In order to evaluate the efficiency of seaweed biomass as sorbent for rare earth elements(REEs), sorption experiment from aqueous solutions containing known amount of lanthanide(La, Eu or Yb) using three kinds of Ca-loaded dried seaweeds(brown algae:Sargassum hemiphyllum, green algae:Ulva pertusa and red algae:Schizymenia dubyi) in single component system was explored. Furthermore, the sorption mechanism of these elements was investigated by applying Langmuir and Freundlich isotherm equations to the data obtained. In addition, to confirm the characteristics of the seaweed biomasses, the surface morphology of the biomass before and after metal adsorption was determined by Scanning Electron Microscope(SEM). Consequently, the following matters have been mainly clarified. (1)The morphology of Sargassum hemiphyllum and Ulva pertusa surface has hardly changed even after exposing to metals. On the other hand, the change of the surface condition on Schizymenia dubyi after adsorption was observed. (2)Adsorption isotherms using the seaweed biomass can be described by Langmuir and Freundlich isotherms satisfactorily for lanthanide. These adsorption may have occurred mainly by monolayer reaction because of better-fitting for Langmuir model. (3)The seaweed biomasses could be an efficient sorbent for REEs. Particularly, Ulva pertusa is found to be a promising biosorbent for removing La. (4)Ion-exchange process is considered to be the main mechanism responsible for the sorption of lanthanide ion onto the seaweed biomass.
Nuclear Magnetic Resonance(NMR) is widely used method for metabolic analysis in biological systems. This would be attributed to the characteristic features of NMR;1) that's sample can be applied for various physical states, such as gases/solutions/solids, and including non-invasive measurements for cells/tissues/organs/individuals;2) although its information has selectivity in atomic level, observed spectra contains tremendous information regarding molecular structure, dynamics and quantities. In this review, we tried to discuss how technology developments of stable isotope labeling and its efficient analysis of multi-dimensional NMR spectra can contribute for promotion of metabolic analysis, like as protein NMR developed similar manner during the last century.
Purpose:There has been no guide of authorized radiological protection system in Japan when volunteers receive radionuclide administration in clinical research or phase I — IV studies. The purpose of this report was to depict issues on institutional radiological protection system for establishing the guide. Subjects and Methods:We accumulated full-filled questionnaires regarding institutional radiological protection system of human subjects in 82 hospitals in which clinical researches or phase I — IV studies underwent to be subjected to radionuclide administrated volunteers in recent two years. We analyzed regarding (1) research content, (2) what committee approval of research using radionuclide administrated volunteer, (3) selection of the volunteers, (4) regulatory dose of administrated radionuclide, and (5) informed consent. Results:Normal volunteers are subjected in clinical researches as well as phase-I study and microdose study. The researches subjected to normal volunteers needed with approval of institutional ethic committee in 64(78%)hospitals, others than ethic committee in 9(10%), and unknown in 2(2%). In remaining 7(8%), both ethic and other committees were described. No one with radiological knowledge included the committees in 23 hospitals(28%),of 15 had no consultation system regarding radiological protection. In all hospitals, regulatory dose in human subjects is less than 50mSv and sufficient informed consent regarding the protection was obtained. Conclusions:In Japan, researches subjected to radionuclide administrated volunteers are performed by authorization of institutional ethic committees. Administrated radionuclide dose in them are less than upper limits of regulatory system of ICRP, USA and England because the committees include physicians, technologists and pharmaceutics with knowledge of radiological protection. But some hospitals have no committees authorize the research because they have no idea of authorized committees or cannot establish the committees. We recommend that improvement of institutional radiological protection system in such hospitals. If necessary, approval system with outside hospital-committees may be required. Furthermore, we hope that improvement the condition which no consensus of regulatory dose to the volunteers in hospitals.
The traveling waves reflect and refract at the well-defined interface between two different media. This phenomenon is known as optics in the case of visible light. Neutron has the wave character besides the particle nature; therefore, neutron also shows optical phenomena under the special condition, and it is called neutron optics. Neutron reflectometry as well as X-ray reflectometry is the most powerful and nondestructive tool to analyze the structure of buried interfaces in the films which have the internal layered structure. Structural information on such interfaces is a clue to develop the nanoscale science and technology.
A neutron reflectivity (NR) measurement has been widely recognized as an essential technique for structural analysis of material interfaces and thin films due to its high depth-resolution in a non-destructive manner. One of its advantages for soft interface researches is introduction of neutron contrast into soft matters without changing their physical properties much by deuterium labeling. Another is exploration of interfaces deeply buried inside materials, such as a solid/liquid interface, with a non-destructive manner owing to a unique feature of neutron with high transmissivity into materials. Applications of NR to several soft interfaces were selected and outlined from a standpoint of industrial importance: an interface between a liquid crystal and a polymer at high temperature, an interface of a polymer multi-layer device before and after operation, a model resist polymer thin film immersed in water, and an electrochemical interface under dynamic redox switching conditions during voltammetric cycling.