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1.
Artículo en Inglés | MEDLINE | ID: mdl-37921809

RESUMEN

Interfacial materials design is critical in the development of all-solid-state lithium batteries. We must develop an electrode-electrolyte interface with low resistance and effectively utilize the energy stored in the battery system. Here, we investigated the highly resistive layer formation process at the interface of a layered cathode: LiCoO2, and a garnet-type solid-state electrolyte: Li6.4La3Zr1.4Ta0.6O12, during the cosintering process using in situ/ex situ high-temperature X-ray diffraction. The onset temperature of the reaction between a lithium-deficient LixCoO2 and Li6.4La3Zr1.4Ta0.6O12 is 60 °C, while a stoichiometric LiCoO2 does not show any reaction up to 900 °C. The chemical potential gap of lithium first triggers the lithium migration from the garnet phase to the LixCoO2 below 200 °C. The lithium-extracted garnet gradually decomposes around 200 °C and mostly disappears at 500 °C. Since the interdiffusion of the transition metal is not observed below 500 °C, the early-stage reaction product is the decomposed lithium-deficient garnet phase. Electrochemical impedance spectroscopy results showed that the highly resistive layer is formed even below 200 °C. The present work offers that the origin of the highly resistive layer formation is triggered by lithium migration at the solid-solid interface and decomposition of the lithium-deficient garnet phase. We must prevent spontaneous lithium migration at the cathode-electrolyte interface to avoid a highly resistive layer formation. Our results show that the lithium chemical potential gap should be the critical parameter for designing an ideal solid-solid interface for all-solid-state battery applications.

2.
Inorg Chem ; 62(46): 18830-18838, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37870946

RESUMEN

Layered LiCoO2 is usually synthesized after a prolonged sintering process at high temperatures (≥800 °C) for 10-20 h. This study developed a "hydroflux process" to obtain highly crystalline and layered LiCoO2 at a low temperature of 300 °C within 30 min. Molten mixed hydroxide-containing water molecules significantly accelerated the formation of LiCoO2, which showed a highly reversible capacity of 120 mAh g-1 without postannealing. The reaction mechanism study showed fast growth of LiCoO2 crystals, suggesting that the excess molten hydroxides containing water dissolve the cobalt species of HCoO2-. Consequently, the accelerated LiCoO2 formation suppresses the competing reaction of Co3O4 formation, leading to spinel LiCoO2 formation at low temperatures. Excess water in the starting materials further accelerated the crystal growth of LiCoO2, forming large particles (>1 µm). Moreover, the layered LiCoO2 began to form at 150 °C. This study is the first experimental demonstration that proves the thermodynamic stability of layered LiCoO2 at low temperatures (150-300 °C) under ambient pressure. This novel process offers significant energy savings in the production process of LiCoO2 and other ceramics materials.

3.
BMC Musculoskelet Disord ; 23(1): 907, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36217161

RESUMEN

BACKGROUND: Although treatment-resistant depression (TRD) is a major public health problem that increases mortality due to suicides, a considerable percentage of patients do not respond adequately to variable treatments. Patients with TRD sometimes have comorbid cervical stiffness. This observational study aims to examine the association of local modulation of cervical muscles with TRD and to learn the involvement of the parasympathetic nervous system in the underlying mechanism. METHODS: A total of 1103 hospitalized patients with TRD who were resistant to outpatient care were enrolled between May 2006 and October 2021. All patients underwent local modulation of the cervical muscles by physical therapy during hospitalization. The presence or absence of TRD and whole-body disorders, such as headache, dazzling, cervical stiffness, and cardiovascular and gastrointestinal disorders, was determined by the patient's subjectivity using the self-rated medical interview sheet at admission and discharge. Pupil light reflex parameters were also measured at admission and discharge using a binocular infrared pupilometer. RESULTS: The improvement rate of TRD during hospitalization was 72.1%, and did not differ significantly by sex, age, and hospitalization period. The improvement of TRD showed a strong association with those of cervical stiffness and dazzling, a pupil light reflex disorder (p < 0.001: odds ratios = 12.76 and 6.39, respectively), but not with those of headache or cardiovascular and gastrointestinal disorders (p > 0.05). In the TRD-improved patients, the pupil light reflex parameters representative of the parasympathetic nervous system function ameliorated: pupil diameter decreased, while constriction rate and velocity increased during hospitalization. In contrast, little amelioration of the parameters was seen in the TRD-unimproved patients. CONCLUSIONS: Cervical muscle stiffness may be associated with TRD, possibly through dysfunction of the parasympathetic nervous system. TRIAL REGISTRATION: ID: UMIN000040590. First registration date: 30/05/2020.


Asunto(s)
Depresión , Suicidio , Cefalea , Humanos , Músculos , Sistema Nervioso Parasimpático
4.
J Phys Chem B ; 126(31): 5793-5802, 2022 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-35913127

RESUMEN

We investigated d-amino acids as potential inhibitors targeting l-peptide toxins. Among the l- and d-amino acids tested, we found that d-tryptophan (d-Trp) acted as an inhibitor of melittin-induced hemolysis. We then evaluated various Trp derivatives and found that 5-chlorotryptamine (5CT) had the largest inhibitory effect on melittin. The indole ring, amino group, and steric hindrance of an inhibitor played important roles in the inhibition of melittin activity. Despite the small size and simple molecular structure of 5CT, its IC50 was approximately 13 µg/mL. Fluorescence quenching, circular dichroism measurements, and size-exclusion chromatography revealed that 5CT interacted with Trp19 in melittin and affected the formation of the melittin tetramer involved in hemolysis. Molecular dynamics simulation of melittin also indicated that the interaction of 5CT with Trp19 in melittin affected the formation of the tetramer.


Asunto(s)
Hemólisis , Meliteno , Dicroismo Circular , Humanos , Indoles , Meliteno/química , Meliteno/farmacología , Triptófano/química
5.
Gan To Kagaku Ryoho ; 49(13): 1553-1555, 2022 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-36733132

RESUMEN

This study aimed to investigate the short- and long-term outcomes in patients with sarcopenia who underwent surgery for advanced gastric cancer. We included 76 patients with pStage Ⅱ or Ⅲ gastric cancer who underwent gastrectomy between January 2017 and June 2021. Patients with pT3N0 cancer were excluded. Using the Asian Working Group for Sarcopenia( AWGS)2019 criteria, the patients were divided into the sarcopenia group(S group)and the non-sarcopenia group (NS group). The surgical outcomes, effects on postoperative adjuvant chemotherapy, and prognosis of the 2 groups were evaluated and compared. No significant differences were observed in the operative time, blood loss, postoperative hospital stays, or incidence of postoperative complications with a grade higher than Clavien-Dindo Grade Ⅱ. The number of patients who received postoperative adjuvant chemotherapy was 5(26.3%)in the S group and 38(66.7%)in the NS group which was significantly lower in the S group(p=0.003). The 3-year overall survival rate was 45.7% in the S group and 71.0% in the NS group(p=0.302). There was no significant difference but survival rate was lower in the S group. The results suggest that postoperative adjuvant chemotherapy is not always available for patients with advanced gastric cancer, and that may worsen the prognosis.


Asunto(s)
Sarcopenia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía , Factores de Riesgo , Pronóstico , Sarcopenia/complicaciones , Sarcopenia/epidemiología , Incidencia , Gastrectomía/efectos adversos , Gastrectomía/métodos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
6.
Gan To Kagaku Ryoho ; 49(13): 1631-1633, 2022 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-36733158

RESUMEN

A 35-year-old women with sigmoid cancer(pT4aN1aM0, pStage Ⅲb)underwent laparoscopic sigmoidectomy. She had 8 courses of CapeOX for adjuvant chemotherapy, but follow up CT scan 1 year after the operation detected intraabdominal nodules in anastomotic site and in left lower quadrant of abdomen. After 10 courses of IRIS plus bevacizumab, the both intraabdominal nodules decreased in size. Robot assisted laparoscopic lower anterior resection and laparoscopic disseminated nodule resection were performed. The patient had no postoperative complications and the postoperative course was good. She remains alive without recurrence at 6 months after the second operation.


Asunto(s)
Neoplasias Peritoneales , Procedimientos Quirúrgicos Robotizados , Neoplasias del Colon Sigmoide , Humanos , Femenino , Adulto , Neoplasias Peritoneales/tratamiento farmacológico , Neoplasias Peritoneales/cirugía , Peritoneo , Bevacizumab/uso terapéutico , Neoplasias del Colon Sigmoide/tratamiento farmacológico , Neoplasias del Colon Sigmoide/cirugía , Recurrencia Local de Neoplasia
7.
BMC Musculoskelet Disord ; 22(1): 419, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33952227

RESUMEN

BACKGROUND: Patients with myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) sometimes present with stiffness of the cervical muscles. To investigate the pathophysiology of ME/CFS, this observational study compared patients with versus without recovery from ME/CFS through local modulation of the cervical muscles. METHODS: Over a period of 11 years, a total of 1226 inpatients with ME/CFS who did not respond to outpatient care were enrolled in this study. All patients received daily cervical muscle physical therapy during hospitalization. Self-rated records documenting the presence or absence of ME/CFS, as well as the representative eight symptoms that frequently accompany it at admission and discharge, were compared. Pupil diameter was also measured to examine autonomic nervous system function involvement. RESULTS: The recovery rate of ME/CFS after local therapy was 55.5%, and did not differ significantly by sex, age strata, and hospitalization period. The recovery rates of the eight symptoms were variable (36.6-86.9%); however, those of ME/CFS in the symptom subpopulations were similar (52.3-55.8%). The recovery rates of all symptoms showed strong associations with that of ME/CFS (p < 0.001). The pupil diameter was more constricted in the ME/CFS-recovered patients than in the ME/CFS-unrecovered patients in the total population and the subpopulations stratified by sex, age, and hospitalization period. CONCLUSIONS: There was a strong association between the recovery of ME/CFS and other related whole-body symptoms. The recovery of ME/CFS may be partly linked to amelioration of the autonomic nervous system in the cervical muscles. TRIAL REGISTRATION: UMIN000036634 . Registered 1 May 2019 - Retrospectively registered.


Asunto(s)
Síndrome de Fatiga Crónica , Sistema Nervioso Autónomo , Síndrome de Fatiga Crónica/diagnóstico , Síndrome de Fatiga Crónica/epidemiología , Humanos , Músculos
8.
RSC Adv ; 11(38): 23409-23417, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35479813

RESUMEN

We propose a novel approach to stably immobilize gold nanoparticles (AuNPs) on a plastic substrate and demonstrate that the modified substrate is also capable of immobilizing biomolecules. To immobilize citrate-capped AuNPs, an acrylic substrate was simply dip-coated in a functional polymer solution to decorate the outermost surface with amino groups. Electrostatic interactions between AuNPs and the amino groups immobilized the AuNPs with a high density. The AuNP-modified acrylic substrate was transparent with a red tint. A heat treatment promoted the formation of amide bonds between carboxy groups on the AuNPs and amino groups on the substrate surface. These covalent bonds stabilized the immobilized AuNPs and the resulting substrate was resistant to washing with acid and thiol-containing solutions. The surface density of AuNPs was controlled by the surface density of amino groups on the substrate surface, which was in turn controlled by the dip-coating in the functional polymer solution. We attempted to immobilize functional biomolecules on the AuNPs-functionalized plastic surface by two different approaches. An enzyme (horseradish peroxidase) was successfully immobilized on the AuNPs through amide formation and 5'-thiolated DNA was also immobilized on the AuNPs through S-Au interactions. These chemistries allow for simultaneous immobilization of two different kinds of biomolecules on a plastic substrate without loss of their functional properties.

9.
Chem Commun (Camb) ; 56(58): 8107-8110, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32555815

RESUMEN

We experimentally and computationally investigated the Ca substitution effect on the electrochemical performance of P3-NaxCoO2. The cycle performance of Ca-substituted NaxCa0.04CoO2 was effectively improved due to its better crystallinity retention after charging. Our DFT calculations suggested that the presence of Ca2+ ions in Na sites kinetically mitigates phase transition.

10.
ACS Appl Mater Interfaces ; 12(23): 25775-25785, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32395982

RESUMEN

To clarify the origin of the polarization of magnesium deposition/dissolution reactions, we combined electrochemical measurement, operando soft X-ray absorption spectroscopy (operando SXAS), Raman, and density functional theory (DFT) techniques to three different electrolytes: magnesium bis(trifluoromethanesulfonyl)amide (Mg(TFSA)2)/triglyme, magnesium borohydride (Mg(BH4)2)/tetrahydrofuran (THF), and Mg(TFSA)2/2-methyltetrahydrofuran (2-MeTHF). Cyclic voltammetry revealed that magnesium deposition/dissolution reactions occur in Mg(TFSA)2/triglyme and Mg(BH4)2/THF, while the reactions do not occur in Mg(TFSA)2/2-MeTHF. Raman spectroscopy shows that the [TFSA]- in the Mg(TFSA)2/triglyme electrolyte largely does not coordinate to the magnesium ions, while all of the [TFSA]- in Mg(TFSA)2/2-MeTHF and [BH4]- in Mg(BH4)2/THF coordinate to the magnesium ions. In operando SXAS measurements, the intermediate, such as the Mg+ ion, was not observed at potentials above the magnesium deposition potential, and the local structure distortion around the magnesium ions increases in all of the electrolytes at the magnesium electrode|electrolyte interface during the cathodic polarization. Our DFT calculation and X-ray photoelectron spectroscopy results indicate that the [TFSA]-, strongly bound to the magnesium ion in the Mg(TFSA)2/2-MeTHF electrolyte, undergoes reduction decomposition easily, instead of deposition of magnesium metal, which makes the electrolyte inactive electrochemically. In the Mg(BH4)2/THF electrolyte, because the [BH4]- coordinated to the magnesium ions is stable even under the potential of the magnesium deposition, the magnesium deposition is not inhibited by the decomposition of [BH4]-. Conversely, because [TFSA]- is weakly bound to the magnesium ion in Mg(TFSA)2/triglyme, the reduction decomposition occurs relatively slowly, which allows the magnesium deposition in the electrolyte.

11.
Gan To Kagaku Ryoho ; 47(13): 2421-2423, 2020 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-33468981

RESUMEN

An 84-year-old man on hemodialysis was referred to our department for an advanced gastric cancer with pyloric stenosis. Pre-operative CT showed thickening of the stomach wall at the primary lesion and regional lymph node metastasis, while no clear peritoneal metastasis was found. However, we found peritoneal disseminations during the operation, so gastrojejunal bypass was performed. After the operation, he hoped chemotherapy despite risk factors such as renal failure and old age. We introduced a reduced dose of weekly nab-paclitaxel to him. After 3 courses, CT showed the primary lesion had decreased in size, and after 6 courses, serum CA19-9 level decreased to 61.8 U/mL from 2,343 U/mL at the before treatment. No serious adverse events were observed during the chemotherapy. However, after 8 courses, the tumor markers was gradually re-increased, and CT showed the primary tumor re-increased after 9 courses. Therefore, he received irinotecan alone as the second-line. He is still alive 1 year and 8 months after diagnosis of gastric cancer. It is generally said that the risk of cancer chemotherapy for dialysis patients and the elderly is high. However, we suggest that it could be safely performed by examining the appropriate drug and dose. Weekly nab-paclitaxel regimen could be one of the promising options for these patients.


Asunto(s)
Neoplasias Gástricas , Anciano , Anciano de 80 o más Años , Albúminas , Protocolos de Quimioterapia Combinada Antineoplásica , Humanos , Masculino , Paclitaxel/uso terapéutico , Diálisis Renal , Neoplasias Gástricas/tratamiento farmacológico
12.
Front Chem ; 7: 7, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30729105

RESUMEN

Passivation of magnesium metal anode is one of the critical challenges for the development of magnesium batteries. Here we investigated the passivation process of an intermetallic anode: Mg3Bi2 synthesized by solid-state and thin film process. The Mg3Bi2 composite electrode shows excellent reversibility in magnesium bis(trifluoromethansulfonylamide) dissolved in acetonitrile, while Mg3Sb2, which has same crystal structure and similar chemical properties, is electrochemically inactive. We also fabricated the Mg3Bi2 thin film electrodes, which show reversibility with low overpotential not only in the acetonitrile solution but also glyme-based solutions. Surface layer corresponding to the decomposed TFSA anion is slightly suppressed in the case of the Mg3Bi2 thin film electrode, compared with Mg metal. Comparative study of hydrolysis process of the Mg3Bi2 and the Mg3Sb2 suggests that the both intermetallic anodes are not completely passivated. The bond valence sum mapping of the Mg3Bi2 indicates that the fast Mg2+ diffusion pathway between 2d tetrahedral sites is formed. The electrochemical properties of the Mg3Bi2 anode is mainly due to the less passivation surface with the fast Mg2+ diffusion pathways.

13.
J Org Chem ; 83(8): 4389-4401, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29578346

RESUMEN

NIR absorbing squaraine dyes SQ1-SQ7 having 1 H-benzo[ c, d]indol-2-ylidene as a donor moiety were designed for application in DSSCs. Annulation of the benzene ring to an 3 H-indolium-based anchor moiety led to a red-shifted and broadened absorption band on TiO2 film, which were reflected in the improved short-circuit current density of SQ2 (6.22 mA cm-2) compared to the nonbenzene fused derivative SQ1 (4.39 mA cm-2). Although the introduction of a butoxy (SQ4: 806 nm) or dialkylamino group (SQ5-SQ7: 815-820 nm) to the 1 H-benzo[ c, d]indol-2-ylidene-based donor moiety resulted in red-shifted absorption maxima in ethanol compared to the nonsubstituted derivative SQ2 (784 nm), the HOMO energy level of SQ4-SQ7 gave rise to an undesirable approximation to the redox potential of I-/I3-. Thus, the butoxy (SQ4: 0.56) and dialkylamino (SQ5-SQ7: 0.25-0.30) derivatives had relatively lower conversion efficiencies. Since the 2-ethylhexyl derivative SQ3 exhibited red-shifted absorption (λmax: 796 nm), suitable HOMO and LUMO energy levels, and relatively efficient restriction of charge recombination, this dye achieved the highest conversion efficiency (1.31%), along with a high IPCE response of over 20% over a wide range from 640 to 860 nm and an onset of IPCE at 1000 nm.

14.
Nat Commun ; 8: 15106, 2017 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-28440299

RESUMEN

Reversible dendrite-free low-areal-capacity lithium metal electrodes have recently been revived, because of their pivotal role in developing beyond lithium ion batteries. However, there have been no reports of reversible dendrite-free high-areal-capacity lithium metal electrodes. Here we report on a strategy to realize unprecedented stable cycling of lithium electrodeposition/stripping with a highly desirable areal-capacity (12 mAh cm-2) and exceptional Coulombic efficiency (>99.98%) at high current densities (>5 mA cm-2) and ambient temperature using a diluted solvate ionic liquid. The essence of this strategy, that can drastically improve lithium electrodeposition kinetics by cyclic voltammetry premodulation, lies in the tailoring of the top solid-electrolyte interphase layer in a diluted solvate ionic liquid to facilitate a two-dimensional growth mode. We anticipate that this discovery could pave the way for developing reversible dendrite-free metal anodes for sustainable battery chemistries.

15.
Chemistry ; 22(5): 1816-24, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26670268

RESUMEN

Pyrimidine-based diboron complexes bearing ß-iminoenolate ligands and phenyl groups as bulky substituents on the boron atoms were synthesized as novel fluorescent dyes, and their fluorescence properties were investigated in solution and in the solid state. The diboron complexes with donor-π-acceptor structures showed positive solvatochromism in the fluorescence spectra. The cyano derivative exhibited the most dramatic redshift of the fluorescence maximum Fmax with increasing solvent polarity (from 551 nm in n-hexane to 710 nm in acetonitrile). The diboron complexes showed solid-state fluorescence in the range of 578-706 nm with fluorescence quantum yields of 0.06-0.28. Additionally, the trifluoromethyl derivative exhibited solvent-inclusion solid-state fluorescence. The trifluoromethyl derivative formed toluene-inclusion and ethyl acetate-inclusion crystals. The toluene-inclusion crystal (Fmax = 668 nm, Φf = 0.16) showed a blueshifted Fmax and higher Φf value compared to the original trifluoromethyl derivative (Fmax = 694 nm, Φf = 0.08) in the solid state. On the other hand, the Fmax (709 nm) and Φf (0.04) values of the ethyl acetate-inclusion crystal were redshifted and lower, respectively.

16.
Chem Asian J ; 10(12): 2701-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26206587

RESUMEN

A direct, concise, and enantioselective synthesis of 2-substituted 4,4,4-trifluorobutane-1,3-diols based on the organocatalytic asymmetric direct aldol reaction of an ethyl hemiacetal of trifluoroacetaldehyde with various aldehydes was examined. A catalytic amount (30 mol %) of commercially available and inexpensive l-prolinamide is quite effective as an organocatalyst for the catalytic in situ generation of gaseous and unstable trifluoroacetaldehyde from its hemiacetal, and a successive asymmetric direct aldol reaction with various aldehydes in dichloromethane at 0 °C, followed by reduction with sodium borohydride, gives 2-substituted 4,4,4-trifluorobutane-1,3-diols in moderate to good yields (31-84%) with low diastereoselectivities and good to excellent enantioselectivities (64-97% ee).


Asunto(s)
Acetaldehído/análogos & derivados , Butileno Glicoles/química , Acetaldehído/química , Aldehídos/química , Borohidruros/química , Butileno Glicoles/síntesis química , Catálisis , Cetonas/química , Cloruro de Metileno/química , Oxidación-Reducción , Prolina/análogos & derivados , Prolina/química , Estereoisomerismo
17.
Org Lett ; 17(12): 3174-7, 2015 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-26067338

RESUMEN

Novel bisboron complexes of bidentate ligands consisting of 1,4-benzoquinone and two pyrrole rings were synthesized by using a simple two-step reaction. In solution, the bisboron complexes showed absorption maxima at ∼620 and 800 nm, which were attributed to the allowed S0 → S2 and forbidden S0 → S1 transitions, respectively. The bisboron complexes did not show any fluorescence, probably because of their highly symmetrical structure which forbids the S0 → S1 transition. Bisboron complexes underwent a two-electron reduction to yield the corresponding aromatic dianion, which showed absorption maxima at ∼410 nm.


Asunto(s)
Aniones/química , Benzoquinonas/síntesis química , Benzoquinonas/química , Compuestos de Boro/química , Electroquímica , Electrones , Ligandos , Estructura Molecular
18.
Solid State Nucl Magn Reson ; 70: 21-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26051010

RESUMEN

The garnet-type solid conductor Li7-xLa3Zr2-xTaxO12 is known to have high ionic conductivity. We synthesized a series of compositions of this conductor and found that cubic Li6.6La3Zr1.6Ta0.4O12 (LLZO-Ta) has a high ionic conductivity of 3.7×10(-4)Scm(-1) at room temperature. The (7)Li NMR spectrum of LLZO-Ta was composed of narrow and broad components, and the linewidth of the narrow component varied from 0.69kHz (300K) to 0.32kHz (400K). We carried out lithium ion diffusion measurements using pulsed-field spin-echo (PGSE) NMR spectroscopy and found that echo signals were observed at T≥313K with reasonable sensitivity. The lithium diffusion behavior was measured by varying the observation time and pulsed-field gradient (PFG) strength between 313 and 384K. We found that lithium diffusion depended significantly on the observation time and strength of the PFG, which is quite different from lithium ion diffusion in liquids. It was shown that lithium ion migration in the solid conductor was distributed widely in both time and space.

19.
J Org Chem ; 80(14): 7317-20, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26086525

RESUMEN

A Pd-catalyzed oxidative silylation of simple olefins with hexamethyldisilane to give allylsilanes has been achieved using molecular oxygen as the sole oxidant. The reaction provides a useful protocol to access synthetically useful allylsilanes from easily accessible simple olefins and hexamethyldisilane without using any oxidants other than O2.

20.
Chem Commun (Camb) ; 51(15): 3189-92, 2015 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-25603771

RESUMEN

The electrochemical process of an aqueous Li-O2 cell is investigated. Li2O2 is detected as a discharge product of an aqueous Li-O2 cell using a catalyst-free carbon-based electrode. The electrolyte solution saturated with lithium hydroxide prevents hydrolysis of the Li2O2. Since the electron transfer process is based on the oxygen-peroxide redox couple, the galvanostatic charging-discharging profile shows stable cycling with an extremely low charging overpotential of <0.1 V at 1.0 mA cm(-2).

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