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Pure lithium hexafluorophosphate (LiPF6) has been successfully prepared by the reaction between the elemental fluorine and the equi-molar mixture of LiF and P (F2 direct method). The product was pure enough to be used as an electrolyte salt of lithium secondary battery. Especially, the stepwise introducing of fluorine gas into a reaction system was effective to prepare LiPF6 in a high yield. The results of Rietveld refinement of XRD data revealed that the structure of LiPF6 was trigonal (R3, Z = 3, a0 = 0.4932(2), c0 = 1.2641(5)nm, cell volume; 2.663(2) x 10-28 m³). The cell constants of LiPF6 prepared by the F2 direct method were almost the same as those of LiPF6 prepared by the reaction between LiF and PF5 in a liquid anhydrous hydrogen fluoride (L-AHF method). [ABSTRACT FROM AUTHOR]

An abstract of the article "Preparation of Pure LiPF6 Using Fluorine Gas at Room Temperature," by Jae-ho Kim and colleagues is presented.

Abstract: LiMF6 (M=Ta, Nb) was prepared by the reaction between LiF and MF5 (M=Ta, Nb) in F2 gas. Pure LiMF6 (M=Ta, Nb) salts were obtained by using the reaction at temperatures higher than 473K under 80kPa (F2) for 24h. The x values in LiMF x (M=Ta, Nb) were confirmed as 5.7–6.0 by XRD–Rietveld analysis. Results showed that LiMF6 (M=Ta, Nb) has a trigonal structure (, Z =3). The respective lattice parameters of LiTaF6 and LiNbF6 are a 0 =0.533nm, c 0 =1.362 and a 0 =0.532nm, c 0 =1.360. The equivalent conductivities of both LiMF6 (M=Ta, Nb) in propylene carbonate (PC) are equal at 15.2Ω−1 cm2 mol−1 at 0.01moldm−3. The electrochemical potential window of TaF6 − is 7.0V, which is 0.4 and 0.2V wider, respectively, than those of BF4 − and PF6 −. [Copyright &y& Elsevier]

Abstract: New oxide fluoride glasses containing HoF3 was successfully prepared in the glass system of HoF3–BaF2–AlF3–GeO2 in which the maximum content of HoF3 reached approximately 50mol% as the nominal composition. Glass transition temperatures, densities and refractive indices of the prepared glasses with various HoF3 contents were 572.3–614.4°C, 4.45–6.45×103 kgm−3 and 1.58–1.68, respectively. Absorption and the fluorescence spectra were measured for the glasses with HoF3 contents of 10–50mol%. The profiles of the absorption and the fluorescence spectra were influenced by the content of HoF3. Especially, the intensity ratio of the fluorescence spectra at 550 and 660nm changed drastically with the contents of HoF3 in the glasses. The experimental results were analyzed in the frame of the Judd–Ofelt theory. [Copyright &y& Elsevier]

Abstract: The electrochemical properties and thermal stability of carbon coated LiFePO4 cathode were improved by the surface fluorination using NF3 gas at a pressure less than 6.67kPa at 25°C. Especially, in case of F1-LiFePO4, the discharge capacity was about 10% higher than that of untreated LiFePO4. Also it indicated the lowest resistance (R ct =35.55Ω) and largest exchange current density (i 0 =0.72mA) from the EIS results. However, in case of F2-LiFePO4, the electrochemical properties were negatively affected by the formation of some resistive fluoride films. In terms of thermal stability, the decomposition temperature (222.0°C) of F1-LiFePO4 was 14°C higher than that of untreated LiFePO4. Therefore, the surface fluorination led to the improvement of electrochemical properties and thermal stability of LiFePO4 as a promising cathode in high power lithium-ion cells for HEVs. [Copyright &y& Elsevier]

Abstract: The dispersion stability and photocatalytic activity of TiO2 particles were improved by the surface fluorination using fluorine gas (F2) at a pressure less than 50.5kPa at 25°C. Average particle sizes and zeta potentials of fluorinated TiO2 (F-TiO2) particles in all solvents were approximately 11 times smaller and 1.5 times larger, respectively, than those of untreated TiO2 particles (2.5×103 nm and −19mV). In the photocatalytic activity of TiO2, the UV–vis absorption range of F3-TiO2 with Ti3+ and Ti2+ valences expanded to about 500nm. Also, the degradation ratio of methylene blue (73%) with F-TiO2 was much higher than that (18%) with untreated TiO2 at 4h. However, TiOF2 in F4-TiO2 synthesized at 200°C severely affected the dispersion stability and the photocatalysis of TiO2. To optimize the beneficial effects of surface fluorination considering the dispersion stability and photocatalytic activity, it is necessary to control the fluorine content (x), 0< x <0.5 in TiO2−x F2x . [Copyright &y& Elsevier]

Abstract: Cerium-containing oxide fluoride glasses CeF3–BaF2–AlF3–SiO2 were prepared under CO and Ar atmospheres. The glass prepared in a CO atmosphere exhibited blue emission under UV irradiation because the hydrolysis of CeF3 to a Ce4+-containing compound during heating process was controlled. The emission spectrum was separable into three peak components by peak analysis. X-ray photoelectron spectroscopy (XPS) spectra were measured to investigate the valency of the elements in the glass. Oxide and fluoride ions in the glass respectively have different electronic states from those in CeO2 and CeF3. The electronic state of cerium ion in the oxide fluoride glass differed from that in CeO2 and CeF3. [Copyright &y& Elsevier]

Abstract: Tetragonal PbSnF4 was prepared by precipitation method with Pb(NO3)2 and SnF2 aqueous solutions. The product was characterized using X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XFS), and the other chemical analyses. Tetragonal PbSnF4 exhibited the highest electric conductivity of 3.2Sm−1 at 473K in air as a fluoride ion conductor. We have investigated the possibility of COF2 formation using CO2 and F2 in an electrochemical cell with PbSnF4 as a solid electrolyte. At same time, we tried to produce an electric power from an electrochemical cell. This CO2/F2 electrochemical cell was constructed with a tetragonal PbSnF4 disk having Au electrodes. The electromotive force was about 0.9V at room temperature for 0.1MPa CO2/(0.01MPa F2 +0.09MPa Ar). However, the short circuit current density was 0.24Am−2, which was quite small. This current density was so small that no fluorocarbon compound was detected after 3h discharge using FT-IR. [Copyright &y& Elsevier]

Abstract: The preparation of the rare earth containing oxide fluoride glasses LnF3 (Ln; Y through Lu)–BaF2–AlF3–GeO2 in which the nominal content of LnF3 reached 60mol% in maximum and their basic properties such as density, refractive index and glass transition temperature were investigated and summarized in detail. Especially, in order to discuss the local structure around the rare earth ion in the glass, the Judd–Ofelt analysis (discussion with Ω parameters) of the HoF3–BaF2–AlF3–GeO2 glasses was carried out. The unique fluorescent behavior and the magnetic properties of LnF3–BaF2–AlF3–GeO2 glasses (Ln=Tb and/or Sm) were also studied. [Copyright &y& Elsevier]

Abstract: The AB5-type hydrogen storage alloy (MH alloy) could be deposited uniformly with Ni-PTFE composite layer using the electroplating method. The thickness of Ni-PTFE composite layer was controlled to 1–2μm and the Ni and PTFE amounts were 8wt.% and 2–4wt.%, respectively. The Ni-PTFE composite layer on MH alloy improved the electrochemical property, especially quick activation as well as the corrosion resistivity of an original MH alloy. Especially the PTFE particles in the Ni-PTFE composite layer play a role to create the interface reaction fields of three phases of hydrogen gas–alloy–electrolyte solution. [Copyright &y& Elsevier]

Abstract: New glasses containing TbF3 have been prepared in a TbF3–BaF2–AlF3–GeO2 system. Their respective densities, refractive indexes, and glass transition temperatures are (5.42–6.07)×103 kgm−3, 1.72–1.73, and 605.1–675.2°C. Their magnetic susceptibilities are proportional to the contents of TbF3 in glasses obtained in this study. The values agree with the calculated values. The Curie constant of the 40TbF3–20BaF2–10AlF3–20GeO2 glass is 5.13Kemumol−1; its effective magnetic susceptibility is 9.96μ B. The atomic percentage of Tb3+ in the 40TbF3–20BaF2–10AlF3–20GeO2 glass is 11%, which is comparable to that of the oxide glass, which is reported as the material for Faraday components. [Copyright &y& Elsevier]

Multimodality therapy incorporated with radiotherapy, surgery and chemotherapy are used in the treatment of head and neck cancer in order to improve the local control and survival rate. TS-1, a newly developed oral antitumor agent which could achieve the same therapeutic concentration as that of 5-FU under continuous and intravenous treatment, has been used as adjuvant therapy for carcinomas in recent years. We presented our experience applying a new regimen of TS-1 and its side effects. TS-1 has been applied for head and neck carcinomas since 2001. The oral application of TS-1 has been used in 32 cases of head and neck cancer in our department since 2003, and the agent has been applied in 22 of 32 cases as adjuvant therapy. The primary sites of malignancy included hypopharyngx (7 cases), larynx (6 cases), maxillary sinus (2 cases), oropharynx (2 cases), oral cavity (4 cases), submandibular gland (1 case) and one case in which the primary site was unknown. A regimen of four-week application followed by two-week rest had been used in 6 cases in the first part of this trial. However, a high frequency of blood toxicity was found from the third week, requiring alteration of the protocol. Thus, a new regimen of two-week application followed by one week rest was thereafter used in the other 16 cases. Blood toxicity was found in 66.7% of those cases receiving a four-week application followed by two-week rest regimen. In the 16 cases receiving the two-week application followed by one-week rest regimen, only one case showed grade 2 leucopenia while continuous application for more than eight weeks was possible in 9 cases. Mild macrocytic anemia was found in some of these cases, however none of which required any necessary interruption of the treatment. Side effects other than blood toxicity, such as edema or pigmentation of lower limbs, erythema of skin and diarrhea, were found in the other cases, requiring suspension of the treatment. But the subsequent application was possible after a break or decreasing the dosage. We concluded that the new regimen of two-week application followed by one-week rest is less likely to be interrupted by the side effects and is safer to be used outpatiently, compared with the four-week application followed by two-week rest.