/2=17.53 h) was produced by 150 μA irradiation of a natural nickel target by 15 MeV protons and was separated from the irradiated target material by two ion exchange chromatography steps and was used for the preparation of ( 55 Co)diethylenetriaminepentacetate (( 55 Co)DTPA). Optimization studies were performed using Co-57 due to its longer half-life. Cobalt-57 (T1/2=271.79 d) was produced by irradiation of a natural nickel target with 150 μA current of 22 MeV protons. The 57 Co was separated from the irradiated target material using a no carrier added method with a radiochemical yield of >97%. The 55 Co was separated from the irradiated target material using a two step method with a radiochemical yield of >95%. Both products were controlled for radionuclide and chemical purity. The solutions of ( 55 Co)complex were prepared (radiochemical yield>80%) starting with 55 CoOAc ligand at room temperature after 30 min. RTLC showed the radiochemical purity of more than 99%. Specific activity was obtained about 9.1 TBq/mmol. The tracer showed to be sta- ble in the final product and in the presence of human serum at 37°C up to 15 h. ( 55 Co)DTPA was successively used in the radiolabeling of red blood cells for PET 1 diagnostic studies. 1408(16.8%), 1369(2.9%), 1316(7.0%), 931(75%), 803(1.8%), 477(20.2%) 411(1.0%), 91(1.1%) and 511(154%) � + (60%), E.C.(40%)

Preparation and preliminary evaluation of [ 55Co](II)vancomycin

Co-55 ( t 1/2=17.53 h) was produced by 150 μA irradiation of a natural nickei target using 15 MeV protons. It was separated from the irradiated target material by two ion exchange chromatography steps with a radiochemical yield of >95% and was used for the preparation of [ 55Co]vancomycin ([ 55Co]VAN). Optimization studies were performed using Co-57 due to its longer half-life. Cobalt-57 ( t 1/2=271.79 d) was produced by irradiation of a natural nickel target with 150 μA current of 22 MeV protons. The 57Co was separated from the irradiated target material using a no-carrier-added method with a radiochemical yield of >97%. Both products were controlled for radionuclide and chemical purity. The solutions of [ 55Co]VAN were prepared (radiochemical yield >80%) starting with 55Co acetate and vancomycin at room temperature after 30 min. A precise solid phrase extraction (SPE) method was developed using Si Sep-Pak in order to purify/reconstitute the final formulation for animal studies. [ 55Co]VAN showed a radiochemical purity of more than 99%. The resultant specific activity was about 1.15 TBq/mmol. It is proved that the tracer is stable in the final product and in presence of human serum at 37°C up to 24 h. Biodistribution study of [ 55Co]VAN in normal rats was undertaken for up to 72 h.

Determination of the anomalous scattering factors of high-Z atoms using bremsstrahlung radiation

The anomalous scattering factors (f′ and f″) of tungsten, gold and lead atoms have been determined using external bremsstrahlung (EB) photons. The EB photons are produced by the interaction of a beta particle from a beta source with a nickel target. These photons are allowed to pass through thin targets of tungsten, gold and lead. The transmitted photons have been measured by using a GMX-type HPGe detector coupled to an 8K multichannel analyser. The transmitted spectra show a sharp decrease in intensity at the K shell binding energies of the target atoms. The regions around the decreased portion have been used to determine the anomalous scattering factors. The experimentally measured values are compared with the available theoretical values.

An Evaluation of Abrasive Waterjet Peening With Elastic Prestress

Abrasive waterjet peening (AWJP) has been conceived as a new surface treatment process capable of achieving desired changes in surface texture, chemistry, and residual stress simultaneously. In the present investigation, the influence of elastic prestress on the residual stress resulting from AWJP was studied. Treatments were conducted on steel, as well as nickel and titanium alloy targets subjected to an elastic prestress ranging from 0% to 75% of the material’s yield strength. The results showed that a tensile elastic prestress increases the surface residual stress and the depth of the compressive stress zone. The surface residual stress in each metal increased nonuniformly with magnitude of prestress; the maximum surface residual stress was obtained at an applied prestress between 45% and 60% of the substrate yield strength. Overall, the increases in surface stress and depth that were obtained reached 100% and 50%, respectively. There were no changes to the surface texture caused by the prestress. According to results of this study, application of an elastic prestress can serve as an effective method for improving characteristics of the residual stress field in components treated using AWJP.

Preparation and Biological Evaluation of a [55Co]-2-Acetylpyridine Thiosemicarbazone

Due to the anti-proliferative properties of cobalt-thiosemicarbazone complexes, the production of [55Co](III)-bis-(2-acetylpyridine thiosemicarbazone) ([55Co](III)[APTS]2) was investigated. Co-55 (T1/2=17.53 h) was produced by 150 μA irradiation of a natural nickel target by 15 MeV protons. The 55Co was separated from the irradiated target material using a two-step method with a radiochemical yield of >95% followed by radionuclidic and chemical purity control. [55Co](III)chloride was mixed with 2-acetylpyridine thiosemicarbazone for 30 min at room temperature to yield [55Co](III)[APTS]2 (radiochemical purity > 98% shown by RTLC/HPLC). A specific activity of about 10–20 Ci/mmol was obtained. The final solution was diluted in normal saline to 5% ethanolic solution for biological evaluation. The stability of the final product was checked in the absence and presence of human serum at 37°C to 24 h. The partition co-efficient of the final complex at the pH of 7 was 1.00±0.08. A significant tumor accumulation (%ID/g; 3.5%) was observed in tumoral tissue 21 h post injection in fibrosarcoma-bearing mice by biodistribution studies. Co-incidence imaging also demonstrated tumor uptake from 21–35 h however at 35 h tumor uptake is more specific and significant.