Solid
lithium and sodium closo-polyborate-based
salts are capable of superionic conductivities surpassing even liquid
electrolytes, but often only at above-ambient temperatures where their
entropically driven disordered phases become stabilized. Here we show
by X-ray diffraction, quasielastic neutron scattering, differential
scanning calorimetry, NMR, and AC impedance measurements that by introducing
“geometric frustration” via the mixing of two different closo-polyborate anions, namely, 1-CB9H10
– and CB11H12
–, to form solid-solution anion-alloy salts of lithium or sodium,
we can successfully suppress the formation of possible ordered phases
in favor of disordered, fast-ion-conducting alloy phases over a broad
temperature range from subambient to high temperatures. This result
exemplifies an important advancement for further improving on the
remarkable conductive properties generally displayed by this class
of materials and represents a practical strategy for creating tailored,
ambient-temperature, solid, superionic conductors for a variety of
upcoming all-solid-state energy devices of the future.
We calculated the site-site radial distribution functions for binary mixtures of tert-butyl alcohol (TBA) and water over the whole range of TBA molar fraction. The description uses the reference interaction site model (RISM) integral equation theory in the dielectrically consistent approach of Perkyns and Pettitt (DRISM), and the closure approximation of Kovalenko and Hirata (KH) providing appropriate description for association of polar molecular species of density ranging from gas to liquid. We employed the extended simple point charge (SPC/E) model for water, and the optimized potential for liquid simulations (OPLS) force field for TBA. The partial radial distribution functions obtained for the TBA-water mixture are in qualitative agreement with those available from neutron diffraction experiments and molecular dynamics simulations. It is found that hydrogen bonds between all species are enhanced with rise of the TBA concentration. The tetrahedrallike network of hydrogen bonding in dilute TBA aqueous solution gradually turns into the zigzag-like structure for a high TBA concentration. In dilute aqueous solution, TBA molecules cluster by the hydrophobic methyl groups, whereas their hydroxyl groups are incorporated into the water hydrogen-bonding cage surrounding the TBA aggregate. In concentrated TBA, water as well as TBA molecules associate into the zigzag-like hydrogen-bonding chains. The present work shows that the RISM/KH theory is able to qualitatively predict the association structure of alcohol-water liquid mixtures.
Thermodynamic, structural, and dynamic properties of heavy water (D(2)O) confined in mesoporous silica glass MCM-41 C10, C12, and C14 were investigated by differential scanning calorimetry, neutron diffraction, and neutron spin echo (NSE) measurements, respectively. The DSC data showed that no crystallization of D(2)O confined in C10 occurs in a temperature range between 298 and 180 K, and that crystalline ice is formed at 204 and 221 K for C12 and C14, respectively. For C10, the neutron radial distribution functions of confined D(2)O suggested a structural change in the supercooled state between 223 and 173 K. For C10 sample, it has been found that the tetrahedral-like water structure is partially enhanced in the central part of pores at 173 K. For all the samples, the intermediate scattering functions from the NSE measurements are fitted by the Kohlrausch-Williams-Watts stretched exponential function which implies that confined supercooled D(2)O exhibits a wide distribution of relaxation times. For C10, C12, and C14 samples, between 298 and 240 K, the relaxation times of supercooled D(2)O follow remarkably well the Vogel-Fulcher-Tamman equation; for C10 sample, below 240 K, the relaxation times of nonfreezing D(2)O show an Arrhenius type behavior. From the present experimental results on calorimetric, structural, and dynamic properties, it has been concluded that supercooled D(2)O confined in MCM-41 C10 experiences a transition from high-density to low-density hydrogen-bonded structure at around 229 K.
BackgroundSince a phase I clinical trial using three HLA-A24-binding peptides from TTK protein kinase (TTK), lymphocyte antigen-6 complex locus K (LY6K), and insulin-like growth factor-II mRNA binding protein-3 (IMP3) had been shown to be promising for esophageal squamous cell carcinoma (ESCC), we further performed a multicenter, non-randomized phase II clinical trial.Patients and methodsSixty ESCC patients were enrolled to evaluate OS, PFS, immunological response employing ELISPOT and pentamer assays. Each of the three peptides was administered with IFA weekly. All patients received the vaccination without knowing an HLA-A type, and the HLA types were key-opened at the analysis point. Hence, the endpoints were set to evaluate differences between HLA-A*2402-positive (24(+)) and -negative (24(−)) groups.ResultsThe OS in the 24 (+) group (n = 35) tended to be better than that in the 24(−) group (n = 25) (MST 4.6 vs. 2.6 month, respectively, p = 0.121), although the difference was not statistically significant. However, the PFS in the 24(+) group was significantly better than that in the 24(−) group (p = 0.032). In the 24(+) group, ELISPOT assay indicated that the LY6K-, TTK-, and IMP3-specific CTL responses were observed after the vaccination in 63%, 45%, and 60% of the 24(+) group, respectively. The patients having LY6K-, TTK-, and IMP3-specific CTL responses revealed the better OS than those not having CTL induction, respectively. The patients showing the CTL induction for multiple peptides have better clinical responses.ConclusionsThe immune response induced by the vaccination could make the prognosis better for advanced ESCC patients.Trial registrationClinicalTrials.gov, number NCT00995358
We previously identified three novel HLA-A24-restricted epitope peptides, which were derived from three cancer-testis antigens, TTK protein kinase (TTK), lymphocyte antigen 6 complex locus K (LY6K), and insulin-like growth factor (
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