Marking actinides for separation: Resonance-enhanced multiphoton charge transfer in actinide complexes.

Precise separation and purification of f-block elements are important and challenging especially for the reduction of nuclear waste and the recycling of rare metals but are practically difficult mainly because of their chemical similarity. A promising way to overcome this difficulty is controlling their oxidation state by nonchemical processes. Here, we show resonance-enhanced multiphoton charge transfer in actinide complexes, which leads to element-specific control of their oxidation states owing to the distinct electronic spectra arising from resonant transitions between f orbitals. We observed oxidation of trivalent americium in nitric acid. In addition, we found that the coordination of nitrates is essential for promoting the oxidation reaction, which is the first finding ever relevant to the primary process of photoexcitation via resonant transitions of f-block elements. The resonance-enhanced photochemical process could be used in the nuclear waste management, as it would facilitate the mutual separation of actinides, such as americium and curium.

Aggregation Behavior and Thiol-Thioester Exchange for Cationic Surfactants with Propylthioacetate Side Chain.

A series of cationic surfactants containing the thioacetate group, [CnH2n+1N(CH3)2(CH2)3SCOCH3] Cl (Cn3SAc, n = 12, 14, 16), were prepared and their properties in aqueous solution were investigated by conductivity, fluorescence, and dynamic light scattering measurements. The critical micelle concentrations (CMCs) of Cn3SAc decreased to about half the value of the corresponding alkyltrimethylammonium chloride. Thioacetate was eliminated with the addition of dithiothreitol (DTT) as well as NaOH. HPLC (high performance liquid chromatography) analysis and NMR (nuclear magnetic resonance) spectroscopy showed that thiol surfactants, [CnH2n+1N(CH3)2(CH2)3SH]Cl (Cn3SH), were generated upon the addition of DTT in aqueous solution via thiol-thioester exchange, whereas gemini surfactants, [CnH2n+1N(CH3)2(CH2)3SS(CH2)3N(CH3)2CnH2n+1]2Cl (2Cn3SS), were generated upon incubation in alkaline solution via hydrolysis and air oxidation.

Proposed Cesium-free Mineralization Method for Soil Decontamination: Demonstration of Cesium Removal from Weathered Biotite.

The removal possibility of sorbed Cs from weathered biotite (WB), which is considered a major Cs adsorbent in the soil of Fukushima, has been investigated by the addition of an NaCl-CaCl2 mixed salt powder with a 1:1 ratio of Na and Ca and subsequent heat treatment under a reduced pressure of 14 Pa. X-ray fluorescence analysis was used to determine the Cs removal rate at elevated temperatures. The structural changes and new phases formed were determined using powder X-ray diffraction as well as electron diffraction and X-ray microanalysis in a transmission electron microscope. We found that Cs was completely removed from the specimen heated at 700 °C, where WB completely decomposed and augite was formed. On the basis of this finding, we propose the Cs-free mineralization method as a new soil-decontamination process in which Cs minerals are transformed by heating with certain additives into minerals that cannot incorporate Cs.

Mechanism of Cs Removal from Fukushima Weathered Biotite by Heat Treatment with a NaCl-CaCl2 Mixed Salt.

An in situ extended X-ray absorption fine structure (in situ EXAFS) spectroscopic analysis at high temperature was conducted to investigate the mechanism of Cs removal from weathered biotite (WB) from Fukushima, induced by heating with a mixed salt of NaCl and CaCl2. This indicated that most Cs remained in WB during heating at 200-700 °C. In addition, the in situ EXAFS spectra gradually changed on heating with the mixed salt and a completely different spectrum was observed for the sample after cooling from 700 °C to room temperature (RT). Ex situ EXAFS measurements and X-ray fluorescence analyses were also conducted on samples after heat treatment and removal of the mixed salt to clarify the temperature dependence of the Cs removal ratio. On the basis of the results of radial structure function analysis obtained from in situ EXAFS, we concluded that almost all of the Cs was removed from WB by heating at 700 °C with the mixed salt, and that Cs formed Cs-Cl bonds after cooling to RT from 700 °C. In contrast, although more than half of the Cs present was removed from WB by heat treatment at 500 °C, most Cs was surrounded by silica tetrahedrons, maintained by Cs-O bonds. On the basis of these results, different Cs removal processes are suggested for the high-temperature (600-700 °C) and low-temperature (400-500 °C) regions.

Characteristics of 20 Patients with Autochthonous Acute Hepatitis E in Hokkaido, Japan: First Report of Bilateral Facial Palsy Following the Infection with Genotype 4 Hepatitis E Virus.

Autochthonous hepatitis E is increasingly being recognized in industrialized countries, including Japan. Although neurological abnormalities have been sporadically reported as an extrahepatic manifestation of hepatitis E virus (HEV) infection, it is rare and has not been reported in Japan. The present study aimed to characterize a total of 20 patients consecutively diagnosed with sporadic acute hepatitis E at a city hospital in Hokkaido, Japan, during 2001-2014, focusing on a patient complicated with neuropathy. Seventeen patients were infected with genotype 4 HEV, while the remaining three patients were with genotype 3 HEV. Although a 67-year-old male with severe hepatitis did not have predisposing factors associated with the development of neurological disorders, such as diabetes mellitus and the use of immunosuppressive agents, he developed bilateral peripheral facial palsy six days after admission. A neurological examination revealed the inability to smile, frown, close his eyes completely or puff out his cheeks. MRI brain scans were considered to be normal. Although it took 83 days after admission for the total bilirubin levels to normalize, his neurological symptoms resolved gradually within three weeks without any sequelae following conservative therapy. A full-length genomic analysis of the HEV strain (HE-JA30) isolated from the patient belonged to genotype 4 and was closest to that currently circulating in Hokkaido, Japan. This is the first report of HEV-associated neuropathy in Japan. While all of previous reports on HEV-related neuropathy involve genotype 3 HEV, the present report is unique in that genotype 4 HEV is responsible for the neuropathy.

5-Isopropyl-5-methyl-2-sulfanylidene-imidazolidin-4-one.

In the title compound, C7H12N2OS, the 2-sulfanylideneimidazolidin-4-one moiety is nearly planar, with a maximum deviation of 0.054 (2) Å. In the crystal, a pair of N-H⋯O hydrogen bonds and a pair of N-H⋯S hydrogen bonds each form a centrosymmetric ring with an R 2 (2)(8) graph-set motif. The enanti-omeric R and S mol-ecules are alternately linked into a tape along [1-10] via these pairs of hydrogen bonds.

1-Acetyl-5-(4-fluoro-phen-yl)-2-sulfanyl-ideneimidazolidin-4-one.

In the title compound, C11H9FN2O2S, the 2-sulfanylideneimidazolidin-4-one moiety is essentially planar, with a maximum deviation of 0.0183 (14) Å. The mean plane of this moiety is approximately coplanar with the attached acetyl group and perpendicular to the benzene ring, making dihedral angles of 9.70 (14) and 86.70 (6)°, respectively. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds between the amide NH and acetyl C=O groups, forming a C(6) chain along the a-axis direction.

Chemical-state-selective mapping at nanometer scale using synchrotron radiation and photoelectron emission microscopy.

For surface analyses of semiconductor devices and various functional materials, it has become indispensable to analyze valence states at nanometer scale due to the rapid developments of nanotechnology. Since a method for microscopic mapping dependent on the chemical bond states has not been established so far, we have developed a photoelectron emission microscopy (PEEM) system combined with synchrotron soft X-ray excitation. The samples investigated were Si/SiO(x) micro-patterns prepared by O(2)(+) ion implantation in Si(001) wafer using a mask. PEEM images excited by various photon energies around the Si K-edge were observed. The lateral spatial resolution of the system was about 41 nm. The brightness of each spot in PEEM images changed depending on the photon energy, due to the X-ray absorption intensity of the respective chemical state. Since the surface of this sample was topographically flat, it has been demonstrated that the present method can be applied to observations of the microscopic pattern, depending not on the morphology, but only on the valence states of silicon. We have also in-situ measured the changes of the PEEM images upon annealing, and elucidated the mechanism of the lateral diffusion of oxygen and valence states of silicon at the nanometer scale.

Atypical mucosa-associated lymphoid tissue lymphoma in the transverse colon associated with macroglobulinemia.

We herein present a quite atypical case of primary gastrointestinal mucosa-associated lymphoid tissue (MALT) lymphoma in the transverse colon. Computed tomography and endoscopic ultrasonography revealed diffuse thickening of the wall, and colonoscopy showed a white-colored mucosa with reduced superficial vessels in the entire transverse colon. The lesion was diagnosed as MALT lymphoma by pathological examination of the biopsied specimen. Secondary macroglobulinemia of IgM-kappa type was also found in the present case. After chemotherapy and radiation, the lesions in the transverse colon improved and the patient has been in good condition without any evidence of recurrence for more than 1 year.

A case in which danaparoid sodium was effective for portal venous thrombosis developed after endoscopic injection sclerotherapy for esophageal varices.

We report a case of hepatitis C type liver cirrhosis with portal venous thrombosis in which danaparoid sodium was very effective. The patient developed portal venous thrombosis, esophageal ulcer, and esophageal stenosis at the same time after sclerotherapy. Since it was confirmed by abdominal computed tomography that there was no portal venous thrombosis before sclerotherapy, development of the thrombosis was considered to be associated with sclerotherapy. The patient was treated with balloon dilation therapy for esophageal stenosis, and with anticoagulation therapy using danaparoid sodium for portal venous thrombosis. The portal venous thrombosis disappeared 4 weeks after the treatment. Despite the condition of esophageal ulcer being caused by sclerotherapy, the patient was safely treated without any adverse effects and complications, and the clinical course has been good. It was indicated that danaparoid sodium was an anticoagulant unlikely to cause adverse effects such as hemorrhage and might be an effective drug for treatment of portal venous thrombosis.

[Treatment by danaparoid sodium for portal venous thrombosis].

We report a case of hepatitis B type liver cirrhosis with portal venous thrombosis in which danaparoid sodium was very effective. The portal venous thrombosis in this case disappeared 2 weeks commencing after administration of danaparoid sodium. The patient had not adverse effects or complications such as hemorrhage, and the clinical course was good. We consider that danaparoid sodium is an anticoagulant unlikely to cause adverse effects such as hemorrhage, and that it might be effective for treatment of portal venous thrombosis. We intend to examine the indications of treatment with danaparoid sodium, clarify the best administration method, and establishment of maintenance therapy by investigating more cases.