Source Preparation Methods Research Articles

Reliable micro-transfer printing method for heterogeneous integration of lithium niobate and semiconductor thin films

High-speed Pockels modulation and second-order nonlinearities are key components in optical systems, but CMOS-compatible platforms like silicon and silicon nitride lack these capabilities. Micro-transfer printing of thin-film lithium niobate offers a solution, but suspending large areas of thin films for long interaction lengths and high-Q resonators is challenging, resulting in a low transfer yield. We present a new source preparation method that enables reliable transfer printing of thin-film lithium niobate. We demonstrate its versatility by successfully applying it to gallium phosphide and silicon, and provide an estimate of the transfer yield by subsequently printing 25 lithium niobate films without fail.

Alternate method of source preparation for alpha spectrometry: no electrodeposition, no hydrofluoric acid

An alternate method of preparing actinide alpha counting sources was developed in place of electrodeposition or lanthanide fluoride micro-precipitation. The method uses lanthanide hydroxide micro-precipitation to avoid the use of hazardous hydrofluoric acid. It provides a quicker, simpler, and safer way of preparing actinide alpha counting sources in routine, production-type laboratories that process many samples daily.

A Study of Simple α Source Preparation Using a Micro-coprecipitation Method

This study presents a rapid and simple source preparation method for a radioactive waste sample. The recovery of , and using a micro-coprecipitation method was over 95%. The -peak resolution of Pu and Am isotopes through the micro-coprecipitation method is enough to discriminate the Pu and Am isotopes from other Pu and Am isotopes. The determination of the Pu and Am isotopes using the micro-coprecipitation method was applied to the radioactive waste sample, so that the activity concentrations of the Pu and Am isotopes using the micro-coprecipitation method in the radioactive waste sample were similar to those using the electrodeposition method.

99Ru and 61Ni Mössbauer spectroscopic studies using the accelerator at RIKEN

Ruthenium and nickel are important constituent elements of a wide variety of compounds, including oxides, catalysts, and functional and industrial materials for solar butteries and shape-memory alloys. 99Ru and 61Ni Mössbauer spectroscopy can reveal significant information about the physical and chemical properties of these compounds. However, there have not been many studies that use Mössbauer spectroscopy to investigate Ru and Ni compounds. This paper discusses Mössbauer source preparation methods using the RIKEN accelerator for conventional Mössbauer absorption spectra in addition to our recent results.

Development of a rapid source preparation method for high-resolution α-particle spectrometry

In order to prepare sources of short-lived actinides for α-particle spectrometry, a coprecipitation method with Sm hydroxide was developed. The preparation procedure can be completed within 5 min with a high chemical yield of over 90%. It was found that the uniformity of the produced sources was sufficient to provide a high resolution of better than 20 keV. Under this method, we successfully measured the α-particle spectrum of short-lived Cf isotopes produced in the 238U( 12C, xn) reaction.

A Simple Source Preparation for Alpha-ray Spectrometry of Uranium and Thorium Isotopes

A simple source preparation method was developed for α-ray spectrometry to determine U and Th isotopes in silicate rock samples. Samples were decomposed by the mixed acid of HF-HCIO4-HNO3, and U and Th was isolated by use of UTEVA Spec. resin. Isolated U and Th were then extracted into TTA-benzene solution for purification. The organic phase was evaporated on a hot stainless steel planchet to dryness. This method is effective for the speedy preparation of thin sources of U and Th for α-ray spectrometry.

Application of MnO2-coated discs in the case of the measurement of226Ra with alpha-spectrometric method

Among the naturally occurring isotopes the determination of radium is the most difficult ones. In this work some alpha-spectrometric source preparation methods to determine radium were measured. The aim of our work was to investigate the feasibility of MnO2-coated discs for radium detection with a semi-conductor PIPS detector. This method based on the sorption of radium onto MnO2-coated surfaces. Parameters of this method were measured, and efforts were made to solve the incidental problems. In the case of using polyamide discs for base material, the executed experiments were showed that it might be applied to detection of 226 Ra, however the resolution was weak. It can be caused by the surface roughness and by the width of the MnO2 coat. In the consecutive investigates we have these parameters changed. Whereas the surface roughness of MnO2 cannot be changed more, smooth surfaces could produce in another way, so there were took several surfaces into account, like stainless-steel, nickel, copper and chrome plate. Regarding our results - in the case of optimal width of MnO2 coat - using MnO2-coated discs is a simple and effective source preparation method in radium measurement.

A standard to calibrate γ-ray spectrometers for gaseous samples

A standard is described which can be used to calibrate Ge(Li) detectors for measuring radioactive gaseous samples in 33-mL glass spheres. The method of source preparation can be applied to other types of counting bottles. The γ-ray energies of this source, 226Ra plus progeny, range from 46 to 1765 keV. The uncertainties in the emission rates for the various γ rays in the source are estimated to be about 3%. (6) The source has a half life of 1600 y and coincidence-summing corrections are minor.

Effect of source preparation technique on the differential angular correlation of the 133–482 keV cascade in 181Ta

By using a standardised method of source preparation and an ultra-fast coincidence circuit the differential angular correlation of the 133–482 keV cascade in 181Ta using sources of Hf(OH) 4 in HF, HClO 4, HCl, HNO 3, H 2SO 4, and CH 3COOH medium has been measured. The results are (1) no attenuation in HF, (2) λ 2=(4.0±0.3) × 10 7 s −1, λ 4=(6.6±2.8) × 10 7 s −1 in HClO 4, (3) λ 2=(7.8±0.3) × 10 7 s −1, λ 4(13.0±1.8) × 10 7 s −1 in HCl,(4) λ 2=(9.5±0.5) × 10 7 s −1, λ 4=(11.4±3.9) × 10 7 s −1 in HNO 3, (5) λ 2=(26.1±0.2) × 10 7 s −1 in H 2SO 4, and (6) a two-exponential decay in CH 3COOH medium with λ 1 2=(4.1±0.2) × × 10 8 s −1 and λ 2 2=(0.14±0.02) × 10 8 s −1. The experiments in HClO 4 and HNO 3 medium are new. The other results are compared with the nature and magnitude of the results obtained by other workers in terms of the chemistry of Hf-ions in solution.

A β-Ray Source Preparation Method by the Use of Backing Film Coated with Aluminum

放射能濃度の絶対測定における均一で自己吸収の少ないβ線源作成法を研究した。線源の作成は, アルミニウム蒸着線源支持膜を用いて行ない, この上に, 放射性核種の溶液を滴下し, いったん赤外線ランプで乾燥したのち, 蒸留水で再溶解しアンモニア雰囲気中で乾燥した。この方法で線源の均一化は, 作成過程で生ずるアルミニウム化合物の微粒子の働きで行なわれた。作成した線源試料の均一性の評価は, 顕微鏡写真, オートラジオグラムを用いて行なった。また, 自己吸収量は, 46Sc, 60Co, 203Hgの3つの核種で試料を作成し, 4πβ-γ同時計数法により測定した。この結果, おのおのの核種で沈殿法, コロイダルシリカ処理法と同程度の値が得られた。

Perturbations of alpha-gamma angular correlations in the decay of230U and226Th

Perturbations of α-γ angular correlations in the decay of230U and226Th, involving the 2+ states in226Th and222Ra, have been studied using230U sources prepared by evaporation of the activity on Al foils, and226Th sources, prepared by collecting recoil nuclei from a230U source on Al foils. In vacuum, perturbation coefficients are found to be in agreement with the “hard-core-value” for static magnetic interaction. The perturbations in aluminum are found to be strongly dependent on the method of source preparation.

The self-absorption of Auger electrons and X-rays in Mn 54 sources prepared by different methods

The self-absorption of the 5 keV Auger electrons of Cr emitted after Mn 54 decay has been determined for sources prepared by seven different methods and on four different support materials. The lowest self-absorption of the Auger electrons, i.e. approximately 2%, has been found in sources prepared by vacuum evaporation. Sources obtained with other methods like electrodeposition, electrospraying and simple evaporation of a drop, show about 15, 25 and 50% self-absorption, respectively. Furthermore the measured Auger electron intensities depend considerably on the roughness of the support material. A calculation using a simple model shows that in very thin sources the ratio of the self-absorption of the Auger electrons and the X-rays is in a first approximation independent on the layer thickness of the source. This makes possible an estimate of the self-absorption of the X-rays from that of the Auger electrons, which is found to be 0·1–4% depending on the method of source preparation used.